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Sample records for intravaginal electronic brachytherapy

  1. Determination of Prognostic Factors for Vaginal Mucosal Toxicity Associated With Intravaginal High-Dose Rate Brachytherapy in Patients With Endometrial Cancer

    International Nuclear Information System (INIS)

    Bahng, Agnes Y.; Dagan, Avner; Bruner, Deborah W.; Lin, Lilie L.

    2012-01-01

    Purpose: The objective of this study was to determine the patient- and treatment-related prognostic factors associated with vaginal toxicity in patients who received intravaginal high dose rate (HDR) brachytherapy alone as adjuvant treatment for endometrial cancer. Secondary goals of this study included a quantitative assessment of optimal dilator use frequency and a crude assessment of clinical predictors for compliant dilator use. Methods and Materials: We retrospectively reviewed the charts of 100 patients with histologically confirmed endometrial cancer who underwent total hysterectomy and bilateral salpingo-oophorectomy with or without lymph node dissection and adjuvant intravaginal brachytherapy between 1995 and 2009 at the Hospital of University of Pennsylvania. The most common treatment regimen used was 21 Gy in three fractions (71 patients). Symptoms of vaginal mucosal toxicity were taken from the history and physical exams noted in the patients’ charts and were graded according to the Common Toxicity Criteria for Adverse Events v. 4.02. Results: The incidence of Grade 1 or asymptomatic vaginal toxicity was 33% and Grade 2–3 or symptomatic vaginal toxicity was 14%. Multivariate analysis of age, active length, and dilator use two to three times a week revealed odds ratios of 0.93 (p = 0.013), 3.96 (p = 0.008), and 0.17 (p = 0.032) respectively. Conclusion: Increasing age, vaginal dilator use of at least two to three times a week, and shorter active length were found to be significantly associated with a decreased risk of vaginal stenosis. Future prospective studies are necessary to validate our findings.

  2. Determination of Prognostic Factors for Vaginal Mucosal Toxicity Associated With Intravaginal High-Dose Rate Brachytherapy in Patients With Endometrial Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bahng, Agnes Y.; Dagan, Avner [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Bruner, Deborah W. [University of Pennsylvania School of Nursing, Philadelphia, PA (United States); Lin, Lilie L., E-mail: lin@xrt.upenn.edu [Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    2012-02-01

    Purpose: The objective of this study was to determine the patient- and treatment-related prognostic factors associated with vaginal toxicity in patients who received intravaginal high dose rate (HDR) brachytherapy alone as adjuvant treatment for endometrial cancer. Secondary goals of this study included a quantitative assessment of optimal dilator use frequency and a crude assessment of clinical predictors for compliant dilator use. Methods and Materials: We retrospectively reviewed the charts of 100 patients with histologically confirmed endometrial cancer who underwent total hysterectomy and bilateral salpingo-oophorectomy with or without lymph node dissection and adjuvant intravaginal brachytherapy between 1995 and 2009 at the Hospital of University of Pennsylvania. The most common treatment regimen used was 21 Gy in three fractions (71 patients). Symptoms of vaginal mucosal toxicity were taken from the history and physical exams noted in the patients' charts and were graded according to the Common Toxicity Criteria for Adverse Events v. 4.02. Results: The incidence of Grade 1 or asymptomatic vaginal toxicity was 33% and Grade 2-3 or symptomatic vaginal toxicity was 14%. Multivariate analysis of age, active length, and dilator use two to three times a week revealed odds ratios of 0.93 (p = 0.013), 3.96 (p = 0.008), and 0.17 (p = 0.032) respectively. Conclusion: Increasing age, vaginal dilator use of at least two to three times a week, and shorter active length were found to be significantly associated with a decreased risk of vaginal stenosis. Future prospective studies are necessary to validate our findings.

  3. Auger Electron Therapy And Brachytherapy Tumor Treatment

    International Nuclear Information System (INIS)

    Laster, B.H.; Shani, G.

    2002-01-01

    Auger Electron Therapy (AET) is a binary approach for improving cancer radiotherapy. It involves the selective targeting of an atom to tumor cells using physiological pathway. The atom is then irradiated by a specific radiation that produces secondary radiation called Auger electrons. One of the problems associated with the clinical application of AET, is that the energy of the photons required for stimulating photoelectric absorption in most of the available high Z target atoms, is too low to achieve penetration through normal surrounding tissues to the depth of the tumor, when an external source is used. The solution is therefore the use of a brachytherapy technique. There are two other problems associated with the use of radiation as a cancer treatment. The first is the limitation on radiation dose to the normal tissue within the treatment volume. The second problem is the limitation imposed by the miniscule size of the critical target of the cell, namely the DNA (0.25% of the cell mass). The solution to the first problem can be achieved by using the brachytherapy technique. The second problem can be resolved by placing the radiation source in close position to the DNA. AET, as we apply it, provides the two solutions to the two problems. When a photon is absorbed by an electron in the K or L shell of an high Z atom, the electron is ejected from the atom, creating a vacancy in the shell. This vacancy is immediately filled with an electron from an upper shell. The energy difference between the two shells is sometimes emitted as an x-ray, however, frequently the energy is transferred to an outer shell electron that is emitted as an Auger electron. These electrons are emitted at energies of up to ∼30 keV and therefore have a very short range in the cell. They will deposit all their energy within 20-30 nm from the point of emission. i.e. all the energy is deposited in the DNA. In our work indium is used as the high Z atom

  4. Electronic brachytherapy management of atypical fibroxanthoma: report of 8 lesions

    Directory of Open Access Journals (Sweden)

    Stephen Doggett

    2017-01-01

    Full Text Available Purpose : To evaluate the suitability of treating atypical fibroxanthoma (AFX, an uncommon skin malignancy, with electronic brachytherapy. Material and methods : From Feb 2013 to Sep 2014, we were referred a total of 8 cases of AFX in 7 patients, all involving the scalp. All of them were treated with electronic brachytherapy 50 Kev radiations (Xoft Axxent®, Fremont, California. All lesions received 40 Gy in two fractions per week with 5mm margins. Results : At a median follow-up of 23.7 months, the local recurrence rate is 12.5%. The single lesion that failed was not debulked surgically prior to electronic brachytherapy. Conclusions : To our knowledge, this is the first report in the literature on the use of radiation therapy as curative primary treatment for AFX. No contraindication to the use of radiations is found in the literature, with surgery being the sole treatment for AFX noted. Our recurrence rate is 0% for debulked lesions. Risk of recurrence is mitigated with surgical debulking prior to brachytherapy. Electronic brachytherapy appears to be a safe and effective treatment for debulked AFX. Multiple excisions, skin grafting, and wound care can be avoided in elderly patients by the use of electronic brachytherapy.

  5. Brachytherapy

    Science.gov (United States)

    ... the use of a type of energy, called ionizing radiation, to kill cancer cells and shrink tumors. External ... In all cases of brachytherapy, the source of radiation is encapsulated ... non-radioactive metallic capsule. This prevents the radioactive materials ...

  6. Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent X-Ray Source: an electronic brachytherapy source.

    Science.gov (United States)

    Rivard, Mark J; Davis, Stephen D; DeWerd, Larry A; Rusch, Thomas W; Axelrod, Steve

    2006-11-01

    A new x-ray source, the model S700 Axxent X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, S700 Source exhibited depth dose behavior similar to low-energy photon-emitting low dose rate sources 125I and l03Pd, yet with capability for variable and much higher dose rates and subsequently adjustable penetration capabilities. This paper presents the calculated and measured in-water brachytherapy dosimetry parameters for the model S700 Source at the aforementioned three operating voltages.

  7. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy

    Directory of Open Access Journals (Sweden)

    Kasper ME

    2015-11-01

    Full Text Available Michael E Kasper,1,2 Ahmed A Chaudhary3 1Department of Radiation Oncology, Lynn Cancer Institute at Boca Raton Regional Hospital, Boca Raton, 2Charles E. Schmidt College of Medicine, Florida Atlantic University, FL, 3North Main Radiation Oncology, Warren Alpert School of Medicine, Brown University, RI, USA Abstract: Nonmelanoma skin cancer (NMSC is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and 226Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy. Keywords: electronic brachytherapy, superficial radiotherapy, skin surface brachytherapy, electron beam therapy, nonmelanoma skin cancer, basal cell carcinoma, squamous cell carcinoma

  8. Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent X-Ray Source: An electronic brachytherapy source

    International Nuclear Information System (INIS)

    Rivard, Mark J.; Davis, Stephen D.; DeWerd, Larry A.; Rusch, Thomas W.; Axelrod, Steve

    2006-01-01

    A new x-ray source, the model S700 Axxent trade mark sign X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, P (5) were 0.20, 0.24, and 0.29 for the 40, 45, and 50 kV voltage settings, respectively. For 1 125 I and 103 Pd, yet with capability for variable and much higher dose rates and subsequently adjustable penetration capabilities. This paper presents the calculated and measured in-water brachytherapy dosimetry parameters for the model S700 Source at the aforementioned three operating voltages

  9. Evaluation of high-energy brachytherapy source electronic disequilibrium and dose from emitted electrons.

    Science.gov (United States)

    Ballester, Facundo; Granero, Domingo; Pérez-Calatayud, José; Melhus, Christopher S; Rivard, Mark J

    2009-09-01

    The region of electronic disequilibrium near photon-emitting brachytherapy sources of high-energy radionuclides (60Co, 137CS, 192Ir, and 169Yb) and contributions to total dose from emitted electrons were studied using the GEANT4 and PENELOPE Monte Carlo codes. Hypothetical sources with active and capsule materials mimicking those of actual sources but with spherical shape were examined. Dose contributions due to source photons, x rays, and bremsstrahlung; source beta-, Auger electrons, and internal conversion electrons; and water collisional kerma were scored. To determine if conclusions obtained for electronic equilibrium conditions and electron dose contribution to total dose for the representative spherical sources could be applied to actual sources, the 192Ir mHDR-v2 source model (Nucletron B.V., Veenendaal, The Netherlands) was simulated for comparison to spherical source results and to published data. Electronic equilibrium within 1% is reached for 60Co, 137CS, 192Ir, and 169Yb at distances greater than 7, 3.5, 2, and 1 mm from the source center, respectively, in agreement with other published studies. At 1 mm from the source center, the electron contributions to total dose are 1.9% and 9.4% for 60Co and 192Ir, respectively. Electron emissions become important (i.e., > 0.5%) within 3.3 mm of 60Co and 1.7 mm of 192Ir sources, yet are negligible over all distances for 137Cs and 169Yb. Electronic equilibrium conditions along the transversal source axis for the mHDR-v2 source are comparable to those of the spherical sources while electron dose to total dose contribution are quite different. Electronic equilibrium conditions obtained for spherical sources could be generalized to actual sources while electron contribution to total dose depends strongly on source dimensions, material composition, and electron spectra.

  10. MO-D-BRD-01: Clinical Implementation of An Electronic Brachytherapy Program for the Skin

    International Nuclear Information System (INIS)

    Ouhib, Z.

    2015-01-01

    Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air-kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir-192 sources. Consequently, tissue-specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations. Learning Objectives: To understand the basic principles of electronic

  11. MO-D-BRD-03: Radiobiology and Commissioning of Electronic Brachytherapy for IORT

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J. [Oregon Health & Science Univ (United States)

    2015-06-15

    Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air-kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir-192 sources. Consequently, tissue-specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations. Learning Objectives: To understand the basic principles of electronic

  12. MO-A-BRB-02: Considerations and Issues in Electronic Charting for Brachytherapy

    International Nuclear Information System (INIS)

    Richardson, S.

    2015-01-01

    The process of converting to an electronic chart for radiation therapy can be daunting. It requires a dedicated committee to first research and choose appropriate software, to review the entire documentation policy and flow of the clinic, to convert this system to electronic form or if necessary, redesign the system to more easily conform to the electronic process. Those making the conversion and those who already use electronic charting would benefit from the shared experience of those who have been through the process in the past. Therefore TG262 was convened to provide guidance on electronic charting for external beam radiation therapy and brachytherapy. This course will present the results of an internal survey of task group members on EMR practices in External Beam Radiation Therapy as well as discuss important issues in EMR development and structure for both EBRT and brachytherapy. Learning Objectives: Be familiarized with common practices and pitfalls in development and maintenance of an electronic chart in Radiation Oncology Be familiarized with important issues related to electronic charting in External Beam Radiation Therapy Be familiarized with important issues related to electronic charting in Brachytherapy

  13. MO-A-BRB-00: Electronic Charting in EBRT and Brachytherapy

    International Nuclear Information System (INIS)

    2015-01-01

    The process of converting to an electronic chart for radiation therapy can be daunting. It requires a dedicated committee to first research and choose appropriate software, to review the entire documentation policy and flow of the clinic, to convert this system to electronic form or if necessary, redesign the system to more easily conform to the electronic process. Those making the conversion and those who already use electronic charting would benefit from the shared experience of those who have been through the process in the past. Therefore TG262 was convened to provide guidance on electronic charting for external beam radiation therapy and brachytherapy. This course will present the results of an internal survey of task group members on EMR practices in External Beam Radiation Therapy as well as discuss important issues in EMR development and structure for both EBRT and brachytherapy. Learning Objectives: Be familiarized with common practices and pitfalls in development and maintenance of an electronic chart in Radiation Oncology Be familiarized with important issues related to electronic charting in External Beam Radiation Therapy Be familiarized with important issues related to electronic charting in Brachytherapy

  14. American Society for Therapeutic Radiology and Oncology (ASTRO) Emerging Technology Committee report on electronic brachytherapy.

    Science.gov (United States)

    Park, Catherine C; Yom, Sue S; Podgorsak, Matthew B; Harris, Eleanor; Price, Robert A; Bevan, Alison; Pouliot, Jean; Konski, Andre A; Wallner, Paul E

    2010-03-15

    The development of novel technologies for the safe and effective delivery of radiation is critical to advancing the field of radiation oncology. The Emerging Technology Committee of the American Society for Therapeutic Radiology and Oncology appointed a Task Group within its Evaluation Subcommittee to evaluate new electronic brachytherapy methods that are being developed for, or are already in, clinical use. The Task Group evaluated two devices, the Axxent Electronic Brachytherapy System by Xoft, Inc. (Fremont, CA), and the Intrabeam Photon Radiosurgery Device by Carl Zeiss Surgical (Oberkochen, Germany). These devices are designed to deliver electronically generated radiation, and because of their relatively low energy output, they do not fall under existing regulatory scrutiny of radioactive sources that are used for conventional radioisotope brachytherapy. This report provides a descriptive overview of the technologies, current and future projected applications, comparison of competing technologies, potential impact, and potential safety issues. The full Emerging Technology Committee report is available on the American Society for Therapeutic Radiology and Oncology Web site. Copyright 2010. Published by Elsevier Inc.

  15. American Society for Therapeutic Radiology and Oncology (ASTRO) Emerging Technology Committee Report on Electronic Brachytherapy

    International Nuclear Information System (INIS)

    Park, Catherine C.; Yom, Sue S.; Podgorsak, Matthew B.; Harris, Eleanor; Price, Robert A.; Bevan, Alison; Pouliot, Jean; Konski, Andre A.; Wallner, Paul E.

    2010-01-01

    The development of novel technologies for the safe and effective delivery of radiation is critical to advancing the field of radiation oncology. The Emerging Technology Committee of the American Society for Therapeutic Radiology and Oncology appointed a Task Group within its Evaluation Subcommittee to evaluate new electronic brachytherapy methods that are being developed for, or are already in, clinical use. The Task Group evaluated two devices, the Axxent Electronic Brachytherapy System by Xoft, Inc. (Fremont, CA), and the Intrabeam Photon Radiosurgery Device by Carl Zeiss Surgical (Oberkochen, Germany). These devices are designed to deliver electronically generated radiation, and because of their relatively low energy output, they do not fall under existing regulatory scrutiny of radioactive sources that are used for conventional radioisotope brachytherapy. This report provides a descriptive overview of the technologies, current and future projected applications, comparison of competing technologies, potential impact, and potential safety issues. The full Emerging Technology Committee report is available on the American Society for Therapeutic Radiology and Oncology Web site.

  16. SU-E-T-447: Electronic Brachytherapy (EBT) Treatment of Cervical Cancer - First Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D; Johnson, M; Thompson, J; Ahmad, S [University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Chan, L; Hausen, H [Xoft Inc., San Jose, CA (United States)

    2014-06-01

    Purpose: To study the first trial patient in which an electronic brachytherapy (EBT) x-ray source is utilized for treatment of cervical cancer. Methods: During patient treatment, a miniaturized x-ray source was used in combination with a customized titanium tandem and ovoid applicator set. The semi-specialized source was modeled with formalisms outlined by AAMP Task Group 43. Multiple models were used to compensate for variable attenuation conditions as a function of source positions. Varian Brachyvision treatment planning software was utilized on CT data sets for dose calculations prior to treatment delivery. The dose was prescribed to “point A” as defined by American Brachytherapy society. Additional treatments plans were created from those clinically utilized in patient care and were recalculated for an existing Ir-192 source model. Dose volume histograms (DVH) and point dose calculations were compared between the modalities for the clinical condition present in patients treated with EBT. Results: Clinical treatment times, though longer than those typically experienced by Ir-192 users, were manageable. Instantaneous dose rates at personal positions within the treatment vault were lower than those measured during intra operative radiation therapy and breast EBT treatments. Due to lower average photon energy in EBT, dose gradients within the treatment plans were as expected steeper than those observed in Ir-192 based brachytherapy. DVH comparisons between Ir-192 and EBT treatments showed an expected decrease in the integral dose to normal tissues of interest for EBT. In comparing plans created for EBT delivery with those calculated for Ir-192, average dose values for EBT were more than 4%, 11%, and 9% lower at predefined bladder, rectum and “point B” positions, respectively. Conclusion: For the first time, we have demonstrated that the utilizing electronic brachytherapy system for tandem and ovoid based treatment of cancer of the cervix is feasible, and

  17. SU-E-P-05: Electronic Brachytherapy: A Physics Perspective On Field Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Pai, S; Ayyalasomayajula, S; Lee, S [iCAD Inc., Los Gatos, CA (United States)

    2015-06-15

    Purpose: We want to summarize our experience implementing a successful program of electronic brachytherapy at several dermatology clinics with the help of a cloud based software to help us define the key program parameters and capture physics QA aspects. Optimally developed software helps the physicist in peer review and qualify the physical parameters. Methods: Using the XOFT™ Axxent™ electronic brachytherapy system in conjunction with a cloud-based software, a process was setup to capture and record treatments. It was implemented initially at about 10 sites in California. For dosimetric purposes, the software facilitated storage of the physics parameters of surface applicators used in treatment and other source calibration parameters. In addition, the patient prescription, pathology and other setup considerations were input by radiation oncologist and the therapist. This facilitated physics planning of the treatment parameters and also independent check of the dwell time. From 2013–2014, nearly1500 such calculation were completed by a group of physicists. A total of 800 patients with multiple lesions have been treated successfully during this period. The treatment log files have been uploaded and documented in the software which facilitated physics peer review of treatments per the standards in place by AAPM and ACR. Results: The program model was implemented successfully at multiple sites. The cloud based software allowed for proper peer review and compliance of the program at 10 clinical sites. Dosimtery was done on 800 patients and executed in a timely fashion to suit the clinical needs. Accumulated physics data in the software from the clinics allows for robust analysis and future development. Conclusion: Electronic brachytherapy implementation experience from a quality assurance perspective was greatly enhanced by using a cloud based software. The comprehensive database will pave the way for future developments to yield superior physics outcomes.

  18. Design and dosimetric characteristics of a new endocavitary contact radiotherapy system using an electronic brachytherapy source.

    Science.gov (United States)

    Richardson, Susan; Garcia-Ramirez, Jose; Lu, Wei; Myerson, Robert J; Parikh, Parag

    2012-11-01

    To present design aspects and acceptance tests performed for clinical implementation of electronic brachytherapy treatment of early stage rectal adenocarcinoma. A dosimetric comparison is made between the historically used Philips RT-50 unit and the newly developed Axxent(®) Model S700 electronic brachytherapy source manufactured by Xoft (iCad, Inc.). Two proctoscope cones were manufactured by ElectroSurgical Instruments (ESI). Two custom surface applicators were manufactured by Xoft and were designed to fit and interlock with the proctoscope cones from ESI. Dose rates, half value layers (HVL), and percentage depth dose (PDD) measurements were made with the Xoft system and compared to historical RT-50 data. A description of the patient treatment approach and exposure rates during the procedure is also provided. The electronic brachytherapy system has a lower surface dose rate than the RT-50. The dose rate to water on the surface from the Xoft system is approximately 2.1 Gy∕min while the RT-50 is 10-12 Gy∕min. However, treatment times with Xoft are still reasonable. The HVLs and PDDs between the two systems were comparable resulting in similar doses to the target and to regions beyond the target. The exposure rate levels around a patient treatment were acceptable. The standard uncertainty in the dose rate to water on the surface is approximately ±5.2%. The Philips RT-50 unit is an out-of-date radiotherapy machine that is no longer manufactured with limited replacement parts. The use of a custom-designed proctoscope and Xoft surface applicators allows delivery of a well-established treatment with the ease of a modern radiotherapy device. While the dose rate is lower with the use of Xoft, the treatment times are still reasonable. Additionally, personnel may stand farther away from the Xoft radiation source, thus potentially reducing radiation exposure to the operator and other personnel.

  19. Design and dosimetric characteristics of a new endocavitary contact radiotherapy system using an electronic brachytherapy source

    International Nuclear Information System (INIS)

    Richardson, Susan; Garcia-Ramirez, Jose; Lu Wei; Myerson, Robert J.; Parikh, Parag

    2012-01-01

    Purpose: To present design aspects and acceptance tests performed for clinical implementation of electronic brachytherapy treatment of early stage rectal adenocarcinoma. A dosimetric comparison is made between the historically used Philips RT-50 unit and the newly developed Axxent ® Model S700 electronic brachytherapy source manufactured by Xoft (iCad, Inc.). Methods: Two proctoscope cones were manufactured by ElectroSurgical Instruments (ESI). Two custom surface applicators were manufactured by Xoft and were designed to fit and interlock with the proctoscope cones from ESI. Dose rates, half value layers (HVL), and percentage depth dose (PDD) measurements were made with the Xoft system and compared to historical RT-50 data. A description of the patient treatment approach and exposure rates during the procedure is also provided. Results: The electronic brachytherapy system has a lower surface dose rate than the RT-50. The dose rate to water on the surface from the Xoft system is approximately 2.1 Gy/min while the RT-50 is 10–12 Gy/min. However, treatment times with Xoft are still reasonable. The HVLs and PDDs between the two systems were comparable resulting in similar doses to the target and to regions beyond the target. The exposure rate levels around a patient treatment were acceptable. The standard uncertainty in the dose rate to water on the surface is approximately ±5.2%. Conclusions: The Philips RT-50 unit is an out-of-date radiotherapy machine that is no longer manufactured with limited replacement parts. The use of a custom-designed proctoscope and Xoft surface applicators allows delivery of a well-established treatment with the ease of a modern radiotherapy device. While the dose rate is lower with the use of Xoft, the treatment times are still reasonable. Additionally, personnel may stand farther away from the Xoft radiation source, thus potentially reducing radiation exposure to the operator and other personnel.

  20. Design and dosimetric characteristics of a new endocavitary contact radiotherapy system using an electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Susan; Garcia-Ramirez, Jose; Lu Wei; Myerson, Robert J.; Parikh, Parag [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States); Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States)

    2012-11-15

    Purpose: To present design aspects and acceptance tests performed for clinical implementation of electronic brachytherapy treatment of early stage rectal adenocarcinoma. A dosimetric comparison is made between the historically used Philips RT-50 unit and the newly developed Axxent{sup Registered-Sign} Model S700 electronic brachytherapy source manufactured by Xoft (iCad, Inc.). Methods: Two proctoscope cones were manufactured by ElectroSurgical Instruments (ESI). Two custom surface applicators were manufactured by Xoft and were designed to fit and interlock with the proctoscope cones from ESI. Dose rates, half value layers (HVL), and percentage depth dose (PDD) measurements were made with the Xoft system and compared to historical RT-50 data. A description of the patient treatment approach and exposure rates during the procedure is also provided. Results: The electronic brachytherapy system has a lower surface dose rate than the RT-50. The dose rate to water on the surface from the Xoft system is approximately 2.1 Gy/min while the RT-50 is 10-12 Gy/min. However, treatment times with Xoft are still reasonable. The HVLs and PDDs between the two systems were comparable resulting in similar doses to the target and to regions beyond the target. The exposure rate levels around a patient treatment were acceptable. The standard uncertainty in the dose rate to water on the surface is approximately {+-}5.2%. Conclusions: The Philips RT-50 unit is an out-of-date radiotherapy machine that is no longer manufactured with limited replacement parts. The use of a custom-designed proctoscope and Xoft surface applicators allows delivery of a well-established treatment with the ease of a modern radiotherapy device. While the dose rate is lower with the use of Xoft, the treatment times are still reasonable. Additionally, personnel may stand farther away from the Xoft radiation source, thus potentially reducing radiation exposure to the operator and other personnel.

  1. Simulation evaluation of NIST air-kerma rate calibration standard for electronic brachytherapy.

    Science.gov (United States)

    Hiatt, Jessica R; Rivard, Mark J; Hughes, H Grady

    2016-03-01

    Dosimetry for the model S700 50 kV electronic brachytherapy (eBT) source (Xoft, Inc., a subsidiary of iCAD, San Jose, CA) was simulated using Monte Carlo (MC) methods by Rivard et al. ["Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent x-ray source: An electronic brachytherapy source," Med. Phys. 33, 4020-4032 (2006)] and recently by Hiatt et al. ["A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model," Med. Phys. 42, 2764-2776 (2015)] with improved geometric characterization. While these studies examined the dose distribution in water, there have not previously been reports of the eBT source calibration methods beyond that recently reported by Seltzer et al. ["New national air-kerma standard for low-energy electronic brachytherapy sources," J. Res. Natl. Inst. Stand. Technol. 119, 554-574 (2014)]. Therefore, the motivation for the current study was to provide an independent determination of air-kerma rate at 50 cm in air K̇air(d=50 cm) using MC methods for the model S700 eBT source. Using CAD information provided by the vendor and disassembled sources, an MC model was created for the S700 eBT source. Simulations were run using the mcnp6 radiation transport code for the NIST Lamperti air ionization chamber according to specifications by Boutillon et al. ["Comparison of exposure standards in the 10-50 kV x-ray region," Metrologia 5, 1-11 (1969)], in air without the Lamperti chamber, and in vacuum without the Lamperti chamber. K̇air(d=50 cm) was determined using the *F4 tally with NIST values for the mass energy-absorption coefficients for air. Photon spectra were evaluated over 2 π azimuthal sampling for polar angles of 0° ≤ θ ≤ 180° every 1°. Volume averaging was averted through tight radial binning. Photon energy spectra were determined over all polar angles in both air and vacuum using

  2. The initial experience of electronic brachytherapy for the treatment of non-melanoma skin cancer

    Directory of Open Access Journals (Sweden)

    Bhatnagar Ajay

    2010-09-01

    Full Text Available Abstract Background Millions of people are diagnosed with non-melanoma skin cancers (NMSC worldwide each year. While surgical approaches are the standard treatment, some patients are appropriate candidates for radiation therapy for NMSC. High dose rate (HDR brachytherapy using surface applicators has shown efficacy in the treatment of NMSC and shortens the radiation treatment schedule by using a condensed hypofractionated approach. An electronic brachytherapy (EBT system permits treatment of NMSC without the use of a radioactive isotope. Methods Data were collected retrospectively from patients treated from July 2009 through March 2010. Pre-treatment biopsy was performed to confirm a malignant cutaneous diagnosis. A CT scan was performed to assess lesion depth for treatment planning, and an appropriate size of surface applicator was selected to provide an acceptable margin. An HDR EBT system delivered a dose of 40.0 Gy in eight fractions twice weekly with 48 hours between fractions, prescribed to a depth of 3-7 mm. Treatment feasibility, acute safety, efficacy outcomes, and cosmetic results were assessed. Results Thirty-seven patients (mean age 72.5 years with 44 cutaneous malignancies were treated. Of 44 lesions treated, 39 (89% were T1, 1 (2% Tis, 1 (2% T2, and 3 (7% lesions were recurrent. Lesion locations included the nose for 16 lesions (36.4%, ear 5 (11%, scalp 5 (11%, face 14 (32%, and an extremity for 4 (9%. Median follow-up was 4.1 months. No severe toxicities occurred. Cosmesis ratings were good to excellent for 100% of the lesions at follow-up. Conclusions The early outcomes of EBT for the treatment of NMSC appear to show acceptable acute safety and favorable cosmetic outcomes. Using a hypofractionated approach, EBT provides a convenient treatment schedule.

  3. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Science.gov (United States)

    Shi, Chengyu; Guo, Bingqi; Cheng, Chih-Yao; Eng, Tony; Papanikolaou, Nikos

    2010-09-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent™ x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  4. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos [Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, TX 78229 (United States); Cheng, Chih-Yao, E-mail: shic@uthscsa.ed [Radiation Oncology Department, Oklahoma University Health Science Center, Oklahoma, OK 73104 (United States)

    2010-09-21

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V{sub 100} reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as

  5. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    International Nuclear Information System (INIS)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos; Cheng, Chih-Yao

    2010-01-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V 100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  6. American College of Radiology-American Brachytherapy Society practice parameter for electronically generated low-energy radiation sources.

    Science.gov (United States)

    Devlin, Phillip M; Gaspar, Laurie E; Buzurovic, Ivan; Demanes, D Jeffrey; Kasper, Michael E; Nag, Subir; Ouhib, Zoubir; Petit, Joshua H; Rosenthal, Seth A; Small, William; Wallner, Paul E; Hartford, Alan C

    This collaborative practice parameter technical standard has been created between the American College of Radiology and American Brachytherapy Society to guide the usage of electronically generated low energy radiation sources (ELSs). It refers to the use of electronic X-ray sources with peak voltages up to 120 kVp to deliver therapeutic radiation therapy. The parameter provides a guideline for utilizing ELS, including patient selection and consent, treatment planning, and delivery processes. The parameter reviews the published clinical data with regard to ELS results in skin, breast, and other cancers. This technical standard recommends appropriate qualifications of the involved personnel. The parameter reviews the technical issues relating to equipment specifications as well as patient and personnel safety. Regarding suggestions for educational programs with regard to this parameter,it is suggested that the training level for clinicians be equivalent to that for other radiation therapies. It also suggests that ELS must be done using the same standards of quality and safety as those in place for other forms of radiation therapy. Copyright © 2017 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  7. Dosimetric effects of saline- versus water-filled balloon applicators for IORT using the model S700 electronic brachytherapy source.

    Science.gov (United States)

    Redler, Gage; Templeton, Alistair; Zhen, Heming; Turian, Julius; Bernard, Damian; Chu, James C H; Griem, Katherine L; Liao, Yixiang

    The Xoft Axxent Electronic Brachytherapy System (Xoft, Inc., San Jose, CA) is a viable option for intraoperative radiation therapy (IORT) treatment of early-stage breast cancer. The low-energy (50-kVp) X-ray source simplifies shielding and increases relative biological effectiveness but increases dose distribution sensitivity to medium composition. Treatment planning systems typically assume homogenous water for brachytherapy dose calculations, including precalculated atlas plans for Xoft IORT. However, Xoft recommends saline for balloon applicator filling. This study investigates dosimetric differences due to increased effective atomic number (Z eff ) for saline (Z eff  = 7.56) versus water (Z eff  = 7.42). Balloon applicator diameters range from 3 to 6 cm. Monte Carlo N-Particle software is used to calculate dose at the surface (D s ) of and 1 cm away (D 1cm ) from the water-/saline-filled balloon applicator using a single dwell at the applicator center as a simple estimation of the dosimetry and multiple dwells simulating the clinical dose distributions for the atlas plans. Single-dwell plans show a 4.4-6.1% decrease in D s for the 3- to 6-cm diameter applicators due to the saline. Multidwell plans show similar results: 4.9% and 6.4% D s decrease, for 4-cm and 6-cm diameter applicators, respectively. For the single-dwell plans, D 1cm decreases 3.6-5.2% for the 3- to 6-cm diameter applicators. For the multidwell plans, D 1cm decreases 3.3% and 5.3% for the 4-cm and 6-cm applicators, respectively. The dosimetric effect introduced by saline versus water filling for Xoft balloon applicator-based IORT treatments is ∼5%. Users should be aware of this in the context of both treatment planning and patient outcome studies. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. Surface applicator calibration and commissioning of an electronic brachytherapy system for nonmelanoma skin cancer treatment

    International Nuclear Information System (INIS)

    Rong, Yi; Welsh, James S.

    2010-01-01

    Purpose: The Xoft Axxent x-ray source has been used for treating nonmelanoma skin cancer since the surface applicators became clinically available in 2009. The authors report comprehensive calibration procedures for the electronic brachytherapy (eBx) system with the surface applicators. Methods: The Xoft miniature tube (model S700) generates 50 kVp low-energy x rays. The new surface applicators are available in four sizes of 10, 20, 35, and 50 mm in diameter. The authors' tests include measurements of dose rate, air-gap factor, output stability, depth dose verification, beam flatness and symmetry, and treatment planning with patient specific cutout factors. The TG-61 in-air method was used as a guideline for acquiring nominal dose-rate output at the skin surface. A soft x-ray parallel-plate chamber (PTW T34013) and electrometer was used for the output commissioning. GafChromic EBT films were used for testing the properties of the treatment fields with the skin applicators. Solid water slabs were used to verify the depth dose and cutout factors. Patients with basal cell or squamous cell carcinoma were treated with eBx using a calibrated Xoft system with the low-energy x-ray source and the skin applicators. Results: The average nominal dose-rate output at the skin surface for the 35 mm applicator is 1.35 Gy/min with ±5% variation for 16 sources. The dose-rate output and stability (within ±5% variation) were also measured for the remaining three applicators. For the same source, the output variation is within 2%. The effective source-surface distance was calculated based on the air-gap measurements for four applicator sizes. The field flatness and symmetry are well within 5%. Percentage depth dose in water was provided by factory measurements and can be verified using solid water slabs. Treatment duration was calculated based on the nominal dose rate, the prescription fraction size, the depth dose percentage, and the cutout factor. The output factor needs to be

  9. Surface applicator calibration and commissioning of an electronic brachytherapy system for nonmelanoma skin cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Yi; Welsh, James S. [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792 and University of Wisconsin Cancer Center-Riverview, Riverview Hospital Association, Wisconsin Rapids, Wisconsin 54494 (United States); Department of Human Oncology and Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792 and University of Wisconsin Cancer Center-Riverview, Riverview Hospital Association, Wisconsin Rapids, Wisconsin 54494 (United States)

    2010-10-15

    Purpose: The Xoft Axxent x-ray source has been used for treating nonmelanoma skin cancer since the surface applicators became clinically available in 2009. The authors report comprehensive calibration procedures for the electronic brachytherapy (eBx) system with the surface applicators. Methods: The Xoft miniature tube (model S700) generates 50 kVp low-energy x rays. The new surface applicators are available in four sizes of 10, 20, 35, and 50 mm in diameter. The authors' tests include measurements of dose rate, air-gap factor, output stability, depth dose verification, beam flatness and symmetry, and treatment planning with patient specific cutout factors. The TG-61 in-air method was used as a guideline for acquiring nominal dose-rate output at the skin surface. A soft x-ray parallel-plate chamber (PTW T34013) and electrometer was used for the output commissioning. GafChromic EBT films were used for testing the properties of the treatment fields with the skin applicators. Solid water slabs were used to verify the depth dose and cutout factors. Patients with basal cell or squamous cell carcinoma were treated with eBx using a calibrated Xoft system with the low-energy x-ray source and the skin applicators. Results: The average nominal dose-rate output at the skin surface for the 35 mm applicator is 1.35 Gy/min with {+-}5% variation for 16 sources. The dose-rate output and stability (within {+-}5% variation) were also measured for the remaining three applicators. For the same source, the output variation is within 2%. The effective source-surface distance was calculated based on the air-gap measurements for four applicator sizes. The field flatness and symmetry are well within 5%. Percentage depth dose in water was provided by factory measurements and can be verified using solid water slabs. Treatment duration was calculated based on the nominal dose rate, the prescription fraction size, the depth dose percentage, and the cutout factor. The output factor needs

  10. Surface applicator calibration and commissioning of an electronic brachytherapy system for nonmelanoma skin cancer treatment.

    Science.gov (United States)

    Rong, Yi; Welsh, James S

    2010-10-01

    The Xoft Axxent x-ray source has been used for treating nonmelanoma skin cancer since the surface applicators became clinically available in 2009. The authors report comprehensive calibration procedures for the electronic brachytherapy (eBx) system with the surface applicators. The Xoft miniature tube (model S700) generates 50 kVp low-energy x rays. The new surface applicators are available in four sizes of 10, 20, 35, and 50 mm in diameter. The authors' tests include measurements of dose rate, air-gap factor, output stability, depth dose verification, beam flatness and symmetry, and treatment planning with patient specific cutout factors. The TG-61 in-air method was used as a guideline for acquiring nominal dose-rate output at the skin surface. A soft x-ray parallel-plate chamber (PTW T34013) and electrometer was used for the output commissioning. GafChromic EBT films were used for testing the properties of the treatment fields with the skin applicators. Solid water slabs were used to verify the depth dose and cutout factors. Patients with basal cell or squamous cell carcinoma were treated with eBx using a calibrated Xoft system with the low-energy x-ray source and the skin applicators. The average nominal dose-rate output at the skin surface for the 35 mm applicator is 1.35 Gy/min with +/- 5% variation for 16 sources. The dose-rate output and stability (within +/- 5% variation) were also measured for the remaining three applicators. For the same source, the output variation is within 2%. The effective source-surface distance was calculated based on the air-gap measurements for four applicator sizes. The field flatness and symmetry are well within 5%. Percentage depth dose in water was provided by factory measurements and can be verified using solid water slabs. Treatment duration was calculated based on the nominal dose rate, the prescription fraction size, the depth dose percentage, and the cutout factor. The output factor needs to be measured for each case with

  11. A comparison of the relative biological effectiveness of low energy electronic brachytherapy sources in breast tissue: a Monte Carlo study.

    Science.gov (United States)

    White, Shane A; Reniers, Brigitte; de Jong, Evelyn E C; Rusch, Thomas; Verhaegen, Frank

    2016-01-07

    Electronic brachytherapy sources use low energy photons to treat the tumor bed during or after breast-conserving surgery. The relative biological effectiveness of two electronic brachytherapy sources was explored to determine if spectral differences due to source design influenced radiation quality and if radiation quality decreased with distance in the breast. The RBE was calculated through the number of DNA double strand breaks (RBEDSB) using the Monte Carlo damage simulator (MCDS) in combination with other Monte Carlo electron/photon spectrum calculations. 50kVp photons from the Intrabeam (Carl Zeiss Surgical) and Axxent (Xoft) through 40-mm spherical applicators were simulated to account for applicator and tissue attenuation in a variety of breast tissue compositions. 40kVp Axxent photons were also simulated. Secondary electrons (known to be responsible for most DNA damage) spectra at different distance were inputted into MCDS to calculate the RBEDSB. All RBEDSB used a cobalt-60 reference. RBEDSB data was combined with corresponding average photon spectrum energy for the Axxent and applied to model-based average photon energy distributions to produce an RBEDSB map of an accelerated partial breast irradiation (APBI) patient. Both Axxent and Intrabeam 50kVp spectra were shown to have a comparable RBEDSB of between 1.4 and 1.6 at all distances in spite of progressive beam hardening. The Axxent 40kVp also demonstrated a similar RBEDSB at distances. Most RBEDSB variability was dependent on the tissue type as was seen in rib (RBEDSB  ≈  1.4), gland (≈1.55), adipose (≈1.59), skin (≈1.52) and lung (≈1.50). RBEDSB variability between both sources was within 2%. A correlation was shown between RBEDSB and average photon energy and used to produce an RBEDSB map of a dose distribution in an APBI patient dataset. Radiation quality is very similar between electronic brachytherapy sources studied. No significant reductions in RBEDSB were observed with

  12. SU-E-T-284: Revisiting Reference Dosimetry for the Model S700 Axxent 50 KVp Electronic Brachytherapy Source

    International Nuclear Information System (INIS)

    Hiatt, JR; Rivard, MJ

    2014-01-01

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft was characterized in 2006 by Rivard et al. The source design was modified in 2006 to include a plastic centering insert at the source tip to more accurately position the anode. The objectives of the current study were to establish an accurate Monte Carlo source model for simulation purposes, to dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and to determine dose differences between the source with and without the centering insert. Methods: Design information from dissected sources and vendor-supplied CAD drawings were used to devise the source model for radiation transport simulations of dose distributions in a water phantom. Collision kerma was estimated as a function of radial distance, r, and polar angle, θ, for determination of reference TG-43 dosimetry parameters. Simulations were run for 10 10 histories, resulting in statistical uncertainties on the transverse plane of 0.03% at r=1 cm and 0.08% at r=10 cm. Results: The dose rate distribution the transverse plane did not change beyond 2% between the 2006 model and the current study. While differences exceeding 15% were observed near the source distal tip, these diminished to within 2% for r>1.5 cm. Differences exceeding a factor of two were observed near θ=150° and in contact with the source, but diminished to within 20% at r=10 cm. Conclusions: Changes in source design influenced the overall dose rate and distribution by more than 2% over a third of the available solid angle external from the source. For clinical applications using balloons or applicators with tissue located within 5 cm from the source, dose differences exceeding 2% were observed only for θ>110°. This study carefully examined the current source geometry and presents a modern reference TG-43 dosimetry dataset for the model S700 source

  13. Surgical perspectives from a prospective, nonrandomized, multicenter study of breast conserving surgery and adjuvant electronic brachytherapy for the treatment of breast cancer

    Directory of Open Access Journals (Sweden)

    Beatty J David

    2011-03-01

    Full Text Available Abstract Background Accelerated partial breast irradiation (APBI may be used to deliver radiation to the tumor bed post-lumpectomy in eligible patients with breast cancer. Patient and tumor characteristics as well as the lumpectomy technique can influence patient eligibility for APBI. This report describes a lumpectomy procedure and examines patient, tumor, and surgical characteristics from a prospective, multicenter study of electronic brachytherapy. Methods The study enrolled 65 patients of age 45-84 years with ductal carcinoma or ductal carcinoma in situ, and 44 patients, who met the inclusion and exclusion criteria, were treated with APBI using the Axxent® electronic brachytherapy system following lumpectomy. The prescription dose was 34 Gy in 10 fractions over 5 days. Results The lumpectomy technique as described herein varied by site and patient characteristics. The balloon applicator was implanted by the surgeon (91% or a radiation oncologist (9% during or up to 61 days post-lumpectomy (mean 22 days. A lateral approach was most commonly used (59% for insertion of the applicator followed by an incision site approach in 27% of cases, a medial approach in 5%, and an inferior approach in 7%. A trocar was used during applicator insertion in 27% of cases. Local anesthetic, sedation, both or neither were administered in 45%, 2%, 41% and 11% of cases, respectively, during applicator placement. The prescription dose was delivered in 42 of 44 treated patients. Conclusions Early stage breast cancer can be treated with breast conserving surgery and APBI using electronic brachytherapy. Treatment was well tolerated, and these early outcomes were similar to the early outcomes with iridium-based balloon brachytherapy.

  14. SU-F-T-45: Dosimetric Effects of Saline Filled Balloons During IORT Using Xoft Electronic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Redler, G; Templeton, A; Turian, J; Chu, J; Bernard, D; Zhen, H; Liao, Y [Rush University Medical Center, Chicago, IL (United States)

    2016-06-15

    Purpose: The portability of Xoft Axxent Electronic Brachytherapy (EBx) System has made it a viable option for intraoperative radiation therapy (IORT) treatment of early-stage breast cancer. The low energy (50kVp) of the X-ray source makes the shielding easy, but also means its dose distribution is sensitive to the medium’s composition. Current treatment planning systems (TPS) typically assume homogenous water for brachytherapy dose calculations, including the pre-calculated atlas plans for the Xoft IORT cases. However, Xoft recommends using saline to fill the balloon applicator. This study investigates the dosimetric difference due to the increased effective atomic number (Zeff) from water (7.42) to saline (7.56). Methods: The diameter of the balloon applicators ranges from 3–6cm, with 4cm being most frequently used. For the 4-cm and 6-cm diameter applicators, MCNP Monte Carlo program was used to calculate the dose at the surface (Ds) of the middle section of the balloon and 1 cm away (D1cm) for water- and saline-filled balloons: one plan with a single dwell at the center and another with multiple dwells as in the atlas plans. The single dwell plan is a simple estimation of the dosimetry, while the atlas plan is representative of the actual dose distribution. Results: The single-dwell plan showed a 5.1% and 6.1% decrease in Ds for the 4- and 6-cm applicators, respectively, due to the saline. The atlas plan showed similar Results: 4.8% and 6.4% decrease, respectively. The decrease in D1cm is 4.3%–5.2% and 3.3%–5.3s% in the single-dwell and atlas plans, respectively, for the 4- and 6-cm applicator. Conclusion: The dosimetric effect introduced by saline is on the order of 5%. This effect should be taken into account during both treatment planning and patient outcome studies.

  15. Post operative high dose rate intravaginal irradiation in endometrial cancer: a safe and effective outpatient treatment

    International Nuclear Information System (INIS)

    Chen, Peter; Gibbons, Susan; Vicini, Frank; Weiner, Sheldon; Dmuchowski, Carl; Mele, Beth; Brabbins, Donald; Jennings, John; Gustafson, Gary; Martinez, Alvaro

    1995-01-01

    Purpose: We reviewed our experience with out patient high dose rate (HDR) intravaginal irradiation given post-operatively in endometrial cancer to assess local control, survival, and toxicity when used alone or in combination with external beam irradiation. Methods and Materials: From (12(88)) to (12(92)), 78 patients underwent TAH/BSO and received post-operative HDR intravaginal irradiation for endometrial cancer. Pathologic stage distribution was IB/IC: 56%, II: 22%, III: 22%. Adjuvant therapy was given in one of three schemes: HDR vaginal radiation alone (6 weekly fractions of 500 cGy prescribed 5 mm from the applicator surface treating the upper 4 cm of the vagina), pelvic irradiation with vaginal HDR (500 cGy x 4 weekly fractions) or whole abdomen/pelvic irradiation (WAPI) with vaginal HDR treatment (500 cGy x 3 weekly fractions). Prior to the first HDR vaginal treatment, a simulation with placement of vaginal apex metallic markers was performed to assure proper positioning of the intravaginal cylinders. Pelvic midline blocking was designed from the HDR intravaginal simulation films. The 55 patients who underwent combined external beam irradiation/brachytherapy received a median dose to the pelvis of 5040 cGy (range 25.2-51.6 Gy), and a median total vaginal dose of 5060 cGy (range 30.0-57.6 Gy). Results: Median follow-up is 37 months (range 6-73 months). Local control (vaginally) is 98.7%. The one vaginal failure was in the distal vagina, outside the treatment volume. All other failures (4) were distant with the vagina controlled [3 intra-abdominal and one bone/intra-abdominal]. For stages I and II, the disease free survival is 92.8%. For stage III the disease free survival is 86.5%. Median overall time to failure is 14.3 months (range 8.5-18.6 months). In terms of acute toxicity, no grade 3-4 acute toxicity of the vagina or bladder was seen. However, 9% acute GI toxicity was encountered. Chronic grade 1-2 toxicities included: vaginal 21.8% (foreshortening and

  16. SU-F-T-234: Quality Improvements in the Electronic Medical Record of Patients Treated with High Dose-Rate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Diener, T [Cleveland State University, Cleveland, OH (United States); Wilkinson, D [Cleveland Clinic Foundation, Cleveland, OH (United States)

    2016-06-15

    Purpose: To improve workflow efficiency and patient safety by assessing the quality control documentation for HDR brachytherapy within our Electronic Medical Record System (Mosaiq). Methods: A list of parameters based on NRC regulations, our quality management program (QMP), recommendations of the ACR and the American Brachytherapy Society, and HDR treatment planning risks identified in our previous FMEA study was made. Next, the parameter entries were classified according to the type of data input—manual, electronic, or both. Manual entry included the electronic Brachytherapy Treatment Record (BTR) and pre-treatment Mosaiq Assessments list. Oncentra Treatment Reports (OTR) from the Oncentra Treatment Control System constituted the electronic data. The OTR includes a Pre-treatment Report for each fraction, and a Treatment Summary Report at the completion of treatment. Each entry was then examined for appropriateness and completeness of data; adjustments and additions as necessary were then made. Results: Ten out of twenty-one recorded treatment parameters were identified to be documented within both the BTR and OTR. Of these ten redundancies, eight were changed from recorded values to a simple checklist in the BTR to avoid recording errors. The other redundancies were kept in both documents due to their value to ensuring patient safety. An edit was made to the current BTR quality assessment; this change revises the definition of a medical event in accordance with ODH Regulation 3701:1-58-101. One addition was made to the current QMP documents regarding HDR. This addition requires a physician to be present through the duration of HDR treatment in accordance with ODH Regulation 3701:1-58-59; Paragraph (F); Section (2); Subsection (a). Conclusion: Careful examination of HDR documentation that originates from different sources can help to improve the accuracy and reliability of the documents. In addition, there may be a small improvement in efficiency due to

  17. SU-E-T-387: Evaluation of Effective Treatment Depth in Skin Cancer Treatments with Xoft Electronic Brachytherapy

    International Nuclear Information System (INIS)

    Dragojevic, I; Hoisak, J

    2015-01-01

    Purpose: To evaluate changes in the percent depth dose (PDD) and effective depth of treatment based on exerted force by applicator on the skin during treatments of skin cancer with Xoft Electronic Brachytherapy. Methods: To simulate compressible tissue, 5mm tissue-equivalent bolus was used. An ion chamber (Soft X-ray Chamber, PTW) and electrometer (Max 4000, Standard Imaging) were used for output measurements. Measurements were done for all available Xoft surface applicators (10, 20, 35, and 50mm cones) with plastic endcap. Fig1 shows the experimental setup. The PDD was measured first with no or minimal pressure of the applicator on the bolus, followed by increasing uniform pressure on the applicator applied with custom cerrobend weights. The measurements were used to calculate the effective PDD and effective depth. Results: Force applied with the applicator was plotted against the change in PDD relative to the PDD when no force is applied. For the 10mm cone, moderate force of 5N can change the PDD by more than 20%, (Fig2). The effect is also pronounced for the 20mm cone, while it is minimal for the 35 and 50mm cones. Even when only moderate force is applied, the effective prescription depth can be changed by a several millimeters, which is on the order of the typical prescription depth (Fig3). Conclusion: Based on the results of this simulation, excessive pressure applied on the patient’s skin by the applicator cone can drastically alter the PDD and effective treatment depth. The effect is most pronounced for the 10mm cone, and to a lesser extent, 20mm, which is significant as these cones tend to be used most frequently in the clinic. Applicator placement therefore may Result in significant consequences such as excessive dose to target, severe skin reaction, permanent discoloration, skin indentation, and poor overall cosmesis upon completion of treatment

  18. Dose modeling of noninvasive image-guided breast brachytherapy in comparison to electron beam boost and three-dimensional conformal accelerated partial breast irradiation.

    Science.gov (United States)

    Sioshansi, Shirin; Rivard, Mark J; Hiatt, Jessica R; Hurley, Amanda A; Lee, Yoojin; Wazer, David E

    2011-06-01

    To perform dose modeling of a noninvasive image-guided breast brachytherapy (NIIGBB) for comparison to electrons and 3DCRT. The novel technology used in this study is a mammography-based, noninvasive breast brachytherapy system whereby the treatment applicators are centered on the planning target volume (PTV) to direct (192)Ir emissions along orthogonal axes. To date, three-dimensional dose modeling of NIIGBB has not been possible because of the limitations of conventional treatment planning systems (TPS) to model variable tissue deformation associated with breast compression. In this study, the TPS was adapted such that the NIIGBB dose distributions were modeled as a virtual point source. This dose calculation technique was applied to CT data from 8 patients imaged with the breast compressed between parallel plates in the cranial-caudal and medial-lateral axes. A dose-volume comparison was performed to simulated electron boost and 3DCRT APBI. The NIIGBB PTV was significantly reduced as compared with both electrons and 3DCRT. Electron boost plans had a lower D(min) than the NIIGBB technique but higher V(100), D(90), and D(50). With regard to PTV coverage for APBI, the only significant differences were minimally higher D(90), D(100), V(80), and V(90), with 3DCRT and D(max) with NIIGBB. The NIIGBB technique, as compared with electrons and 3D-CRT, achieved a lower maximum dose to skin (60% and 10%, respectively) and chest wall/lung (70-90%). NIIGBB achieves a PTV that is smaller than electron beam and 3DCRT techniques. This results in significant normal tissue sparing while maintaining dosimetric benchmarks to the target tissue. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Intravascular brachytherapy for peripheral vascular disease

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2008-09-01

    Full Text Available Scientific background: Percutaneous transluminal angioplasties (PTA through balloon dilatation with or without stenting, i.e. vessel expansion through balloons with or without of implantation of small tubes, called stents, are used in the treatment of peripheral artery occlusive disease (PAOD. The intravascular vessel irradiation, called intravascular brachytherapy, promises a reduction in the rate of repeated stenosis (rate of restenosis after PTA. Research questions: The evaluation addresses questions on medical efficacy, cost-effectiveness as well as ethic, social and legal implications in the use of brachytherapy in PAOD patients. Methods: A systematic literature search was conducted in August 2007 in the most important medical electronic databases for publications beginning from 2002. The medical evaluation included randomized controlled trials (RCT. The information synthesis was performed using meta-analysis. Health economic modeling was performed with clinical assumptions derived from the meta-analysis and economical assumptions derived from the German Diagnosis Related Groups (G-DRG-2007. Results: Medical evaluation: Twelve publications about seven RCT on brachytherapy vs. no brachytherapy were included in the medical evaluation. Two RCT showed a significant reduction in the rate of restenosis at six and/or twelve months for brachytherapy vs. no brachytherapy after successful balloon dilatation, the relative risk in the meta-analysis was 0.62 (95% CI: 0.46 to 0.84. At five years, time to recurrence of restenosis was significantly delayed after brachytherapy. One RCT showed a significant reduction in the rate of restenosis at six months for brachytherapy vs. no brachytherapy after PTA with optional stenting, the relative risk in the meta-analysis was 0.76 (95% CI: 0.61 to 0.95. One RCT observed a significantly higher rate of late thrombotic occlusions after brachytherapy in the subgroup of stented patients. A single RCT for brachytherapy

  20. [Rehabilitation for intravaginal ejaculatory dysfunction with using a masturbation aid].

    Science.gov (United States)

    Kobori, Yoshitomo; Aoki, Hiroaki; Nishio, Koujiro; Sato, Ryo; Ashizawa, Yoshio; Yagi, Hiroshi; So, Shigehiro; Arai, Gaku; Okada, Hiroshi

    2012-05-01

    Recently the incidence of intravaginal ejaculatory dysfunction is increasing among infertile couples in Japan. Some unusual ways of masturbation and psychogenic issues were reported to cause this disorder. Patients, who had done masturbation in an unusual way for long time since their adolescence, were difficult to gain normal intravaginal ejaculation by the behavior therapy which was used for erectile dysfunction. We, therefore, used a masturbation aid (TENGA) for rehabilitation of ejaculation to overcome this condition. From January, 2010 through March, 2011, a total of 16 patients with intravaginal ejaculatory dysfunction underwent rehabilitation of ejaculation using TENGA. Patients' satisfaction and achievement of intravaginal ejaculation were evaluated by the questionnaire. Twelve patients (75%) could ejaculate in the masturbation aid (TENGA). Five patients (31%) succeeded to ejaculate in the partner's vagina after rehabilitation. A masturbation aid (TENGA) was a useful tool to correct the way of masturbation and achieve normal intravaginal ejaculation. This masturbation aid can be one of the effective options for the treatment of intravaginal ejaculatory dysfunction.

  1. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    International Nuclear Information System (INIS)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte; Fonseca, Gabriel Paiva; Holt, Randy; Rusch, Thomas; Beaulieu, Luc; Verhaegen, Frank

    2014-01-01

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy ( w,m ) and dose to medium (D m,m ), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D 90 to PTV was reduced by between ∼4% and ∼40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose is also reduced by 10%–15% due to the absence of backscatter not accounted for in TG-43. The balloon applicator also contributed to the reduced dose. Other ROIs showed a difference depending on the method of dose reporting. Conclusions: TG-186-based calculations produce results that are different from TG-43 for the Axxent source. The differences depend strongly on the method of dose reporting. This study highlights the importance of backscatter to peak skin dose. Tissue heterogeneities, applicator, and patient geometries demonstrate the need for a more robust dose calculation method for low energy brachytherapy sources

  2. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte, E-mail: brigitte.reniers@maastro.nl [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN (Netherlands); Fonseca, Gabriel Paiva [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP, São Paulo CP 11049, 05422-970 (Brazil); Holt, Randy; Rusch, Thomas [Xoft, A Subsidiary of iCAD, Sunnyvale, California 94085-4115 (United States); Beaulieu, Luc [Centre Hospitalier Universitaire de Québec Université Laval, Radio-Oncologie et Centre de Recherche en Cancérologie de l’Université Laval, Québec, Québec G1R 2J6 Canada (Canada); Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Department of Oncology, McGill University, Montreal, Quebec H3G 1A4 (Canada)

    2014-06-15

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (<50 kV) brachytherapy system used in accelerated partial breast irradiation (APBI). Breast tissue is a heterogeneous tissue in terms of density and composition. Dosimetric calculations of seven APBI patients treated with Axxent were made using a model-based Monte Carlo platform for a number of tissue models and dose reporting methods and compared to TG-43 based plans. Methods: A model of the Axxent source, the S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (D{sub w,m}) and dose to medium (D{sub m,m}), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D{sub 90} to PTV was reduced by between ∼4% and ∼40%, depending on the

  3. Characteristics of miniature electronic brachytherapy x-ray sources based on TG-43U1 formalism using Monte Carlo simulation techniques

    International Nuclear Information System (INIS)

    Safigholi, Habib; Faghihi, Reza; Jashni, Somaye Karimi; Meigooni, Ali S.

    2012-01-01

    Purpose: The goal of this study is to determine a method for Monte Carlo (MC) characterization of the miniature electronic brachytherapy x-ray sources (MEBXS) and to set dosimetric parameters according to TG-43U1 formalism. TG-43U1 parameters were used to get optimal designs of MEBXS. Parameters that affect the dose distribution such as anode shapes, target thickness, target angles, and electron beam source characteristics were evaluated. Optimized MEBXS designs were obtained and used to determine radial dose functions and 2D anisotropy functions in the electron energy range of 25-80 keV. Methods: Tungsten anode material was considered in two different geometries, hemispherical and conical-hemisphere. These configurations were analyzed by the 4C MC code with several different optimization techniques. The first optimization compared target thickness layers versus electron energy. These optimized thicknesses were compared with published results by Ihsan et al.[Nucl. Instrum. Methods Phys. Res. B 264, 371-377 (2007)]. The second optimization evaluated electron source characteristics by changing the cathode shapes and electron energies. Electron sources studied included; (1) point sources, (2) uniform cylinders, and (3) nonuniform cylindrical shell geometries. The third optimization was used to assess the apex angle of the conical-hemisphere target. The goal of these optimizations was to produce 2D-dose anisotropy functions closer to unity. An overall optimized MEBXS was developed from this analysis. The results obtained from this model were compared to known characteristics of HDR 125 I, LDR 103 Pd, and Xoft Axxent electronic brachytherapy source (XAEBS) [Med. Phys. 33, 4020-4032 (2006)]. Results: The optimized anode thicknesses as a function of electron energy is fitted by the linear equation Y (μm) = 0.0459X (keV)-0.7342. The optimized electron source geometry is obtained for a disk-shaped parallel beam (uniform cylinder) with 0.9 mm radius. The TG-43 distribution

  4. Characteristics of miniature electronic brachytherapy x-ray sources based on TG-43U1 formalism using Monte Carlo simulation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Safigholi, Habib; Faghihi, Reza; Jashni, Somaye Karimi; Meigooni, Ali S. [Faculty of Engineering, Science and Research Branch, Islamic Azad University, Fars, 73481-13111, Persepolis (Iran, Islamic Republic of); Department of Nuclear Engineering and Radiation Research Center, Shiraz University, 71936-16548, Shiraz (Iran, Islamic Republic of); Shiraz University of Medical Sciences, 71348-14336, Shiraz (Iran, Islamic Republic of); Department of Radiation therapy, Comprehensive Cancer Center of Nevada, 3730 South Eastern Avenue, Las Vegas, Nevada 89169 (United States)

    2012-04-15

    Purpose: The goal of this study is to determine a method for Monte Carlo (MC) characterization of the miniature electronic brachytherapy x-ray sources (MEBXS) and to set dosimetric parameters according to TG-43U1 formalism. TG-43U1 parameters were used to get optimal designs of MEBXS. Parameters that affect the dose distribution such as anode shapes, target thickness, target angles, and electron beam source characteristics were evaluated. Optimized MEBXS designs were obtained and used to determine radial dose functions and 2D anisotropy functions in the electron energy range of 25-80 keV. Methods: Tungsten anode material was considered in two different geometries, hemispherical and conical-hemisphere. These configurations were analyzed by the 4C MC code with several different optimization techniques. The first optimization compared target thickness layers versus electron energy. These optimized thicknesses were compared with published results by Ihsan et al.[Nucl. Instrum. Methods Phys. Res. B 264, 371-377 (2007)]. The second optimization evaluated electron source characteristics by changing the cathode shapes and electron energies. Electron sources studied included; (1) point sources, (2) uniform cylinders, and (3) nonuniform cylindrical shell geometries. The third optimization was used to assess the apex angle of the conical-hemisphere target. The goal of these optimizations was to produce 2D-dose anisotropy functions closer to unity. An overall optimized MEBXS was developed from this analysis. The results obtained from this model were compared to known characteristics of HDR {sup 125}I, LDR {sup 103}Pd, and Xoft Axxent electronic brachytherapy source (XAEBS) [Med. Phys. 33, 4020-4032 (2006)]. Results: The optimized anode thicknesses as a function of electron energy is fitted by the linear equation Y ({mu}m) = 0.0459X (keV)-0.7342. The optimized electron source geometry is obtained for a disk-shaped parallel beam (uniform cylinder) with 0.9 mm radius. The TG-43

  5. SU-E-T-284: Revisiting Reference Dosimetry for the Model S700 Axxent 50 KV{sub p} Electronic Brachytherapy Source

    Energy Technology Data Exchange (ETDEWEB)

    Hiatt, JR [Rhode Island Hospital, Providence, RI (United States); Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States)

    2014-06-01

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft was characterized in 2006 by Rivard et al. The source design was modified in 2006 to include a plastic centering insert at the source tip to more accurately position the anode. The objectives of the current study were to establish an accurate Monte Carlo source model for simulation purposes, to dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and to determine dose differences between the source with and without the centering insert. Methods: Design information from dissected sources and vendor-supplied CAD drawings were used to devise the source model for radiation transport simulations of dose distributions in a water phantom. Collision kerma was estimated as a function of radial distance, r, and polar angle, θ, for determination of reference TG-43 dosimetry parameters. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.03% at r=1 cm and 0.08% at r=10 cm. Results: The dose rate distribution the transverse plane did not change beyond 2% between the 2006 model and the current study. While differences exceeding 15% were observed near the source distal tip, these diminished to within 2% for r>1.5 cm. Differences exceeding a factor of two were observed near θ=150° and in contact with the source, but diminished to within 20% at r=10 cm. Conclusions: Changes in source design influenced the overall dose rate and distribution by more than 2% over a third of the available solid angle external from the source. For clinical applications using balloons or applicators with tissue located within 5 cm from the source, dose differences exceeding 2% were observed only for θ>110°. This study carefully examined the current source geometry and presents a modern reference TG-43 dosimetry dataset for the model S700 source.

  6. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source.

    Science.gov (United States)

    White, Shane A; Landry, Guillaume; Fonseca, Gabriel Paiva; Holt, Randy; Rusch, Thomas; Beaulieu, Luc; Verhaegen, Frank; Reniers, Brigitte

    2014-06-01

    The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (Dw,m) and dose to medium (Dm,m), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D90 to PTV was reduced by between ~4% and ~40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose is also reduced by 10%-15% due to the absence of backscatter not accounted for in TG-43. The balloon applicator also contributed to the reduced dose. Other ROIs showed a difference depending on the method of dose reporting. TG-186-based calculations produce results that are different from TG-43 for the Axxent source. The differences depend strongly on the method of dose reporting. This study

  7. Urethral dose sparing in squamous cell carcinoma of anal canal using proton therapy matching electrons with prior brachytherapy for prostate cancer: A case study.

    Science.gov (United States)

    Apinorasethkul, Ontida; Lenards, Nishele; Hunzeker, Ashley

    2016-01-01

    The purpose of this case study is to communicate a technique on treating the re-irradiation of squamous cell carcinoma (SCC) of anal canal with proton fields matched with electron fields to spare prostatic urethra. A 76-year old male presented with a secondary radiation-induced malignancy as a result of prostate brachytherapy seeds irradiation 10 years prior. A rectal examination revealed a bulky tumor at the top of the anal canal involving the left superior-most aspect of the anal canal extending superiorly into the rectum. The inferior extent was palpable approximately 3cm from the anal verge and the superior extent of the mass measured greater than 5cm in the superior-inferior dimension. Chemoradiation was suggested since the patient was opposed to abdominoperineal resection (APR) and colostomy. The use of proton therapy matching with electron fields in the re-irradiation setting could help reduce the complications. A 2 lateral proton beams were designed to treat the bulky tumor volume with 2 electron beams treating the nodal volumes. This complication of treatment fields helped spare the prostatic urethra and reduced the risk of urinary obstruction in the future. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  8. Urethral dose sparing in squamous cell carcinoma of anal canal using proton therapy matching electrons with prior brachytherapy for prostate cancer: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Apinorasethkul, Ontida, E-mail: ontida.a@gmail.com [Medical Dosimetry Graduate Program, University of Wisconsin, La Crosse, WI (United States); Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Lenards, Nishele; Hunzeker, Ashley [Medical Dosimetry Graduate Program, University of Wisconsin, La Crosse, WI (United States)

    2016-10-01

    The purpose of this case study is to communicate a technique on treating the re-irradiation of squamous cell carcinoma (SCC) of anal canal with proton fields matched with electron fields to spare prostatic urethra. A 76-year old male presented with a secondary radiation-induced malignancy as a result of prostate brachytherapy seeds irradiation 10 years prior. A rectal examination revealed a bulky tumor at the top of the anal canal involving the left superior-most aspect of the anal canal extending superiorly into the rectum. The inferior extent was palpable approximately 3 cm from the anal verge and the superior extent of the mass measured greater than 5 cm in the superior-inferior dimension. Chemoradiation was suggested since the patient was opposed to abdominoperineal resection (APR) and colostomy. The use of proton therapy matching with electron fields in the re-irradiation setting could help reduce the complications. A 2 lateral proton beams were designed to treat the bulky tumor volume with 2 electron beams treating the nodal volumes. This complication of treatment fields helped spare the prostatic urethra and reduced the risk of urinary obstruction in the future.

  9. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy.

    Science.gov (United States)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-09

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR (192)Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR (192)Ir brachytherapy.

  10. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy

    International Nuclear Information System (INIS)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-01

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR 192 Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR 192 Ir brachytherapy

  11. Adherence to Vaginal Dilation Following High Dose Rate Brachytherapy for Endometrial Cancer

    International Nuclear Information System (INIS)

    Friedman, Lois C.; Abdallah, Rita; Schluchter, Mark; Panneerselvam, Ashok; Kunos, Charles A.

    2011-01-01

    Purpose: We report demographic, clinical, and psychosocial factors associated with adherence to vaginal dilation and describe the sexual and marital or nonmarital dyadic functioning of women following high dose rate (HDR) brachytherapy for endometrial cancer. Methods and Materials: We retrospectively evaluated women aged 18 years or older in whom early-stage endometrial (IAgr3-IIB) cancers were treated by HDR intravaginal brachytherapy within the past 3.5 years. Women with or without a sexual partner were eligible. Patients completed questionnaires by mail or by telephone assessing demographic and clinical variables, adherence to vaginal dilation, dyadic satisfaction, sexual functioning, and health beliefs. Results: Seventy-eight of 89 (88%) eligible women with early-stage endometrial cancer treated with HDR brachytherapy completed questionnaires. Only 33% of patients were adherers, based on reporting having used a dilator more than two times per week in the first month following radiation. Nonadherers who reported a perceived change in vaginal dimension following radiation reported that their vaginas were subjectively smaller after brachytherapy (p = 0.013). Adherers reported more worry about their sex lives or lack thereof than nonadherers (p = 0.047). Patients reported considerable sexual dysfunction following completion of HDR brachytherapy. Conclusions: Adherence to recommendations for vaginal dilator use following HDR brachytherapy for endometrial cancer is poor. Interventions designed to educate women about dilator use benefit may increase adherence. Although sexual functioning was compromised, it is likely that this existed before having cancer for many women in our study.

  12. Radiotherapy and brachytherapy

    International Nuclear Information System (INIS)

    2007-02-01

    This presentation first defines the radiotherapy and brachytherapy techniques, indicates the used ionizing radiations (electromagnetic and particles), describes the mechanisms and processes of action of ionizing radiations: they can be physical by photon-matter interactions (Compton effect and photoelectric effect) or due to electron-matter interactions (excitation, ionization), physical-chemical by direct or indirect action (DNA damage), cellular (mitotic or apoptotic death), tissue (sane and tumorous tissues and differential effect). It discusses the biological efficiency of these treatments which depends on different parameters: intrinsic radio-sensitivity, time (session fractioning and organisation in time), oxygen, radiation quality, cellular cycle, dose rate, temperature. It presents the different types of radiotherapy: external radiotherapy (general sequence, delineation, dosimetry, protection of critical organs, treatment session, quality control, monitoring consultation) and briefly presents some specific techniques (total body irradiation, total cutaneous electron therapy, pre-operation radiotherapy, radio-surgery, hadron-therapy). It proposes an overview of the main indications for this treatment: brain tumours, upper aero digestive tract tumours, bronchial tumours, oesophagus, stomach and pancreas tumours, breast tumours, cervix cancer, rectum tumour, and so on, and indicates the possible associated treatments. The next part addresses brachytherapy. It presents the principles and comments the differences with radiotherapy. It indicates the used radio-elements (Caesium 137, Iridium 192, Iodine 125), describes the implementation techniques (plastic tubes, use of iodine 125, intracavitary and endo-luminal radiation therapy). It proposes an overview of the different treated tumours (skin, breast, prostates, bronchial, oesophagus, ENT) and indicates possible early and late secondary effects for different organs

  13. Prostate cancer brachytherapy

    International Nuclear Information System (INIS)

    Abreu, Carlos Eduardo Vita; Silva, Joao L. F.; Srougi, Miguel; Nesrallah, Adriano

    1999-01-01

    The transperineal brachytherapy with 125 I/Pd 103 seed implantation guided by transurethral ultrasound must be presented as therapeutical option of low urinary morbidity in patients with localized prostate cancer. The combined clinical staging - including Gleason and initial PSA - must be encouraged, for definition of a group of low risk and indication of exclusive brachytherapy. Random prospective studies are necessary in order to define the best role of brachytherapy, surgery and external beam radiation therapy

  14. Prostate brachytherapy - discharge

    Science.gov (United States)

    Implant therapy - prostate cancer - discharge; Radioactive seed placement - discharge ... You had a procedure called brachytherapy to treat prostate cancer. Your treatment lasted 30 minutes or more, ...

  15. Outcome of treatment of upper third vaginal recurrences of cervical and endometrial carcinomas with interstitial brachytherapy

    International Nuclear Information System (INIS)

    Charra, C.; Roy, P.; Coquard, R.; Romestaing, P.; Ardiet, J.M.; Gerard, J.P.

    1998-01-01

    Purpose: To describe an original brachytherapy technique using a dedicated intravaginal template for the treatment of vaginal vault recurrences and to evaluate the results of such a treatment. Methods and Materials: Between 1978 and 1993, 78 patients with isolated recurrence of cervical or endometrial carcinoma located in the vaginal vault have been treated in Lyon. Initial treatment was surgery alone in 49 cases and irradiation with surgery in 37 cases. Treatment of the vaginal recurrence was performed with interstitial Iridium 192 brachytherapy combined with pelvic external beam radiation therapy in 34 patients. The tumor was implanted with a dedicated intravaginal plastic template. Six parallel metallic needles were implanted in the vaginal vault and afterloaded with Iridium 192 wires of 4 to 6 cm long. The mucosa of the upper half of the vagina received the same dose as the one encompassing the tumor on the 85% isodose of the Paris system. Results: At 5 years the local control rate was 70% and the overall survival rate 56%. Grade 3 complications occurred in 10% of the cases and only in patients who had received irradiation during the initial treatment of the primary tumor. Conclusions: This brachytherapy technique makes it possible to perform Iridium 192 implants in a difficult situation with a favorable long-term control rate and an acceptable rate of complications

  16. Advancements in brachytherapy

    DEFF Research Database (Denmark)

    Tanderup, Kari; Ménard, Cynthia; Polgar, Csaba

    2017-01-01

    Brachytherapy is a radiotherapy modality associated with a highly focal dose distribution. Brachytherapy treats the cancer tissue from the inside, and the radiation does not travel through healthy tissue to reach the target as with external beam radiotherapy techniques. The nature of brachytherap...

  17. SU-E-T-421: Failure Mode and Effects Analysis (FMEA) of Xoft Electronic Brachytherapy for the Treatment of Superficial Skin Cancers

    International Nuclear Information System (INIS)

    Hoisak, J; Manger, R; Dragojevic, I

    2015-01-01

    Purpose: To perform a failure mode and effects analysis (FMEA) of the process for treating superficial skin cancers with the Xoft Axxent electronic brachytherapy (eBx) system, given the recent introduction of expanded quality control (QC) initiatives at our institution. Methods: A process map was developed listing all steps in superficial treatments with Xoft eBx, from the initial patient consult to the completion of the treatment course. The process map guided the FMEA to identify the failure modes for each step in the treatment workflow and assign Risk Priority Numbers (RPN), calculated as the product of the failure mode’s probability of occurrence (O), severity (S) and lack of detectability (D). FMEA was done with and without the inclusion of recent QC initiatives such as increased staffing, physics oversight, standardized source calibration, treatment planning and documentation. The failure modes with the highest RPNs were identified and contrasted before and after introduction of the QC initiatives. Results: Based on the FMEA, the failure modes with the highest RPN were related to source calibration, treatment planning, and patient setup/treatment delivery (Fig. 1). The introduction of additional physics oversight, standardized planning and safety initiatives such as checklists and time-outs reduced the RPNs of these failure modes. High-risk failure modes that could be mitigated with improved hardware and software interlocks were identified. Conclusion: The FMEA analysis identified the steps in the treatment process presenting the highest risk. The introduction of enhanced QC initiatives mitigated the risk of some of these failure modes by decreasing their probability of occurrence and increasing their detectability. This analysis demonstrates the importance of well-designed QC policies, procedures and oversight in a Xoft eBx programme for treatment of superficial skin cancers. Unresolved high risk failure modes highlight the need for non-procedural quality

  18. SU-F-BRA-09: New Efficient Method for Xoft Axxent Electronic Brachytherapy Source Calibration by Pre-Characterizing Surface Applicators

    Energy Technology Data Exchange (ETDEWEB)

    Pai, S [iCAD Inc., Los Gatos, CA (United States)

    2015-06-15

    Purpose: The objective is to improve the efficiency and efficacy of Xoft™ Axxent™ electronic brachytherapy (EBT) calibration of the source & surface applicator using AAPM TG-61 formalism. Methods: Current method of Xoft EBT source calibration involves determination of absolute dose rate of the source in each of the four conical surface applicators using in-air chamber measurements & TG61 formalism. We propose a simplified TG-61 calibration methodology involving initial characterization of surface cone applicators. This is accomplished by calibrating dose rates for all 4 surface applicator sets (for 10 sources) which establishes the “applicator output ratios” with respect to the selected reference applicator (20 mm applicator). After the initial time, Xoft™ Axxent™ source TG61 Calibration is carried out only in the reference applicator. Using the established applicator output ratios, dose rates for other applicators will be calculated. Results: 200 sources & 8 surface applicator sets were calibrated cumulatively using a Standard Imaging A20 ion-chamber in accordance with manufacturer-recommended protocols. Dose rates of 10, 20, 35 & 50mm applicators were normalized to the reference (20mm) applicator. The data in Figure 1 indicates that the normalized dose rate variation for each applicator for all 200 sources is better than ±3%. The average output ratios are 1.11, 1.02 and 0.49 for the 10 mm,35 mm and 50 mm applicators, respectively, which are in good agreement with the manufacturer’s published output ratios of 1.13, 1.02 and 0.49. Conclusion: Our measurements successfully demonstrate the accuracy of a new calibration method using a single surface applicator for Xoft EBT sources and deriving the dose rates of other applicators. The accuracy of the calibration is improved as this method minimizes the source position variation inside the applicator during individual source calibrations. The new method significantly reduces the calibration time to less

  19. Fat Necrosis After Partial-Breast Irradiation With Brachytherapy or Electron Irradiation Versus Standard Whole-Breast Radiotherapy-4-Year Results of a Randomized Trial

    International Nuclear Information System (INIS)

    Loevey, Katalin; Fodor, Janos; Major, Tibor; Szabo, Eva; Orosz, Zsolt; Sulyok, Zoltan; Janvary, Levente; Froehlich, Georgina; Kasler, Miklos; Polgar, Csaba

    2007-01-01

    Purpose: To examine the incidence and clinical relevance of fat necrosis after accelerated partial-breast irradiation (PBI) using interstitial high-dose-rate brachytherapy (HDR-BT) in comparison with partial-breast electron irradiation (ELE) and whole-breast irradiation (WBI). Methods and Materials: Between 1998 and 2004, 258 early-stage breast cancer patients were randomized to receive 50 Gy WBI (n = 130) or PBI (n = 128). The latter consisted of either 7 x 5.2 Gy HDR-BT (n = 88) or 50 Gy ELE (n = 40). The incidence of fat necrosis, its impact on cosmetic outcome, accompanying radiologic features, and clinical symptoms were evaluated. Results: The 4-year actuarial rate of fat necrosis was 31.1% for all patients, and 31.9%, 36.5%, and 17.7% after WBI, HDR-BT and ELE, respectively (p WBI/HDR-BT = 0.26; p WBI/ELE = 0.11; p ELE/HDR-BT = 0.025). The respective rate of asymptomatic fat necrosis was 20.2%, 25.3%, and 10% of patients. The incidence of symptomatic fat necrosis was not significantly different after WBI (8.5%), HDR-BT (11.4%), and ELE (7.5%). Symptomatic fat necrosis was significantly associated with a worse cosmetic outcome, whereas asymptomatic fat necrosis was not. Fat necrosis was detectable with mammography and/or ultrasound in each case. Additional imaging examinations were required in 21% of cases and aspiration cytology in 42%. Conclusions: Asymptomatic fat necrosis is a common adverse event of breast-conserving therapy, having no significant clinical relevance in the majority of the cases. The incidence of both symptomatic and asymptomatic fat necrosis is similar after conventional WBI and accelerated partial-breast HDR-BT

  20. SU-D-210-07: The Dependence On Acoustic Velocity of Medium On the Needle Template and Electronic Grid Alignment in Ultrasound QA for Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kapoor, P; Kapoor, R; Curran, B [Virginia Commonwealth University, Richmond, VA (United States); HH McGuire VA Hospital, Richmond, VA (United States)

    2015-06-15

    Purpose: To analyze the impact on acoustic velocity (AV) of two different media (water and milk) using the needle template/electronic grid alignment test. Water, easily available, makes a good material to test the alignment of the template and grid although water’s AV (1498 m/s at 25°C) is significantly different from tissue (1540 m/s). Milk, with an AV much closer (1548 m/s) to prostate tissue, may be a good substitute for water in ultrasound quality assurance testing. Methods: Tests were performed using a Hitachi ultrasound unit with a mechanical arrangement designed to position needles parallel to the transducer. In this work, two materials – distilled water and homogenized whole milk (AVs of 1498 and 1548 m/s at 25°C) were used in a phantom to test ultrasound needle/grid alignment. The images were obtained with both materials and analyzed for their placement accuracy. Results: The needle template/electronic grid alignment tests showed displacement errors between measured and calculated values. The measurements showed displacements of 2.3mm (water) and 0.4mm (milk), and 1.6mm (water) and 0.3mm (milk) at depths of 7cm and 5cm respectively from true needle positions. The calculated results showed a displacement of 2.36 mm (water); 0.435mm (milk), and 1.66mm (water) and 0.31mm (milk) at a depth of 7cm and 5cm respectively. The displacements in the X and Y directions were also calculated. At depths of 7cm and 5cm, the (ΔX,ΔY) displacements in water were (0.829mm, 2.21mm) and (0.273mm, 1.634mm) and for milk were (0.15mm, 0.44mm) and (0.05mm, 0.302mm) respectively. Conclusion: The measured and calculated values were in good agreement for all tests. They show that milk provides superior results when performing needle template and electronic grid alignment tests for ultrasound units used in prostate brachytherapy.

  1. A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model

    International Nuclear Information System (INIS)

    Hiatt, Jessica R.; Davis, Stephen D.; Rivard, Mark J.

    2015-01-01

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft, Inc., was characterized by Rivard et al. in 2006. Since then, the source design was modified to include a new insert at the source tip. Current study objectives were to establish an accurate source model for simulation purposes, dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and determine dose differences between the original simulation model and the current model S700 source design. Methods: Design information from measurements of dissected model S700 sources and from vendor-supplied CAD drawings was used to aid establishment of an updated Monte Carlo source model, which included the complex-shaped plastic source-centering insert intended to promote water flow for cooling the source anode. These data were used to create a model for subsequent radiation transport simulations in a water phantom. Compared to the 2006 simulation geometry, the influence of volume averaging close to the source was substantially reduced. A track-length estimator was used to evaluate collision kerma as a function of radial distance and polar angle for determination of TG-43 dosimetry parameters. Results for the 50 kV source were determined every 0.1 cm from 0.3 to 15 cm and every 1° from 0° to 180°. Photon spectra in water with 0.1 keV resolution were also obtained from 0.5 to 15 cm and polar angles from 0° to 165°. Simulations were run for 10 10 histories, resulting in statistical uncertainties on the transverse plane of 0.04% at r = 1 cm and 0.06% at r = 5 cm. Results: The dose-rate distribution ratio for the model S700 source as compared to the 2006 model exceeded unity by more than 5% for roughly one quarter of the solid angle surrounding the source, i.e., θ ≥ 120°. The radial dose function diminished in a similar manner as for an 125 I seed, with values of 1.434, 0.636, 0.283, and 0.0975 at 0.5, 2, 5, and 10 cm, respectively. The radial dose function

  2. A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model

    Energy Technology Data Exchange (ETDEWEB)

    Hiatt, Jessica R. [Department of Radiation Oncology, Rhode Island Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island 02903 (United States); Davis, Stephen D. [Department of Medical Physics, McGill University Health Centre, Montreal, Quebec H3G 1A4 (Canada); Rivard, Mark J., E-mail: mark.j.rivard@gmail.com [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2015-06-15

    Purpose: The model S700 Axxent electronic brachytherapy source by Xoft, Inc., was characterized by Rivard et al. in 2006. Since then, the source design was modified to include a new insert at the source tip. Current study objectives were to establish an accurate source model for simulation purposes, dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and determine dose differences between the original simulation model and the current model S700 source design. Methods: Design information from measurements of dissected model S700 sources and from vendor-supplied CAD drawings was used to aid establishment of an updated Monte Carlo source model, which included the complex-shaped plastic source-centering insert intended to promote water flow for cooling the source anode. These data were used to create a model for subsequent radiation transport simulations in a water phantom. Compared to the 2006 simulation geometry, the influence of volume averaging close to the source was substantially reduced. A track-length estimator was used to evaluate collision kerma as a function of radial distance and polar angle for determination of TG-43 dosimetry parameters. Results for the 50 kV source were determined every 0.1 cm from 0.3 to 15 cm and every 1° from 0° to 180°. Photon spectra in water with 0.1 keV resolution were also obtained from 0.5 to 15 cm and polar angles from 0° to 165°. Simulations were run for 10{sup 10} histories, resulting in statistical uncertainties on the transverse plane of 0.04% at r = 1 cm and 0.06% at r = 5 cm. Results: The dose-rate distribution ratio for the model S700 source as compared to the 2006 model exceeded unity by more than 5% for roughly one quarter of the solid angle surrounding the source, i.e., θ ≥ 120°. The radial dose function diminished in a similar manner as for an {sup 125}I seed, with values of 1.434, 0.636, 0.283, and 0.0975 at 0.5, 2, 5, and 10 cm, respectively. The radial dose

  3. A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model.

    Science.gov (United States)

    Hiatt, Jessica R; Davis, Stephen D; Rivard, Mark J

    2015-06-01

    The model S700 Axxent electronic brachytherapy source by Xoft, Inc., was characterized by Rivard et al. in 2006. Since then, the source design was modified to include a new insert at the source tip. Current study objectives were to establish an accurate source model for simulation purposes, dosimetrically characterize the new source and obtain its TG-43 brachytherapy dosimetry parameters, and determine dose differences between the original simulation model and the current model S700 source design. Design information from measurements of dissected model S700 sources and from vendor-supplied CAD drawings was used to aid establishment of an updated Monte Carlo source model, which included the complex-shaped plastic source-centering insert intended to promote water flow for cooling the source anode. These data were used to create a model for subsequent radiation transport simulations in a water phantom. Compared to the 2006 simulation geometry, the influence of volume averaging close to the source was substantially reduced. A track-length estimator was used to evaluate collision kerma as a function of radial distance and polar angle for determination of TG-43 dosimetry parameters. Results for the 50 kV source were determined every 0.1 cm from 0.3 to 15 cm and every 1° from 0° to 180°. Photon spectra in water with 0.1 keV resolution were also obtained from 0.5 to 15 cm and polar angles from 0° to 165°. Simulations were run for 10(10) histories, resulting in statistical uncertainties on the transverse plane of 0.04% at r = 1 cm and 0.06% at r = 5 cm. The dose-rate distribution ratio for the model S700 source as compared to the 2006 model exceeded unity by more than 5% for roughly one quarter of the solid angle surrounding the source, i.e., θ ≥ 120°. The radial dose function diminished in a similar manner as for an (125)I seed, with values of 1.434, 0.636, 0.283, and 0.0975 at 0.5, 2, 5, and 10 cm, respectively. The radial dose function ratio between the current

  4. Radiation protection in brachytherapy

    International Nuclear Information System (INIS)

    Benitez, Manuel

    1996-02-01

    It covers technical procedures in medical applications for cancer treatment. Radiation protection principles in brachytherapy. Medical uses in therapy for Sr-90, Cs-137, Co-60, Ra-226, Ir-192, Au-198, Bi-214, Pb-214. (The author)

  5. Radioactive sources in brachytherapy:

    OpenAIRE

    Burger, Janez

    2003-01-01

    Background. In modern brachytherapy, a greast step forward was made in the 1960s in France with the introduction of new radioactive isotopes and new techniques. These innovations spread rapidly across Europe, though no single dosimetry standard had been set by then. In the new millennium, the advances in brachytherapy are further stimulated by the introduction of 3-D imaging techniques and the latest after loading irradiation equipment that use point sources. The international organiyation IC...

  6. SU-G-201-10: Experimental Determination of Modified TG-43 Dosimetry Parameters for the Xoft Axxent® Electronic Brachytherapy Source

    Energy Technology Data Exchange (ETDEWEB)

    Simiele, S; Palmer, B; DeWerd, L [Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI (United States)

    2016-06-15

    Purpose: The establishment of an air kerma rate standard at NIST for the Xoft Axxent{sup ®} electronic brachytherapy source (Axxent{sup ®} source) motivated the establishment of a modified TG-43 dosimetry formalism. This work measures the modified dosimetry parameters for the Axxent{sup ®} source in the absence of a treatment applicator for implementation in Xoft’s treatment planning system. Methods: The dose-rate conversion coefficient (DRCC), radial dose function (RDF) values, and polar anisotropy (PA) were measured using TLD-100 microcubes with NIST-calibrated sources. The DRCC and RDF measurements were performed in liquid water using an annulus of Virtual Water™ designed to align the TLDs at the height of the anode at fixed radii from the source. The PA was measured at several distances from the source in a PMMA phantom. MCNP-determined absorbed dose energy dependence correction factors were used to convert from dose to TLD to dose to liquid water for the DRCC, RDF, and PA measurements. The intrinsic energy dependence correction factor from the work of Pike was used. The AKR was determined using a NIST-calibrated HDR1000 Plus well-type ionization chamber. Results: The DRCC was determined to be 8.6 (cGy/hr)/(µGy/min). The radial dose values were determined to be 1.00 (1cm), 0.60 (2cm), 0.42 (3cm), and 0.32 (4cm), with agreement ranging from (5.7% to 10.9%) from the work of Hiatt et al. 2015 and agreement from (2.8% to 6.8%) with internal MCNP simulations. Conclusion: This work presents a complete dataset of modified TG-43 dosimetry parameters for the Axxent{sup ®} source in the absence of an applicator. Prior to this study a DRCC had not been measured for the Axxent{sup ®} source. This data will be used for calculating dose distributions for patients receiving treatment with the Axxent{sup ®} source in Xoft’s breast balloon and vaginal applicators, and for intraoperative radiotherapy. Sources and partial funding for this work were provided by Xoft

  7. SU-G-201-10: Experimental Determination of Modified TG-43 Dosimetry Parameters for the Xoft Axxent® Electronic Brachytherapy Source

    International Nuclear Information System (INIS)

    Simiele, S; Palmer, B; DeWerd, L

    2016-01-01

    Purpose: The establishment of an air kerma rate standard at NIST for the Xoft Axxent"® electronic brachytherapy source (Axxent"® source) motivated the establishment of a modified TG-43 dosimetry formalism. This work measures the modified dosimetry parameters for the Axxent"® source in the absence of a treatment applicator for implementation in Xoft’s treatment planning system. Methods: The dose-rate conversion coefficient (DRCC), radial dose function (RDF) values, and polar anisotropy (PA) were measured using TLD-100 microcubes with NIST-calibrated sources. The DRCC and RDF measurements were performed in liquid water using an annulus of Virtual Water™ designed to align the TLDs at the height of the anode at fixed radii from the source. The PA was measured at several distances from the source in a PMMA phantom. MCNP-determined absorbed dose energy dependence correction factors were used to convert from dose to TLD to dose to liquid water for the DRCC, RDF, and PA measurements. The intrinsic energy dependence correction factor from the work of Pike was used. The AKR was determined using a NIST-calibrated HDR1000 Plus well-type ionization chamber. Results: The DRCC was determined to be 8.6 (cGy/hr)/(µGy/min). The radial dose values were determined to be 1.00 (1cm), 0.60 (2cm), 0.42 (3cm), and 0.32 (4cm), with agreement ranging from (5.7% to 10.9%) from the work of Hiatt et al. 2015 and agreement from (2.8% to 6.8%) with internal MCNP simulations. Conclusion: This work presents a complete dataset of modified TG-43 dosimetry parameters for the Axxent"® source in the absence of an applicator. Prior to this study a DRCC had not been measured for the Axxent"® source. This data will be used for calculating dose distributions for patients receiving treatment with the Axxent"® source in Xoft’s breast balloon and vaginal applicators, and for intraoperative radiotherapy. Sources and partial funding for this work were provided by Xoft Inc. (a subsidiary of i

  8. Image Guided Cervical Brachytherapy: 2014 Survey of the American Brachytherapy Society

    Energy Technology Data Exchange (ETDEWEB)

    Grover, Surbhi, E-mail: Surbhi.grover@uphs.upenn.edu [Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Harkenrider, Matthew M. [Department of Radiation Oncology, Stritch School of Medicine, Loyola University Chicago, Chicago, Illinois (United States); Cho, Linda P. [Department of Radiation Oncology, Brigham & Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Erickson, Beth [Department Radiation Oncology, Froedtert Hospital and Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Small, Christina [Department of Public Health Sciences, Stritch School of Medicine, Loyola University Chicago, Chicago, Illinois (United States); Small, William [Department of Radiation Oncology, Stritch School of Medicine, Loyola University Chicago, Chicago, Illinois (United States); Viswanathan, Akila N. [Department of Radiation Oncology, Brigham & Women' s Hospital/Dana-Farber Cancer Institute, Boston, Massachusetts (United States)

    2016-03-01

    Purpose: To provide an update of the 2007 American brachytherapy survey on image-based brachytherapy, which showed that in the setting of treatment planning for gynecologic brachytherapy, although computed tomography (CT) was often used for treatment planning, most brachytherapists used point A for dose specification. Methods and Materials: A 45-question electronic survey on cervical cancer brachytherapy practice patterns was sent to all American Brachytherapy Society members and additional radiation oncologists and physicists based in the United States between January and September 2014. Responses from the 2007 survey and the present survey were compared using the χ{sup 2} test. Results: There were 370 respondents. Of those, only respondents, not in training, who treat more than 1 cervical cancer patient per year and practice in the United States, were included in the analysis (219). For dose specification to the target (cervix and tumor), 95% always use CT, and 34% always use MRI. However, 46% use point A only for dose specification to the target. There was a lot of variation in parameters used for dose evaluation of target volume and normal tissues. Compared with the 2007 survey, use of MRI has increased from 2% to 34% (P<.0001) for dose specification to the target. Use of volume-based dose delineation to the target has increased from 14% to 52% (P<.0001). Conclusion: Although use of image-based brachytherapy has increased in the United States since the 2007 survey, there is room for further growth, particularly with the use of MRI. This increase may be in part due to educational initiatives. However, there is still significant heterogeneity in brachytherapy practice in the United States, and future efforts should be geared toward standardizing treatment.

  9. Motivations for Intravaginal Product Use among a Cohort of Women in Los Angeles.

    Directory of Open Access Journals (Sweden)

    Joelle M Brown

    Full Text Available Intravaginal practices-including behaviors such as intravaginal cleansing and insertion of products-have been linked to a number of adverse reproductive health outcomes, including increased risk for bacterial vaginosis, sexually transmitted infections, and HIV. Currently, little is known about the motivations for intravaginal practices among women in the United States. The objective of this study was to identify and describe motivations for intravaginal washing and intravaginal insertion of products among women of differing ages and racial/ethnic groups.Between 2008 and 2010, we enrolled a convenience sample of sexually active women aged 18-65 years living in Los Angeles recruited through community education and outreach activities in HIV/AIDS service organizations, women's health clinics, community-based organizations, and HIV testing sites. At the enrollment visit, women completed a self-administered, computer-assisted questionnaire covering demographics, sexual behaviors, intravaginal practices, and motivations for intravaginal practices over the past month and past year.We enrolled 141 women; 34% of participants were Caucasian, 40% African American, and 26% Latina. Peri-sexual intravaginal washing was common in all groups, whether to clean up after sex (70% or to prepare for sex (54%. African American women were more likely to report learning to wash intravaginally from their mothers compared to Latina or Caucasian women (70% vs. 49%, P = 0.04. Sixty-one percent of African American women reported using a douching device over the past year compared to 41% of Latina and 40% of Caucasian women (p = 0.02. Younger women were more likely to report that their male partners wanted them to wash intravaginally than older women (77% vs. 24%, P<0.01, and more likely to report the removal of odors as a motive than older women (65% vs. 40%, P = 0.04. The most commonly used intravaginal products included sexual lubricants, petroleum jelly, body lotions

  10. Brachytherapy of endometrial cancers

    International Nuclear Information System (INIS)

    Peiffert, D.; Hoffstetter, S.; Charra-Brunaud, C.

    2003-01-01

    Endometrial adenocarcinomas rank third as tumoral sites en France. The tumors are confined to the uterus in 80% of the cases. Brachytherapy has a large place in the therapeutic strategy. The gold standard treatment remains extra-fascial hysterectomy with bilateral annexiectomy and bilateral internal iliac lymph node dissection. However, after surgery alone, the rate of locoregional relapses reaches 4-20%, which is reduced to 0-5% after postoperative brachytherapy of the vaginal cuff. This postoperative brachytherapy is delivered as outpatients treatment, by 3 or 4 fractions, at high dose rate. The utero-vaginal preoperative brachytherapy remains well adapted to the tumors which involve the uterine cervix. Patients presenting a localized tumor but not operable for general reasons (< 10%) can be treated with success by exclusive irradiation, which associates a pelvic irradiation followed by an utero-vaginal brachytherapy. A high local control of about 80-90% is obtained, a little lower than surgery, with a higher risk of late complications. Last but not least, local relapses in the vaginal cuff, or in the perimeatic area, can be treated by interstitial salvage brachytherapy, associated if possible with external beam irradiation. The local control is reached in half of the patients, but metastatic dissemination is frequent. We conclude that brachytherapy has a major role in the treatment of endometrial adenocarcinomas, in combination with surgery, or with external beam irradiation for not operable patients or in case of local relapses. It should use new technologies now available including computerized after-loaders and 3D dose calculation. (authors)

  11. SU-F-T-02: Estimation of Radiobiological Doses (BED and EQD2) of Single Fraction Electronic Brachytherapy That Equivalent to I-125 Eye Plaque: By Using Linear-Quadratic and Universal Survival Curve Models

    International Nuclear Information System (INIS)

    Kim, Y; Waldron, T; Pennington, E

    2016-01-01

    Purpose: To test the radiobiological impact of hypofractionated choroidal melanoma brachytherapy, we calculated single fraction equivalent doses (SFED) of the tumor that equivalent to 85 Gy of I125-BT for 20 patients. Corresponding organs-at-risks (OARs) doses were estimated. Methods: Twenty patients treated with I125-BT were retrospectively examined. The tumor SFED values were calculated from tumor BED using a conventional linear-quadratic (L-Q) model and an universal survival curve (USC). The opposite retina (α/β = 2.58), macula (2.58), optic disc (1.75), and lens (1.2) were examined. The % doses of OARs over tumor doses were assumed to be the same as for a single fraction delivery. The OAR SFED values were converted into BED and equivalent dose in 2 Gy fraction (EQD2) by using both L-Q and USC models, then compared to I125-BT. Results: The USC-based BED and EQD2 doses of the macula, optic disc, and the lens were on average 118 ± 46% (p 14 Gy). Conclusion: The estimated single fraction doses were feasible to be delivered within 1 hour using a high dose rate source such as electronic brachytherapy (eBT). However, the estimated OAR doses using eBT were 112 ∼ 118% higher than when using the I125-BT technique. Continued exploration of alternative dose rate or fractionation schedules should be followed.

  12. Compartmental transport model of microbicide delivery by an intravaginal ring

    Science.gov (United States)

    Geonnotti, Anthony R.; Katz, David F.

    2010-01-01

    Topical antimicrobials, or microbicides, are being developed to prevent HIV transmission through local, mucosal delivery of antiviral compounds. While hydrogel vehicles deliver the majority of current microbicide products, intravaginal rings (IVRs) are an alternative microbicide modality in preclinical development. IVRs provide a long-term dosing alternative to hydrogel use, and might provide improved user adherence. IVR efficacy requires sustained delivery of antiviral compounds to the entire vaginal compartment. A two-dimensional, compartmental vaginal drug transport model was created to evaluate the delivery of drugs from an intravaginal ring. The model utilized MRI-derived ring geometry and location, experimentally defined ring fluxes and vaginal fluid velocities, and biophysically relevant transport theory. Model outputs indicated the presence of potentially inhibitory concentrations of antiviral compounds along the entire vaginal canal within 24 hours following IVR insertion. Distributions of inhibitory concentrations of antiviral compounds were substantially influenced by vaginal fluid flow and production, while showing little change due to changes in diffusion coefficients or ring fluxes. Additionally, model results were predictive of in vivo concentrations obtained in clinical trials. Overall, this analysis initiates a mechanistic computational framework, heretofore missing, to understand and evaluate the potential of IVRs for effective delivery of antiviral compounds. PMID:20222027

  13. Dosimetry in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing 32 P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  14. Afterloading techniques in brachytherapy

    International Nuclear Information System (INIS)

    Kirsch, M.; Orban, R.; Lorenz, B.

    1981-01-01

    The advantages of applying modern afterloading methods in brachytherapie of malignant diseases are outlined. They include, among other things, a considerable reduction in radiation exposure to staff involved. Furthermore, the radiation protection requirements imposed by the licensing authority on the construction, equipment and operation of remote controlled afterloading installations with gamma sources of up to 4 TBq (108 Ci) have been compiled. (author)

  15. Brachytherapy for oral cancer

    International Nuclear Information System (INIS)

    Monzen, Yoshio; Ajimu, Akira; Morikawa, Minoru; Hayashi, Nobuyuki; Yoshida, Shintarou; Ashizawa, Kazuto; Hayashi, Kuniaki; Ikenaga, Kouji; Sakamoto, Ichirou.

    1988-01-01

    13 cases with oral cancer were treated using brachytherapy at the Department of Radiology, Nagasaki University Hospital from September 1985 to February 1988. Among 11 cases of tongue cancer, T1 and T2 cases were well controlled by radiation therapy using 226 Ra needles. Cancer of oral floor and buccal mucosa were controlled by the use of 192 Au grains. (author)

  16. [Brachytherapy of brainstem tumors].

    Science.gov (United States)

    Julow, Jenö; Viola, Arpád; Major, Tibor; Valálik, István; Sági, Sarolta; Mangel, László; Kovács, Rita Beáta; Repa, Imre; Bajzik, Gábor; Németh, György

    2004-01-20

    The optimal therapy of brain stem tumours of different histopathology determines the expected length of survival. Authors report 125Iodine interstitial irradiation of brain stem tumours with stereotactic brachytherapy. Two patients having brain stem tumours were suffering from glioma or from metastases of a carcinoma. In Case 1 the tumour volume was 1.98 cm3 at the time of planning interstitial irradiation. The control MRI examination performed at 42 months post-op showed a postirradiation cyst size of 5.73 cm3 indicating 65.5% shrinkage. In Case 2 the shrinkage was more apparent as the tumour volume measured on the control MRI at 8 months post-op was only 0.16 cm3 indicating 97.4% shrinkage of the 6.05 cm3 target volume at the time of brachytherapy with the metastasis practically disappearing. Quick access to histopathological results of the stereotactic intraoperative biopsy made it possible to carry out the 125Iodine stereotactic brachytherapy immediately after the biopsy, resulting in less inconvenience for patients of a second possible intervention. The control MRI scans show significant shrinkage of tumours in both patients. The procedure can be performed as a biopsy. The CT and image fusion guided 125Iodine stereotactic brachytherapy can be well planned dosimetrically and is surgically precise.

  17. National audit of a system for rectal contact brachytherapy

    Directory of Open Access Journals (Sweden)

    Laia Humbert-Vidan

    2017-01-01

    Full Text Available Background and purpose: Contact brachytherapy is used for the treatment of early rectal cancer. An overview of the current status of quality assurance of the rectal contact brachytherapy systems in the UK, based on a national audit, was undertaken in order to assist users in optimising their own practices. Material and methods: Four UK centres using the Papillon 50 contact brachytherapy system were audited. Measurements included beam quality, output and radiation field size and uniformity. Test frequencies and tolerances were reviewed and compared to both existing recommendations and published reviews on other kV and electronic brachytherapy systems. External validation of dosimetric measurements was provided by the National Physical Laboratory. Results: The maximum host/audit discrepancy in beam quality determination was 6.5%; this resulted in absorbed dose variations of 0.2%. The host/audit agreement in absorbed dose determination was within 2.2%. The median of the radiation field uniformity measurements was 2.7% and the host/audit agreement in field size was within 1 mm. Test tolerances and frequencies were within the national recommendations for kV units. Conclusions: The dosimetric characterisation of the Papillon 50 was validated by the audit measurements for all participating centres, thus providing reassurance that the implementation had been performed within the standards stated in previously published audit work and recommendations for kV and electronic brachytherapy units. However, optimised and standardised quality assurance testing could be achieved by reducing some methodological differences observed. Keywords: Contact brachytherapy, Electronic brachytherapy, Audit

  18. Control, communication and monitoring of intravaginal drug delivery in dairy cows.

    Science.gov (United States)

    Cross, Peter S; Künnemeyer, Rainer; Bunt, Craig R; Carnegie, Dale A; Rathbone, Michael J

    2004-09-10

    We present the design of an electronically controlled drug delivery system. The intravaginally located device is a low-invasive platform that can measure and react inside the cow vagina while providing external control and monitoring ability. The electronics manufactured from off the shelf components occupies 16 mL of a Theratron syringe. A microcontroller reads and logs sensor data and controls a gascell. The generated gas pressure propels the syringe piston and releases the formulation. A two way radio link allows communication between other devices or a base station. Proof of principle experiments confirm variable-rate, arbitrary profile drug delivery qualified by internal sensors. A total volume of 30 mL was dispensed over a 7-day-period with a volume error of +/- 1 mL or +/- 7% for larger volumes. Delivery was controlled or overridden via the wireless link, and proximity to other devices was detected and recorded. The results suggest that temperature and activity sensing or social grouping determined via proximity can be used to detect oestrus and trigger appropriate responses.

  19. A multinational population survey of intravaginal ejaculation latency time.

    Science.gov (United States)

    Waldinger, Marcel D; Quinn, Paul; Dilleen, Maria; Mundayat, Rajiv; Schweitzer, Dave H; Boolell, Mitradev

    2005-07-01

    Intravaginal ejaculation latency time (IELT), defined as the time between the start of vaginal intromission and the start of intravaginal ejaculation, is increasingly used in clinical trials to assess the amount of selective serotonin reuptake inhibitor-induced ejaculation delay in men with premature ejaculation. Prospectively, stopwatch assessment of IELTs has superior accuracy compared with retrospective questionnaire and spontaneous reported latency. However, the IELT distribution in the general male population has not been previously assessed. To determine the stopwatch assessed-IELT distribution in large random male cohorts of different countries. A total of 500 couples were recruited from five countries: the Netherlands, United Kingdom, Spain, Turkey, and the United States. Enrolled men were aged 18 years or older, had a stable heterosexual relationship for at least 6 months, with regular sexual intercourse. The surveyed population were not included or excluded by their ejaculatory status and comorbidities. This survey was performed on a "normal" general population. Sexual events and stopwatch-timed IELTs during a 4-week period were recorded, as well as circumcision status and condom use. The IELT, circumcision status, and condom use. The distribution of the IELT in all the five countries was positively skewed, with a median IELT of 5.4 minutes (range, 0.55-44.1 minutes). The median IELT decreased significantly with age, from 6.5 minutes in the 18-30 years group, to 4.3 minutes in the group older than 51 years (PIELT varied between countries, with the median value for Turkey being the lowest, i.e., 3.7 minutes (0.9-30.4 minutes), which was significantly different from each of the other countries. Comparison of circumcised (N=98) and not-circumcised (N=261) men in countries excluding Turkey resulted in median IELT values of 6.7 minutes (0.7-44.1 minutes) in circumcised compared with 6.0 minutes (0.5-37.4 minutes) in not-circumcised men (not significant). The

  20. Glass microspheres for brachytherapy

    International Nuclear Information System (INIS)

    Prado, Miguel O.; Prastalo, Simon; Blaumann, Herman; Longhino, Juan M.; Repetto Llamazares, A.H.V.

    2007-01-01

    We developed the capacity to produce glass microspheres containing in their structure one or more radioactive isotopes useful for brachytherapy. We studied the various facts related with their production: (Rare earth) alumino silicate glass making, glass characterization, microspheres production, nuclear activation through (n,γ) nuclear reactions, mechanical characterization before and after irradiation. Corrosion tests in simulated human plasma and mechanical properties characterization were done before and after irradiation. (author) [es

  1. Computed tomography in brachytherapy

    International Nuclear Information System (INIS)

    Mansfield, C.M.; Lee, K.R.; Dwyer, S.; Zellmer, D.; Cook, P.

    1983-01-01

    CT scanning adds to the ability to evaluate brachytherapy techniques. It provides an additional method in the assessment of patients who are candidates for or who are being treated by brachytherapy. The CT scan can give information regarding the position of the sources and their relation to the tumor and normal structures with greater ease than do orthogonal views. This makes it possible to accurately calculate areas of high or low dose. Potential areas of overdose can be recognized, thereby decreasing the chances of postbrachytherapy complications. CT scanning can be used at various levels of complexity in dosimetry evaluation. Adequate brachytherapy dosimetry information is obtainable from CT slices through one or more levels of the implanted volume. In some instances it is possible to obtain additional information by reconstructing the scans in other planes, e.g., coronal or sagittal. Three-dimensional viewing of the implant is desirable, but it should be pointed out that this approach is time-consuming and beyond the capabilities of most institutions at present. It will be necessary to continue work on three-dimensional treatment planning to make it readily available

  2. Intravaginal practices, bacterial vaginosis, and HIV infection in women: individual participant data meta-analysis.

    Directory of Open Access Journals (Sweden)

    Nicola Low

    2011-02-01

    Full Text Available Identifying modifiable factors that increase women's vulnerability to HIV is a critical step in developing effective female-initiated prevention interventions. The primary objective of this study was to pool individual participant data from prospective longitudinal studies to investigate the association between intravaginal practices and acquisition of HIV infection among women in sub-Saharan Africa. Secondary objectives were to investigate associations between intravaginal practices and disrupted vaginal flora; and between disrupted vaginal flora and HIV acquisition.We conducted a meta-analysis of individual participant data from 13 prospective cohort studies involving 14,874 women, of whom 791 acquired HIV infection during 21,218 woman years of follow-up. Data were pooled using random-effects meta-analysis. The level of between-study heterogeneity was low in all analyses (I(2 values 0.0%-16.1%. Intravaginal use of cloth or paper (pooled adjusted hazard ratio [aHR] 1.47, 95% confidence interval [CI] 1.18-1.83, insertion of products to dry or tighten the vagina (aHR 1.31, 95% CI 1.00-1.71, and intravaginal cleaning with soap (aHR 1.24, 95% CI 1.01-1.53 remained associated with HIV acquisition after controlling for age, marital status, and number of sex partners in the past 3 months. Intravaginal cleaning with soap was also associated with the development of intermediate vaginal flora and bacterial vaginosis in women with normal vaginal flora at baseline (pooled adjusted odds ratio [OR] 1.24, 95% CI 1.04-1.47. Use of cloth or paper was not associated with the development of disrupted vaginal flora. Intermediate vaginal flora and bacterial vaginosis were each associated with HIV acquisition in multivariable models when measured at baseline (aHR 1.54 and 1.69, p<0.001 or at the visit before the estimated date of HIV infection (aHR 1.41 and 1.53, p<0.001, respectively.This study provides evidence to suggest that some intravaginal practices increase

  3. Posterior intravaginal slingplasty with preservation of the uterus: a modified surgical technique in a young myelomeningocele patient

    NARCIS (Netherlands)

    Verguts, Jasper; Roovers, Jan-Paul; de Ridder, Dirk; Coremans, Georges; Deprest, Jan

    2007-01-01

    We report a case of uterine prolapse in a young woman, treated by posterior intravaginal slingplasty with preservation of the uterus as a feasible and safe surgical procedure. Posterior intravaginal slingplasty is commonly used to correct vaginal vault prolapse, but may be a valuable alternative to

  4. Intravaginal insertion in KwaZulu Natal: sexual practices and preferences in the context of microbicide gel use

    NARCIS (Netherlands)

    Gafos, M.; Mzimela, M.; Sukazi, S.; Pool, R.; Montgomery, C.; Elford, J.

    2010-01-01

    Intravaginal insertion is often associated with the concept of ‘dry’ sex. All HIV-prevention microbicides tested to date have been vaginally applied lubricant-based gels. In this paper, we examine whether the use of intravaginal insertions could be in conflict with the introduction of vaginal

  5. Intra coronary brachytherapy

    International Nuclear Information System (INIS)

    Ghofourian, H.; Ghahremani, A.; Oliaie, A.; Taghizadeh Asl, M.

    2002-01-01

    Despite the initial promise of vasculopathy intervention restenosis- a consequence of the (normal) would healing process-has emerged as a major problem. Angiographic restenosis has been reported in 40-60% of patients after successful P TCA. The basic mechanism of restenosis, (acute recoil, negative remodeling and neo intimal hyperplasia), are only partially counteracted by endovascular prosthetic devices (s tents). The rate of in-s tent restenosis, which is primarily caused by neo intimal hyperplasia due to the (micro) trauma of the arterial wall by the s tent struts, has been reduced to 18-32%. Ionizing (beta or gamma) radiations has been established as a potent treatment for malignant disorders. In recent years, there has also been increasing interest among clinicians in the management of benign lesions with radiation. Over the past several years, there has been a growing body of evidence that endovascular brachytherapy has a major impact on the biology of the restenosis. It must be underlined that understanding the biology and pathophysiology of restenosis and assessing various treatment options should preferably be a team effort, with the three g races b eing interventional cardiologist, nuclear oncologist, and industrial partners. The vast amount of data in over 20000 patients from a wide range of randomized controlled trials, has shown that brachytherapy is the only effective treatment for in-s tent restenosis. We are learning more and more about how to improve brachytherapy. While the new coated s tents that we heard about today is fascinating and extremely promising, brachytherapy still has a very important place in difficult patients, such as those with total occlusions, osti al lesions, left main lesions, multivessel disease and diabetes. Regarding to above mentioned tips, we (a research team work, in the Nuclear Research Center Of the Atomic Energy Organization Of Iran), focused on synthesis and preparation of radioactive materials for use in I c-B T. We

  6. Oncentra brachytherapy planning system.

    Science.gov (United States)

    Yang, Jack

    2018-03-27

    In modern cancer management, treatment planning has progressed as a contemporary tool with all the advances in computing power in recent years. One of the advanced planning tools uses 3-dimensional (3D) data sets for accurate dose distributions in patient prescription. Among these planning processes, brachytherapy has been a very important part of a successful cancer management program, offering clinical benefits with specific or combined treatments with external beam therapy. In this chapter, we mainly discussed the Elekta Oncentra planning system, which is the main treatment planning tool for high-dose rate (HDR) modality in our facility and in many other facilities in the United States. HDR is a technically advanced form of brachytherapy; a high-intensity radiation source (3.6 mm in length) is delivered with step motor in submillimeter precision under computer guidance directly into the tumor areas while minimizing injury to surrounding normal healthy tissue. Oncentra planning is the key component to generate a deliverable brachytherapy procedure, which is executed on the microSelectron V3 remote afterloader treatment system. Creating a highly conformal plan can be a time-consuming task. The development of Oncentra software (version 4.5.3) offers a variety of useful tools that facilitate many of the clinical challenging tasks for planning, such as contouring and image reconstruction, as well as rapid planning calculations with dose and dose volume histogram analysis. Oncentra Brachy module creates workflow and optimizes the planning accuracy for wide varieties of clinical HDR treatments, such as skin, gynecologic (GYN), breast, prostate, and many other applications. The treatment file can also be transferred to the afterloader control station for speedy delivery. The design concept, calculation algorithms, and optimization modules presented some key characteristics to plan and treat the patients effectively and accurately. The dose distribution and accuracy of

  7. Development of brachytherapy medium doserate

    International Nuclear Information System (INIS)

    Atang Susila; Ari Satmoko; Ahmad Rifai; Kristiyanti

    2010-01-01

    Brachytherapy has proven to be an effective treatment for different types of cancers and it become a common treatment modality in most radiotherapy clinics. PRPN has had experience in development of Low Dose Rate Brachytherapy for cervix cancer treatment. However the treatment process using LDR device needs 5 hours in time that the patient feel uncomfort. Therefore PRPN develops Medium Dose Rate Brachytherapy with radiation activity not more than 5 Currie. The project is divided into two stages. Purchasing of TPS software and TDS design are held in 2010, and the construction will be in 2011. (author)

  8. SU-F-T-02: Estimation of Radiobiological Doses (BED and EQD2) of Single Fraction Electronic Brachytherapy That Equivalent to I-125 Eye Plaque: By Using Linear-Quadratic and Universal Survival Curve Models

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y; Waldron, T; Pennington, E [University Of Iowa, College of Medicine, Iowa City, IA (United States)

    2016-06-15

    Purpose: To test the radiobiological impact of hypofractionated choroidal melanoma brachytherapy, we calculated single fraction equivalent doses (SFED) of the tumor that equivalent to 85 Gy of I125-BT for 20 patients. Corresponding organs-at-risks (OARs) doses were estimated. Methods: Twenty patients treated with I125-BT were retrospectively examined. The tumor SFED values were calculated from tumor BED using a conventional linear-quadratic (L-Q) model and an universal survival curve (USC). The opposite retina (α/β = 2.58), macula (2.58), optic disc (1.75), and lens (1.2) were examined. The % doses of OARs over tumor doses were assumed to be the same as for a single fraction delivery. The OAR SFED values were converted into BED and equivalent dose in 2 Gy fraction (EQD2) by using both L-Q and USC models, then compared to I125-BT. Results: The USC-based BED and EQD2 doses of the macula, optic disc, and the lens were on average 118 ± 46% (p < 0.0527), 126 ± 43% (p < 0.0354), and 112 ± 32% (p < 0.0265) higher than those of I125-BT, respectively. The BED and EQD2 doses of the opposite retina were 52 ± 9% lower than I125-BT. The tumor SFED values were 25.2 ± 3.3 Gy and 29.1 ± 2.5 Gy when using USC and LQ models which can be delivered within 1 hour. All BED and EQD2 values using L-Q model were significantly larger when compared to the USC model (p < 0.0274) due to its large single fraction size (> 14 Gy). Conclusion: The estimated single fraction doses were feasible to be delivered within 1 hour using a high dose rate source such as electronic brachytherapy (eBT). However, the estimated OAR doses using eBT were 112 ∼ 118% higher than when using the I125-BT technique. Continued exploration of alternative dose rate or fractionation schedules should be followed.

  9. A Rare Cause of Scrotal Mass in a Newborn: Antenatal Intravaginal Testicular Torsion

    Directory of Open Access Journals (Sweden)

    Ahmet Ali Tuncer

    2018-04-01

    Full Text Available Intravaginal testicular torsion is a very rare pathology in the neonatal period. However, it is the most common type of torsion in puberty. In this article, we present a male patient with testicular hyperemia and a mass in the testis. Ultrasonography revealed intravaginal testicular torsion and absence of testicular blood flow. This paper aims to draw attention to the importance of neonatal examination for the presence of testicular torsion which is a rare pathology in newborns with scrotal colour change or presence of an abnormal mass.

  10. Dosimetric Comparison of 3-Dimensional Planning Techniques Using an Intravaginal Multichannel Balloon Applicator for High-Dose-Rate Gynecologic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang-June, E-mail: spark@mednet.ucla.edu; Chung, Melody; Demanes, D. Jeffrey; Banerjee, Robyn; Steinberg, Michael; Kamrava, Mitchell

    2013-11-15

    Purpose: To study the dosimetric differences of various channel combinations of the Capri vaginal applicator. Methods and Materials: The Capri consists of a single central channel (R1), an inner array of 6 channels (R2), and an outer array of 6 channels (R3). Three-dimensional plans were simulated for 6 channel arrangements (R1, R2, R12, R13, R23, and R123). Treatment plans were optimized to the applicator surface or 5-mm depth while minimizing dose to organs at risk (OARs: bladder, rectum, sigmoid, and urethra). The clinical target volume (CTV) was defined as a 5-mm circumferential shell extending 4 cm in length around the applicator. Clinical target volume coverage (D{sub mean}, D{sub 90}, V{sub 100}, and V{sub 150}) and OAR doses (D{sub 0.1} {sub cm{sup 3}}, D{sub 1} {sub cm{sup 3}}, D{sub 2} {sub cm{sup 3}}, and D{sub mean}) were compared. A comparison between the Capri (R123) and a conventional single-channel applicator was also done. Statistical significance (P value <.05) was evaluated with a 2-tailed t test. Results: When prescribing to 5-mm depth, CTV coverage using all 13 channels (R123) versus a single channel (R1) was similar; however, when prescribing to the surface there were differences (P<.0001) in all CTV metrics except for the V{sub 150}. The R1 plans had higher doses to all OARs compared with R123 plans (P<.007). Doses to OARs were not significantly different between R23 and R123 plans (P=.05-.95), and CTV coverage differences were on the order of 1%. Capri R123 plans provided slightly lower CTV D{sub 90} and D{sub mean} but equivalent OAR doses with smaller standard deviations compared with conventional cylinder plans for both prescriptions. Conclusions: The Capri multichannel applicator provides equivalent target coverage at 5-mm depth, with significantly reduced dose to OARs relative to using a single channel. Optimal plans can be achieved using R12 (lowest V{sub 150}) or R123 or R23 (lowest OAR doses)

  11. [Developments in brachytherapy].

    Science.gov (United States)

    Ikeda, H

    1995-09-01

    Brachytherapy is one of the ideal methods of radiotherapy because of the concentration of a high dose on the target. Recent developments, including induction of afterloading method, utilization of small-sized high-activity sources such as Iridium-192, and induction of high technology and computerization, have made for shortening of irradiation time and source handling, which has led to easier management of the patient during treatment. Dose distribution at high dose rate (HDR) is at least as good as that of low dose rate (LDR), and selection of fractionation and treatment time assures even greater biological effects on hypoxic tumor cells than LDR. Experience with HDR brachytherapy in uterine cervix cancer using Cobalt-60 during the past 20 years in this country has gradually been evaluated in U.S. and Europe. The indications for HDR treatment have extended to esophagus, bronchus, bile duct, brain, intraoperative placement of source guide, and perineal region using templates, as well as the conventional use for uterus, tongue and so on.

  12. Brachytherapy in childhood rhabdomyosarcoma treatment

    International Nuclear Information System (INIS)

    Novaes, Paulo Eduardo Ribeiro dos Santos

    1995-01-01

    A retrospective study of 21 children with rhabdomyosarcoma treated by brachytherapy to the primary site of the tumor at the Radiotherapy Department of the A.C.Camargo Hospital between january/1980 to june/1993 was undertaken. The main objectives were to comprove the utility of brachytherapy in childhood rhabdomyosarcoma, to evaluate the local control and survival, in association with chemotherapy, to analyze the late effects of the treatment and to determinate the preferential technique to each clinical situation. All patients received brachytherapy to the tumor site. The radioactive isotopes employed were Gold 198 , Cesium 137 and Iridium 192 . The brachytherapy techniques depended on the tumor site, period of treatment, availability of the radioactive material and stage of the disease. Patients treated exclusively by brachytherapy received 40 Gy to 60 Gy. When brachytherapy was associated with external radiotherapy the dose ranged from 20 Gy to 40 Gy. Local control was achieved in 18 of 20 patients (90%). The global survival and local control survival rates were 61.9% (13/21 patients) and 72,2% (13/18 patients) respectively. (author)

  13. Proceedings of the Second Congress of Radiochemotherapy and Brachytherapy and the Fifth Meeting of Medical Physics

    International Nuclear Information System (INIS)

    Zunino, Silvia; Venencia, Daniel; Martinez, Monica; Garrigo, Edgardo

    2009-01-01

    The Marie Curie Foundation in the city of Cordoba in Argentina, has organized the Second Congress of radiochemotherapy and brachytherapy and the Fifth Meeting of Medical Physics in order to collaborate with the scientific growth of radiation oncology and medical physics. The main topics covered were: patient's radioprotection, brachytherapy with iodine, radiation protection regulatory issues in Argentina, risk analysis in radiotherapy, medical radiation therapy, EPID dosimetry (Electronic Portal Image Device), accidents in radiotherapy, among others. [es

  14. American brachytherapy society (ABS) guidelines for brachytherapy of esophageal cancer

    International Nuclear Information System (INIS)

    Nag, Subir; Gaspar, Laurie; Herskovic, Arnold; Mantravadi, Prasad; Speiser, Burton

    1996-01-01

    Introduction: There is wide variation in the indications, techniques, treatment regimens and dosimetry being used to treat cancer of the esophagus and no guidelines exist for optimal therapy. Methods: The Clinical Research Committee of the ABS met to formulate consensus guidelines for brachytherapy in esophageal cancer. Results: Good candidates for brachytherapy include patients with unifocal disease, with thoracic tumor 10 cm primary regional lymph adenopathy or tumor located in the gastro-esophageal junction or cervical esophagus. Contraindications include tracheo-esophageal fistula or stenosis that cannot be by-passed. The esophageal or nasogastric tube inserted should have a diameter of 6-10 mm whenever possible. If 5FU-based chemotherapy and 50 Gy external beam (EBRT) are used, it is suggested that the low dose rate brachytherapy (LDR) dose be 20 Gy at 0.4-1 Gy/hr, prescribed at 1 cm from the source. If high dose rate (HDR) is used, the dose recommended is 10 Gy in 2 weekly fractions of 5 Gy each, given after EBRT. Chemotherapy is not usually given concurrently with brachytherapy, and when it is, the brachytherapy dose is reduced. The length of esophagus treated by brachytherapy includes the post-EBRT involved area and a 1-2 cm margin proximally and distally. Supportive care, given during EBRT includes an antifungal agent (e.g., diflucan) and carafate. Gradual dilatation of the esophagus is required post-treatment for esophageal strictures. Conclusion: Guidelines were developed for brachytherapy in esophageal cancer. As more clinical data becomes available, these guidelines will be updated by the ABS

  15. Experiences with alanine dosimetry in afterloading brachytherapy

    International Nuclear Information System (INIS)

    Eberhardt, H.-J.; Gohs, U.

    1996-01-01

    At the present, the most commonly used dosimetry for radiotherapy applications are ionisation chambers and thermoluminescent dosimeters (TLD). However, there are some undesirable characteristics of these dosimetry systems, such as large detection volume (ionisation chamber) as well as fading of the radiation induced signal with time and destructive readout (TLG). The present study is an investigation into the use of the alanine/ESR dosimetry in fractionated afterloading brachytherapy during the whole radiotherapy course. There are some qualities which make alanine dosimetry attractive. These are the linear energy response, low fading under standard conditions, and the nondestructive readout. Thus the alanine dosimetry makes possible cumulative dose measurements during the radiotherapy course and an archival storage. By ionizing radiation (gamma, e, n, p, charged particles) free radicals (unpaired electrons) are produced in the amino acid alanine. The continuous wave electron spin resonance (ESR) spectroscopy is used to determine the number of free radicals, which is proportional to the absorbed dose and the alanine content of the dosimeter. The ESR measurements were made at room temperature using a Bruker EPR analyzer EMS-104. The dosimeters used in the test are alanine pellets (23.72 mg weight, 4.9 mm diameter, 1 mm height) as well as flexible alanine film dosimeters (thickness about 500 μm). The dosimeters consist of a blend of L-alpha-alanine and a binder. The alanine content of the pellets and the film dosimeters is about 88 % and 50 % by weight, respectively. The dosimeters for the calculation of the dose-effect-relationship were irradiated at the Physical-Technical Bundesanstalt in Braunschweig by a standard 60Co source. The maximum deviation from the calculated linear function is about 0.12 Gy in the dose range up to 80 Gy. The goal of medical applications was the superficial dose measurement in afterloading brachytherapy during the radiotherapy course in

  16. Specification of brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    1984-10-01

    BCRU recommends that the following specification of gamma-ray brachytherapy sources be adopted. Unless otherwise stated, the output of a cylindrical source should be specified in air kerma rate at a point in free space at a distance of 1 m from the source on the radial plane of symmetry, i.e. the plane bisecting the active length and perpendicular to the cylindrical axis of the source. For a wire source the output should be specified for a 1 cm length. For any other construction of source, the point at which the output is specified should be stated. It is also recommended that the units in which the air kerma rate is expressed should be micrograys per hour (..mu..Gy/h).

  17. Brachytherapy in vulvar cancer: analysis of 18 patients

    International Nuclear Information System (INIS)

    Frezza, G.; Baldissera, A.; Bernardi, L.; Bunkheila, F.; Galuppi, A.; Salvi, F.

    1996-01-01

    INTRODUCTION: Vulvar cancer is a rather common neoplasm in elderly patients. Surgery, followed eventually by postoperative radiotherapy, is the treatment of choice. The results of exclusive radiotherapy (external beam irradiation and/or brachytherapy) are not well defined and in the recent literature only small series are reported. Radiotherapy however is the only therapeutic option in patients who are not fit for radical surgery. It is thus necessary to review its indications and its modalities. PATIENTS METHODS AND RESULTS: From 1990 to 1994 18 pts with a diagnosis of squamous cell carcinoma of the vulva have been submitted to brachytherapy. Age ranged from 60 to 92 years (mean age 76, 1 ys). 14 pts were treated at diagnosis (11 pts) or for recurrent disease after surgery (3 pts). In 8 of them brachytherapy (total dose 35-45 Gy, dose rate: 0,4-0,78 Gy/h) was preceded by external beam irradiation (Co60 or electron beam, 40-50 Gy to primary and inguinal nodes); 6 pts were treated with brachytherapy alone (58-60 Gy; dose rate 0,44-0,63 Gy/h). 4 pts underwent to brachytherapy alone for local recurrence after surgery and postoperative radiotherapy (total dose 45-60 Gy; dose rate 0,37-0,49 Gy/h). Brachytherapy was always performed with 192 Ir. Plastic tubes (2 to 5 lines) were used for single plane implantation of small exophytic lesions limited to the labia (8 cases); a perineal template (10 cases) was employed in lesions extended to the vaginal mucosa or involving the clitoris or the area of the perineum. (10(14)) pts treated at diagnosis are alive and free from local recurrence after 11-48 mos. 3 of them, treated with brachytherapy alone, have presented a nodal recurrence in the groin after 14, 15 and 27 mos. respectively. All of them are alive and free from disease after surgery and external radiotherapy. None of the pts treated for recurrent disease after surgery + external beam radiotherapy has achieved a local control. CONCLUSION: Brachytherapy alone or

  18. Development and evaluation of accelerated drug release testing methods for a matrix-type intravaginal ring.

    Science.gov (United States)

    Externbrink, Anna; Eggenreich, Karin; Eder, Simone; Mohr, Stefan; Nickisch, Klaus; Klein, Sandra

    2017-01-01

    Accelerated drug release testing is a valuable quality control tool for long-acting non-oral extended release formulations. Currently, several intravaginal ring candidates designed for the long-term delivery of steroids or anti-infective drugs are being in the developing pipeline. The present article addresses the demand for accelerated drug release methods for these formulations. We describe the development and evaluation of accelerated release methods for a steroid releasing matrix-type intravaginal ring. The drug release properties of the formulation were evaluated under real-time and accelerated test conditions. Under real-time test conditions drug release from the intravaginal ring was strongly affected by the steroid solubility in the release medium. Under sufficient sink conditions that were provided in release media containing surfactants drug release was Fickian diffusion driven. Both temperature and hydro-organic dissolution media were successfully employed to accelerate drug release from the formulation. Drug release could be further increased by combining the temperature effect with the application of a hydro-organic release medium. The formulation continued to exhibit a diffusion controlled release kinetic under the investigated accelerated conditions. Moreover, the accelerated methods were able to differentiate between different prototypes of the intravaginal ring that exhibited different release profiles under real-time test conditions. Overall, the results of the present study indicate that both temperature and hydro-organic release media are valid parameters for accelerating drug release from the intravaginal ring. Variation of either a single or both parameters yielded release profiles that correlated well with real-time release. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. MO-E-BRD-02: Accelerated Partial Breast Irradiation in Brachytherapy: Is Shorter Better?

    International Nuclear Information System (INIS)

    Todor, D.

    2015-01-01

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  20. MO-E-BRD-02: Accelerated Partial Breast Irradiation in Brachytherapy: Is Shorter Better?

    Energy Technology Data Exchange (ETDEWEB)

    Todor, D. [Virginia Commonwealth University (United States)

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  1. MO-E-BRD-03: Intra-Operative Breast Brachytherapy: Is One Stop Shopping Best?

    International Nuclear Information System (INIS)

    Libby, B.

    2015-01-01

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  2. Premature ejaculation: bother and intravaginal ejaculatory latency time in Iran.

    Science.gov (United States)

    Zargooshi, Javaad

    2009-12-01

    Complaints of premature ejaculation (PE) and its repercussions are culture-dependent. To report the measured intravaginal ejaculatory latency time (IELT) and the impact of PE in Kermanshah, Iran. From November 1996 through October 2008, 3,458 patients presented to us with self-diagnosed PE. In the first visit, after obtaining a psychosocial and sexual history, PE-specific bother was self-rated by the patients and the patients were advised to measure their IELTs over the next 2-3 weeks. In the second visit, the measured IELTs were reported by the patients. Patients' measured IELT and bother score. Age range was 17-80 years (mean 34.1, standard deviation [SD] 9.1, median 32). Sixty-five percent were married. Primary and secondary PE was reported by 2,105 (60.8%) and 1,353 (39.1%) patients, respectively. Occasional PE was reported by 36 (0.01%). Of those with multiple partners, 6% had partner-specific PE. IELT distribution was positively skewed. Anteportal ejaculation was reported by 97 (2.8%). In 3,458 self-reported PE patients, IELT was 1-15 seconds in 542 (15.7%), 16-30 seconds in 442 (12.8%), 31-60 seconds in 978 (28.3%), > 1 2 5 minutes in 136 (3.9%). IELTs of IELT and bother (r = -0.607) was highly negative, with shorter IELTs being correlated with more bother. Six hundred forty-three patients (18.6%) always consumed opium to lengthen their IELTs. All 21 patients who started to use Tramadol as a PE treatment became addicted to it. Of 168 divorced couples due to PE, 23 divorced because the sexually dissatisfied wives became involved in extramarital affairs. Applying the Diagnostic and Statistical Manual of Mental Disorders criteria for PE and a cutoff IELT point of IELTs of longer than 2 minutes, the patients with occasional PE, and the patients who reported no personal bother, of 3,458 self-reported PE patients, 2,571 (74.3%) had PE. Including the 97 patients with anteportal ejaculation, arithmetic mean IELT in 2,571 patients was 45.87 seconds, SD 36.1, median

  3. Erectile function after prostate brachytherapy

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Anderson, Richard L.; Kurko, Brian S.; Lief, Jonathan H.; Allen, Zachariah A.

    2005-01-01

    Purpose: To evaluate erectile function after permanent prostate brachytherapy using a validated patient-administered questionnaire and to determine the effect of multiple clinical, treatment, and dosimetric parameters on penile erectile function. Methods and materials: A total of 226 patients with preimplant erectile function determined by the International Index of Erectile Function (IIEF) questionnaire underwent permanent prostate brachytherapy in two prospective randomized trials between February 2001 and January 2003 for clinical Stage T1c-T2c (2002 American Joint Committee on Cancer) prostate cancer. Of the 226 patients, 132 were potent before treatment and, of those, 128 (97%) completed and returned the IIEF questionnaire after brachytherapy. The median follow-up was 29.1 months. Potency was defined as an IIEF score of ≥13. The clinical, treatment, and dosimetric parameters evaluated included patient age; preimplant IIEF score; clinical T stage; pretreatment prostate-specific antigen level; Gleason score; elapsed time after implantation; preimplant nocturnal erections; body mass index; presence of hypertension or diabetes mellitus; tobacco consumption; the volume of the prostate gland receiving 100%, 150%, and 200% of the prescribed dose (V 100/150/200 ); the dose delivered to 90% of the prostate gland (D 90 ); androgen deprivation therapy; supplemental external beam radiotherapy (EBRT); isotope; prostate volume; planning volume; and radiation dose to the proximal penis. Results: The 3-year actuarial rate of potency preservation was 50.5%. For patients who maintained adequate posttreatment erectile function, the preimplant IIEF score was 29, and in patients with brachytherapy-related ED, the preimplant IIEF score was 25. The median time to the onset of ED was 5.4 months. After brachytherapy, the median IIEF score was 20 in potent patients and 3 in impotent patients. On univariate analysis, the preimplant IIEF score, patient age, presence of nocturnal

  4. Multihelix rotating shield brachytherapy for cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dadkhah, Hossein [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States); Kim, Yusung; Flynn, Ryan T., E-mail: ryan-flynn@uiowa.edu [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Wu, Xiaodong [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 and Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States)

    2015-11-15

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D{sub 90} of HR-CTV) were the two metrics used as the basis for evaluation and

  5. Evaluation of resins for use in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Luiz Claudio F.M. Garcia; Ferraz, Wilmar Barbosa; Chrcanovic, Bruno Ramos; Santos, Ana Maria M., E-mail: ferrazw@cdtn.b, E-mail: amms@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Brachytherapy is an advanced cancer treatment where radioactive seeds or sources are placed near or directly into the tumor thus reducing the radiation exposure in the surrounding healthy tissues. Prostate cancer can be treated with interstitial brachytherapy in initial stage of the disease in which tiny radioactive seeds with cylindrical geometry are used. Several kinds of seeds have been developed in order to obtain a better dose distribution around them and with a lower cost manufacturing. These seeds consist of an encapsulation, a radionuclide carrier, and X-ray marker. Among the materials that have potential for innovation in the construction of seeds, biocompatible resins appear as an important option. In this paper, we present some characterization results with Fourier transform infrared spectroscopic (FTIR) and ultraviolet-visible spectroscopy (UV-vis) performed on two types of resins in which curing temperatures for each one were varied as also the results of coatings with these resins under titanium substrates. Interactions of these resins in contact with the simulated body fluid were evaluated by atomic force microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. (author)

  6. Qualitative and quantitative intravaginal targeting: Key to anti-HIV-1 microbicide delivery from test tube to in vivo success

    CSIR Research Space (South Africa)

    Pillay, V

    2012-06-01

    Full Text Available employed. We hereby propose a thorough scientific qualitative and quantitative investigation of important aspects involved in HIV-1 transmission as a prerequisite for microbicide delivery. Intravaginal targeting of HIV-1 increases the chances of microbicide...

  7. SU-E-T-552: Monte Carlo Calculation of Correction Factors for a Free-Air Ionization Chamber in Support of a National Air-Kerma Standard for Electronic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mille, M; Bergstrom, P [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    2015-06-15

    Purpose: To use Monte Carlo radiation transport methods to calculate correction factors for a free-air ionization chamber in support of a national air-kerma standard for low-energy, miniature x-ray sources used for electronic brachytherapy (eBx). Methods: The NIST is establishing a calibration service for well-type ionization chambers used to characterize the strength of eBx sources prior to clinical use. The calibration approach involves establishing the well-chamber’s response to an eBx source whose air-kerma rate at a 50 cm distance is determined through a primary measurement performed using the Lamperti free-air ionization chamber. However, the free-air chamber measurements of charge or current can only be related to the reference air-kerma standard after applying several corrections, some of which are best determined via Monte Carlo simulation. To this end, a detailed geometric model of the Lamperti chamber was developed in the EGSnrc code based on the engineering drawings of the instrument. The egs-fac user code in EGSnrc was then used to calculate energy-dependent correction factors which account for missing or undesired ionization arising from effects such as: (1) attenuation and scatter of the x-rays in air; (2) primary electrons escaping the charge collection region; (3) lack of charged particle equilibrium; (4) atomic fluorescence and bremsstrahlung radiation. Results: Energy-dependent correction factors were calculated assuming a monoenergetic point source with the photon energy ranging from 2 keV to 60 keV in 2 keV increments. Sufficient photon histories were simulated so that the Monte Carlo statistical uncertainty of the correction factors was less than 0.01%. The correction factors for a specific eBx source will be determined by integrating these tabulated results over its measured x-ray spectrum. Conclusion: The correction factors calculated in this work are important for establishing a national standard for eBx which will help ensure that dose

  8. High Infection Rates for Adult Macaques after Intravaginal or Intrarectal Inoculation with Zika Virus

    Science.gov (United States)

    Nalca, Aysegul; Rossi, Franco D.; Miller, Lynn J.; Wiley, Michael R.; Perez-Sautu, Unai; Washington, Samuel C.; Norris, Sarah L.; Wollen-Roberts, Suzanne E.; Shamblin, Joshua D.; Kimmel, Adrienne E.; Bloomfield, Holly A.; Valdez, Stephanie M.; Sprague, Thomas R.; Principe, Lucia M.; Bellanca, Stephanie A.; Cinkovich, Stephanie S.; Lugo-Roman, Luis; Cazares, Lisa H.; Pratt, William D.; Palacios, Gustavo F.; Bavari, Sina; Pitt, M. Louise; Nasar, Farooq

    2017-01-01

    Unprotected sexual intercourse between persons residing in or traveling from regions with Zika virus transmission is a risk factor for infection. To model risk for infection after sexual intercourse, we inoculated rhesus and cynomolgus macaques with Zika virus by intravaginal or intrarectal routes. In macaques inoculated intravaginally, we detected viremia and virus RNA in 50% of macaques, followed by seroconversion. In macaques inoculated intrarectally, we detected viremia, virus RNA, or both, in 100% of both species, followed by seroconversion. The magnitude and duration of infectious virus in the blood of macaques suggest humans infected with Zika virus through sexual transmission will likely generate viremias sufficient to infect competent mosquito vectors. Our results indicate that transmission of Zika virus by sexual intercourse might serve as a virus maintenance mechanism in the absence of mosquito-to-human transmission and could increase the probability of establishment and spread of Zika virus in regions where this virus is not present. PMID:28548637

  9. High Infection Rates for Adult Macaques after Intravaginal or Intrarectal Inoculation with Zika Virus.

    Science.gov (United States)

    Haddow, Andrew D; Nalca, Aysegul; Rossi, Franco D; Miller, Lynn J; Wiley, Michael R; Perez-Sautu, Unai; Washington, Samuel C; Norris, Sarah L; Wollen-Roberts, Suzanne E; Shamblin, Joshua D; Kimmel, Adrienne E; Bloomfield, Holly A; Valdez, Stephanie M; Sprague, Thomas R; Principe, Lucia M; Bellanca, Stephanie A; Cinkovich, Stephanie S; Lugo-Roman, Luis; Cazares, Lisa H; Pratt, William D; Palacios, Gustavo F; Bavari, Sina; Pitt, M Louise; Nasar, Farooq

    2017-08-01

    Unprotected sexual intercourse between persons residing in or traveling from regions with Zika virus transmission is a risk factor for infection. To model risk for infection after sexual intercourse, we inoculated rhesus and cynomolgus macaques with Zika virus by intravaginal or intrarectal routes. In macaques inoculated intravaginally, we detected viremia and virus RNA in 50% of macaques, followed by seroconversion. In macaques inoculated intrarectally, we detected viremia, virus RNA, or both, in 100% of both species, followed by seroconversion. The magnitude and duration of infectious virus in the blood of macaques suggest humans infected with Zika virus through sexual transmission will likely generate viremias sufficient to infect competent mosquito vectors. Our results indicate that transmission of Zika virus by sexual intercourse might serve as a virus maintenance mechanism in the absence of mosquito-to-human transmission and could increase the probability of establishment and spread of Zika virus in regions where this virus is not present.

  10. Pregnancy outcome of home intravaginal insemination in couples with unconsummated marriage

    Directory of Open Access Journals (Sweden)

    Kaberi Banerjee

    2017-01-01

    Full Text Available Unconsummated marriage are mainly due to vaginismus or erectile dysfunction. They contribute to about 5% of couples in an infertility clinic. Their incidence is increasing in the metropolitan cities because of stressful lifestyles. Many of couples are advised intrauterine insemination as fertility treatment. However, home insemination is a simple, inexpensive and effective way of achieving pregnancy in such couples. We present the first study to document pregnancy rates of artificial home intravaginal insemination in couples with unconsummated marriage. Aim: To assess the pregnancy rates (PR with intravaginal insemination (IVI by couples with nonconsummation of marriage. Setting: Infertility outpatient clinic, New Delhi. Design: Retrospective analysis. Material and Methods: 55 couples of unconsummated marriage were evaluated in a period of two years. Group 1 contains 29 patients aged between 20 to 33 years; group 2 includes 14 patients aged between 33 to 36 years and group 3 includes 12 patients aged more than 36 years. Result(s: Unconsummated marriage was caused by vaginismus in 67% of the cases, erectile dysfunction in 22% and premature ejaculation in 11%. Clinical pregnancy rate was 69% in group 1; 43% in group 2 and 25% in group 3 after 6 cycles of AI. Conclusion(s: Intravaginal insemination is a simple, short, economical, effective and painless procedure for conception in nonconsummation of marriage.

  11. Pregnancy Outcome of Home Intravaginal Insemination in Couples with Unconsummated Marriage

    Science.gov (United States)

    Banerjee, Kaberi; Singla, Bhavana

    2017-01-01

    Unconsummated marriage are mainly due to vaginismus or erectile dysfunction. They contribute to about 5% of couples in an infertility clinic. Their incidence is increasing in the metropolitan cities because of stressful lifestyles. Many of couples are advised intrauterine insemination as fertility treatment. However, home insemination is a simple, inexpensive and effective way of achieving pregnancy in such couples. We present the first study to document pregnancy rates of artificial home intravaginal insemination in couples with unconsummated marriage. Aim: To assess the pregnancy rates (PR) with intravaginal insemination (IVI) by couples with nonconsummation of marriage. Setting: Infertility outpatient clinic, New Delhi. Design: Retrospective analysis. Material and Methods: 55 couples of unconsummated marriage were evaluated in a period of two years. Group 1 contains 29 patients aged between 20 to 33 years; group 2 includes 14 patients aged between 33 to 36 years and group 3 includes 12 patients aged more than 36 years. Result(s): Unconsummated marriage was caused by vaginismus in 67% of the cases, erectile dysfunction in 22% and premature ejaculation in 11%. Clinical pregnancy rate was 69% in group 1; 43% in group 2 and 25% in group 3 after 6 cycles of AI. Conclusion(s): Intravaginal insemination is a simple, short, economical, effective and painless procedure for conception in nonconsummation of marriage. PMID:29430157

  12. Intravaginal hormonal contraception for women of reproductive age with excessive body mass

    Directory of Open Access Journals (Sweden)

    I. B. Gridina

    2015-12-01

    Full Text Available There are a number of disadvantages inherent in all oral hormonal contraceptives: need for daily administration, fluctuations of hormone levels throughout the day, metabolism in the gastrointestinal tract, the effect of the first passage through the liver. All this became a prerequisite to the creation of prolonged oral hormonal methods of contraception, which would be devoid of these shortcomings. One of such method of hormonal contraception is intravaginal hormonal system. The aim was to determine the safety and efficacy of its use in women of reproductive age with overweight. 43 women were included. State of lipid metabolism, changes of the hemostatic system, blood pressure and weight fluctuations in the past 6 months of using intravaginal hormonal contraceptive system were studied. Results. It is established that hormonal intravaginal contraceptive ring gives minimal metabolic effects. Conclusion. This suggests that this ring can be used successfully in patients with excessive body mass, because there is no effect of the ring on hemostasis, lipid metabolism and body weight.

  13. Polyurethane intravaginal ring for controlled delivery of dapivirine, a nonnucleoside reverse transcriptase inhibitor of HIV-1.

    Science.gov (United States)

    Gupta, Kavita M; Pearce, Serena M; Poursaid, Azadeh E; Aliyar, Hyder A; Tresco, Patrick A; Mitchnik, Mark A; Kiser, Patrick F

    2008-10-01

    Women-controlled methods for prevention of male-to-female sexual transmission of HIV-1 are urgently needed. Providing inhibitory concentrations of HIV-1 reverse transcriptase inhibitors to impede the replication of the virus in the female genital tissue offers a mechanism for prophylaxis of HIV-1. To this end, an intravaginal ring device that can provide long duration delivery of dapivirine, a nonnucleoside reverse transcriptase inhibitor of HIV-1, was developed utilizing a medical-grade polyether urethane. Monolithic intravaginal rings were fabricated and sustained release with cumulative flux linear with time was demonstrated under sink conditions for a period of 30 days. The release rate was directly proportional to the amount of drug loaded. Another release study conducted for a week utilizing liposome dispersions as sink conditions, to mimic the partitioning of dapivirine into vaginal tissue, also demonstrated release rates constant with time. These results qualify polyether urethanes for development of intravaginal rings for sustained delivery of microbicidal agents. (c) 2008 Wiley-Liss, Inc. and the American Pharmacists Association

  14. Epoxy resins used to seal brachytherapy seed

    International Nuclear Information System (INIS)

    Ferreira, Natalia Carolina Camargos; Ferraz, Wilmar Barbosa; Reis, Sergio Carneiro dos; Santos, Ana Maria Matildes dos

    2013-01-01

    Prostate cancer treatment with brachytherapy is recommended for patients with cancer at an early stage. In this treatment, small radioactive seeds are implanted directly in the prostate gland. These seeds are composed at least of one radionuclide carrier and an X-ray marker enclosed within a metallic tube usually sealed by laser process. This process is expensive and, furthermore, it can provoke a partial volatilization of the radionuclide and change the isotropy in dose distribution around the seed. In this paper, we present a new sealing process using epoxy resin. Three kinds of resins were utilized and characterized by scanning electron microscopy (SEM), energy dispersive X ray (EDS) and by differential scanning calorimetry (DSC) after immersion in simulated body fluid (SBF) and in sodium iodine solution (NaI). The sealing process showed excellent potential to replace the sealing laser usually employed. (author)

  15. SU-D-19A-05: The Dosimetric Impact of Using Xoft Axxent® Electronic Brachytherapy Source TG-43 Dosimetry Parameters for Treatment with the Xoft 30 Mm Diameter Vaginal Applicator

    Energy Technology Data Exchange (ETDEWEB)

    Simiele, S; Micka, J; Culberson, W; DeWerd, L [University of WI-Madison/ADCL, Madison, WI (United States)

    2014-06-01

    Purpose: A full TG-43 dosimetric characterization has not been performed for the Xoft Axxent ® electronic brachytherapy source (Xoft, a subsidiary of iCAD, San Jose, CA) within the Xoft 30 mm diameter vaginal applicator. Currently, dose calculations are performed using the bare-source TG-43 parameters and do not account for the presence of the applicator. This work focuses on determining the difference between the bare-source and sourcein- applicator TG-43 parameters. Both the radial dose function (RDF) and polar anisotropy function (PAF) were computationally determined for the source-in-applicator and bare-source models to determine the impact of using the bare-source dosimetry data. Methods: MCNP5 was used to model the source and the Xoft 30 mm diameter vaginal applicator. All simulations were performed using 0.84p and 0.03e cross section libraries. All models were developed based on specifications provided by Xoft. The applicator is made of a proprietary polymer material and simulations were performed using the most conservative chemical composition. An F6 collision-kerma tally was used to determine the RDF and PAF values in water at various dwell positions. The RDF values were normalized to 2.0 cm from the source to accommodate the applicator radius. Source-in-applicator results were compared with bare-source results from this work as well as published baresource results. Results: For a 0 mm source pullback distance, the updated bare-source model and source-in-applicator RDF values differ by 2% at 3 cm and 4% at 5 cm. The largest PAF disagreements were observed at the distal end of the source and applicator with up to 17% disagreement at 2 cm and 8% at 8 cm. The bare-source model had RDF values within 2.6% of the published TG-43 data and PAF results within 7.2% at 2 cm. Conclusion: Results indicate that notable differences exist between the bare-source and source-in-applicator TG-43 simulated parameters. Xoft Inc. provided partial funding for this work.

  16. About brachytherapy for the handling of cancer

    International Nuclear Information System (INIS)

    Campos, Tarcisio P.R.; Silva, Nilton O.; Damaso, Renato S.; Costa, Helder R.; Borges, Paulo H.R.; Mendes, Bruno M.

    2000-01-01

    The technique of brachytherapy is argued in this article. The 'hardware' and 'necessary software' for the handling are summarily presented. Being the macro-dosimetry an important stage in the radiation therapy procedure, a simplified method of doses evaluation in conventional brachytherapy is presented. In an illustrative form, isodoses of a three-dimensional distribution of linear sources are drawn on a digitalized X-ray picture, exemplifying the handling of breast brachytherapy by sources of iridium

  17. Physical aspects of radioisotope brachytherapy

    International Nuclear Information System (INIS)

    1967-01-01

    The present report represents an attempt to provide, within a necessarily limited compass, an authoritative guide to all important physical aspects of the use of sealed gamma sources in radiotherapy. Within the report, reference is made wherever necessary to the more extensive but scattered literature on this subject. While this report attempts to cover all the physical aspects of radioisotope 'brachytherapy' it does not, of course, deal exhaustively with any one part of the subject. 384 refs, 3 figs, 6 tabs

  18. Rectourethral fistula following LDR brachytherapy.

    Science.gov (United States)

    Borchers, Holger; Pinkawa, Michael; Donner, Andreas; Wolter, Timm P; Pallua, Norbert; Eble, Michael J; Jakse, Gerhard

    2009-01-01

    Modern LDR brachytherapy has drastically reduced rectal toxicity and decreased the occurrence of rectourethral fistulas to <0.5% of patients. Therefore, symptoms of late-onset sequelae are often ignored initially. These fistulas cause severe patient morbidity and require interdisciplinary treatment. We report on the occurrence and management of a rectourethral fistula which occurred 4 years after (125)I seed implantation. Copyright 2009 S. Karger AG, Basel.

  19. Radiation safety and gynaecological brachytherapy

    International Nuclear Information System (INIS)

    Crawford, L.

    1985-01-01

    In 1983, the Radiation Control Section of the South Australian Health Commission conducted an investigation into radiation safety practices in gynaecological brachytherapy. Part of the investigation included a study of the transportation of radioactive sources between hospitals. Several deficiences in radiation safety were found in the way these sources were being transported. New transport regulations came into force in South Australia in July 1984 and since then there have been many changes in the transportation procedure

  20. Risk analysis of brachytherapy events

    International Nuclear Information System (INIS)

    Buricova, P.; Zackova, H.; Hobzova, L.; Novotny, J.; Kindlova, A.

    2005-01-01

    For prevention radiological events it is necessary to identify hazardous situation and to analyse the nature of committed errors. Though the recommendation on the classification and prevention of radiological events: Radiological accidents has been prepared in the framework of Czech Society of Radiation Oncology, Biology and Physics and it was approved by Czech regulatory body (SONS) in 1999, only a few reports have been submitted up to now from brachytherapy practice. At the radiotherapy departments attention has been paid more likely to the problems of dominant teletherapy treatments. But in the two last decades the usage of brachytherapy methods has gradually increased because .nature of this treatment well as the possibilities of operating facility have been completely changed: new radionuclides of high activity are introduced and sophisticate afterloading systems controlled by computers are used. Consequently also the nature of errors, which can occurred in the clinical practice, has been changing. To determine the potentially hazardous parts of procedure the so-called 'process tree', which follows the flow of entire treatment process, has been created for most frequent type of applications. Marking the location of errors on the process tree indicates where failures occurred and accumulation of marks along branches show weak points in the process. Analysed data provide useful information to prevent medical events in brachytherapy .The results strength the requirements given in Recommendations of SONS and revealed the need for its amendment. They call especially for systematic registration of the events. (authors)

  1. Definitive Brachytherapy for Kaposi's Sarcoma

    International Nuclear Information System (INIS)

    Williams, A.; Ezzell, G.; Zalupski, M.; Fontanesi, J.

    1996-01-01

    Purpose: To assess the efficacy and possible complications in patients diagnosed with Kaposi's sarcoma and treated with definitive brachytherapy. Methods and Materials: Between January, 1995 and December, 1995, four patients with Kaposi's sarcoma (KS) were treated with brachytherapy. Three patients, all with positive HIV status were treated using Iridium 192 (Ir-192) sources via a high-dose rate remote afterloader. One patient with endemic KS was treated using the application of catheters loaded with Californium 252. Eight sites were treated and included scalp, feet, nose, penis, hand, neck, and back. Dose rate for Ir-192 was 330cGy/fx to a total dose of 990cGy. The Californium was delivered as 100nGy/b.i.d. to a total dose of 900nGy. Follow-up as ranged from 2-6 months. Results: All four patients remain alive. Seven of eight sites have had complete clinical response and each patient has reported durable pain relief that has not subsided through last follow-up of 1/96. Two of eight sites, both treated with surface mold technique with Californium 252 developed moist desquamation. The remaining six sites did not demonstrate significant toxicity. Conclusion: Brachytherapy can offer Kaposi's sarcoma patients results that are equivalent to external beam radiation therapy, with minimal complications, a shorter treatment time and potential cost effectiveness

  2. Interstitial prostate brachytherapy. LDR-PDR-HDR

    International Nuclear Information System (INIS)

    Kovacs, Gyoergy; Hoskin, Peter

    2013-01-01

    The first comprehensive overview of interstitial brachytherapy for the management of local or locally advanced prostate cancer. Written by an interdisciplinary team who have been responsible for the successful GEC-ESTRO/EAU Teaching Course. Discusses in detail patient selection, the results of different methods, the role of imaging, and medical physics issues. Prostate brachytherapy has been the subject of heated debate among surgeons and the proponents of the various brachytherapy methods. This very first interdisciplinary book on the subject provides a comprehensive overview of innovations in low dose rate (LDR), high dose rate (HDR), and pulsed dose rate (PDR) interstitial brachytherapy for the management of local or locally advanced prostate cancer. In addition to detailed chapters on patient selection and the use of imaging in diagnostics, treatment guidance, and implantation control, background chapters are included on related medical physics issues such as treatment planning and quality assurance. The results obtained with the different treatment options and the difficult task of salvage treatment are fully discussed. All chapters have been written by internationally recognized experts in their fields who for more than a decade have formed the teaching staff responsible for the successful GEC-ESTRO/EAU Prostate Brachytherapy Teaching Course. This book will be invaluable in informing residents and others of the scientific background and potential of modern prostate brachytherapy. It will also prove a useful source of up-to-date information for those who specialize in prostate brachytherapy or intend to start an interstitial brachytherapy service.

  3. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8(+) T cell priming in response to intravaginal immunization.

    Science.gov (United States)

    Seavey, Matthew M; Mosmann, Tim R

    2009-04-14

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8(+) T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APCs) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8(+) T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8(+) T cell priming after insemination or vaginal vaccination.

  4. Estradiol-induced vaginal mucus inhibits antigen penetration and CD8+ T cell priming in response to intravaginal immunization

    Science.gov (United States)

    Seavey, Matthew M.; Mosmann, Tim R.

    2010-01-01

    Although vaginal immunization has been explored as a strategy to induce mucosal immunity in the female reproductive tract, this site displays unique immunological features that probably evolved to inhibit anti-paternal T cell responses after insemination to allow successful pregnancy. We previously demonstrated that estradiol, which induces an estrus-like state, prevented CD8+ T cell priming during intravaginal immunization of mice. We now show that estradiol prevented antigen loading of vaginal antigen presenting cells (APC) after intravaginal immunization. Histological examination confirmed that estradiol prevented penetration of peptide antigen into the vaginal wall. Removal of the estradiol-induced mucus barrier by mucinase partially restored antigen loading of vaginal APC and CD8+ T cell proliferation in vivo. The estradiol-induced mucus barrier may thus prevent exposure to antigens delivered intravaginally, supplementing additional estradiol-dependent mechanism(s) that inhibit CD8+ T cell priming after insemination or vaginal vaccination. PMID:19428849

  5. Uso de un dispositivo intravaginal para el control del estro en yeguas

    OpenAIRE

    Wilde, Oscar R; de la Vega, Adolfo C; L. Cruz, María

    2002-01-01

    Un dispositivo intravaginal de uso bovino (PRID) conteniendo progesterona de lenta liberación, fue evaluado en once yeguas de la raza Peruano de Paso con el fin de sincronizar sus celos. El dispositivo fue instalado tal como es presentado comercialmente para bovinos y se mantuvo in situ por un lapso de doce días, al cabo de los cuales fue retirado sin mayores complicaciones. Manifestaciones de celo fueron observadas a las 24 h después del retiro del PRID, con su más alta incidencia (50%) a la...

  6. Paddle-based rotating-shield brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yunlong; Xu, Weiyu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M. [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Dadkhah, Hossein [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center, Iowa City, Iowa 52242 (United States); Wu, Xiaodong, E-mail: xiaodong-wu@uiowa.edu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

    2015-10-15

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm{sup 3} (D{sub 2cm{sup 3}}) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy{sub 3}, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D{sub 90} increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy{sub 10}, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D{sub 90}, compared to D-RSBT, were 16

  7. High dose rate brachytherapy for oral cancer

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Koizumi, Masahiko; Ogawa, Kazuhiko; Furukawa, Souhei

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. (author)

  8. High dose rate brachytherapy for oral cancer.

    Science.gov (United States)

    Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer.

  9. Qualitative and quantitative analysis of bacteria from vaginitis associated with intravaginal implants in ewes following estrus synchronization

    OpenAIRE

    Carlos Otávio de Paula Vasconcelos; Felipe Zandonadi Brandão; Gabriel Martins; Bruno Penna; Joanna Maria Gonçalves de Souza-Fabjan; Walter Lilenbaum

    2016-01-01

    ABSTRACT: This study evaluated the presence of vaginitis and the bacterial load associated with different intravaginal implants in ewes. Twenty-four Dorper and crossbred ewes were allocated into three groups and received intravaginal implant containing 0.3g progesterone (CIDR(r)), 60mg MAP or sponges without progesterone (CONTROL) for six days. Then, CIDR and MAP treated-ewes received 12.5mg dinoprost and 300IU eCG. Vaginal mucus samples were collected at four times: before device insertion, ...

  10. Balancing the efficacy and safety of misoprostol: a meta-analysis comparing 25 versus 50 micrograms of intravaginal misoprostol for the induction of labour.

    Science.gov (United States)

    McMaster, K; Sanchez-Ramos, L; Kaunitz, A M

    2015-03-01

    The optimal dose of misoprostol for the induction of labour remains uncertain. To compare the efficacy and safety of 25 versus 50 micrograms of intravaginal misoprostol tablets for the induction of labour and cervical ripening. We performed electronic and manual searches to identify relevant randomised trials. The efficacy outcomes assessed were rates of vaginal delivery within 24 hours, delivery within one dose, and oxytocin augmentation, and interval to delivery. The safety outcomes assessed were incidences of tachysystole, hyperstimulation, caesarean delivery, cesarean delivery for non-reassuring fetal heart rate (FHR), operative vaginal delivery, abnormal 5-minute Apgar score, abnormal cord gas values, admission to a neonatal intensive care unit (NICU), and meconium passage. Thirteen studies (1945 women) were included. Relative risk (RR) and 95% confidence intervals (CI) were calculated using fixed-effects and random-effects models. We found that 25 micrograms was less efficacious, with lower rates of delivery after one dose (RR 0.59; 95% CI 0.39-0.88) and vaginal delivery within 24 hours (RR 0.88; 95% CI 0.79-0.96), and with increased rates of oxytocin augmentation (RR 1.54, 95% CI 1.36-1.75). We noted an improved safety profile with 25 micrograms, however, with decreased rates of tachysystole (RR 0.46; 95% CI 0.35-0.61), hyperstimulation (RR 0.5; 95% CI 0.31-0.78), caesarean deliveries for non-reassuring FHR (RR 0.67; 95% CI 0.52-0.87), NICU admissions (RR 0.63; 95% CI 0.4-0.98), and meconium passage (RR 0.65; 95% CI 0.45-0.96). Although 50 micrograms of intravaginal misoprostol may be more efficacious, safety concerns make the 25-microgram dose preferable. © 2014 Royal College of Obstetricians and Gynaecologists.

  11. Determination of the dose of traffic in HDR brachytherapy with ALANINE/R PE technique

    International Nuclear Information System (INIS)

    Guzman Calcina, C. S.; Chen, F.; Almeida, A. de; Baffa, O.

    2001-01-01

    It determines, experimentally, the dose of traffic in brachytherapy for High Dose Rate (HDR), using for the first-time the Electronic Paramagnetic Resonance (EPR) technique with alanine detectors. The value obtained is the published next to obtained using lithium fluoride thermoluminescent dosimeters [es

  12. American Brachytherapy Society recommendations for reporting morbidity after prostate brachytherapy

    International Nuclear Information System (INIS)

    Nag, Subir; Ellis, Rodney J.; Merrick, Gregory S.; Bahnson, Robert; Wallner, Kent; Stock, Richard

    2002-01-01

    Purpose: To standardize the reporting of brachytherapy-related prostate morbidity to guide ongoing clinical practice and future investigations. Methods: Members of the American Brachytherapy Society (ABS) with expertise in prostate brachytherapy performed a literature review and, guided by their clinical experience, formulated specific recommendations for reporting on morbidity related to prostate brachytherapy. Results: The ABS recommends using validated, patient-administered health-related quality-of-life instruments for the determination of baseline and follow-up data regarding bowel, urinary, and sexual function. Both actuarial and crude incidences should be reported, along with the temporal resolution of specific complications, and correlated with the doses to the normal tissues. The International Prostate Symptom Score is recommended to assess urinary morbidity, and any dysuria, gross hematuria, urinary retention, incontinence, or medication use should be quantified. Likewise, the ''Sexual Health Inventory for Men,'' which includes the specific erectile questions of the International Index of Erectile Function, is the preferred instrument for reporting sexual function, and the loss of sexual desire, incidence of hematospermia, painful orgasm (orgasmalgia), altered orgasm intensity, decreased ejaculatory volume, use of erectile aids, and use of hormones for androgen deprivation should be quantified. The ABS recommends adoption of the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer acute and late radiation morbidity scoring scheme for reporting rectal morbidity and noting the incidence of rectal steroid, laser, or antidiarrheal use. Conclusion: It is important to focus on health-related quality-of-life issues in the treatment of prostate cancer, because the control rates are very similar between appropriate treatment modalities. The ABS recommends using the International Prostate Symptom Score, International Index of

  13. Intravaginal testicular torsion in newborns. To fix or not to fix the contralateral testis?

    Directory of Open Access Journals (Sweden)

    G. Bordin

    2013-10-01

    Full Text Available Scrotal swelling suggesting testicular torsion is a rare urological emergency which requires a clinical urgent evaluation and most of the times must be managed surgically. In newborns it can occur in the postnatal period, usually within the twenty-eighth day of life, or more frequently in utero, during the descent of the testis into the scrotum. Usually its poor fixedness allows the testis an abnormal mobility inside the scrotum, configuring the framework of extravaginal torsion. On the contrary during the perinatal period a twist that takes place inside the tunica vaginalis, known as intravaginal torsion, is extremely uncommon and only few cases are well documented in the literature. Authors present a rare case of intravaginal testicular torsion occurred in perinatal period. In this situation only the early surgical exploration of the scrotum may allow the rescue of the gonad, although in rare cases. Timing of surgical treatment and need for contralateral testicular fixation remain controversial. However since the anatomical defect of the tunica vaginalis can be bilateral the surgical fixation even of the contralateral testis is important, now or later, in order to prevent any future torsion of this gonad. The authors also present a brief review of recent literature on the subject.

  14. Evaluation of the acceptability of intravaginal prasterone ovule administration using an applicator.

    Science.gov (United States)

    Montesino, Marlene; Labrie, Fernand; Archer, David F; Zerhouni, Jaâfar; Côté, Isabelle; Lavoie, Lyne; Beauregard, Adam; Martel, Céline; Vaillancourt, Mario; Moyneur, Erick; Balser, John

    2016-01-01

    The objective of the study is to evaluate the acceptability of the intravaginal administration of ovules/suppositories of DHEA (dehydroepiandrosterone, prasterone) for the treatment of vulvovaginal atrophy (VVA) in women with moderate to severe dyspareunia who were administered daily for 12 weeks intravaginal 0.50% (6.5 mg) DHEA or placebo. There were a total of 373 women in the per-protocol population who responded to the questionnaire for both treatment groups. While it was planned that the applicator would be evaluated as suitable if at least 80% of participants have a global score  ≤ 2 units, 99% and 100% of participants had a score  ≤ 2 units in the placebo and DHEA groups, respectively, for the global score (mean of 5 questions). When asked about like and dislike the technique of drug administration, 284 comments were positive, while 114 women gave no comment. About 92-94% of women indicated that they were very confident to be able use the applicator successfully in the future. The survey shows a high degree of satisfaction and of confidence to use the applicator successfully in the future.

  15. Engineering a degradable polyurethane intravaginal ring for sustained delivery of dapivirine.

    Science.gov (United States)

    Kaur, Manpreet; Gupta, Kavita M; Poursaid, Azadeh E; Karra, Prasoona; Mahalingam, Alamelu; Aliyar, Hyder A; Kiser, Patrick F

    2011-06-01

    We describe the engineering of a degradable intravaginal ring (IVR) for the delivery of the potent HIV-1 reverse transcriptase inhibitor dapivirine. The degradable polymer used in fabricating the device incorporated poly(caprolactone) ester blocks in a poly(tetramethylene ether) glycol ABA type polyurethane backbone. The polymer was designed to maintain its structure for 1 month during usage and then degrade in the environment post-disposal. In vitro release of dapivirine showed zero-order kinetics for up to 1 month and significant levels of drug release into engineered vaginal tissue. The mechanical properties of the degradable IVR were comparable to those of a widely used contraceptive intravaginal ring upon exposure to simulated vaginal conditions. Incubation under simulated vaginal conditions for a month caused minimal degradation with minimal effect on the mechanical properties of the ring and polymer. The cytotoxicity evaluation of the drug-loaded IVRs against Vk2/E6E7 human vaginal epithelial cells, Lactobacillus jensenii, and engineered vaginal tissue constructs showed the degradable polyurethane to be non-toxic. In vitro evaluation of inflammatory potential monitored through the levels of inflammatory cytokines IL-8, IL-1α, IL-6, IL-1β, and MIP-3α when engineered EpiVaginal™ tissue was incubated with the polyurethanes suggested that the degradable polyurethane was comparable to commercial medical grade polyurethane. These results are encouraging for further development of this degradable IVR for topical vaginal delivery of microbicides.

  16. Intra-vaginal Zinc Oxide Tetrapod Nanoparticles as Novel Immunoprotective Agents against Genital Herpes

    Science.gov (United States)

    Antoine, Thessicar E.; Hadigal, Satvik R.; Yakoub, Abraam; Mishra, Yogendra K.; Bhattacharya, Palash; Haddad, Christine; Valyi-Nagy, Tibor; Adelung, Rainer; Prabhakar, Bellur S.; Shukla, Deepak

    2016-01-01

    Virtually all efforts to generate an effective protection against the life-long, recurrent genital infections caused by Herpes simplex virus-2 (HSV-2) have failed. Apart from sexual transmission, the virus can also be transmitted from mothers to neonates, and is a key facilitator of HIV co-acquisition. Here, we uncover a nanoimmunotherapy using specially designed Zinc Oxide Tetrapod Nanoparticles (ZOTEN) with engineered oxygen vacancies. We demonstrate that ZOTEN, when used intravaginally as a microbicide, is an effective suppressor of HSV-2 genital infection in female BALB/c mice. The strong HSV-2 trapping ability of ZOTEN significantly reduced the clinical signs of vaginal infection and effectively decreased animal mortality. In parallel, ZOTEN promoted the presentation of bound HSV-2 virions to mucosal antigen presenting cells, enhancing T cell- mediated and antibody-mediated responses to the infection, and thereby, suppressing a re-infection. We also found that ZOTEN exhibits strong adjuvant-like properties, which is highly comparable to alum, a commonly used adjuvant. Overall, our study provides very first evidence for the protective efficacy of an intravaginal microbicide/vaccine or microbivac platform against primary and secondary female genital herpes infections. PMID:27183601

  17. Physical aspects of endovascular brachytherapy

    International Nuclear Information System (INIS)

    Kirisits, C.

    2001-11-01

    Restenosis is severely limiting the outcome of vascular interventions. In several clinical trials endovascular brachytherapy has shown to reduce the restenosis rate. Local radiotherapy to the injured vessel wall is a promising new type of treatment in order to inhibit a complex wound healing process resulting in cell proliferation and re-obstruction of the treated vessel. Treatment planning has to be based on the dose distribution in the vicinity of the sources used. Source strength was determined in terms of air kerma rate for gamma nuclides (Iridium-192) and absorbed dose to water at reference distance of 2 mm for beta nuclides (Strontium-90/Yttrium-90, Phosphor-32), respectively. Radial dose profiles and the Reference Isodose Length (RIL) were determined using the EGSnrc code and GafChromic film. Good agreement was found between both methods. In order to treat the entire clinical target length, the (RIL) is an essential value during treatment planning. Examples are described for different levels of treatment planing including recommendations for optimal choice and positioning of the radioactive devices inside the artery. IVUS based treatment planning is illustrated with superposition of isodoses on cross-sectional images. A calculation model for radioactive stents is presented in order to determine dose volume histograms in a retrospective analysis. Radiation protection issues for endovascular brachytherapy are discussed in detail. Personal dose for the involved personnel is estimated based on calculations and measurements. Beta ray dosimetry is performed with suitable detectors. In order to estimate the exposure to the patient the dose to organs at risk is calculated and compared to the dose from angiography. There is an additional radiation exposure to patients and personnel caused by endovascular brachytherapy, but the values are much smaller than those caused by diagnostic angiography. (author)

  18. Performance profiling for brachytherapy applications

    Science.gov (United States)

    Choi, Wonqook; Cho, Kihyeon; Yeo, Insung

    2018-05-01

    In many physics applications, a significant amount of software (e.g. R, ROOT and Geant4) is developed on novel computing architectures, and much effort is expended to ensure the software is efficient in terms of central processing unit (CPU) time and memory usage. Profiling tools are used during the evaluation process to evaluate the efficiency; however, few such tools are able to accommodate low-energy physics regions. To address this limitation, we developed a low-energy physics profiling system in Geant4 to profile the CPU time and memory of software applications in brachytherapy applications. This paper describes and evaluates specific models that are applied to brachytherapy applications in Geant4, such as QGSP_BIC_LIV, QGSP_BIC_EMZ, and QGSP_BIC_EMY. The physics range in this tool allows it to be used to generate low energy profiles in brachytherapy applications. This was a limitation in previous studies, which caused us to develop a new profiling tool that supports profiling in the MeV range, in contrast to the TeV range that is supported by existing high-energy profiling tools. In order to easily compare the profiling results between low-energy and high-energy modes, we employed the same software architecture as that in the SimpliCarlo tool developed at the Fermilab National Accelerator Laboratory (FNAL) for the Large Hadron Collider (LHC). The results show that the newly developed profiling system for low-energy physics (less than MeV) complements the current profiling system used for high-energy physics (greater than TeV) applications.

  19. Guidelines for comprehensive quality assurance in brachytherapy

    International Nuclear Information System (INIS)

    Goldson, A.L.; Nibhanupudy, J.R.

    1984-01-01

    Brachytherapy treatment techniques can provide significant improvement in local control and overall survival, but only when quality assurance can be guaranteed. To establish brachytherapy quality assurance, basic requirements for three predetermined subdivisions of clinical institutions will be forwarded. These are: (1) centers having minimum requirements to provide brachytherapy, (2) intermediate centers such as regional or community hospitals, and (3) optimal centers such as university hospital and cancer centers. This presentation will highlight personnel needs, equipment requirements, academic activities, clinical experience with these systems and proposed quality assurance guidelines

  20. Transport and Biodistribution of Dendrimers Across Human Fetal Membranes: Implications for Intravaginal Administration of Dendrimers

    Science.gov (United States)

    Menjoge, Anupa R.; Navath, Raghavendra S.; Asad, Abbas; Kannan, Sujatha; Kim, Chong Jai; Romero, Roberto; Kannan, Rangaramanujam M.

    2010-01-01

    Dendrimers are emerging as promising topical antimicrobial agents, and as targeted nanoscale drug delivery vehicles. Topical intravaginal antimicrobial agents are prescribed to treat the ascending genital infections in pregnant women. The fetal membranes separate the extra-amniotic space and fetus. The purpose of the study is to determine if the dendrimers can be selectively used for local intravaginal application to pregnant women without crossing the membranes into the fetus. In the present study, the transport and permeability of PAMAM (poly(amidoamine)) dendrimers, across human fetal membrane (using a side-by-side diffusion chamber), and its biodistribution (using immunofluorescence) are evaluated ex-vivo. Transport across human fetal membranes (from the maternal side) was evaluated using Fluorescein (FITC), an established transplacental marker (positive control, size~ 400 Da) and fluorophore-tagged G4-PAMAM dendrimers (~ 16 kDa). The fluorophore-tagged G4-PAMAM dendrimers were synthesized and characterized using 1H NMR, MALDI TOF-MS and HPLC analysis. Transfer was measured across the intact fetal membrane (chorioamnion), and the separated chorion and amnion layers. Over a five hour period, the dendrimer transport across all the three membranes was less than transport of FITC was relatively fast with as much as 49% transport across the amnion. The permeability of FITC (7.9 × 10-7 cm2/s) through the chorioamnion was 7-fold higher than that of the dendrimer (5.8 × 10-8 cm2/s). The biodistribution showed that the dendrimers were largely present in interstitial spaces in the decidual stromal cells and the chorionic trophoblast cells (in 2.5 to 4 h) and surprisingly, to a smaller extent internalized in nuclei of trophoblast cells and nuclei and cytoplasm of stromal cells. Passive diffusion and paracellular transport appear to be the major route for dendrimer transport. The overall findings further suggest that entry of drugs conjugated to dendrimers would be

  1. Novel intravaginal nanomedicine for the targeted delivery of saquinavir to CD4+ immune cells

    Directory of Open Access Journals (Sweden)

    Yang S

    2013-08-01

    Full Text Available Sidi Yang,1,2 Yufei Chen,1,2 Kaien Gu,1,2 Alicia Dash,1,2 Casey L Sayre,1 Neal M Davies,1 Emmanuel A Ho1,2 1Faculty of Pharmacy, 2Laboratory for Drug Delivery and Biomaterials, University of Manitoba, Winnipeg, MB, Canada Abstract: The goal of this study was to develop and characterize an intravaginal nanomedicine for the active targeted delivery of saquinavir (SQV to CD4+ immune cells as a potential strategy to prevent or reduce HIV infection. The nanomedicine was formulated into a vaginal gel to provide ease in self-administration and to enhance retention within the vaginal tract. SQV-encapsulated nanoparticles (SQV-NPs were prepared from poly(lactic-co-glycolic acid(PLGA and conjugated to antihuman anti-CD4 antibody. Antibody-conjugated SQV-NPs (Ab-SQV-NPs had an encapsulation efficiency (EE% of 74.4% ± 3.7% and an antibody conjugation efficiency (ACE% of 80.95% ± 1.10%. Over 50% of total loaded SQV was released from NPs over 3 days. NPs were rapidly taken up by Sup-T1 cells, with more than a twofold increase in the intracellular levels of SQV when delivered by Ab-SQV-NPs in comparison to controls 1 hour post-treatment. No cytotoxicity was observed when vaginal epithelial cells were treated for 24 hours with drug-free Ab-NPs (1,000 µg/mL, 1% HEC placebo gel (200 mg/mL, or 1% HEC gel loaded with drug-free Ab-NPs (5 mg NPs/g gel, 200 mg/mL of gel mixture. Overall, we described an intravaginal nanomedicine that is nontoxic and can specifically deliver SQV into CD4+ immune cells. This platform may demonstrate potential utility in its application as postexposure prophylaxis for the treatment or reduction of HIV infection, but further studies are required. Keywords: nanoparticles, saquinavir, antibody conjugation, intravaginal gel, HIV/AIDS, microbicide

  2. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Concomitant chemoradiotherapy with high dose rate brachytherapy as a definitive treatment modality for locally advanced cervical cancer. T Refaat, A Elsaid, N Lotfy, K Kiel, W Small Jr, P Nickers, E Lartigau ...

  3. Comprehensive brachytherapy physical and clinical aspects

    CERN Document Server

    Baltas, Dimos; Meigooni, Ali S; Hoskin, Peter J

    2013-01-01

    Modern brachytherapy is one of the most important oncological treatment modalities requiring an integrated approach that utilizes new technologies, advanced clinical imaging facilities, and a thorough understanding of the radiobiological effects on different tissues, the principles of physics, dosimetry techniques and protocols, and clinical expertise. A complete overview of the field, Comprehensive Brachytherapy: Physical and Clinical Aspects is a landmark publication, presenting a detailed account of the underlying physics, design, and implementation of the techniques, along with practical guidance for practitioners. Bridging the gap between research and application, this single source brings together the technological basis, radiation dosimetry, quality assurance, and fundamentals of brachytherapy. In addition, it presents discussion of the most recent clinical practice in brachytherapy including prostate, gynecology, breast, and other clinical treatment sites. Along with exploring new clinical protocols, ...

  4. Evolution of brachytherapy for prostate carcinoma

    International Nuclear Information System (INIS)

    Qin Lan

    2005-01-01

    Brachytherapy is one of the most main management to prostate carcinoma. This method has been rapidly accepted in clinical application since it is a convenient, little-traumatic, and outpatient therapy. With the development of techniques of production of radio-seeds, imaging modality and three-dimensional radiotherapy plan system, brachytherapy has been made a virtually progress in improving curative-effect and reducing damage to surrounding normal tissue. (authors)

  5. Long duration mild temperature hyperthermia and brachytherapy.

    Science.gov (United States)

    Armour, E P; Raaphorst, G P

    2004-03-01

    Combining long duration mild temperature hyperthermia (LDMH) and low dose-rate (LDR) brachytherapy to enhance therapeutic killing of cancer cells was proposed many years ago. The cellular and tumour research that supports this hypothesis is presented in this review. Research describing LDMH interaction with pulsed brachytherapy and high dose-rate brachytherapy using clinically relevant parameters are compared with LDMH/LDR brachytherapy. The mechanism by which LDMH sensitizes LDR has been established as the inhibition of sublethal damage repair. The molecular mechanisms have been shown to involve DNA repair enzymes, but the exact nature of these processes is still under investigation. The relative differences between LDMH interactions with human and rodent cells are presented to help in the understanding of possible roles of LDMH in clinical application. The role of LDMH in modifying tumour blood flow and its possible role in LDR sensitization of tumours is also presented. The positive aspects of LDMH-brachytherapy for clinical application are sixfold; (1) the thermal goals (temperature, time and volume) are achievable with currently available technology, (2) the hyperthermia by itself has no detectable toxic effects, (3) thermotolerance appears to play a minor if any role in radiation sensitization, (4) TER of around 2 can be expected, (5) hypoxic fraction may be decreased due to blood flow modification and (6) simultaneous chemotherapy may also be sensitized. Combined LDMH and brachytherapy is a cancer therapy that has established biological rationale and sufficient technical and clinical advancements to be appropriately applied. This modality is ripe for clinical testing.

  6. An intravaginal ring that releases the NNRTI MIV-150 reduces SHIV transmission in macaques.

    Science.gov (United States)

    Singer, Rachel; Mawson, Paul; Derby, Nina; Rodriguez, Aixa; Kizima, Larisa; Menon, Radhika; Goldman, Daniel; Kenney, Jessica; Aravantinou, Meropi; Seidor, Samantha; Gettie, Agegnehu; Blanchard, James; Piatak, Michael; Lifson, Jeffrey D; Fernández-Romero, José A; Robbiani, Melissa; Zydowsky, Thomas M

    2012-09-05

    Microbicides may prevent HIV and sexually transmitted infections (STIs) in women; however, determining the optimal means of delivery of active pharmaceutical ingredients remains a major challenge. We previously demonstrated that a vaginal gel containing the non-nucleoside reverse transcriptase inhibitor MIV-150 partially protected macaques from SHIV-RT (simian/HIV reverse transcriptase) infection, and the addition of zinc acetate rendered the gel significantly protective. We test the activity of MIV-150 without the addition of zinc acetate when delivered from either ethylene vinyl acetate (EVA) or silicone intravaginal rings (IVRs). MIV-150 was successfully delivered, because it was detected in vaginal fluids and tissues by radioimmunoassay in pharmacokinetic studies. Moreover, EVA IVRs significantly protected macaques from SHIV-RT infection. Our results demonstrate that MIV-150-containing IVRs have the potential to prevent HIV infection and highlight the possible use of IVRs for delivering drugs that block HIV and other STIs.

  7. Gluteo-vaginal fistula after posterior intravaginal slingplasty: a case report.

    Science.gov (United States)

    Grynberg, Michael; Teyssedre, Jacques; Staerman, Frederic

    2009-07-01

    In patients with posthysterectomy prolapse of the vaginal vault, the posterior intravaginal slingplasty (posterior IVS, Tyco Healthcare, USA) has been suggested as an alternative to traditional vaginal vault suspensions. The goal of this technique is to recreate the uterosacral ligaments and to reinforce the rectovaginal fascia with the use of prosthetic material. We report the case of a 53-year-old woman with a history of 27 months of perineal suppurative discharge after she underwent a vaginal vault prolapse and rectocele repair using a posterior IVS (Tyco Healthcare, USA). The IVS tape was reinforced by interposing a rectovaginal monofilament polypropylene mesh (Parietex, Sofradim, France). Imaging studies and surgical exploration confirmed infection of the IVS mesh with the formation of a gluteo-vaginal fistula while the rectovaginal mesh was intact.

  8. Changes in the prostacyctin sensitivity of thrombocytes after intravaginal radium irradiation of patients with corpus carcinoma

    International Nuclear Information System (INIS)

    Schneider, A.

    1987-01-01

    The goal of this work was to investigate, to what extent the platelet sensitivity in comparison to prostacyclin (PGI 2 ) should be seen as a responsible factor in the increase of the thrombosis rate. For this blood was examined from 22 patients with corpus carcinoma who had received an intravaginal Radium implant with a radiation dose of 960 mgeh to over 24 h. These patients were compared to a control group of 21 clinically healthy women. Even before the radiation therapy there was an increased aggregation rate of the thrombocytes in the carcinoma patients as well as a reduced sensitivity to PGI 2 . Under irradiation there was an even greater decrease in the sensitivity of the thrombocytes to PGI 2 . The aggregation speed increase statistically significantly and the number of thrombocytes decreased during the Radium irradiation. After the giving of heparin the sensitivity of the thrombocytes to PGI 2 sank strongly. (orig./MG) [de

  9. Intravaginal boric acid: is it an alternative therapeutic option for vaginal trichomoniasis?

    Science.gov (United States)

    Thorley, Nicola; Ross, Jonathan

    2017-12-09

    Trichomoniasis, caused by Trichomonas vaginalis (TV), is the most common curable sexually transmitted infection worldwide. Current guidance in the UK is to treat TV with a nitroimidazole antibiotic. The high prevalence of TV, high rate of antibiotic resistance and limited tolerability to nitroimidazoles suggest that alternative treatment regimens are needed. Intravaginal boric acid (BA) has been used safely for the treatment of candida vulvovaginitis and bacterial vaginosis, and in vitro studies suggest BA is active against TV. We review the evidence for the efficacy of BA in patients with TV. MEDLINE, EMBASE, CINAHL, AMED, HMIC and BNI and Grey literature databases, The Cochrane Library, Trial Registers, conference abstracts and proceedings were searched. Inclusion criteria were women aged 16 years or over with microbiological confirmation of TV infection and using BA as treatment. There were no restrictions on language, publication date or study design. The in vitro evidence for BA activity against TV was also reviewed. No randomised controlled trials or case series were found. Four case reports demonstrated TV clearance with BA using a variety of dose regimens (dose 600 mg alternate nights to 600 mg two times per day; duration 1-5 months). In vitro studies suggest that BA has activity against TV which is independent of its effect on pH. Further evaluation of BA for the treatment of uncomplicated TV is required, but it may be useful when therapeutic options are limited. If shown to be safe and effective, intravaginal BA might provide a well-tolerated alternative anti-infective treatment which reduces community exposure to systemic antibiotics. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. The American Brachytherapy Society recommendations for low-dose-rate brachytherapy for carcinoma of the cervix

    International Nuclear Information System (INIS)

    Nag, Subir; Chao, Clifford; Erickson, Beth; Fowler, Jeffery; Gupta, Nilendu; Martinez, Alvaro; Thomadsen, Bruce

    2002-01-01

    Purpose: This report presents guidelines for using low-dose-rate (LDR) brachytherapy in the management of patients with cervical cancer. Methods: Members of the American Brachytherapy Society (ABS) with expertise in LDR brachytherapy for cervical cancer performed a literature review, supplemented by their clinical experience, to formulate guidelines for LDR brachytherapy of cervical cancer. Results: The ABS strongly recommends that radiation treatment for cervical carcinoma (with or without chemotherapy) should include brachytherapy as a component. Precise applicator placement is essential for improved local control and reduced morbidity. The outcome of brachytherapy depends, in part, on the skill of the brachytherapist. Doses given by external beam radiotherapy and brachytherapy depend upon the initial volume of disease, the ability to displace the bladder and rectum, the degree of tumor regression during pelvic irradiation, and institutional practice. The ABS recognizes that intracavitary brachytherapy is the standard technique for brachytherapy for cervical carcinoma. Interstitial brachytherapy should be considered for patients with disease that cannot be optimally encompassed by intracavitary brachytherapy. The ABS recommends completion of treatment within 8 weeks, when possible. Prolonging total treatment duration can adversely affect local control and survival. Recommendations are made for definitive and postoperative therapy after hysterectomy. Although recognizing that many efficacious LDR dose schedules exist, the ABS presents suggested dose and fractionation schemes for combining external beam radiotherapy with LDR brachytherapy for each stage of disease. The dose prescription point (point A) is defined for intracavitary insertions. Dose rates of 0.50 to 0.65 Gy/h are suggested for intracavitary brachytherapy. Dose rates of 0.50 to 0.70 Gy/h to the periphery of the implant are suggested for interstitial implant. Use of differential source activity or

  11. Acute vasculitis after endovascular brachytherapy

    International Nuclear Information System (INIS)

    Fajardo L-G, Luis F.; Prionas, Stavros D.; Kaluza, Grzegorz L.; Raizner, Albert E.

    2002-01-01

    Purpose: Angioplasty effectively relieves coronary artery stenosis but is often followed by restenosis. Endovascular radiation (β or γ) at the time of angioplasty prevents restenosis in a large proportion of vessels in swine (short term) and humans (short and long term). Little information is available about the effects of this radiation exposure beyond the wall of the coronary arteries. Methods and Materials: Samples were obtained from 76 minipigs in the course of several experiments designed to evaluate endovascular brachytherapy: 76 of 114 coronary arteries and 6 of 12 iliac arteries were exposed to endovascular radiation from 32 P sources (35 Gy at 0.5 mm from the intima). Two-thirds of the vessels had angioplasty or stenting. The vessels were systematically examined either at 28 days or at 6 months after radiation. Results: We found an unexpected lesion: acute necrotizing vasculitis in arterioles located ≤2.05 mm from the target artery. It was characterized by fibrinoid necrosis of the wall, often associated with lymphocytic exudates or thrombosis. Based on the review of perpendicular sections of tissue samples, the arterioles had received between 6 and 40 Gy. This arteriolar vasculitis occurred at 28 days in samples from 51% of irradiated coronary arteries and 100% of irradiated iliac arteries. By 6 months, the incidence of acute vasculitis decreased to 24% around the coronary arteries. However, at that time, healing vasculitis was evident, often with luminal narrowing, in 46% of samples. Vasculitis was not seen in any of 44 samples from unirradiated vessels (0%) and had no relation to angioplasty, stenting, or their sequelae. This radiation-associated vasculitis in the swine resembles the localized lymphocytic vasculitis that we have reported in tissues of humans exposed to external radiation. On the other hand, it is quite different from the various types of systemic vasculitis that occur in nonirradiated humans. Conclusion: Endoarterial brachytherapy

  12. Monte Carlo Simulations Validation Study: Vascular Brachytherapy Beta Sources

    International Nuclear Information System (INIS)

    Orion, I.; Koren, K.

    2004-01-01

    During the last decade many versions of angioplasty irradiation treatments have been proposed. The purpose of this unique brachytherapy is to administer a sufficient radiation dose into the vein walls in order to prevent restonosis, a clinical sequel to balloon angioplasty. The most suitable sources for this vascular brachytherapy are the β - emitters such as Re-188, P-32, and Sr-90/Y-90, with a maximum energy range of up to 2.1 MeV [1,2,3]. The radioactive catheters configurations offered for these treatments can be a simple wire [4], a fluid filled balloon or a coated stent. Each source is differently positioned inside the blood vessel, and the emitted electrons ranges therefore vary. Many types of sources and configurations were studied either experimentally or with the use of the Monte Carlo calculation technique, while most of the Monte Carlo simulations were carried out using EGS4 [5] or MCNP [6]. In this study we compared the beta-source absorbed-dose versus radial-distance of two treatment configurations using MCNP and EGS4 simulations. This comparison was aimed to discover the differences between the MCNP and the EGS4 simulation code systems in intermediate energies electron transport

  13. Serotonin Transporter Promoter Region (5-HTTLPR) Polymorphism is Associated with the Intravaginal Ejaculation Latency Time in Dutch Men with Lifelong Premature Ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K. C.; Bakker, Steven C.; Réthelyi, Janos; Zwinderman, Aeilko H.; Touw, Daan J.; Olivier, Berend; Waldinger, Marcel D.

    2009-01-01

    Introduction. Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central

  14. The 5-HT₁A receptor CG polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K C; van Schaik, R; Zwinderman, Aeilko H; Olivier, Berend|info:eu-repo/dai/nl/073067199; Waldinger, Marcel D|info:eu-repo/dai/nl/163958564

    INTRODUCTION: Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 min, and has been postulated as a neurobiological dysfunction related to diminished serotonergic neurotransmission with 5-HT₁A receptor hyperfunction and

  15. Serotonin transporter promoter region (5-HTTLPR) polymorphism is associated with the intravaginal ejaculation latency time in Dutch men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K C; Bakker, Steven C; Réthelyi, Janos; Zwinderman, Aeilko H; Touw, Daan J; Olivier, Berend; Waldinger, Marcel D

    INTRODUCTION: Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 minute, and has been postulated as a neurobiological dysfunction with genetic vulnerability for the short IELTs, related to disturbances of central

  16. Navigation system for interstitial brachytherapy

    International Nuclear Information System (INIS)

    Strassmann, G.; Kolotas, C.; Heyd, R.

    2000-01-01

    The purpose of the stud was to develop a computed tomography (CT) based electromagnetic navigation system for interstitial brachytherapy. This is especially designed for situations when needles have to be positioned adjacent to or within critical anatomical structures. In such instances interactive 3D visualisation of the needle positions is essential. The material consisted of a Polhemus electromagnetic 3D digitizer, a Pentium 200 MHz laptop and a voice recognition for continuous speech. In addition, we developed an external reference system constructed of Perspex which could be positioned above the tumour region and attached to the patient using a non-invasive fixation method. A specially designed needle holder and patient bed were also developed. Measurements were made on a series of phantoms in order to study the efficacy and accuracy of the navigation system. The mean navigation accuracy of positioning the 20.0 cm length metallic needles within the phantoms was in the range 2.0-4.1 mm with a maximum of 5.4 mm. This is an improvement on the accuracy of a CT-guided technique which was in the range 6.1-11.3 mm with a maximum of 19.4 mm. The mean reconstruction accuracy of the implant geometry was 3.2 mm within a non-ferromagnetic environment. We found that although the needles were metallic this did not have a significant influence. We also found for our experimental setups that the CT table and operation table non-ferromagnetic parts had no significant influence on the navigation accuracy. This navigation system will be a very useful clinical tool for interstitial brachytherapy applications, particularly when critical structures have to be avoided. It also should provide a significant improvement on our existing technique

  17. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of brachytherapy source accountability. 35.2406... Records of brachytherapy source accountability. (a) A licensee shall maintain a record of brachytherapy source accountability required by § 35.406 for 3 years. (b) For temporary implants, the record must...

  18. 10 CFR 35.406 - Brachytherapy sources accountability.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Brachytherapy sources accountability. 35.406 Section 35....406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all times... area. (c) A licensee shall maintain a record of the brachytherapy source accountability in accordance...

  19. Calculation of integrated biological response in brachytherapy

    International Nuclear Information System (INIS)

    Dale, Roger G.; Coles, Ian P.; Deehan, Charles; O'Donoghue, Joseph A.

    1997-01-01

    Purpose: To present analytical methods for calculating or estimating the integrated biological response in brachytherapy applications, and which allow for the presence of dose gradients. Methods and Materials: The approach uses linear-quadratic (LQ) formulations to identify an equivalent biologically effective dose (BED eq ) which, if applied to a specified tissue volume, would produce the same biological effect as that achieved by a given brachytherapy application. For simple geometrical cases, BED multiplying factors have been derived which allow the equivalent BED for tumors to be estimated from a single BED value calculated at a dose reference point. For more complex brachytherapy applications a voxel-by-voxel determination of the equivalent BED will be more accurate. Equations are derived which when incorporated into brachytherapy software would facilitate such a process. Results: At both high and low dose rates, the BEDs calculated at the dose reference point are shown to be lower than the true values by an amount which depends primarily on the magnitude of the prescribed dose; the BED multiplying factors are higher for smaller prescribed doses. The multiplying factors are less dependent on the assumed radiobiological parameters. In most clinical applications involving multiple sources, particularly those in multiplanar arrays, the multiplying factors are likely to be smaller than those derived here for single sources. The overall suggestion is that the radiobiological consequences of dose gradients in well-designed brachytherapy treatments, although important, may be less significant than is sometimes supposed. The modeling exercise also demonstrates that the integrated biological effect associated with fractionated high-dose-rate (FHDR) brachytherapy will usually be different from that for an 'equivalent' continuous low-dose-rate (CLDR) regime. For practical FHDR regimes involving relatively small numbers of fractions, the integrated biological effect to

  20. Externally placed vs intravaginally positioned radio frequency coils for quantitative spin-spin relaxometry of ovarian follicular fluid

    International Nuclear Information System (INIS)

    Sarty, G.E.; Baerwald, A.R.; Loewy, J.; Pierson, R.A.

    2005-01-01

    To evaluate different imaging protocols, especially with respect to radio frequency (RF) receiver coil location, for Their suitability in providing least squares derived quantitative T 2 values of ovarian follicular fluid for investigations of basic ovarian physiology. Methods: The ovaries of 10 women were imaged via magnetic resonance imaging (MRI) using externally positioned and intravaginally placed RF receiver coils. Half-Fourier acquisition with single-shot turbo spin-echo (HASTE), multiple-echo T 2 , Dixon, turbo spin-echo, and 3-dimensional (3D) fast imaging with steady-state precession (FISP) and time-reversed FISP (PSIF) sequences were used. Quantitative T 2 nuclear spin relaxation rate information from the ovarian follicles between data acquired with the external and intravaginal coils were compared. Additionally, the amount of ovarian follicle and corpora lutea structural detail visible was qualitatively assessed. Results: The T 2 computations indicated that there was no difference in the follicular fluid T 2 values or in the heterogeneity (spatial variance) of the T 2 values between data acquired with the external RF coil and date acquired with the intravaginal RF coil. The best sequences for the visualization of ovarian internal structure were the 3D PSIF sequences and the multiple-echo T 2 -weighted images, confirming our earlier imaging work on excised cow ovaries. Conclusion: It is best to use an externally placed RF coil for quantitative MRI study of ovarian physiology given the lack of difference in quantitative T 2 information and the difficulty associated with imaging the ovaries using an intravaginal RF probe. (author)

  1. Effect of intravaginal dehydroepiandrosterone (DHEA) on the female sexual function in postmenopausal women: ERC-230 open-label study.

    Science.gov (United States)

    Bouchard, Céline; Labrie, Fernand; Derogatis, Leonard; Girard, Ginette; Ayotte, Normand; Gallagher, John; Cusan, Leonello; Archer, David F; Portman, David; Lavoie, Lyne; Beauregard, Adam; Côté, Isabelle; Martel, Céline; Vaillancourt, Mario; Balser, John; Moyneur, Erick

    2016-03-01

    Intravaginal DHEA (dehydroepiandrosterone, prasterone), the exclusive precursor of androgens and estrogens in postmenopausal women, has previously been shown to improve all the domains of sexual function by a strictly local action in the vagina. The well recognized female sexual function index (FSFI) questionnaire was used in the present study. The long-term effect of 52-week treatment with daily intravaginal 0.50% (6.5 mg) DHEA was evaluated on the various domains of female sexual function using the FSFI questionnaire at baseline, Week 26 and Week 52. One hundred and fifty-four postmenopausal women with at least one mild to severe symptom of vulvovaginal atrophy (VVA) and who have completed the FSFI questionnaire at baseline and at least one post-baseline timepoint were included in the analysis. The FSFI domains desire, arousal, lubrication, orgasm, satisfaction and pain were increased by 28%, 49%, 115%, 51%, 41% and 108%, respectively (p<0.0001 for all parameters) at 52 weeks vs. baseline, while the total score was increased from 13.4±0.62 at baseline to 21.5±0.82 (+60%, p<0.0001) at 52 weeks. As the serum levels of DHEA and all its metabolites, including estradiol and testosterone, show no meaningful change, the present clinical data indicate a stimulatory effect of intravaginal DHEA through a strictly local action in agreement with the preclinical data showing that the androgens made locally from DHEA in the vagina induce an increase in local nerve density.

  2. Pregnancy and conception rate after two intravaginal inseminations with dog semen frozen either with 5% glycerol or 5% ethylene glycol.

    Science.gov (United States)

    Rota, Ada; Milani, C; Romagnoli, S; Zucchini, P; Mollo, A

    2010-03-01

    The primary goal of this study was to compare the effects of 5% ethylene glycol (EG) and 5% glycerol (G) on fertility of frozen-thawed dog semen following intravaginal insemination. The sperm-rich fraction of the ejaculate of three male dogs was collected, pooled and divided into two aliquots, and then frozen with a Tris-glucose-egg yolk-citric acid extender containing either 5% G or 5% EG. A total of 10 bitches were inseminated twice, five with G-frozen-thawed semen and five with EG-frozen-thawed semen; intravaginal inseminations were performed the 4th and the 5th day after the estimated LH peak; four straws, thawed in a 37 degrees C water bath for 1 min and diluted in a Tris buffer, were used for insemination (200 x 10(6) spermatozoa); the insemination dose was introduced in the cranial vagina of the bitch using a sterile plastic catheter. Ovariohysterectomy was performed in all bitches between days 29 and 31 after the calculated LH surge, and pregnancy status, and the number of conceptuses and corpora lutea were recorded. All bitches were pregnant. Neither the number of conceptuses, nor the ratio of conceptuses to corpora lutea (conception rate) was significantly different between groups. In this first screening, with a limited number of bitches, EG-frozen semen did not show a higher fertility than G-frozen semen when used for two intravaginal inseminations. Irrespective of the semen used, conception rate was 0.50.

  3. ACPSEM brachytherapy working group recommendations for quality assurance in brachytherapy

    International Nuclear Information System (INIS)

    Dempsey, Claire; Smith, Ryan; Nyathi, Thulani; Ceylan, Abdurrahman; Howard, Lisa; Patel, Virendra; Dam, Ras; Haworth, Annette

    2013-01-01

    The Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) Radiation Oncology Specialty Group (ROSG) formed a series of working groups in 2011 to develop recommendation papers for guidance of radiation oncology medical physics practice within the Australasian setting. These recommendations are intended to provide guidance for safe work practices and a suitable level of quality control without detailed work instructions. It is the responsibility of the medical physicist to ensure that locally available equipment and procedures are sufficiently sensitive to establish compliance to these recommendations. The recommendations are endorsed by the ROSG, have been subject to independent expert reviews and have also been approved by the ACPSEM Council. For the Australian audience, these recommendations should be read in conjunction with the Tripartite Radiation Oncology Practice Standards. This publication presents the recommendations of the ACPSEM Brachytherapy Working Group (BTWG) and has been developed in alignment with other international associations. However, these recommendations should be read in conjunction with relevant national, state or territory legislation and local requirements, which take precedence over the ACPSEM recommendation papers. It is hoped that the users of this and other ACPSEM recommendation papers will contribute to the development of future versions through the Radiation Oncology Specialty Group of the ACPSEM.

  4. Local anesthesia for prostate brachytherapy

    International Nuclear Information System (INIS)

    Wallner, Kent; Simpson, Colleen; Roof, James; Arthurs, Sandy; Korssjoen, Tammy; Sutlief, Steven

    1999-01-01

    Purpose: To demonstrate the technique and feasibility of prostate brachytherapy performed with local anesthesia only. Methods and Materials: A 5 by 5 cm patch of perineal skin and subcutaneous tissue is anesthetized by local infiltration of 10 cc of 1% lidocaine with epinephrine, using a 25-gauge 5/8-inch needle. Immediately following injection into the subcutaneous tissues, the deeper tissues, including the pelvic floor and prostate apex, are anesthetized by injecting 15 cc lidocaine solution with approximately 8 passes of a 20-gauge 1.0-inch needle. Following subcutaneous and peri-apical lidocaine injections, the patient is brought to the simulator suite and placed in leg stirrups. The transrectal ultrasound (TRUS) probe is positioned to reproduce the planning images and a 3.5- or 6.0-inch, 22-gauge spinal needle is inserted into the peripheral planned needle tracks, monitored by TRUS. When the tips of the needles reach the prostatic base, about 1 cc of lidocaine solution is injected in the intraprostatic track, as the needle is slowly withdrawn, for a total volume of 15 cc. The implants are done with a Mick Applicator, inserting and loading groups of two to four needles, so that a maximum of only about four needles are in the patient at any one time. During the implant procedure, an additional 1 cc of lidocaine solution is injected into one or more needle tracks if the patient experiences substantial discomfort. The total dose of lidocaine is generally limited to 500 mg (50 ml of 1% solution). Results: To date, we have implanted approximately 50 patients in our simulator suite, using local anesthesia. Patients' heart rate and diastolic blood pressure usually showed moderate changes, consistent with some discomfort. The time from first subcutaneous injection and completion of the source insertion ranged from 35 to 90 minutes. Serum lidocaine levels were below or at the low range of therapeutic. There has been only one instance of acute urinary retention in the

  5. Proficiency-based cervical cancer brachytherapy training.

    Science.gov (United States)

    Zhao, Sherry; Francis, Louise; Todor, Dorin; Fields, Emma C

    2018-04-25

    Although brachytherapy increases the local control rate for cervical cancer, there has been a progressive decline in its use. Furthermore, the training among residency programs for gynecologic brachytherapy varies considerably, with some residents receiving little to no training. This trend is especially concerning given the association between poor applicator placement and decline in local control. Considering the success of proficiency-based training in other procedural specialties, we developed and implemented a proficiency-based cervical brachytherapy training curriculum for our residents. Each resident placed tandem and ovoid applicators with attending guidance and again alone 2 weeks later using a pelvic model that was modified to allow for cervical brachytherapy. Plain films were taken of the pelvic model, and applicator placement quality was evaluated. Other evaluated metrics included retention of key procedural details, the time taken for each procedure and presession and postsession surveys to assess confidence. During the initial session, residents on average met 4.5 of 5 placement criteria, which improved to 5 the second session. On average, residents were able to remember 7.6 of the 8 key procedural steps. Execution time decreased by an average of 10.5%. Resident confidence with the procedure improved dramatically, from 2.6 to 4.6 of 5. Residents who had previously never performed a tandem and ovoid procedure showed greater improvements in these criteria than those who had. All residents strongly agreed that the training was helpful and wanted to participate again the following year. Residents participating in this simulation training had measurable improvements in the time to perform the procedure, applicator placement quality, and confidence. This curriculum is easy to implement and is of great value for training residents, and would be particularly beneficial in programs with low volume of cervical brachytherapy cases. Simulation programs could

  6. 137Cs - Brachytherapy sources : a technology scenario

    International Nuclear Information System (INIS)

    Varma, R.N.

    2001-01-01

    Cancer has emerged as one of the major cause of morbidity and mortality all over the world. India houses world's second largest population and registers 4-5 lakhs new cancer cases every year. Cancer of cervix is most common form of malignancy among Indian women. Radiation therapy, especially intracavity brachytherapy in conjunction with other modalities like surgery, chemotherapy has been found to be highly effective for the management and control of cervical carcinoma at all stages. A technology has been developed indigenously for the fabrication of 137 Cs sources for brachytherapy applications

  7. American brachytherapy society (ABS) consensus guidelines for brachytherapy of esophageal cancer

    International Nuclear Information System (INIS)

    Gaspar, Laurie E.; Nag, Subir; Herskovic, Arnold; Mantravadi, Rao; Speiser, Burton

    1997-01-01

    Introduction: There is wide variation in the indications, treatment regimens, and dosimetry for brachytherapy in the treatment of cancer of the esophagus. No guidelines for optimal therapy currently exist. Methods and Materials: Utilizing published reports and clinical experience, representatives of the Clinical Research Committee of the American Brachytherapy Society (ABS) formulated guidelines for brachytherapy in esophageal cancer. Results: Recommendations were made for brachytherapy in the definitive and palliative treatment of esophageal cancer. (A) Definitive treatment: Good candidates for brachytherapy include patients with unifocal thoracic adeno- or squamous cancers ≤ 10 cm in length, with no evidence of intra-abdominal or metastatic disease. Contraindications include tracheal or bronchial involvement, cervical esophagus location, or stenosis that cannot be bypassed. The esophageal brachytherapy applicator should have an external diameter of 6-10 mm. If 5FU-based chemotherapy and 45-50-Gy external beam are used, recommended brachytherapy is either: (i) HDR 10 Gy in two weekly fractions of 5 Gy each; or (ii) LDR 20 Gy in a single course at 0.4-1 Gy/hr. All doses are specified 1 cm from the midsource or middwell position. Brachytherapy should follow external beam radiation therapy and should not be given concurrently with chemotherapy. (B) Palliative treatment: Patients with adeno- or squamous cancers of the thoracic esophagus with distant metastases or unresectable local disease progression/recurrence after definitive radiation treatment should be considered for brachytherapy with palliative intent. After limited dose (30 Gy) EBRT, the recommended brachytherapy is either: (i) HDR 10-14 Gy in one or two fractions; or (ii) LDR 20-25 Gy in a single course at 0.4-1 Gy/hr. The need for external beam radiation in newly diagnosed patients with a life expectancy of less than 3 months is controversial. In these cases, HDR of 15-20 Gy in two to four fractions or

  8. Viability of neutron brachytherapy technique using Cf252 for tumors of salivary glands therapy

    International Nuclear Information System (INIS)

    Andrade, Lidia M.; Campos, Tarcisio P.R.

    2000-01-01

    Gland salivary tumors, although uncommon, present significant characteristics such as distant metastasis, recurrence and average survive of five year for treated patients. Those tumors presents low response to a conventional radiotherapy, photon and electron therapy; thus, this modality is associated with surgery. Fast neutron therapy has been presented better results in controlling the local tumor in comparison with conventional radiotherapy. Brachytherapy with Cf-252 presents an alternative treatment for tumors. Those radiotherapy technique are discussed and analyzed. (author)

  9. Static and dynamic MRI of a urinary control intra-vaginal device

    International Nuclear Information System (INIS)

    Maubon, A.J.; Boncoeur-Martel, M.P.; Juhan, V.; Rouanet, J.P.; Courtieu, C.R.; Thurmond, A.S.; Aubas, P.; Mares, P.

    2000-01-01

    The aim of this study was to describe by MRI, in dynamic conditions at rest and straining, the anatomical modifications induced by a commercially available intravaginal device (IVD) aimed at relieving female stress urinary incontinence. Ten female patients complaining of stress urinary incontinence (SUI) had pelvic MRI with static and dynamic sequences, without and with a self-inserted IVD. We studied positions and angulations of the IVD in the pelvis. Paired t-test allowed comparisons of: position of the bladder neck; urethral angulation with the pubis axis; position of the urethra; and posterior urethro-vesical angle (PUVA) without and with IVD. At rest, in ten of ten cases IVD laid cranial to the pubo-rectal muscle; with an average angulation of 95 ± 10 with the pubis axis, laterally tilted in three of ten cases. In maximum straining with IVD bladder neck descent was lower by an average of 5.2 ± 3.1 mm (p = 0.001), pubo-urethral angle opening was smaller by an average of 22 ± 20 (p = 0.015), and bladder neck to pubis distance was shorter by an average of 5.7 ± 4 mm. Posterior urethro-vesical angle was not significantly modified. Dynamic MRI allowed a non-invasive assessment of the mode of action of an IVD. The main modifications were a support of the bladder base and bladder neck, with a superior displacement of the urethra toward the pubis. (orig.)

  10. Intravaginal metronidazole gel versus metronidazole plus nystatin ovules for bacterial vaginosis: a randomized controlled trial.

    Science.gov (United States)

    Sanchez, Sixto; Garcia, Patricia J; Thomas, Katherine K; Catlin, Mary; Holmes, King K

    2004-12-01

    We compared metronidazole 0.75% gel (containing 37.5 mg metronidazole per dose) with ovules containing metronidazole 500 mg and nystatin 100,000 U, for intravaginal treatment of bacterial vaginosis (BV). In a single-blinded trial, symptomatic women with BV by both Amsel and Nugent criteria were randomly assigned to gel or ovules, once nightly for 5 nights, and asked to return 3 times after treatment. Analyses were intent-to-treat. Of 151 women with BV by both criteria at enrollment, 138 (91%) returned at least once. Product limit estimates for persistence or recurrence of BV at 14, 42, and 104 days were 20% (95% CI 10%-29%), 38% (95% CI 25%-48%), and 52% (95% CI 37%-63%) after gel treatment, and 4% (95% CI 0%-9%), 17% (95% CI 7%-26%), and 33% (95% CI 21%-46%) after ovule treatment ( P = .01). Among women without BV at first follow-up, subsequent intercourse without condoms independently predicted subsequent recurrence ( P Metronidazole/nystatin ovules were significantly more effective than metronidazole gel. Unprotected sex predicted recurrence after initial improvement.

  11. Development of polyether urethane intravaginal rings for the sustained delivery of hydroxychloroquine

    Science.gov (United States)

    Chen, Yufei; Traore, Yannick Leandre; Li, Amanda; Fowke, Keith R; Ho, Emmanuel A

    2014-01-01

    Hydroxychloroquine (HCQ) has been shown to demonstrate anti-inflammatory properties and direct anti-HIV activity. In this study, we describe for the first time the fabrication and in vitro evaluation of two types of intravaginal ring (IVR) devices (a surfaced-modified matrix IVR and a reservoir segmental IVR) for achieving sustained delivery (>14 days) of HCQ as a strategy for preventing male-to-female transmission of HIV. Both IVRs were fabricated by hot-melt injection molding. Surface-modified matrix IVRs with polyvinylpyrrolidone or poly(vinyl alcohol) coatings exhibited significantly reduced burst release on the first day (6.45% and 15.72% reduction, respectively). Reservoir IVR segments designed to release lower amounts of HCQ displayed near-zero-order release kinetics with an average release rate of 28.38 μg/mL per day for IVRs loaded with aqueous HCQ and 32.23 μg/mL per day for IVRs loaded with HCQ mixed with a rate-controlling excipient. Stability studies demonstrated that HCQ was stable in coated or noncoated IVRs for 30 days. The IVR segments had no significant effect on cell viability, pro-inflammatory cytokine production, or colony formation of vaginal and ectocervical epithelial cells. Both IVR systems may be suitable for the prevention of HIV transmission and other sexually transmitted infections. PMID:25336923

  12. Is there a correlation between intravaginal ejaculatory latency time and enuresis? An exploratory study.

    Science.gov (United States)

    Koyuncu, Hakan; Serefoglu, Ege Can; Karacay, Safak; Ozdemir, Ahmet Tunc; Kalkan, Mehmet; Yencilek, Faruk

    2014-01-01

    Premature ejaculation (PE) is the most common male sexual dysfunction. Monosymptomatic enuresis (ME) is nocturnal bed wetting, without any daytime symptoms. Recent clinical studies report an association between lifelong PE and ME. The purpose of this study was to compare the intravaginal ejaculatory time (IELT) between lifelong PE in men with and without ME. The goal was to determine if there is an association between the severity of ME and of IELT. A total of 137 men with lifelong PE were included in this study. Subjects were asked if they had childhood ME. The characteristics and mean IELTs of patients with and without ME were compared using the student's t-test, and the correlation between severity of ME and IELT was assessed with trend test. Of the 137 lifelong PE patients, 57 reported ME. There was a strong negative correlation in patients with ME between the severity of enuresis and IELT, with IELT being shorter in patients with severe ME. A strong correlation between IELT and the severity of ME suggests a common underlying mechanism. Further studies are required to confirm these findings and elucidate the exact pathophysiology.

  13. Segmented polyurethane intravaginal rings for the sustained combined delivery of antiretroviral agents dapivirine and tenofovir.

    Science.gov (United States)

    Johnson, Todd J; Gupta, Kavita M; Fabian, Judit; Albright, Theodore H; Kiser, Patrick F

    2010-02-19

    Dual segment polyurethane intravaginal rings (IVRs) were fabricated to enable sustained release of antiretroviral agents dapivirine and tenofovir to prevent the male to female sexual transmission of the human immunodeficiency virus. Due to the contrasting hydrophilicity of the two drugs, dapivirine and tenofovir were separately formulated into polymers with matching hydrophilicity via solvent casting and hot melt extrusion. The resultant drug loaded rods were then joined together to form dual segment IVRs. Compression testing of the IVRs revealed that they are mechanically comparable to the widely accepted NuvaRing IVR. Physical characterization of the individual IVR segments using wide angle X-ray scattering and differential scanning calorimetry determined that dapivirine and tenofovir are amorphous and crystalline within their polymeric segments, respectively. In vitro release of tenofovir from the dual segment IVR was sustained over 30 days while dapivirine exhibited linear release over the time period. A 90 day accelerated stability study confirmed that dapivirine and tenofovir are stable in the IVR formulation. Altogether, these results suggest that multisegment polyurethane IVRs are an attractive formulation for the sustained vaginal delivery of drugs with contrasting hydrophilicity such as dapivirine and tenofovir. 2009 Elsevier B.V. All rights reserved.

  14. Safety and availability of dapivirine (TMC120) delivered from an intravaginal ring.

    Science.gov (United States)

    Romano, J; Variano, B; Coplan, P; Van Roey, J; Douville, K; Rosenberg, Z; Temmerman, M; Verstraelen, H; Van Bortel, L; Weyers, S; Mitchnick, M

    2009-05-01

    Vaginal delivery of 200 mg or 25 mg dapivirine from intravaginal rings (IVRs) was evaluated over a 7-day period in two phase 1 safety trials (IPM001 and IPM008, respectively) in a total of 25 healthy women 19 to 46 years of age. The IVR was generally safe and well tolerated with similar adverse events observed in the placebo and dapivirine groups. Across both studies, dapivirine concentrations in vaginal fluids measured at the introitus, cervix, and ring area were within the mean range of 0.7-7.1 microg/ml. Mean dapivirine concentrations in vaginal and cervical tissues on day 7 were 0.3-0.7 microg/g in IPM001 and 1.5-3.5 microg/g in IPM008. Mean plasma concentrations of dapivirine were Dapivirine from both IVRs was successfully distributed throughout the lower genital tract at concentrations >1000x the EC(50) against wild-type HIV-1 (LAI) in MT4 cells suggesting that IVR delivery of microbicides is a viable option meriting further study.

  15. Static and dynamic MRI of a urinary control intra-vaginal device

    Energy Technology Data Exchange (ETDEWEB)

    Maubon, A.J. [Department of Medical Imaging, C. M. C. Beausoleil, Montpellier (France); Department of Radiology, CHU Dupuytren, Limoges (France); Boncoeur-Martel, M.P. [Department of Radiology, CHU Dupuytren, Limoges (France); Juhan, V.; Rouanet, J.P. [Department of Medical Imaging, C. M. C. Beausoleil, Montpellier (France); Courtieu, C.R. [Department of Gynecology, C. M. C. Beausoleil, Montpellier (France); Department of Obstetrics and Gynecology, C. H. U., F-30029 Nimes (France); Thurmond, A.S. [Women' s Imaging, Meridian Park Hospital, Portland, OR (United States); Aubas, P. [Department of Medical Information, Hopital Arnaud de Villeneuve, F-34295 Montpellier (France); Mares, P. [Department of Obstetrics and Gynecology, C. H. U., F-30029 Nimes (France)

    2000-06-01

    The aim of this study was to describe by MRI, in dynamic conditions at rest and straining, the anatomical modifications induced by a commercially available intravaginal device (IVD) aimed at relieving female stress urinary incontinence. Ten female patients complaining of stress urinary incontinence (SUI) had pelvic MRI with static and dynamic sequences, without and with a self-inserted IVD. We studied positions and angulations of the IVD in the pelvis. Paired t-test allowed comparisons of: position of the bladder neck; urethral angulation with the pubis axis; position of the urethra; and posterior urethro-vesical angle (PUVA) without and with IVD. At rest, in ten of ten cases IVD laid cranial to the pubo-rectal muscle; with an average angulation of 95 {+-} 10 with the pubis axis, laterally tilted in three of ten cases. In maximum straining with IVD bladder neck descent was lower by an average of 5.2 {+-} 3.1 mm (p = 0.001), pubo-urethral angle opening was smaller by an average of 22 {+-} 20 (p = 0.015), and bladder neck to pubis distance was shorter by an average of 5.7 {+-} 4 mm. Posterior urethro-vesical angle was not significantly modified. Dynamic MRI allowed a non-invasive assessment of the mode of action of an IVD. The main modifications were a support of the bladder base and bladder neck, with a superior displacement of the urethra toward the pubis. (orig.)

  16. Dose calculation in brachytherapy with microcomputers

    International Nuclear Information System (INIS)

    Elbern, A.W.

    1989-01-01

    The computer algorithms, that allow the calculation of brachytherapy doses and its graphic representation for implants, using programs developed for Pc microcomputers are presented. These algorithms allow to localized the sources in space, from their projection in radiographics images and trace isodose counter. (C.G.C.) [pt

  17. Severe rectal complications after prostate brachytherapy

    International Nuclear Information System (INIS)

    Wallner, Kent; Sutlief, Stephen; Bergsagel, Carl; Merrick, Gregory S.

    2015-01-01

    Purpose: Some investigators have reported severe rectal complications after brachytherapy. Due to the low number of such events, their relationship to dosimetric parameters has not been well characterized. Methods and materials: A total of 3126 patients were treated with low dose rate brachytherapy from 1998 through 2010. 2464 had implant alone, and 313 had implant preceded by 44–46 Gy supplemental external beam radiation (EBRT). Post-implant dosimetry was based on a CT scan obtained on the day of implant, generally within 30 min of the procedure. Every patient’s record was reviewed for occurrence of rectal complications. Results: Eight of 2464 patients (0.32%) treated with brachytherapy alone developed a radiation-related rectal fistula. Average prostatic and rectal dose parameters were moderately higher for fistula patients than for patients without a severe rectal complication. For instance, the average R100 was 1.2 ± 0.75 cc for fistula patients, versus 0.37 ± 0.88 cc for non-fistula patients. However, the fistula patients’ values were well within the range of values for patients without a rectal complication. Four patients had some attempt at repair or reconstruction, but long-term functional outcomes were not favorable. Conclusions: Rectal fistulas are a very uncommon potential complication of prostate brachytherapy, which can occur even in the setting of acceptable day 0 rectal doses. Their occurrence is not easily explained by standard dosimetric or clinical factors

  18. Endorectal high dose rate brachytherapy quality assurance

    International Nuclear Information System (INIS)

    Devic, S.; Vuong, T.; Evans, M.; Podgorsak, E.

    2008-01-01

    We describe our quality assurance method for preoperative high dose rate (HDR) brachytherapy of endorectal tumours. Reproduction of the treatment planning dose distribution on a daily basis is crucial for treatment success. Due to the cylindrical symmetry, two types of adjustments are necessary: applicator rotation and dose distribution shift along the applicator axis. (author)

  19. The hazy dawn of brachytherapy

    International Nuclear Information System (INIS)

    Dutreix, J.; Tubiana, M.; Pierquin, B.

    1998-01-01

    The discovery of radium by Pierre and Marie Curie in December 1898 opened a new era in science and within a few years provided medicine with a new means of tumor treatment. Their personal contribution to the start and early development of clinical applications should not be overlooked. The Curies did not limit their support to providing radium sources to medical pioneers but took a deep interest in the horizons of radiumtherapy. Pierre was one of the first to search for and demonstrate a biological effect of radium radiation. He investigated the radioactivity of the waters of hydrotherapeutic resorts. Marie took care of the measurement of the medical sources personally, convinced that the result of the treatment depends on the precise knowledge of the amount of radium applied. Her perseverance resulted in the establishment of the Institut du Radium (1909) in which, besides the physico-chemical laboratory, a biological department was set up. The latter became the Fondation Curie (1920), a leading medical center of treatment and training, with an integrated team of physicists, radiobiologists and clinicians led by Regaud. One hundred years after the discovery of radium, patients benefit today from the extensive clinical experience that has been collected over the years and from sophisticated developments in application techniques, dosimetry and quality assurance; the professional risk has been precisely assessed and the improvements in material and procedure have enabled the medical personnel to work in hazard-free conditions. This outcome results from the continuous progress that the pioneers gave impulse to. This paper intends to recall their efforts and achievements, as well as the difficulties and the problems they encountered during the first 2 decades when the sturdy foundations of brachytherapy were built. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Dosimetric model for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Flower, E.E.; Stroud, D.B.

    2000-01-01

    Full text: Intravascular brachytherapy has been shown to be a prophylaxis for restenosis. Adventitial macrophages, which are extremely radiosensitive, initiate neointima formation. A model of the dose levels of the treatment range is developed, assuming that the adventitia is the target tissue. If the adventitia receives a dose of less than 10 Gy, it is assumed the treatment will be ineffective. If the dose to any part of the wall is above 30 Gy, it is assumed that the treatment could be detrimental. Hence the treatment range is between 10 and 30 Gy, with 20 Gy being the optimum dosage to the adventitia. An algorithm using numerical integration of published dose kernels calculates the dose at any point surrounding a beta ( 32 P) line source of finite length. Dose profiles were obtained to demonstrate edge effects. For long lesions, the source is often stepped along the artery. Dose changes due to separation or overlapping of sources during source stepping procedures were also determined. Isodose curves were superimposed on intravascular ultrasound images to demonstrate dose levels. For an exposure time of 60 seconds with a 200mCi source, the optimum dose of 20 Gy occurs at a distance 1.94mm from the centre of the source. The upper limit of the treatment dose range (30 Gy) occurs at 1.59mm. The lower limit of the treatment dose range (10 Gy) occurs at 2.7mm. Significant perturbations to the treatment dose range can be caused by non-centering of the source, edge effects and separation or overlapping of sources in stepping procedures. Despite these concerns, many successful procedures have been reported and this implies that the model is over simplified and requires modifications. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  1. Calibration of {sup 192}Ir high dose rate brachytherapy sources

    Energy Technology Data Exchange (ETDEWEB)

    Marechal, M H [Instituto de Radioprotecao e Dozimetria, Rio de Jainero (Brazil); Almeida, C.E. de [Laboratorio de Ciencias Radiologicas, UERL, Rio de Janeiro (Brazil); Sibata, C H [Roswell Park Cancer Inst., Buffalo, NY (United States)

    1996-08-01

    A method for calibration of high dose rate sources used in afterloading brachytherapy systems is described. The calibration for {sup 192}Ir is determined by interpolating {sup 60}Co gamma-rays and 250 kV x-rays calibration factors. All measurements were done using the same build up caps as described by Goetsch et al and recommended by AAPM. The attenuation correction factors were determined to be 0.9903, 0.9928 and 0.9993 for {sup 192}Ir, {sup 60}Co and 250 kV x-ray, respectively. A wall + cap thickness of 0.421 g.cm{sup -2} is recommended for all measurements to ensure electronic equilibrium for {sup 60}Co and {sup 192}Ir gamma-ray beams. A mathematical formalism is described for determination of (N{sub x}){sub Ir}. (author). 5 refs, 1 fig.

  2. Prostate brachytherapy in Ghana: our initial experience

    Directory of Open Access Journals (Sweden)

    James Edward Mensah

    2016-10-01

    Full Text Available Purpose: This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. Material and methods : A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. Results: The median patient age was 64.0 years (range 46-78 years. The median follow-up was 58 months (range 18-74 months. Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6% experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2. One patient developed a recto urethral fistula (grade 3 following banding for hemorrhoids. Conclusions : Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively

  3. Automated intraoperative calibration for prostate cancer brachytherapy

    International Nuclear Information System (INIS)

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-01-01

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 ± 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 ± 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 ± 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 ± 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  4. Microdosimetric evaluation of relative biological effectiveness for 103PD, 125I, 241AM, and 192IR brachytherapy sources

    International Nuclear Information System (INIS)

    Wuu, C.S.; Kliauga, P.; Zaider, M.; Amols, H.I.

    1996-01-01

    Purpose: To determine the microdosimetric-derived relative biological effectiveness (RBE) of 103 Pd, 125 I, 241 Am, and 192 Ir brachytherapy sources at low doses and/or low dose rates. Methods and Materials: The Theory of Dual Radiation Action can be used to predict expected RBE values based on the spatial distribution of energy deposition at microscopic levels from these sources. Single-event lineal energy spectra for these isotopes have been obtained both experimentally and theoretically. A grid-defined wall-less proportional counter was used to measure the lineal energy distributions. Unlike conventional Rossi proportional counters, the counter used in these measurements has a conducting nylon fiber as the central collecting anode and has no metal parts. Thus, the Z-dependence of the photoelectric effect is eliminated as a source of measurement error. Single-event spectra for these brachytherapy sources have been also calculated by: (a) the Monte Carlo code MCNP to generate the electron slowing down spectrum, (b) transport of monoenergetic electron tracks, event by event, with our Monte Carlo code DELTA, (c) using the concept of associated volume to obtain the lineal energy distribution f(y) for each monoenergetic electron, and (d) obtaining the composite lineal energy spectrum for a given brachytherapy source based on the electron spectrum calculated at step (a). Results: Relative to 60 Co, the RBE values obtained from this study are: 2.3 for 103 Pd, 2.1 for 125 I, 2.1 for 241 Am, and 1.3 for 192 Ir. Conclusions: These values are consistent with available data from in vitro cell survival experiments. We suggest that, at least for these brachytherapy sources, microdosimetry may be used as a credible alternative to time-consuming (and often uncertain) radiobiological experiments to obtain information on radition quality and make reliable predictions of RBE in low dose rate brachytherapy

  5. Low dose rate Ir-192 interstitial brachytherapy for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Oki, Yosuke; Dokiya, Takushi; Yorozu, Atsunori; Suzuki, Takayuki; Saito, Shiro; Monma, Tetsuo; Ohki, Takahiro [National Tokyo Medical Center (Japan); Murai, Masaru; Kubo, Atsushi

    2000-04-01

    From December 1997 through January 1999, fifteen prostatic cancer patients were treated with low dose rate Ir-192 interstitial brachytherapy using TRUS and perineal template guidance without external radiotherapy. Up to now, as no apparent side effects were found, the safety of this treatment is suggested. In the future, in order to treat prostatic cancer patients with interstitial brachytherapy using I-125 or Pd-103, more investigation for this low dose rate Ir-192 interstitial brachytherapy is needed. (author)

  6. MIV-150-containing intravaginal rings protect macaque vaginal explants against SHIV-RT infection.

    Science.gov (United States)

    Ouattara, Louise A; Barnable, Patrick; Mawson, Paul; Seidor, Samantha; Zydowsky, Thomas M; Kizima, Larisa; Rodriguez, Aixa; Fernández-Romero, José A; Cooney, Michael L; Roberts, Kevin D; Gettie, Agegnehu; Blanchard, James; Robbiani, Melissa; Teleshova, Natalia

    2014-05-01

    Recent studies demonstrated that intravaginal rings (IVRs) containing 100 mg of the nonnucleoside reverse transcriptase inhibitor (NNRTI) MIV-150 significantly protect macaques against a chimeric simian-human immunodeficiency virus that expresses the HIV-1 HxB2 reverse transcriptase (SHIV-RT) when present before and after vaginal challenge. The objectives of this study were to (i) evaluate the pharmacodynamics (PD) of MIV-150 in vaginal fluids (VF) and in ectocervical and vaginal tissues following 100-mg MIV-150 IVR exposure and to (ii) gain more insight whether pharmacokinetics (PK) of MIV-150 can predict PD. MIV-150 in VF collected at 1 day and 14 days post-MIV-150 IVR insertion inhibited ex vivo SHIV-RT infection in vaginal biopsy specimens from untreated animals (not carrying IVRs) in a dose-dependent manner. Previous PK studies demonstrated a significant increase of ectocervical and vaginal tissue MIV-150 concentrations 14 days versus 1 day post-IVR insertion, with the highest increase in vaginal tissue. Therefore, we tested PD of MIV-150 in tissues 14 days post-MIV-150 IVR insertion. Ex vivo SHIV-RT infection of vaginal, but not ectocervical, tissues collected 14 days post-MIV-150 IVR insertion was significantly inhibited compared to infection at the baseline (prior to MIV-150 IVR exposure). No changes in vaginal and ectocervical tissue infection were observed after placebo IVR exposure. Overall, these data underscore the use of the ex vivo macaque explant challenge models to evaluate tissue and VF PK/PD of candidate microbicides before in vivo animal efficacy studies. The data support further development of MIV-150-containing IVRs.

  7. Investigating the feasibility of temperature-controlled accelerated drug release testing for an intravaginal ring.

    Science.gov (United States)

    Externbrink, Anna; Clark, Meredith R; Friend, David R; Klein, Sandra

    2013-11-01

    The objective of the present study was to investigate if temperature can be utilized to accelerate drug release from Nuvaring®, a reservoir type intravaginal ring based on polyethylene vinyl acetate copolymer that releases a constant dose of contraceptive steroids over a duration of 3 weeks. The reciprocating holder apparatus (USP 7) was utilized to determine real-time and accelerated etonogestrel release from ring segments. It was demonstrated that drug release increased with increasing temperature which can be attributed to enhanced drug diffusion. An Arrhenius relationship of the zero-order release constants was established, indicating that temperature is a valid parameter to accelerate drug release from this dosage form and that the release mechanism is maintained under these accelerated test conditions. Accelerated release tests are particularly useful for routine quality control to assist during batch release of extended release formulations that typically release the active over several weeks, months or even years, since they can increase the product shelf life. The accelerated method should therefore be able to discriminate between formulations with different release characteristics that can result from normal manufacturing variance. In the case of Nuvaring®, it is well known that the process parameters during the extrusion process strongly influence the polymeric structure. These changes in the polymeric structure can affect the permeability which, in turn, is reflected in the release properties. Results from this study indicate that changes in the polymeric structure can lead to a different temperature dependence of the release rate, and as a consequence, the accelerated method can become less sensitive to detect changes in the release properties. When the accelerated method is utilized during batch release, it is therefore important to take this possible restriction into account and to evaluate the accelerated method with samples from non

  8. Intravaginal ring delivery of the reverse transcriptase inhibitor TMC 120 as an HIV microbicide.

    Science.gov (United States)

    Woolfson, A David; Malcolm, R Karl; Morrow, Ryan J; Toner, Clare F; McCullagh, Stephen D

    2006-11-15

    TMC 120 (Dapivirine) is a potent non-nucleoside reverse transcriptase inhibitor that is presently being developed as a vaginal HIV microbicide. To date, most vaginal microbicides under clinical investigation have been formulated as single-dose semi-solid gels, designed for application to the vagina before each act of intercourse. However, a clear rationale exists for providing long-term, controlled release of vaginal microbicides in order to afford continuous protection against heterosexually transmitted HIV infection and to improve user compliance. In this study we report on the incorporation of various pharmaceutical excipients into TMC 120 silicone, reservoir-type intravaginal rings (IVRs) in order to modify the controlled release characteristics of the microbicide. The results demonstrate that TMC 120 is released in zero-order fashion from the rings over a 28-day period and that release parameters could be modified by the inclusion of release-modifying excipients in the IVR. The hydrophobic liquid excipient isopropyl myristate had little effect on steady-state daily release rates, but did increase the magnitude and duration of burst release in proportion to excipient loading in the IVR. By comparison, the hydrophobic liquid poly(dimethylsiloxane) had little effect on TMC 120 release parameters. A hydrophilic excipient, lactose, had the surprising effect of decreasing TMC 120 burst release while increasing the apparent steady-state daily release in a concentration-dependent manner. Based on previous cell culture data and vaginal physiology, TMC120 is released from the various ring formulations in amounts potentially capable of maintaining a protective vaginal concentration. It is further predicted that the observed release rates may be maintained for at least a period of 1 year from a single ring device. TMC 120 release profiles and the mechanical properties of rings could be modified by the physicochemical nature of hydrophobic and hydrophilic excipients

  9. A novel intravaginal ring to prevent HIV-1, HSV-2, HPV, and unintended pregnancy.

    Science.gov (United States)

    Ugaonkar, Shweta R; Wesenberg, Asa; Wilk, Jolanta; Seidor, Samantha; Mizenina, Olga; Kizima, Larisa; Rodriguez, Aixa; Zhang, Shimin; Levendosky, Keith; Kenney, Jessica; Aravantinou, Meropi; Derby, Nina; Grasperge, Brooke; Gettie, Agegnehu; Blanchard, James; Kumar, Narender; Roberts, Kevin; Robbiani, Melissa; Fernández-Romero, José A; Zydowsky, Thomas M

    2015-09-10

    Women urgently need a self-initiated, multipurpose prevention technology (MPT) that simultaneously reduces their risk of acquiring HIV-1, HSV-2, and HPV (latter two associated with increased risk of HIV-1 acquisition) and prevents unintended pregnancy. Here, we describe a novel core-matrix intravaginal ring (IVR), the MZCL IVR, which effectively delivered the MZC combination microbicide and a contraceptive. The MZCL IVR contains four active pharmaceutical ingredients (APIs): MIV-150 (targets HIV-1), zinc acetate (ZA; targets HIV-1 and HSV-2), carrageenan (CG; targets HPV and HSV-2), and levonorgestrel (LNG; targets unintended pregnancy). The elastomeric IVR body (matrix) was produced by hot melt extrusion of the non-water swellable elastomer, ethylene vinyl acetate (EVA-28), containing the hydrophobic small molecules, MIV-150 and LNG. The solid hydrophilic core, embedded within the IVR by compression, contained the small molecule ZA and the macromolecule CG. Hydrated ZA/CG from the core was released by diffusion via a pore on the IVR while the MIV-150/LNG diffused from the matrix continuously for 94 days (d) in vitro and up to 28 d (study period) in macaques. The APIs released in vitro and in vivo were active against HIV-1ADA-M, HSV-2, and HPV16 PsV in cell-based assays. Serum LNG was at levels associated with local contraceptive effects. The results demonstrate proof-of-concept of a novel core-matrix IVR for sustained and simultaneous delivery of diverse molecules for the prevention of HIV, HSV-2 and HPV acquisition, as well as unintended pregnancy. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Transport and biodistribution of dendrimers across human fetal membranes: implications for intravaginal administration of dendrimer-drug conjugates.

    Science.gov (United States)

    Menjoge, Anupa R; Navath, Raghavendra S; Asad, Abbas; Kannan, Sujatha; Kim, Chong J; Romero, Roberto; Kannan, Rangaramanujam M

    2010-06-01

    Dendrimers are emerging as promising topical antimicrobial agents, and as targeted nanoscale drug delivery vehicles. Topical intravaginal antimicrobial agents are prescribed to treat the ascending genital infections in pregnant women. The fetal membranes separate the extra-amniotic space and fetus. The purpose of the study is to determine if the dendrimers can be selectively used for local intravaginal application to pregnant women without crossing the membranes into the fetus. In the present study, the transport and permeability of PAMAM (poly (amidoamine)) dendrimers, across human fetal membrane (using a side by side diffusion chamber), and its biodistribution (using immunofluorescence) are evaluated ex-vivo. Transport across human fetal membranes (from the maternal side) was evaluated using Fluorescein (FITC), an established transplacental marker (positive control, size approximately 400 Da) and fluorophore-tagged G(4)-PAMAM dendrimers (approximately 16 kDa). The fluorophore-tagged G(4)-PAMAM dendrimers were synthesized and characterized using (1)H NMR, MALDI TOF MS and HPLC analysis. Transfer was measured across the intact fetal membrane (chorioamnion), and the separated chorion and amnion layers. Over a 5 h period, the dendrimer transport across all the three membranes was less than dendrimer (5.8 x 10(-8) cm(2)/s). The biodistribution showed that the dendrimers were largely present in interstitial spaces in the decidual stromal cells and the chorionic trophoblast cells (in 2.5-4 h) and surprisingly, to a smaller extent internalized in nuclei of trophoblast cells and nuclei and cytoplasm of stromal cells. Passive diffusion and paracellular transport appear to be the major route for dendrimer transport. The overall findings further suggest that entry of drugs conjugated to dendrimers would be restricted across the human fetal membranes when administered topically by intravaginal route, suggesting new ways of selectively delivering therapeutics to the mother

  11. Dosimetric study of surface applicators of HDR brachytherapy GammaMed Plus equipment

    International Nuclear Information System (INIS)

    Reyes-Rivera, E.; Sosa, M.; Reyes, U.; Jesús Bernal-Alvarado, José de; Córdova, T.; Gil-Villegas, A.; Monzón, E.

    2014-01-01

    The cone type surface applicators used in HDR brachytherapy for treatment of small skin lesions are an alternative to be used with both electron beams and orthovoltage X-ray equipment. For a good treatment planning is necessary to know the dose distribution of these applicators, which can be obtained by experimental measurement and Monte Carlo simulation as well. In this study the dose distribution of surface applicators of 3 and 3.5 cm diameter, respectively of HDR brachytherapy GammaMed Plus equipment has been estimated using the Monte Carlo method, MCNP code. The applicators simulated were placed on the surface of a water phantom of 20 × 20 × 20 cm and the dose was calculated at depths from 0 to 3 cm with increments of 0.25 mm. The dose profiles obtained at depth show the expected gradients for surface therapy

  12. Dosimetric study of surface applicators of HDR brachytherapy GammaMed Plus equipment

    Energy Technology Data Exchange (ETDEWEB)

    Reyes-Rivera, E., E-mail: eric-1985@fisica.ugto.mx, E-mail: modesto@fisica.ugto.mx, E-mail: uvaldoreyes@fisica.ugto.mx; Sosa, M., E-mail: eric-1985@fisica.ugto.mx, E-mail: modesto@fisica.ugto.mx, E-mail: uvaldoreyes@fisica.ugto.mx; Reyes, U., E-mail: eric-1985@fisica.ugto.mx, E-mail: modesto@fisica.ugto.mx, E-mail: uvaldoreyes@fisica.ugto.mx; Jesús Bernal-Alvarado, José de, E-mail: bernal@fisica.ugto.mx, E-mail: theo@fisica.ugto.mx, E-mail: gil@fisica.ugto.mx; Córdova, T., E-mail: bernal@fisica.ugto.mx, E-mail: theo@fisica.ugto.mx, E-mail: gil@fisica.ugto.mx; Gil-Villegas, A., E-mail: bernal@fisica.ugto.mx, E-mail: theo@fisica.ugto.mx, E-mail: gil@fisica.ugto.mx [División de Ciencias e Ingenierías, Universidad de Guanajuato, 37150 León, Gto. (Mexico); Monzón, E., E-mail: emonzon@imss.gob.mx [Unidad de Alta Especialidad No.1, Instituto Mexicano del Seguro Social, Léon, Gto. (Mexico)

    2014-11-07

    The cone type surface applicators used in HDR brachytherapy for treatment of small skin lesions are an alternative to be used with both electron beams and orthovoltage X-ray equipment. For a good treatment planning is necessary to know the dose distribution of these applicators, which can be obtained by experimental measurement and Monte Carlo simulation as well. In this study the dose distribution of surface applicators of 3 and 3.5 cm diameter, respectively of HDR brachytherapy GammaMed Plus equipment has been estimated using the Monte Carlo method, MCNP code. The applicators simulated were placed on the surface of a water phantom of 20 × 20 × 20 cm and the dose was calculated at depths from 0 to 3 cm with increments of 0.25 mm. The dose profiles obtained at depth show the expected gradients for surface therapy.

  13. A comparison of complications between ultrasound-guided prostate brachytherapy and open prostate brachytherapy

    International Nuclear Information System (INIS)

    Benoit, Ronald M.; Naslund, Michael J.; Cohen, Jeffrey K.

    2000-01-01

    Purpose: Prostate brachytherapy has reemerged during the 1990s as a treatment for clinically localized prostate cancer. The renewed popularity of prostate brachytherapy is largely due to the use of transrectal ultrasound of the prostate, which allows for more accurate isotope placement within the prostate when compared to the open approach. The present study investigates whether this improved cancer control is at the expense of increased morbidity by comparing the morbidity after transrectal ultrasound-guided prostate brachytherapy to the morbidity after prostate brachytherapy performed via an open approach. Methods and Materials: All men in the Medicare population who underwent prostate brachytherapy in the year 1991 were identified. These men were further stratified into those men who underwent prostate brachytherapy via an open approach and the men who underwent prostate brachytherapy with ultrasound guidance. All subsequent inpatient, outpatient, and physician (Part B) Medicare claims for these men from the years 1991-1993 were then analyzed to determine outcomes. Results: In the year 1991, 2124 men in the Medicare population underwent prostate brachytherapy. An open approach was used in 715 men (33.7%), and ultrasound guidance was used in 1409 men (66.3%). Mean age for both cohorts was 73.7 years with a range of 50.7-92.8 years for the ultrasound group and 60.6-92.1 years for the open group. A surgical procedure for the relief of bladder outlet obstruction was performed in 122 men (8.6%) in the ultrasound group and in 54 men (7.6%) in the open group. An artificial urinary sphincter was placed in 2 men (0.14%) in the ultrasound group and in 2 men (0.28%) in the open group. A penile prosthesis was implanted in 10 men (0.71%) in the ultrasound group and in 4 men (0.56%) in the open group. A diagnosis code for urinary incontinence was carried by 95 men (6.7%) in the ultrasound group and by 45 men (6.3%) in the open group. A diagnosis code for erectile dysfunction

  14. Rectal fistulas after prostate brachytherapy

    International Nuclear Information System (INIS)

    Tran, Audrey; Wallner, Kent; Merrick, Gregory; Seeberger, Jergen M.S.; Armstrong, Julius R.T.T.; Mueller, Amy; Cavanagh, William M.S.; Lin, Daniel; Butler, Wayne

    2005-01-01

    Purpose: To compare the rectal and prostatic radiation doses for a prospective series of 503 patients, 44 of whom developed persistent rectal bleeding, and 2 of whom developed rectal-prostatic fistulas. Methods and Materials: The 503 patients were randomized and treated by implantation with 125 I vs. 103 Pd alone (n = 290) or to 103 Pd with 20 Gy vs. 44 Gy supplemental external beam radiotherapy (n = 213) and treated at the Puget Sound Veterans Affairs Medical Center (n = 227), Schiffler Cancer Center (n 242) or University of Washington (n = 34). Patients were treated between September 1998 and October 2001 and had a minimum of 24 months of follow-up. The patient groups were treated concurrently. Treatment-related morbidity was monitored by mailed questionnaires, using standard American Urological Association and Radiation Therapy Oncology Group criteria, at 1, 3, 6, 12, 18, and 24 months. Patients who reported Grade 1 or greater Radiation Therapy Oncology Group rectal morbidity were interviewed by telephone to clarify details regarding their rectal bleeding. Those who reported persistent bleeding, lasting for >1 month were included as having Grade 2 toxicity. Three of the patients with rectal bleeding required a colostomy, two of whom developed a fistula. No patient was lost to follow-up. The rectal doses were defined as the rectal volume in cubic centimeters that received >50%, 100%, 200%, or 300% of the prescription dose. The rectum was considered as a solid structure defined by the outer wall, without attempting to differentiate the inner wall or contents. Results: Persistent rectal bleeding occurred in 44 of the 502 patients, 32 of whom (73%) underwent confirmatory endoscopy. In univariate analysis, multiple parameters were associated with late rectal bleeding, including all rectal brachytherapy indexes. In multivariate analysis, however, only the rectal volume that received >100% of the dose was significantly predictive of bleeding. Rectal fistulas occurred

  15. Patterns of care for brachytherapy in Europe. Results in Spain.

    Science.gov (United States)

    López Torrecilla, J; Guedea, F; Heeren, G; Nissin, R; Ellison, T; Cottier, B

    2006-05-01

    In 2003 ESTRO began a project whose primary objective, was to make a map in the European area of infrastructures in technology and personnel for brachytherapy. A survey and a web site were elaborated. The survey was sent to the 76 Spanish Radiation Oncology departments in May 2003. By the end of 2003, 66 (86.8%) services had responded, 40 (71.4%) of which had brachytherapy. The services with brachytherapy treated 73.5% of the total patients, an average of 1,199 patients. The mean number of patients treated with brachytherapy by department was 135.5 and the number of applications was 265 annually. The average number of specialists was 7, 4 of them trained in brachytherapy. The average weekly work load of the radiation oncologists, physicists, and technicians was 22.6 h, 13.8 h and 21.0 h, respectively. The mean time dedicated to each patient by radiation oncologists, physicists and technicians was 9.2 h; 6.19 h; 7.2 h, respectively. The total number of afterloaders was 43 (22 HDR, 18 LDR, 3 PDR). The tumours most frequently treated with brachytherapy were gynaecological (56.24%), breast (14.2%) and prostate (11.7%). High dose rate was used in 47.46% of the patients and low dose rate in 47.24%. Between 1997 and 2002 there was an increase of 50.53% in patients treated with brachytherapy. The survey shows the brachytherapy resources and activity in Spain up to 2003. Increased use of brachytherapy in prostate tumours, prevalence of gynaecology brachytherapy and similar number of treatments with HDR and LDR are demonstrated in the Patterns of Care of Brachytherapy in Europe (PCBE) study in Spain.

  16. Comparison of absorbed dose in the cervix carcinoma therapy by brachytherapy of high dose rate using the conventional planning and Monte Carlo simulation

    International Nuclear Information System (INIS)

    Silva, Aneli Oliveira da

    2010-01-01

    This study aims to compare the doses received for patients submitted to brachytherapy High Dose Rate (HDR) brachytherapy, a method of treatment of the cervix carcinoma, performed in the planning system PLATO BPS with the doses obtained by Monte Carlo simulation using the radiation transport code MCNP 5 and one female anthropomorphic phantom based on voxel, the FAX. The implementation of HDR brachytherapy treatment for the cervix carcinoma consists of the insertion of an intrauterine probe and an intravaginal probe (ring or ovoid) and then two radiographs are obtained, anteroposterior (AP) and lateral (LAT) to confirm the position of the applicators in the patient and to allow the treatment planning and the determination of the absorbed dose at points of interest: rectum, bladder, sigmoid and point A, which corresponds anatomically to the crossings of the uterine arteries with ureters The absorbed doses obtained with the code MCNP 5, with the exception of the absorbed dose in the rectum and sigmoid for the simulation considering a point source of 192 Ir, are lower than the absorbed doses from PLATO BPS calculations because the MCNP 5 considers the chemical compositions and densities of FAX body, not considering the medium as water. When considering the Monte Carlo simulation for a source with dimensions equal to that used in the brachytherapy irradiator used in this study, the values of calculated absorbed dose to the bladder, to the rectum, to the right point A and to the left point A were respectively lower than those determined by the treatment planning system in 33.29, 5.01, 22.93 and 19.04%. These values are almost all larger than the maximum acceptable deviation between patient planned and administered doses (5 %). With regard to the rectum and bladder, which are organs that must be protected, the present results are in favor of the radiological protection of patients. The point A, that is on the isodose of 100%, used to tumor treatment, the results indicate

  17. Sexual function after permanent prostate brachytherapy

    International Nuclear Information System (INIS)

    Galbreath, R.W.; Merrick, G.S.; Butler, W.M.; Stipetich, R.L.; Abel, L.J.; Lief, J.H.

    2001-01-01

    Purpose: To determine the incidence of potency preservation following permanent prostate brachytherapy and to evaluate the effect of multiple clinical and treatment parameters on penile erectile function. Materials and Methods: 425 patients underwent permanent prostate brachytherapy from April 1995 to October 1999. 209 patients who were potent prior to brachytherapy and currently not receiving hormonal manipulation were mailed an International Index of Erectile Function (IIEF) questionnaire with a pre-addressed stamped envelope. 180 patients completed and returned the questionnaire. Median patient follow-up was 39 months (range 18-74 months). Pre-implant erectile function was assigned using a three-tiered scoring system (2 = erections always or nearly always sufficient for vaginal penetration; 1 = erections sufficient for vaginal penetration but considered suboptimal; 0 = the inability to obtain erections and/or erections inadequate for vaginal penetration). Post-implant potency was defined as an IIEF score >11. Clinical parameters evaluated for sexual function included patient age, clinical T stage, elapsed time since implantation, hypertension, diabetes mellitus, and tobacco consumption. Evaluated treatment parameters included the utilization of neoadjuvant hormonal manipulation and the choice of isotope. The efficacy of sildenafil citrate in brachytherapy induced erectile dysfunction (ED) was also evaluated. Results: A pre-treatment erectile function score of 2 and 1 were assigned to 126 and 54 patients respectively. With 6 year follow up, 39% of patients maintained potency following prostate brachytherapy with a plateau on the curve. Post-implant preservation of potency (IIEF>11) correlated with pre-implant erectile function (50% versus 14% for pre-implant scores of 2 and 1 respectively, p≤0.0001), patient age (56%, 38%, and 23% for patients <60 years of age, 60-69 years of age, and ≥70 years of age respectively, p=0.012) and a history of diabetes mellitus

  18. The evolution of brachytherapy treatment planning

    International Nuclear Information System (INIS)

    Rivard, Mark J.; Venselaar, Jack L. M.; Beaulieu, Luc

    2009-01-01

    Brachytherapy is a mature treatment modality that has benefited from technological advances. Treatment planning has advanced from simple lookup tables to complex, computer-based dose-calculation algorithms. The current approach is based on the AAPM TG-43 formalism with recent advances in acquiring single-source dose distributions. However, this formalism has clinically relevant limitations for calculating patient dose. Dose-calculation algorithms are being developed based on Monte Carlo methods, collapsed cone, and solving the linear Boltzmann transport equation. In addition to improved dose-calculation tools, planning systems and brachytherapy treatment planning will account for material heterogeneities, scatter conditions, radiobiology, and image guidance. The AAPM, ESTRO, and other professional societies are working to coordinate clinical integration of these advancements. This Vision 20/20 article provides insight into these endeavors.

  19. Radiochromic dye film studies for brachytherapy applications

    International Nuclear Information System (INIS)

    Martinez-Davalos, A.; Rodriguez-Villafuerte, M.; Diaz-Perches, R.; Arzamendi-Perez, S.

    2002-01-01

    Commercial radiochromic dye films have been used in recent years to quantify absorbed dose in several medical applications. In this study we present the characterisation of the GafChromic MD-55-2 dye film, a double sensitive layer film suitable for photon irradiation in brachytherapy applications. Dose measurements were carried out with a low dose rate 137 Cs brachytherapy source, which produces very steep dose gradients in its vicinity, and therefore requires the capability of producing high spatial resolution isodose curves. Quantification of the dose rate in water per unit air kerma strength was obtained using a high-resolution transmission commercial scanner (Agfa DuoScan T1200) with the capability of digitising up to 600 x 1200 pixels per inch using 36 bits per pixel, together with optical density measurements. The Monte Carlo calculations and experimental measurements compared well in the 0-50 Gy dose interval used in this study. (author)

  20. Optimum plastic scintillator and optical fiber combination for brachytherapy dosimetry

    International Nuclear Information System (INIS)

    Arnfield, Mark R.; Gaballa, Hani E.; Zwicker, Robert D.; Islam, Quazi; Schmidt-Ullrich, Rupert

    1995-01-01

    Purpose/Objective: There have been several recent reports using plastic scintillators to measure dose in photon and electron beams. External beam measurements agreed well with standard ion chamber dosimetry. This was implemented by using two identical, parallel optical fibers with a small piece of plastic scintillator attached to one. We have constructed a similar device for application to brachytherapy. Brachytherapy dosimetry is a more difficult problem than external beam because of high dose gradients and widely ranging photon energies. Based on detailed spectral measurements, we have designed a dosimeter specifically to meet the unique, stringent needs of brachytherapy. Materials and Methods: The work consisted of two stages. In the first stage, we measured the optical spectra emitted by commercial plastic scintillators and silica core optical fibers in the presence of a 10 Curie iridium 192 HDR source. In the second stage, the spectral information was used to select an optimum combination of scintillator and fiber which were incorporated in the dosimeter. Equipment for the spectral measurements included a 0.1 meter monochromator with a sensitive photomultiplier (PMT) with flat response across the visible. The resolution of spectral scans was 4 nm. The dosimeter was constructed with a 1mm x 3mm piece of plastic scintillator bonded with optical cement to a 0.6 mm diameter silica core optical fiber. A second, identical optical fiber running alongside the first, with no scintillator attached, was used for background subtraction. Two PMTs with high sensitivity in the visible were used at the fiber distal ends. There was a space for an optical filter between the fiber and the PMTs, whose purpose is described below. The PMTs were connected to a differential pair whose output was transferred to a current source for measurement by a standard electrometer. Results: The scintillation spectra of six different types of silica core optical fibers in the presence of the

  1. Qualitative and quantitative analysis of bacteria from vaginitis associated with intravaginal implants in ewes following estrus synchronization

    Directory of Open Access Journals (Sweden)

    Carlos Otávio de Paula Vasconcelos

    2016-04-01

    Full Text Available ABSTRACT: This study evaluated the presence of vaginitis and the bacterial load associated with different intravaginal implants in ewes. Twenty-four Dorper and crossbred ewes were allocated into three groups and received intravaginal implant containing 0.3g progesterone (CIDR(r, 60mg MAP or sponges without progesterone (CONTROL for six days. Then, CIDR and MAP treated-ewes received 12.5mg dinoprost and 300IU eCG. Vaginal mucus samples were collected at four times: before device insertion, at the day of its removal, 24 and 48 hours after. The samples were cultured and the colonies were counted (CFU/mL and identified. The results obtained from the counting of CFU mL-1 were submitted to Kruskal-Wallis H test, with P0.05 in comparison with MAP and CIDR-treated ewes. During the occurrence of vaginitis, the predominant isolates belonged to the coliform group, mainly Escherichia coli (72.7%. Such infection was not determined by the members of the vaginal microbiota that were present before implant insertion and normal microbiota was restored between 24 to 48 hours after insert removal.

  2. Brachytherapy needle deflection evaluation and correction

    International Nuclear Information System (INIS)

    Wan Gang; Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2005-01-01

    In prostate brachytherapy, an 18-gauge needle is used to implant radioactive seeds. This thin needle can be deflected from the preplanned trajectory in the prostate, potentially resulting in a suboptimum dose pattern and at times requiring repeated needle insertion to achieve optimal dosimetry. In this paper, we report on the evaluation of brachytherapy needle deflection and bending in test phantoms and two approaches to overcome the problem. First we tested the relationship between needle deflection and insertion depth as well as whether needle bending occurred. Targeting accuracy was tested by inserting a brachytherapy needle to target 16 points in chicken tissue phantoms. By implanting dummy seeds into chicken tissue phantoms under 3D ultrasound guidance, the overall accuracy of seed implantation was determined. We evaluated methods to overcome brachytherapy needle deflection with three different insertion methods: constant orientation, constant rotation, and orientation reversal at half of the insertion depth. Our results showed that needle deflection is linear with needle insertion depth, and that no noticeable bending occurs with needle insertion into the tissue and agar phantoms. A 3D principal component analysis was performed to obtain the population distribution of needle tip and seed position relative to the target positions. Our results showed that with the constant orientation insertion method, the mean needle targeting error was 2.8 mm and the mean seed implantation error was 2.9 mm. Using the constant rotation and orientation reversal at half insertion depth methods, the deflection error was reduced. The mean needle targeting errors were 0.8 and 1.2 mm for the constant rotation and orientation reversal methods, respectively, and the seed implantation errors were 0.9 and 1.5 mm for constant rotation insertion and orientation reversal methods, respectively

  3. Erectile Function Durability Following Permanent Prostate Brachytherapy

    International Nuclear Information System (INIS)

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H.

    2009-01-01

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 ≥ 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  4. Design and optimization of a brachytherapy robot

    Science.gov (United States)

    Meltsner, Michael A.

    Trans-rectal ultrasound guided (TRUS) low dose rate (LDR) interstitial brachytherapy has become a popular procedure for the treatment of prostate cancer, the most common type of non-skin cancer among men. The current TRUS technique of LDR implantation may result in less than ideal coverage of the tumor with increased risk of negative response such as rectal toxicity and urinary retention. This technique is limited by the skill of the physician performing the implant, the accuracy of needle localization, and the inherent weaknesses of the procedure itself. The treatment may require 100 or more sources and 25 needles, compounding the inaccuracy of the needle localization procedure. A robot designed for prostate brachytherapy may increase the accuracy of needle placement while minimizing the effect of physician technique in the TRUS procedure. Furthermore, a robot may improve associated toxicities by utilizing angled insertions and freeing implantations from constraints applied by the 0.5 cm-spaced template used in the TRUS method. Within our group, Lin et al. have designed a new type of LDR source. The "directional" source is a seed designed to be partially shielded. Thus, a directional, or anisotropic, source does not emit radiation in all directions. The source can be oriented to irradiate cancerous tissues while sparing normal ones. This type of source necessitates a new, highly accurate method for localization in 6 degrees of freedom. A robot is the best way to accomplish this task accurately. The following presentation of work describes the invention and optimization of a new prostate brachytherapy robot that fulfills these goals. Furthermore, some research has been dedicated to the use of the robot to perform needle insertion tasks (brachytherapy, biopsy, RF ablation, etc.) in nearly any other soft tissue in the body. This can be accomplished with the robot combined with automatic, magnetic tracking.

  5. Procedures for calibration of brachytherapy sources

    International Nuclear Information System (INIS)

    Alfonso Laguardia, R.; Alonso Samper, J.L.; Morales Lopez, J.L.; Saez Nunez, D.G.

    1997-01-01

    Brachytherapy source strength verification is a responsibility of the user of these source, in fact of the Medical Physicists in charge of this issue in a Radiotherapy Service. The calibration procedures in the users conditions are shown. Specifics methods for source strength determination are recommended, both for High Dose Rate (HDR) sources with Remote Afterloading equipment and for Low Dose Rate sources. The The results of the calibration of HDR Remote After loaders are indicated

  6. Turkish validation of the premature ejaculation diagnostic tool and its association with intravaginal ejaculatory latency time.

    Science.gov (United States)

    Serefoglu, E C; Cimen, H I; Ozdemir, A T; Symonds, T; Berktas, M; Balbay, M D

    2009-01-01

    There are uncertain issues on the diagnostic methods of premature ejaculation (PE). The premature ejaculation diagnostic tool (PEDT) was developed to systematically apply the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria in diagnosing PE and the aim of this study is to carry out the Turkish validation of the PEDT and to evaluate its association with intravaginal ejaculatory latency time (IELT). A total of 94 patients with a self-reported complaint of PE and 88 men without PE were enrolled into the study and requested to complete the nine-item PEDT, which was translated into Turkish. The patients were also requested to measure IELT. All participants were requested to come for a second visit to assess the PEDT's retest reliability; data from 78 men in the PE group and 69 men in the control group were collected. The IELT data of 35 patients were also recorded. The mean age of the PE group and the control group were 39.4+/-9.7 (24-65) and 30.1+/-5.7 (20-56), respectively, (P=0.068). Among the patients in the PE group, 24 (68.5%) reported life-long PE, whereas 11 (31.5%) reported acquired PE. The geometric mean IELT of the PE group was 59.7+/-46.2 (6.5-197.7) s. The number of men reporting IELTs of 2 min were 20 (57.1%), 11 (31.5) and 4 (11.4%), respectively. The factor analysis assessment showed that the five-item combination (questions 1, 2, 3, 4 and 8) explained 74.4% of the variance, there were no other combinations that explained the variance more effectively. Cronbach's alpha score of five-item combination was calculated as 0.77, showing adequate internal consistency. The overall Cronbach's alpha score did not increase if any item combination was deleted. The test-retest correlation coefficients of each item were higher than 0.80 and the correlation coefficient of the total score was 0.90. The PEDT and IELT showed an adequate correlation (rho=0.44). As a conclusion, the validated five-item Turkish version of PEDT is a

  7. Radioimmunoassay of serum d-Norgestrel in women following oral and intravaginal administration

    International Nuclear Information System (INIS)

    Stanczyk, F.Z.; Hiroi, M.; Goebelsmann, U.; Brenner, P.F.; Lumkin, M.E.; Mishell, D.R. Jr.

    1975-01-01

    A radioimmunoassay (RIA) method for measuring d-Norgestrel (d-Ng) in serum has been developed utilizing petroleum ether extraction, an antiserum raised against d-Norgestrel-3-(0-carboxymethyl) oxime-epsilon-aminocaproic acid--boxine serum albumin, d-Norgestrel-3-(0-carboxymethyl) imino-[ 125 I]-iodohistamine, and dextran-coated charcoal separation. Control serum blanks were undetectable, 6 pg of d-Ng was measurable in 0.1 ml of serum with a high reliability, and intra- and interassay coefficients of variation were 4.4 and 4.9 percent, respectively. d-Ng added to control serum was quantitatively recovered. This RIA proved to be highly specific for d-Ng, cross-reacting less than 0.01 percent with 1-Ng and some 4 to 8 percent with 5α- and 5β-tetrahydro-d-Ng. Serum d-Ng levels measured in 3 women after ingestion of 75 μg of dl-Ng rose to 1.5 to 2 ng/ml within 1/2 to 2-3 hours after oral intake and fell rapidly thereafter to 0.2 to 0.4 ng/ml within 24 hours. Insertion of Silastic intravaginal rings (IVRs), containing 50 or 100 mg of dl-Ng, into 3 women for periods of 3 weeks resulted in a rapid rise of serum d-Ng after insertion. Serum d-Ng levels were highest 24 to 48 hours after the first insertion of each IVR, reaching peak levels of about 5 and 7 to 11 ng/ml, respectively, and declined gradually during the ensuing 15 to 20 days to some 30 to 40 percent of the peak serum d-Ng concentration. Serum d-Ng levels attained after IVR reinsertion remained relatively constant at 1 to 3 ng/ml during each subsequent cycle in all subjects and fell rapidly after each IVR removal. Serum estradiol and progesterone concentrations, measured about 3 times a week in these patients, indicated that ovulation was consistently inhibited

  8. Intravaginal rings as delivery systems for microbicides and multipurpose prevention technologies

    Directory of Open Access Journals (Sweden)

    Thurman AR

    2013-10-01

    Full Text Available Andrea Ries Thurman, Meredith R Clark, Jennifer Hurlburt, Gustavo F Doncel CONRAD, Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, VA, USA Abstract: There is a renewed interest in delivering pharmaceutical products via intravaginal rings (IVRs. IVRs are flexible torus-shaped drug delivery systems that can be easily inserted and removed by the woman and that provide both sustained and controlled drug release, lasting for several weeks to several months. In terms of women's health care products, it has been established that IVRs effectively deliver contraceptive steroids and steroids for the treatment of postmenopausal vaginal atrophy. A novel application for IVRs is the delivery of antiretroviral drugs for the prevention of human immunodeficiency virus (HIV genital infection. Microbicides are antiviral drugs delivered topically for HIV prevention. Recent reviews of microbicide IVRs have focused on technologies in development and optimizing ring design. IVRs have several advantages, including the ability to deliver sustained drug doses for long periods of time while bypassing first pass metabolism in the gut. IVRs are discreet, woman-controlled, and do not require a trained provider for placement or fitting. Previous data support that women and their male sexual partners find IVRs highly acceptable. Multipurpose prevention technology (MPT products provide protection against unintended/mistimed pregnancy and reproductive tract infections, including HIV. Several MPT IVRs are currently in development. Early clinical testing of new microbicide and MPT IVRs will require a focus on safety, pharmacokinetics and pharmacodynamics. Specifically, IVRs will have to deliver tissue concentrations of drugs that are pharmacodynamically active, do not cause mucosal alterations or inflammation, and do not change the resident microbiota. The emergence of resistance to antiretrovirals will need to be investigated. IVRs should not

  9. Dosimetry in high dose rate endoluminal brachytherapy

    International Nuclear Information System (INIS)

    Uno, Takashi; Kotaka, Kikuo; Itami, Jun

    1994-01-01

    In endoluminal brachytherapy for the tracheobronchial tree, esophagus, and bile duct, a reference point for dose calculation has been often settled at 1 cm outside from the middle of source travel path. In the current study, a change in the ratio of the reference point dose on the convex to concave side (Dq/Dp) was calculated, provided the source travel path bends as is the case in most endoluminal brachytherapies. Point source was presumed to move stepwise at 1 cm interval from 4 to 13 locations. Retention time at each location was calculated by personal computer so as to deliver equal dose at 1 cm from the linear travel path. With the retention time remaining constant, the change of Dq/Dp was assessed by bending the source travel path. Results indicated that the length of the source travel path and radius of its curve influenced the pattern of change in Dq/Dp. Therefore, it was concluded that the difference in reference dose on the convex and concave side of the curved path is not negligible under certain conditions in endoluminal brachytherapy. In order to maintain the ratio more than 0.9, relatively greater radius was required when the source travel path was decreased. (author)

  10. Radioactive seed immobilization techniques for interstitial brachytherapy

    International Nuclear Information System (INIS)

    Yan, K.; Podder, T.; Buzurovic, I.; Hu, Y.; Dicker, A.; Valicenti, R.; Yu, Y.; Messing, E.; Rubens, D.; Sarkar, N.; Ng, W.

    2008-01-01

    In prostate brachytherapy, seeds can detach from their deposited sites and move locally in the pelvis or migrate to distant sites including the pulmonary and cardiac regions. Undesirable consequences of seed migration include inadequate dose coverage of the prostate and tissue irradiation effects at the site of migration. Thus, it is clinically important to develop seed immobilization techniques. We first analyze the possible causes for seed movement, and propose three potential techniques for seed immobilization: (1) surgical glue, (2) laser coagulation and (3) diathermy coagulation. The feasibility of each method is explored. Experiments were carried out using fresh bovine livers to investigate the efficacy of seed immobilization using surgical glue. Results have shown that the surgical glue can effectively immobilize the seeds. Evaluation of the radiation dose distribution revealed that the non-immobilized seed movement would change the planned isodose distribution considerably; while by using surgical glue method to immobilize the seeds, the changes were negligible. Prostate brachytherapy seed immobilization is necessary and three alternative mechanisms are promising for addressing this issue. Experiments for exploring the efficacy of the other two proposed methods are ongoing. Devices compatible with the brachytherapy procedure will be designed in future. (orig.)

  11. A fibre optic dosimeter customised for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Suchowerska, N. [Department of Radiation Oncology, Royal Prince Alfred Hospital, Camperdown, NSW 2050 (Australia); School of Physics, University of Sydney, NSW 2006 (Australia)], E-mail: Natalka@email.cs.nsw.gov.au; Lambert, J.; Nakano, T. [Department of Radiation Oncology, Royal Prince Alfred Hospital, Camperdown, NSW 2050 (Australia); School of Physics, University of Sydney, NSW 2006 (Australia); Law, S. [School of Physics, University of Sydney, NSW 2006 (Australia); Optical Fibre Technology Centre, University of Sydney, 206 National Innovation Centre, Australian Technology Park, Eveleigh, NSW 1430 (Australia); Elsey, J. [Bandwidth Foundry Pty Ltd, Australian Technology Park, NSW, 1430 (Australia); McKenzie, D.R. [School of Physics, University of Sydney, NSW 2006 (Australia)

    2007-04-15

    In-vivo dosimetry for brachytherapy cancer treatment requires a small dosimeter with a real time readout capability that can be inserted into the patient to determine the dose to critical organs. Fibre optic scintillation dosimeters, consisting of a plastic scintillator coupled to an optical fibre, are a promising dosimeter for this application. We have implemented specific design features to optimise the performance of the dosimeter for specific in-vivo dosimetry during brachytherapy. Two sizes of the BrachyFOD{sup TM} scintillation dosimeter have been developed, with external diameters of approximately 2 and 1 mm. We have determined their important dosimetric characteristics (depth dose relation, angular dependence, energy dependence). We have shown that the background signal created by Cerenkov and fibre fluorescence does not significantly affect the performance in most clinical geometries. The dosimeter design enables readout at less than 0.5 s intervals. The clinical demands of real time in-vivo brachytherapy dosimetry can uniquely be satisfied by the BrachyFOD{sup TM}.

  12. Permanent Prostate Brachytherapy in Prostate Glands 3

    International Nuclear Information System (INIS)

    Mayadev, Jyoti; Merrick, Gregory S.; Reed, Joshua R.; Butler, Wayne M.; Galbreath, Robert W.; Allen, Zachariah A.; Wallner, Kent E.

    2010-01-01

    Purpose: To investigate the dosimetry, treatment-related morbidity, and biochemical outcomes for brachytherapy in patients with prostate glands 3 . Methods and Materials: From November 1996 to October 2006, 104 patients with prostate glands 3 underwent brachytherapy. Multiple prostate, urethral, and rectal dosimetric parameters were evaluated. Treatment-related urinary and rectal morbidity were assessed from patient questionnaires. Cause-specific survival, biochemical progression-free survival, and overall survival were recorded. Results: The median patient age, follow up, and pre-treatment ultrasound volume was 64 years, 5.0 years and 17.6cm 3 , respectively. Median day 0 dosimetry was significant for the following: V100 98.5%, D90 126.1% and R100 <0.5% of prescription dose. The mean urethral and maximum urethral doses were 119.6% and 133.8% of prescription. The median time to International Prostate Symptom Score resolution was 4 months. There were no RTOG grade III or IV rectal complications. The cause-specific survival, biochemical progression-free survival, and overall survival rates were 100%, 92.5%, and 77.8% at 9 years. For biochemically disease-free patients, the median most recent postbrachytherapy PSA value was 0.02 ng/mL. Conclusion: Our results demonstrate that brachytherapy for small prostate glands is highly effective, with an acceptable morbidity profile, excellent postimplant dosimetry, acceptable treatment-related morbidity, and favorable biochemical outcomes.

  13. Brachytherapy treatment with high dose rate

    International Nuclear Information System (INIS)

    Santana Rodriguez, Sergio Marcelino; Rodriguez Rodriguez, Lissi Lisbet; Ciscal Chiclana, Onelio Alberto

    2009-01-01

    Retrospectively analyze results and prognostic factors of cervical cancer patients treated with radio concomitant cisplatin-based chemotherapy, radiation therapy combined modality. Methods: From January 2003 to December 2007, 198 patients with invasive cervical cancer were treated at the Oncology Department of Hospital Robau Celestino Hernandez (brachytherapy performed at INOR). The most common age group was 31 to 40 years. The histology in squamous cell carcinoma accounted for 84.3% of cases. The treatment consisted of external pelvic irradiation and vaginal brachytherapy, high dose rate. Concomitant chemotherapy consisted of cisplatin 40 mg/m2 weekly with a maximum of 70 mg for 5 weeks. Results: 66.2% of patients completed 5 cycles of chemotherapy. The median overall survival was 39 months, overall survival, disease-free survival and survival free of locoregional recurrence at 5 years of 78%, 76% and 78.6% respectively .. We found that clinical stage, histological type (adenocarcinoma worst outcome) were statistically related to level of response. Conclusions: Treatment with external pelvic radiation, brachytherapy and concurrent weekly cisplatin in patients with stage IIIB cervical cancer is feasible in the Chilean public health system, well tolerated and results comparable to international literature. (Author)

  14. In vivo evaluation of a mucoadhesive polymeric caplet for intravaginal anti-HIV-1 delivery and development of a molecular mechanistic model for thermochemical characterization.

    Science.gov (United States)

    Ndesendo, Valence M K; Choonara, Yahya E; Meyer, Leith C R; Kumar, Pradeep; Tomar, Lomas K; Tyagi, Charu; du Toit, Lisa C; Pillay, Viness

    2015-01-01

    The aim of this study was to develop, characterize and evaluate a mucoadhesive caplet resulting from a polymeric blend (polymeric caplet) for intravaginal anti-HIV-1 delivery. Poly(lactic-co-glycolic) acid, ethylcellulose, poly(vinylalcohol), polyacrylic acid and modified polyamide 6, 10 polymers were blended and compressed to a caplet-shaped device, with and without two model drugs 3'-azido-3'-deoxythymidine (AZT) and polystyrene sulfonate (PSS). Thermal analysis, infrared spectroscopy and microscopic analysis were carried out on the caplets employing temperature-modulated DSC (TMDSC), Fourier transform infra-red (FTIR) spectrometer and scanning electron microscope, respectively. In vitro and in vivo drug release analyses as well as the histopathological toxicity studies were carried out on the drug-loaded caplets. Furthermore, molecular mechanics (MM) simulations were carried out on the drug-loaded caplets to corroborate the experimental findings. There was a big deviation between the Tg of the polymeric caplet from the Tg's of the constituent polymers indicating a strong interaction between constituent polymers. FTIR spectroscopy confirmed the presence of specific ionic and non-ionic interactions within the caplet. A controlled near zero-order drug release was obtained for AZT (20 d) and PSS (28 d). In vivo results, i.e. the drug concentration in plasma ranged between 0.012-0.332 mg/mL and 0.009-0.256 mg/mL for AZT and PSS over 1-28 d. The obtained results, which were corroborated by MM simulations, attested that the developed system has the potential for effective delivery of anti-HIV-agents.

  15. Image based brachytherapy planning with special reference to gynaecological cancers

    International Nuclear Information System (INIS)

    Kirisits, C.

    2008-01-01

    Cervical cancer is the most common cancer among women in India and one of the most frequent malignancies in Europe and in North America. In addition endometrium, vagina and vulva cancer are treated with brachytherapy. Especially for locally advanced cervix cancer the integration of image based brachytherapy planning into clinical routine is becoming a new standard for the future

  16. A robotic device for MRI-guided prostate brachytherapy

    NARCIS (Netherlands)

    Lagerburg, V.

    2008-01-01

    One of the treatment options for prostate cancer is brachytherapy with iodine-125 sources. In prostate brachytherapy a high radiation dose is delivered to the prostate with a steep dose fall off to critical surrounding organs. The implantation of the iodine sources is currently performed under

  17. Modeling a Hypothetical 170Tm Source for Brachytherapy Applications

    International Nuclear Information System (INIS)

    Enger, Shirin A.; D'Amours, Michel; Beaulieu, Luc

    2011-01-01

    Purpose: To perform absorbed dose calculations based on Monte Carlo simulations for a hypothetical 170 Tm source and to investigate the influence of encapsulating material on the energy spectrum of the emitted electrons and photons. Methods: GEANT4 Monte Carlo code version 9.2 patch 2 was used to simulate the decay process of 170 Tm and to calculate the absorbed dose distribution using the GEANT4 Penelope physics models. A hypothetical 170 Tm source based on the Flexisource brachytherapy design with the active core set as a pure thulium cylinder (length 3.5 mm and diameter 0.6 mm) and different cylindrical source encapsulations (length 5 mm and thickness 0.125 mm) constructed of titanium, stainless-steel, gold, or platinum were simulated. The radial dose function for the line source approximation was calculated following the TG-43U1 formalism for the stainless-steel encapsulation. Results: For the titanium and stainless-steel encapsulation, 94% of the total bremsstrahlung is produced inside the core, 4.8 and 5.5% in titanium and stainless-steel capsules, respectively, and less than 1% in water. For the gold capsule, 85% is produced inside the core, 14.2% inside the gold capsule, and a negligible amount ( 170 Tm source is primarily a bremsstrahlung source, with the majority of bremsstrahlung photons being generated in the source core and experiencing little attenuation in the source encapsulation. Electrons are efficiently absorbed by the gold and platinum encapsulations. However, for the stainless-steel capsule (or other lower Z encapsulations) electrons will escape. The dose from these electrons is dominant over the photon dose in the first few millimeter but is not taken into account by current standard treatment planning systems. The total energy spectrum of photons emerging from the source depends on the encapsulation composition and results in mean photon energies well above 100 keV. This is higher than the main gamma-ray energy peak at 84 keV. Based on our

  18. Brachytherapy in the treatment of cervical cancer: a review

    Directory of Open Access Journals (Sweden)

    Banerjee R

    2014-05-01

    Full Text Available Robyn Banerjee,1 Mitchell Kamrava21Department of Radiation Oncology, Tom Baker Cancer Centre, Calgary, Alberta, Canada; 2Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USAAbstract: Dramatic advances have been made in brachytherapy for cervical cancer. Radiation treatment planning has evolved from two-dimensional to three-dimensional, incorporating magnetic resonance imaging and/or computed tomography into the treatment paradigm. This allows for better delineation and coverage of the tumor, as well as improved avoidance of surrounding organs. Consequently, advanced brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with historic approaches. This review provides an overview of state-of-the-art gynecologic brachytherapy, with a focus on recent advances and their implications for women with cervical cancer.Keywords: cervical cancer, brachytherapy, image-guided brachytherapy

  19. Radiation Exposure Reduction to Brachytherapy Staff By Using Remote Afterloading

    International Nuclear Information System (INIS)

    Attalla, E.M.

    2005-01-01

    The radiation exposures to the personnel staff from patients with brachytherapy implants in a brachytherapy service were reviewed. Exposures to the brachytherapy personnel, as determined by Thermoluminescence Dosimeter (TLD) monitors, indicates a four-fold reduction in exposures after the implantation of the use of remote afterloading devices. Quarterly TLD monitor data for seven quarters prior to the use of remote afterloading devices demonstrate an average projected annual dose equivalent to the brachytherapy staff of 2543 Μ Sv. After the implantation of the remote afterloading devices, the quarterly TLD monitor data indicate an average dose equivalent per person of 153 Μ Sv. This is 76% reduction in exposure to brachytherapy personnel with the use of these devices

  20. Accelerated partial breast irradiation utilizing balloon brachytherapy techniques

    International Nuclear Information System (INIS)

    Strauss, Jonathan B.; Dickler, Adam

    2009-01-01

    To overcome the barriers to BCT, methods of PBI in the setting of breast conservation have been explored. The method of PBI with the longest published follow-up is multi-catheter interstitial brachytherapy. Balloon-based brachytherapy with the MammoSite brachytherapy applicator was designed to simplify the brachytherapy procedure for PBI, enhance the reproducibility of the dosimetry, and improve patient comfort. The rates of local recurrence following PBI with the MammoSite applicator have been low, but there are few published reports and follow-up has been relatively short. The cosmetic outcomes and toxicity of MammoSite PBI are comparable to those seen after multicatheter-based PBI. Additional methods of balloon brachytherapy, including Xoft and SenoRx Contura have been developed. Finally, long-term follow-up after PBI is important for the welfare of individual patients and in order to establish the efficacy, late toxicity and cosmetic outcomes of this technique.

  1. Brachytherapy in the treatment of head and neck cancer

    International Nuclear Information System (INIS)

    Yoo, Seong Yul

    1999-01-01

    Brachytherapy has been proved to be an effective method for the purpose of increasing radiation dose to the tumor and reducing the dose to the surrounding normal tissue. In head and neck cancer, the rationale of brachytherapy is as follows; Firstly, early small lesion is radiocurative and the major cause of failure is local recurrence. Secondly, it can diminish evidently the dose to the normal tissue especially masseteric muscle and salivary gland. Thirdly, the anatomy of head and neck is suitable to various technique of brachytherapy. On background of accumulated experience of LDR iridium brachytherapy of head and neck cancer for the last 15 years, the author reviewed the history of radioisotope therapy, the characteristics of radionuclides, and some important things in the method, clinical technique and treatment planning. The author analyzed the clinical result of 185 cases of head and neck cancer treated in the Korea Cancer Center Hospital. Finally the future prospect of brachytherapy of head and neck cancer is discussed

  2. Directional interstitial brachytherapy from simulation to application

    Science.gov (United States)

    Lin, Liyong

    Organs at risk (OAR) are sometimes adjacent to or embedded in or overlap with the clinical target volume (CTV) to be treated. The purpose of this PhD study is to develop directionally low energy gamma-emitting interstitial brachytherapy sources. These sources can be applied between OAR to selectively reduce hot spots in the OARs and normal tissues. The reduction of dose over undesired regions can expand patient eligibility or reduce toxicities for the treatment by conventional interstitial brachytherapy. This study covers the development of a directional source from design optimization to construction of the first prototype source. The Monte Carlo code MCNP was used to simulate the radiation transport for the designs of directional sources. We have made a special construction kit to assemble radioactive and gold-shield components precisely into D-shaped titanium containers of the first directional source. Directional sources have a similar dose distribution as conventional sources on the treated side but greatly reduced dose on the shielded side, with a sharp dose gradient between them. A three-dimensional dose deposition kernel for the 125I directional source has been calculated. Treatment plans can use both directional and conventional 125I sources at the same source strength for low-dose-rate (LDR) implants to optimize the dose distributions. For prostate tumors, directional 125I LDR brachytherapy can potentially reduce genitourinary and gastrointestinal toxicities and improve potency preservation for low risk patients. The combination of better dose distribution of directional implants and better therapeutic ratio between tumor response and late reactions enables a novel temporary LDR treatment, as opposed to permanent or high-dose-rate (HDR) brachytherapy for the intermediate risk T2b and high risk T2c tumors. Supplemental external-beam treatments can be shortened with a better brachytherapy boost for T3 tumors. In conclusion, we have successfully finished the

  3. Penile brachytherapy: Results for 49 patients

    International Nuclear Information System (INIS)

    Crook, Juanita M.; Jezioranski, John; Grimard, Laval; Esche, Bernd; Pond, G.

    2005-01-01

    Purpose: To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. Methods and Materials: From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Results: Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact

  4. The 5-HT₁A receptor CG polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy K. C.; van Schaik, R.; Zwinderman, Aeilko H.; Olivier, Berend; Waldinger, Marcel D.

    2014-01-01

    Lifelong premature ejaculation (LPE) is characterized by persistent intravaginal ejaculation latency times (IELTs) of less than 1 min, and has been postulated as a neurobiological dysfunction related to diminished serotonergic neurotransmission with 5-HT₁A receptor hyperfunction and 5-HT₂C

  5. The 5-HT2C receptor gene Cys23Ser polymorphism influences the intravaginal ejaculation latency time in Dutch Caucasian men with lifelong premature ejaculation

    NARCIS (Netherlands)

    Janssen, Paddy Kc; Schaik, Ron van; Olivier, Berend|info:eu-repo/dai/nl/073067199; Waldinger, Marcel D|info:eu-repo/dai/nl/163958564

    2014-01-01

    It has been postulated that the persistent short intravaginal ejaculation latency time (IELT) of men with lifelong premature ejaculation (LPE) is related to 5-hydroxytryptamine (HT)2C receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2C receptor gene

  6. Randomized, Placebo-Controlled Phase 2 Trial of a Lactobacillus crispatus Probiotic Given Intravaginally for Prevention of Recurrent Urinary Tract Infection

    OpenAIRE

    Stapleton, Ann E.; Au-Yeung, Melissa; Hooton, Thomas M.; Fredricks, David N.; Roberts, Pacita L.; Czaja, Christopher A.; Yarova-Yarovaya, Yuliya; Fiedler, Tina; Cox, Marsha; Stamm, Walter E.

    2011-01-01

    In a double-blind placebo-controlled trial of a Lactobacillus crispatus intravaginal suppository probiotic (LACTIN-VÜ, Osel, Inc.) for prevention of recurrent UTI (rUTI) in pre-menopausal women, LACTIN-V was safe, well tolerated, and associated with a reduction in rUTI.

  7. Erectile function after permanent prostate brachytherapy

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Stipetich, Robin L.; Abel, Laurie J.; Lief, Jonathan H.

    2002-01-01

    Purpose: To determine the incidence of potency preservation after permanent prostate brachytherapy using a validated patient-administered questionnaire and to evaluate the effect of multiple clinical and treatment parameters on penile erectile function. Methods and Materials: Four hundred twenty-five patients underwent permanent prostate brachytherapy from April 1995 to October 1999. Two hundred nine patients who were potent before brachytherapy and who at the time of the survey were not receiving hormonal therapy were mailed the specific erectile questions of the International Index of Erectile Function (IIEF) questionnaire with a self-addressed stamped envelope. The questionnaire consisted of 5 questions, with a maximal score of 25. Of the 209 patients, 181 (87%) completed and returned the questionnaire. The mean and median follow-up was 40.4±14.9 and 40.6 months, respectively (range 19-75). Preimplant erectile function was assigned using a three-tiered scoring system (2 = erections always or nearly always sufficient for vaginal penetration; 1 = erections sufficient for vaginal penetration but considered suboptimal; 0 = the inability to obtain erections and/or erections inadequate for vaginal penetration). Postimplant potency was defined as an IIEF score ≥11. The clinical parameters evaluated for erectile function included patient age, preimplant potency, clinical T-stage, pretreatment prostate-specific antigen level, Gleason score, elapsed time after implantation, hypertension, diabetes mellitus, and tobacco consumption. Treatment parameters included radiation dose to the prostate gland, use of hormonal manipulation, use of supplemental external beam radiotherapy (EBRT), choice of isotope, prostate volume, and planning volume. The efficacy of sildenafil citrate in brachytherapy-induced erectile dysfunction (ED) was also evaluated. Results: Pretreatment erectile function scores of 2 and 1 were assigned to 125 and 56 patients, respectively. With a 6-year follow

  8. The american brachytherapy society recommendations for permanent prostate brachytherapy postimplant dosimetric analysis

    International Nuclear Information System (INIS)

    Nag, Subir; Bice, William; Wyngaert, Keith de; Prestidge, Bradley; Stock, Richard; Yu Yan

    2000-01-01

    Purpose: The purpose of this report is to establish guidelines for postimplant dosimetric analysis of permanent prostate brachytherapy. Methods: Members of the American Brachytherapy Society (ABS) with expertise in prostate dosimetry evaluation performed a literature review and supplemented with their clinical experience formulated guidelines for performing and analyzing postimplant dosimetry of permanent prostate brachytherapy. Results: The ABS recommends that postimplant dosimetry should be performed on all patients undergoing permanent prostate brachytherapy for optimal patient care. At present, computed tomography (CT)-based dosimetry is recommended, based on availability cost and the ability to image the prostate as well as the seeds. Additional plane radiographs should be obtained to verify the seed count. Until the ideal postoperative interval for CT scanning has been determined, each center should perform dosimetric evaluation of prostate implants at a consistent postoperative interval. This interval should be reported. Isodose displays should be obtained at 50%, 80%, 90%, 100%, 150%, and 200% of the prescription dose and displayed on multiple cross-sectional images of the prostate. A dose-volume histogram (DVH) of the prostate should be performed and the D 90 (dose to 90% of the prostate gland) reported by all centers. Additionally, the D 80, D 100, the fractional V 80, V 90, V 100, V 150, and V 200, (i.e., the percentage of prostate volume receiving 80%, 90%, 100%, 150%, and 200% of the prescribed dose, respectively), the rectal, and urethral doses should be reported and ultimately correlated with clinical outcome in the research environment. On-line real-time dosimetry, the effects of dose heterogeneity, and the effects of tissue heterogeneity need further investigation. Conclusion: It is essential that postimplant dosimetry should be performed on all patients undergoing permanent prostate brachytherapy. Guidelines were established for the performance

  9. Circulating progesterone dynamics after intravaginal instillation of prostaglandin-F2α to lactating dairy cows.

    Science.gov (United States)

    Wijma, R; Stangaferro, M L; Giordano, J O

    2016-06-01

    Our objectives were to evaluate circulating progesterone (P4) concentration dynamics and test the feasibility of inducing luteal regression after intravaginal (IVG) instillation of the PGF2α analogue dinoprost (PGF) in lactating dairy cows. In two experiments, cows were synchronized using the Ovsynch protocol to induce the formation of a corpus luteum (CL). Cows with at least one functional (P4 ≥1 ng/mL) CL ≥15 mm 7.5 days after Ovsynch remained in the studies. In experiment 1, cows (n = 31) were stratified by parity group and received 5 mL of saline IVG (SAL-IVG, n = 6), 25 mg of PGF intramuscular (IM) (PGF25-IM, n = 7), 25 mg of PGF IVG (PGF25-IVG, n = 6), 50 mg of PGF IVG (PGF50-IVG, n = 6), and 125 mg of PGF IVG (PGF125-IVG, n = 6). Experiment 2 was conducted to test the hypothesis that IVG instillation of two 25 mg doses of PGF 12 hours apart would be more effective than a 25- or 50-mg dose in a single application. Cows (n = 32) were stratified by parity and received SAL-IVG (n = 7), PGF25-IM (n = 7), PGF25-IVG (n = 6), and PGF50-IVG (n = 6) as in experiment 1, whereas another group received two IVG instillations of 25 mg of PGF 12 hours apart (PGF25-2X-IVG, n = 6). Blood was collected at -1 hour, every 6 hours from 0 hour to 24 hours, and every 12 hours up to 96 hours after treatment (trt). In experiment 1, there was an effect of trt (P cows in the SAL-IVG group from 12 to 96 hours after trt. Although an initial decline in P4 concentrations was induced in all PGF-treated cows, some cows in the IVG-treated groups presented a rebound in plasma P4, indicating CL recovery. More cows in the PGF25-IVG and PGF125-IVG groups than in the PGF50-IVG and PGF25-IM groups presented CL recovery, suggesting that greater doses of PGF may not necessarily improve CL regression. In experiment 2, there was an effect of trt (P Cows in the PGF25-2X-IVG group had a P4 profile that was similar to that of cows in the PGF25-IM group and

  10. Biology of dose rate in brachytherapy

    International Nuclear Information System (INIS)

    Brenner, David J.

    1995-01-01

    Purpose: This course is designed for practitioners and beginners in brachytherapy. The aim is to review biological principles underlying brachytherapy, to understand why current treatment regimes are the way they are, and to discuss what the future may hold in store. Brachytherapy has a long history. It was suggested as long ago as 1903 by Alexander Graham Bell, and the optimal application of this technique has been a subject of debate ever since. 'Brachy' means 'short', and the essential features of conventional brachytherapy are: positioning of the source a short distance from, or in, the tumor, allowing good dose distributions; short overall treatment times, to counter tumor repopulation; low dose rate, enabling a good therapeutic advantage between tumor control and damage to late-responding tissue. The advantages of good dose distributions speak for themselves; in some situations, as we shall see, computer-based dose optimization can be used to improve them still further. The advantages of short overall times stem from the fact that accelerated repopulation of the tumor typically begins a few weeks after the start of a radiation treatment. If all the radiation can be crammed in before that time, the risks of tumor repopulation can be considerably reduced. In fact even external-beam radiotherapy is moving in this direction, with the use of highly accelerated protocols. The advantages of low dose rate stem from the differential response to fractionation of early- and late-responding tissues. Essentially, lowering the dose rate spares late-responding tissue more than it does early-responding tissue such as tumors. We shall also discuss some recent innovations in the context of the general principles that have been outlined. For example, High dose rate brachytherapy, particularly for the uterine cervix: Does it work? If so, when and why? Use of Ir-192 sources, with a half life of 70 days: Should corrections be made for changing biological effectiveness as the dose

  11. Caudal epidural anesthesia during intracavitary brachytherapy for cervical cancer

    International Nuclear Information System (INIS)

    Isoyama-Shirakawa, Yuko; Abe, Madoka; Nakamura, Katsumasa

    2015-01-01

    It has been suggested that pain control during intracavitary brachytherapy for cervical cancer is insufficient in most hospitals in Japan. Our hospital began using caudal epidural anesthesia during high-dose-rate (HDR) intracavitary brachytherapy in 2011. The purpose of the present study was to retrospectively investigate the effects of caudal epidural anesthesia during HDR intracavitary brachytherapy for cervical cancer patients. Caudal epidural anesthesia for 34 cervical cancer patients was performed during HDR intracavitary brachytherapy between October 2011 and August 2013. We used the patients' self-reported Numeric Rating Scale (NRS) score at the first session of HDR intracavitary brachytherapy as a subjective evaluation of pain. We compared NRS scores of the patients with anesthesia with those of 30 patients who underwent HDR intracavitary brachytherapy without sacral epidural anesthesia at our hospital between May 2010 and August 2011. Caudal epidural anesthesia succeeded in 33 patients (97%), and the NRS score was recorded in 30 patients. The mean NRS score of the anesthesia group was 5.17 ± 2.97, significantly lower than that of the control group's 6.80 ± 2.59 (P = 0.035). The caudal epidural block resulted in no side-effects. Caudal epidural anesthesia is an effective and safe anesthesia option during HDR intracavitary brachytherapy for cervical cancer. (author)

  12. Iridium-192 sources production for brachytherapy use

    International Nuclear Information System (INIS)

    Rostelato, Maria Elisa Chuery Martins

    1997-01-01

    The incidence of cancer increases every year in Brazil and turns out to be one of the most important causes of mortality. Some of the patients are treated with brachytherapy, a form of lesion treatment which is based on the insertion of sources into tumors, in this particular case, activated iridium wires. During this process, the ionizing radiation efficiently destroys the malignant cells. These iridium wires have a nucleus made out of an iridium-platinum alloy 20-30/70-80 of 0,1 mm in diameter either coated by platinum or encased in a platinum tube. The technique consists in irradiating the wire in the reactor neutron flux in order to produce iridium-192. The linear activity goes from 1 mCi/cm to 4 mCi/cm and the basic characteristic, which is required, is the homogeneity of the activation along the wire. It should not present a dispersion exceeding 5% on a wire measuring 50 cm in length, 0.5 mm or 0.3 mm in diameter. Several experiments were carried out in order to define the activation parameters. Wires from different origins were analyzed. It was concluded that United States of America and France wires were found to be perfectly adequate for brachytherapy purposes and have therefore been sent to specialized hospitals and successfully applied to cancer patients. Considering that the major purpose of this work is to make this product more accessible in Brazil, at a cost reflecting the Brazilian reality, the IPEN is promoting the preparation of iridium-192 sources to be used in brachytherapy, on a national level. (author)

  13. Perioperative interstitial brachytherapy for recurrent keloid scars

    International Nuclear Information System (INIS)

    Rio, E.; Bardet, E.; Peuvrel, P.; Martinet, L.; Perrot, P.; Baraer, F.; Loirat, Y.; Sartre, J.Y.; Malard, O.; Ferron, C.; Dreno, B.

    2010-01-01

    Purpose: Evaluation of the results of perioperative interstitial brachytherapy with low dose-rate (L.D.R.) Ir-192 in the treatment of keloid scars. Patients and methods: We performed a retrospective analysis of 73 histologically confirmed keloids (from 58 patients) resistant to medico surgical treated by surgical excision plus early perioperative brachytherapy. All lesions were initially symptomatic. Local control was evaluated by clinical evaluation. Functional and cosmetic results were assessed in terms of patient responses to a self-administered questionnaire. Results: Median age was 28 years (range 13-71 years). Scars were located as follows: 37% on the face, 32% on the trunk or abdomen, 16% on the neck, and 15% on the arms or legs. The mean delay before loading was four hours (range, 1-6 h). The median dose was 20 Gy (range, 15-40 Gy). Sixty-four scars (from 53 patients) were evaluated. Local control was 86% (follow-up, 44.5 months; range, 14-150 months). All relapses occurred early within 2 years posttreatment. At 20 months, survival without recurrence was significantly lower when treated lengths were more than 6 cm long. The rate was 100% for treated scars below 4.5 cm in length, 95% (95% CI: 55-96) for those 4.5-6 cm long, and 75% (95% CI: 56-88) beyond 6 cm (p = 0.038). Of the 35 scars (28 patients) whose results were reassessed, six remained symptomatic and the esthetic results were considered to be good in 51% (18/35) and average in 37% (13/35) (median follow-up, 70 months; range, 16-181 months). Conclusion: Early perioperative L.D.R. brachytherapy delivering 20 Gy at 5 mm reduced the rate of recurrent keloids resistant to other treatments and gave good functional results. (authors)

  14. Engineering a segmented dual-reservoir polyurethane intravaginal ring for simultaneous prevention of HIV transmission and unwanted pregnancy.

    Directory of Open Access Journals (Sweden)

    Justin T Clark

    Full Text Available The HIV/AIDS pandemic and its impact on women prompt the investigation of prevention strategies to interrupt sexual transmission of HIV. Long-acting drug delivery systems that simultaneously protect womenfrom sexual transmission of HIV and unwanted pregnancy could be important tools in combating the pandemic. We describe the design, in silico, in vitro and in vivo evaluation of a dual-reservoir intravaginal ring that delivers the HIV-1 reverse transcriptase inhibitor tenofovir and the contraceptive levonorgestrel for 90 days. Two polyether urethanes with two different hard segment volume fractions were used to make coaxial extruded reservoir segments with a 100 µm thick rate controlling membrane and a diameter of 5.5 mm that contain 1.3 wt% levonorgestrel. A new mechanistic diffusion model accurately described the levonorgestrel burst release in early time points and pseudo-steady state behavior at later time points. As previously described, tenofovir was formulated as a glycerol paste and filled into a hydrophilic polyurethane, hollow tube reservoir that was melt-sealed by induction welding. These tenofovir-eluting segments and 2 cm long coaxially extruded levonorgestrel eluting segments were joined by induction welding to form rings that released an average of 7.5 mg tenofovir and 21 µg levonorgestrel per day in vitro for 90 days. Levonorgestrel segments placed intravaginally in rabbits resulted in sustained, dose-dependent levels of levonorgestrel in plasma and cervical tissue for 90 days. Polyurethane caps placed between segments successfully prevented diffusion of levonorgestrel into the tenofovir-releasing segment during storage.Hydrated rings endured between 152 N and 354 N tensile load before failure during uniaxial extension testing. In summary, this system represents a significant advance in vaginal drug delivery technology, and is the first in a new class of long-acting multipurpose prevention drug delivery systems.

  15. Analytical Method Validation of High-Performance Liquid Chromatography and Stability-Indicating Study of Medroxyprogesterone Acetate Intravaginal Sponges

    Directory of Open Access Journals (Sweden)

    Nidal Batrawi

    2017-02-01

    Full Text Available Medroxyprogesterone acetate is widely used in veterinary medicine as intravaginal dosage for the synchronization of breeding cycle in ewes and goats. The main goal of this study was to develop reverse-phase high-performance liquid chromatography method for the quantification of medroxyprogesterone acetate in veterinary vaginal sponges. A single high-performance liquid chromatography/UV isocratic run was used for the analytical assay of the active ingredient medroxyprogesterone. The chromatographic system consisted of a reverse-phase C18 column as the stationary phase and a mixture of 60% acetonitrile and 40% potassium dihydrogen phosphate buffer as the mobile phase; the pH was adjusted to 5.6. The method was validated according to the International Council for Harmonisation (ICH guidelines. Forced degradation studies were also performed to evaluate the stability-indicating properties and specificity of the method. Medroxyprogesterone was eluted at 5.9 minutes. The linearity of the method was confirmed in the range of 0.0576 to 0.1134 mg/mL ( R 2 > 0.999. The limit of quantification was shown to be 3.9 µg/mL. Precision and accuracy ranges were found to be %RSD <0.2 and 98% to 102%, respectively. Medroxyprogesterone capacity factor value of 2.1, tailing factor value of 1.03, and resolution value of 3.9 were obtained in accordance with ICH guidelines. Based on the obtained results, a rapid, precise, accurate, sensitive, and cost-effective analysis procedure was proposed for quantitative determination of medroxyprogesterone in vaginal sponges. This analytical method is the only available method to analyse medroxyprogesterone in veterinary intravaginal dosage form.

  16. Ischiorectal abscess and ischiorectal-vaginal fistula as delayed complications of posterior intravaginal slingplasty: a case report.

    Science.gov (United States)

    Chen, Heidi Wen-Chu; Guess, Marsha K; Connell, Kathleen A; Bercik, Richard S

    2009-10-01

    Synthetic meshes have been used extensively to augment surgical management of pelvic organ prolapses. Posterior intravaginal sling (IVS) is a technique used for correcting vaginal vault/apical prolapse, posterior vaginal prolapse or rectocele. There are limited data on long-term safety of this procedure. In a subanalysis of the IVS tapes from the SUSPEND trial performed secondary to the large number of patients with complications of suburethral sling erosions after IVS, it was noted that the sling erosion tended to have a delayed presentation secondary to poor incorporation of the mesh. A 48-year-old woman with cystocele, uterine prolapse and rectocele had undergone total vaginal hysterectomy, mesh-augmented anterior repair, posterior colporrhaphy and posterior intravaginal slingplasty (IVS) in July 2005. Thirty months after the surgery, she presented with gradual symptoms of copious vaginal discharge for several weeks followed by constant right buttock pain and swelling. Examination was notable for intact mesh with no signs of erosion and a 3-cm induration deep within the right buttock. Computed tomography suggested a pelvic abscess. Magnetic resonance imaging confirmed a right ischiorectal fossa abscess and a vaginal fistula. The patient underwent sling excision, right ischiorectal fossa exploration and vaginal fistula repair. A fistulous tract was found to extend along the intact sling from the vaginal epithelium toward the right ischiorectal fossa. At 2 months' followup, there were no recurrences or other complications. This is the first report of a delayed complication of an ischiorectal abscess associated with an ischiorectal-vaginal fistula that presented 30 months after the placement of a posterior IVS.

  17. High dose rate endobronchial brachytherapy - treatment technique

    International Nuclear Information System (INIS)

    Carvalho, Heloisa de Andrade; Aisen, Salim; Haddad, Cecilia Maria Kalil; Nadalin, Wladimir; Pedreira Junior, Wilson Leite; Chavantes, Maria Cristina

    1998-01-01

    High dose rate endobronchial brachytherapy is efficient in symptom relief due to obstructive endobronchial malignancies. However, it's role in survival improvement for patients with lung cancer is not yet established. The use of this treatment in increasing, specially in the developing countries. The purpose of this paper is to present the treatment technique used in the Radiotherapy Department of the Hospital da Clinicas, University of Sao Paulo, based on an experience of 60 cases treated with 180 procedures. Some practical suggestions and rules adopted in the Department are described. The severe complications rate is 6.7%, demonstrating an adequate patient selection associated with the technique utilized. (author)

  18. An afterloading brachytherapy device utilizing thermoplastic material

    International Nuclear Information System (INIS)

    Kim, T.H.; Gerbi, J.B.; Deibel, F.C.; Khan, F.M.; Priest, J.R.

    1989-01-01

    An afterloading brachytherapy device for treatment of residual cancer in an enucleated orbit with two cesium-137 sources was designed using a thermoplastic material, Aquaplast. The device consists of a face-mask support held in place with elastic bands around the head and an acrylic afterloading applicator. The device is very easy to make, holds the sources firmly in place, allows full mobility of the patient, and gives excellent dose distribution to the target area. It was easily tolerated by a 7-year-old child during the 50 h of treatment. (author). 3 refs.; 4 figs

  19. A study of Brachytherapy for Intraocular Tumor

    International Nuclear Information System (INIS)

    Ji, Kwang Soo; Yoo, Dae Hyun; Lee, Sung Goo; Kim, Jae Hu; Ji, Young Hun

    1996-01-01

    The eye enucleation or external-beam radiation therapy that has been commonly used for the treatment of intraocular tumor have demerits of visual loss and in deficiency of effective tumor dose. Recently, brachytherapy using the plaques containing radioisotope-now treatment method that decrease the demerits of the above mentioned treatment methods and increase the treatment effect-is introduced and performed in the countries, Our purpose of this research is to design suitable shape of plaque for the ophthalmic brachytherapy, and to measure absorbed doses of Ir-192 ophthalmic plaque and thereby calculate the exact radiation dose of tumor and it's adjacent normal tissue. In order to brachytherapy for intraocular tumor, 1. to determine the eye model and selected suitable radioisotope 2. to design the suitable shape of plaque 3. to measure transmission factor and dose distribution for custom made plaques 4. to compare with the these data and results of computer dose calculation models. The result were as followed. 1. Eye model was determined as a 25 mm diameter sphere, Ir-192 was considered the most appropriate as radioisotope for brachytherapy, because of the size, half, energy and availability. 2. Considering the biological response with human tissue and protection of exposed dose, we made the plaques with gold, of which size were 15 mm, 17 mm and 20 mm in diameter, and 1.5 mm in thickness. 3. Transmission factor of plaques are all 0.71 with TLD and film dosimetry at the surface of plaques and 0.45, 0.49 at 1.5 mm distance of surface, respectively. 4. As compared the measured data for the plaque with Ir-192 seeds to results of computer dose calculation model by Gary Luxton et al. and CAP-PLAN (Radiation Treatment Planning System), absorbed doses are within ±10% and distance deviations are within 0.4 mm Maximum error is -11.3% and 0.8 mm, respectively. As a result of it, we can treat the intraocular tumor more effectively by using custom made gold plaque and Ir-192

  20. High dose rate brachytherapy for superficial cancer of the esophagus

    International Nuclear Information System (INIS)

    Maingon, Philippe; D'Hombres, Anne; Truc, Gilles; Barillot, Isabelle; Michiels, Christophe; Bedenne, Laurent; Horiot, Jean Claude

    2000-01-01

    Purpose: We analyzed our experience with external radiotherapy, combined modality treatment, or HDR brachytherapy alone to limited esophageal cancers. Methods and Materials: From 1991 to 1996, 25 patients with limited superficial esophagus carcinomas were treated by high dose rate brachytherapy. The mean age was 63 years (43-86 years). Five patients showed superficial local recurrence after external radiotherapy. Eleven patients without invasion of the basal membrane were staged as Tis. Fourteen patients with tumors involving the submucosa without spreading to the muscle were staged as T1. Treatment consisted of HDR brachytherapy alone in 13 patients, external radiotherapy and brachytherapy in 8 cases, and concomitant chemo- and radiotherapy in 4 cases. External beam radiation was administered to a total dose of 50 Gy using 2 Gy daily fractions in 5 weeks. In cases of HDR brachytherapy alone (13 patients), 6 applications were performed once a week. Results: The mean follow-up is 31 months (range 24-96 months). Twelve patients received 2 applications and 13 patients received 6 applications. Twelve patients experienced a failure (48%), 11/12 located in the esophagus, all of them in the treated volume. One patient presented an isolated distant metastasis. In the patients treated for superficial recurrence, 4/5 were locally controlled (80%) by brachytherapy alone. After brachytherapy alone, 8/13 patients were controlled (61%). The mean disease-free survival is 14 months (1-36 months). Overall survival is 76% at 1 year, 37% at 2 years, and 14% at 3 years. Overall survival for Tis patients is 24% vs. 20% for T1 (p 0.83). Overall survival for patients treated by HDR brachytherapy alone is 43%. One patient presented with a fistula with local failure after external radiotherapy and brachytherapy. Four stenosis were registered, two were diagnosed on barium swallowing without symptoms, and two required dilatations. Conclusion: High dose rate brachytherapy permits the treating

  1. SU-E-T-564: Multi-Helix Rotating Shield Brachytherapy for Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dadkhah, H; Wu, X [University of Iowa, Iowa City, IA (United States); Flynn, R; Kim, Y [University of Iowa Hospitals and Clinics, Iowa City, IA (United States)

    2015-06-15

    Purpose: To present a novel and practical brachytherapy technique, called multi-helix rotating shield brachytherapy (H-RSBT), for the precise positioning of a partial shield in a curved applicator. H-RSBT enables RSBT delivery using only translational motion of the radiation source/shield combination. H-RSBT overcomes the challenges associated with previously proposed RSBT approaches based on a serial (S-RSBT) step-and-shoot delivery technique, which required independent translational and rotational motion. Methods: A Fletcher-type applicator, compatible with the combination of a Xoft Axxent™ electronic brachytherapy source and a 0.5 mm thick tungsten shield, is proposed. The wall of the applicator contains six evenly-spaced helical keyways that rigidly define the emission direction of the shield as a function of depth. The shield contains three protruding keys and is attached to the source such that it rotates freely. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients representative of a wide range of high-risk clinical target volume (HR-CTV) shapes and applicator positions. The number of beamlets used in the treatment planning process was nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. For all the treatment plans the EQD2 of the HR-CTV was escalated until the EQD{sub 2cc} tolerance of either the bladder, rectum, or sigmoid colon was reached. Results: Treatment times for H-RSBT tended to be shorter than for S-RSBT, with changes of −38.47% to 1.12% with an average of −8.34%. The HR-CTV D{sub 90} changed by −8.81% to 2.08% with an average of −2.46%. Conclusion: H-RSBT is a mechanically feasible technique in the curved applicators needed for cervical cancer brachytherapy. S-RSBT and H-RSBT dose distributions were clinically equivalent for all patients

  2. Source position verification and dosimetry in HDR brachytherapy using an EPID

    International Nuclear Information System (INIS)

    Smith, R. L.; Taylor, M. L.; McDermott, L. N.; Franich, R. D.; Haworth, A.; Millar, J. L.

    2013-01-01

    Purpose: Accurate treatment delivery in high dose rate (HDR) brachytherapy requires correct source dwell positions and dwell times to be administered relative to each other and to the surrounding anatomy. Treatment delivery inaccuracies predominantly occur for two reasons: (i) anatomical movement or (ii) as a result of human errors that are usually related to incorrect implementation of the planned treatment. Electronic portal imaging devices (EPIDs) were originally developed for patient position verification in external beam radiotherapy and their application has been extended to provide dosimetric information. The authors have characterized the response of an EPID for use with an 192 Ir brachytherapy source to demonstrate its use as a verification device, providing both source position and dosimetric information.Methods: Characterization of the EPID response using an 192 Ir brachytherapy source included investigations of reproducibility, linearity with dose rate, photon energy dependence, and charge build-up effects associated with exposure time and image acquisition time. Source position resolution in three dimensions was determined. To illustrate treatment verification, a simple treatment plan was delivered to a phantom and the measured EPID dose distribution compared with the planned dose.Results: The mean absolute source position error in the plane parallel to the EPID, for dwells measured at 50, 100, and 150 mm source to detector distances (SDD), was determined to be 0.26 mm. The resolution of the z coordinate (perpendicular distance from detector plane) is SDD dependent with 95% confidence intervals of ±0.1, ±0.5, and ±2.0 mm at SDDs of 50, 100, and 150 mm, respectively. The response of the EPID is highly linear to dose rate. The EPID exhibits an over-response to low energy incident photons and this nonlinearity is incorporated into the dose calibration procedure. A distance (spectral) dependent dose rate calibration procedure has been developed. The

  3. Applying gold nanoparticles as tumor-vascular disrupting agents during brachytherapy: estimation of endothelial dose enhancement

    International Nuclear Information System (INIS)

    Ngwa, Wilfred; Makrigiorgos, G Mike; Berbeco, Ross I

    2010-01-01

    Tumor vascular disrupting agents (VDAs) represent a promising approach to the treatment of cancer, in view of the tumor vasculature's pivotal role in tumor survival, growth and metastasis. VDAs targeting the tumor's dysmorphic endothelial cells can cause selective and rapid occlusion of the tumor vasculature, leading to tumor cell death from ischemia and extensive hemorrhagic necrosis. In this study, the potential for applying gold nanoparticles (AuNPs) as VDAs, during brachytherapy, is examined. Analytic calculations based on the electron energy loss formula of Cole were carried out to estimate the endothelial dose enhancement caused by radiation-induced photo/Auger electrons originating from AuNPs targeting the tumor endothelium. The endothelial dose enhancement factor (EDEF), representing the ratio of the dose to the endothelium with and without gold nanoparticles was calculated for different AuNP local concentrations, and endothelial cell thicknesses. Four brachytherapy sources were investigated, I-125, Pd-103, Yb-169, as well as 50 kVp x-rays. The results reveal that, even at relatively low intra-vascular AuNP concentrations, ablative dose enhancement to tumor endothelial cells due to photo/Auger electrons from the AuNPs can be achieved. Pd-103 registered the highest EDEF values of 7.4-271.5 for local AuNP concentrations ranging from 7 to 350 mg g -1 , respectively. Over the same concentration range, I-125, 50 kVp and Yb-169 yielded values of 6.4-219.9, 6.3-214.5 and 4.0-99.7, respectively. Calculations of the EDEF as a function of endothelial cell thickness showed that lower energy sources like Pd-103 reach the maximum EDEF at smaller thicknesses. The results also reveal that the highest contribution to the EDEF comes from Auger electrons, apparently due to their shorter range. Overall, the data suggest that ablative dose enhancement to tumor endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs as adjuvants to brachytherapy, with

  4. Applying gold nanoparticles as tumor-vascular disrupting agents during brachytherapy: estimation of endothelial dose enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Ngwa, Wilfred; Makrigiorgos, G Mike; Berbeco, Ross I, E-mail: mmakrigiorgos@lroc.harvard.ed [Department of Radiation Oncology, Division of Medical Physics and Biophysics, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115 (United States)

    2010-11-07

    Tumor vascular disrupting agents (VDAs) represent a promising approach to the treatment of cancer, in view of the tumor vasculature's pivotal role in tumor survival, growth and metastasis. VDAs targeting the tumor's dysmorphic endothelial cells can cause selective and rapid occlusion of the tumor vasculature, leading to tumor cell death from ischemia and extensive hemorrhagic necrosis. In this study, the potential for applying gold nanoparticles (AuNPs) as VDAs, during brachytherapy, is examined. Analytic calculations based on the electron energy loss formula of Cole were carried out to estimate the endothelial dose enhancement caused by radiation-induced photo/Auger electrons originating from AuNPs targeting the tumor endothelium. The endothelial dose enhancement factor (EDEF), representing the ratio of the dose to the endothelium with and without gold nanoparticles was calculated for different AuNP local concentrations, and endothelial cell thicknesses. Four brachytherapy sources were investigated, I-125, Pd-103, Yb-169, as well as 50 kVp x-rays. The results reveal that, even at relatively low intra-vascular AuNP concentrations, ablative dose enhancement to tumor endothelial cells due to photo/Auger electrons from the AuNPs can be achieved. Pd-103 registered the highest EDEF values of 7.4-271.5 for local AuNP concentrations ranging from 7 to 350 mg g{sup -1}, respectively. Over the same concentration range, I-125, 50 kVp and Yb-169 yielded values of 6.4-219.9, 6.3-214.5 and 4.0-99.7, respectively. Calculations of the EDEF as a function of endothelial cell thickness showed that lower energy sources like Pd-103 reach the maximum EDEF at smaller thicknesses. The results also reveal that the highest contribution to the EDEF comes from Auger electrons, apparently due to their shorter range. Overall, the data suggest that ablative dose enhancement to tumor endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs as adjuvants to

  5. Applying gold nanoparticles as tumor-vascular disrupting agents during brachytherapy: estimation of endothelial dose enhancement

    Science.gov (United States)

    Ngwa, Wilfred; Makrigiorgos, G. Mike; Berbeco, Ross I.

    2010-11-01

    Tumor vascular disrupting agents (VDAs) represent a promising approach to the treatment of cancer, in view of the tumor vasculature's pivotal role in tumor survival, growth and metastasis. VDAs targeting the tumor's dysmorphic endothelial cells can cause selective and rapid occlusion of the tumor vasculature, leading to tumor cell death from ischemia and extensive hemorrhagic necrosis. In this study, the potential for applying gold nanoparticles (AuNPs) as VDAs, during brachytherapy, is examined. Analytic calculations based on the electron energy loss formula of Cole were carried out to estimate the endothelial dose enhancement caused by radiation-induced photo/Auger electrons originating from AuNPs targeting the tumor endothelium. The endothelial dose enhancement factor (EDEF), representing the ratio of the dose to the endothelium with and without gold nanoparticles was calculated for different AuNP local concentrations, and endothelial cell thicknesses. Four brachytherapy sources were investigated, I-125, Pd-103, Yb-169, as well as 50 kVp x-rays. The results reveal that, even at relatively low intra-vascular AuNP concentrations, ablative dose enhancement to tumor endothelial cells due to photo/Auger electrons from the AuNPs can be achieved. Pd-103 registered the highest EDEF values of 7.4-271.5 for local AuNP concentrations ranging from 7 to 350 mg g-1, respectively. Over the same concentration range, I-125, 50 kVp and Yb-169 yielded values of 6.4-219.9, 6.3-214.5 and 4.0-99.7, respectively. Calculations of the EDEF as a function of endothelial cell thickness showed that lower energy sources like Pd-103 reach the maximum EDEF at smaller thicknesses. The results also reveal that the highest contribution to the EDEF comes from Auger electrons, apparently due to their shorter range. Overall, the data suggest that ablative dose enhancement to tumor endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs as adjuvants to brachytherapy, with lower

  6. How to optimize therapeutic ratio in brachytherapy of head and neck squamous cell carcinoma?

    International Nuclear Information System (INIS)

    Mazeron, J.J.; Simon, J.M.; Hardiman, C.; Gerbaulet, A.

    1998-01-01

    Considerable experience has been accumulated with low dose rate (LDR) brachytherapy in the treatment of squamous cell carcinoma of the oral cavity and oropharynx, 4 cm or less in diameter. Recent analysis of large clinical series provided data indicating that modalities of LDR brachytherapy should be optimized in treating these tumours for increasing therapeutic ratio. LDR brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with the last two modalities are discussed in comparison with those achieved with LDR brachytherapy. (orig.)

  7. Estimation of the optimal brachytherapy utilisation rate in the treatment of vaginal cancer and comparison with patterns of care

    International Nuclear Information System (INIS)

    Thompson, Stephen R.; Delaney, Geoff P.; Gabriel, Gabriel S.; Barton, Michael B.; Jacob, Susannah

    2012-01-01

    Having previously modelled the optimal proportion of uterine cervix and corpus cancers that should be treated with brachytherapy (BT), we aimed to complete the assessment of the role of BT for gynaecological cancers by estimating the optimal proportion of vaginal cancer cases that should be treated with BT, the optimal BT utilisation (BTU) rate for vaginal cancer. We compared this with actual vaginal BTU and assessed quality of BT for vaginal cancer by a Patterns-of-Care Study (POCS). Evidence-based guidelines were used to construct an optimal BTU decision tree for vaginal cancer. Searches of the epidemiological literature to ascertain the proportion of patients who fulfilled the criteria for BT were conducted. The robustness of the model was tested by sensitivity analyses and by peer review. A retrospective POCS of BT in New South Wales (NSW) for 2003 was conducted, and actual BTU for vaginal cancer was determined. Differences between optimal and actual BTU were assessed. Quality of BT for vaginal cancer was compared with published benchmarks. The optimal vaginal cancer BTU rate was estimated to be 85% (range 81–87%). In NSW in 2003, actual vaginal cancer BTU was only 42% (95% confidence interval 22–62%). In NSW, only nine patients were treated, all with intra-vaginal cylinders, and two of four to lower than recommended doses. BT for vaginal cancers is under utilised in NSW compared with the proposed optimal models of care. BT quality may have been suboptimal and this may relate to the rarity of this disease.

  8. Coatings of nanoparticles applied to brachytherapy treatments

    International Nuclear Information System (INIS)

    Gonzalez, Andreza A.D.C.C.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Rodrigues, Bruna T.; Souza, Daiane C.B.; Zeituni, Carlos A.; Nogueira, Beatriz R.

    2017-01-01

    Brachytherapy is a treatment for cancer in which the radiation is placed close or in contact with the region to be treated saving the surrounding healthy tissues. Nanotechnology is the science that studies the properties of nanometric materials. Nanobrachytherapy in a new field that unites the advantages of brachytherapy with the small size in the nanoparticle, resulting in an even less invasive treatment. In view of the synthesis of the nanoparticles and their use, there is a fundamental role that is made by the coatings, which not only have the function of avoiding the aggregation of particles, but also stabilize and control their functional properties. Among the range of coatings, the most outstanding are polyethylene glycol (PEG) and gum arabica (GA). PEG improves the surface properties of nanoparticles and presents high stability under biomedical conditions. After the synthesis of gold nanoparticles was developed, PEG and gum arabica were successfully incorporated into the surface. In a vial of pyrex, 1 ml of coating agent and 1 ml of nanoparticles was left under gentle shaking for 2 hours. Incorporation was confirmed by DLS and HRTEM. GA requires further study. (author)

  9. A study of brachytherapy for intraocular tumor

    International Nuclear Information System (INIS)

    Ji, Yung Hoon; Lee, Dong Han; Ko, Kyung Hwan; Lee, Tae Won; Lee, Sung Koo; Choi, Moon Sik

    1994-12-01

    Our purpose of this study is to perform brachytherapy for intraocular tumor. The result were as followed. 1. Eye model was determined as a 25 mm diameter sphere. Ir-192 was considered the most appropriate as radioisotope for brachytherapy, because of the size, half, energy and availability. 2. Considering the biological response with human tissue and protection of exposed dose, we made the plaques with gold, of which size were 15 mm, 17 mm and 20 mm in diameter, and 1.5 mm in thickness. 3. Transmission factor of plaques are all 0.71 with TLD and film dosimetry at the surface of plaques and 0.45, 0.49 at 1.5 mm distance of surface, respectively. 4. As compared the measured data for the plaque with Ir-192 seeds to results of computer dose calculation model by Gary Luxton et al. and CAP-PLAN (Radiation Treatment Planning System), absorbed doses are within ±10% and distance deviations are within 0.4 mm. Maximum error is -11.3% and 0.8 mm, respectively. 7 figs, 2 tabs, 28 refs. (Author)

  10. Coatings of nanoparticles applied to brachytherapy treatments

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Andreza A.D.C.C.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Rodrigues, Bruna T.; Souza, Daiane C.B.; Zeituni, Carlos A.; Nogueira, Beatriz R., E-mail: ccg.andreza@gmail.com, E-mail: elisaros@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    Brachytherapy is a treatment for cancer in which the radiation is placed close or in contact with the region to be treated saving the surrounding healthy tissues. Nanotechnology is the science that studies the properties of nanometric materials. Nanobrachytherapy in a new field that unites the advantages of brachytherapy with the small size in the nanoparticle, resulting in an even less invasive treatment. In view of the synthesis of the nanoparticles and their use, there is a fundamental role that is made by the coatings, which not only have the function of avoiding the aggregation of particles, but also stabilize and control their functional properties. Among the range of coatings, the most outstanding are polyethylene glycol (PEG) and gum arabica (GA). PEG improves the surface properties of nanoparticles and presents high stability under biomedical conditions. After the synthesis of gold nanoparticles was developed, PEG and gum arabica were successfully incorporated into the surface. In a vial of pyrex, 1 ml of coating agent and 1 ml of nanoparticles was left under gentle shaking for 2 hours. Incorporation was confirmed by DLS and HRTEM. GA requires further study. (author)

  11. The Activity Check of Brachytherapy Isotope

    International Nuclear Information System (INIS)

    Kim, Gun Oh; Lee, Byung Koo; Kwon, Young Ho

    2004-01-01

    An isotope Ir-192, which is used in brachytherapy depends on import in whole quantities. There are a few ways for its activity. measurement using Welltype chamber or the way to rely on authentic decay table of manufacturer. In-air dosimetry using Farmer Chamber, etc. In this paper, let me introduce the way using Farmer chamber which is easier and simple. With the Farmer chamber and source calibration jig, take a measurement the activity of an isotope Ir-192 and compare the value with the value from decay table of manufacturer and check the activity of source. The result of measurement, compared the value from decay table, by ±2.1. (which belongs to recommendable value for AAPM ±5% as difference of error range). It is possible to use on clinical medicine. With the increase in use of brachytherapy, the increase of import is essential. And an accurate activity check of source is compulsory. For the activity check of source, it was possible to use Farmer chamber and source calibration jig without additional purchase of Well type chamber.

  12. Radiotherapy and Brachytherapy : Proceedings of the NATO Advanced Study Institute on Physics of Modern Radiotherapy & Brachytherapy

    CERN Document Server

    Lemoigne, Yves

    2009-01-01

    This volume collects a series of lectures presented at the tenth ESI School held at Archamps (FR) in November 2007 and dedicated to radiotherapy and brachytherapy. The lectures focus on the multiple facets of radiotherapy in general, including external radiotherapy (often called teletherapy) as well as internal radiotherapy (called brachytherapy). Radiotherapy strategy and dose management as well as the decisive role of digital imaging in the associated clinical practice are developed in several articles. Grouped under the discipline of Conformal Radiotherapy (CRT), numerous modern techniques, from Multi-Leaf Collimators (MLC) to Intensity Modulated RadioTherapy (IMRT), are explained in detail. The importance of treatment planning based upon patient data from digital imaging (Computed Tomography) is also underlined. Finally, despite the quasi- totality of patients being presently treated with gamma and X-rays, novel powerful tools are emerging using proton and light ions (like carbon ions) beams, bound to bec...

  13. Brachytherapy. High dose rate brachytherapy - Radiation protection: medical sheet ED 4287

    International Nuclear Information System (INIS)

    Celier, D.; Aubert, B.; Vidal, J.P.; Biau, A.; Lahaye, T.; Gauron, C.; Barret, C.; Boisserie, G.; Branchet, E.; Gambini, D.; Gondran, C.; Le Guen, B.; Guerin, C.; Nguyen, S.; Pierrat, N.; Sarrazin, T.; Donnarieix, D.

    2010-02-01

    After having indicated the required authorization to implement brachytherapy techniques, this document presents the various aspects and measures related to radiation protection when performing high-dose-rate brachytherapy treatments. It presents the concerned personnel, describes the operational process, indicates the associated hazards and the risk related to ionizing radiation, and describes how the risk is to be assessed and how exposure levels are to be determined (elements of risk assessment, delimitation of controlled and monitored areas, personnel classification, and choice of the dose monitoring method). It describes the various components of a risk management strategy (risk reduction, technical measures regarding the installation and the personnel, training and information, prevention and medical monitoring). It briefly presents how risk management is to be assessed, and mentions other related risks (biological risk, handling and posture, handling of heavy loads, mental workload, chemical risk)

  14. Brachytherapy. Pulsed dose rate brachytherapy - Radiation protection: medical sheet ED 4250

    International Nuclear Information System (INIS)

    Celier, D.; Aubert, B.; Vidal, J.P.; Biau, A.; Lahaye, T.; Gauron, C.; Barret, C.; Boisserie, G.; Branchet, E.; Gambini, D.; Gondran, C.; Le Guen, B.; Guerin, C.; Nguyen, S.; Pierrat, N.; Sarrazin, T.; Donnarieix, D.

    2009-06-01

    After having indicated the required authorization to implement brachytherapy techniques, this document presents the various aspects and measures related to radiation protection when performing pulsed-dose-rate brachytherapy treatments. It presents the concerned personnel, describes the operational process, indicates the associated hazards and the risk related to ionizing radiation, and describes how the risk is to be assessed and how exposure levels are to be determined (elements of risk assessment, delimitation of controlled and monitored areas, personnel classification, and choice of the dose monitoring method). It describes the various components of a risk management strategy (risk reduction, technical measures regarding the installation and the personnel, training and information, prevention and medical monitoring). It briefly presents how risk management is to be assessed, and mentions other related risks (biological risk, handling and posture, handling of heavy loads, mental workload, chemical risk)

  15. Treatment of the prostate cancer with high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Martinez, Alvaro; Torres Silva, Felipe

    2002-01-01

    The prostate cancer treatment in early stages is controversial. The high dose rate brachytherapy has been used like monotherapy or boost with external beam radiotherapy in advanced disease. This paper describes the technique and the advantages over other modalities

  16. Manual on brachytherapy. Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1992-01-01

    In addition to a basic guide to the principles of the production of ionizing radiation and to methods of radiation protection and dosimetry, this booklet includes information about radiation protection procedures for brachytherapy

  17. BRIT manual after loading brachytherapy kit for intracavitary: initial experience

    International Nuclear Information System (INIS)

    Aggarwal, Lalit M.; Mandal, Abhijit; Asthana, Anupam K.; Shahi, Uday P.; Pradhan, Satyajit

    2007-01-01

    Brachytherapy continues to serve as an important and rapidly evolving tool in the management of cancer. Technological developments in the last two decades have dramatic impact on the safe practice of brachytherapy. A wide range of brachytherapy sources and equipment are available for new therapeutic possibilities. However, decision making with regard to new brachytherapy facilities are need based and depend on the patient load, socioeconomic status of the patients, and funds available with the institution. Remote afterloading equipments are fast replacing the Manual After Loading (MAL) systems. However, keeping in view the large number of patients, who can not afford expensive treatment, the utility of manual after loading system which is inexpensive, cannot be ignored

  18. Intra-luminal brachytherapy of bile duct tumors

    International Nuclear Information System (INIS)

    Udaya Kumar Maiya, M.; Bhat, Naresh; Praveen, L.S.

    2000-01-01

    The objective of this study has been to assess the feasibility of intraluminal brachytherapy of the biliary ductal system. The technique of the procedure with its attendant problems and how to overcome the same will be discussed in detail

  19. American Brachytherapy Society consensus report for accelerated partial breast irradiation using interstitial multicatheter brachytherapy.

    Science.gov (United States)

    Hepel, Jaroslaw T; Arthur, Douglas; Shaitelman, Simona; Polgár, Csaba; Todor, Dorin; Zoberi, Imran; Kamrava, Mitchell; Major, Tibor; Yashar, Catheryn; Wazer, David E

    To develop a consensus report for the quality practice of accelerated partial breast irradiation (APBI) using interstitial multicatheter brachytherapy (IMB). The American Brachytherapy Society Board appointed an expert panel with clinical and research experience with breast brachytherapy to provide guidance for the current practice of IMB. This report is based on a comprehensive literature review with emphasis on randomized data and expertise of the panel. Randomized trials have demonstrated equivalent efficacy of APBI using IMB compared with whole breast irradiation for select patients with early-stage breast cancer. Several techniques for placement of interstitial catheters are described, and importance of three-dimensional planning with appropriate optimization is reviewed. Optimal target definition is outlined. Commonly used dosing schemas include 50 Gy delivered in pulses of 0.6-0.8 Gy/h using pulsed-dose-rate technique and 34 Gy in 10 fractions, 32 Gy in eight fractions, or 30 Gy in seven fractions using high-dose-rate technique. Potential toxicities and strategies for toxicity avoidance are described in detail. Dosimetric constraints include limiting whole breast volume that receives ≥50% of prescription dose to 0.75 (>0.85 preferred), V 150  < 45 cc, and V 200  < 14 cc. Using an optimal implant technique coupled with optimal planning and appropriate dose constraints, a low rate of toxicity and a good-to-excellent cosmetic outcome of ≥90% is expected. IMB is an effective technique to deliver APBI for appropriately selected women with early-stage breast cancer. This consensus report has been created to assist clinicians in the appropriate practice of APBI using IMB. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  20. Resolving the brachytherapy challenges with government funded hospital.

    Science.gov (United States)

    Nikam, D S; Jagtap, A S; Vinothraj, R

    2016-01-01

    The objective of this study is to rationalize the feasibility and cost-effectiveness of high dose rate (HDR) cobalt 60 (Co-60) source versus 192-Iridium (192-Ir) source brachytherapy in government funded hospitals and treatment interruption gap because of exchange of sources. A retrospective study of gynecological cancer patients, treated by radiotherapy with curative intent between April 2005 and September 2012 was conducted. We analyzed the total number of patients treated for external beam radiotherapy (EBRT) and brachytherapy (Intracavitary brachytherapy or cylindrical vaginal source). The dates for 192-Ir sources installation and the last date and first date of brachytherapy procedure before and after source installation respectively were also analyzed and calculated the gap in days for brachytherapy interruptions. The study was analyzed the records of 2005 to September 2012 year where eight 192-Ir sources were installed. The mean gap between treatment interruptions was 123.12 days (range 1-647 days). The Institutional incidence of gynecological cancer where radiotherapy was treatment modality (except ovary) is 34.9 percent. Around 52.25 percent of patients who received EBRT at this institute were referred to outside hospital for brachytherapy because of unavailability of Iridium source. The cost for 5 year duration for single cobalt source is approximately 20-22 lakhs while for 15 Iridium sources is approximately 52-53 lakhs. The combined HDR Co-60 brachytherapy and EBRT provide a useful modality in the treatment of gynecological cancer where radiotherapy is indicated, the treatment interruption because of source exchange is longer and can be minimized by using cobalt source as it is cost-effective and has 5 year working life. Thus, Co-60 source for brachytherapy is a feasible option for government funded hospitals in developing countries.

  1. Review of advanced catheter technologies in radiation oncology brachytherapy procedures

    OpenAIRE

    Zhou J; Zamdborg L; Sebastian E

    2015-01-01

    Jun Zhou,1,2 Leonid Zamdborg,1 Evelyn Sebastian1 1Department of Radiation Oncology, Beaumont Health System, 2Oakland University William Beaumont School of Medicine, Royal Oak, MI, USA Abstract: The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy ...

  2. High versus low-dose rate brachytherapy for cervical cancer.

    Science.gov (United States)

    Patankar, Sonali S; Tergas, Ana I; Deutsch, Israel; Burke, William M; Hou, June Y; Ananth, Cande V; Huang, Yongmei; Neugut, Alfred I; Hershman, Dawn L; Wright, Jason D

    2015-03-01

    Brachytherapy plays an important role in the treatment of cervical cancer. While small trials have shown comparable survival outcomes between high (HDR) and low-dose rate (LDR) brachytherapy, little data is available in the US. We examined the utilization of HDR brachytherapy and analyzed the impact of type of brachytherapy on survival for cervical cancer. Women with stages IB2-IVA cervical cancer treated with primary (external beam and brachytherapy) radiotherapy between 2003-2011 and recorded in the National Cancer Database (NCDB) were analyzed. Generalized linear mixed models and Cox proportional hazards regression were used to examine predictors of HDR brachytherapy use and the association between HDR use and survival. A total of 10,564 women including 2681 (25.4%) who received LDR and 7883 (74.6%) that received HDR were identified. Use of HDR increased from 50.2% in 2003 to 83.9% in 2011 (Puse of HDR. While patients in the Northeast were more likely to receive HDR therapy, there were no other clinical or socioeconomic characteristics associated with receipt of HDR. In a multivariable Cox model, survival was similar between the HDR and LDR groups (HR=0.93; 95% CI 0.83-1.03). Similar findings were noted in analyses stratified by stage and histology. Kaplan-Meier analyses demonstrated no difference in survival based on type of brachytherapy for stage IIB (P=0.68), IIIB (P=0.17), or IVA (P=0.16) tumors. The use of HDR therapy has increased rapidly. Overall survival is similar for LDR and HDR brachytherapy. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Image-robot coupling for the prostate brachytherapy

    International Nuclear Information System (INIS)

    Coelen, V.; Lartigau, E.; Merzouki, R.

    2009-01-01

    The results allows to contemplate a robot use in the prostate brachytherapy but equally in other applications such prostate biopsy. The tests to come are going to be directed towards on the use of a prostate phantom in order to calibrate the ultrasonography. thereafter, we contemplate the conception of an intelligent gripping system placed on the robot arm and allowing a good control in closed loop of the brachytherapy needle placement and allowing the setting up of an online monitoring. (N.C.)

  4. Rapid emission angle selection for rotating-shield brachytherapy

    International Nuclear Information System (INIS)

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Sun, Wenqing; Yang Wenjun; Wu Xiaodong

    2013-01-01

    Purpose: The authors present a rapid emission angle selection (REAS) method that enables the efficient selection of the azimuthal shield angle for rotating shield brachytherapy (RSBT). The REAS method produces a Pareto curve from which a potential RSBT user can select a treatment plan that balances the tradeoff between delivery time and tumor dose conformity. Methods: Two cervical cancer patients were considered as test cases for the REAS method. The RSBT source considered was a Xoft Axxent TM electronic brachytherapy source, partially shielded with 0.5 mm of tungsten, which traveled inside a tandem intrauterine applicator. Three anchor RSBT plans were generated for each case using dose-volume optimization, with azimuthal shield emission angles of 90°, 180°, and 270°. The REAS method converts the anchor plans to treatment plans for all possible emission angles by combining neighboring beamlets to form beamlets for larger emission angles. Treatment plans based on exhaustive dose-volume optimization (ERVO) and exhaustive surface optimization (ERSO) were also generated for both cases. Uniform dwell-time scaling was applied to all plans such that that high-risk clinical target volume D 90 was maximized without violating the D 2cc tolerances of the rectum, bladder, and sigmoid colon. Results: By choosing three azimuthal emission angles out of 32 potential angles, the REAS method performs about 10 times faster than the ERVO method. By setting D 90 to 85–100 Gy 10 , the delivery times used by REAS generated plans are 21.0% and 19.5% less than exhaustive surface optimized plans used by the two clinical cases. By setting the delivery time budget to 5–25 and 10–30 min/fx, respectively, for two the cases, the D 90 contributions for REAS are improved by 5.8% and 5.1% compared to the ERSO plans. The ranges used in this comparison were selected in order to keep both D 90 and the delivery time within acceptable limits. Conclusions: The REAS method enables efficient RSBT

  5. MO-B-BRC-01: Introduction [Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Prisciandaro, J. [University of Michigan (United States)

    2016-06-15

    Brachytherapy has proven to be an effective treatment option for prostate cancer. Initially, prostate brachytherapy was delivered through permanently implanted low dose rate (LDR) radioactive sources; however, high dose rate (HDR) temporary brachytherapy for prostate cancer is gaining popularity. Needle insertion during prostate brachytherapy is most commonly performed under ultrasound (U/S) guidance; however, treatment planning may be performed utilizing several imaging modalities either in an intra- or post-operative setting. During intra-operative prostate HDR, the needles are imaged during implantation, and planning may be performed in real time. At present, the most common imaging modality utilized for intra-operative prostate HDR is U/S. Alternatively, in the post-operative setting, following needle implantation, patients may be simulated with computed tomography (CT) or magnetic resonance imaging (MRI). Each imaging modality and workflow provides its share of benefits and limitations. Prostate HDR has been adopted in a number of cancer centers across the nation. In this educational session, we will explore the role of U/S, CT, and MRI in HDR prostate brachytherapy. Example workflows and operational details will be shared, and we will discuss how to establish a prostate HDR program in a clinical setting. Learning Objectives: Review prostate HDR techniques based on the imaging modality Discuss the challenges and pitfalls introduced by the three imagebased options for prostate HDR brachytherapy Review the QA process and learn about the development of clinical workflows for these imaging options at different institutions.

  6. Role of brachytherapy in the treatment of localized prostate cancer

    Directory of Open Access Journals (Sweden)

    A. D. Kaprin

    2015-01-01

    Full Text Available The review is devoted to application of brachytherapy for treating the localized prostate cancer (PC. Statistics for incidence and detectability of this pathology and its dynamics for recent years are represented. Brief analysis of other methods which are conveniently used for treatment of PC, such as radical prostatectomy and external-beam radiotherapy, was performed. Advantages and disadvantages of these methods have been discussed. Brief history about the development of brachytherapy from first experience to wide-spread use in clinical practice is reported. The detailed review of series of large trials from Russia and other countries for efficiency and safety of brachytherapy in patients with prostate cancer for recent 15 years is also represented. Two types of brachytherapy in current clinical oncology i.e. low-dose technique with permanent implantation of microsources and high-dose temporary isotope implantation, specifics of its application in different groups of patients have been described. The procedure of brachytherapy and its three main steps i.e. planning, implantation and control assessment after implantation have been characterized in details. The conclusion about benefits of using of brachytherapy in the treatment of prostate cancer as minimally invasive and efficient method was made. 

  7. Intravaginal lactic Acid bacteria modulated local and systemic immune responses and lowered the incidence of uterine infections in periparturient dairy cows.

    Directory of Open Access Journals (Sweden)

    Qilan Deng

    Full Text Available The objective of this investigation was to evaluate whether intravaginal infusion of a lactic acid bacteria (LAB cocktail around parturition could influence the immune response, incidence rate of uterine infections, and the overall health status of periparturient dairy cows. One hundred pregnant Holstein dairy cows were assigned to 1 of the 3 experimental groups as follows: 1 one dose of LAB on wk -2 and -1, and one dose of carrier (sterile skim milk on wk +1 relative to the expected day of parturition (TRT1; 2 one dose of LAB on wk -2, -1, and +1 (TRT2, and 3 one dose of carrier on wk -2, -1, and +1 (CTR. The LAB were a lyophilized culture mixture composed of Lactobacillus sakei FUA3089, Pediococcus acidilactici FUA3138, and Pediococcus acidilactici FUA3140 with a cell count of 108-109 cfu/dose. Blood samples and vaginal mucus were collected once a week from wk -2 to +3 and analyzed for content of serum total immunoglobulin G (IgG, lipopolysaccharide-binding protein (LBP, serum amyloid A (SAA, haptoglobin (Hp, tumor necrosis factor (TNF, interleukin (IL-1, IL-6, and vaginal mucus secretory IgA (sIgA. Clinical observations including rectal temperature, vaginal discharges, retained placenta, displaced abomasum, and laminitis were monitored from wk -2 to +8 relative to calving. Results showed that intravaginal LAB lowered the incidence of metritis and total uterine infections. Intravaginal LAB also were associated with lower concentrations of systemic LBP, an overall tendency for lower SAA, and greater vaginal mucus sIgA. No differences were observed for serum concentrations of Hp, TNF, IL-1, IL-6 and total IgG among the treatment groups. Administration with LAB had no effect on the incidence rates of other transition cow diseases. Overall intravaginal LAB lowered uterine infections and improved local and systemic immune responses in the treated transition dairy cows.

  8. Unexpected Inflammatory Effects of Intravaginal Gels (Universal Placebo Gel and Nonoxynol-9 on the Upper Female Reproductive Tract: A Randomized Crossover Study.

    Directory of Open Access Journals (Sweden)

    Karen Smith-McCune

    Full Text Available Intravaginal anti-HIV microbicides could provide women with a self-controlled means for HIV prevention, but results from clinical trials have been largely disappointing. We postulated that unrecognized effects of intravaginal gels on the upper female reproductive tract might contribute to the lower-than-expected efficacy of HIV microbicides. Our objective was to study the effects of intravaginal gels on the immune microenvironment of the cervix and uterus. In this randomized crossover study, 27 healthy female volunteers used a nightly application of intravaginal nonoxynol-9 (N9 gel as a "failed" microbicide or the universal placebo gel (UPG as a "safe" gel (intervention cycles, or nothing (control cycle from the end of menses to the mid-luteal phase. At a specific time-point following ovulation, all participants underwent sample collection for measurements of T-cell phenotypes, gene expression, and cytokine/chemokine protein concentrations from 3 anatomic sites above the vagina: the cervical transformation zone, the endocervix and the endometrium. We used hierarchical statistical models to estimate mean (95% CI intervention effects, for N9 and UPG relative to control. Exposure to N9 gel and UPG generated a common "harm signal" that included transcriptional up-regulation of inflammatory genes chemokine (C-C motif ligand 20 (macrophage inflammatory factor-3alpha and interleukin 8 in the cervix, decreased protein concentrations of secretory leukocyte protease inhibitor, and transcriptional up-regulation of inflammatory mediators glycodelin-A and osteopontin in the endometrium. These results need to be replicated with a larger sample, but underscore the need to consider the effects of microbicide agents and gel excipients on the upper female reproductive tract in studies of vaginal microbicides.

  9. Concentrations of Dapivirine in the Rhesus Macaque and Rabbit following Once Daily Intravaginal Administration of a Gel Formulation of [14C]Dapivirine for 7 Days▿

    OpenAIRE

    Nuttall, Jeremy P.; Thake, Daryl C.; Lewis, Mark G.; Ferkany, John W.; Romano, Joseph W.; Mitchnick, Mark A.

    2007-01-01

    Dapivirine is a nonnucleoside reverse transcriptase inhibitor being developed as a topical microbicide for the prevention of human immunodeficiency virus infection. The distribution of radioactivity and drug in plasma and in vaginal, cervical, and draining lymph node tissues was investigated after daily application of a vaginal gel formulation of [14C]dapivirine to rhesus macaques. This was preceded by a preliminary study with rabbits. Following the intravaginal administration of [14C]dapivir...

  10. Miniature X-ray Tube for Electric Brachytherapy using Carbon Nanotube Field Emitter

    International Nuclear Information System (INIS)

    Heo, Sung Hwan; Kim, Hyun Jin; Ha, Jun Mok; Cho, Sung Oh

    2011-01-01

    An electric brachytherapy using a miniature x-ray tube has a major advantage to reduce the x-ray exposure of human body during the cancer radiation therapy by optimal positioning of x-ray radiation source and treatment objectives. In the view of a smaller electronic x-ray source, the CNT field emitter based xray tube can be more minimized than thermionic filament emitter based one because of a simple power supplier connection of cold field emission in diode type as well as a higher electron emission brightness of CNT. This abstract is for introducing the design of a prototype CNT field emitter based miniature x-ray tube. We have vacuum sealed CNT miniature x-ray tube with 7∼10 mm diameter, and characteristics of electron emission and x-ray transportation using MCNP5 code are surveyed

  11. Electronics

    Science.gov (United States)

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  12. Overview of brachytherapy resources in Europe: A survey of patterns of care study for brachytherapy in Europe

    International Nuclear Information System (INIS)

    Guedea, Ferran; Ellison, Tracey; Venselaar, Jack; Borras, Josep Maria; Hoskin, Peter; Poetter, Richard; Heeren, Germaine; Nisin, Roselinne; Francois, Guy; Mazeron, Jean Jacques; Limbergen, Erik Van; Ventura, Montserrat; Taillet, Michel; Cottier, Brian

    2007-01-01

    Background and purpose: The Patterns of Care for Brachytherapy in Europe (PCBE) study is aimed at establishing a detailed information system on brachytherapy throughout Europe. Materials and methods: The questionnaire was web-based and the analysis used data from each radiotherapy department with brachytherapy. There were three groups: Group I with 19 countries (15 initial European Community (EC) countries plus Iceland, Monaco, Norway and Switzerland -EC+4-), Group II with 10 countries (New European Community countries -NEC-) and Group III with 14 countries (Other European Countries -OEC-). Results: In the European area there are 36 of 43 countries (85%) which achieved data collection from at least 50% of centres, and were included in the analysis. The tumour site that had the largest number of treated patients was gynaecological tumours. Several variations have been found in the mean number of patients treated per consultant radiation oncologist and physicist; and in the proportion of brachytherapy patients with gynaecology, prostate and breast tumours, by country and by European area. The provided data showed that the average number of brachytherapy patients per centre increased by 10% between 1997 and 2002. Conclusions: A European wide evaluation of brachytherapy practice using a web-based questionnaire is feasible and that there is considerable variation in both patterns of practice and available resources

  13. Interstitial brachytherapy in carcinoma of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, A.J.; Ghosh, S.; Bhalavat, R.L. [Tata Memorial Hospital, Mumbai (India). Dept. of Radiation Oncology; Kulkarni, J.N. [Tata Memorial Hospital, Mumbai (India). Dept. of Surgery; Sequeira, B.V.E. [Tata Memorial Hospital, Mumbai (India). Dept. of Medical Physics

    1999-01-01

    Aim: Keeping in line with the increasing emphasis on organ preservation, we at the Tata Memorial Hospital have evaluated the role of Ir-192 interstitial implant as regards local control, functional and cosmetic outcome in early as well as locally recurrent carcinoma of the distal penis. Patients and Methods: From October 1988 to December 1996, 23 patients with histopathologically proven cancer of the penis were treated with radical radiation therapy using Ir-192 temporary interstitial implant. Our patients were in the age group of 20 to 60 years. The primary lesions were T1 and 7, T2 in 7 and recurrent in 9 patients. Only 7 patients had palpable groin nodes at presentation, all of which were pathologically negative. The median dose of implant was 50 Gy (range 40 to 60 Gy), using the LDR afterloading system and the Paris system of implant rules for dosimetry. Follow-up ranged from 4 to 117 months (median 24 months). Results: At last follow-up 18 of the 23 patients remained locally controlled with implant alone. Three patients failed only locally, 2 locoregionally and 1 only at the groin. Of the 5 patients who failed locally, 4 were successfully salvaged with partial penectomy and remained controlled when last seen. Local control with implant alone at 8 years was 70% by life table analysis. The patients had excellent functional and cosmetic outcome. We did not record any case of skin or softtissue necrosis. Only 2 patients developed meatal stenosis, both of which were treated endoscopically. Conclusion: Our results lead us to interpret that interstitial brachytherapy with Ir-192 offers excellent local control rates with preservation of organ and function. Penectomy can be reserved as a means for effective salvage. (orig.) [Deutsch] Ziel: Das Prinzip des Organerhalts gewinnt in der Onkologie zunehmend an Bedeutung. Ziel dieser Untersuchung war es, die Rolle der interstitiellen Brachytherapie mit Ir-192 zur Behandlung des fruehen und rezidivierten Peniskarzinoms zu

  14. An overview of interstitial brachytherapy and hyperthermia

    International Nuclear Information System (INIS)

    Brandt, B.B.; Harney, J.

    1989-01-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references

  15. Human error in remote Afterloading Brachytherapy

    International Nuclear Information System (INIS)

    Quinn, M.L.; Callan, J.; Schoenfeld, I.; Serig, D.

    1994-01-01

    Remote Afterloading Brachytherapy (RAB) is a medical process used in the treatment of cancer. RAB uses a computer-controlled device to remotely insert and remove radioactive sources close to a target (or tumor) in the body. Some RAB problems affecting the radiation dose to the patient have been reported and attributed to human error. To determine the root cause of human error in the RAB system, a human factors team visited 23 RAB treatment sites in the US. The team observed RAB treatment planning and delivery, interviewed RAB personnel, and performed walk-throughs, during which staff demonstrated the procedures and practices used in performing RAB tasks. Factors leading to human error in the RAB system were identified. The impact of those factors on the performance of RAB was then evaluated and prioritized in terms of safety significance. Finally, the project identified and evaluated alternative approaches for resolving the safety significant problems related to human error

  16. Calibration of Photon Sources for Brachytherapy

    Science.gov (United States)

    Rijnders, Alex

    Source calibration has to be considered an essential part of the quality assurance program in a brachytherapy department. Not only it will ensure that the source strength value used for dose calculation agrees within some predetermined limits to the value stated on the source certificate, but also it will ensure traceability to international standards. At present calibration is most often still given in terms of reference air kerma rate, although calibration in terms of absorbed dose to water would be closer to the users interest. It can be expected that in a near future several standard laboratories will be able to offer this latter service, and dosimetry protocols will have to be adapted in this way. In-air measurement using ionization chambers (e.g. a Baldwin—Farmer ionization chamber for 192Ir high dose rate HDR or pulsed dose rate PDR sources) is still considered the method of choice for high energy source calibration, but because of their ease of use and reliability well type chambers are becoming more popular and are nowadays often recommended as the standard equipment. For low energy sources well type chambers are in practice the only equipment available for calibration. Care should be taken that the chamber is calibrated at the standard laboratory for the same source type and model as used in the clinic, and using the same measurement conditions and setup. Several standard laboratories have difficulties to provide these calibration facilities, especially for the low energy seed sources (125I and 103Pd). Should a user not be able to obtain properly calibrated equipment to verify the brachytherapy sources used in his department, then at least for sources that are replaced on a regular basis, a consistency check program should be set up to ensure a minimal level of quality control before these sources are used for patient treatment.

  17. Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Fox, C. D.; Kron, T.; Leahy, M.; Duchesne, G.; Williams, S.; Tai, K. H.; Haworth, A.; Herschtal, A.; Foroudi, F. [Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Nursing Service, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Department of Radiation Oncology, Peter MacCallum Cancer Centre and University of Melbourne, Melbourne, Victoria 3002 (Australia); Department of Physical Sciences, Peter MacCallum Cancer Centre and Royal Melbourne Insititute of Technology, Melbourne, Victoria 3000 (Australia); Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Victoria 3002 (Australia); Department of Radiation Oncology, Peter MacCallum Cancer Centre and University of Melbourne, Melbourne, Victoria 3010 (Australia)

    2011-11-15

    Purpose: To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. Methods: An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. Results: The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. Conclusions: It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

  18. Interfraction patient motion and implant displacement in prostate high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Fox, C. D.; Kron, T.; Leahy, M.; Duchesne, G.; Williams, S.; Tai, K. H.; Haworth, A.; Herschtal, A.; Foroudi, F.

    2011-01-01

    Purpose: To quantify movement of prostate cancer patients undergoing treatment, using an in-house developed motion sensor in order to determine a relationship between patient movement and high dose rate (HDR) brachytherapy implant displacement. Methods: An electronic motion sensor was developed based on a three axis accelerometer. HDR brachytherapy treatment for prostate is delivered at this institution in two fractions 24 h apart and 22 patients were monitored for movement over the interval between fractions. The motion sensors functioned as inclinometers, monitoring inclination of both thighs, and the inclination and roll of the abdomen. The implanted HDR brachytherapy catheter set was assessed for displacement relative to fiducial markers in the prostate. Angle measurements and angle differences over a 2 s time base were binned, and the standard deviations of the resulting frequency distributions used as a metric for patient motion in each monitored axis. These parameters were correlated to measured catheter displacement using regression modeling. Results: The mean implant displacement was 12.6 mm in the caudal direction. A mean of 19.95 h data was recorded for the patient cohort. Patients generally moved through a limited range of angles with a mean of the exception of two patients who spent in excess of 2 h lying on their side. When tested for a relationship between movement in any of the four monitored axes and the implant displacement, none was significant. Conclusions: It is not likely that patient movement influences HDR prostate implant displacement. There may be benefits to patient comfort if nursing protocols were relaxed to allow patients greater freedom to move while the implant is in situ.

  19. The use of tetrahedral mesh geometries in Monte Carlo simulation of applicator based brachytherapy dose distributions

    International Nuclear Information System (INIS)

    Fonseca, Gabriel Paiva; Yoriyaz, Hélio; Landry, Guillaume; White, Shane; Reniers, Brigitte; Verhaegen, Frank; D’Amours, Michel; Beaulieu, Luc

    2014-01-01

    Accounting for brachytherapy applicator attenuation is part of the recommendations from the recent report of AAPM Task Group 186. To do so, model based dose calculation algorithms require accurate modelling of the applicator geometry. This can be non-trivial in the case of irregularly shaped applicators such as the Fletcher Williamson gynaecological applicator or balloon applicators with possibly irregular shapes employed in accelerated partial breast irradiation (APBI) performed using electronic brachytherapy sources (EBS). While many of these applicators can be modelled using constructive solid geometry (CSG), the latter may be difficult and time-consuming. Alternatively, these complex geometries can be modelled using tessellated geometries such as tetrahedral meshes (mesh geometries (MG)). Recent versions of Monte Carlo (MC) codes Geant4 and MCNP6 allow for the use of MG. The goal of this work was to model a series of applicators relevant to brachytherapy using MG. Applicators designed for 192 Ir sources and 50 kV EBS were studied; a shielded vaginal applicator, a shielded Fletcher Williamson applicator and an APBI balloon applicator. All applicators were modelled in Geant4 and MCNP6 using MG and CSG for dose calculations. CSG derived dose distributions were considered as reference and used to validate MG models by comparing dose distribution ratios. In general agreement within 1% for the dose calculations was observed for all applicators between MG and CSG and between codes when considering volumes inside the 25% isodose surface. When compared to CSG, MG required longer computation times by a factor of at least 2 for MC simulations using the same code. MCNP6 calculation times were more than ten times shorter than Geant4 in some cases. In conclusion we presented methods allowing for high fidelity modelling with results equivalent to CSG. To the best of our knowledge MG offers the most accurate representation of an irregular APBI balloon applicator. (paper)

  20. Methods for prostate stabilization during transperineal LDR brachytherapy

    International Nuclear Information System (INIS)

    Podder, Tarun; Yu Yan; Sherman, Jason; Rubens, Deborah; Strang, John; Messing, Edward; Ng, Wan-Sing

    2008-01-01

    In traditional prostate brachytherapy procedures for a low-dose-rate (LDR) radiation seed implant, stabilizing needles are first inserted to provide some rigidity and support to the prostate. Ideally this will provide better seed placement and an overall improved treatment. However, there is much speculation regarding the effectiveness of using regular brachytherapy needles as stabilizers. In this study, we explored the efficacy of two types of needle geometries (regular brachytherapy needle and hooked needle) and several clinically feasible configurations of the stabilization needles. To understand and assess the prostate movement during seed implantation, we collected in vivo data from patients during actual brachytherapy procedures. In vitro experimentation with tissue-equivalent phantoms allowed us to further understand the mechanics behind prostate stabilization. We observed superior stabilization with the hooked needles compared to the regular brachytherapy needles (more than 40% in bilateral parallel needle configuration). Prostate movement was also reduced significantly when regular brachytherapy needles were in an angulated configuration as compared to the parallel configuration (more than 60%). When the hooked needles were angulated for stabilization, further reduction in prostate displacement was observed. In general, for convenience of dosimetric planning and to avoid needle collision, all needles are desired to be in a parallel configuration. In this configuration, hooked needles provide improved stabilization of the prostate. On the other hand, both regular and hooked needles appear to be equally effective in reducing prostate movement when they are in angulated configurations, which will be useful in seed implantation using a robotic system. We have developed nonlinear spring-damper model for the prostate movement which can be used for adapting dosimetric planning during brachytherapy as well as for developing more realistic haptic devices and

  1. Methods for prostate stabilization during transperineal LDR brachytherapy.

    Science.gov (United States)

    Podder, Tarun; Sherman, Jason; Rubens, Deborah; Messing, Edward; Strang, John; Ng, Wan-Sing; Yu, Yan

    2008-03-21

    In traditional prostate brachytherapy procedures for a low-dose-rate (LDR) radiation seed implant, stabilizing needles are first inserted to provide some rigidity and support to the prostate. Ideally this will provide better seed placement and an overall improved treatment. However, there is much speculation regarding the effectiveness of using regular brachytherapy needles as stabilizers. In this study, we explored the efficacy of two types of needle geometries (regular brachytherapy needle and hooked needle) and several clinically feasible configurations of the stabilization needles. To understand and assess the prostate movement during seed implantation, we collected in vivo data from patients during actual brachytherapy procedures. In vitro experimentation with tissue-equivalent phantoms allowed us to further understand the mechanics behind prostate stabilization. We observed superior stabilization with the hooked needles compared to the regular brachytherapy needles (more than 40% in bilateral parallel needle configuration). Prostate movement was also reduced significantly when regular brachytherapy needles were in an angulated configuration as compared to the parallel configuration (more than 60%). When the hooked needles were angulated for stabilization, further reduction in prostate displacement was observed. In general, for convenience of dosimetric planning and to avoid needle collision, all needles are desired to be in a parallel configuration. In this configuration, hooked needles provide improved stabilization of the prostate. On the other hand, both regular and hooked needles appear to be equally effective in reducing prostate movement when they are in angulated configurations, which will be useful in seed implantation using a robotic system. We have developed nonlinear spring-damper model for the prostate movement which can be used for adapting dosimetric planning during brachytherapy as well as for developing more realistic haptic devices and

  2. Safety and pharmacokinetics of dapivirine delivery from matrix and reservoir intravaginal rings to HIV-negative women.

    Science.gov (United States)

    Nel, Annalene; Smythe, Shanique; Young, Katherine; Malcolm, Karl; McCoy, Clare; Rosenberg, Zeda; Romano, Joseph

    2009-08-01

    Vaginal microbicides for the prevention of HIV transmission may be an important option for protecting women from infection. Incorporation of dapivirine, a lead candidate nonnucleoside reverse transcriptase inhibitor, into intravaginal rings (IVRs) for sustained mucosal delivery may increase microbicide product adherence and efficacy compared with conventional vaginal formulations. Twenty-four healthy HIV-negative women 18-35 years of age were randomly assigned (1:1:1) to dapivirine matrix IVR, dapivirine reservoir IVR, or placebo IVR. Dapivirine concentrations were measured in plasma and vaginal fluid samples collected at sequential time points over the 33-day study period (28 days of IVR use, 5 days of follow-up). Safety was assessed by pelvic/colposcopic examinations, clinical laboratory tests, and adverse events. Both IVR types were safe and well tolerated with similar adverse events observed in the placebo and dapivirine groups. Dapivirine from both IVR types was successfully distributed throughout the lower genital tract at concentrations over 4 logs greater than the EC50 against wild-type HIV-1 (LAI) in MT4 cells. Maximum concentration (Cmax) and area under the concentration-time curve (AUC) values were significantly higher with the matrix than reservoir IVR. Mean plasma concentrations of dapivirine were <2 ng/mL. These findings suggest that IVR delivery of microbicides is a viable option meriting further study.

  3. Qualitative and quantitative intravaginal targeting: key to anti-HIV-1 microbicide delivery from test tube to in vivo success.

    Science.gov (United States)

    Pillay, Viness; Mashingaidze, Felix; Choonara, Yahya E; Du Toit, Lisa C; Buchmann, Eckhart; Maharaj, Vinesh; Ndesendo, Valence M K; Kumar, Pradeep

    2012-06-01

    The past decade has seen several effective anti-HIV-1 agent discoveries, yet microbicides continue to disappoint clinically. Our review expounds the view that unsatisfactory microbicide failures may be a result of inefficient delivery systems employed. We hereby propose a thorough scientific qualitative and quantitative investigation of important aspects involved in HIV-1 transmission as a prerequisite for microbicide delivery. Intravaginal targeting of HIV-1 increases the chances of microbicide success, wherein vaginal microenvironmental factors including pH should be maintained at HIV-1 prohibitive acidic levels simultaneously to ward off other sexually transmitted diseases, which compromise vaginal epithelial barrier properties. Furthermore, choice of receptors to target both on HIV-1 and on target cells is vital in deterring transmission. Appropriate modeling of virus-target cell interactions as well as targeting early stages of the HIV-1 infection accompanied by computation and delivery of appropriate microbicide quantities could revolutionize microbicide research, ultimately delivering a female-controlled HIV-1 prevention modality appropriately. Copyright © 2012 Wiley Periodicals, Inc.

  4. Poster - 09: A MATLAB-based Program for Automated Quality Assurance of a Prostate Brachytherapy Ultrasound System

    Energy Technology Data Exchange (ETDEWEB)

    Poon, Justin; Sabondjian, Eric; Sankreacha, Raxa [University of British Columbia, Dept. of Physics and Astronomy, Vancouver, BC (Canada); Trillium Health Partners – Credit Valley Hospital, Peel Regional Cancer Centre, Mississauga, ON, Trillium Health Partners – Credit Valley Hospital, Peel Regional Cancer Centre, Mississauga, ON, Trillium Health Partners – Credit Valley Hospital, Peel Regional Cancer Centre, Mississauga, ON (Canada); University of Toronto, Dept. of Radiation Oncology, Toronto, ON (Canada)

    2016-08-15

    Purpose: A robust Quality Assurance (QA) program is essential for prostate brachytherapy ultrasound systems due to the importance of imaging accuracy during treatment and planning. Task Group 128 of the American Association of Physicists in Medicine has recommended a set of QA tests covering grayscale visibility, depth of penetration, axial and lateral resolution, distance measurement, area measurement, volume measurement, and template/electronic grid alignment. Making manual measurements on the ultrasound system can be slow and inaccurate, so a MATLAB program was developed for automation of the described tests. Methods: Test images were acquired using a BK Medical Flex Focus 400 ultrasound scanner and 8848 transducer with the CIRS Brachytherapy QA Phantom – Model 045A. For each test, the program automatically segments the inputted image(s), makes the appropriate measurements, and indicates if the test passed or failed. The program was tested by analyzing two sets of images, where the measurements from the first set were used as baseline values. Results: The program successfully analyzed the images for each test and determined if any action limits were exceeded. All tests passed – the measurements made by the program were consistent and met the requirements outlined by Task Group 128. Conclusions: The MATLAB program we have developed can be used for automated QA of an ultrasound system for prostate brachytherapy. The GUI provides a user-friendly way to analyze images without the need for any manual measurement, potentially removing intra- and inter-user variability for more consistent results.

  5. Poster - 09: A MATLAB-based Program for Automated Quality Assurance of a Prostate Brachytherapy Ultrasound System

    International Nuclear Information System (INIS)

    Poon, Justin; Sabondjian, Eric; Sankreacha, Raxa

    2016-01-01

    Purpose: A robust Quality Assurance (QA) program is essential for prostate brachytherapy ultrasound systems due to the importance of imaging accuracy during treatment and planning. Task Group 128 of the American Association of Physicists in Medicine has recommended a set of QA tests covering grayscale visibility, depth of penetration, axial and lateral resolution, distance measurement, area measurement, volume measurement, and template/electronic grid alignment. Making manual measurements on the ultrasound system can be slow and inaccurate, so a MATLAB program was developed for automation of the described tests. Methods: Test images were acquired using a BK Medical Flex Focus 400 ultrasound scanner and 8848 transducer with the CIRS Brachytherapy QA Phantom – Model 045A. For each test, the program automatically segments the inputted image(s), makes the appropriate measurements, and indicates if the test passed or failed. The program was tested by analyzing two sets of images, where the measurements from the first set were used as baseline values. Results: The program successfully analyzed the images for each test and determined if any action limits were exceeded. All tests passed – the measurements made by the program were consistent and met the requirements outlined by Task Group 128. Conclusions: The MATLAB program we have developed can be used for automated QA of an ultrasound system for prostate brachytherapy. The GUI provides a user-friendly way to analyze images without the need for any manual measurement, potentially removing intra- and inter-user variability for more consistent results.

  6. The American brachytherapy society survey of brachytherapy practice for carcinoma of the cervix in the United States.

    Science.gov (United States)

    Nag, S; Orton, C; Young, D; Erickson, B

    1999-04-01

    The purpose of this study was to survey the brachytherapy practice for cervical cancer in the United States. The Clinical Research Committee of the American Brachytherapy Society (ABS) performed a retrospective survey of individual physicians of the ABS and American Society of Therapeutic Radiologists and Oncologists regarding the details of the brachytherapy techniques they personally used in the treatment of cervical cancer patients for the year 1995. The replies (some of which may have been an estimate only) were tabulated. The scope of this survey did not allow us to verify the data by chart audits. A total of about 3500 questionnaires were mailed out; 521 responses were received. Of these responders, 206 (40%) did not perform any brachytherapy for carcinoma of the cervix in 1995. Of the other 315 responders reporting a total of 4892 patients treated in 1995, 88% used low dose rate (LDR) while 24% used high dose rate (HDR). There was a wide variation in the doses used. For LDR treatments, the median total external beam radiation therapy (EBRT) dose was 45 and 50 Gy and the LDR dose was 42 and 45 Gy for early and advanced cancers, respectively. For HDR treatments, the median EBRT dose was 48 and 50 Gy and the median HDR dose was 29 and 30 Gy for early and advanced cancers, respectively. The median dose per fraction was 6 Gy for a median of five fractions. Interstitial brachytherapy was used as a component of the treatment in 6% of the patients by 21% of responders. Very few responders treated with pulsed or medium dose rates. This retrospective survey showed the current brachytherapy practice pattern in the treatment of cervical cancer in the United States and can serve as a basis for future prospective national brachytherapy data registry. There was wide variation in the practice pattern, emphasizing the urgent need for consensus on these issues. Copyright 1999 Academic Press.

  7. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    International Nuclear Information System (INIS)

    Smith, Grace L.; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A.; Smith, Benjamin D.

    2015-01-01

    Purpose: To directly compare (1) radiation treatment utilization patterns; (2) risks of subsequent mastectomy; and (3) costs of radiation treatment in patients treated with brachytherapy versus whole-breast irradiation (WBI), in a national, contemporary cohort of women with incident breast cancer, aged 64 years and younger. Methods and Materials: Using MarketScan health care claims data, we identified 45,884 invasive breast cancer patients (aged 18-64 years), treated from 2003 to 2010 with lumpectomy, followed by brachytherapy (n=3134) or whole-breast irradiation (n=42,750). We stratified patients into risk groups according to age (Age<50 vs Age≥50) and endocrine therapy status (Endocrine− vs Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy versus WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results: Brachytherapy utilization increased from 2003 to 2010: in patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 versus 32% of WBI patients (P<.001); whereas 41% of brachytherapy patients were Endocrine–versus 44% of WBI patients (P=.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs 9.0% after WBI (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.37-3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs 4.9%; HR 1.76, 95% CI 1.26-2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs 4.5%; HR 1.18, 95% CI 0.61-2.31); Endocrine+/Age≥50 (4.2% vs 2

  8. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Grace L. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Huo, Jinhai [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hunt, Kelly K. [Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D., E-mail: bsmith3@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-09-01

    Purpose: To directly compare (1) radiation treatment utilization patterns; (2) risks of subsequent mastectomy; and (3) costs of radiation treatment in patients treated with brachytherapy versus whole-breast irradiation (WBI), in a national, contemporary cohort of women with incident breast cancer, aged 64 years and younger. Methods and Materials: Using MarketScan health care claims data, we identified 45,884 invasive breast cancer patients (aged 18-64 years), treated from 2003 to 2010 with lumpectomy, followed by brachytherapy (n=3134) or whole-breast irradiation (n=42,750). We stratified patients into risk groups according to age (Age<50 vs Age≥50) and endocrine therapy status (Endocrine− vs Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy versus WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results: Brachytherapy utilization increased from 2003 to 2010: in patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 versus 32% of WBI patients (P<.001); whereas 41% of brachytherapy patients were Endocrine–versus 44% of WBI patients (P=.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs 9.0% after WBI (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.37-3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs 4.9%; HR 1.76, 95% CI 1.26-2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs 4.5%; HR 1.18, 95% CI 0.61-2.31); Endocrine+/Age≥50 (4.2% vs 2

  9. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Bloemen-Van Gurp, Esther; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, de l' Universite Laval, CHUQ, Pavillon L' Hotel-Dieu de Quebec, Quebec G1R 2J6 (Canada) and Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec G1K 7P4 (Canada); Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands) and Medical Physics Unit, McGill University, Montreal General Hospital, Montreal, Quebec H3G 1A4 (Canada)

    2010-10-15

    Purpose: The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: {sup 125}I, {sup 103}Pd, {sup 131}Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D{sub w,m} as opposed to dose to a small mass of medium in medium D{sub m,m}. Methods: Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using {sup 125}I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D{sub 90} values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using {sup 103}Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D{sub 90} values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results: Results from simulation (1) show that variations

  10. Construction balance analysis of dose rate medium brachytherapy TDS

    International Nuclear Information System (INIS)

    Sandi Parapak

    2011-01-01

    One of the most important part of brachytherapy instrument design activities is analyze by determining the centroid point of construction in order to maintain the balance of brachytherapy instrument, either during operation as well as when transported. Operation of brachytherapy is not only done in one place so it is necessary to balance the analysis of the forces at the time did not move, moved on the horizontal floor and sloping floor. Calculation approach who is done to calculate the weight of mechanical components on each module, and then calculate the centroid of each module, for the balance of forces analysis performed with the assumption at the time of brachytherapy in the position of not moving on a horizontal floor, moved from a place to another on the horizontal floor and on the floor with sloping angle 30°. Base on the results of this analysis are expected to balance the four wheels can move without slipping at the time of decline or incline. Also, results of analysis can be used in designing a mobile construction brachytherapy taking into consideration the aesthetic ideal, easy to operate, ensure the safety of equipment, operator and patient. (author)

  11. High dose rate brachytherapy for the palliation of malignant dysphagia

    International Nuclear Information System (INIS)

    Homs, Marjolein Y.V.; Eijkenboom, Wilhelmina M.H.; Coen, Veronique L.M.A.; Haringsma, Jelle; Blankenstein, Mark van; Kuipers, Ernst J.; Siersema, Peter D.

    2003-01-01

    Background and purpose: High dose rate (HDR) brachytherapy is a commonly used palliative treatment for esophageal carcinoma. We evaluated the outcome of HDR brachytherapy in patients with malignant dysphagia. Material and methods: A retrospective analysis over a 10-year period was performed of 149 patients treated with HDR brachytherapy, administered in one or two sessions, at a median dose of 15 Gy. Patients were evaluated for functional outcome, complications, recurrent dysphagia, and survival. Results: At 6 weeks after HDR brachytherapy, dysphagia scores had improved from a median of 3 to 2 (n=104; P<0.001), however, dysphagia had not improved in 51 (49%) patients. Procedure-related complications occurred in seven (5%) patients. Late complications, including fistula formation or bleeding, occurred in 11 (7%) patients. Twelve (8%) patients experienced minor retrosternal pain. Median survival of the patients was 160 days with a 1-year survival rate of 15%. Procedure-related mortality was 2%. At follow-up, 55 (37%) patients experienced recurrent dysphagia. In 34 (23%) patients a metal stent was placed to relieve persistent or recurrent dysphagia. Conclusion: HDR brachytherapy is a moderately effective treatment for the palliation of malignant dysphagia. The incidence of early major complications is low, however, persistent and recurrent dysphagia occur frequently, and require often additional treatment

  12. Brachytherapy - not pulsed and low rate brachytherapy. Medical radiation protection - ED 4248

    International Nuclear Information System (INIS)

    2008-06-01

    After an indication of authorizations required to perform brachytherapy, this sheet indicates the concerned personnel, indicates the different treatment steps, briefly describes the risk related to ionizing radiations, indicates the various aspects of risk assessment and of determination of exposure levels (definition of controlled and monitored areas, personnel classification, possible methods for dose monitoring), presents the strategy for risk management (rules regarding risk reduction, technical measures regarding the installation, individual technical measures, training and information, prevention and medical monitoring) and how this risk management can be assessed

  13. A survey of current clinical practice in permanent and temporary prostate brachytherapy: 2010 update.

    Science.gov (United States)

    Buyyounouski, Mark K; Davis, Brian J; Prestidge, Bradley R; Shanahan, Thomas G; Stock, Richard G; Grimm, Peter D; Demanes, D Jeffrey; Zaider, Marco; Horwitz, Eric M

    2012-01-01

    To help establish patterns of care and standards of care of interstitial permanent low-dose-rate (LDR) and temporary high-dose-rate brachytherapy for prostate cancer and to compare the results with a similar 1998 American Brachytherapy Society (ABS) survey. A comprehensive questionnaire intended to survey specific details of current clinical brachytherapy practice was provided to the participants of the seventh ABS Prostate Brachytherapy School. Responses were tabulated and descriptive statistics are reported. Sixty-five brachytherapy practitioners responded to the survey. Eighty-nine percent (89%) of respondents performed LDR and 49% perform high-dose-rate brachytherapy. The median number of years of experience for LDR brachytherapists increased from 5 to 10 years over the course of the 12 years since the preceding survey. Compared with the first ABS, a smaller proportion of respondents received formal brachytherapy residency training (43% vs. 56%) or formal "hands-on" brachytherapy training (15% vs. 63%). There has been a marked decline in the utilization of the Mick applicator (Mick Radio-Nuclear Instruments, Inc., Mount Vernon, NY, USA) (60% vs. 28%) and an increase in the use of stranded seeds (40% vs. 11%). Compliance with postimplant dosimetry was higher in the 2010 survey. This survey does suggest an evolution in the practice of LDR brachytherapy since 1998 and aids in identifying aspects that require further progress or investigation. ABS guidelines and other practice recommendations appear to impact the practice of brachytherapy. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  14. Radiological protection of patients in brachytherapy

    International Nuclear Information System (INIS)

    Sacc, Ricardo; Herrero, Flavia

    2008-01-01

    Full text: The prefix 'brachy' means short-range, so brachytherapy is the administration of radiation therapy using small radioactive sources in the form of needles, tubes, wires or seeds, which are placed within the tumor -interstitial form- or very near of it, superficially or in an endo-cavity form. This technique, which was limited by the size of the primary tumor, has the advantage, that the radiation, can be adjusted to the size and shape of the tumor volume and the radioisotope used, - short range -, is selected with the criteria of getting the dose in the organs at risk, as low as possible, making what it is known as conformal radiotherapy. Radioactive sources may be permanent or temporary implants. The application of radioactive material, can be manually or automatically. In the first case, a major breakthrough from the radioprotection point of view, was the use of afterloading devices, methodology highly recommended to reduce the radiation exposure to staff. With the development of technology, remotely controlled afterloading devices were introduced, which in addition to complying with the above requirement, allow the source to move in different positions along catheters housed in one or more channels, making therapeutic brachytherapy treatments in tumor volumes possible, that due to its length, decades ago would have been an unthinkable deal. In all cases, sources, which may vary from the 3 mm in length, 125 Iodine or 198 Gold seeds, to extensive wires of 192 Iridium, are encapsulated for two main purposes: preventing leakage of radioactive material and absorption of unwanted radiation, alpha and beta, produced by the radioactive decay. Consequently, it should be highly unlikely that the radioactive material, could be lost or located in the patient, in a different place of the one that was planned. However, history shows us the opposite. Its is known the kind of deterministic effect that radiation is going to produce in the tumor, where the severity of

  15. Standardization of prostate brachytherapy treatment plans

    International Nuclear Information System (INIS)

    Ove, Roger; Wallner, Kent; Badiozamani, Kas; Korjsseon, Tammy; Sutlief, Steven

    2001-01-01

    Purpose: Whereas custom-designed plans are the norm for prostate brachytherapy, the relationship between linear prostate dimensions and volume calls into question the routine need for customized treatment planning. With the goal of streamlining the treatment-planning process, we have compared the treatment margins (TMs) achieved with one standard plan applied to patients with a wide range of prostate volumes. Methods and Materials: Preimplant transrectal ultrasound (TRUS) images of 50 unselected University of Washington patients with T1-T2 cancer and a prostate volume between 20 cc and 50 cc were studied. Patients were arbitrarily grouped into categories of 20-30 cc, 30-40 cc, and 40-50 cc. A standard 19-needle plan was devised for patients in the 30- to 40-cc range, using an arbitrary minimum margin of 5 mm around the gross tumor volume (GTV), making use of inverse planning technology to achieve 100% coverage of the target volume with accentuation of dose at the periphery and sparing of the central region. The idealized plan was applied to each patient's TRUS study. The distances (TMs) between the prostatic edge (GTV) and treated volume (TV) were determined perpendicular to the prostatic margin. Results: Averaged over the entire patient group, the ratio of thickness to width was 1.4, whereas the ratio of length to width was 1.3. These values were fairly constant over the range of volumes, emphasizing that the prostate retains its general shape as volume increases. The idealized standard plan was overlaid on the ultrasound images of the 17 patients in the 30- to 40-cc group and the V100, the percentage of target volume receiving 100% or more of the prescription dose, was 98% or greater for 15 of the 17 patients. The lateral and posterior TMs fell within a narrow range, most being within 2 mm of the idealized 5-mm TM. To estimate whether a 10-cc volume-interval stratification was reasonable, the standard plan generated from the 30- to 40-cc prostate model was

  16. Indications and technical aspects of brachytherapy in breast conserving treatment of breast cancer

    International Nuclear Information System (INIS)

    Erik Van, Limbergen

    2003-01-01

    Improved local control rates have been demonstrated in retrospective studies as well as in randomized trials on brachytherapy with increasing doses to the tumour bed. The higher local control obtained by interstitial breast implants, as compared to external photon or electron beam boosts, have been mainly attributed to the higher doses actually delivered to the tumour bed by these implants for the same nominal dose as compared to external beam radiotherapy (RT). On the other hand, poor cosmesis has also been correlated with radiation dose to the breast skin (radiation telangiectases), and breast tissue (retraction due to fibrosis), the latter depending not only on RT dose but also on the treated boost volume. For this reason, a possible benefit of interstitial implants will only be realized when the gain in local control goes together with minimal cosmetic damage. Therefore, the ballistic advantages of interstitial implants have to be maximally exploited: i.e. the treated volume should be maximally adapted to the target volume, and additional irradiation of the breast skin by the boost technique should be avoided. This paper deals in detail with the technical aspects of breast brachytherapy that seem to be relevant for high quality outcome. (author)

  17. Interstitial rotating shield brachytherapy for prostate cancer

    International Nuclear Information System (INIS)

    Adams, Quentin E.; Xu, Jinghzu; Breitbach, Elizabeth K.; Li, Xing; Rockey, William R.; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.; Enger, Shirin A.

    2014-01-01

    Purpose: To present a novel needle, catheter, and radiation source system for interstitial rotating shield brachytherapy (I-RSBT) of the prostate. I-RSBT is a promising technique for reducing urethra, rectum, and bladder dose relative to conventional interstitial high-dose-rate brachytherapy (HDR-BT). Methods: A wire-mounted 62 GBq 153 Gd source is proposed with an encapsulated diameter of 0.59 mm, active diameter of 0.44 mm, and active length of 10 mm. A concept model I-RSBT needle/catheter pair was constructed using concentric 50 and 75 μm thick nickel-titanium alloy (nitinol) tubes. The needle is 16-gauge (1.651 mm) in outer diameter and the catheter contains a 535 μm thick platinum shield. I-RSBT and conventional HDR-BT treatment plans for a prostate cancer patient were generated based on Monte Carlo dose calculations. In order to minimize urethral dose, urethral dose gradient volumes within 0–5 mm of the urethra surface were allowed to receive doses less than the prescribed dose of 100%. Results: The platinum shield reduced the dose rate on the shielded side of the source at 1 cm off-axis to 6.4% of the dose rate on the unshielded side. For the case considered, for the same minimum dose to the hottest 98% of the clinical target volume (D 98% ), I-RSBT reduced urethral D 0.1cc below that of conventional HDR-BT by 29%, 33%, 38%, and 44% for urethral dose gradient volumes within 0, 1, 3, and 5 mm of the urethra surface, respectively. Percentages are expressed relative to the prescription dose of 100%. For the case considered, for the same urethral dose gradient volumes, rectum D 1cc was reduced by 7%, 6%, 6%, and 6%, respectively, and bladder D 1cc was reduced by 4%, 5%, 5%, and 6%, respectively. Treatment time to deliver 20 Gy with I-RSBT was 154 min with ten 62 GBq 153 Gd sources. Conclusions: For the case considered, the proposed 153 Gd-based I-RSBT system has the potential to lower the urethral dose relative to HDR-BT by 29%–44% if the clinician allows

  18. The needs for brachytherapy source calibrations in the United States

    International Nuclear Information System (INIS)

    Coursey, B.M.; Goodman, L.J.; Hoppes, D.D.; Loevinger, R.; McLaughlin, W.L.; Soares, C.G.; Weaver, J.T.

    1992-01-01

    Brachytherapy sources of beta and gamma radiation ('brachy' is from the Greek, meaning 'near') have a long history of use in interstitial, intracavitary, intraluminal, and ocular radiation therapy. In the past the US national standards for these sources were often specified in activity or milligram radium equivalent. With the introduction of new radionuclide sources to replace radium, source strength calibrations are now expressed as air kerma rate at a meter. In this paper, we review the NIST standards for brachytherapy sources, list some of the common radionuclides and source encapsulations in use in the US radiology community, and describe the latest NIST work, in collaboration with several US medical institutions, on a method of two- and three-dimensional dose mapping of brachytherapy sources using radiochromic films. (orig.)

  19. Effects of brachytherapy on gene expressions of elastin and elastase

    International Nuclear Information System (INIS)

    Li Junming; Zhou Jingqun; Hu Bin; Li Shuguo

    2004-01-01

    Objective: To study the effects of brachytherapy on the gene expressions of elastin and elastase in cultured rat vascular smooth muscle cells (VSMCs). Methods: Rat VSMCs cultured in DMEM containing 10% FBS were irradiated by 60 Co γ-rays at 0, 7, 14, 28 Gy respectively. Then mRNA levels of elastin and elastase were determined by reverse transcription competitive PCR(RT-PCR). Results: Brachytherapy inhibited the expressions of elastase. Elastase mRNA decreased 25.3% and 50.1% in VSMC irradiated with 14, 28 Gy, respectively (P<0.05). The elastin mRNA level increased 80.7% and 102.3% in VSMC irradiated with 14, 25 Gy, respectively (P<0.05). Conclusion: Brachytherapy inhabits the expressions of elastase and increased elastin in VSMC cells

  20. Indication of brachytherapy of prostate with permanent implants

    International Nuclear Information System (INIS)

    Chauveinc, L.; Solignac, S.; Rosenwald, J.C.; Firmin, F.; Cosset, J.M.; Flam, T.; Thiounn, N.

    2002-01-01

    In the last decade, brachytherapy emerged as a particularly appealing new way of treating localized prostate cancer. Recently published 10-12 years biochemical control results appear to be superimposable to the best percentages achieved by surgery or conformal radiotherapy, with a small percentage of complications. This applied to severely patients. Only patients with T1/T2, PSA 60 g, hip mobility limitations, a urinary obstructive syndrome and previous trans-urethral resection lead to difficulties in technical implantation and therefore must be taken into account when discussing brachytherapy. In conclusion, for adequately selected patients, brachytherapy offers a particularly applied alternative to surgery and external radiotherapy, with satisfactory long term biochemical control rates and limited complications. (author)

  1. Algorithms for the process management of sealed source brachytherapy

    International Nuclear Information System (INIS)

    Engler, M.J.; Ulin, K.; Sternick, E.S.

    1996-01-01

    Incidents and misadministrations suggest that brachytherapy may benefit form clarification of the quality management program and other mandates of the US Nuclear Regulatory Commission. To that end, flowcharts of step by step subprocesses were developed and formatted with dedicated software. The overall process was similarly organized in a complex flowchart termed a general process map. Procedural and structural indicators associated with each flowchart and map were critiqued and pre-existing documentation was revised. open-quotes Step-regulation tablesclose quotes were created to refer steps and subprocesses to Nuclear Regulatory Commission rules and recommendations in their sequences of applicability. Brachytherapy algorithms were specified as programmable, recursive processes, including therapeutic dose determination and monitoring doses to the public. These algorithms are embodied in flowcharts and step-regulation tables. A general algorithm is suggested as a template form which other facilities may derive tools to facilitate process management of sealed source brachytherapy. 11 refs., 9 figs., 2 tabs

  2. Dosimetry in intravascular brachytherapy; Calculos dosimetricos em braquiterapia intravascular

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing {sup 32} P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  3. Dosimetry in intravascular brachytherapy; Calculos dosimetricos em braquiterapia intravascular

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing {sup 32} P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  4. Current status of brachytherapy in cancer treatment – short overview

    Directory of Open Access Journals (Sweden)

    Janusz Skowronek

    2017-12-01

    Full Text Available Cancer incidence and mortality depend on a number of factors, including age, socio-economic status and geographical location, and its prevalence is growing around the world. Most of cancer treatments include external beam radiotherapy or brachytherapy. Brachytherapy, a type of radiotherapy with energy from radionuclides inserted directly into the tumor, is increasingly used in cancer treatment. For cervical and skin cancers, it has become a standard therapy for more than 100 years as well as an important part of the treatment guidelines for other malignancies, including head and neck, skin, breast, and prostate cancers. Compared to external beam radiotherapy, brachytherapy has the potential to deliver an ablative radiation dose over a short period of time directly to the altered tissue area with the advantage of a rapid fall-off in dose, and consequently, sparing of adjacent organs. As a result, the patient is able to complete the treatment earlier, and the risks of occurrence of another cancer are lower than in conventional radiotherapy treatment. Brachytherapy has increased its use as a radical or palliative treatment, and become more advanced with the spread of pulsed-dose-rate and high-dose-rate afterloading machines; the use of new 3D/4D planning systems has additionally improved the quality of the treatment. The aim of the present study was to present short summaries of current studies on brachytherapy for the most frequently diagnosed tumors. Data presented in this manuscript should help especially young physicians or physicists to explore and introduce brachytherapy in cancer treatments.

  5. Brachytherapy for elderly patients with stage II tongue cancer

    International Nuclear Information System (INIS)

    Kimura, Tomoki; Hirokawa, Yutaka; Fujita, Minoru; Murakami, Yuji; Kenjo, Masahiro; Kaneyasu, Yuko; Ito, Katsuhide

    2003-01-01

    In treatment choices of stage II (T2N0M0) tongue cancer, brachytherapy is less invasive and superior in function preservation, therefore its role is more important in elderly patients. The aim of this study was to evaluate treatment results and morbidity of brachytherapy for elderly patients with stage II tongue cancer. Between 1980 and 2001, 198 patients with stage II tongue cancer were treated with brachytherapy at Hiroshima University Hospital. Patient ages ranged from 21 to 89 years old (median: 62 years old). Patients were divided into three groups as follows: 119 patients younger than 65 years old (Non-Elderly group), 53 patients between 65 and 75 years old (Junior Elderly group), and 26 patients 75 years or older (Senior Elderly group). Radiotherapy was performed in 101 patients with brachytherapy alone, and in 97 patients with brachytherapy and external radiotherapy. Chemotherapy was also performed in 77 patients. Follow-up period ranged from 4 to 243 months (median: 55 months). The 5-year local control rate was 85% in the Non-Elderly group, 85% in the Junior Elderly group and 81% in the Senior Elderly group. There was no significant difference among these groups. The 5-year cause-specific survival rate was 85%, 81% and 70% respectively. The Senior Elderly group showed poorer cause-specific survival rate than the other two groups (p=0.03). There was also a tendency of higher incidence of neck metastasis and low salvage rate by neck dissection in the Senior Elderly group. Although the Senior Elderly group showed poorer cause-specific survival rate, the local control rate was similar to those of the other two groups. Brachytherapy is an effective treatment option for elderly patients with stage II tongue cancer. (author)

  6. Volume correction factor in time dose relationships in brachytherapy

    International Nuclear Information System (INIS)

    Supe, S.J.; Sasane, J.B.

    1987-01-01

    Paterson's clinical data about the maximum tolerance doses for various volumes of interstitial implants with Ra-226 delivered in seven days was made use of in deriving volume correction factors for TDF and CRE concepts respectively for brachytherapy. The derived volume correction factors for TDF and for CRE differ fromthe one assumed for CRE by Kirk et al. and implied for TDF by Goitein. A normalising volume of 70 cc has been suggested for both CRE and TDF concepts for brachytherapy. A table showing the volume corrected TDF is presented for various volumes and dose rates for continuous irradiation. The use of this table is illustrated with examples. (orig.) [de

  7. Complications of esophageal stenting after radiotherapy and brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yorozu, Atsunori; Dokiya, Takushi; Ogita, Mikio; Kutuki, Shoji; Oki, Yosuke [National Second Hospital of Tokyo (Japan)

    1997-11-01

    The purpose of our study was to evaluate safety and complications of stenting after radiotherapy and brachytherapy. Fifteen of 21 patients showed improvement of dysphagia by stenting. But 6 of 21 patients had perforation or massive bleeding relating to stents. The risk for perforation or hemorrhage appears to be even higher in patients who have previously undergone radical radiotherapy and brachytherapy within one month before stenting. Stenting at 6 months or more after radical radiotherapy seems to be an effective and safe method of long-lasting palliation for severe dysphagia with recurrent esophageal cancer. (author)

  8. Australian high-dose-rate brachytherapy protocols for gynaecological malignancy

    International Nuclear Information System (INIS)

    MacLeod, C.; Dally, M.; Stevens, M.; Thornton, D.; Carruthers, S.; Jeal, P.

    2001-01-01

    There is no consensus over the optimal dose fractionation schedules for high-dose-rate (HDR) brachytherapy used for gynaecological malignancy. In Australian public hospital departments of radiation oncology, HDR brachytherapy for gynaecological cancer is being more commonly used. A survey of public departments that are using this technology, or that plan to introduce this technology, was performed. Their current protocols are presented. In general, protocols are similar biologically; however, the practical aspects such as the number of fractions given do vary and may reflect resource restrictions or, alternatively, differences in interpretations of the literature and of the best protocols by clinicians. Copyright (2001) Blackwell Science Pty Ltd

  9. Radiographic Control of 137-Cs Brachytherapy Sources

    International Nuclear Information System (INIS)

    Bistrovic, M.; Viculin, T.; Jurkovic, S.

    2003-01-01

    1 37C s brachytherapy sources are practical for the intracavitary application due to their relatively long lifetime (T 1/2 = 30 y). On the other hand, due to the relatively low energy (0.66 MeV) of the emitted photons, they are suitable for an efficient radiation protection. The dose distribution around the sources is usually calculated by a specific program. However this program requires the knowledge of the position of sources within the applicator as well as the distribution of activity along them. The only way to learn these data is to make an X-ray picture of applicators and sources superimposed to the autoradiography of every source. It is difficult to achieve satisfactory radiographs with high dose rate sources with standard X-ray film material because autoradiography covers the structure of the radiographic shadow. The problem can be overcome either by applying a high intensity X-ray or gamma beam (originating from a radiotherapeutic machine), or by using photographic material of very low sensitivity, for example photographic paper. Combining both possibilities one can obtain satisfactory images. (author)

  10. Endovascular brachytherapy to prevent restenosis after angioplasty

    International Nuclear Information System (INIS)

    Wohlgemuth, W.A.; Bohndorf, K.

    2003-01-01

    Endovascular radiotherapy is the first effective prophylaxis of restenosis after percutaneous transluminal angioplasty (PTA) and stenting. The FDA recently approved two devices for the delivery of intracoronary radiation following coronary artery stenting. Published multicenter, double-blind, randomized trials of intracoronary radiation therapy report good results for preventing in-stent restenosis, while the data for the peripheral circulation are still inconclusive. Beta-emitters are easier applicable and probably also safer, whereas gamma-emitters have been more extensively evaluated clinically so far. Primary indication for endovascular brachytherapy are patients at high risk for restenosis, such as previous restenoses, in-stent hyperplasia, long stented segment, long PTA lesion, narrow residual vascular lumen and diabetes. Data from coronary circulation suggest a safety margin of at least 4 to 10 mm at both ends of the angioplastic segment to avoid edge restenosis. To prevent late thrombosis of the treated coronary segment, antiplatelet therapy with clopidogrel and aspirin are recommended for at least 6 months after PTA and for 12 months after a newly implanted stent. An established medication regimen after radiotherapy of peripheral arteries is still lacking. (orig.) [de

  11. A quality management program in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Chakri, Abderrahim; Thomadsen, Bruce

    2002-01-01

    While simple, intravascular brachytherapy (IVB) presents a considerable potential for harm to the patient. The medical physicist maintains the responsibility to minimize the likelihood of operational problems or dosimetric errors. The principals for safe operation remain the same as with any radiotherapy treatment: to deliver the correct dose, to the correct location, safety. To develop an effective and comprehensive quality management (QM) program for IVB, a physicist should utilize proven risk assessment techniques rather than simply thinking of things to check, and follow guidances such as ISO9001:2000. The proposed QM program includes the following: Procedures designed to assure the safety of the patient: Identification of the patient; tests of the integrity and patency for the delivery catheter, operation of the source train, and patency of the catheter in the treatment position; a check for recovery preparations; and verification of source recovery. Procedures to assure positional accuracy of the treatment: Verification of the positioning the catheter in the artery and of the sources in the catheter. Procedures to assure dosimetry accuracy: Acceptance testing of the device, including verification of the source strength and uniformity, and of the treatment duration tables; verification of the treatment prescription and duration for each patient; and control measures that minimize the likelihood of errors removing the source at the correct time

  12. Radiation safety parameters following prostate brachytherapy

    International Nuclear Information System (INIS)

    Smathers, Sesalie; Wallner, Kent; Korssjoen, Tammy; Bergsagel, Carl; Hudson, Rick H.; Sutlief, Steven; Blasko, John

    1999-01-01

    Purpose: To determine the degree and variability of radiation exposure to the general public from patients after I-125 or Pd-103 prostate brachytherapy. Methods and Materials: Radiation exposure measurements were made from 38 consecutive, unselected patients with stage T1 or T2 prostatic carcinoma who had trans perineal I-125 or Pd-103 implants at the University of Washington in 1998. Results: The exposure rate at the anterior skin surface following a I-125 implant ranged from 2.2 to 8.9 mrem/hour (average: 5.0). The exposure rate at the anterior skin surface from a Pd-103 implant ranged from 0.5 to 4.9 mrem/hour (average: 1.7). Based on the current Nuclear Regulatory Commission (NRC) regulations the time required to reach the annual limit at the anterior skin surface would be 20 hours for I-125 and 59 hours for Pd-103. For exposure at the lateral skin surface, the times would exceed 500 hours for either isotope. Conclusions: This data suggest that patients need not be concerned about being a radiation risk to the general public following their procedure

  13. Radiation Protection Training in Intracoronary Brachytherapy

    International Nuclear Information System (INIS)

    Prieto, C.; Vano, E.; Fernandez, J. M.; Sabate, M.; Galvan, C.; Meiggs, L.; Corral, J. M.

    2003-01-01

    To report the educational objectives and contents on Radiation Protection (RP) for the practice of Intracoronary Brachytherapy (ICB) procedures. The wide international experience on training programs for ICB as well as our own experience organizing several courses aimed at Cardiologists, Radio therapists and Medical Physicists has been used to elaborate specific RP objectives and contents. The objectives, differentiated for Cardiologists, Radio therapists, Medical Physicists, Nurses and Technicians, pretend to guarantee the safety and RP of both patient and staff in the procedures of ICB. The objectives are necessarily different because their RP formation and their role in the procedure are different. The general topics included in RP training programmes for ICB could be: general topics on RP (Interaction of radiation and matter, RP principles, radiobiology, etc), principles of operation of ICB and interventional X-ray equipment, quantification of radiation dose and risks, optimisation of protection of staff and patients, accidents and emergencies, regulations, responsibilities, quality assurance program, handling of ICB sources, installation and commissioning. Training programs based on the objectives presented in this paper would encourage positive safety culture in ICB and can also be used as a starting point by the Regulatory Authority for the authorization of new Installations and credentialing of professionals involved in this technique as well as for the continuous education of the staff involved. (Author) 10 refs

  14. Dose assessment for brachytherapy with Henschke applicator

    International Nuclear Information System (INIS)

    Yu, Pei-Chieh; Chao, Tsi-Chian; Tung, Chuan-Jong; Wu, Ching-Jung; Lee, Chung-Chi

    2011-01-01

    Dose perturbation caused by the Henschke applicator is a major concern for the brachytherapy planning system (BPS) in recent years. To investigate dose impact owing to neglect of the metal shielding effect, Monte Carlo (MC) simulation, BPS calculation, and film measurement have been performed for dose assessment in a water phantom. Additionally, a cylindrical air cavity representing the rectum was added into the MC simulation to study its effect on dose distribution. Monte Carlo N-Particle Transport Code (MCNP) was used in this study to simulate the dose distribution using a mesh tally. This Monte Carlo simulation has been validated using the TG-43 data in a previous report. For the measurement, the Henschke applicator was placed in a specially-designed phantom, and Gafchromic films were inserted in the center plane for 2D dose assessment. Isodose distributions with and without the Henschke applicator by the MC simulation show significant deviation from those by the BPS. For MC simulation, the isodose curves shrank more significantly when the metal applicator was applied. For the impact of the added air cavity, the results indicate that it is hard to distinguish between with and without the cavity. Thus, the rectum cavity has little impact on the dose distribution around the Henschke applicator.

  15. Dose optimisation in single plane interstitial brachytherapy

    DEFF Research Database (Denmark)

    Tanderup, Kari; Hellebust, Taran Paulsen; Honoré, Henriette Benedicte

    2006-01-01

    patients,       treated for recurrent rectal and cervical cancer, flexible catheters were       sutured intra-operatively to the tumour bed in areas with compromised       surgical margin. Both non-optimised, geometrically and graphically       optimised CT -based dose plans were made. The overdose index...... on the       regularity of the implant, such that the benefit of optimisation was       larger for irregular implants. OI and HI correlated strongly with target       volume limiting the usability of these parameters for comparison of dose       plans between patients. CONCLUSIONS: Dwell time optimisation significantly......BACKGROUND AND PURPOSE: Brachytherapy dose distributions can be optimised       by modulation of source dwell times. In this study dose optimisation in       single planar interstitial implants was evaluated in order to quantify the       potential benefit in patients. MATERIAL AND METHODS: In 14...

  16. Halo's production in vitro on brachytherapy experiments

    International Nuclear Information System (INIS)

    Cuperschmid, Ethel M.; Sarmento, Eduardo V.; Campos, Tarcisio P.R.

    2011-01-01

    Since earlier of 1960, one of the most significant contributions of radiation biology has been the theory of cell killing as a function of increasing doses of a cytotoxic agent, as well as the demonstration of repair of sublethal or potentially lethal damage after irradiation. The impact of cellular and molecular radiobiology, by exploitation of cellular mechanisms related to apoptosis, may be the cell killing with irradiation by including changes other than unrepaired DNA damage. Based on the understanding of the tumor microenvironment and how growth factors and proteins produced by irradiated cells may alter cellular processes, improved combined-modality strategies may emerge. This effect was show since 1960's, but here we propose to demonstrate this phenomenon in Brachytherapy. The present goal is to verify the macroscopic response through the production and analysis of clonogenic control based on halos generation by radioactive seeds of Ho-165 and Sm-153, aiming to study the effect of this type of irradiation. Confluent cell culture flasks with HeLa cell line were subjected to radiation in a period up to five half-lives of radionuclide, respectively. Devices were introduced which set the polymer-ceramic Ho-165 and Sm-153 seeds in the vials. After a period of exposure, the flasks were stained with violet Gensiana. The results showed the formation of halos control of confluent cancer cells. This paper will describe these experiments in the current stage of the research and report the implications of this new way of therapy for cancer treatment. (author)

  17. Embryo yield in llamas synchronized with two different intravaginal progesterone-releasing devices and superovulated with eCG

    Directory of Open Access Journals (Sweden)

    Juan F. Aller

    2015-09-01

    Full Text Available The objectives of this study were to compare the effects of two intravaginal devices (ID containing the same dose (0.5 g of progesterone (P4 on subsequent ovarian response, embryo production and circulating P4 concentration profile in llamas (Lama glama treated with equine chorionic gonadotropin (eCG for ovarian superstimulation. Female llamas were randomly assigned (n = 10 llamas per group to one of the following groups and treated (Day 0 with an ID containing 0.5 g of vegetal P4 to synchronize the emergence of a new follicular wave: i DIB 0.5® and ii Cronipres M15®. On Day 3 llamas were intramuscularly treated with 1000 IU of eCG. The IDs were removed on Day 7. Llamas were naturally mated (Day 9 and treated with GnRH analogue to induce ovulation. A second mating was allowed 24 h later. Embryos were collected between 7 and 8 days after the first mating. Blood samples were taken every day from Day 0 to Day 7 to measure circulating P4 concentrations. The results indicated that DIB device maintained greater plasma P4 levels as compared to Cronipres until Day 2. However, the mean (± SD number of corpora lutea and recovered embryos was not affected (p < 0.05 by the type of ID (5.3 ± 2.6 vs 4.2 ± 2.2 and 3.5 ± 2.7 vs 2.6 ± 3.0 for DIB and Cronipres, respectively. In conclusion, both DIB and Cronipres devices can be successfully used to synchronize the emergence of follicular wave prior to a single dose of eCG in superovulation protocol in llamas.

  18. Embryo yield in llamas synchronized with two different intravaginal progesterone-releasing devices and superovulated with eCG

    Energy Technology Data Exchange (ETDEWEB)

    Aller, J.F.; Abalos, M.C.; Acuña, F.A.; Virgili, R.; Requena, F.; Cancino, A.K.

    2015-07-01

    The objectives of this study were to compare the effects of two intravaginal devices (ID) containing the same dose (0.5 g) of progesterone (P4) on subsequent ovarian response, embryo production and circulating P4 concentration profile in llamas (Lama glama) treated with equine chorionic gonadotropin (eCG) for ovarian superstimulation. Female llamas were randomly assigned (n = 10 llamas per group) to one of the following groups and treated (Day 0) with an ID containing 0.5 g of vegetal P4 to synchronize the emergence of a new follicular wave: i) DIB 0.5® and ii) Cronipres M15®. On Day 3 llamas were intramuscularly treated with 1000 IU of eCG. The IDs were removed on Day 7. Llamas were naturally mated (Day 9) and treated with GnRH analogue to induce ovulation. A second mating was allowed 24 h later. Embryos were collected between 7 and 8 days after the first mating. Blood samples were taken every day from Day 0 to Day 7 to measure circulating P4 concentrations. The results indicated that DIB device maintained greater plasma P4 levels as compared to Cronipres until Day 2. However, the mean (± SD) number of corpora lutea and recovered embryos was not affected (p < 0.05) by the type of ID (5.3 ± 2.6 vs 4.2 ± 2.2 and 3.5 ± 2.7 vs 2.6 ± 3.0 for DIB and Cronipres, respectively). In conclusion, both DIB and Cronipres devices can be successfully used to synchronize the emergence of follicular wave prior to a single dose of eCG in superovulation protocol in llamas. (Author)

  19. Premature ejaculation results from partners' mismatch: development and validation of index of intra-vaginal ejaculation latency time.

    Science.gov (United States)

    Cai, L; Wen, Y; Jiang, M; Zeng, M; Zhang, B

    2016-05-01

    Mismatch of partners in premature ejaculation (PE) regarding intra-vaginal ejaculation latency time (IELT) is usually neglected. Here we proposed the concept and evaluated the use of index of IELT (IIELT) as an objective diagnostic tool for PE. Data from 103 self-reporting PE patients and 59 normal controls were collected. The expected IELTs of both the male and female partners were provided by each participating couple in two questionnaires. IIELT=stopwatch IELT/(1/2 the male's expected IELT+1/2 the female's expected IELT). The stopwatch IELTs were 1.74±1.4 min (PE group) and 14.45±11.0 min (control group), PIELTs were 15.65±8.7 min (men) and 14.16±6.9 min (women) in the PE group, and 21.3±16.1 min (men) and 20.04±13.47 min (women) in the control group, P<0.05. The calculated IIELTs were 0.14±0.12 (PE group) and 0.83±0.60 (control group), P<0.05. The best cut-off point was 0.658, the Youden index was 0.652, sensitivity was 0.991, specificity was 0.661, positive predictive probability was 83.46% and negative predictive probability was 97.6%. We concluded that IIELT was an integrated measurement of the couples' sexual equilibrium and demonstrated that it provided a simple and objective screening indicator for diagnosing self-reported PE.

  20. The diagnostic value of the premature ejaculation diagnostic tool and its association with intravaginal ejaculatory latency time.

    Science.gov (United States)

    Kam, Sung Chul; Han, Deok Hyun; Lee, Sung Won

    2011-03-01

    Premature ejaculation (PE) is the most prevalent male ejaculation disorder. The premature ejaculation diagnostic tool (PEDT) was developed to systematically apply the DSM-IV-TR criteria in diagnostic PE. To evaluate the diagnostic value of the PEDT and its association with intravaginal ejaculatory latency time (IELT). (i) Korean validation of PEDT: data was collected from men interviewed by one of the two clinical experts, who made a diagnostic of present or absence of PE, using DSM-IV-TR criteria. A total of 103 patients with PE and 100 men without PE were enrolled into the study and requested to complete the PEDT; and (ii) The correlation between IELT and PEDT: 200 participants were enrolled and each participant was asked to make out PEDT. All participants were requested to measure IELT. Validity and reliability of the PEDT and its association with IELT. The geometric mean IELT of the PE group was 115.37 ± 78.14 seconds. The number of men reporting IELTs of 2 minutes were 28 (28.6%), 29 (29.6%), and 41 (41.8%), respectively. The Cronbach's alpha score was calculated as 0.93, showing adequate internal consistency. The test-retest correlation coefficients of each item were higher than 0.72 and the correlation coefficients of the total score was 0.88. (P IELT showed an adequate negative correlation. (ρ = -0.77, P IELT ≤ 2 minutes) and IELT showed a negative correlation. (ρ = -0.6, P < 0.0001) The PEDT was highly effective in detecting the presence of PE. The result of our study supports its validity as a diagnostic tool in the clinical setting. © 2010 International Society for Sexual Medicine.

  1. Intravaginal cytomegalovirus (CMV challenge elicits maternal viremia and results in congenital transmission in a guinea pig model

    Directory of Open Access Journals (Sweden)

    Schleiss Mark R

    2011-03-01

    Full Text Available Abstract Background The objective of this study was to compare intravaginal (ivg and subcutaneous (sc administration of the guinea pig cytomegalovirus (GPCMV in pregnant and non-pregnant guinea pigs. These studies tested the hypotheses that ivg infection would elicit immune responses, produce maternal viremia, and lead to vertical transmission, with an efficiency similar to the traditionally employed sc route. Results Four groups of age- and size-matched guinea pigs were studied. Two groups were pregnant, and two groups were not pregnant. Animals received 5x105 plaque-forming units (PFU of a GPCMV reconstituted from an infectious bacterial artificial chromosome (BAC construct containing the full-length GPCMV genome. Seroconversion was compared by IgG ELISA, and viremia (DNAemia was monitored by PCR. In both pregnant and non-pregnant animals, sc inoculation resulted in significantly higher serum ELISA titers than ivg inoculation at 8 and 12 weeks post-infection. Patterns of viremia (DNAemia were similar in animals inoculated by either sc or ivg route. However, in pregnant guinea pigs, animals inoculated by both routes experienced an earlier onset of DNAemia than did non-pregnant animals. Neither the percentage of dead pups nor the percentage of GPCMV positive placentas differed by inoculation route. Conclusions In the guinea pig model of congenital CMV infection, the ivg route is as efficient at causing congenital infection as the conventional but non-physiologic sc route. This finding could facilitate future experimental evaluation of vaccines and antiviral interventions in this highly relevant animal model.

  2. A long-acting integrase inhibitor protects female macaques from repeated high-dose intravaginal SHIV challenge.

    Science.gov (United States)

    Andrews, Chasity D; Yueh, Yun Lan; Spreen, William R; St Bernard, Leslie; Boente-Carrera, Mar; Rodriguez, Kristina; Gettie, Agegnehu; Russell-Lodrigue, Kasi; Blanchard, James; Ford, Susan; Mohri, Hiroshi; Cheng-Mayer, Cecilia; Hong, Zhi; Ho, David D; Markowitz, Martin

    2015-01-14

    Long-acting GSK1265744 (GSK744 LA) is a strand transfer inhibitor of the HIV/SIV (simian immunodeficiency virus) integrase and was shown to be an effective preexposure prophylaxis (PrEP) agent in a low-dose intrarectal SHIV (simian-human immunodeficiency virus) rhesus macaque challenge model. We examined the pharmacokinetics and efficacy of GSK744 LA as PrEP against repeat high-dose intravaginal SHIV challenge in female rhesus macaques treated with Depo-Provera (depot medroxyprogesterone acetate), which promotes viral transmission vaginally. When Depo-Provera-treated female rhesus macaques were dosed with GSK744 LA (50 mg/kg) monthly, systemic and tissue drug concentrations were lower than previously observed in male rhesus macaques. GSK744 concentrations were fivefold lower on average in cervical tissues than in rectal tissues. Eight female rhesus macaques were treated with GSK744 LA at week 0, and four female rhesus macaques served as controls. All animals received a high-dose challenge of SHIV162P3 at week 1. No infection was detected in GSK744 LA-treated rhesus macaques, whereas viremia was detected 1 to 2 weeks after SHIV challenge in all control animals. The GSK744 LA-treated rhesus macaques were given a second administration of drug at week 4 and further challenged at weeks 5 and 7. GSK744 LA treatment protected six of eight female rhesus macaques against three high-dose SHIV challenges, whereas all control animals became infected after the first challenge (P = 0.0003, log-rank test). These results support further clinical development of GSK744 LA for PrEP. Copyright © 2015, American Association for the Advancement of Science.

  3. Intravaginal administration of metformin hydrochloride loaded cationic niosomes amalgamated with thermosensitive gel for the treatment of polycystic ovary syndrome: In vitro and in vivo studies.

    Science.gov (United States)

    Saini, Neetu; Sodhi, Rupinder Kaur; Bajaj, Lotika; Pandey, Ravi Shankar; Jain, Upendra Kumar; Katare, Om Prakash; Madan, Jitender

    2016-08-01

    Metformin hydrochloride (MTF-HCl) is extensively recommended by physicians for the treatment of polycystic ovary syndrome (PCOS). Mechanistically, MTF-HCl activates AMP-dependent kinase-α (AMPK-α) pathway to decrease the glucose production, enhances fatty acid oxidation and elevates the uptake of glucose in tissues. However, despite favourable physicochemical properties, oral administration of MTF-HCl is associated with impaired bioavailability (50-60%), lactic-acidosis and frequent dosing (500mg 2-3 times a day) in PCOS that ultimately influence the patient compliance. Therefore, in present investigation, MTF-HCl loaded unmodified and cationic small unilamellar niosomes were separately amalgamated with thermosensitive gel (MTF-HCl-SUNs-Gel and MTF-HCl-C-SUNs-Gel) for the treatment of PCOS through vaginal route of administration. MTF-HCl-SUNs and MTF-HCl-C-SUNs were separately prepared by reverse phase evaporation method. The nanovesicle size and zeta-potential of MTF-HCl-C-SUNs were measured to be 210.3±14.8-nm (Ptreatment of PCOS rats under scheduled dose-dosage regimen with oral MTF-HCl solution, intravaginal MTF-HCl-SUNs-Gel and intravaginal MTF-HCl-C-SUNs-gel exhibited remarkable alterations, recruitment and development of normal follicles in addition to normalization of level of various hormones in PCOS. In conclusion, MTF-C-SUNs-Gel has paved the way for developing intravaginal dosage form of MTF-HCl for the treatment of PCOS. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Efficacy of intravaginal dehydroepiandrosterone (DHEA) on moderate to severe dyspareunia and vaginal dryness, symptoms of vulvovaginal atrophy, and of the genitourinary syndrome of menopause.

    Science.gov (United States)

    Labrie, Fernand; Archer, David F; Koltun, William; Vachon, Andrée; Young, Douglas; Frenette, Louise; Portman, David; Montesino, Marlene; Côté, Isabelle; Parent, Julie; Lavoie, Lyne; Beauregard, Adam; Martel, Céline; Vaillancourt, Mario; Balser, John; Moyneur, Érick

    2016-03-01

    The aim of this study is to confirm the local beneficial effects of intravaginal dehydroepiandrosterone (DHEA, Prasterone) on moderate to severe dyspareunia or pain at sexual activity, the most frequent symptom of vulvovaginal atrophy due to menopause or genitourinary syndrome of menopause (GSM). In a prospective, randomized, double-blind, and placebo-controlled phase III clinical trial, the effect of daily intravaginal 0.50% DHEA (6.5 mg) (Prasterone, EndoCeutics) was examined on four coprimary objectives, namely percentage of parabasal cells, percentage or superficial cells, vaginal pH, and moderate to severe pain at sexual activity (dyspareunia) identified by the women as their most bothersome vulvovaginal atrophy symptom. The intent-to-treat population included 157 and 325 women in the placebo and DHEA-treated groups, respectively. After daily intravaginal administration of 0.50% DHEA for 12 weeks, when compared to baseline by the analysis of covariance test, the percentage of parabasal cells decreased by 27.7% over placebo (P < 0.0001), whereas the percentage of superficial cells increased by 8.44% over placebo (P < 0.0001), vaginal pH decreased by 0.66 pH unit over placebo (P < 0.0001), and pain at sexual activity decreased by 1.42 severity score unit from baseline or 0.36 unit over placebo (P = 0.0002). On the other hand, moderate to severe vaginal dryness present in 84.0% of women improved at 12 weeks by 1.44 severity score unit compared to baseline, or 0.27 unit over placebo (P = 0.004). At gynecological evaluation, vaginal secretions, epithelial integrity, epithelial surface thickness, and color all improved by 86% to 121% over the placebo effect (P < 0.0001 for all comparisons with placebo). Serum steroid levels remained well within the normal postmenopausal values according to the involved mechanisms of intracrinology. The only side effect reasonably related to treatment is vaginal discharge due to melting of the vehicle at

  5. Resultados preliminares de cultivo intravaginal de ovocitos-inyección intracitoplasmática de espermatozoides (INVO-ICSI), en el centro de fertilidad procrear

    OpenAIRE

    Hilario, Roly; Dueñas, Julio; Gonzales, Max; García, Javier; Romero, Rocío

    2014-01-01

    Objetivos: Conocer los resultados preliminares de tasa de embarazo por transferencia en las pacientes en quienes se realizó cultivo intravaginal de ovocitos-inyección intracitoplasmática de espermatozoides (INVO-ICSI) en un centro de fertilidad. Diseño: Estudio descriptivo de una serie de casos. Institución: Centro de Fertilidad Procrear, Lima, Perú. Participantes: Parejas con tratamiento de infertilidad. Intervenciones: Se analizó todos los 13 procedimientos de INVO-ICSI realizados en 12 pac...

  6. High Levels of Inflammatory Cytokines in the Reproductive Tract of Women with BV and Engaging in Intravaginal Douching: A Cross-Sectional Study of Participants in the Women Interagency HIV Study.

    Science.gov (United States)

    Alcaide, Maria L; Rodriguez, Violeta J; Brown, Megan R; Pallikkuth, Suresh; Arheart, Kristopher; Martinez, Octavio; Roach, Margaret; Fichorova, Raina N; Jones, Deborah L; Pahwa, Savita; Fischl, Margaret A

    2017-04-01

    High levels of inflammatory cytokines in the genital tract suggest mucosal vulnerability and increased risk of HIV and sexually transmitted infection (STI) acquisition. Intravaginal douching is associated with bacterial vaginosis (BV) in women in the United States, and both douching and BV are linked to HIV and STI acquisition. This study evaluates inflammatory cytokines in the genital tract to increase understanding of the effects of both BV and intravaginal douching to the vaginal mucosa. A cross-sectional study of participants in the Miami WIHS investigated 72 reproductive age women (45 HIV + and 27 high-risk HIV - ) who completed intravaginal douching questionnaires and underwent collection of vaginal swabs and cervicovaginal lavages (CVLs). BV was assessed using the Nugent score. Inflammatory cytokines in the CVLs (interleukin [IL]-6, IL-8, IL-1α, IL-1β, soluble intracellular adhesion molecule-1 [sICAM-1], interferon [IFN]α2, chemokine C ligand 5 (CCL5), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP1), tumor necrosis factor alpha (TNFα), and secretory leukocyte protease inhibitor [SLPI]) were measured. Fourteen (19%) women reported intravaginal douching; 24 (33%) had BV. BV, intravaginal douching, and HIV were associated with higher levels of inflammatory cytokines. After controlling for demographic and risk factors and HIV status, women who had BV and douched had higher levels of inflammatory cytokines than those without BV and who did not douche, or who only had BV or only douched. These findings suggest that BV and douching are associated with greater mucosal inflammation and may facilitate HIV acquisition and transmission. Although longitudinal studies are needed to determine temporal associations and causality, interventions to decrease rates of intravaginal douching and BV could significantly decrease women's risks of acquiring STIs and HIV and limit the spread of HIV.

  7. Underuse of brachytherapy for the treatment of dysphagia owing to esophageal cancer. An Italian survey.

    Science.gov (United States)

    Fuccio, Lorenzo; Guido, Alessandra; Hassan, Cesare; Frazzoni, Leonardo; Arcelli, Alessandra; Farioli, Andrea; Giaccherini, Lucia; Galuppi, Andrea; Mandolesi, Daniele; Cellini, Francesco; Mantello, Giovanna; Macchia, Gabriella; de Bortoli, Nicola; Repici, Alessandro; Valentini, Vincenzo; Bazzoli, Franco; Morganti, Alessio Giuseppe

    2016-10-01

    International guidelines strongly recommend brachytherapy as valid alternative or in addition to stenting in patients with dysphagia owing to esophageal cancer. However, for not well understood reasons, brachytherapy is definitively underused for the palliative treatment of malignant dysphagia. Aim of the current survey was to investigate the use of brachytherapy for the treatment of malignant dysphagia in Italy. A structured questionnaire was submitted to the 1510 members of the Italian Association of Radiation Oncologists (AIRO). These members refer to 177 centres of radiotherapy across Italy and in 68 (38.4%) of them brachytherapy is routinely performed. Of the 1510 invited members, 178 completed the survey (11.7%). The answers provided by the 178 participants allowed to get information on 40 out of 68 brachytherapy centres (58.8%). Seven out of 40 (17.5%) centres perform brachytherapy of the oesophagus, in 3 out of 40 (7.5%) centres brachytherapy represents the first line of treatment. The main reason why brachytherapy is not routinely performed is the lack of experience. Despite the strong recommendations of the international guidelines and the wide diffusion of brachytherapy centres across Italy, only very few of them routinely considered brachytherapy for the treatment of dysphagia due to esophageal cancer. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  8. Current status of brachytherapy in Korea: a national survey of radiation oncologists.

    Science.gov (United States)

    Kim, Haeyoung; Kim, Joo Young; Kim, Juree; Park, Won; Kim, Young Seok; Kim, Hak Jae; Kim, Yong Bae

    2016-07-01

    The aim of the present study was to acquire information on brachytherapy resources in Korea through a national survey of radiation oncologists. Between October 2014 and January 2015, a questionnaire on the current status of brachytherapy was distributed to all 86 radiation oncology departments in Korea. The questionnaire was divided into sections querying general information on human resources, brachytherapy equipment, and suggestions for future directions of brachytherapy policy in Korea. The response rate of the survey was 88.3%. The average number of radiation oncologists per center was 2.3. At the time of survey, 28 centers (36.8%) provided brachytherapy to patients. Among the 28 brachytherapy centers, 15 (53.5%) were located in in the capital Seoul and its surrounding metropolitan areas. All brachytherapy centers had a high-dose rate system using (192)Ir (26 centers) or (60)Co (two centers). Among the 26 centers using (192)Ir sources, 11 treated fewer than 40 patients per year. In the two centers using (60)Co sources, the number of patients per year was 16 and 120, respectively. The most frequently cited difficulties in performing brachytherapy were cost related. A total of 21 centers had a plan to sustain the current brachytherapy system, and four centers noted plans to upgrade their brachytherapy system. Two centers stated that they were considering discontinuation of brachytherapy due to cost burdens of radioisotope source replacement. The present study illustrated the current status of brachytherapy in Korea. Financial difficulties were the major barriers to the practice of brachytherapy.

  9. The difference of scoring dose to water or tissues in Monte Carlo dose calculations for low energy brachytherapy photon sources.

    Science.gov (United States)

    Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-03-01

    The goal of this work is to compare D(m,m) (radiation transported in medium; dose scored in medium) and D(w,m) (radiation transported in medium; dose scored in water) obtained from Monte Carlo (MC) simulations for a subset of human tissues of interest in low energy photon brachytherapy. Using low dose rate seeds and an electronic brachytherapy source (EBS), the authors quantify the large cavity theory conversion factors required. The authors also assess whether ap plying large cavity theory utilizing the sources' initial photon spectra and average photon energy induces errors related to spatial spectral variations. First, ideal spherical geometries were investigated, followed by clinical brachytherapy LDR seed implants for breast and prostate cancer patients. Two types of dose calculations are performed with the GEANT4 MC code. (1) For several human tissues, dose profiles are obtained in spherical geometries centered on four types of low energy brachytherapy sources: 125I, 103Pd, and 131Cs seeds, as well as an EBS operating at 50 kV. Ratios of D(w,m) over D(m,m) are evaluated in the 0-6 cm range. In addition to mean tissue composition, compositions corresponding to one standard deviation from the mean are also studied. (2) Four clinical breast (using 103Pd) and prostate (using 125I) brachytherapy seed implants are considered. MC dose calculations are performed based on postimplant CT scans using prostate and breast tissue compositions. PTV D90 values are compared for D(w,m) and D(m,m). (1) Differences (D(w,m)/D(m,m)-1) of -3% to 70% are observed for the investigated tissues. For a given tissue, D(w,m)/D(m,m) is similar for all sources within 4% and does not vary more than 2% with distance due to very moderate spectral shifts. Variations of tissue composition about the assumed mean composition influence the conversion factors up to 38%. (2) The ratio of D90(w,m) over D90(m,m) for clinical implants matches D(w,m)/D(m,m) at 1 cm from the single point sources, Given

  10. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    DEFF Research Database (Denmark)

    Bert, Christoph; Kellermeier, Markus; Tanderup, Kari

    2016-01-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes...

  11. Pulsed dose rate brachytherapy – is it the right way?

    Directory of Open Access Journals (Sweden)

    Janusz Skowronek

    2010-10-01

    Full Text Available Pulsed dose rate (PDR-BT treatment is a brachytherapy modality that combines physical advantages of high-doserate (HDR-BT technology (isodose optimization, radiation safety with the radiobiological advantages of low-dose-rate (LDR-BT brachytherapy. Pulsed brachytherapy consists of using stronger radiation source than for LDR-BT and producing series of short exposures of 10 to 30 minutes in every hour to approximately the same total dose in the sameoverall time as with the LDR-BT. Modern afterloading equipment offers certain advantages over interstitial or intracavitaryinsertion of separate needles, tubes, seeds or wires. Isodose volumes in tissues can be created flexibly by a combinationof careful placement of the catheter and the adjustment of the dwell times of the computerized stepping source.Automatic removal of the radiation sources into a shielded safe eliminates radiation exposures to staff and visitors.Radiation exposure is also eliminated to the staff who formerly loaded and unloaded multiplicity of radioactive sources into the catheters, ovoids, tubes etc. This review based on summarized clinical investigations, analyses the feasibility and the background to introduce this brachytherapy technique and chosen clinical applications of PDR-BT.

  12. Brachytherapy in Europe: philosophies, current practice and future directions

    International Nuclear Information System (INIS)

    Haworth, A.

    2000-01-01

    Full text: Five months sabbatical leave provided an opportunity to visit six radiotherapy centres in France, Holland and England. While brachytherapy philosophies and practices within each country were similar, there were considerable differences in attitudes between countries. The Institute Gustave Roussy, home of the Paris System and host for the French sector confirmed that the Paris System is still very much the preferred dosimetry method in this part of the world. Though their preference for low dose rate brachytherapy is still evident, high dose rate brachytherapy has found some applications but the rules of the Paris System are never far away and the words 'what about the hyperdose sleeve' are firmly implanted into this visitor's brain. The use of real time dosimetry for I-125 prostate brachytherapy at the Institute Curie (Paris) provided an interesting contrast to the standard pre and post implant dosimetry techniques commonly employed elsewhere. The two Dutch centres on the itinerary, in stark contrast to the traditional techniques seen in France, have applied the power of computers to investigate optimisation of the classic dosimetry systems and called on the analysis techniques (DVH, NTCP, TCP etc) now familiar to us all in external beam therapy. The Cookridge Hospital in England fitted somewhere between the French and Dutch centres. This centre showed how both modern and traditional techniques could be applied in an efficient way for a large variety of treatment sites. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  13. In vivo dosimetry: trends and prospects for brachytherapy

    DEFF Research Database (Denmark)

    Kertzscher, Gustavo; Rosenfeld, A.; Beddar, S.

    2014-01-01

    The error types during brachytherapy (BT) treatments and their occurrence rates are not well known. The limited knowledge is partly attributed to the lack of independent verification systems of the treatment progression in the clinical workflow routine. Within the field of in vivo dosimetry (IVD)...

  14. Source of hope [El Salvador’s only brachytherapy centre

    International Nuclear Information System (INIS)

    Falcon Castro, Nancy

    2010-01-01

    Set up in 2008 with the IAEA’s support, the Cancer Institute 'Dr. Narciso Diaz Bazan' is El Salvador’s only brachytherapy treatment facility for women affected by uterine cancer. To date, over 1000 women affected by cervical cancer have received treatment in the centre

  15. Urethral toxicity after LDR brachytherapy: experience in Japan.

    Science.gov (United States)

    Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

    2015-01-01

    Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. Endobronchial brachytherapy: the Saint-Louis Hospital experience

    International Nuclear Information System (INIS)

    Hennequin, C.; Durdux, C.; Housset, M.; Maylin, C.; Tredaniel, J.; Zalcman, G.; Hirsch, A.; Dray, M.; Manoux, D.; Perret, M.

    1997-01-01

    During the evolution of lung cancer, bronchial obstruction is often noticed and is sometimes responsible for serious symptoms. Several methods of des-obstruction can be proposed, including brachytherapy. Materials and methods: One hundred forty-nine patients, presenting with endobronchial brachytherapy were included into the study. Seventy-three were treated with curative intent, 47 with palliative intent and 29 with a combination of external irradiation and brachytherapy. We usually delivered a series of two 7-Gy fractions (1 cm from the catheter), the treatment being repeated one, two or three times. Results: When all symptoms were taken into account, respiratory function improvement was present in 79% of the patients. Among the 132 tumors that could be evaluated via a new endoscopy 2 months after treatment, 64 (48.5%) were in complete histological remission. The median survival was 14.4 months for the patients treated with curative intent. Eleven massive hemoptyses and 13 radiation bronchitides were observed. Conclusion: These results confirm the feasibility and good results related to endobronchial brachytherapy, though controlled studies are needed to better define its place in the therapeutic strategy of bronchial carcinomas. (authors)

  17. Brachytherapy in cervix cancers: techniques and concepts evolution

    International Nuclear Information System (INIS)

    Haie-Meder, C.; Crevoisier, R. de; Petrow, P.; Fromm, S.; Delapierre, M.; Albano, M.; Petit, C.; Briot, E.

    2003-01-01

    Brachytherapy plays an important role in the treatment of patients with cervical carcinoma. Technical modalities have evolved during the last years and have benefited from imaging modalities development, specially MRI. Imaging modalities contribute to a better knowledge of tumoral extension and critical organs. Ultrasound during brachytherapy has led to the almost complete eradication of uterine perforation. In the future, a more systematic use of systems allowing optimization may induce a better dose distribution in the tumor as well as in the critical organs. Recent data provided information in favor of a better analysis in the relative role of dose-rate, total dose and treated volume and their influence on the local control and complication incidence. Concomitant radio-chemotherapy represents a standard in the treatment of patients with tumoral size exceeding 4 cm. Some questions still remain: is concomitant chemotherapy of benefit during brachytherapy? Is there any place for complementary surgery, specially in patients with complete response after external irradiation with concomitant chemotherapy and brachytherapy? In order to answer the former question, a phase III randomized trial is going to start, with the Federation Nationale des Centres de Lutte Contre le Cancer as a promoter. (authors)

  18. Radiation exposure of nursing personnel to brachytherapy patients

    International Nuclear Information System (INIS)

    Cobb, P.D.; Kase, K.R.; Bjaerngard, B.E.

    1978-01-01

    The radiation exposure of nursing personnel to brachytherapy patients has been analyzed from data collected during the years 1973-1976, at four different hospitals. The average annual dose per exposed nurse ranged between 25 and 150 mrem. The radiation exposure per nurse was found to be proportional to the total potential exposure and was uncorrelated with the size of the nursing staff. (author)

  19. Dose determination in breast tumor in brachytherapy using Iridium-192

    International Nuclear Information System (INIS)

    Okuno, S.F.

    1984-01-01

    Thermoluminescent dosimetry studies in vivo and in vitro aiming to determing radiation dose in the breast tumor, in brachytherapy using Iridium-192 was done. The correlation between radiation doses in tumor and external surface of the breast was investigated for correcting the time interval of radiation source implantation. (author) [pt

  20. Radiation exposure after permanent prostate brachytherapy

    International Nuclear Information System (INIS)

    Cattani, Federica; Vavassori, Andrea; Polo, Alfredo; Rondi, Elena; Cambria, Raffaella; Orecchia, Roberto; Tosi, Giampiero

    2006-01-01

    Background and purpose: Limited information is available on the true radiation exposure and associated risks for the relatives of the patients submitted to prostate brachytherapy with permanent implant of radioactive sources and for any other people coming into contact with them. In order to provide appropriate information, we analyzed the radiation exposure data from 216 prostate cancer patients who underwent 125 I or 103 Pd implants at the European Institute of Oncology of Milan, Italy. Patients and methods: Between October 1999 and October 2004, 216 patients with low risk prostate carcinoma were treated with 125 I (200 patients) or 103 Pd (16 patients) permanent seed implantation. One day after the procedure, radiation exposure measurements around the patients were performed using an ionization chamber survey meter (Victoreen RPO-50) calibrated in dose rate at an accredited calibration center (calibration Centre SIT 104). Results: The mean dose rate at the posterior skin surface (gluteal region) following 125 I implants was 41.3 μSv/h (range: 6.2-99.4 μSv/h) and following 103 Pd implants was 18.9 μSv/h (range 5.0-37.3 μSv/h). The dose rate at 50 cm from the skin decreased to the mean value of 6.4 μSv/h for the 125 I implants and to the mean value of 1.7 μSv/h for the 103 Pd implants. Total times required to reach the annual dose limit (1 mSv/year) recommended for the general population by the European Directive 96/29/Euratom and by the Italian law (Decreto Legislativo 241/2000) at a distance of 50 cm from the posterior skin surface of the implanted patient would be 7.7 and 21.6 days for 125 I and for 103 Pd. Good correlation between the measured dose rates and both the total implanted activity and the distance between the most posteriorly implanted seed and the skin surface of the patients was found. Conclusions: Our data show that the dose rates at 50 cm away from the prostate brachytherapy patients are very low and that the doses possibly absorbed by the

  1. Isotope selection for patients undergoing prostate brachytherapy

    International Nuclear Information System (INIS)

    Cha, Christine M.; Potters, Louis; Ashley, Richard; Freeman, Katherine; Wang Xiaohong; Waldbaum, Robert; Leibel, Steven

    1999-01-01

    Purpose: Ultrasound-guided trans perineal interstitial permanent prostate brachytherapy (TIPPB) is generally performed with either 103 Pd or 125 I. The use of 125 I for low Gleason score tumors and 103 Pd for higher Gleason scores has been suggested based on isotope dose rate and cell doubling time observed in in vitro studies. While many centers follow these isotope selection criteria, other centers have elected to use only a single isotope, regardless of Gleason score. No clinical data have been published comparing these isotopes. This study was undertaken to compare outcomes between 125 I and 103 Pd in a matched pair analysis for patients undergoing prostate brachytherapy. Methods and Materials: Six hundred forty-eight consecutively treated patients with clinically confined prostate cancer underwent TIPPB between June 1992 and February 1997. Five hundred thirty-two patients underwent TIPPB alone, whereas 116 received pelvic external beam irradiation and TIPPB. Ninety-three patients received androgen deprivation therapy prior to TIPPB. The prescribed doses for TIPPB were 160 Gy for 125 I (pre-TG43) and 120 Gy for 103 Pd. Patients treated with combination therapy received 41.4 or 45 Gy (1.8 Gy/fraction) external beam irradiation followed by a 3- to 5-week break and then received either a 120-Gy 125 I or a 90-Gy 103 Pd implant. Until November 1994, all patients underwent an 125 I implant after which the isotope selection was based on either Gleason score (Gleason score 2-5: 125 I; Gleason 5-8: 103 Pd) or isotope availability. A matched pair analysis was performed to assess any difference between isotopes. Two hundred twenty-two patients were matched according to Gleason score, prostate-specific antigen (PSA), and stage. PSA relapse-free survival (PSA-RFS) was calculated based on the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus Group definition of failure. Kaplan-Meier actuarial survival curves were compared to assess differences in

  2. Medical physics aspects of ophthalmic brachytherapy

    International Nuclear Information System (INIS)

    Sharma, S.D.; Shanta, A.; Palani Selvam, T.; Tripathi, U.B.; Bhatt, B.C.

    2004-11-01

    Intraocular melanoma is the most common primary malignancy of the eye. Radiation therapy using ophthalmic plaque has proved successful in the management of various ocular lesions. Although a few centres were using 90 Sr/ 90 Y plaques for shallow turtlours some years ago, eye plaque therapy was not a common practice in India. A revived interest in the use of eye plaque therapy and very high cost of imported sources has led to the development and production of 125 I seed sources by the Radiopharmaceuticals Division, BARC. This report presents a brief description on the clinical, dosimetry and radiation safety aspects of 90 Sr/ 90 Y and 106 Ru/ 106 Rh beta ray and 125 I gamma ray eye plaque applicators. This report has been divided in five Sections. Section I presents general introduction of ophthalmic brachytherapy including the structure of a human eye, types of ophthalmic plaques and characteristics of radioisotopes commonly used in such applications. A brief review of sources, applicators and dosimetry of 90 Sr/ 90 Y and 106 Ru/ 106 Rh beta and 125 I gamma ophthalmic plaques are given in Section II and Section III, respectively. Section IV contains the single seed dosimetry data of BARC OcuProsta 125 I seed as well as dosimetry data of typical eye plaques loaded with BARC OcuProsta 125 I seed. Quality assurance and radiation safety aspects of these eye applicators are described in Section V. A proforma of the application required to be filled in by the user institution for obtaining regulatory consent to start eye plaque therapy has also been appended to this report. (author)

  3. A therapeutic gain model for brachytherapy

    International Nuclear Information System (INIS)

    Wigg, D.R.

    2003-01-01

    When treating with continuous irradiation the potential therapeutic gain or loss depends on several treatment, normal tissue and tumour variables. There are similarities between equations defining tissue effects with fractionated treatment and brachytherapy. The former is sensitive to dose per fraction (and incomplete repair for short intervals between treatments) and the later is sensitive to dose rate and continuous repair factors. Because of these similarities, for typical tumours and normal tissues, dose per fraction and dose rates generally work in similar directions. As the dose per fraction or dose rate increases the therapeutic gain falls. With continuous irradiation the dose rates effects are determined by Beta cell kill and hence the absolute value of Beta . Minimal sensitivity occurs at very low and very high dose rates. The magnitude of cell kill also depends on the Continuous Repair Factor (g) which is a function of the treatment time and the Repair Half Time (in hours) of the tissues (Repair Half Time T 1/2Ln(2)/h, when h the Repair Constant). An interactive optimising model has been written to predict the therapeutic gain or loss as the parameter values are varied. This model includes the tumour and normal tissue parameters alpha and beta Gy (or individual values), their Repair Half Times, dose rates and overall treatment time. The model is based on the Linear-Quadratic equation and the Total Effect (TE) method of Thames and Hendry although the Extrapolated Response Dose (ERD) method of Barendsen produces the same results. The model is written so that the gain or loss may be seen when treatment is always to normal tissue tolerance doses. The magnitude of the therapeutic loss as the dose rate increases and its sensitivity to changes in normal tissue and tumour parameter values is clearly demonstrated

  4. Brachytherapy dose measurements in heterogeneous tissues

    International Nuclear Information System (INIS)

    Paiva F, G.; Luvizotto, J.; Salles C, T.; Guimaraes A, P. C.; Dalledone S, P. de T.; Yoriyaz, H.; Rubo, R.

    2014-08-01

    Recently, Beau lieu et al. published an article providing guidance for Model-Based Dose Calculation Algorithms (MBDCAs), where tissue heterogeneity considerations are addressed. It is well-known that T G-43 formalism which considers only water medium is limited and significant dose differences have been found comparing both methodologies. The aim of the present work is to experimentally quantify dose values in heterogeneous medium using different dose measurement methods and techniques and compare them with those obtained with Monte Carlo simulations. Experiments have been performed using a Nucletron micro Selectron-Hdr Ir-192 brachytherapy source and a heterogeneous phantom composed by PMMA and different tissue equivalent cylinders like bone, lungs and muscle. Several dose measurements were obtained using tissue equivalent materials with height 1.8 cm and 4.3 cm positioned between the radiation source and the detectors. Radiochromic films, TLDs and MOSFET S have been used for the dose measurements. Film dosimetry has been performed using two methodologies: a) linearization for dose-response curve based on calibration curves to create a functional form that linearize s the dose response and b) 177 multichannel analysis dosimetry where the multiple color channels are analyzed allowing to address not only disturbances in the measurements caused by thickness variation in the film layer, but also, separate other external influences in the film response. All experiments have been simulated using the MCNP5 Monte Carlo radiation transport code. Comparison of experimental results are in good agreement with calculated dose values with differences less than 6% for almost all cases. (Author)

  5. Brachytherapy dose measurements in heterogeneous tissues

    Energy Technology Data Exchange (ETDEWEB)

    Paiva F, G.; Luvizotto, J.; Salles C, T.; Guimaraes A, P. C.; Dalledone S, P. de T.; Yoriyaz, H. [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Rubo, R., E-mail: gabrielpaivafonseca@gmail.com [Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, 05403-900 Sao Paulo (Brazil)

    2014-08-15

    Recently, Beau lieu et al. published an article providing guidance for Model-Based Dose Calculation Algorithms (MBDCAs), where tissue heterogeneity considerations are addressed. It is well-known that T G-43 formalism which considers only water medium is limited and significant dose differences have been found comparing both methodologies. The aim of the present work is to experimentally quantify dose values in heterogeneous medium using different dose measurement methods and techniques and compare them with those obtained with Monte Carlo simulations. Experiments have been performed using a Nucletron micro Selectron-Hdr Ir-192 brachytherapy source and a heterogeneous phantom composed by PMMA and different tissue equivalent cylinders like bone, lungs and muscle. Several dose measurements were obtained using tissue equivalent materials with height 1.8 cm and 4.3 cm positioned between the radiation source and the detectors. Radiochromic films, TLDs and MOSFET S have been used for the dose measurements. Film dosimetry has been performed using two methodologies: a) linearization for dose-response curve based on calibration curves to create a functional form that linearize s the dose response and b) 177 multichannel analysis dosimetry where the multiple color channels are analyzed allowing to address not only disturbances in the measurements caused by thickness variation in the film layer, but also, separate other external influences in the film response. All experiments have been simulated using the MCNP5 Monte Carlo radiation transport code. Comparison of experimental results are in good agreement with calculated dose values with differences less than 6% for almost all cases. (Author)

  6. Patient effective dose from endovascular brachytherapy with 192Ir Sources

    International Nuclear Information System (INIS)

    Perna, L.; Bianchi, C.; Novario, R.; Nicolini, G.; Tanzi, F.; Conte, L.

    2002-01-01

    The growing use of endovascular brachytherapy has been accompanied by the publication of a large number of studies in several fields, but few studies on patient dose have been found in the literature. Moreover, these studies were carried out on the basis of Monte Carlo simulation. The aim of the present study was to estimate the effective dose to the patient undergoing endovascular brachytherapy treatment with 192 Ir sources, by means of experimental measurements. Two standard treatments were taken into account: an endovascular brachytherapy of the coronary artery corresponding to the activity x time product of 184 GBq.min and an endovascular brachytherapy of the renal artery (898 GBq.min). Experimental assessment was accomplished by thermoluminescence dosemeters positioned in more than 300 measurement points in a properly adapted Rando phantom. A method has been developed to estimate the mean organ doses for all tissues and organs concerned in order to calculate the effective dose associated with intravascular brachytherapy. The normalised organ doses resulting from coronary treatment were 2.4x10 -2 mSv.GBq -1 .min -1 for lung, 0.9x10 -2 mSv.GBq -1 .min -1 for oesophagus and 0.48x10 -2 mSv.GBq -1 .min -1 for bone marrow. During brachytherapy of the renal artery, the corresponding normalised doses were 4.2x10 -2 mSv.GBq -1 .min -1 for colon, 7.8x10 -2 mSv.GBq -1 .min -1 for stomach and 1.7x10 -2 mSv.GBq -1 .min -1 for liver. Coronary treatment involved an effective dose of 0.046 mSv.GBq -1 .min -1 , whereas the treatment of the renal artery resulted in an effective dose of 0.15 mSv.GBq -1 .min -1 ; there were many similarities with data from former studies. Based on these results it can be concluded that the dose level of patients exposed during brachytherapy treatment is low. (author)

  7. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Brandao, Samia de Freitas, E-mail: samiabrandao@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Campos, Tarcisio Passos Ribeiro de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2013-06-15

    Objective: comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and methods: simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results: intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h{sup -1}.p{sup -1}.s, respectively, on the healthy tissue, on the balloon periphery and on the /{sub 1} and /{sub 2} tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h{sup -1}.p{sup -1}.s, respectively on the healthy tissue, on the target tumor and on the /{sub 1} and /{sub 2} infiltration zones. Conclusion: Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones. (author)

  8. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors

    Directory of Open Access Journals (Sweden)

    Samia de Freitas Brandao

    2013-07-01

    Full Text Available Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.

  9. Inverse planning and class solutions for brachytherapy treatment planning

    International Nuclear Information System (INIS)

    Trnkova, P.

    2010-01-01

    Brachytherapy or interventional radiooncology is a method of radiation therapy. It is a method, where a small encapsulated radioactive source is placed near to / in the tumour and therefore delivers high doses directly to the target volume. Organs at risk (OARs) are spared due to the inverse square dose fall-off. In the past years there was a slight stagnation in the development of techniques for brachytherapy treatment. While external beam radiotherapy became more and more sophisticated, in brachytherapy traditional methods have been still used. Recently, 3D imaging was considered also as the modality for brachytherapy and more precise brachytherapy could expand. Nowadays, an image guided brachytherapy is state-of-art in many centres. Integration of imaging methods lead to the dose distribution individually tailored for each patient. Treatment plan optimization is mostly performed manually as an adaptation of a standard loading pattern. Recently, inverse planning approaches have been introduced into brachytherapy. The aim of this doctoral thesis was to analyze inverse planning and to develop concepts how to integrate inverse planning into cervical cancer brachytherapy. First part of the thesis analyzes the Hybrid Inverse treatment Planning and Optimization (HIPO) algorithm and proposes a workflow how to safely work with this algorithm. The problem of inverse planning generally is that only the dose and volume parameters are taken into account and spatial dose distribution is neglected. This fact can lead to unwanted high dose regions in a normal tissue. A unique implementation of HIPO into the treatment planning system using additional features enabled to create treatment plans similar to the plans resulting from manual optimization and to shape the high dose regions inside the CTV. In the second part the HIPO algorithm is compared to the Inverse Planning Simulated Annealing (IPSA) algorithm. IPSA is implemented into the commercial treatment planning system. It

  10. Gadolinium neutron capture brachytherapy (GdNCB), a new treatment method for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Enger, Shirin A.; Rezaei, Arash; Munck af Rosenschoeld, Per; Lundqvist, Hans

    2006-01-01

    Restenosis is a major problem after balloon angioplasty and stent implantation. The aim of this study is to introduce gadolinium neutron capture brachytherapy (GdNCB) as a suitable modality for treatment of stenosis. The utility of GdNCB in intravascular brachytherapy (IVBT) of stent stenosis is investigated by using the GEANT4 and MCNP4B Monte Carlo radiation transport codes. To study capture rate, Kerma, absorbed dose and absorbed dose rate around a Gd-containing stent activated with neutrons, a 30 mm long, 5 mm diameter gadolinium foil is chosen. The input data is a neutron spectrum used for clinical neutron capture therapy in Studsvik, Sweden. Thermal neutron capture in gadolinium yields a spectrum of high-energy gamma photons, which due to the build-up effect gives an almost flat dose delivery pattern to the first 4 mm around the stent. The absorbed dose rate is 1.33 Gy/min, 0.25 mm from the stent surface while the dose to normal tissue is in order of 0.22 Gy/min, i.e., a factor of 6 lower. To spare normal tissue further fractionation of the dose is also possible. The capture rate is relatively high at both ends of the foil. The dose distribution from gamma and charge particle radiation at the edges and inside the stent contributes to a nonuniform dose distribution. This will lead to higher doses to the surrounding tissue and may prevent stent edge and in-stent restenosis. The position of the stent can be verified and corrected by the treatment plan prior to activation. Activation of the stent by an external neutron field can be performed days after catherization when the target cells start to proliferate and can be expected to be more radiation sensitive. Another advantage of the nonradioactive gadolinium stent is the possibility to avoid radiation hazard to personnel

  11. Role of TPS in 125I brachytherapy for orbital tumors

    International Nuclear Information System (INIS)

    Ren Ling; Dai Haojie; Li Quan

    2012-01-01

    Objective: To investigate the role of TPS in 125 I brachytherapy for orbital tumors. Methods: Sixty-six patients with orbital tumor treated with 125 I seeds from 2005 to 2009 were retrospectively analyzed. Forty-three patients were treated using TPS guided brachytherapy and the prescribed dose was 140 Gy. Other 23 patients were treated without TPS but simply implanted with 125 I seeds at 1 cm intervals in parallel with each other intraoperatively. CT and TPS quality verification were performed postoperatively in all patients. Also, CT and (or) MRI examination were performed at 3, 6, 12 and 24 months after brachytherapy for follow-up. χ 2 test and Kaplan-Meier survival analysis with log-rank significance test were used with SPSS 17.0. Results: A total of 1070 125 I seeds were implanted in 66 cases, on average, (16.2 ± 7.3) seeds for each patient. The satisfaction rates of postoperative quality verification in patients with and without TPS pre-plans were 79.07% (34/43) and 43.48% (10/23) respectively (χ 2 =8.542, P=0.003). Ten patients were lost in follow-up. Local recurrence rates in patients with favorable postoperative quality verification were 0 (0/37) in 3 months, 6.25% (2/32) in 6 months, 13.64% (3/22) in 12 months and 3/9 in 24 months respectively, which were significantly different from those (5.26% (1/19), 16.67% (3/18), 30.77% (4/13), 6/6) in the patients with inferior postoperative quality verification (χ 2 =9.017, P=0.0003). Conclusions: TPS plays an important role in 125 I brachytherapy for orbital tumors. Also, postoperative quality verification by TPS may help predict the local recurrence after brachytherapy. (authors)

  12. Results of the intestitial brachytherapy and of the combination external radiation-brachytherapy in 150 patients with carcinoma of the oral tongue and floor of the mouth

    International Nuclear Information System (INIS)

    Sannazzari, G.L.; Negri, G.L.; Ozzello, F.

    1986-01-01

    The authors report their experience on the treatment of carcinoma of the oral tongue and floor of the mouth with interstitial brachytherapy, alone or in conbination with external irradiation. One hundred and fifty patients were treated; among these, 116 with brachytherapy alone, 34 with combined treatment. The five years local control in those patients treated with brachytherapy alone was 72.5% in T1, 61.2% in T2 and 35% in T3; in those patients treated with external irradiation and brachytherapy the global five years control was 42.5%. The global five years survival was 64% in the patients treated with brachytherapy alone 48% in the patients treated with combined therapy

  13. Results of the intestitial brachytherapy and of the combination external radiation-brachytherapy in 150 patients with carcinoma of the oral tongue and floor of the mouth

    Energy Technology Data Exchange (ETDEWEB)

    Sannazzari, G L; Negri, G L; Ozzello, F

    1986-01-01

    The authors report their experience on the treatment of carcinoma of the oral tongue and floor of the mouth with interstitial brachytherapy, alone or in conbination with external irradiation. One hundred and fifty patients were treated; among these, 116 with brachytherapy alone, 34 with combined treatment. The five years local control in those patients treated with brachytherapy alone was 72.5% in T1, 61.2% in T2 and 35% in T3; in those patients treated with external irradiation and brachytherapy the global five years control was 42.5%. The global five years survival was 64% in the patients treated with brachytherapy alone 48% in the patients treated with combined therapy. 42 refs.

  14. Ovarian follicular dynamics and plasma steroid concentrations are not significantly different in ewes given intravaginal sponges containing either 20 or 40 mg of fluorogestone acetate.

    Science.gov (United States)

    Letelier, C A; Contreras-Solis, I; García-Fernández, R A; Ariznavarreta, C; Tresguerres, J A F; Flores, J M; Gonzalez-Bulnes, A

    2009-03-01

    Although various progestagens are often used to induce and synchronize estrus and ovulation in ruminants, concerns regarding residues are the impetus to develop alternative approaches, including reduced doses of progestagens. Therefore, the objective was to determine whether ovarian function was affected by halving the dose of fluorogestone acetate in intravaginal sponges for synchronizing ovulation in sheep during the physiologic breeding season. Twenty Manchega ewes, 4-6-year-old, were randomly allocated to receive an intravaginal sponge containing either 20mg (P20, n=10) or 40 mg of fluorogestone acetate (P40, n=10). Cloprostenol (125 microg) was given at sponge insertion, and all sponges were removed after 6d. Ovarian follicular dynamics (monitored by daily ultrasonography) and other aspects of ovarian function did not differ significantly between the two groups. Ovulatory follicles (OF) grew at a similar growth rate (r=0.62; Pprogesterone concentrations (3.8+/-0.35 ng/mL for P20 and 3.9+/-0.38 ng/mL for P40) were similar. In conclusion, reducing the dose of fluorogestone acetate from 40 to 20mg did not affect significantly ovarian follicular dynamics or other aspects of ovarian function.

  15. Brachytherapy in head and neck cancers; Curietherapie des cancers de la sphere ORL

    Energy Technology Data Exchange (ETDEWEB)

    Mazeron, J.J.; Noel, G.; Simon, J.M.; Racadot, S.; Jauffret, E. [Groupe Hospitalier la Pitie-Salpetriere, Centre des Tumeurs, 75 - Paris (France)

    2003-02-01

    Experience accumulated over several decades with radiation of Head and Neck tumours by irradiation has demonstrated the need for a high tumour dose to achieve local control. With external beam irradiation alone, it is difficult to spare adjacent normal tissues, resulting in undesirable late effects on the salivary glands; mandible, and muscles of mastication. Interstitial implantation is ideally suited to deliver a high dose limited to the volume of the primary tumor, thus minimizing sequels. A large experience has been accumulated with low dose rate (LDR) brachytherapy in treatment of carcinoma of oral cavity, oropharynx, and nasopharynx. Recent analysis of large clinical series provided data indicating that modalities of low dose rate brachytherapy should be optimized in treating these tumors for increasing therapeutic ratio. Low dose rate brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with these two last modalities are discussed regarding to those of low dose rate brachytherapy. (authors)

  16. Primary treatment of endometrial carcinoma with high-dose-rate brachytherapy: results of 12 years of experience with 280 patients

    International Nuclear Information System (INIS)

    Knocke, Tomas H.; Kucera, Herwig; Weidinger, Barbara; Hoeller, Walpurga; Poetter, Richard

    1997-01-01

    Purpose: This study aimed to evaluate the efficacy of high-dose-rate brachytherapy (HDRB) in the primary treatment of endometrial carcinoma. The results of 12 years of experience (1981-1992) covering 280 patients (mean age 72 years) and their follow-up over 10 years (mean 55 months) are reported. Methods and Materials: Staging was based on clinical examination and fractionated curettage. There were 116 patients in clinical Stage Ia, 119 in Stage Ib, 37 in Stage II, and 8 in Stage III. HDRB was performed four to five times (8.5 Gy) with a one-channel intracavitary applicator and one to two times (7 Gy) with an intravaginal cylinder applicator. Overall and disease-specific survival, local control according to stage and histology, and late side effects were analyzed retrospectively (actuarial method). Results: At 5 years, overall survival, disease-specific survival, and local control were 52.7%, 76.6%, and 75.4% (Stage Ia: 63.9%, 84.9%, and 86.0%; Stage Ib: 47.3%, 73.3%, and 68.8%; and Stage II: 40.2%, 68.6%, and 60.5%) according to histopathologic Grade 1: 65.1%, 83.5%, and 77.7%; for Grade 2: 44.7%, 75.4%, and 75.8%; and for Grade 3: 37.7%, 63.9%, and 74.1%. Eight patients showed progressive disease, 64 developed recurrence after a median of 13 months (45 of whom had a local recurrence only, and 6 of whom had a local recurrence with distant metastases), 6 developed a lymph node recurrence only, and 7 developed distant metastases only. The calculated probability for developing a Grade III late side effect was 5.2% at 5 years. Conclusion: At Stages Ia, Ib, and II in endometrial carcinoma, HDRB is a very effective treatment modality with acceptable local control rates and disease-specific survival for patients who are not fit for surgery. During the time frame of 12 years and in 280 patients the method has proven to have a low risk of acute complications and an acceptable risk of long-term side effects

  17. Gold nanoparticle-aided brachytherapy with vascular dose painting: estimation of dose enhancement to the tumor endothelial cell nucleus.

    Science.gov (United States)

    Ngwa, Wilfred; Makrigiorgos, G Mike; Berbeco, Ross I

    2012-01-01

    Theoretical microdosimetry at the subcellular level is employed in this study to estimate the dose enhancement to tumor endothelial cell nuclei, caused by radiation-induced photo/Auger electrons originating from gold nanoparticles (AuNPs) targeting the tumor endothelium, during brachytherapy. A tumor vascular endothelial cell (EC) is modeled as a slab of 2 μm (thickness) × 10 μm (length) × 10 μm (width). The EC contains a nucleus of 5 μm diameter and thickness of 0.5-1 μm, corresponding to nucleus size 5%-10% of cellular volume, respectively. Analytic calculations based on the electron energy loss formula of Cole were carried out to estimate the dose enhancement to the nucleus caused by photo/Auger electrons from AuNPs attached to the exterior surface of the EC. The nucleus dose enhancement factor (nDEF), representing the ratio of the dose to the nucleus with and without the presence of gold nanoparticles was calculated for different AuNP local concentrations. The investigated concentration range considers the potential for significantly higher local concentration near the EC due to preferential accumulation of AuNP in the tumor vasculature. Four brachytherapy sources: I-125, Pd-103, Yb-169, and 50 kVp x-rays were investigated. For nucleus size of 10% of the cellular volume and AuNP concentrations ranging from 7 to 140 mg/g, brachytherapy sources Pd-103, I-125, 50 kVp, and Yb-169 yielded nDEF values of 5.6-73, 4.8-58.3, 4.7-56.6, and 3.2-25.8, respectively. Meanwhile, for nucleus size 5% of the cellular volume in the same concentration range, Pd-103, I-125, 50 kVp, and Yb-169 yielded nDEF values of 6.9-79.2, 5.1-63.2, 5.0-61.5, and 3.3-28.3, respectively. The results predict that a substantial dose boost to the nucleus of endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs in combination with brachytherapy. Such vascular dose boosts could induce tumor vascular shutdown, prompting extensive tumor cell death.

  18. Gold nanoparticle-aided brachytherapy with vascular dose painting: Estimation of dose enhancement to the tumor endothelial cell nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Ngwa, Wilfred; Makrigiorgos, G. Mike; Berbeco, Ross I. [Department of Radiation Oncology, Division of Medical Physics and Biophysics, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2012-01-15

    Purpose: Theoretical microdosimetry at the subcellular level is employed in this study to estimate the dose enhancement to tumor endothelial cell nuclei, caused by radiation-induced photo/Auger electrons originating from gold nanoparticles (AuNPs) targeting the tumor endothelium, during brachytherapy. Methods: A tumor vascular endothelial cell (EC) is modeled as a slab of 2 {mu}m (thickness) x 10 {mu}m (length) x 10 {mu}m (width). The EC contains a nucleus of 5 {mu}m diameter and thickness of 0.5-1 {mu}m, corresponding to nucleus size 5%-10% of cellular volume, respectively. Analytic calculations based on the electron energy loss formula of Cole were carried out to estimate the dose enhancement to the nucleus caused by photo/Auger electrons from AuNPs attached to the exterior surface of the EC. The nucleus dose enhancement factor (nDEF), representing the ratio of the dose to the nucleus with and without the presence of gold nanoparticles was calculated for different AuNP local concentrations. The investigated concentration range considers the potential for significantly higher local concentration near the EC due to preferential accumulation of AuNP in the tumor vasculature. Four brachytherapy sources: I-125, Pd-103, Yb-169, and 50 kVp x-rays were investigated. Results: For nucleus size of 10% of the cellular volume and AuNP concentrations ranging from 7 to 140 mg/g, brachytherapy sources Pd-103, I-125, 50 kVp, and Yb-169 yielded nDEF values of 5.6-73, 4.8-58.3, 4.7-56.6, and 3.2-25.8, respectively. Meanwhile, for nucleus size 5% of the cellular volume in the same concentration range, Pd-103, I-125, 50 kVp, and Yb-169 yielded nDEF values of 6.9-79.2, 5.1-63.2, 5.0-61.5, and 3.3-28.3, respectively. Conclusions: The results predict that a substantial dose boost to the nucleus of endothelial cells can be achieved by applying tumor vasculature-targeted AuNPs in combination with brachytherapy. Such vascular dose boosts could induce tumor vascular shutdown, prompting

  19. EVALUACIÓN DE PROGESTERONA INTRAVAGINAL POST INSEMINACIÓN ARTIFICIAL PARA REDUCIR LA MUERTE EMBRIONARIA EN VACAS

    Directory of Open Access Journals (Sweden)

    Jorge Ignacio Macias

    2014-06-01

    Full Text Available El objetivo de esta investigación fue evaluar el efecto de la administración de un dispositivo intravaginal de progesterona post IATF sobre la reducción de la muerte embrionaria, el cual se aplicó siete días después de la inseminación. Se utilizaron 40 vacas de aptitud cárnica de cruza mestiza Senangus x Brahman de dos-cuatro partos. Se realizó ecografía transrectal (Aquilla Vet 7.5 MHZ previo a la sincronización. Se efectuó el inicio de ésta con el dispositivo CIDR 1.38 g progesterona. Después de siete días de la inseminación se colocó el dispositivo usado a 20 animales tratamiento y se lo mantuvo durante 10 días. Se realizó tomas de muestras de sangre para medir los niveles de P4. Estas fueron tomadas a cinco animales del grupo tratamiento en el día que se reinsertó el dispositivo, 5 días después y al retiro. Las muestras revelaron niveles altos de progesterona que oscilaron entre 7.87 hasta 19.4 ng/mL. Se diagnosticó gestación a los 30 y 60 días. Se realizó un análisis costo beneficio al tratamiento. En los resultados se encontró una relación entre los tratamientos y la preñez a los 30 días (p=0.053; la relación del costo beneficio se manifestó económicamente viable con la aplicación de progesterona, ya que por cada dólar invertido se genera como ganancia 23 ctvs de dólar. Se concluye que la aplicación de progesterona reduce la muerte embrionaria hasta los 30 días post inseminación.

  20. Utilization of prostate brachytherapy for low risk prostate cancer: Is the decline overstated?

    OpenAIRE

    Joseph Safdieh; Andrew Wong; Joseph P. Weiner; David Schwartz; David Schreiber

    2016-01-01

    Purpose : Several prior studies have suggested that brachytherapy utilization has markedly decreased, coinciding with the recent increased utilization of intensity modulated radiation therapy, as well as an increase in urologist-owned centers. We sought to investigate the brachytherapy utilization in a large, hospital-based registry. Material and methods: Men with prostate cancer diagnosed between 2004-2012 and treated with either external beam radiation and/or prostate brachytherapy ...

  1. Toward a 'all high rate' brachytherapy: organisation, biology and perspectives after treatment of 192 patients

    International Nuclear Information System (INIS)

    Hannoun-Levi, J.M.; Ferre, M.; Gautier, M.; Marcie, S.

    2007-01-01

    As a result of radiation protection regulations aimed at reducing the exposure to ionizing radiation from care-givers, low dose rate brachytherapy is usually replaced by a pulsed rate brachytherapy. The center Antoine Lacassagne has directed the outset to the use of a high-dose rate brachytherapy. The implications in terms of organization, biology and the prospects for such a change are the principal questions studied. (N.C.)

  2. Development of a irradiator for brachytherapy: preliminary evaluation of accuracy and repeatability; Desenvolvimento de um irradiador para braquiterapia: avaliacao preliminar de precisao e repetibilidade

    Energy Technology Data Exchange (ETDEWEB)

    Damaso, Renato S.; Campos, Tarcisio P.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear]. E-mail: damaso@nuclear.ufmg.br; campos@nuclear.ufmg.br

    2000-07-01

    Brachytherapy is a technique of treatment for cancer which that provides the placement of sources near the tumor region, reducing the exposure of healthy regions. We are developing a project of a irradiator that move several discrete gamma sources assembled on the extremity of flexible shafts. The irradiator has the capacity to achieve the individual placement of the sources automatically, reducing the radiation exposure of the clinical body. The equipment is constituted by a mechanic body which produces the displacement of the shafts, a shielding cylinder repository of sources and electronic system of monitoring and control. The present work illustrates the use of the equipment to simulate the placement of sources foreseen in clinical treatment for cancer by intracavitary or interstitial brachytherapy. Precision and repeatability of placement will be discussed. (author)

  3. Advantages of high-dose rate (HDR) brachytherapy in treatment of prostate cancer

    Science.gov (United States)

    Molokov, A. A.; Vanina, E. A.; Tseluyko, S. S.

    2017-09-01

    One of the modern methods of preserving organs radiation treatment is brachytherapy. This article analyzes the results of prostate brachytherapy. These studies of the advantages of high dose brachytherapy lead to the conclusion that this method of radiation treatment for prostate cancer has a favorable advantage in comparison with remote sensing methods, and is competitive, preserving organs in comparison to surgical methods of treatment. The use of the method of polyfocal transperineal biopsy during the brachytherapy session provides information on the volumetric spread of prostate cancer and adjust the dosimetry plan taking into account the obtained data.

  4. Image guided, adaptive, accelerated, high dose brachytherapy as model for advanced small volume radiotherapy

    International Nuclear Information System (INIS)

    Haie-Meder, Christine; Siebert, Frank-Andre; Poetter, Richard

    2011-01-01

    Brachytherapy has consistently provided a very conformal radiation therapy modality. Over the last two decades this has been associated with significant improvements in imaging for brachytherapy applications (prostate, gynecology), resulting in many positive advances in treatment planning, application techniques and clinical outcome. This is emphasized by the increased use of brachytherapy in Europe with gynecology as continuous basis and prostate and breast as more recently growing fields. Image guidance enables exact knowledge of the applicator together with improved visualization of tumor and target volumes as well as of organs at risk providing the basis for very individualized 3D and 4D treatment planning. In this commentary the most important recent developments in prostate, gynecological and breast brachytherapy are reviewed, with a focus on European recent and current research aiming at the definition of areas for important future research. Moreover the positive impact of GEC-ESTRO recommendations and the highlights of brachytherapy physics are discussed what altogether presents a full overview of modern image guided brachytherapy. An overview is finally provided on past and current international brachytherapy publications focusing on 'Radiotherapy and Oncology'. These data show tremendous increase in almost all research areas over the last three decades strongly influenced recently by translational research in regard to imaging and technology. In order to provide high level clinical evidence for future brachytherapy practice the strong need for comprehensive prospective clinical research addressing brachytherapy issues is high-lighted.

  5. dose in cervical cancer intracavitary brachytherapy

    Directory of Open Access Journals (Sweden)

    Zahra Siavashpour

    2016-04-01

    Full Text Available Purpose: To analyze the optimum organ filling point for organs at risk (OARs dose in cervical cancer high-dose-rate (HDR brachytherapy. Material and methods : In a retrospective study, 32 locally advanced cervical cancer patients (97 insertions who were treated with 3D conformal external beam radiation therapy (EBRT and concurrent chemotherapy during 2010-2013 were included. Rotterdam HDR tandem-ovoid applicators were used and computed tomography (CT scanning was performed after each insertion. The OARs delineation and GEC-ESTRO-based clinical target volumes (CTVs contouring was followed by 3D forward planning. Then, dose volume histogram (DVH parameters of organs were recorded and patients were classified based on their OARs volumes, as well as their inserted tandem length. Results : The absorbed dose to point A ranged between 6.5-7.5 Gy. D 0.1cm ³ and D 2cm ³ of the bladder significantly increased with the bladder volume enlargement (p value < 0.05. By increasing the bladder volume up to about 140 cm3, the rectum dose was also increased. For the cases with bladder volumes higher than 140 cm3, the rectum dose decreased. For bladder volumes lower than 75 cm3, the sigmoid dose decreased; however, for bladder volumes higher than 75 cm3, the sigmoid dose increased. The D 2cm ³ of the bladder and rectum were higher for longer tandems than for shorter ones, respectively. The divergence of the obtained results for different tandem lengths became wider by the extension of the bladder volume. The rectum and sigmoid volume had a direct impact on increasing their D 0.1cm ³ and D 2cm ³, as well as decreasing their D 10 , D 30 , and D 50 . Conclusions : There is a relationship between the volumes of OARs and their received doses. Selecting a bladder with a volume of about 70 cm3 or less proved to be better with regards to the dose to the bladder, rectum, and sigmoid.

  6. Brachytherapy radiation doses to the neurovascular bundles

    International Nuclear Information System (INIS)

    Di Biase, Steven J.; Wallner, Kent; Tralins, Kevin; Sutlief, Steven

    2000-01-01

    Purpose: To investigate the role of radiation dose to the neurovascular bundles (NVB) in brachytherapy-related impotence. Methods and Materials: Fourteen Pd-103 or I-125 implant patients were studied. For patients treated with implant alone, the prostate and margin (clinical target volume [CTV]) received a prescription dose of 144 Gy for I-125 or 115 Gy for Pd-103. Two patients received Pd-103 (90 Gy) with 46 Gy supplemental external beam radiation (EBRT). Axial CT images were acquired 2 to 4 hours postoperatively for postimplant dosimetry. Because the NVBs cannot be visualized on CT, NVB calculation points were determined according to previously published anatomic descriptions. Bilateral NVB points were considered to lie posterior-laterally, approximately 2 mm from the prostatic capsule. NVB doses were recorded bilaterally, at 0.5-cm intervals from the prostatic base. Results: For Pd-103, the average NVB doses ranged from 150 Gy to 260 Gy, or 130% to 226% of the prescription dose. For I-125, the average NVB dose ranged from 200 Gy to 325 Gy, or 140% to 225% of the prescription dose. These was no consistent relationship between the NVB dose and the distance from the prostatic base. To examine the possible effect of minor deviations of our calculation points from the true NVB location, we performed NVB calculations at points 2 mm medial or lateral from the NVB calculation point in 8 patients. Doses at these alternate calculation points were comparable, although there was greater variability with small changes in the calculation point if sources were located outside the capsule, near the NVB calculation point. Three patients who developed early postimplant impotence had maximal NVB doses that far exceeded the average values. Conclusions: In the next few years, we hope to clarify the role of high NVB radiation doses on potency, by correlating NVB dose calculations with a large number of patients enrolled in an ongoing I-125 versus Pd-103 trial for early-stage patients

  7. Conformational episcleral brachytherapy in ocular tumors

    International Nuclear Information System (INIS)

    Goset, Karen; Barriga, Hernan; Guevara, Juan; Zelada, Gabriel; Badinez, Leonardo; Gonzalez, German

    2000-01-01

    Brachytherapy with an episcleral plate is an alternative treatment for choroid melanomas and retinoblastomas that allows the sight to be saved. The most common techniques use a metal applicator with beta or Co-60 transmitters, which have a standard geometry, require surgical installation of the active devices and do not allow optimized dosimetry. In 1997, the Clinica Alemana in Santiago, Chile, developed a new device based on the one described by J.P. Gerard (1988), with plastic material, personalized and with delayed charge. Three cases have been treated. Two retinoblastomas: 1) Primary treatment in unilateral Rb, R.E. group II in a 9 month old boy, 2) External post radiotherapy rescue in oculus ultimus by bilateral Rb in a 10 year old girl, and 3) Choroid melanoma T3N0M0 in a 77 year old woman. A personalized applicator was prepared in each case depending on the size and location of the tumor. The distribution of the vector catheters was designed following the Paris system standards. The applicator was inserted in the operating room, under general anesthesia by a team of trained ophthalmologists. An X-ray and helichoidal simulation scan were taken with fictitious sources. Previsional dosimetry was undertaken, with evaluation of the dosage to the tumor apex, crystalline lens, sclera and optic nerve. Prolonged activation with low level dosage Ir-192 wires was performed in a protected room. When the programmed dosage was completed, the sources and then the inactive applicator were removed. Dosage: A 40 Gy dose was applied in the retinoblastoma to the tumor apex and 60 Gy to the melanoma, over a 2 to 3 day period. Tolerance was excellent, there were no incidents or acute complications. The retinoblastomas fully regressed in 1 to 2 weeks, with no local relapse or after affects after 2, 4 and 6 months of follow-up. The 3 patients have retained their sight. The development of this technique is feasible and with enough resources, relatively easy to implement. It has

  8. Dosimetric comparison between intensity modulated brachytherapy versus external beam intensity modulated radiotherapy for cervix cancer: a treatment planning study

    International Nuclear Information System (INIS)

    Subramani, V.; Sharma, D.N.; Jothy Basu, K.S.; Rath, G.K.; Gopishankar, N.

    2008-01-01

    To evaluate the dosimetric superiority of intensity modulated brachytherapy (IMBT) based on inverse planning optimization technique with classical brachytherapy optimization and also with external beam intensity modulated radiotherapy planning technique in patients of cervical carcinoma

  9. Nanoparticle-Based Brachytherapy Spacers for Delivery of Localized Combined Chemoradiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rajiv, E-mail: r.kumar@neu.edu [Nanomedicine Science and Technology Center, Northeastern University, Boston, Massachusetts (United States); Department of Radiation Oncology, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts (United States); Belz, Jodi [Nanomedicine Science and Technology Center, Northeastern University, Boston, Massachusetts (United States); Markovic, Stacey [Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts (United States); Jadhav, Tej; Fowle, William [Nanomedicine Science and Technology Center, Northeastern University, Boston, Massachusetts (United States); Niedre, Mark [Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts (United States); Cormack, Robert; Makrigiorgos, Mike G. [Department of Radiation Oncology, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts (United States); Sridhar, Srinivas [Nanomedicine Science and Technology Center, Northeastern University, Boston, Massachusetts (United States); Department of Radiation Oncology, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts (United States)

    2015-02-01

    Purpose: In radiation therapy (RT), brachytherapy-inert source spacers are commonly used in clinical practice to achieve high spatial accuracy. These implanted devices are critical technical components of precise radiation delivery but provide no direct therapeutic benefits. Methods and Materials: Here we have fabricated implantable nanoplatforms or chemoradiation therapy (INCeRT) spacers loaded with silica nanoparticles (SNPs) conjugated containing a drug, to act as a slow-release drug depot for simultaneous localized chemoradiation therapy. The spacers are made of poly(lactic-co-glycolic) acid (PLGA) as matrix and are physically identical in size to the commercially available brachytherapy spacers (5 mm × 0.8 mm). The silica nanoparticles, 250 nm in diameter, were conjugated with near infrared fluorophore Cy7.5 as a model drug, and the INCeRT spacers were characterized in terms of size, morphology, and composition using different instrumentation techniques. The spacers were further doped with an anticancer drug, docetaxel. We evaluated the in vivo stability, biocompatibility, and biodegradation of these spacers in live mouse tissues. Results: The electron microscopy studies showed that nanoparticles were distributed throughout the spacers. These INCeRT spacers remained stable and can be tracked by the use of optical fluorescence. In vivo optical imaging studies showed a slow diffusion of nanoparticles from the spacer to the adjacent tissue in contrast to the control Cy7.5-PLGA spacer, which showed rapid disintegration in a few days with a burst release of Cy7.5. The docetaxel spacers showed suppression of tumor growth in contrast to control mice over 16 days. Conclusions: The imaging with the Cy7.5 spacer and therapeutic efficacy with docetaxel spacers supports the hypothesis that INCeRT spacers can be used for delivering the drugs in a slow, sustained manner in conjunction with brachytherapy, in contrast to the rapid clearance of the drugs when

  10. Nanoparticle-Based Brachytherapy Spacers for Delivery of Localized Combined Chemoradiation Therapy

    International Nuclear Information System (INIS)

    Kumar, Rajiv; Belz, Jodi; Markovic, Stacey; Jadhav, Tej; Fowle, William; Niedre, Mark; Cormack, Robert; Makrigiorgos, Mike G.; Sridhar, Srinivas

    2015-01-01

    Purpose: In radiation therapy (RT), brachytherapy-inert source spacers are commonly used in clinical practice to achieve high spatial accuracy. These implanted devices are critical technical components of precise radiation delivery but provide no direct therapeutic benefits. Methods and Materials: Here we have fabricated implantable nanoplatforms or chemoradiation therapy (INCeRT) spacers loaded with silica nanoparticles (SNPs) conjugated containing a drug, to act as a slow-release drug depot for simultaneous localized chemoradiation therapy. The spacers are made of poly(lactic-co-glycolic) acid (PLGA) as matrix and are physically identical in size to the commercially available brachytherapy spacers (5 mm × 0.8 mm). The silica nanoparticles, 250 nm in diameter, were conjugated with near infrared fluorophore Cy7.5 as a model drug, and the INCeRT spacers were characterized in terms of size, morphology, and composition using different instrumentation techniques. The spacers were further doped with an anticancer drug, docetaxel. We evaluated the in vivo stability, biocompatibility, and biodegradation of these spacers in live mouse tissues. Results: The electron microscopy studies showed that nanoparticles were distributed throughout the spacers. These INCeRT spacers remained stable and can be tracked by the use of optical fluorescence. In vivo optical imaging studies showed a slow diffusion of nanoparticles from the spacer to the adjacent tissue in contrast to the control Cy7.5-PLGA spacer, which showed rapid disintegration in a few days with a burst release of Cy7.5. The docetaxel spacers showed suppression of tumor growth in contrast to control mice over 16 days. Conclusions: The imaging with the Cy7.5 spacer and therapeutic efficacy with docetaxel spacers supports the hypothesis that INCeRT spacers can be used for delivering the drugs in a slow, sustained manner in conjunction with brachytherapy, in contrast to the rapid clearance of the drugs when

  11. Air core detectors for Cerenkov-free scintillation dosimetry of brachytherapy β-sources.

    Science.gov (United States)

    Eichmann, Marion; Thomann, Benedikt

    2017-09-01

    Plastic scintillation detectors are used for dosimetry in small radiation fields with high dose gradients, e.g., provided by β-emitting sources like 106 Ru/ 106 Rh eye plaques. A drawback is a background signal caused by Cerenkov radiation generated by electrons passing the optical fibers (light guides) of this dosimetry system. Common approaches to correct for the Cerenkov signal are influenced by uncertainties resulting from detector positioning and calibration procedures. A different approach to avoid any correction procedure is to suppress the Cerenkov signal by replacing the solid core optical fiber with an air core light guide, previously shown for external beam therapy. In this study, the air core concept is modified and applied to the requirements of dosimetry in brachytherapy, proving its usability for measuring water energy doses in small radiation fields. Three air core detectors with different air core lengths are constructed and their performance in dosimetry for brachytherapy β-sources is compared with a standard two-fiber system, which uses a second fiber for Cerenkov correction. The detector systems are calibrated with a 90 Sr/ 90 Y secondary standard and tested for their angular dependence as well as their performance in depth dose measurements of 106 Ru/ 106 Rh sources. The signal loss relative to the standard detector increases with increasing air core length to a maximum value of 58.3%. At the same time, however, the percentage amount of Cerenkov light in the total signal is reduced from at least 12.1% to a value below 1.1%. There is a linear correlation between induced dose and measured signal current. The air core detectors determine the dose rates for 106 Ru/ 106 Rh sources without any form of correction for the Cerenkov signal. The air core detectors show advantages over the standard two-fiber system especially when measuring in radiation fields with high dose gradients. They can be used as simple one-fiber systems and allow for an almost

  12. Trends in the Utilization of Brachytherapy in Cervical Cancer in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kathy, E-mail: Kathy.Han@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, Ontario (Canada); Milosevic, Michael; Fyles, Anthony [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, Ontario (Canada); Pintilie, Melania [Department of Biostatistics, Princess Margaret Hospital, Toronto, Ontario (Canada); Viswanathan, Akila N. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, Massachusetts (United States)

    2013-09-01

    Purpose: To determine the trends in brachytherapy use in cervical cancer in the United States and to identify factors and survival benefits associated with brachytherapy treatment. Methods and Materials: Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 7359 patients with stages IB2-IVA cervical cancer treated with external beam radiation therapy (EBRT) between 1988 and 2009. Propensity score matching was used to adjust for differences between patients who received brachytherapy and those who did not from 2000 onward (after the National Cancer Institute alert recommending concurrent chemotherapy). Results: Sixty-three percent of the 7359 women received brachytherapy in combination with EBRT, and 37% received EBRT alone. The brachytherapy utilization rate has decreased from 83% in 1988 to 58% in 2009 (P<.001), with a sharp decline of 23% in 2003 to 43%. Factors associated with higher odds of brachytherapy use include younger age, married (vs single) patients, earlier years of diagnosis, earlier stage and certain SEER regions. In the propensity score-matched cohort, brachytherapy treatment was associated with higher 4-year cause-specific survival (CSS; 64.3% vs 51.5%, P<.001) and overall survival (OS; 58.2% vs 46.2%, P<.001). Brachytherapy treatment was independently associated with better CSS (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.57-0.71), and OS (HR 0.66; 95% CI, 0.60 to 0.74). Conclusions: This population-based analysis reveals a concerning decline in brachytherapy utilization and significant geographic disparities in the delivery of brachytherapy in the United States. Brachytherapy use is independently associated with significantly higher CSS and OS and should be implemented in all feasible cases.

  13. Perioperative high dose rate (HDR brachytherapy in unresectable locally advanced pancreatic tumors

    Directory of Open Access Journals (Sweden)

    Brygida Białas

    2011-07-01

    Full Text Available Purpose: The aim of the study was to present an original technique of catheter implantation for perioperative HDR-Ir192 brachytherapy in patients after palliative operations of unresectable locally advanced pancreatic tumors and to estimate the influence of perioperative HDR-Ir192 brachytherapy on pain relief in terminal pancreatic cancer patients. Material and methods: Eight patients with pancreatic tumors located in the head of pancreas underwent palliative operations with the use of HDR-Ir192 brachytherapy. All patients qualified for surgery reported pain of high intensity and had received narcotic painkillers prior to operation. During the last phase of the surgery, the Nucletron® catheters were implanted in patients to prepare them for later perioperative brachytherapy. Since the 6th day after surgery HDR brachytherapy was performed. Before each brachytherapy fraction the location of implants were checked using fluoroscopy. A fractional dose was 5 Gy and a total dose was 20 Gy in the area of radiation. A comparative study of two groups of patients (with and without brachytherapy with stage III pancreatic cancer according to the TNM scale was taken in consideration. Results and Conclusions: The authors claim that the modification of catheter implantation using specially designed cannula, facilitates the process of inserting the catheter into the tumor, shortens the time needed for the procedure, and reduces the risk of complications. Mean survival time was 5.7 months. In the group of performed brachytherapy, the mean survival time was 6.7 months, while in the group of no brachytherapy performed – 4.4 months. In the group of brachytherapy, only one patient increased the dose of painkillers in the last month of his life. Remaining patients took constant doses of medicines. Perioperative HDR-Ir192 brachytherapy could be considered as a practical application of adjuvant therapy for pain relief in patients with an advanced pancreatic cancer.

  14. Evaluation of pregnancy rates of Bos indicus cows subjected to different synchronization ovulation protocols using injectable progesterone or an intravaginal device

    Directory of Open Access Journals (Sweden)

    Jefferson Tadeu Campos

    2016-12-01

    Full Text Available This study evaluated the pregnancy rate in Nelore cows (Bos indicus that were subjected to fixed-time artificial insemination (FTAI using different protocols consisting of injectable progesterone (P4 or an intravaginal device (impregnated with P4. Multiparous cows 72-84 months in age, 30-45 days postpartum, were selected on the basis of the absence of a corpus luteum (CL and follicles < 8 mm after transrectal palpation and ultrasound examinations. On a random day of the estrus cycle (D0, the selected animals (n = 135 were randomly assigned to one of three experimental groups (n = 45 each. Group I (injectable P4/FTAI 36 hours received 250 mg of injectable P4 and 2 mg EB on D0; on D7, they received 500 µg of cloprostenol; on D8, 300 IU of eCG and 1 mg of EB were administered; and finally, FTAI was performed 36 hours after the application of EB. Group II (injectable P4/FTAI 48 hours received the same protocol as Group I, except that the FTAI was performed 48 hours after ovulation induction. The animals of Group III (Control/CIDR received a conventional protocol for FTAI using an intravaginal device (D0: P4 and 2 mg EB; D8: device removal, 500 µg cloprostenol, 300 IU eCG, 1 mg EB; and FTAI performed 48 hours after removal of the device. The results showed that cows synchronized with the conventional protocol for FTAI (Control/CIDR had a higher pregnancy rate (60 %, 27/45 than those synchronized with an injectable P4/FTAI 36 hours (33.33 %; 15/45, P = 0.010. However, the group receiving injectable P4 group/FTAI 48 hours had a similar pregnancy rate (48.9 %; 22/45; P = 0.290 when compared to both the group receiving the conventional protocol and that receiving injectable P4/FTAI 36 hours (P = 0.134. Although the injectable P4 may affect pregnancy rate with the FTAI performed in 36 hours, we found similar pregnancy rates from cows inseminated 48 hours after induction ovulation, considering injectable or intravaginal P4. Therefore, we suggest that

  15. Biomaterial characteristics and application of silicone rubber and PVA hydrogels mimicked in organ groups for prostate brachytherapy.

    Science.gov (United States)

    Li, Pan; Jiang, Shan; Yu, Yan; Yang, Jun; Yang, Zhiyong

    2015-09-01

    It is definite that transparent material with similar structural characteristics and mechanical properties to human tissue is favorable for experimental study of prostate brachytherapy. In this paper, a kind of transparent polyvinyl alcohol (PVA) hydrogel and silicone rubber are developed as suitable substitutions for human soft tissue. Segmentation and 3D reconstruction of medical image are performed to manufacture the mould of organ groups through rapid prototyping technology. Micro-structure observation, force test and CCD deformation test have been conducted to investigate the structure and mechanical properties of PVA hydrogel used in organ group mockup. Scanning electron microscope (SEM) image comparison results show that PVA hydrogel consisting of 3 g PVA, 17 g de-ionized water, 80 g dimethyl-sulfoxide (DMSO), 4 g NaCl, 1.5 g NaOH, 3 g epichlorohydrin (ECH) and 7 freeze/thaw cycles reveals similar micro-structure to human prostate tissue. Through the insertion force comparison between organ group mockup and clinical prostate brachytherapy, PVA hydrogel and silicone rubber are found to have the same mechanical properties as prostate tissue and muscle. CCD deformation test results show that insertion force suffers a sharp decrease and a relaxation of tissue deformation appears when needle punctures the capsule of prostate model. The results exhibit that organ group mockup consisting of PVA hydrogel, silicone rubber, membrane and agarose satisfies the needs of prostate brachytherapy simulation in general and can be used to mimic the soft tissues in pelvic structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Film based verification of calculation algorithms used for brachytherapy planning-getting ready for upcoming challenges of MBDCA

    Directory of Open Access Journals (Sweden)

    Grzegorz Zwierzchowski

    2016-08-01

    Full Text Available Purpose: Well-known defect of TG-43 based algorithms used in brachytherapy is a lack of information about interaction cross-sections, which are determined not only by electron density but also by atomic number. TG-186 recommendations with using of MBDCA (model-based dose calculation algorithm, accurate tissues segmentation, and the structure’s elemental composition continue to create difficulties in brachytherapy dosimetry. For the clinical use of new algorithms, it is necessary to introduce reliable and repeatable methods of treatment planning systems (TPS verification. The aim of this study is the verification of calculation algorithm used in TPS for shielded vaginal applicators as well as developing verification procedures for current and further use, based on the film dosimetry method. Material and methods : Calibration data was collected by separately irradiating 14 sheets of Gafchromic® EBT films with the doses from 0.25 Gy to 8.0 Gy using HDR 192Ir source. Standard vaginal cylinders of three diameters were used in the water phantom. Measurements were performed without any shields and with three shields combination. Gamma analyses were performed using the VeriSoft® package. Results : Calibration curve was determined as third-degree polynomial type. For all used diameters of unshielded cylinder and for all shields combinations, Gamma analysis were performed and showed that over 90% of analyzed points meets Gamma criteria (3%, 3 mm. Conclusions : Gamma analysis showed good agreement between dose distributions calculated using TPS and measured by Gafchromic films, thus showing the viability of using film dosimetry in brachytherapy.

  17. Monte Carlo dosimetric characterization of the Flexisource Co-60 high-dose-rate brachytherapy source using PENELOPE.

    Science.gov (United States)

    Almansa, Julio F; Guerrero, Rafael; Torres, Javier; Lallena, Antonio M

    60 Co sources have been commercialized as an alternative to 192 Ir sources for high-dose-rate (HDR) brachytherapy. One of them is the Flexisource Co-60 HDR source manufactured by Elekta. The only available dosimetric characterization of this source is that of Vijande et al. [J Contemp Brachytherapy 2012; 4:34-44], whose results were not included in the AAPM/ESTRO consensus document. In that work, the dosimetric quantities were calculated as averages of the results obtained with the Geant4 and PENELOPE Monte Carlo (MC) codes, though for other sources, significant differences have been quoted between the values obtained with these two codes. The aim of this work is to perform the dosimetric characterization of the Flexisource Co-60 HDR source using PENELOPE. The MC simulation code PENELOPE (v. 2014) has been used. Following the recommendations of the AAPM/ESTRO report, the radial dose function, the anisotropy function, the air-kerma strength, the dose rate constant, and the absorbed dose rate in water have been calculated. The results we have obtained exceed those of Vijande et al. In particular, the absorbed dose rate constant is ∼0.85% larger. A similar difference is also found in the other dosimetric quantities. The effect of the electrons emitted in the decay of 60 Co, usually neglected in this kind of simulations, is significant up to the distances of 0.25 cm from the source. The systematic and significant differences we have found between PENELOPE results and the average values found by Vijande et al. point out that the dosimetric characterizations carried out with the various MC codes should be provided independently. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  18. Comparison of absorbed dose in the cervix carcinoma therapy by brachytherapy of high dose rate using the conventional planning and Monte Carlo simulation; Comparacao da dose absorvida no tratamento do cancer ginecologico por braquiterapia de alta taxa de dose utilizando o planejamento convencional do tratamento e simulacao de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Aneli Oliveira da

    2010-07-01

    This study aims to compare the doses received for patients submitted to brachytherapy High Dose Rate (HDR) brachytherapy, a method of treatment of the cervix carcinoma, performed in the planning system PLATO BPS with the doses obtained by Monte Carlo simulation using the radiation transport code MCNP 5 and one female anthropomorphic phantom based on voxel, the FAX. The implementation of HDR brachytherapy treatment for the cervix carcinoma consists of the insertion of an intrauterine probe and an intravaginal probe (ring or ovoid) and then two radiographs are obtained, anteroposterior (AP) and lateral (LAT) to confirm the position of the applicators in the patient and to allow the treatment planning and the determination of the absorbed dose at points of interest: rectum, bladder, sigmoid and point A, which corresponds anatomically to the crossings of the uterine arteries with ureters The absorbed doses obtained with the code MCNP 5, with the exception of the absorbed dose in the rectum and sigmoid for the simulation considering a point source of {sup 192}Ir, are lower than the absorbed doses from PLATO BPS calculations because the MCNP 5 considers the chemical compositions and densities of FAX body, not considering the medium as water. When considering the Monte Carlo simulation for a source with dimensions equal to that used in the brachytherapy irradiator used in this study, the values of calculated absorbed dose to the bladder, to the rectum, to the right point A and to the left point A were respectively lower than those determined by the treatment planning system in 33.29, 5.01, 22.93 and 19.04%. These values are almost all larger than the maximum acceptable deviation between patient planned and administered doses (5 %). With regard to the rectum and bladder, which are organs that must be protected, the present results are in favor of the radiological protection of patients. The point A, that is on the isodose of 100%, used to tumor treatment, the results

  19. Routine quality control of high dose rate brachytherapy equipment

    International Nuclear Information System (INIS)

    Guzman Calcina, Carmen S.; Almeida, Adelaide de; Rocha, Jose R. Oliveira

    2001-01-01

    A Quality Assurance program should be installed also for High Dose Rate brachytherapy, in the order to achieve a correct dose administration to the patient and for the safety to those involved directly with the treatment. The work presented here has the following purposes: Analyze the types of equipment tests presented by the official protocols (TG40, TG56 e ARCAL XXX), evaluate the brachytherapy routine tests of protocols from various national and international radiotherapy services and compare the latter with those presented in the official protocols. As a result, we conclude the following: TG56 presents a higher number of tests when compared to the other official protocols and most of the tests presented by the analyzed services are present in TG56. A suggestion for a basic protocol is presented, emphasizing the periodicity and tolerance level of each of the tests. (author)

  20. Brachytherapy: The need for a national metrology lab in Spain

    International Nuclear Information System (INIS)

    Aviles Lucas, P.

    2011-01-01

    Radiotherapy, along with chemotherapy and surgery, is an essential therapeutic technique for treating malignant tumours. Part of the challenge of a suitable radiotherapy treatment lies on the optimisation of the irradiated volume, which must be adapted to the tumour volume as far as possible. Depending on position of the radiation source relative to the patient, the procedure in question could be external radiotherapy, or brachytherapy. In a brachytherapy procedure, relatively small encapsulated radioactive sources are placed close to or in the tumour volume to be treated. This therapeutic treatment has two obvious advantages; on one hand the prescribed dose can be adjusted to the tumour volume, preventing unnecessary exposure of the adjacent healthy tissues, and on the other, it decreases the treatment duration compared to a radiotherapy treatment. (Author) 19 refs.

  1. Ultrasonography-guided cobalt-60 brachytherapy for malignant glioma

    International Nuclear Information System (INIS)

    Sakai, Noboru; Takenaka, Katsunobu; Ueda, Tatsuya

    1989-01-01

    Brachytherapy with cobalt-60 source is reported. In this method it is characterized that the source is inserted interstitially with remote control system by after-loading method via outer catheter (using tandem tube), which was established in the center of residual tumor, using ultrasonography guide with trepanation, or intraoperatively put within the dead space after tumor resection. Six cases of deep-seated and recurrent malignant glioma, were treated with this method. A total dose of 20 to 45 Gy (10 to 15 Gy/day for 2 to 3 days) was delivered to the target. Additionally conventional external irradiation was followed. The effect of cobalt-60 brachytherapy on such tumors were favorable especially for well-circumscribed glioma less than 3 cm on CT scan. (author)

  2. Dose calculation and isodose curves determination in brachytherapy

    International Nuclear Information System (INIS)

    Maranhao, Frederico B.; Lima, Fernando R.A.; Khoury, Helen J.

    2000-01-01

    Brachytherapy is a form of cancer treatment in which small radioactive sources are placed inside of, or close to small tumors, in order to cause tissue necrosis and, consequently, to interrupt the tumor growth process. A very important aspect to the planning of this therapy is the calculation of dose distributions in the tumor and nearby tissues, to avoid the unnecessary irradiation of healthy tissue. The objective of this work is to develop a computer program that will permit treatment planning for brachytherapy at low dose rates, minimizing the possible errors introduced when such calculations are done manually. Results obtained showed good agreement with those from programs such as BRA, which is widely used in medical practice. (author)

  3. Cervical cancer. Application of MR imaging in brachytherapy

    International Nuclear Information System (INIS)

    Ebe, Kazuyu; Matsunaga, Naofumi

    1996-01-01

    For the purpose of application of MRI in arrangement of brachytherapy of cervical cancer, a method was proposed to see the radiation doses in surrounding tissues by superimposing the dose distribution pattern of the radiation source on the MR image. The applicator for the source was filled with water to get its T2-weighted image and was inserted in the patients. The MRI apparatus was Siemens Magnetom Vision (1.5T) with phased array coil. T2-weighted sagittal and coronary images were taken by turbospin echo and HASTE methods. The section thickness was 5 mm. The dose distribution pattern was superimposed on the frontal and lateral images by Siemens Mevaplan to see the doses in surrounding tissues. In 4 patients, it was possible to estimate the radiation dose in the posterior wall of bladder, anterior wall of rectum and urinary duct. The method is promising for arranging brachytherapy of cervical cancer. (K.H.)

  4. Brachytherapy for coronary restenosis: state of art in 2003

    International Nuclear Information System (INIS)

    Latorzeff, I.; Delannes, M.; Latorzeff, I.; Carrie, D.; Alibelli, M.J.; Bonnet, J.; Duthil, P.

    2003-01-01

    Based on therapeutic approach for benign diseases, vascular brachytherapy decreases smooth vascular muscle cells proliferation and multiplication which lead to the formation of the neo-intima. The radioactive positive action affects arterial recoil due to post angioplasty vessel injury. Randomized studies has shown good angiographic results up to 6 months of follow-up, with 50% in-stent restenosis rate decrease and on the analysed segment as well. Decrease on Mace and TLR show statistically significance. Results don't correlate with emitter and beta emitters had been introduced in France recently. Vascular brachytherapy is actually indicated for in-stent restenosis, there is no evidence to perform this treatment for de novo lesion. Geographic miss, source centering, late thrombosis and pullback procedure may interfere with treatment quality. IVUS allows best target volume determination to a higher quality level. Internationals guidelines such as Eva-Gec-Estro recommendations could increase treatment safety and enable development of an optimal technique. (authors)

  5. Brachytherapy for prostate cancer: Comparative characteristics of procedures

    Directory of Open Access Journals (Sweden)

    S. V. Kanaev

    2015-01-01

    Full Text Available The introduction of interstitial radiation sources is the «youngest» of the radical method of treatment of patients with prostate cancer (PC. The high level of efficiency comparable to prostatectomy at a significantly lower rate of complications causes rapid growth of clinical use of brachytherapy (BT. Depending on the radiation source and the mode of administration into the prostate gland are two types BT – high-dose rate (temporary (HDR-BT and low-dose rate (permanent (LDR-BT brachytherapy. At the heart of these two methods are based on a single principle of direct effect of the quantum gamma radiation on the area of interest. However, the differences between the characteristics of isotopes used and technical aspects of the techniques cause the difference in performance and complication rates for expression HDR-BT and LDR-BT.

  6. Circulating progesterone concentrations in nonlactating Holstein cows during reuse of intravaginal progesterone implants sanitized by autoclave or chemical disinfection.

    Science.gov (United States)

    Melo, L F; Monteiro, P L J; Oliveira, L H; Guardieiro, M M; Drum, J N; Wiltbank, M C; Sartori, R

    2018-04-01

    The aim of this study was to compare plasma progesterone (P4) concentrations in nonlactating, multiparous Holstein cows (n = 24) treated with 2 types of intravaginal implants containing either 1.0 or 1.9 g of P4 either at the first use or during reuse of the implants after sanitizing the implant by autoclave or chemical disinfection. In a completely randomized design with a 2 × 3 factorial arrangement and 2 replicates, every cow underwent 2 of 6 treatments. Two sources of P4 [controlled internal drug release (1.9 g of P4) from Zoetis (São Paulo, Brazil), and Sincrogest (1.0 g of P4) from Ourofino (Cravinhos, Brazil)] and 3 types of processing, new (N), reused after autoclave (RA), and reused after chemical disinfection (RC), were used. After inducing luteolysis to avoid endogenous circulating P4, the cows were randomized in 1 of 6 treatments (1.9 g of N, 1.9 g of RA, 1.9 g of RC, 1.0 g of N, 1.0 g of RA, and 1.0 g RC). Cows were treated with the implants for 8 d and during this period blood samples were collected at 0, 2, 12, 24, 48, 72, 96, 120, 144, 168, and 192 h. Statistical analyses were performed using Proc-Mixed and the mean ± standard error of the mean P4 concentrations were calculated using the Proc-Means procedures of SAS 9.4 (SAS Institute Inc., Cary, NC). No interaction between treatments was observed. Comparing types of implant, average P4 concentrations during treatments were greater for 1.9 g than 1.0 g (1.46 vs. 1.14 ± 0.04 ng/mL). When types of processing were compared, average P4 concentrations did not differ between autoclaved and new inserts (1.46 vs. 1.37 ± 0.05 ng/mL; respectively), but both were greater than chemically disinfected implants (1.09 ± 0.04 ng/mL). Within 1.9-g P4 inserts, P4 concentrations from autoclaved implants were greater than new, which were greater than chemically disinfected (1.67 ± 0.06 vs. 1.49 ± 0.07 vs. 1.21 ± 0.05 ng/mL; respectively). For 1.0-g P4 implants, P4 concentrations from autoclaved did not differ

  7. Photon energy-fluence correction factor in low energy brachytherapy

    International Nuclear Information System (INIS)

    Antunes, Paula C.G.; Yoriyaz, Hélio; Vijande, Javier; Giménez-Alventosa, Vicent; Ballester, Facundo

    2017-01-01

    The AAPM TG-43 brachytherapy dosimetry formalism has become a standard for brachytherapy dosimetry worldwide; it implicitly assumes that charged-particle equilibrium (CPE) exists for the determination of absorbed dose to water at different locations. At the time of relating dose to tissue and dose to water, or vice versa, it is usually assumed that the photon fluence in water and in tissues are practically identical, so that the absorbed dose in the two media can be related by their ratio of mass energy-absorption coefficients. The purpose of this work is to study the influence of photon energy-fluence in different media and to evaluate a proposal for energy-fluence correction factors for the conversion between dose-to-tissue (D tis ) and dose-to-water (D w ). State-of-the art Monte Carlo (MC) calculations are used to score photon fluence differential in energy in water and in various human tissues (muscle, adipose and bone) in two different codes, MCNP and PENELOPE, which in all cases include a realistic modeling of the 125 I low-energy brachytherapy seed in order to benchmark the formalism proposed. A correction is introduced that is based on the ratio of the water-to-tissue photon energy-fluences using the large-cavity theory. In this work, an efficient way to correlate absorbed dose to water and absorbed dose to tissue in brachytherapy calculations at clinically relevant distances for low-energy photon emitting seed is proposed. The energy-fluence based corrections given in this work are able to correlate absorbed dose to tissue and absorbed dose to water with an accuracy better than 0.5% in the most critical cases. (author)

  8. Brachytherapy in Lip Carcinoma: Long-Term Results

    Energy Technology Data Exchange (ETDEWEB)

    Guibert, Mireille, E-mail: mireilleguib@voila.fr [Department of Head and Neck Surgery, Larrey Hospital, Toulouse (France); David, Isabelle [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France); Vergez, Sebastien [Department of Head and Neck Surgery, Larrey Hospital, Toulouse (France); Rives, Michel [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France); Filleron, Thomas [Department of Epidemiology, Claudius Regaud Institut, Toulouse (France); Bonnet, Jacques; Delannes, Martine [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France)

    2011-12-01

    Purpose: The aim of this study was to evaluate the effectiveness of low-dose-rate brachytherapy for local control and relapse-free survival in squamous cell and basal cell carcinomas of the lips. We compared two groups: one with tumors on the skin and the other with tumors on the lip. Patients and methods: All patients had been treated at Claudius Regaud Cancer Centre from 1990 to 2008 for squamous cell or basal cell carcinoma. Low-dose-rate brachytherapy was performed with iridium 192 wires according to the Paris system rules. On average, the dose delivered was 65 Gy. Results: 172 consecutive patients were included in our study; 69 had skin carcinoma (squamous cell or basal cell), and 92 had squamous cell mucosal carcinoma. The average follow-up time was 5.4 years. In the skin cancer group, there were five local recurrences and one lymph node recurrence. In the mucosal cancer group, there were ten local recurrences and five lymph node recurrences. The 8-year relapse-free survival for the entire population was 80%. The 8-year relapse-free survival was 85% for skin carcinoma 75% for mucosal carcinoma, with no significant difference between groups. The functional results were satisfactory for 99% of patients, and the cosmetic results were satisfactory for 92%. Maximal toxicity observed was Grade 2. Conclusions: Low-dose-rate brachytherapy can be used to treat lip carcinomas at Stages T1 and T2 as the only treatment with excellent results for local control and relapse-free survival. The benefits of brachytherapy are also cosmetic and functional, with 91% of patients having no side effects.

  9. Photon energy-fluence correction factor in low energy brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, Paula C.G.; Yoriyaz, Hélio [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Vijande, Javier; Giménez-Alventosa, Vicent; Ballester, Facundo, E-mail: pacrisguian@gmail.com [Department of Atomic, Molecular, and Nuclear Physics and Instituto de Física Corpuscular (UV-CSIC), University of Valencia (Spain)

    2017-07-01

    The AAPM TG-43 brachytherapy dosimetry formalism has become a standard for brachytherapy dosimetry worldwide; it implicitly assumes that charged-particle equilibrium (CPE) exists for the determination of absorbed dose to water at different locations. At the time of relating dose to tissue and dose to water, or vice versa, it is usually assumed that the photon fluence in water and in tissues are practically identical, so that the absorbed dose in the two media can be related by their ratio of mass energy-absorption coefficients. The purpose of this work is to study the influence of photon energy-fluence in different media and to evaluate a proposal for energy-fluence correction factors for the conversion between dose-to-tissue (D{sub tis}) and dose-to-water (D{sub w}). State-of-the art Monte Carlo (MC) calculations are used to score photon fluence differential in energy in water and in various human tissues (muscle, adipose and bone) in two different codes, MCNP and PENELOPE, which in all cases include a realistic modeling of the {sup 125}I low-energy brachytherapy seed in order to benchmark the formalism proposed. A correction is introduced that is based on the ratio of the water-to-tissue photon energy-fluences using the large-cavity theory. In this work, an efficient way to correlate absorbed dose to water and absorbed dose to tissue in brachytherapy calculations at clinically relevant distances for low-energy photon emitting seed is proposed. The energy-fluence based corrections given in this work are able to correlate absorbed dose to tissue and absorbed dose to water with an accuracy better than 0.5% in the most critical cases. (author)

  10. Ocular brachytherapy with a holmium-166 irradiator device

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, Arnaldo P. [Centro Federal de Educacao Tecnoloica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar], e-mail: aprata@des.cefetmg.br; Campos, Tarcisio P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares], e-mail: campos@nuclear.ufmg.br

    2009-07-01

    The ocular brachytherapy is a method that allows controlling ocular tumors. However, the irradiation of the ocular area in high doses can bring damages mainly to the surrounding healthy tissue, such as lens, retina and bone tissue of the orbital area in growth phase. Brachytherapy in comparison to teletherapy allows a large reduction of the absorbed doses in the adjacent tissues avoiding deleterious effects. Various types of radionuclides can be applied to ocular brachytherapy. Those radionuclides shall be encapsulated and placed juxtaposed to the sclera, back to the tumor. Herein, a new device was developed to encapsulate the radioactive material. It can easily place back of the eyeball. A computational model of the ocular area was developed in order to simulate the spatial dose distribution promoted by the holmium-166 nuclide distributed inside the irradiator device. The simulations addressed a device placed on the surface of the sclera, rotated 90 deg taken at the normal axis forward to the lens. The simulation was carried on the code Monte Carlo MCNP5. The computational simulation generates the spatial dose distribution in the treated volume. All continuous beta and the discrete gamma and X-ray spectra emitted by the holmium-166 were incorporated on simulations. The results allow comparing the space dose distribution to other types of sources used for the same end. The sclera absorbed dose, the maximum apical tumor dose, as well as on the tumor base were investigated. Indeed, the tumor thickness defines the conditions of irradiation. The holmium-166 dose distribution provides a tool to propose a better and optimized protocol for ocular brachytherapy. (author)

  11. Study of two different radioactive sources for prostate brachytherapy treatment

    International Nuclear Information System (INIS)

    Pereira Neves, Lucio; Perini, Ana Paula; Souza Santos, William de; Caldas, Linda V.E.; Belinato, Walmir

    2015-01-01

    In this study we evaluated two radioactive sources for brachytherapy treatments. Our main goal was to quantify the absorbed doses on organs and tissues of an adult male patient, submitted to a brachytherapy treatment with two radioactive sources. We evaluated a 192 Ir and a 125 I radioactive sources. The 192 Ir radioactive source is a cylinder with 0.09 cm in diameter and 0.415 cm long. The 125 I radioactive source is also a cylinder, with 0.08 cm in diameter and 0.45 cm long. To evaluate the absorbed dose distribution on the prostate, and other organs and tissues of an adult man, a male virtual anthropomorphic phantom MASH, coupled in the radiation transport code MCNPX 2.7.0, was employed.We simulated 75, 90 and 102 radioactive sources of 125 I and one of 192 Ir, inside the prostate, as normally used in these treatments, and each treatment was simulated separately. As this phantom was developed in a supine position, the displacement of the internal organs of the chest, compression of the lungs and reduction of the sagittal diameter were all taken into account. For the 192 Ir, the higher doses values were obtained for the prostate and surrounding organs, as the colon, gonads and bladder. Considering the 125 I sources, with photons with lower energies, the doses to organs that are far from the prostate were lower. All values for the dose rates are in agreement with those recommended for brachytherapy treatments. Besides that, the new seeds evaluated in this work present usefulness as a new tool in prostate brachytherapy treatments, and the methodology employed in this work may be applied for other radiation sources, or treatments. (authors)

  12. Study of two different radioactive sources for prostate brachytherapy treatment

    Energy Technology Data Exchange (ETDEWEB)

    Pereira Neves, Lucio; Perini, Ana Paula [Instituto de Fisica, Universidade Federal de Uberlandia, Caixa Postal 593, 38400-902, Uberlandia, MG (Brazil); Souza Santos, William de; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, IPENCNEN/SP, Av. Prof. Lineu Prestes, 2242, Cidade Universitaria, 05508-000 Sao Paulo, SP (Brazil); Belinato, Walmir [Departamento de Ensino, Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia, Campus Vitoria da Conquista, Zabele, Av. Amazonas 3150, 45030-220 Vitoria da Conquista, BA (Brazil)

    2015-07-01

    In this study we evaluated two radioactive sources for brachytherapy treatments. Our main goal was to quantify the absorbed doses on organs and tissues of an adult male patient, submitted to a brachytherapy treatment with two radioactive sources. We evaluated a {sup 192}Ir and a {sup 125}I radioactive sources. The {sup 192}Ir radioactive source is a cylinder with 0.09 cm in diameter and 0.415 cm long. The {sup 125}I radioactive source is also a cylinder, with 0.08 cm in diameter and 0.45 cm long. To evaluate the absorbed dose distribution on the prostate, and other organs and tissues of an adult man, a male virtual anthropomorphic phantom MASH, coupled in the radiation transport code MCNPX 2.7.0, was employed.We simulated 75, 90 and 102 radioactive sources of {sup 125}I and one of {sup 192}Ir, inside the prostate, as normally used in these treatments, and each treatment was simulated separately. As this phantom was developed in a supine position, the displacement of the internal organs of the chest, compression of the lungs and reduction of the sagittal diameter were all taken into account. For the {sup 192}Ir, the higher doses values were obtained for the prostate and surrounding organs, as the colon, gonads and bladder. Considering the {sup 125}I sources, with photons with lower energies, the doses to organs that are far from the prostate were lower. All values for the dose rates are in agreement with those recommended for brachytherapy treatments. Besides that, the new seeds evaluated in this work present usefulness as a new tool in prostate brachytherapy treatments, and the methodology employed in this work may be applied for other radiation sources, or treatments. (authors)

  13. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    International Nuclear Information System (INIS)

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A.; Wallner, Kent E.

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase ≥25%, 23% of men experienced a decrease ≥25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  14. Fully automated MRI-guided robotics for prostate brachytherapy

    International Nuclear Information System (INIS)

    Stoianovici, D.; Vigaru, B.; Petrisor, D.; Muntener, M.; Patriciu, A.; Song, D.

    2008-01-01

    The uncertainties encountered in the deployment of brachytherapy seeds are related to the commonly used ultrasound imager and the basic instrumentation used for the implant. An alternative solution is under development in which a fully automated robot is used to place the seeds according to the dosimetry plan under direct MRI-guidance. Incorporation of MRI-guidance creates potential for physiological and molecular image-guided therapies. Moreover, MRI-guided brachytherapy is also enabling for re-estimating dosimetry during the procedure, because with the MRI the seeds already implanted can be localised. An MRI compatible robot (MrBot) was developed. The robot is designed for transperineal percutaneous prostate interventions, and customised for fully automated MRI-guided brachytherapy. With different end-effectors, the robot applies to other image-guided interventions of the prostate. The robot is constructed of non-magnetic and dielectric materials and is electricity free using pneumatic actuation and optic sensing. A new motor (PneuStep) was purposely developed to set this robot in motion. The robot fits alongside the patient in closed-bore MRI scanners. It is able to stay fully operational during MR imaging without deteriorating the quality of the scan. In vitro, cadaver, and animal tests showed millimetre needle targeting accuracy, and very precise seed placement. The robot tested without any interference up to 7T. The robot is the first fully automated robot to function in MRI scanners. Its first application is MRI-guided seed brachytherapy. It is capable of automated, highly accurate needle placement. Extensive testing is in progress prior to clinical trials. Preliminary results show that the robot may become a useful image-guided intervention instrument. (author)

  15. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Taira, Al V. [Western Radiation Oncology, Mountain View, CA (United States); Merrick, Gregory S., E-mail: gmerrick@urologicresearchinstitute.org [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, WV (United States); Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A. [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, WV (United States); Wallner, Kent E. [Puget Sound Healthcare Corporation Group Health Cooperative, University of Washington, Seattle, WA (United States)

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase {>=}25%, 23% of men experienced a decrease {>=}25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  16. Manual on brachytherapy. Incorporating: Applications guide, procedures guide, basics guide

    International Nuclear Information System (INIS)

    1996-01-01

    This publication is part of practical radiation safety manual series for different fields of application aimed primarily at persons handling radiation sources on a daily routine basis, which could at same time be used by the competent authorities, supporting their efforts in the radiation protection training of workers or medical assistance personnel or helping on-site management to set up local radiation protection rules. It is dedicated to brachytherapy: its application and procedures guides

  17. HDR brachytherapy for superficial non-melanoma skin cancers

    International Nuclear Information System (INIS)

    Gauden, Ruth; Pracy, Martin; Avery, Anne-Marie; Hodgetts, Ian; Gauden, Stan

    2013-01-01

    Our initial experience using recommended high dose per fraction skin brachytherapy (BT) treatment schedules, resulted in poor cosmesis. This study aimed to assess in a prospective group of patients the use of Leipzig surface applicators for High Dose Rate (HDR) brachytherapy, for the treatment of small non-melanoma skin cancers (NMSC) using a protracted treatment schedule. Treatment was delivered by HDR brachytherapy with Leipzig applicators. 36Gy, prescribed to between 3 to 4mm, was given in daily 3Gy fractions. Acute skin toxicity was evaluated weekly during irradiation using the Radiation Therapy Oncology Group criteria. Local response, late skin effects and cosmetic results were monitored at periodic intervals after treatment completion. From March 2002, 200 patients with 236 lesions were treated. Median follow-up was 66 months (range 25–121 months). A total of 162 lesions were macroscopic, while in 74 cases, BT was given after resection because of positive microscopic margins. There were 121 lesions that were basal cell carcinomas, and 115 were squamous cell carcinomas. Lesions were located on the head and neck (198), the extremities (26) and trunk (12). Local control was 232/236 (98%). Four patients required further surgery to treat recurrence. Grade 1 acute skin toxicity was detected in 168 treated lesions (71%) and grade 2 in 81 (34%). Cosmesis was good or excellent in 208 cases (88%). Late skin hypopigmentation changes were observed in 13 cases (5.5%). Delivering 36Gy over 2 weeks to superficial NMSC using HDR brachytherapy is well tolerated and provides a high local control rate without significant toxicity.

  18. Primary calibration of coiled 103Pd brachytherapy sources

    International Nuclear Information System (INIS)

    Paxton, Adam B.; Culberson, Wesley S.; DeWerd, Larry A.; Micka, John A.

    2008-01-01

    Coiled 103 Pd brachytherapy sources have been developed by RadioMed Corporation for use as low-dose-rate (LDR) interstitial implants. The coiled sources are provided in integer lengths from 1 to 6 cm and address many common issues seen with traditional LDR brachytherapy sources. The current standard for determining the air-kerma strength (S K ) of low-energy LDR brachytherapy sources is the National Institute of Standards and Technology's Wide-Angle Free-Air Chamber (NIST WAFAC). Due to geometric limitations, however, the NIST WAFAC is unable to determine the S K of sources longer than 1 cm. This project utilized the University of Wisconsin's Variable-Aperture Free-Air Chamber (UW VAFAC) to determine the S K of the longer coiled sources. The UW VAFAC has shown agreement in S K values of 1 cm length coils to within 1% of those determined with the NIST WAFAC, but the UW VAFAC does not share the same geometric limitations as the NIST WAFAC. A new source holder was constructed to hold the coiled sources in place during measurements with the UW VAFAC. Correction factors for the increased length of the sources have been determined and applied to the measurements. Using the new source holder and corrections, the S K of 3 and 6 cm coiled sources has been determined. Corrected UW VAFAC data and ionization current measurements from well chambers have been used to determine calibration coefficients for use in the measurement of 3 and 6 cm coiled sources in well chambers. Thus, the UW VAFAC has provided the first transferable, primary measurement of low-energy LDR brachytherapy sources with lengths greater than 1 cm

  19. Ocular brachytherapy with a holmium-166 irradiator device

    International Nuclear Information System (INIS)

    Mourao, Arnaldo P.; Campos, Tarcisio P.R.

    2009-01-01

    The ocular brachytherapy is a method that allows controlling ocular tumors. However, the irradiation of the ocular area in high doses can bring damages mainly to the surrounding healthy tissue, such as lens, retina and bone tissue of the orbital area in growth phase. Brachytherapy in comparison to teletherapy allows a large reduction of the absorbed doses in the adjacent tissues avoiding deleterious effects. Various types of radionuclides can be applied to ocular brachytherapy. Those radionuclides shall be encapsulated and placed juxtaposed to the sclera, back to the tumor. Herein, a new device was developed to encapsulate the radioactive material. It can easily place back of the eyeball. A computational model of the ocular area was developed in order to simulate the spatial dose distribution promoted by the holmium-166 nuclide distributed inside the irradiator device. The simulations addressed a device placed on the surface of the sclera, rotated 90 deg taken at the normal axis forward to the lens. The simulation was carried on the code Monte Carlo MCNP5. The computational simulation generates the spatial dose distribution in the treated volume. All continuous beta and the discrete gamma and X-ray spectra emitted by the holmium-166 were incorporated on simulations. The results allow comparing the space dose distribution to other types of sources used for the same end. The sclera absorbed dose, the maximum apical tumor dose, as well as on the tumor base were investigated. Indeed, the tumor thickness defines the conditions of irradiation. The holmium-166 dose distribution provides a tool to propose a better and optimized protocol for ocular brachytherapy. (author)

  20. Proposals for common definitions of reference points in gynecological brachytherapy

    International Nuclear Information System (INIS)

    Chassagne, D.; Horiot, J.C.

    1977-01-01

    In May 1975 the report of European Curietherapy Group recommended in gynecological Dosimetry by computer. Use of reference points = lymphatic trapezoid figure with 6 points, Pelvic wall, all points are refering to bony structures. Use of critical organ reference points = maximum rectum dose, bladder dose mean rectal dose. Use of 6,000 rads reference isodose described by height, width, and thickness dimensions. These proposals are the basis of a common language in gynecological brachytherapy [fr

  1. Intracavitary mould brachytherapy in malignant tumors of the maxilla

    International Nuclear Information System (INIS)

    Rosenblatt, Edward; Blumenfeld, Israel; Cederbaum, Martin; Kuten, Abraham

    1996-01-01

    Purpose: To integrate brachytherapy in the combined modality management of malignant tumors of the maxilla, as a means of increasing the radiotherapy dose to the tumor bed while avoiding high doses to the orbital contents. Materials and methods: Following a partial or total maxillectomy, a duplication of the interim surgical obturator was created using a wash of vinyl polysiloxane. This mould was used as a carrier for afterloading nylon catheters through which 192-Iridium seed-ribbons were inserted. Following brachytherapy, selected patients also received external beam irradiation. Results and discussion: After a median follow-up of 36 months, 9 out of 11 patients are alive and disease-free; 1 developed a local recurrence and another relapsed at another site in the oral cavity. Transient grade 1 - 2 mucositis at the implant site was observed in all patients. The review of computer isodose distributions showed that the average dose received by the homolateral eyeball was 10% (range 9,2 - 10.0) of the prescribed surface dose to the surgical cavity. Conclusions: Brachytherapy can be integrated in the management of patients with malignant tumors of the maxilla in the form of a custom-made intracavitary mould carrying 192-Iridium sources. We found this technique particularly useful in cases with close or positive surgical margins

  2. Visual acuity after Ruthenium106 brachytherapy of choroidal melanomas

    International Nuclear Information System (INIS)

    Damato, Bertil; Patel, Imran M.; Campbell, Ian R.; Mayles, Helen M.; Errington, R. Douglas

    2005-01-01

    Purpose: To report on conservation of visual acuity after Ruthenium 106 (Ru-106) brachytherapy of choroidal melanoma. Methods and materials: This study was a noncomparative interventional case series of 458 patients with choroidal melanoma treated at a single center between January 1993 and December 2001. The intervention consisted of Ru-106 brachytherapy delivering minimum scleral and apex doses of 300 Gy and 80 Gy, respectively, using a 15-mm or 20-mm plaque. For discrete, posterior tumors, the plaque was positioned eccentrically with its posterior edge aligned with the posterior tumor margin. To ensure correct plaque positioning, any overlying extraocular muscles were dis-inserted, and the locations of both tumor and plaque edges were confirmed by transillumination and indentation. The main outcome measures were conservation of vision of 20/40 or better, 20/200 or better, and Counting Fingers or better, according to baseline variables. Results: The actuarial rate of conservation of 20/40 or better was 55% at 9 years, loss of such vision correlating with posterior tumor extension (p 106 brachytherapy of posterior choroidal melanoma achieves good conservation of vision if the tumor does not extend close to the optic nerve or fovea

  3. Invited review, recent developments in brachytherapy source dosimetry

    International Nuclear Information System (INIS)

    Meigooni, A.S.

    2004-01-01

    Application of radioactive isotopes is the treatment of choice around the globe for many cancer sites. In this technique, the accuracy of the radiation delivery is highly dependent on the accuracy of radiation dosimetry around individual brachytherapy sources. Moreover, in order to have compatible clinical results, an identical method of source dosimetry must be employed across the world. This problem has been recently addressed by task group 43 from the American Association of Medical Physics with a protocol for dosimetric characterization of brachytherapy sources. This new protocol has been further updated using published data from international sources, by a new Task Group from the American Association of Medical Physics. This has resulted in an updated protocol known as TG43U1 that has been published in March 2004 issue of Medical Physics. The goal of this presentation is to review the original Task Group 43 protocol and associated algorithms for brachytherapy source dosimetry. In addition, the shortcomings of the original protocol that has been resolved in the updated recommendation will be highlighted. I am sure that this is not the end of the line and more work is needed to complete this task. I invite the scientists to join this task and complete the project, with the hope of much better clinical results for cancer patients

  4. Radiation safety program in a high dose rate brachytherapy facility

    International Nuclear Information System (INIS)

    Rodriguez, L.V.; Hermoso, T.M.; Solis, R.C.

    2001-01-01

    The use of remote afterloading equipment has been developed to improve radiation safety in the delivery of treatment in brachytherapy. Several accidents, however, have been reported involving high dose-rate brachytherapy system. These events, together with the desire to address the concerns of radiation workers, and the anticipated adoption of the International Basic Safety Standards for Protection Against Ionizing Radiation (IAEA, 1996), led to the development of the radiation safety program at the Department of Radiotherapy, Jose R. Reyes Memorial Medical Center and at the Division of Radiation Oncology, St. Luke's Medical Center. The radiation safety program covers five major aspects: quality control/quality assurance, radiation monitoring, preventive maintenance, administrative measures and quality audit. Measures for evaluation of effectiveness of the program include decreased unnecessary exposures of patients and staff, improved accuracy in treatment delivery and increased department efficiency due to the development of staff vigilance and decreased anxiety. The success in the implementation required the participation and cooperation of all the personnel involved in the procedures and strong management support. This paper will discuss the radiation safety program for a high dose rate brachytherapy facility developed at these two institutes which may serve as a guideline for other hospitals intending to install a similar facility. (author)

  5. Survey of brachytherapy practice in France in 1995. Definitive results

    International Nuclear Information System (INIS)

    Peiffert, D.; Simon, J.M.; Baillet, F.

    1998-01-01

    A survey questionnaire was sent to the 189 French departments of radiation Oncology and 166 responded (88%). Ninety-nine departments declared treating patients by brachytherapy and 358 shielded rooms were available. In Low Dose Rate (LDR) 81 departments used Cesium sources (159 after-loaders, 1,060 sources); Iridium wires were used by 84 departments (673 meters used). Only six departments used other elements. Twenty-six departments were equipped with high dose rate after loaders (HDR) all of them also using LDR techniques for most of the patients. A total of 9,160 patients were treated: 7,868 with LDR and 1,292 with HDR. The common sites treated by LDR were utero-vagina (4,300), breast (1,415), head and neck (1,409), skin (610), anorectal (220) and urologic (70). HDR was used for vaginal cuff (628), bronchi (371), oesophagus (232). PDR just started (33 patients) for a feasibility trial. The rate of patients treated by brachytherapy is around 6-8% of the irradiated patients, but the indications vary is each department. The diffusion of the techniques, and new indications should increase the number of patients being treated by brachytherapy. (authors)

  6. Radiobiological considerations in gynaecological HDR and LDR brachytherapy

    International Nuclear Information System (INIS)

    Bauer, M.; Schulz-Wendtland, R.

    1989-01-01

    In brachytherapy the advantages of high dose rate over low dose rate afterloading therapy were obvious. Out-patient treatment becomes possible, the position of the sources is reproducible and can be observed during the treatment and the patients have to be immobilised for only a short time, giving less psychological stress and a decreased risk of thrombosis and embolism. When changing from LDR to HDR afterloading therapy we are not yet able to evaluate its biological impact. Radiobiological considerations and our experimental data, however, give us the following clinical consequences by using HDR brachytherapy: There is a need for about 15 fractions or more and each increase in dose rate requires higher fractioning. Due to the steep dose rate decline and the inhomogeneous dose distribution, multiple equivalence factors are necessary when fractioning is not sufficiently high. Correction factors to reduce the dose close to the source are low, with increasing distance from the source they increase. If HDR radiation therapy is used, the percutaneous dose in the pelvic wall region should be reduced. The reduction of the dose in HDR brachytherapy is a compromise to limit the side effects caused by the radiation. The drawback is a small therapeutic range and reduced therapeutic effectivity at the tumour. (orig.) [de

  7. Brachytherapy for treatment of cervix cancer in Madagascar

    International Nuclear Information System (INIS)

    Pignon, T.; Ratovonarivo, H.; Rafaramino, F.; Ruggieri, S.

    1993-01-01

    From March 1986 to June 1988, 60 patients with carcinoma of the uterine cervix were treated by radiotherapy alone or combined radiotherapy and surgery at the only radiotherapy-oncology department of Madagascar in Antananarivo. There were 20 stage IB, 28 stage II, 5 stage III and 7 cases where initial stage before surgery was unknown. After a limited pre-therapeutic investigation, treatment for stage IB consisted of utero-vaginal brachytherapy followed by a colpo-hysterectomy and external iliac lymphadenectomy. Others received combined external radiotherapy and brachytherapy according to the Fletcher guidelines, although 30 patients also received surgery. An obsolete and inefficient cobalt unit with lack of computerized dosimetry made the management of therapeutic schemas difficult. Nineteen patients (31.6%) were not available for follow-up immediately after the end of the treatment and one patient died from intestinal occlusion during brachytherapy. The overall rate of severe complications was 4.8%. There were 12 recurrences which occurred in stage II or in patients with unknown initial staging. At the time of analysis, 25 patients were alive: 15 stage I and 10 stage II. In this country, cervical carcinomas are the most frequent tumors: only the rehabilitation of radiotherapy facilities will allow results to be improved

  8. Patterns of care for brachytherapy in Europe: Updated results

    International Nuclear Information System (INIS)

    Guedea, Ferran; Venselaar, Jack; Hoskin, Peter; Hellebust, Taran Paulsen; Peiffert, Didier; Londres, Bradley; Ventura, Montse; Mazeron, Jean-Jacques; Van Limbergen, Erik; Poetter, Richard; Kovacs, Gyorgy

    2010-01-01

    Objective: This descriptive survey evaluated brachytherapy (BT) practices and resources in the European area. This was a follow-up study to the original patterns of care for brachytherapy in Europe (PCBE). Materials and methods: A total of 1121 radiotherapy (RT) centres from 41 countries were asked to complete an online questionnaire on BT practices and resources. Countries with fewer than 50% of centres responding were excluded. Participating countries were divided into three groups based on gross domestic product (GDP); group I contained the countries with the highest GDP. Results: The response rate was 56% (633/1121 centres) with 30/41 countries (73%) meeting the inclusion criteria. Sixty percent of reporting centres provided brachytherapy. Responding centres treated an average of 138 (±10, 1 SD) patients with BT; in group I, the mean was 110/centre, an increase of 18% from 2002. CT-dosimetry increased to 61% of centres vs. 33% in 2002. HDR (high-dose rate) BT was the most commonly reported technique (65% of centres). Most BT interventions were for gynaecological tumors (59% of all cases), followed by prostate (17%), breast (9%), lung/bronchus (3%), and esophagus tumors(2%). Conclusion: Gynaecological BT remains the most common application, although both prostate and breast BT have increased. CT-based dosimetry has become increasingly common since 2002. The use of HDR and PDR (pulsed-dose rate) techniques has increased markedly, while both LDR and MDR (medium-dose rate) have declined.

  9. Implication for QOL after I-125 brachytherapy for prostate cancer

    International Nuclear Information System (INIS)

    Teishima, Jun; Yasumoto, Hiroaki; Inoue, Syogo; Masumoto, Hiroshi; Hasegawa, Yasuhisa; Matsubara, Akio

    2009-01-01

    The aim of this study is to evaluate the quality of life (QOL) of patients following prostate brachytherapy. Between July 2004 and May 2008, 139 patients underwent I-125 permanent brachytherapy. Among those patients, 69 who were followed up for more than one year using the Expanded Prostate Index Composite (EPIC), Japanese version v1 TM , were enrolled in this study. Urinary summary scores became worse temporarily at 1 month after the end of treatment, but then recovered gradually to the level before treatment. Sexual summary scores before treatment were 42.2±16.3. They became worse temporarily at 1 month after treatment but then recovered gradually in patients whose sexual summary scores were more than 40. Urinary morbidity scores after prostate brachytherapy were not so severe and recovered within a short period. Further long-term observation is thought to be required in the future. Sexual function scores of patients before treatment in the present study were lower compared with those recorded in previous studies. (author)

  10. Audits in high dose rate brachytherapy in Brazil

    International Nuclear Information System (INIS)

    Marechal, M.H.; Rosa, L.A.; Velasco, A.; Paiva, E. de; Goncalves, M.; Castelo, L.C.

    2002-01-01

    The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country. The main objective of this paper is to report the results of an implementation of the audit program in dosimetry of high dose rate brachytherapy sources used by the radiation therapy centers in Brazil. In Brazil, among 169 radiotherapy centers, 35 have HDR brachytherapy systems. This program started in August 2001 and until now eight radiotherapy services were audited. The audit program consists of the visit in loco to each center and the evaluation of the intensity of the source with a well type chamber specially design for HDR 192 Ir sources. The measurements was carried out with a HDR1000PLUS Brachytherapy Well Type Chamber and a MAX 4000 Electrometer, both manufactured by Standard Imaging Inc. The chamber was calibrated in air kerma strength by the Accredited Dosimetry Calibration Laboratory, Department of Medical Physics, University of Wisconsin in the USA. The same chamber was calibrated in Brazil using a 192 lr high dose rate source whose intensity was determined by 60 Co gamma rays and 250 kV x rays interpolation methodology. The Nk of 60 Co and 250 kV x rays were provided by the Brazilian National Standard Laboratory for Ionizing Radiation (LMNRI)

  11. Does immediate postoperative brachytherapy allow to broaden the indications of conservative treatment in breast cancer?

    International Nuclear Information System (INIS)

    Floiras, J.L.

    1998-01-01

    A 1997 study of long-term outcomes in 109 patients with unilateral stage I or II breast cancer treated by brachytherapy between 1983 and 1985 found significantly lower recurrence rates than in a conservatively-treated group of patients managed at the same institution. The benefits of brachytherapy, of a booster dose after after surgery, and of adjuvant medical therapy are emphasized. (author)

  12. A compilation of current regulations, standards and guidelines in remote afterloading brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tortorelli, J.P.; Simion, G.P.; Kozlowski, S.D. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-10-01

    Over a dozen government and professional organizations in the United States and Europe have issued regulations and guidance concerning quality management in the practice of remote afterloading brachytherapy. Information from the publications of these organizations was collected and collated for this report. This report provides the brachytherapy licensee access to a broad field of quality management information in a single, topically organized document.

  13. A compilation of current regulations, standards and guidelines in remote afterloading brachytherapy

    International Nuclear Information System (INIS)

    Tortorelli, J.P.; Simion, G.P.; Kozlowski, S.D.

    1994-10-01

    Over a dozen government and professional organizations in the United States and Europe have issued regulations and guidance concerning quality management in the practice of remote afterloading brachytherapy. Information from the publications of these organizations was collected and collated for this report. This report provides the brachytherapy licensee access to a broad field of quality management information in a single, topically organized document

  14. Brachytherapy boost for breast cancer: what do we know? where do we go?

    International Nuclear Information System (INIS)

    Hannoun-Levi, J.M.; Marsiglia, H.

    2004-01-01

    Since many years, Brachytherapy (BT) appears to play an important role in the treatment of many solid tumors. For breast cancer, BT is usually used as boost after postoperative external beam radiation therapy. In certain circumstances. BT can be used as sole radiation technique focalized on the tumor bed or more rarely, as second conservative treatment in case of local recurrence for woman refusing salvage mastectomy. Boost BT is most often applied via an interstitial technique while the dose rate can vary from low to high close rate through pulse dose rate. All of those boost techniques were published and some of them compared the results obtained with BT and external beam electron therapy. The analysis of the published phase II and III trials was not able to show significant differences between the two boost techniques in term of local control as well as late skin side effects. However, we noted that the patients who received BT boost presented a higher risk of local recurrence compare to those treated with electron therapy, due to age, margin status or presence of extensive intraductal component. Only a phase III trial randomizing BT boost vs electron therapy boost could show a possible improvement of local control rate in the BT arm; however, this trial should enroll patients with a real high risk of local recurrence in order to take benefit from the dosimetric advantages of BT. (author)

  15. American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

    Science.gov (United States)

    Spratt, Daniel E; Soni, Payal D; McLaughlin, Patrick W; Merrick, Gregory S; Stock, Richard G; Blasko, John C; Zelefsky, Michael J

    To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All

  16. Contemporary Toxicity Profile of Breast Brachytherapy Versus External Beam Radiation After Lumpectomy for Breast Cancer

    International Nuclear Information System (INIS)

    Huo, Jinhai; Giordano, Sharon H.; Smith, Benjamin D.; Shaitelman, Simona F.; Smith, Grace L.

    2016-01-01

    Purpose: We compared toxicities after brachytherapy versus external beam radiation therapy (EBRT) in contemporary breast cancer patients. Methods and Materials: Using MarketScan healthcare claims, we identified 64,112 women treated from 2003 to 2012 with lumpectomy followed by radiation (brachytherapy vs EBRT). Brachytherapy was further classified by multichannel versus single-channel applicator approach. We identified the risks and predictors of 1-year infectious and noninfectious postoperative adverse events using logistic regression and temporal trends using Cochran-Armitage tests. We estimated the 5-year Kaplan-Meier cumulative incidence of radiation-associated adverse events. Results: A total of 4522 (7.1%) patients received brachytherapy (50.2% multichannel vs 48.7% single-channel applicator). The overall risk of infectious adverse events was higher after brachytherapy than after EBRT (odds ratio [OR] = 1.21; 95% confidence interval [CI] 1.09-1.34, P<.001). However, over time, the frequency of infectious adverse events after brachytherapy decreased, from 17.3% in 2003 to 11.6% in 2012, and was stable after EBRT at 9.7%. Beyond 2007, there were no longer excess infections with brachytherapy (P=.97). The overall risk of noninfectious adverse events was higher after brachytherapy than after EBRT (OR=2.27; 95% CI 2.09-2.47, P<.0001). Over time, the frequency of noninfectious adverse events detected increased: after multichannel brachytherapy, from 9.1% in 2004 to 18.9% in 2012 (Ptrend = .64); single-channel brachytherapy, from 12.8% to 29.8% (Ptrend<.001); and EBRT, from 6.1% to 10.3% (Ptrend<.0001). The risk was significantly higher with single-channel than with multichannel brachytherapy (hazard ratio = 1.32; 95% CI 1.03-1.69, P=.03). Of noninfectious adverse events, 70.9% were seroma. Seroma significantly increased breast pain risk (P<.0001). Patients with underlying diabetes, cardiovascular disease, and treatment with chemotherapy had increased

  17. Contemporary Toxicity Profile of Breast Brachytherapy Versus External Beam Radiation After Lumpectomy for Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Huo, Jinhai [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Shaitelman, Simona F. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Grace L., E-mail: glsmith@mdanderson.org [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2016-03-15

    Purpose: We compared toxicities after brachytherapy versus external beam radiation therapy (EBRT) in contemporary breast cancer patients. Methods and Materials: Using MarketScan healthcare claims, we identified 64,112 women treated from 2003 to 2012 with lumpectomy followed by radiation (brachytherapy vs EBRT). Brachytherapy was further classified by multichannel versus single-channel applicator approach. We identified the risks and predictors of 1-year infectious and noninfectious postoperative adverse events using logistic regression and temporal trends using Cochran-Armitage tests. We estimated the 5-year Kaplan-Meier cumulative incidence of radiation-associated adverse events. Results: A total of 4522 (7.1%) patients received brachytherapy (50.2% multichannel vs 48.7% single-channel applicator). The overall risk of infectious adverse events was higher after brachytherapy than after EBRT (odds ratio [OR] = 1.21; 95% confidence interval [CI] 1.09-1.34, P<.001). However, over time, the frequency of infectious adverse events after brachytherapy decreased, from 17.3% in 2003 to 11.6% in 2012, and was stable after EBRT at 9.7%. Beyond 2007, there were no longer excess infections with brachytherapy (P=.97). The overall risk of noninfectious adverse events was higher after brachytherapy than after EBRT (OR=2.27; 95% CI 2.09-2.47, P<.0001). Over time, the frequency of noninfectious adverse events detected increased: after multichannel brachytherapy, from 9.1% in 2004 to 18.9% in 2012 (Ptrend = .64); single-channel brachytherapy, from 12.8% to 29.8% (Ptrend<.001); and EBRT, from 6.1% to 10.3% (Ptrend<.0001). The risk was significantly higher with single-channel than with multichannel brachytherapy (hazard ratio = 1.32; 95% CI 1.03-1.69, P=.03). Of noninfectious adverse events, 70.9% were seroma. Seroma significantly increased breast pain risk (P<.0001). Patients with underlying diabetes, cardiovascular disease, and treatment with chemotherapy had increased

  18. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    Science.gov (United States)

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-07

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  19. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Al-Qaisieh, Bashar [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Mason, Josh, E-mail: joshua.mason@nhs.net [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Bownes, Peter; Henry, Ann [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Dickinson, Louise [Division of Surgery and Interventional Science, University College London, London (United Kingdom); Department of Radiology, Northwick Park Hospital, London North West NHS Trust, London (United Kingdom); Ahmed, Hashim U. [Division of Surgery and Interventional Science, University College London, London (United Kingdom); University College London Hospital, London (United Kingdom); Emberton, Mark [University College London Hospital, London (United Kingdom); Langley, Stephen [St Luke' s Cancer Centre, Guildford (United Kingdom)

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focal (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a notable

  20. Relocation of a nucletron microselectron-HDR brachytherapy system

    Energy Technology Data Exchange (ETDEWEB)

    Bartrum, T; Tran, T; Freeman, N; Morales, J [St Vincents Hospital, Darlinghurst, NSW (Australia)

    2004-12-15

    Full text: For a period of four weeks, our clinical Nucletron microSelectron high dose rate (HDR) brachytherapy system was pulled out of clinical use and relocated to a new building. During this period decommission tests, de-wiring of the treatment unit and its associated safety system (such as radiation detector, emergency off circuits and door interlocks), transportation of all equipment, re-wiring of this equipment in the new location and recommission tests were carried out. The decommission and recommission test program was designed upon consultation with the manufacturer's (Nucletron) acceptance test procedures and work carried out by others. The ACPSEM tolerances for remote afterloaders was used as a guideline. In addition to mandatory dosimetry, positional, workstation database and safety tests, two Australian Standard compliance tests were carried out. The compliance tests involved one for remote afterloaders and another for treatment room design. This testing program was designed and implemented with the aim of ensuring ongoing safe delivery of brachytherapy doses to the patient. The testing program consisted of two parts. The first involved a series of decommissioning tests that consisted of dosimetry tests such as source and check cable positional accuracy and source calibration tests. In addition to these tests an inventory of standard plans, patient records and system configuration information was catalogued. The second part involved a series of recommission tests and involved carrying out dosimetry tests on the brachytherapy system (positional accuracy and calibration tests), simulating common treatment scenarios (prostate, cervical, vaginal and bile duct) and checking standard plans; patient records and system configuration had remained unchanged. During this period, other tests were carried out. These included Nucletron acceptance and preventative maintenance tests, Australian Standards compliance testing and integrity of network transfer of

  1. Relocation of a nucletron microselectron-HDR brachytherapy system

    International Nuclear Information System (INIS)

    Bartrum, T.; Tran, T.; Freeman, N.; Morales, J.

    2004-01-01

    Full text: For a period of four weeks, our clinical Nucletron microSelectron high dose rate (HDR) brachytherapy system was pulled out of clinical use and relocated to a new building. During this period decommission tests, de-wiring of the treatment unit and its associated safety system (such as radiation detector, emergency off circuits and door interlocks), transportation of all equipment, re-wiring of this equipment in the new location and recommission tests were carried out. The decommission and recommission test program was designed upon consultation with the manufacturer's (Nucletron) acceptance test procedures and work carried out by others. The ACPSEM tolerances for remote afterloaders was used as a guideline. In addition to mandatory dosimetry, positional, workstation database and safety tests, two Australian Standard compliance tests were carried out. The compliance tests involved one for remote afterloaders and another for treatment room design. This testing program was designed and implemented with the aim of ensuring ongoing safe delivery of brachytherapy doses to the patient. The testing program consisted of two parts. The first involved a series of decommissioning tests that consisted of dosimetry tests such as source and check cable positional accuracy and source calibration tests. In addition to these tests an inventory of standard plans, patient records and system configuration information was catalogued. The second part involved a series of recommission tests and involved carrying out dosimetry tests on the brachytherapy system (positional accuracy and calibration tests), simulating common treatment scenarios (prostate, cervical, vaginal and bile duct) and checking standard plans; patient records and system configuration had remained unchanged. During this period, other tests were carried out. These included Nucletron acceptance and preventative maintenance tests, Australian Standards compliance testing and integrity of network transfer of

  2. Determining profile of dose distribution for PD-103 brachytherapy source

    International Nuclear Information System (INIS)

    Berkay, Camgoz; Mehmet, N. Kumru; Gultekin, Yegin

    2006-01-01

    Full text: Brachytherapy is a particular radiotherapy for cancer treatments. By destructing cancerous cells using radiation, the treatment proceeded. When alive tissues are subject it is hazardous to study experimental. For brachytherapy sources generally are studied as theoretical using computer simulation. General concept of the treatment is to locate the radioactive source into cancerous area of related tissue. In computer studies Monte Carlo mathematical method that is in principle based on random number generations, is used. Palladium radioisotope is LDR (Low radiation Dose Rate) source. Main radioactive material was coated with titanium cylinder with 3mm length, 0.25 mm radius. There are two parts of Pd-103 in the titanium cylinder. It is impossible to investigate differential effects come from two part as experimental. Because the source dimensions are small compared with measurement distances. So there is only simulation method. In dosimetric studies it is aimed to determine absorbed dose distribution in tissue as radial and angular. In nuclear physics it is obligation to use computer based methods for researchers. Radiation studies have hazards for scientist and people interacted with radiation. When hazard exceed over recommended limits or physical conditions are not suitable (long work time, non economical experiments, inadequate sensitivity of materials etc.) it is unavoidable to simulate works and experiments before practices of scientific methods in life. In medical area, usage of radiation is required computational work for cancer treatments. Some computational studies are routine in clinics and other studies have scientific development purposes. In brachytherapy studies there are significant differences between experimental measurements and theoretical (computer based) output data. Errors of data taken from experimental studies are larger than simulation values errors. In design of a new brachytherapy source it is important to consider detailed

  3. Third-party brachytherapy source calibrations and physicist responsibilities: Report of the AAPM Low Energy Brachytherapy Source Calibration Working Group

    International Nuclear Information System (INIS)

    Butler, Wayne M.; Bice, William S. Jr.; DeWerd, Larry A.; Hevezi, James M.; Huq, M. Saiful; Ibbott, Geoffrey S.; Palta, Jatinder R.; Rivard, Mark J.; Seuntjens, Jan P.; Thomadsen, Bruce R.

    2008-01-01

    The AAPM Low Energy Brachytherapy Source Calibration Working Group was formed to investigate and recommend quality control and quality assurance procedures for brachytherapy sources prior to clinical use. Compiling and clarifying recommendations established by previous AAPM Task Groups 40, 56, and 64 were among the working group's charges, which also included the role of third-party handlers to perform loading and assay of sources. This document presents the findings of the working group on the responsibilities of the institutional medical physicist and a clarification of the existing AAPM recommendations in the assay of brachytherapy sources. Responsibility for the performance and attestation of source assays rests with the institutional medical physicist, who must use calibration equipment appropriate for each source type used at the institution. Such equipment and calibration procedures shall ensure secondary traceability to a national standard. For each multi-source implant, 10% of the sources or ten sources, whichever is greater, are to be assayed. Procedures for presterilized source packaging are outlined. The mean source strength of the assayed sources must agree with the manufacturer's stated strength to within 3%, or action must be taken to resolve the difference. Third party assays do not absolve the institutional physicist from the responsibility to perform the institutional measurement and attest to the strength of the implanted sources. The AAPM leaves it to the discretion of the institutional medical physicist whether the manufacturer's or institutional physicist's measured value should be used in performing dosimetry calculations

  4. WE-F-BRD-01: HDR Brachytherapy II: Integrating Imaging with HDR

    Energy Technology Data Exchange (ETDEWEB)

    Craciunescu, O [Duke University Medical Center, Durham, NC (United States); Todor, D [Virginia Commonwealth University, Richmond, VA (United States); Leeuw, A de

    2014-06-15

    In recent years, with the advent of high/pulsed dose rate afterloading technology, advanced treatment planning systems, CT/MRI compatible applicators, and advanced imaging platforms, image-guided adaptive brachytherapy treatments (IGABT) have started to play an ever increasing role in modern radiation therapy. The most accurate way to approach IGABT treatment is to provide the infrastructure that combines in a single setting an appropriate imaging device, a treatment planning system, and a treatment unit. The Brachytherapy Suite is not a new concept, yet the modern suites are incorporating state-of-the-art imaging (MRI, CBCT equipped simulators, CT, and /or US) that require correct integration with each other and with the treatment planning and delivery systems. Arguably, an MRI-equipped Brachytherapy Suite is the ideal setup for real-time adaptive brachytherapy treatments. The main impediment to MRI-IGABT adoption is access to MRI scanners. Very few radiation oncology departments currently house MRI scanners, and even fewer in a dedicated Brachytherapy Suite. CBCT equipped simulators are increasingly offered by manufacturers as part of a Brachytherapy Suite installation. If optimized, images acquired can be used for treatment planning, or can be registered with other imaging modalities. This infrastructure is relevant for all forms of brachytherapy, especially those utilizing multi-fractionated courses of treatment such as prostate and cervix. Moreover, for prostate brachytherapy, US imaging systems can be part of the suite to allow for real-time HDR/LDR treatments. Learning Objectives: Understand the adaptive workflow of MR-based IGBT for cervical cancer. Familiarize with commissioning aspects of a CBCT equipped simulator with emphasis on brachytherapy applications Learn about the current status and future developments in US-based prostate brachytherapy.

  5. WE-F-BRD-01: HDR Brachytherapy II: Integrating Imaging with HDR

    International Nuclear Information System (INIS)

    Craciunescu, O; Todor, D; Leeuw, A de

    2014-01-01

    In recent years, with the advent of high/pulsed dose rate afterloading technology, advanced treatment planning systems, CT/MRI compatible applicators, and advanced imaging platforms, image-guided adaptive brachytherapy treatments (IGABT) have started to play an ever increasing role in modern radiation therapy. The most accurate way to approach IGABT treatment is to provide the infrastructure that combines in a single setting an appropriate imaging device, a treatment planning system, and a treatment unit. The Brachytherapy Suite is not a new concept, yet the modern suites are incorporating state-of-the-art imaging (MRI, CBCT equipped simulators, CT, and /or US) that require correct integration with each other and with the treatment planning and delivery systems. Arguably, an MRI-equipped Brachytherapy Suite is the ideal setup for real-time adaptive brachytherapy treatments. The main impediment to MRI-IGABT adoption is access to MRI scanners. Very few radiation oncology departments currently house MRI scanners, and even fewer in a dedicated Brachytherapy Suite. CBCT equipped simulators are increasingly offered by manufacturers as part of a Brachytherapy Suite installation. If optimized, images acquired can be used for treatment planning, or can be registered with other imaging modalities. This infrastructure is relevant for all forms of brachytherapy, especially those utilizing multi-fractionated courses of treatment such as prostate and cervix. Moreover, for prostate brachytherapy, US imaging systems can be part of the suite to allow for real-time HDR/LDR treatments. Learning Objectives: Understand the adaptive workflow of MR-based IGBT for cervical cancer. Familiarize with commissioning aspects of a CBCT equipped simulator with emphasis on brachytherapy applications Learn about the current status and future developments in US-based prostate brachytherapy

  6. Interstitial high-dose-rate brachytherapy in the treatment of base of tongue carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Takacsi-Nagy, Z.; Polgar, C.; Somogyi, A.; Major, T.; Fodor, J.; Nemeth, G. [Dept. of Radiotherapy, National Inst. of Oncology, Budapest (Hungary); Oberna, F. [Dept. of Maxillofacial Surgery, St. Rokus Hospital, Budapest (Hungary); Remenar, E.; Kasler, M. [Dept. of Head and Neck, Maxillofacial and Reconstructive Plastic Surgery, National Inst. of Oncology, Budapest (Hungary)

    2004-12-01

    Background and purpose: to date none of the studies examined the feasibility and efficacy of interstitial high-dose-rate (HDR) brachytherapy in the treatment of carcinoma of the tongue base. Therefore the aim of this study was to contribute to this issue. Patients and methods: between 1992 and 2000 37 patients (mean age 55 years) with T1-4 and NO-3 carcinoma of the base of tongue were presented. Neck dissection was carried out in twelve cases (32%). 30 patients with advanced stage received brachytherapy boost after 50-66.5 Gy (mean, 60 Gy) locoregional external beam irradiation (EBI) and 7 patients with early stage (T1-2, NO) were managed locally with wide tumor excision and sole brachytherapy. 4 of them underwent neck dissection and the others were subjected to 50 Gy regional EBI. The mean dose of boost and sole brachytherapy was 18 Gy and 28 Gy, respectively. Results: the median follow-up time for surviving patients was 51 months. The 7 sole brachytherapy patients are living with no evidence of disease. For patients treated with EBI and brachytherapy boost, the 5-year actuarial rate of local, locoregional recurrence-free and overall survival was 60%, 52% and 46%, respectively. For all patients in univariate analysis larger tumor size (T4 vs. T1-3) was significant negative predictor of local (RR: 7.23) and locoregional control (RR: 3.87), but nodal involvement was not. Delayed soft tissue ulceration and osteoradionecrosis occurred in 4 (13%) EBI and brachytherapy treated patients. None of the sole brachytherapy patients experienced severe late radiation toxicity. Conclusion: EBI combined with interstitial HDR brachytherapy boost result in acceptable local tumor control with low incidence of late side effects in patients with advanced disease. Fractionated sole HDR brachytherapy following tumor excision is a feasible treatment option for patients with early stage cancer and gives excellent local results. (orig.)

  7. On the use of Kodak CR film for quality assurance of needle loading in I-125 seed prostate brachytherapy.

    Science.gov (United States)

    Fog, L S; Nicholls, R; van Doom, T

    2007-09-01

    Low dose rate brachytherapy using implanted I-125 seeds as a monotherapy for prostate cancer is now in use in many hospitals. In contrast to fractionated brachytherapy treatments, where the effect of incorrect positioning of the source in one treatment fraction can be diminished by correcting the position in subsequent fractions, the I-125 seed implant is permanent, making correct positioning of the seeds in the prostate essential. The seeds are inserted into the prostate using needles. Correct configuration of seeds in the needles is essential in order to deliver the planned treatment. A comparison of an autoradiograph obtained by exposing film to the seed-loaded needles with the patient treatment plan is a valuable quality assurance tool. However, the time required to sufficiently expose Kodak XOMAT V film, currently used in this department is significant. This technical note presents the use of Kodak CR film for acquisition of the radiograph. The digital radiograph can be acquired significantly faster, has superior signal-to-noise ratio and contrast and has the usual benefits of digital film, e.g. a processing time which is shorter than that required for non-digital film, the possibility of image manipulation, possibility of paper printing and electronic storage.

  8. Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Damast, Shari, E-mail: shari.damast@yale.edu [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Alektiar, Kaled M. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Goldfarb, Shari [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Eaton, Anne; Patil, Sujata [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Mosenkis, Jeffrey [Department of Comparative Human Development, University of Chicago, Chicago, Illinois (United States); Bennett, Antonia [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Atkinson, Thomas [Department of Psychiatry, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Basch, Ethan [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-10-01

    Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from <6 months to >5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, based on the published validation study. Results: SD was reported by 81% of respondents. The mean ({+-} standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 ({+-}2.0); orgasm, 2.5 ({+-}2.4); desire, 2.4 ({+-}1.3); arousal, 2.2 ({+-}2.0); dryness, 2.1 ({+-}2.1); and pain, 1.9 ({+-}2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, -7.1 points; 95% CI, -11.2 to -3.1; P<.001), lack of vaginal lubricant use (effect size, -4.4 points; 95% CI, -8.7 to -0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, -4.6 points; 95% CI, -9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.

  9. Sexual Functioning Among Endometrial Cancer Patients Treated With Adjuvant High-Dose-Rate Intra-Vaginal Radiation Therapy

    International Nuclear Information System (INIS)

    Damast, Shari; Alektiar, Kaled M.; Goldfarb, Shari; Eaton, Anne; Patil, Sujata; Mosenkis, Jeffrey; Bennett, Antonia; Atkinson, Thomas; Jewell, Elizabeth; Leitao, Mario; Barakat, Richard; Carter, Jeanne; Basch, Ethan

    2012-01-01

    Purpose: We used the Female Sexual Function Index (FSFI) to investigate the prevalence of sexual dysfunction (SD) and factors associated with diminished sexual functioning in early stage endometrial cancer (EC) patients treated with simple hysterectomy and adjuvant brachytherapy. Methods and Materials: A cohort of 104 patients followed in a radiation oncology clinic completed questionnaires to quantify current levels of sexual functioning. The time interval between hysterectomy and questionnaire completion ranged from 5 years. Multivariate regression was performed using the FSFI as a continuous variable (score range, 1.2-35.4). SD was defined as an FSFI score of <26, based on the published validation study. Results: SD was reported by 81% of respondents. The mean (± standard deviation) domain scores in order of highest-to-lowest functioning were: satisfaction, 2.9 (±2.0); orgasm, 2.5 (±2.4); desire, 2.4 (±1.3); arousal, 2.2 (±2.0); dryness, 2.1 (±2.1); and pain, 1.9 (±2.3). Compared to the index population in which the FSFI cut-score was validated (healthy women ages 18-74), all scores were low. Compared to published scores of a postmenopausal population, scores were not statistically different. Multivariate analysis isolated factors associated with lower FSFI scores, including having laparotomy as opposed to minimally invasive surgery (effect size, −7.1 points; 95% CI, −11.2 to −3.1; P<.001), lack of vaginal lubricant use (effect size, −4.4 points; 95% CI, −8.7 to −0.2, P=.040), and short time interval (<6 months) from hysterectomy to questionnaire completion (effect size, −4.6 points; 95% CI, −9.3-0.2; P=.059). Conclusions: The rate of SD, as defined by an FSFI score <26, was prevalent. The postmenopausal status of EC patients alone is a known risk factor for SD. Additional factors associated with poor sexual functioning following treatment for EC included receipt of laparotomy and lack of vaginal lubricant use.

  10. The dosimetry of prostate brachytherapy-induced urethral strictures

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Butler, Wayne M.; Tollenaar, Bryan G.; Galbreath, Robert W.; Lief, Jonathan H.

    2002-01-01

    Purpose: There is a paucity of data regarding the incidence of urethral strictures after prostate brachytherapy. In this study, we evaluate multiple clinical, treatment, and dosimetric parameters to identify factors associated with the development of brachytherapy-induced urethral strictures. Methods and Materials: 425 patients underwent transperineal ultrasound-guided prostate brachytherapy using either 103 Pd or 125 I for clinical T1b/T3a NxM0 (1997, American Joint Committee on Cancer) adenocarcinoma of the prostate gland from April 1995 to October 1999. No patient was lost to follow-up. 221 patients were implanted with 103 Pd and 204 patients with 125 I. The median patient age was 68 years (range 48-81 years). The median follow-up was 35.2 months (range 15-72 months). Follow-up was calculated from the day of implantation. Thirteen patients developed brachytherapy-induced strictures, and all strictures involved the membranous urethra. A control group of 35 patients was rigorously matched to the stricture patients in terms of treatment approach; i.e., choice of isotope, plus or minus radiation therapy, and plus or minus hormonal manipulation. Nine of the 13 stricture patients had detailed Day 0 urethral dosimetry available for review. The apex of the prostate gland and the membranous urethra were defined by CT evaluation. Urethral dosimetry was reported for the prostatic urethra, the apical slice of the prostate gland, and the membranous urethra which was defined as extending 20 mm in length. Results: The 5-year actuarial risk of a urethral stricture was 5.3%, with a median time to development of 26.6 months (range 7.8-44.1 months). Of multiple clinical and treatment parameters evaluated, only the duration of hormonal manipulation (>4 months, p=0.011) was predictive for the development of a urethral stricture. The radiation dose to the membranous urethra was significantly greater in patients with strictures than those without: 97.6%±20.8% vs. 81.0%±19.8% of

  11. High-dose-rate brachytherapy in uterine cervical carcinoma

    International Nuclear Information System (INIS)

    Patel, Firuza D.; Rai, Bhavana; Mallick, Indranil; Sharma, Suresh C.

    2005-01-01

    Purpose: High-dose-rate (HDR) brachytherapy is in wide use for curative treatment of cervical cancer. The American Brachytherapy Society has recommended that the individual fraction size be <7.5 Gy and the range of fractions should be four to eight; however, many fractionation schedules, varying from institution to institution, are in use. We use 9 Gy/fraction of HDR in two to five fractions in patients with carcinoma of the uterine cervix. We found that our results and toxicity were comparable to those reported in the literature and hereby present our experience with this fractionation schedule. Methods and Materials: A total of 121 patients with Stage I-III carcinoma of the uterine cervix were treated with HDR brachytherapy between 1996 and 2000. The total number of patients analyzed was 113. The median patient age was 53 years, and the histopathologic type was squamous cell carcinoma in 93% of patients. The patients were subdivided into Groups 1 and 2. In Group 1, 18 patients with Stage Ib-IIb disease, tumor size <4 cm, and preserved cervical anatomy underwent simultaneous external beam radiotherapy to the pelvis to a dose of 40 Gy in 20 fractions within 4 weeks with central shielding and HDR brachytherapy of 9 Gy/fraction, given weekly, and interdigitated with external beam radiotherapy. The 95 patients in Group 2, who had Stage IIb-IIIb disease underwent external beam radiotherapy to the pelvis to a dose of 46 Gy in 23 fractions within 4.5 weeks followed by two sessions of HDR intracavitary brachytherapy of 9 Gy each given 1 week apart. The follow-up range was 3-7 years (median, 36.4 months). Late toxicity was graded according to the Radiation Therapy Oncology Group criteria. Results: The 5-year actuarial local control and disease-free survival rate was 74.5% and 62.0%, respectively. The actuarial local control rate at 5 years was 100% for Stage I, 80% for Stage II, and 67.2% for Stage III patients. The 5-year actuarial disease-free survival rate was 88.8% for

  12. Interstitial brachytherapy for eyelid carcinoma. Outcome analysis in 60 patients

    Energy Technology Data Exchange (ETDEWEB)

    Krengli, M.; Deantonio, L. [University Hospital ' ' Maggiore della Carita' ' , Division of Radiotherapy, Novara (Italy); University of ' ' Piemonte Orientale' ' , Department of Translational Medicine, Novara (Italy); Masini, L.; Filomeno, A.; Gambaro, G. [University Hospital ' ' Maggiore della Carita' ' , Division of Radiotherapy, Novara (Italy); Comoli, A.M. [University Hospital Maggiore della Carita, Ophthalmology, Novara (Italy); Negri, E. [University Hospital Maggiore della Carita, Medical Physics, Novara (Italy)

    2014-03-15

    Eyelid cancer is a therapeutic challenge due to the cosmetic and functional implications of this anatomical region and the objectives of therapy are tumor control, functional and cosmetic outcome. The present study was performed to analyze local control, toxicity, functional and cosmetic results in patients with eyelid carcinoma treated by interstitial brachytherapy. In this study 60 patients with eyelid carcinoma were treated by interstitial brachytherapy using iridium ({sup 192}Ir) wires with a linear activity of 1.2-1.7 mCi/cm. The prescription dose was 51-70 Gy (mean 65 Gy, median 66 Gy). Of the 60 patients 51 (85.0 %) had received no prior treatment, 4 (6.7 %) had received previous surgery with positive or close margins and 5 (8.3 %) had suffered local recurrence after surgery. Of the tumors 52 (86.7 %) were basal cell carcinoma, 7 (11.7 %) squamous cell carcinoma and 1 (1.7 %) Merkel cell carcinoma. Clinical stage of the 51 previously untreated tumors was 38 T1N0, 12 T2N0 and 1 T3N0. Mean follow-up was 92 months (range 6-253 months). Local control was maintained in 96.7 % of patients. Late effects higher than grade 2 were observed in 3.0 % of cases. Functional and cosmetic outcomes were optimal in 68.4 % of patients. Interstitial brachytherapy for carcinoma of the eyelid can achieve local control, cosmetic and functional results comparable to those of surgery. (orig.) [German] Das Karzinom des Augenlids stellt aufgrund der funktionellen und kosmetischen Beeintraechtigungen dieser anatomischen Region eine therapeutische Herausforderung dar. Ziele der Therapie sind sowohl die Tumorkontrolle als auch ein gutes funktionelles und kosmetisches Ergebnis. Lokale Kontrolle, Toxizitaet sowie funktionelle und kosmetische Ergebnisse bei Patienten mit Karzinom des Augenlids, die mit interstitieller Brachytherapie behandelt wurden, sollten analysiert werden. Sechzig Patienten mit Karzinom des Augenlids wurden mit interstitieller Brachytherapie mit Iridium-192-Draehten

  13. Brachytherapy reconstruction using orthogonal scout views from the CT

    International Nuclear Information System (INIS)

    Perez, J.; Lliso, F.; Carmona, V.; Bea, J.; Tormo, A.; Petschen, I.

    1996-01-01

    Introduction: CT assisted brachytherapy planning is demonstrating to have great advantages as external RT planning does. One of the problems we have found in this approach with the conventional gynecological Fletcher applicators is the high amount of artefacts (ovoids with rectal and vessical protections) in the CT slice. We have introduced a reconstruction method based on scout views in order to avoid this problem, allowing us to perform brachytherapy reconstruction completely CT assisted. We use a virtual simulation chain by General Electric Medical Systems. Method and discussion: Two orthogonal scout views (0 and 90 tube positions) are performed. The reconstruction method takes into account the virtual position of the focus and the fact that there is only divergence in the transverse plane. Algorithms developed for sources as well as for reference points localisation (A, B, lymphatic Fletcher trapezoid, pelvic wall, etc.) are presented. This method has the following practical advantages: the porte-cassette is not necessary, the image quality can be improved (it is very helpful in pelvic lateral views that are critical in conventional radiographs), the total time to get the data is smaller than for conventional radiographs (reduction of patient motion effects) and problems that appear in CT-slice based reconstruction in the case of strongly curved intrauterine applicators are avoided. Even though the resolution is smaller than in conventional radiographs it is good enough for brachytherapy. Regarding the CT planning this method presents the interesting feature that the co-ordinate system is the same for the reconstruction process that for the CT-slices set. As the application can be reconstructed from scout views and the doses can be evaluated on CT slices it is easier to correlate the dose values obtained for the traditional points with those provided by the CT information

  14. 'Homogeneity in brachytherapy' - Dummy run experience in Belgium

    International Nuclear Information System (INIS)

    Methords

    1996-01-01

    Purpose: The homogeneity of brachytherapy treatments in Belgium was appreciated through a dummy run with two fictive patients. Materiel and Methods: All members of the Belgian Brachytherapy Board received last year a questionnaire about treatment technique, technical approach, dosimetry and treatment planning, for 2 selected clinical histories. Case 1: T1 G1 NO MO - SCC of the lateral border of the mobile tongue (dimensions: 12x10x5mm). Case 2: T1 G1 NO MO - SCC of the lateral side of the nose (10x12x3mm). Results: 10 members out of 14 from the Belgian Brachytherapy Board returned their questionnaire. Little variation has been observed regarding treatment technique, technical approach (H and N: hairpins or loops, skin: plastic tubes), dose (60-65 Gy), activity of Ir-192 (1-2 mCi/cm), definition of Gross Tumor Volume and dosimetry (Paris System). On the contrary, a large difference was observed in the definition of the Clinical Target Volume and the Treated Volume. Despite of this large difference, the ratio treated volume on clinical target volume was always satisfactory (1,2 for skin cancer - 2 for H and N cancer), indicating that the treatment was well adapted to the Clinical Target Volume in all but 1 instance. Variations of a factor 2 in the dose rate of irradiation were tolerated (40-80 cGy/h). Conclusion: Rigid guidelines are mostly followed by the responders concerning dose, dose prescription and implantation techniques. Large variations are encountered concerning safety margins (Clinical Target definition) and dose rate

  15. Prostate Brachytherapy in Men ≥75 Years of Age

    International Nuclear Information System (INIS)

    Merrick, Gregory S.; Wallner, Kent E.; Galbreath, Robert W.; Butler, Wayne M.; Brammer, Sarah G.; Allen, Zachariah A.; Adamovich, Edward

    2008-01-01

    Purpose: To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged ≥75 years undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and August 2004, 145 consecutive patients aged ≥75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level ≤0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival. Results: Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer. Conclusions: After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients

  16. Dose rate constant and energy spectrum of interstitial brachytherapy sources

    International Nuclear Inform