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Sample records for assessing four-dimensional radiotherapy

  1. Prostate displacement during transabdominal ultrasound image-guided radiotherapy assessed by real-time four-dimensional transperineal monitoring

    DEFF Research Database (Denmark)

    Baker, Mariwan; Behrens, Claus F.

    2015-01-01

    Background. Transabdominal ultrasound (TAUS) imaging is currently available for localizing the prostate in daily image-guided radiotherapy (IGRT). The aim of this study was to determine the induced prostate displacement during such TAUS imaging. The prostate displacement was monitored using a nov...

  2. Four-dimensional imaging in radiotherapy for lung cancer patients

    NARCIS (Netherlands)

    Wolthaus, J.W.H.

    2009-01-01

    Lung cancer is the most common cause of cancer related death. Overall survival is often poor after treatment with conventional radiotherapy. Improvements may be obtained by increasing the radiation dose; however, this can lead to unacceptable complications of healthy organs in or near the

  3. A novel four-dimensional radiotherapy method for lung cancer: imaging, treatment planning and delivery

    Energy Technology Data Exchange (ETDEWEB)

    Alasti, H [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Cho, Y B [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Vandermeer, A D [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Abbas, A [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Norrlinger, B [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Shubbar, S [Department of Radiation Oncology, Princess Margaret Hospital, Toronto, ON (Canada); Bezjak, A [Department of Radiation Oncology, University of Toronto, Toronto, ON (Canada)

    2006-06-21

    We present treatment planning methods based on four-dimensional computed tomography (4D-CT) to incorporate tumour motion using (1) a static field and (2) a dynamic field. Static 4D fields are determined to include the target in all breathing phases, whereas dynamic 4D fields are determined to follow the shape of the tumour assessed from 4D-CT images with a dynamic weighting factor. The weighting factor selection depends on the reliability of patient breathing and limitations of the delivery system. The static 4D method is compared with our standard protocol for gross tumour volume (GTV) coverage, mean lung dose and V20. It was found that the GTV delineated on helical CT without incorporating breathing motion does not adequately represent the target compared to the GTV delineated from 4D-CT. Dosimetric analysis indicates that the static 4D-CT based technique results in a reduction of the mean lung dose compared with the standard protocol. Measurements on a moving phantom and simulations indicated that 4D radiotherapy (4D-RT) synchronized with respiration-induced motion further reduces mean lung dose and V20, and may allow safe application of dose escalation and CRT/IMRT. The motions of the chest cavity, tumour and thoracic structures of 24 lung cancer patients are also analysed.

  4. Four-dimensional dose evaluation using deformable image registration in radiotherapy for liver cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hoon Jung, Sang; Min Yoon, Sang; Ho Park, Sung; Cho, Byungchul; Won Park, Jae; Jung, Jinhong; Park, Jin-hong; Hoon Kim, Jong; Do Ahn, Seung [Departments of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul 138-736 (Korea, Republic of)

    2013-01-15

    Purpose: In order to evaluate the dosimetric impact of respiratory motion on the dose delivered to the target volume and critical organs during free-breathing radiotherapy, a four-dimensional dose was evaluated using deformable image registration (DIR). Methods: Four-dimensional computed tomography (4DCT) images were acquired for 11 patients who were treated for liver cancer. Internal target volume-based treatment planning and dose calculation (3D dose) were performed using the end-exhalation phase images. The four-dimensional dose (4D dose) was calculated based on DIR of all phase images from 4DCT to the planned image. Dosimetric parameters from the 4D dose, were calculated and compared with those from the 3D dose. Results: There was no significant change of the dosimetric parameters for gross tumor volume (p > 0.05). The increase D{sub mean} and generalized equivalent uniform dose (gEUD) for liver were by 3.1%{+-} 3.3% (p= 0.003) and 2.8%{+-} 3.3% (p= 0.008), respectively, and for duodenum, they were decreased by 15.7%{+-} 11.2% (p= 0.003) and 15.1%{+-} 11.0% (p= 0.003), respectively. The D{sub max} and gEUD for stomach was decreased by 5.3%{+-} 5.8% (p= 0.003) and 9.7%{+-} 8.7% (p= 0.003), respectively. The D{sub max} and gEUD for right kidney was decreased by 11.2%{+-} 16.2% (p= 0.003) and 14.9%{+-} 16.8% (p= 0.005), respectively. For left kidney, D{sub max} and gEUD were decreased by 11.4%{+-} 11.0% (p= 0.003) and 12.8%{+-} 12.1% (p= 0.005), respectively. The NTCP values for duodenum and stomach were decreased by 8.4%{+-} 5.8% (p= 0.003) and 17.2%{+-} 13.7% (p= 0.003), respectively. Conclusions: The four-dimensional dose with a more realistic dose calculation accounting for respiratory motion revealed no significant difference in target coverage and potentially significant change in the physical and biological dosimetric parameters in normal organs during free-breathing treatment.

  5. Tumor motion in lung cancers: An overview of four-dimensional radiotherapy treatment of lung cancers

    Directory of Open Access Journals (Sweden)

    Anusheel Munshi

    2017-01-01

    Full Text Available Most modern radiotherapy centers have adopted contouring based treatment. Sparing of the normal structures has been made more achievable than ever before by use of technologies such as Intensity Modulated Radiotherapy (IMRT and Image guided radiotherapy (IGRT. However, unlike, sites such as brain or head neck, thorax is a site in active motion, mostly contributed by patient's respiratory movement. 4 D radiotherapy, that addresses the issues of motion in thoracic tumours answers this critical question. The present article outlines the scope of need for 4 D radiotherapy and discusses the options available for 4 D treatments of cancer patients.

  6. Monte Carlo as a four-dimensional radiotherapy treatment-planning tool to account for respiratory motion

    Science.gov (United States)

    Keall, P. J.; Siebers, J. V.; Joshi, S.; Mohan, R.

    2004-08-01

    Four-dimensional (4D) radiotherapy is the explicit inclusion of the temporal changes in anatomy during the imaging, planning and delivery of radiotherapy. Temporal anatomic changes can occur for many reasons, though the focus of the current investigation was respiration motion for lung tumours. The aims of the current research were first to develop a 4D Monte Carlo methodology and second to apply this technique to an existing 4D treatment plan. A 4D CT scan consisting of a series of 3D CT image sets acquired at different respiratory phases was used. Deformable image registration was performed to map each CT set from the end-inhale respiration phase to the CT image sets corresponding with subsequent respiration phases. This deformable registration allowed the contours drawn on the end-inhale CT to be automatically drawn on the other respiratory phase CT image sets. A treatment plan was created on the end-inhale CT image set and then automatically created on each of the 3D CT image sets corresponding with subsequent respiration phases, based on the beam arrangement and dose prescription in the end-inhale plan. Dose calculation using Monte Carlo was simultaneously performed on each of the N (=8) 3D image sets with 1/N fewer particles per calculation than for a 3D plan. The dose distribution from each respiratory phase CT image set was mapped back to the end-inhale CT image set for analysis. This use of deformable image registration to merge all the statistically noisy dose distributions back onto one CT image set effectively yielded a 4D Monte Carlo calculation with a statistical uncertainty equivalent to a 3D calculation, with a similar calculation time for the 3D and 4D methods. Monte Carlo as a dose calculation tool for 4D radiotherapy planning has two advantages: (1) higher accuracy for calculation in electronic disequilibrium conditions, such as those encountered during lung radiotherapy, and (2) if deformable image registration is used, the calculation time for

  7. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients

    NARCIS (Netherlands)

    Wolthaus, Jochem W. H.; Schneider, Christoph; Sonke, Jan-Jakob; van Herk, Marcel; Belderbos, José S. A.; Rossi, Maddalena M. G.; Lebesque, Joos V.; Damen, Eugène M. F.

    2006-01-01

    PURPOSE: Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple,

  8. Dynamic four-dimensional computed tomography for preoperative assessment of lung cancer invasion into adjacent structures†.

    Science.gov (United States)

    Choong, Cliff K C; Pasricha, Sundeep S; Li, Xun; Briggs, Peter; Ramdave, Shakher; Crossett, Marcus; Troupis, John M

    2015-02-01

    The 320-slice computed tomography (CT) provides three-dimensional and dynamic imaging resulting in the ability to assess motion analysis between two adjacent structures (the fourth dimension). Differential movements between two adjacent structures would indicate that there is no fixation between the two structures. Eight patients with non-small-cell lung cancers located adjacent to vital structures (e.g. the great vessels) (n = 4), mediastinum (n = 1) or chest wall (n = 3) where conventional CT was unable to exclude local invasion underwent dynamic four-dimensional (4D) CT assessment. In 3 patients, the lung tumour was abutting the chest wall and 1 patient had tumour abutting the mediastinum. The remaining patients included a patient with a large 14-cm left lower lobe cancer abutting the descending thoracic aorta who had previous pleurodesis; a patient with an apical right upper lobe 6-cm cancer with static imaging appearances suggestive of tumour invasion into the apex, the mediastinal surface and superior vena cava (SVC); a patient with a 3.5-cm cancer which had a broad 2.5-cm base abutting the distal aortic arch and a patient with a 14-cm left upper lobe cancer abutting the aortic arch, descending thoracic aorta and chest wall. Differential movements between the tumour and adjacent structure on 4D CT were considered indicative of the absence of frank invasion. Dynamic 4D imaging revealed differential movements between the tumour and the adjacent structures in 7 cases, suggesting the absence of overt malignant invasion. Intraoperative assessments confirmed the findings. In 1 case, a small area of fixation seen on dynamic CT corresponded intraoperatively to superficial invasion of the adventitia of the SVC. Dynamic 4D 320-slice CT is useful in the preoperative assessment of the direct invasion of lung cancer into adjacent structures and hence its resectability. © The Author 2014. Published by Oxford University Press on behalf of the European Association for

  9. SU-E-J-110: Dosimetric Analysis of Respiratory Motion Based On Four-Dimensional Dose Accumulation in Liver Stereotactic Body Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kang, S; Kim, D; Kim, T; Kim, K; Cho, M; Shin, D; Suh, T [The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of); Kim, S [Virginia Commonwealth University, Richmond, VA (United States); Park, S [Uijeongbu St.Mary’s Hospital, GyeongGi-Do (Korea, Republic of)

    2015-06-15

    Purpose: Respiratory motion in thoracic and abdominal region could lead to significant underdosing of target and increased dose to healthy tissues. The aim of this study is to evaluate the dosimetric effect of respiratory motion in conventional 3D dose by comparing 4D deformable dose in liver stereotactic body radiotherapy (SBRT). Methods: Five patients who had previously treated liver SBRT were included in this study. Four-dimensional computed tomography (4DCT) images with 10 phases for all patients were acquired on multi-slice CT scanner (Siemens, Somatom definition). Conventional 3D planning was performed using the average intensity projection (AIP) images. 4D dose accumulation was calculated by summation of dose distribution for all phase images of 4DCT using deformable image registration (DIR) . The target volume and normal organs dose were evaluated with the 4D dose and compared with those from 3D dose. And also, Index of achievement (IOA) which assesses the consistency between planned dose and prescription dose was used to compare target dose distribution between 3D and 4D dose. Results: Although the 3D dose calculation considered the moving target coverage, significant differences of various dosimetric parameters between 4D and 3D dose were observed in normal organs and PTV. The conventional 3D dose overestimated dose to PTV, however, there was no significant difference for GTV. The average difference of IOA which become ‘1’ in an ideal case was 3.2% in PTV. The average difference of liver and duodenum was 5% and 16% respectively. Conclusion: 4D dose accumulation which can provide dosimetric effect of respiratory motion has a possibility to predict the more accurate delivered dose to target and normal organs and improve treatment accuracy. This work was supported by the Radiation Technology R&D program (No. 2013M2A2A7043498) and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the

  10. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients.

    Science.gov (United States)

    Wolthaus, Jochem W H; Schneider, Christoph; Sonke, Jan-Jakob; van Herk, Marcel; Belderbos, José S A; Rossi, Maddalena M G; Lebesque, Joos V; Damen, Eugène M F

    2006-08-01

    Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple, new concept to incorporate patient-specific motion information, using 4D-CT scans, in the radiotherapy planning process of lung cancer patients to enable smaller error margins. A single CT scan was selected from the 4D-CT data set. This scan represented the tumor in its time-averaged position over the respiratory cycle (the mid-ventilation CT scan). To select the appropriate CT scan, two methods were used. First, the three-dimensional tumor motion was analyzed semiautomatically to calculate the mean tumor position and the corresponding respiration phase. An alternative automated method was developed to select the correct CT scan using the diaphragm motion. Owing to hysteresis, mid-ventilation selection using the three-dimensional tumor motion had a tumor position accuracy (with respect to the mean tumor position) better than 1.1 +/- 1.1 mm for all three directions (inhalation and exhalation). The accuracy in the diaphragm motion method was better than 1.1 +/- 1.1 mm. Conventional free-breathing CT scanning had an accuracy better than 0 +/- 3.9 mm. The mid-ventilation concept can result in an average irradiated volume reduction of 20% for tumors with a diameter of 40 mm. Tumor motion and the diaphragm motion method can be used to select the (artifact-free) mid-ventilation CT scan, enabling a significant reduction of the irradiated volume.

  11. Development of an ultrasmall C-band linear accelerator guide for a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head.

    Science.gov (United States)

    Kamino, Yuichiro; Miura, Sadao; Kokubo, Masaki; Yamashita, Ichiro; Hirai, Etsuro; Hiraoka, Masahiro; Ishikawa, Junzo

    2007-05-01

    We are developing a four-dimensional image-guided radiotherapy system with a gimbaled x-ray head. It is capable of pursuing irradiation and delivering irradiation precisely with the help of an agile moving x-ray head on the gimbals. Requirements for the accelerator guide were established, system design was developed, and detailed design was conducted. An accelerator guide was manufactured and basic beam performance and leakage radiation from the accelerator guide were evaluated at a low pulse repetition rate. The accelerator guide including the electron gun is 38 cm long and weighs about 10 kg. The length of the accelerating structure is 24.4 cm. The accelerating structure is a standing wave type and is composed of the axial-coupled injector section and the side-coupled acceleration cavity section. The injector section is composed of one prebuncher cavity, one buncher cavity, one side-coupled half cavity, and two axial coupling cavities. The acceleration cavity section is composed of eight side-coupled nose reentrant cavities and eight coupling cavities. The electron gun is a diode-type gun with a cerium hexaboride (CeB6) direct heating cathode. The accelerator guide can be operated without any magnetic focusing device. Output beam current was 75 mA with a transmission efficiency of 58%, and the average energy was 5.24 MeV. Beam energy was distributed from 4.95 to 5.6 MeV. The beam profile, measured 88 mm from the beam output hole on the axis of the accelerator guide, was 0.7 mm X 0.9 mm full width at half maximum (FWHM) width. The beam loading line was 5.925 (MeV)-Ib (mA) X 0.00808 (MeV/mA), where Ib is output beam current. The maximum radiation leakage of the accelerator guide at 100 cm from the axis of the accelerator guide was calculated as 0.33 cGy/min at the rated x-ray output of 500 cGy/min from the measured value. This leakage requires no radiation shielding for the accelerator guide itself per IEC 60601-2-1.

  12. Assessing psychological health in midwifery practice: A validation study of the Four-Dimensional Symptom Questionnaire (4DSQ), a Dutch primary care instrument

    NARCIS (Netherlands)

    Tebbe, B.B.M.; Terluin, B.; Koelewijn, J.M.

    2013-01-01

    Objective: the Four-Dimensional Symptom Questionnaire (4DSQ) is a validated self-report questionnaire, developed for general practice to assess the level of distress, somatization, depression and anxiety among patients. This study evaluated the validity of this instrument for midwifery practice by

  13. Analysis of environmental and general science efficacy among instructors with contrasting class ethnicity distributions: A four-dimensional assessment

    Science.gov (United States)

    Taylor, Bryan Keith

    Scope and method of study. The context and nature of self-efficacy beliefs provides a vector upon which to explore science instructors' perceptions of their own competence, self beliefs, and beliefs concerning their students as a function of ethnicity (Pajares, 1996). Currently, available cross-sectional data that concomitantly compares efficacy for environmental and general science curricula among instructors with contrasting class ethnicity distributions (CED) (minority vs. non-minority) is diminutive. Here, a modified research instrument that incorporates the Environmental Education Efficacy Belief Instrument (Sia, 1992), the Science Teaching Efficacy Beliefs Instrument (Riggs & Enochs, 1990), and factors 2 & 3 from the Ohio State Teacher Efficacy Scale (Tschannen-Moran & Hoy, 2001) is employed to create a bi-disciplinary four dimensional assessment that measures personal teacher efficacy (PTE), outcome expectancy (OE), classroom management (CM), and student engagement (SE). Instructors' willingness to, and utilization of, practical instruction to reinforce science learning is also assessed. Findings and conclusions. Overall, efficacy levels for environmental and general science curriculum among instructors with high minority CED (n=22) were consistently lower than that of instructors with high non-minority CED (n = 18); consistently diminished efficacy levels were evidenced upon analysis of CED and all independent variables analyzed. While all four dimensions of efficacy were consistently low for instructors with high minority CED, markedly low mean CM and SE responses were evidenced. A link exists between teacher self-efficacy and the conditions present that impinge on the successful completion of work goals (Metz, 1978). Many studies have examined the lowered-level of minority involvement in environmental careers, issues, and concerns (Taylor, 1989). While all science instructors were willing to utilize outdoor classrooms, markedly lower outdoor classroom

  14. Four Dimensional Cardiac Imaging

    Science.gov (United States)

    Smith, L. D. R.; Quarendon, P.

    1986-05-01

    A system for the production of a four dimensional (moving three dimensional) human epicardial left ventriculogram, modelled and highlighted to show regional wall motion changes, is described. The moving image is derived by fitting a surface to the three dimensional coordinates of coronary artery bifurcations. These are determined by analysis of digitised biplane coronary cineangiograms. This image system not only provides a unique 3-D view of left ventricular activity but might also provide measures of cardiac dynamics such as, stroke volume and velocity of wall movement. The system is not fully automated although operator interaction may be minimised. Further work on vessel tracking systems is required before full automation is possible.

  15. On four dimensional mirror symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Losev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Nekrasov, N.; Shatashvili, S.

    2000-07-01

    A conjecture relating instanton calculus in four dimensional supersymmetric theories and the deformation theory of Lagrangian submanifolds in C{sup 2r} invariant under a (subgroup of) Sp(2r,Z) is formulated. This is a four dimensional counterpart of the mirror symmetry of topological strings (relating Gromov-Witten invariants and generalized variations of Hodge structure). (orig.)

  16. Leadership as social identity management: Introducing the Identity Leadership Inventory (ILI) to assess and validate a four-dimensional model

    OpenAIRE

    Steffens, Niklas K.; Haslam, S. Alexander; Reicher, Stephen D.; Platow, Michael J.; Fransen, Katrien; Yang, Jie; Ryan, Michelle K.; Jetten, Jolanda; Peters, Kim; Boen, Filip

    2014-01-01

    Although nearly two decades of research has provided support for the social identity approach to leadership, most previous work has focused on leaders’ identity prototypicality while neglecting the assessment of other equally important dimensions of social identity management. However, recent theoretical developments have argued that in order to mobilize and direct followers’ energies, leaders need not only to ‘be one of us’ (identity prototypicality), but also to ‘do it for us’ (identity adv...

  17. Four-dimensional x-ray attenuation model of the human heart and the coronary vasculature for assessment of CT system capability

    Science.gov (United States)

    Edic, Peter M.; Iatrou, Maria; Cline, Harvey E.; Ishaque, A. N.; Cesmeli, Erdogan; Pfoh, Armin H.

    2001-06-01

    With the introduction of helical, multi-detector computed tomography (CT) scanners having sub-second scanning speeds, clinicians are currently investigating the role of CT in cardiac imaging. In this paper, we describe a four-dimensional (4D) x-ray attenuation model of a human heart and the use of this model to assess the capabilities of both hardware and software algorithms for cardiac imaging. We developed a model of the human thorax, composed of several analytical structures, and a model of the human heart, constructed from several elliptical surfaces. A model for each coronary vessel consists of a torus placed at a suitable location on the heart's surface. The motion of the heart during the cardiac cycle was implemented by applying transformational operators to each surface composing the heart. We used the 4D model of the heart to generate forward projection data, which then became input into a model of a CT imaging system. The use of the model to predict image quality is demonstrated by varying both the reconstruction algorithm (sector-based, half-scan) and CT system parameters (gantry speed, spatial resolution). The mathematical model of the human heart, while having limitations, provides a means to rapidly evaluate new reconstruction algorithms and CT system designs for cardiac imaging.

  18. The linguistic validation of Russian version of Dutch four-dimensional symptoms questionnaire (4DSQ) for assessing distress, depression, anxiety and somatization in patients with borderline psychosomatic disorders.

    Science.gov (United States)

    Arnautov, V S; Reyhart, D V; Smulevich, A B; Yakhno, N N; Terluin, B; Zakharova, E K; Andryushchenko, A V; Parfenov, V A; Zamergrad, M V; Romanov, D V

    2015-12-12

    The four-dimensional symptom questionnaire (4DSQ) is an originally Dutch self-report questionnaire that has been developed in primary care to distinguish non-specific general distress from depression, anxiety and somatization. In order to produce the appropriate translated Russian version the process of linguistic validation has been initiated. This process has been done according to the "Linguistic Validation Manual for Health Outcome Assessments" developed by MAPI institute. To produce the appropriate Russian version of the 4DSQ that is conceptually and linguistically equivalent to the original questionnaire. The original Dutch version of the 4DSQ was translated by one translator into Russian. The validated English version of the 4DSQ was translated by another translator into Russian without mutual consultation. The consensus version was created based on two translated versions. After that the back translation was performed to Dutch, some changes were implemented to the consensus Russian version and the second target version was developed based on these results. The second target version was sent to an appropriate group of reviewers. Based on their comments, the second target version was updated. After wards this version was tested in patients during cognitive interview. The study protocol was approved by the Independent Interdisciplinary Ethics Committee on Ethical Review for Clinical Studies, and in compliance with the Helsinki Declaration and ICH-GCP guidelines and local regulations. Enrolled patients provided written informed consent. After the process of forward and backward translation, consultant and developer's comments, clinicians and cognitive review the final version of Russian 4DSQ was developed for assessment of distress, depression, anxiety and somatization. The Russian 4DSQ as a result of translation procedures and cognitive interviews linguistically corresponds to the original Dutch 4DSQ and could be assessed in psychometric validation for the

  19. The Four-Dimensional Symptom Questionnaire (4DSQ): a validation study of a multidimensional self-report questionnaire to assess distress, depression, anxiety and somatization

    Science.gov (United States)

    Terluin, Berend; van Marwijk, Harm WJ; Adèr, Herman J; de Vet, Henrica CW; Penninx, Brenda WJH; Hermens, Marleen LM; van Boeijen, Christine A; van Balkom, Anton JLM; van der Klink, Jac JL; Stalman, Wim AB

    2006-01-01

    Background The Four-Dimensional Symptom Questionnaire (4DSQ) is a self-report questionnaire that has been developed in primary care to distinguish non-specific general distress from depression, anxiety and somatization. The purpose of this paper is to evaluate its criterion and construct validity. Methods Data from 10 different primary care studies have been used. Criterion validity was assessed by comparing the 4DSQ scores with clinical diagnoses, the GPs' diagnosis of any psychosocial problem for Distress, standardised psychiatric diagnoses for Depression and Anxiety, and GPs' suspicion of somatization for Somatization. ROC analyses and logistic regression analyses were used to examine the associations. Construct validity was evaluated by investigating the inter-correlations between the scales, the factorial structure, the associations with other symptom questionnaires, and the associations with stress, personality and social functioning. The factorial structure of the 4DSQ was assessed through confirmatory factor analysis (CFA). The associations with other questionnaires were assessed with Pearson correlations and regression analyses. Results Regarding criterion validity, the Distress scale was associated with any psychosocial diagnosis (area under the ROC curve [AUC] 0.79), the Depression scale was associated with major depression (AUC = 0.83), the Anxiety scale was associated with anxiety disorder (AUC = 0.66), and the Somatization scale was associated with the GPs' suspicion of somatization (AUC = 0.65). Regarding the construct validity, the 4DSQ scales appeared to have considerable inter-correlations (r = 0.35-0.71). However, 30–40% of the variance of each scale was unique for that scale. CFA confirmed the 4-factor structure with a comparative fit index (CFI) of 0.92. The 4DSQ scales correlated with most other questionnaires measuring corresponding constructs. However, the 4DSQ Distress scale appeared to correlate with some other depression scales more

  20. Four Dimensional Trace Space Measurement

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, M.

    2005-02-10

    Future high energy colliders and FELs (Free Electron Lasers) such as the proposed LCLS (Linac Coherent Light Source) at SLAC require high brightness electron beams. In general a high brightness electron beam will contain a large number of electrons that occupy a short longitudinal duration, can be focused to a small transverse area while having small transverse divergences. Therefore the beam must have a high peak current and occupy small areas in transverse phase space and so have small transverse emittances. Additionally the beam should propagate at high energy and have a low energy spread to reduce chromatic effects. The requirements of the LCLS for example are pulses which contain 10{sup 10} electrons in a temporal duration of 10 ps FWHM with projected normalized transverse emittances of 1{pi} mm mrad[1]. Currently the most promising method of producing such a beam is the RF photoinjector. The GTF (Gun Test Facility) at SLAC was constructed to produce and characterize laser and electron beams which fulfill the LCLS requirements. Emittance measurements of the electron beam at the GTF contain evidence of strong coupling between the transverse dimensions of the beam. This thesis explores the effects of this coupling on the determination of the projected emittances of the electron beam. In the presence of such a coupling the projected normalized emittance is no longer a conserved quantity. The conserved quantity is the normalized full four dimensional phase space occupied by the beam. A method to determine the presence and evaluate the strength of the coupling in emittance measurements made in the laboratory is developed. A method to calculate the four dimensional volume the beam occupies in phase space using quantities available in the laboratory environment is also developed. Results of measurements made of the electron beam at the GTF that demonstrate these concepts are presented and discussed.

  1. Cerebral Hemodynamics in Patients with Hemolytic Uremic Syndrome Assessed by Susceptibility Weighted Imaging and Four-Dimensional Non-Contrast MR Angiography.

    Directory of Open Access Journals (Sweden)

    Ulrike Löbel

    Full Text Available Conventional magnetic resonance imaging (MRI of patients with hemolytic uremic syndrome (HUS and neurological symptoms performed during an epidemic outbreak of Escherichia coli O104:H4 in Northern Europe has previously shown pathological changes in only approximately 50% of patients. In contrast, susceptibility-weighted imaging (SWI revealed a loss of venous contrast in a large number of patients. We hypothesized that this observation may be due to an increase in cerebral blood flow (CBF and aimed to identify a plausible cause.Baseline 1.5T MRI scans of 36 patients (female, 26; male, 10; mean age, 38.2±19.3 years were evaluated. Venous contrast was rated on standard SWI minimum intensity projections. A prototype four-dimensional (time resolved magnetic resonance angiography (4D MRA assessed cerebral hemodynamics by global time-to-peak (TTP, as a surrogate marker for CBF. Clinical parameters studied were hemoglobin, hematocrit, creatinine, urea levels, blood pressure, heart rate, and end-tidal CO2.SWI venous contrast was abnormally low in 33 of 36 patients. TTP ranged from 3.7 to 10.2 frames (mean, 7.9 ± 1.4. Hemoglobin at the time of MRI (n = 35 was decreased in all patients (range, 5.0 to 12.6 g/dL; mean, 8.2 ± 1.4; hematocrit (n = 33 was abnormally low in all but a single patient (range, 14.3 to 37.2%; mean, 23.7 ± 4.2. Creatinine was abnormally high in 30 of 36 patients (83% (range, 0.8 to 9.7; mean, 3.7 ± 2.2. SWI venous contrast correlated significantly with hemoglobin (r = 0.52, P = 0.0015, hematocrit (r = 0.65, P < 0.001, and TTP (r = 0.35, P = 0.036. No correlation of SWI with blood pressure, heart rate, end-tidal CO2, creatinine, and urea level was observed. Findings suggest that the loss of venous contrast is related to an increase in CBF secondary to severe anemia related to HUS. SWI contrast of patients with pathological conventional MRI findings was significantly lower compared to patients with normal MRI (mean SWI score, 1

  2. Matrix model formulation of four dimensional gravity

    Energy Technology Data Exchange (ETDEWEB)

    De Pietri, Roberto

    2001-03-01

    The attempt of extending to higher dimensions the matrix model formulation of two-dimensional quantum gravity leads to the consideration of higher rank tensor models. We discuss how these models relate to four dimensional quantum gravity and the precise conditions allowing to associate a four-dimensional simplicial manifold to Feynman diagrams of a rank-four tensor model.

  3. Spinors in Four-Dimensional Spaces

    CERN Document Server

    Torres del Castillo, Gerardo F

    2010-01-01

    Without using the customary Clifford algebras frequently studied in connection with the representations of orthogonal groups, this book gives an elementary introduction to the two-component spinor formalism for four-dimensional spaces with any signature. Some of the useful applications of four-dimensional spinors, such as Yang–Mills theory, are derived in detail using illustrative examples. Key topics and features: • Uniform treatment of the spinor formalism for four-dimensional spaces of any signature, not only the usual signature (+ + + −) employed in relativity • Examples taken from Riemannian geometry and special or general relativity are discussed in detail, emphasizing the usefulness of the two-component spinor formalism • Exercises in each chapter • The relationship of Clifford algebras and Dirac four-component spinors is established • Applications of the two-component formalism, focusing mainly on general relativity, are presented in the context of actual computations Spinors in Four-Dim...

  4. Assessment of post-radiotherapy salivary glands

    Science.gov (United States)

    Cheng, S C H; Wu, V W C; Kwong, D L W; Ying, M T C

    2011-01-01

    Salivary glands are usually irradiated during radiotherapy for head and neck cancers, which can lead to radiation-induced damage. Radiation-induced xerostomia (oral dryness) is the most common post-radiotherapy complication for head and neck cancer patients and can reduce the patient’s quality of life. Accurate and efficient salivary gland assessment methods provide a better understanding of the cause and degree of xerostomia, and may help in patient management. At present, there are different methods for the assessment of salivary gland hypofunction; however, none of them are considered to be standard procedure. This article reviews the value of common methods in the assessment of post-radiotherapy salivary glands. PMID:21511748

  5. Adding Four- Dimensional Data Assimilation (aka grid ...

    Science.gov (United States)

    Adding four-dimensional data assimilation (a.k.a. grid nudging) to MPAS.The U.S. Environmental Protection Agency is investigating the use of MPAS as the meteorological driver for its next-generation air quality model. To function as such, MPAS needs to operate in a diagnostic mode in much the same manner as the current meteorological driver, the Weather Research and Forecasting (WRF) model. The WRF operates in diagnostic mode using Four-Dimensional Data Assimilation, also known as "grid nudging". MPAS version 4.0 has been modified with the addition of an FDDA routine to the standard physics drivers to nudge the state variables for wind, temperature and water vapor towards MPAS initialization fields defined at 6-hour intervals from GFS-derived data. The results to be shown demonstrate the ability to constrain MPAS simulations to known historical conditions and thus provide the U.S. EPA with a practical meteorological driver for global-scale air quality simulations. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, decision-support tools, and models to be applied to media-specific or receptor-specific problem areas. CED uses modeling-based approaches to characterize exposures, evaluate fate and transport, and support environmental diagnostics/forensics with input from multiple data sources. It also develops media- and receptor-specific models, process models, and decision support tools for use bo

  6. Four-dimensional coherent electronic Raman spectroscopy

    Science.gov (United States)

    Harel, Elad

    2017-04-01

    The correlations between different quantum-mechanical degrees of freedom of molecular species dictate their chemical and physical properties. Generally, these correlations are reflected in the optical response of the system but in low-order or low-dimensionality measurement the signals are highly averaged. Here, we describe a novel four-dimensional coherent spectroscopic method that directly correlates within and between the manifold of electronic and vibrational states. The optical response theory is developed in terms of both resonant and non-resonant field-matter interactions. Using resonance to select coherences on specific electronic states creates opportunities to directly distinguish coherent dynamics on the ground and electronically excited potentials. Critically, this method is free from lower-order signals that have plagued other electronically non-resonant vibrational spectroscopies. The theory presented here compliments recent work on the experimental demonstration of the 4D spectroscopic method described. We highlight specific means by which non-trivial effects such as anharmonicity (diagonal and off-diagonal), mode-specific vibronic coupling, and curvature of the excited states manifest in different projections of the 4D spectrum.

  7. Quality assurance of radiotherapy and its clinical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Toshihiko [Osaka Univ., Suita (Japan). Graduate School of Medicine

    2002-12-01

    We investigated the clinical quality assurance (QA) of radiotherapy in Japan since 1981. The aim of this study was to establish the QA of a radiotherapy system and its clinical assessment in Japan. We introduced the Patterns of Care Study (PCS) into Japan to perform this study in 1996. The PCS is a retrospective study designed to establish the national practice for cancer patients during a specific period and should be a complementary study to a prospective randomized controlled study. We collected precise data for 4399 patients with carcinomas of the breast, cervix, esophagus, lung and prostate by means of external audits for 96 institutes from 1998 through 2001. Patients were randomly sampled with two-stage cluster sampling. We stratified 556 institutes into four categories according to the academic condition and annual number of radiotherapy patients. National and regional averages of various factors of radiotherapy could be calculated and were used to measure QA of radiotherapy. Using a standard score, we could compare the process of individual institutions with national averages and feed back the evaluation score to each institution. With a PCS process survey, we could observe the dissemination of the treatment method under evidence-based medicine from the prospective randomized controlled study. We proposed future prediction of the number of radiotherapy patients and a counter plan for equipment and personnel. The first US-Japan PCS Workshop was held at San Francisco in 2001. We could establish QA of a radiotherapy system using PCS 1995-97 in Japan. (author)

  8. Automated four-dimensional Monte Carlo workflow using log files and real-time motion monitoring

    DEFF Research Database (Denmark)

    Sibolt, Patrik; Cronholm, R.O.; Heath, E.

    2017-01-01

    With emerging techniques for tracking and gating methods in radiotherapy of lung cancer patients, there is an increasing need for efficient four-dimensional Monte Carlo (4DMC) based quality assurance (QA). An automated and flexible workflow for 4DMC QA, based on the 4DdefDOSXYZnrc user code, has...... been developed in python. The workflow has been tested and verified using an in-house developed dosimetry system comprised of a dynamic thorax phantom constructed for plastic scintillator dosimetry. The workflow is directly compatible with any treatment planning system and can also be triggered...

  9. Motion artifact detection in four-dimensional computed tomography images

    Science.gov (United States)

    Bouilhol, G.; Ayadi, M.; Pinho, R.; Rit, S.; Sarrut, D.

    2014-03-01

    Motion artifacts appear in four-dimensional computed tomography (4DCT) images because of suboptimal acquisition parameters or patient breathing irregularities. Frequency of motion artifacts is high and they may introduce errors in radiation therapy treatment planning. Motion artifact detection can be useful for image quality assessment and 4D reconstruction improvement but manual detection in many images is a tedious process. We propose a novel method to evaluate the quality of 4DCT images by automatic detection of motion artifacts. The method was used to evaluate the impact of the optimization of acquisition parameters on image quality at our institute. 4DCT images of 114 lung cancer patients were analyzed. Acquisitions were performed with a rotation period of 0.5 seconds and a pitch of 0.1 (74 patients) or 0.081 (40 patients). A sensitivity of 0.70 and a specificity of 0.97 were observed. End-exhale phases were less prone to motion artifacts. In phases where motion speed is high, the number of detected artifacts was systematically reduced with a pitch of 0.081 instead of 0.1 and the mean reduction was 0.79. The increase of the number of patients with no artifact detected was statistically significant for the 10%, 70% and 80% respiratory phases, indicating a substantial image quality improvement.

  10. Four-dimensional hilbert curves for R-trees

    DEFF Research Database (Denmark)

    Haverkort, Herman; Walderveen, Freek van

    2011-01-01

    Two-dimensional R-trees are a class of spatial index structures in which objects are arranged to enable fast window queries: report all objects that intersect a given query window. One of the most successful methods of arranging the objects in the index structure is based on sorting the objects...... according to the positions of their centers along a two-dimensional Hilbert space-filling curve. Alternatively, one may use the coordinates of the objects' bounding boxes to represent each object by a four-dimensional point, and sort these points along a four-dimensional Hilbert-type curve. In experiments...

  11. Four-dimensional optical manipulation of colloidal particles

    DEFF Research Database (Denmark)

    Rodrigo, P.J.; Daria, V.R.; Glückstad, J.

    2005-01-01

    We transform a TEM00 laser mode into multiple counterpropagating optical traps to achieve four-dimensional simultaneous manipulation of multiple particles. Efficient synthesis and dynamic control of the counterpropagating-beam traps is carried out via the generalized phase contrast method...

  12. Four-dimensional conversion for spiritual leadership development: A ...

    African Journals Online (AJOL)

    The real challenge is how to develop such leadership. This article provides intentional and practical ways that may lead to the development of the needed leadership. Four-dimensional transformation of people can be planned and carried out both in the church arena and in the surrounding communities. Skills development ...

  13. Radiotherapy.

    Science.gov (United States)

    Krause, Sonja; Debus, Jürgen; Neuhof, Dirk

    2011-01-01

    Solitary plasmocytoma occurring in bone (solitary plasmocytoma of the bone, SBP) or in soft tissue (extramedullary plasmocytoma, EP) can be treated effectively and with little toxicity by local radiotherapy. Ten-year local control rates of up to 90% can be achieved. Patients with multiple myeloma often suffer from symptoms such as pain or neurological impairments that are amenable to palliative radiotherapy. In a palliative setting, short treatment schedules and lower radiation doses are used to reduce toxicity and duration of hospitalization. In future, low-dose total body irradiation (TBI) may play a role in a potentially curative regimen with nonmyeloablative conditioning followed by allogenic peripheral blood stem cell transplantation.

  14. Radiotherapy for Pertussis: An Historical Assessment

    Directory of Open Access Journals (Sweden)

    Edward J. Calabrese PhD

    2017-05-01

    Full Text Available X-ray therapy was used to treat pertussis/whooping cough during a 13-year period from 1923 to 1936 in North America and Europe. Twenty studies from clinicians in the United States reported that approximately 1500 cases of pertussis were treated by X-ray therapy usually with less than 0.5 erythema dose. Young children (<3 years comprised about 70% to 80% of the cases, with the age of cases ranging from as young as 1 month to 50 years. In general, symptoms of severe coughing, vomiting episodes, and spasms were significantly relieved in about 85% of cases following up to 3 treatments, while about 15% of the cases showed nearly full relief after only 1 treatment. The X-ray therapy was also associated with a marked reduction in mortality of young (<3 years children by over 90%. Despite such reported clinical success from a wide range of experienced researchers, the use of X-rays for the treatment of pertussis in young children was controversial, principally due to concerns of exposure to the thymus and thyroid even with the availability of lead shielding. By the mid-1930s, the treatment of pertussis cases via vaccine therapy came to dominate the therapeutic arena, and the brief era of a radiotherapy option for the treatment of pertussis ended.

  15. Manual control displays for a four-dimensional landing approach

    Science.gov (United States)

    Silverthorn, J. T.; Swaim, R. L.

    1975-01-01

    Six instrument rated pilots flew a STOL fixed base simulator to study the effectiveness of three displays for a four dimensional approach. The three examined displays were a digital readout of forward position error, a digital speed command, and an analog display showing forward position error and error prediction. A flight director was used in all conditions. All test runs were for a typical four dimensional approach in moderate turbulence that included a change in commanded ground speed, a change in flight path angle, and two standard rate sixty degree turns. Use of the digital forward position error display resulted in large overshoot in the forward position error. Some type of lead (rate or prediction information) was shown to be needed. The best overall performance was obtained using the speed command display. It was demonstrated that curved approaches can be flown with relative ease.

  16. (Compactified black branes in four dimensional f(R-gravity

    Directory of Open Access Journals (Sweden)

    N. Dimakis

    2018-02-01

    Full Text Available A new family of analytical solutions in a four dimensional static spacetime is presented for f(R-gravity. In contrast to General Relativity, we find that a non trivial black brane/string solution is supported in vacuum power law f(R-gravity for appropriate values of the parameters characterizing the model and when axisymmetry is introduced in the line element. For the aforementioned solution, we perform a brief investigation over its basic thermodynamic quantities.

  17. (Compactified) black branes in four dimensional f(R)-gravity

    Science.gov (United States)

    Dimakis, N.; Giacomini, Alex; Paliathanasis, Andronikos

    2018-02-01

    A new family of analytical solutions in a four dimensional static spacetime is presented for f (R) -gravity. In contrast to General Relativity, we find that a non trivial black brane/string solution is supported in vacuum power law f (R) -gravity for appropriate values of the parameters characterizing the model and when axisymmetry is introduced in the line element. For the aforementioned solution, we perform a brief investigation over its basic thermodynamic quantities.

  18. Automated four-dimensional Monte Carlo workflow using log files and real-time motion monitoring

    Science.gov (United States)

    Sibolt, P.; Cronholm, R. O.; Heath, E.; Andersen, C. E.; Behrens, C. F.

    2017-05-01

    With emerging techniques for tracking and gating methods in radiotherapy of lung cancer patients, there is an increasing need for efficient four-dimensional Monte Carlo (4DMC) based quality assurance (QA). An automated and flexible workflow for 4DMC QA, based on the 4DdefDOSXYZnrc user code, has been developed in python. The workflow has been tested and verified using an in-house developed dosimetry system comprised of a dynamic thorax phantom constructed for plastic scintillator dosimetry. The workflow is directly compatible with any treatment planning system and can also be triggered by the appearance of linac log files. It has minimum user interaction and, with the use of linac log files, it provides a method for verification of the actually delivered dose in the patient geometry.

  19. Dose and Position Measurements using a Novel Four-Dimensional In Vivo Dosimetry System

    Science.gov (United States)

    Cherpak, Amanda

    This work presents a comprehensive characterization of the dosimetric and position measurement characteristics as well as clinical implementation of a novel four-dimensional in vivo dosimetry system, RADPOS. Preliminary dose and position measurements were first conducted to evaluate any deviation from known characteristics of metal-oxide semiconductor field-effect transistors, MOSFETs, and electromagnetic positioning systems when they are used alone. The system was then combined with a deformable tissue equivalent lung phantom to simulate respiratory-induced tumour motion and lung deformation and to evaluate the potential use of the system as an effective quality assurance tool for 4D conformal radiotherapy. The final phase of testing involved using the RADPOS 4D in vivo dosimetry system in two different clinical trials. The first involved characterizing the breathing patterns of lung cancer patients throughout the course of treatment and measuring inter-fraction variations in skin dose. Within this framework, the feasibility of general use of the RADPOS system on patients during daily treatment fractions was also assessed. The second trial involved a modified RADPOS detector that contained a MOSFET array, allowing for dose measurements at five different points. This detector was used to measure dose and position in the prostatic urethra throughout seed implantation for transperineal interstitial permanent prostate brachytherapy. It has been found that the dosimetric response is similar to that of a microMOSFET, when used alone, aside from a slightly higher variation in angular response. Position measurements can be obtained with an uncertainty of +/- 2 mm when the detector remains within a specific optimal volume with respect to the magnetic field transmitter and when interfering metal objects are kept at least 200 mm away. Combining the RADPOS system with a deformable lung equivalent phantom allowed for efficient quality assurance of 4D radiation therapy, as

  20. Defining and assessing an anisotropic delineation margin for modern radiotherapy.

    Science.gov (United States)

    Bell, L R; Pogson, E M; Metcalfe, P E; Holloway, L C

    2016-12-01

    Uncertainty in target volume delineation for modern radiotherapy impacts dosimetry and patient outcomes. Delineation uncertainty is generally overlooked in practice as a source of error, potentially since historically, other uncertainties have been the main focus. This work defined and assessed an anisotropic delineation margin in both polar and spherical coordinate systems in order to account for the spatially varying nature of this uncertainty using a whole breast radiotherapy cohort as a proof of concept. A cohort of 21 whole breast radiotherapy patient datasets with clinical target volumes delineated by eight independent observers was utilized. Patients were divided into categories based on target volume and laterality. An anisotropic delineation margin for each category was determined by multiplying the average standard deviation in observer contours in each category by a factor of two. Standard deviation was determined in both polar and spherical coordinates at angular increments. This anisotropic approach was compared to a conventional clinical approach, where the delineation margin was applied in the cardinal directions only. The assessment of the delineation margin was undertaken by comparing the encompassment of the observer volumes by the target volume with added margin. The extra, presumed healthy tissue included in the margin and the malignant tissue missed by the margin were determined. The proposed delineation margin is effective at accounting for inter-observer variation, producing >95% coverage of all CTVs for polar, spherical, and Cartesian margins in 82%, 79%, and 92% of cases, respectively. Additionally, 1400 cm3 only with significantly greater encompassment of interobserver variation, less missed malignant tissue and less included healthy tissue. This methodology has been validated for a whole breast radiotherapy cohort as a proof of concept, however could be applied to other anatomical sites.

  1. Four-dimensional avatars of two-dimensional RCFT

    Energy Technology Data Exchange (ETDEWEB)

    Losev, A. [Institut Teoreticheskoj i Ehksperimental`noj Fiziki, Moscow (Russian Federation)]|[Yale Univ., New Haven, CT (United States). Dept. of Physics; Moore, G. [Yale Univ., New Haven, CT (United States). Dept. of Physics; Nekrasov, N. [Institut Teoreticheskoj i Ehksperimental`noj Fiziki, Moscow (Russian Federation)]|[Princeton Univ., NJ (United States). Dept. of Physics; Shatashvili, S. [Yale Univ., New Haven, CT (United States). Dept. of Physics

    1996-03-01

    We investigate a 4D analog of 2D WZW theory. The theory turns out to have surprising finiteness properties and an infinite-dimensional current algebra symmetry. Some correlation functions are determined by this symmetry. One way to define the theory systematically proceeds by the quantization of moduli spaces of holomorphic vector bundles over algebraic surfaces. We outline how one can define vertex operators in the theories. Finally, we define four-dimensional ``conformal blocks`` and present an analog of the Verlinde formula. (orig.).

  2. Concurrent Boost with Adjuvant Breast Hypofractionated Radiotherapy and Toxicity Assessment

    Directory of Open Access Journals (Sweden)

    Mona M. Sayed

    2015-01-01

    Full Text Available Background: The use of shorter radiotherapy schedules has an economic and logistic advantage for radiotherapy departments, as well as a high degree of patient convenience. The aim of this study is to assess the acute and short-term late toxicities of a hypofractionated radiotherapy schedule with a concomitant boost. Methods: We enrolled 57 eligible patients as group A. These patients received 42.5 Gy in 16 fractions of 2.66 Gy each to the whole breast over 3.2 weeks. A concomitant electron boost of 12 Gy in 16 fractions was also administered which gave an additional 0.75 Gy daily to the lumpectomy area for a total radiation dose of 54.5 Gy. Toxicity was recorded at three weeks and at three months for this group as well as for a control group (group B. The control group comprised 76 eligible patients treated conventionally with 50 Gy to the whole breast over five weeks followed by a sequential electron boost of 12 Gy in 2 Gy per fraction. Results: There were no statistically significant differences observed in the incidence of acute skin toxicity, breast pain, and edema recorded at three weeks or pigmentation and fibrosis recorded at three months between the two groups (P0.05. Conclusion: The results of this study suggest there are no increased acute and shortterm late toxicities affiliated with the hypofractionated schedule plus a concomitant boost as prescribed compared to the conventional fractionation of adjuvant breast radiotherapy. Large randomized trials and long-term follow-up are needed to confirm these favorable findings.

  3. Four-dimensional black holes in Einsteinian cubic gravity

    Science.gov (United States)

    Bueno, Pablo; Cano, Pablo A.

    2016-12-01

    We construct static and spherically symmetric generalizations of the Schwarzschild- and Reissner-Nordström-(anti-)de Sitter [RN-(A)dS] black-hole solutions in four-dimensional Einsteinian cubic gravity (ECG). The solutions are characterized by a single function which satisfies a nonlinear second-order differential equation. Interestingly, we are able to compute independently the Hawking temperature T , the Wald entropy S and the Abbott-Deser mass M of the solutions analytically as functions of the horizon radius and the ECG coupling constant λ . Using these we show that the first law of black-hole mechanics is exactly satisfied. Some of the solutions have positive specific heat, which makes them thermodynamically stable, even in the uncharged and asymptotically flat case. Further, we claim that, up to cubic order in curvature, ECG is the most general four-dimensional theory of gravity which allows for nontrivial generalizations of Schwarzschild- and RN-(A)dS characterized by a single function which reduce to the usual Einstein gravity solutions when the corresponding higher-order couplings are set to zero.

  4. Low-energy structure of four-dimensional superstrings

    Energy Technology Data Exchange (ETDEWEB)

    Zwirner, F.

    1988-05-01

    The N = 1, d = 4 supergravity theories derived as the low-energy limit of four-dimensional superstrings are discussed, focusing on the properties of their effective potentials. Gauge symmetry breaking is possible along several flat directions. A class of superpotential modifications is introduced, which describes supersymmetry breaking with vanishing cosmological constant and Str M{sup 2} = 0 at any minimum of the tree level potential. Under more restrictive assumptions, there are minima with broken supersymmetry at which also Str f(M{sup 2}) = 0 for any function f, so that the whole one-loop cosmological constant vanishes. This result is interpreted in terms of a new discrete boson-fermion symmetry, relating particles whose helicities differ by 3/2, e.g., the graviton and the dilatino.' 21 refs.

  5. Determining intrafractional prostate motion using four dimensional ultrasound system

    DEFF Research Database (Denmark)

    Baker, Mariwan; Behrens, Claus F.

    2016-01-01

    Background: In prostate radiotherapy, it is essential that the prostate position is within the planned volume during the treatment delivery. The aim of this study is to investigate whether intrafractional motion of the prostate is of clinical consequence, using a novel 4D autoscan ultrasound prob...

  6. Toward four-dimensional image-guided adaptive brachytherapy in locally recurrent endometrial cancer.

    Science.gov (United States)

    Fokdal, Lars; Ørtoft, Gitte; Hansen, Estrid S; Røhl, Lisbeth; Pedersen, Erik Morre; Tanderup, Kari; Lindegaard, Jacob Christian

    2014-01-01

    To evaluate clinical outcome and feasibility of a four-dimensional image-guided adaptive brachytherapy concept in patients with locally recurrent endometrial cancer. Forty-three patients with locally recurrent endometrial cancer were included. Treatment consisted of conformal external beam radiotherapy followed by a boost using pulsed-dose-rate brachytherapy (BT). Large tumors were treated with MRI-guided interstitial BT. Small tumors were treated with CT-guided intracavitary BT. The planning aim (total external beam radiotherapy and BT) for high-risk clinical target volume was D90 > 80 Gy, whereas constraints for organs at risk were D2cc ≤ 90 Gy for bladder and D2cc ≤ 70 Gy for rectum, sigmoid, and bowel in terms of equivalent dose in 2 Gy fractions. Median high-risk clinical target volume was 18 cm(3) (range, 0-91). D90 was 82 Gy (range, 77-88). D2cc to bladder, rectum, and sigmoid were 67 Gy (range, 50-81), 67 Gy (range, 51-77), and 55 Gy (range, 44-68), respectively. Median followup was 30 months (6-88). Two-year local control rate was 92% (standard error [SE], 5). Disease-free survival rate and overall survival rate was 59% (SE, 8) and 78% (SE, 7), respectively. Patients with low- to intermediate-risk for recurrence had a 2-year disease-free survival rate of 72% (SE, 9) compared with 42% (SE, 12) in patients with high risk for recurrence (p = 0.04). Late morbidity Grade 3 was recorded in 5 (12%) patients. Four-dimensional image-guided adaptive brachytherapy is feasible in locally recurrent endometrial cancer. Local control rate is good. Systemic control remains a problem in patients with high risk for recurrence. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  7. Four-dimensional unsubtraction from the loop-tree duality

    Energy Technology Data Exchange (ETDEWEB)

    Sborlini, Germán F.R. [Instituto de Física Corpuscular,Universitat de València - Consejo Superior de Investigaciones Científicas,Parc Científic, E-46980 Paterna, Valencia (Spain); Departamento de Física and IFIBA, FCEyN, Universidad de Buenos Aires (1428) Pabellón 1 Ciudad Universitaria, Capital Federal (Argentina); Driencourt-Mangin, Félix [Instituto de Física Corpuscular,Universitat de València - Consejo Superior de Investigaciones Científicas,Parc Científic, E-46980 Paterna, Valencia (Spain); Hernández-Pinto, Roger J. [Instituto de Física Corpuscular,Universitat de València - Consejo Superior de Investigaciones Científicas,Parc Científic, E-46980 Paterna, Valencia (Spain); Facultad de Ciencias Físico-Matemáticas, Universidad Autónoma de Sinaloa, Ciudad Universitaria, CP 80000, Culiacán, Sinaloa (Mexico); Rodrigo, Germán [Instituto de Física Corpuscular,Universitat de València - Consejo Superior de Investigaciones Científicas,Parc Científic, E-46980 Paterna, Valencia (Spain)

    2016-08-29

    We present a new algorithm to construct a purely four dimensional representation of higher-order perturbative corrections to physical cross-sections at next-to-leading order (NLO). The algorithm is based on the loop-tree duality (LTD), and it is implemented by introducing a suitable mapping between the external and loop momenta of the virtual scattering amplitudes, and the external momenta of the real emission corrections. In this way, the sum over degenerate infrared states is performed at integrand level and the cancellation of infrared divergences occurs locally without introducing subtraction counter-terms to deal with soft and final-state collinear singularities. The dual representation of ultraviolet counter-terms is also discussed in detail, in particular for self-energy contributions. The method is first illustrated with the scalar three-point function, before proceeding with the calculation of the physical cross-section for γ{sup ∗}→qq̄(g), and its generalisation to multi-leg processes. The extension to next-to-next-to-leading order (NNLO) is briefly commented.

  8. Four-dimensional positron age-momentum correlation

    Science.gov (United States)

    Ackermann, Ulrich; Löwe, Benjamin; Dickmann, Marcel; Mitteneder, Johannes; Sperr, Peter; Egger, Werner; Reiner, Markus; Dollinger, Günther

    2016-11-01

    We have performed first four-dimensional age-momentum correlation (4D-AMOC) measurements at a pulsed high intensity positron micro beam and determined the absolute value of the three-dimensional momentum of the electrons annihilating with the positrons in coincidence with the positron age in the sample material. We operated two position sensitive detectors in coincidence to measure the annihilation radiation: a pixelated HPGe-detector and a microchannel plate image intensifier with a CeBr3 scintillator pixel array. The transversal momentum resolution of the 4D-AMOC setup was measured to be about 17 × 10-3 {m}0c (FWHM) and was circa 3.5 times larger than the longitudinal momentum resolution. The total time resolution was 540 ps (FWHM). We measured two samples: a gold foil and a carbon tape at a positron implantation energy of 2 keV. For each sample discrete electron momentum states and their respective positron lifetimes were extracted.

  9. Four dimensional variational inversion of atmospheric chemical sources in WRFDA

    Science.gov (United States)

    Guerrette, J. J.

    Atmospheric aerosols are known to affect health, weather, and climate, but their impacts on regional scales are uncertain due to heterogeneous source, transport, and transformation mechanisms. The Weather Research and Forecasting model with chemistry (WRF-Chem) can account for aerosol-meteorology feedbacks as it simultaneously integrates equations of dynamical and chemical processes. Here we develop and apply incremental four dimensional variational (4D-Var) data assimilation (DA) capabilities in WRF-Chem to constrain chemical emissions (WRFDA-Chem). We develop adjoint (ADM) and tangent linear (TLM) model descriptions of boundary layer mixing, emission, aging, dry deposition, and advection of black carbon (BC) aerosol. ADM and TLM model performance is verified against finite difference derivative approximations. A second order checkpointing scheme is used to reduce memory costs and enable simulations longer than six hours. We apply WRFDA-Chem to constraining anthropogenic and biomass burning sources of BC throughout California during the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Manual corrections to the prior emissions and subsequent inverse modeling reduce the spread in total emitted BC mass between two biomass burning inventories from a factor of x10 to only x2 across three days of measurements. We quantify posterior emission variance using an eigendecomposition of the cost function Hessian matrix. We also address the limited scalability of 4D-Var, which traditionally uses a sequential optimization algorithm (e.g., conjugate gradient) to approximate these Hessian eigenmodes. The Randomized Incremental Optimal Technique (RIOT) uses an ensemble of TLM and ADM instances to perform a Hessian singular value decomposition. While RIOT requires more ensemble members than Lanczos requires iterations to converge to a comparable posterior control vector, the wall-time of RIOT is x10 shorter since the

  10. Improving left ventricular segmentation in four-dimensional flow MRI using intramodality image registration for cardiac blood flow analysis.

    Science.gov (United States)

    Gupta, Vikas; Bustamante, Mariana; Fredriksson, Alexandru; Carlhäll, Carl-Johan; Ebbers, Tino

    2018-01-01

    Assessment of blood flow in the left ventricle using four-dimensional flow MRI requires accurate left ventricle segmentation that is often hampered by the low contrast between blood and the myocardium. The purpose of this work is to improve left-ventricular segmentation in four-dimensional flow MRI for reliable blood flow analysis. The left ventricle segmentations are first obtained using morphological cine-MRI with better in-plane resolution and contrast, and then aligned to four-dimensional flow MRI data. This alignment is, however, not trivial due to inter-slice misalignment errors caused by patient motion and respiratory drift during breath-hold based cine-MRI acquisition. A robust image registration based framework is proposed to mitigate such errors automatically. Data from 20 subjects, including healthy volunteers and patients, was used to evaluate its geometric accuracy and impact on blood flow analysis. High spatial correspondence was observed between manually and automatically aligned segmentations, and the improvements in alignment compared to uncorrected segmentations were significant (P flow analysis from manual and automatically corrected segmentations did not differ significantly (P > 0.05). Our results demonstrate the efficacy of the proposed approach in improving left-ventricular segmentation in four-dimensional flow MRI, and its potential for reliable blood flow analysis. Magn Reson Med 79:554-560, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  11. Implementation of a risk assessment tool based on a probabilistic safety assessment developed for radiotherapy practices

    Energy Technology Data Exchange (ETDEWEB)

    Paz, A.; Godinez, V.; Lopez, R., E-mail: abpaz@cnsns.gob.m [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Barragan No. 779, Col. Narvarte, 03020 Mexico D. F. (Mexico)

    2010-10-15

    The present work describes the implementation process and main results of the risk assessment to the radiotherapy practices with Linear Accelerators (Linac), with cobalt 60, and with brachytherapy. These evaluations were made throughout the risk assessment tool for radiotherapy practices SEVRRA (risk evaluation system for radiotherapy), developed at the Mexican National Commission in Nuclear Safety and Safeguards derived from the outcome obtained with the Probabilistic Safety Analysis developed at the Ibero-American Regulators Forum for these radiotherapy facilities. The methodology used is supported by risk matrices method, a mathematical tool that estimates the risk to the patient, radiation workers and public from mechanical failures, mis calibration of the devices, human mistakes, and so. The initiating events are defined as those undesirable events that, together with other failures, can produce a delivery of an over-dose or an under-dose of the medical prescribed dose, to the planned target volume, or a significant dose to non prescribed human organs. Initiating events frequency and reducer of its frequency (actions intended to avoid the accident) are estimated as well as robustness of barriers to those actions, such as mechanical switches, which detect and prevent the accident from occurring. The spectrum of the consequences is parameterized, and the actions performed to reduce the consequences are identified. Based on this analysis, a software tool was developed in order to simplify the evaluations to radiotherapy installations and it has been applied as a first step forward to some Mexican installations, as part of a national implementation process, the final goal is evaluation of all Mexican facilities in the near future. The main target and benefits of the SEVRRA implementation are presented in this paper. (Author)

  12. Sonographic Assessment of Parotid and Submandibular Glands in Patients Undergoing 3D Conformal Radiotherapy

    Directory of Open Access Journals (Sweden)

    Johari M

    2016-06-01

    Full Text Available The aim of this study was to evaluate sonographic changes in parotid and submandibular salivary glands in patients undergoing radiotherapy for head and neck malignancies. In addition, salivary changes subsequent to radiotherapy were evaluated objectively and subjectively. Twenty patients(13males and 7females with head and neck malignancies, who had been referred to the Radiotherapy/Oncology Department of the Shahid Madani Hospital in Tabriz, Iran, were included in the study. Length, width, echotexture, echogenicity and margins of parotid and submandibular glands were evaluated before and after radiotherapy using sonography. Peak-systolic velocity(PSV,end-diastolic velocity(EDV and resistive index(RI were also assessed by Doppler sonography. Xerostomia subsequent to radiotherapy was evaluated with the use of two techniques: patients’ self-reported scoring and objective measurement of resting saliva. There was a significant decrease in the width of the parotid gland after radiotherapy compared to baseline(P=0.005.Although the length of the parotid gland and the dimensions of submandibular gland decrease, the differences were not significant. In addition, the echogenicity, echotexture and the margin of the glands change to hypoechoic, heterogenic and irregular, respectively, subsequent to radiotherapy. The Doppler technique showed decrease in PSV and RI and an increase in EDV; however, only the decrease in RI in the submandibular gland was statistically significant(P=0.002.The results showed a significant decrease in salivary flow after radiotherapy(P<0.001.In addition, based on the patients reports, the severity of xerostomia increased significantly after radiotherapy(P<0.001. Songraphic changes of parotid and submandibular glands after radiotherapy should be considered in ultrasound examinations. The damages to the parotid and submandibular glands had significant influence in patient post 3D-CRT.

  13. Patient-specific modelling of whole heart anatomy, dynamics and haemodynamics from four-dimensional cardiac CT images

    OpenAIRE

    Mihalef, Viorel; Ionasec, Razvan Ioan; Sharma, Puneet; Georgescu, Bogdan; Voigt, Ingmar; Suehling, Michael; Comaniciu, Dorin

    2011-01-01

    There is a growing need for patient-specific and holistic modelling of the heart to support comprehensive disease assessment and intervention planning as well as prediction of therapeutic outcomes. We propose a patient-specific model of the whole human heart, which integrates morphology, dynamics and haemodynamic parameters at the organ level. The modelled cardiac structures are robustly estimated from four-dimensional cardiac computed tomography (CT), including all four chambers and valves a...

  14. Preventing Data Ambiguity in Infectious Diseases with Four-Dimensional and Personalized Evaluations.

    Directory of Open Access Journals (Sweden)

    Michelle J Iandiorio

    Full Text Available Diagnostic errors can occur, in infectious diseases, when anti-microbial immune responses involve several temporal scales. When responses span from nanosecond to week and larger temporal scales, any pre-selected temporal scale is likely to miss some (faster or slower responses. Hoping to prevent diagnostic errors, a pilot study was conducted to evaluate a four-dimensional (4D method that captures the complexity and dynamics of infectious diseases.Leukocyte-microbial-temporal data were explored in canine and human (bacterial and/or viral infections, with: (i a non-structured approach, which measures leukocytes or microbes in isolation; and (ii a structured method that assesses numerous combinations of interacting variables. Four alternatives of the structured method were tested: (i a noise-reduction oriented version, which generates a single (one data point-wide line of observations; (ii a version that measures complex, three-dimensional (3D data interactions; (iii a non-numerical version that displays temporal data directionality (arrows that connect pairs of consecutive observations; and (iv a full 4D (single line-, complexity-, directionality-based version.In all studies, the non-structured approach revealed non-interpretable (ambiguous data: observations numerically similar expressed different biological conditions, such as recovery and lack of recovery from infections. Ambiguity was also found when the data were structured as single lines. In contrast, two or more data subsets were distinguished and ambiguity was avoided when the data were structured as complex, 3D, single lines and, in addition, temporal data directionality was determined. The 4D method detected, even within one day, changes in immune profiles that occurred after antibiotics were prescribed.Infectious disease data may be ambiguous. Four-dimensional methods may prevent ambiguity, providing earlier, in vivo, dynamic, complex, and personalized information that facilitates both

  15. Gross tumor volume dependency on phase sorting methods of four-dimensional computed tomography images for lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Yong; Lim, Sang Wook; Ma, Sun Young; Yu, Je Sang [Dept. of Radiation Oncology, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan (Korea, Republic of)

    2017-09-15

    To see the gross tumor volume (GTV) dependency according to the phase selection and reconstruction methods, we measured and analyzed the changes of tumor volume and motion at each phase in 20 cases with lung cancer patients who underwent image-guided radiotherapy. We retrospectively analyzed four-dimensional computed tomography (4D-CT) images in 20 cases of 19 patients who underwent image-guided radiotherapy. The 4D-CT images were reconstructed by the maximum intensity projection (MIP) and the minimum intensity projection (Min-IP) method after sorting phase as 40%–60%, 30%–70%, and 0%–90%. We analyzed the relationship between the range of motion and the change of GTV according to the reconstruction method. The motion ranges of GTVs are statistically significant only for the tumor motion in craniocaudal direction. The discrepancies of GTV volume and motion between MIP and Min-IP increased rapidly as the wider ranges of duty cycles are selected. As narrow as possible duty cycle such as 40%–60% and MIP reconstruction was suitable for lung cancer if the respiration was stable. Selecting the reconstruction methods and duty cycle is important for small size and for large motion range tumors.

  16. Improving the Horizontal Transport in the Lower Troposphere with Four Dimensional Data Assimilation

    Science.gov (United States)

    The physical processes involved in air quality modeling are governed by dynamically-generated meteorological model fields. This research focuses on reducing the uncertainty in the horizontal transport in the lower troposphere by improving the four dimensional data assimilation (F...

  17. Balancing Equity and Advancement: The Role of Health Technology Assessment in Radiotherapy Resource Allocation.

    Science.gov (United States)

    Rodin, D; Aggarwal, A; Lievens, Y; Sullivan, R

    2017-02-01

    Radiotherapy is an essential modality for effective cancer control, yet enormous inequalities in access in low- and middle-income countries (LMICs) have created one of the largest global technology gaps in medicine today. The Global Task Force on Radiotherapy for Cancer Control quantified this gap and showed that over half of patients worldwide do not have access to treatment. Governments, policy makers and the global health community have ignored this crisis due to the complexity of radiotherapy technology and its seemingly high upfront costs. However, understanding the cost of treatment in the context of a dramatic clinical benefit could help to demonstrate the feasibility of radiotherapy in diverse income settings. When there are scarce resources, such analysis is essential in order to set priorities and provide high-value interventions to large populations. Here we explore the current status of economic evaluation tools in LMICs and some of the barriers to their use. We describe how the concepts of health technology assessment, value-based care and investment frameworks can be applied to the global crisis of radiotherapy availability to guide appropriate capacity building and resource utilisation. The development of local expertise in these health economic tools can be a powerful level to improve cancer care in LMICs and to build universal global access to radiotherapy. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  18. Ultra high speed optical transmission using subcarrier-multiplexed four-dimensional LDPC-coded modulation.

    Science.gov (United States)

    Batshon, Hussam G; Djordjevic, Ivan; Schmidt, Ted

    2010-09-13

    We propose a subcarrier-multiplexed four-dimensional LDPC bit-interleaved coded modulation scheme that is capable of achieving beyond 480 Gb/s single-channel transmission rate over optical channels. Subcarrier-multiplexed four-dimensional LDPC coded modulation scheme outperforms the corresponding dual polarization schemes by up to 4.6 dB in OSNR at BER 10(-8).

  19. Preoperative vascular mapping for facial allotransplantation: four-dimensional computed tomographic angiography versus magnetic resonance angiography.

    Science.gov (United States)

    Soga, Shigeyoshi; Pomahac, Bohdan; Mitsouras, Dimitrios; Kumamaru, Kanako; Powers, Sara L; Prior, Richard F; Signorelli, Jason; Bueno, Ericka M; Steigner, Michael L; Rybicki, Frank J

    2011-10-01

    Facial allotransplantation requires a detailed arterial and venous assessment for surgical planning. Target vessels are often depleted by multiple reconstructive attempts or the severe facial injury itself. The purpose of this study was to retrospectively compare the diagnostic performance of computed tomography and magnetic resonance angiography in the preoperative assessment. Four-dimensional (three spatial planes plus time) computed tomographic and magnetic resonance images including 126 potential vessels (76 arteries and 50 veins) from five candidates were analyzed independently by two radiologists using a four-point image quality scale. Computed tomographic versus magnetic resonance image quality was compared directly, using a computed tomographic angiography consensus read as reference standard. Vessels with metal artifact on magnetic resonance imaging, computed tomography, or both underwent separate analyses to determine the impact of metal implants on image quality. Considering all 126 vessels, the mean computed tomographic image quality was superior to that of magnetic resonance angiography. When considering individual vessels, all except for major neck vessels were better visualized by computed tomography. Images of 26 vessels were degraded by metal artifact; magnetic resonance image quality was inferior for those vessels. Considering images of major vessels with no metal artifact, there was no significant mean image quality difference between computed tomography and magnetic resonance imaging. Computed tomographic angiography should be used as the first-choice modality for preoperative imaging of facial transplant patients because, when compared with magnetic resonance imaging, the visualization of small vessels is far superior and images have fewer artifacts. Diagnostic, II.

  20. Assessment of radiotherapy for squamous cell carcinoma of the lip

    Energy Technology Data Exchange (ETDEWEB)

    Oota, Sayako; Yoshimura, Ryo-ichi; Miura, Masahiko; Shibuya, Hitoshi [Tokyo Medical and Dental Univ. (Japan). Hospital

    2001-03-01

    Lip cancer is rare malignancy in Japan. We reviewed the results of 18 patients (19 lesions) with SCC who were treated with radiotherapy. The stages were T1 in 8, T2 in 7, T3 in 3 and T4 in 1 case. One patient had lymph node metastasis. The relapse-free survival of patients with stage I/II lesions at 3 and 5 years was 92.3% and 92.3%. One patient died of local control failure. Three patients developed regional lymph node metastases, and were cured by neck dissection, following electron beam therapy in one case. (author)

  1. Normal standards for fetal neurobehavioral developments--longitudinal quantification by four-dimensional sonography.

    Science.gov (United States)

    Kurjak, Asim; Andonotopo, Wiku; Hafner, Tomislav; Salihagic Kadic, Aida; Stanojevic, Milan; Azumendi, Guillermo; Ahmed, Badreldeen; Carrera, Jose M; Troyano, J M

    2006-01-01

    To construct normal standards for fetal neurobehavioral development using longitudinal observations through all trimesters by four-dimensional sonography. A group of 100 healthy normal singleton pregnancies were recruited for longitudinal 4D US examinations to evaluate fetal neurodevelopmental parameters between 7 to 40 weeks' gestation. Variables of maternal and fetal characteristics including gestational age, eight fetal movements patterns in the first trimester and 14 parameters of fetal movement and fetal facial expression patterns recorded thereafter for the construction of fetal neurological charts. Measurement of 7 parameters in the first trimester and 11 parameters in the second and third trimesters correlated with gestational age (P<0.05). Those parameters have been followed longitudinally through all trimesters and showed increasing frequency of fetal movements during the first trimester. A tendency towards decreased frequency of facial expressions and movement patterns with increasing gestational age from second to third trimesters has been noticed. With 4D sonography, it is possible to quantitatively assess normal neurobehavioral development. There is urgent need for further multicentric studies until a sufficient degree of normative data is available and the predictive validity of the specific relationship between fetal neurobehavior and child developmental outcome is better established.

  2. A technique for quantifying wrist motion using four-dimensional computed tomography: approach and validation.

    Science.gov (United States)

    Zhao, Kristin; Breighner, Ryan; Holmes, David; Leng, Shuai; McCollough, Cynthia; An, Kai-Nan

    2015-07-01

    Accurate quantification of subtle wrist motion changes resulting from ligament injuries is crucial for diagnosis and prescription of the most effective interventions for preventing progression to osteoarthritis. Current imaging techniques are unable to detect injuries reliably and are static in nature, thereby capturing bone position information rather than motion which is indicative of ligament injury. A recently developed technique, 4D (three dimensions + time) computed tomography (CT) enables three-dimensional volume sequences to be obtained during wrist motion. The next step in successful clinical implementation of the tool is quantification and validation of imaging biomarkers obtained from the four-dimensional computed tomography (4DCT) image sequences. Measures of bone motion and joint proximities are obtained by: segmenting bone volumes in each frame of the dynamic sequence, registering their positions relative to a known static posture, and generating surface polygonal meshes from which minimum distance (proximity) measures can be quantified. Method accuracy was assessed during in vitro simulated wrist movement by comparing a fiducial bead-based determination of bone orientation to a bone-based approach. The reported errors for the 4DCT technique were: 0.00-0.68 deg in rotation; 0.02-0.30 mm in translation. Results are on the order of the reported accuracy of other image-based kinematic techniques.

  3. Four-dimensional microscope- integrated optical coherence tomography to enhance visualization in glaucoma surgeries.

    Science.gov (United States)

    Pasricha, Neel Dave; Bhullar, Paramjit Kaur; Shieh, Christine; Viehland, Christian; Carrasco-Zevallos, Oscar Mijail; Keller, Brenton; Izatt, Joseph Adam; Toth, Cynthia Ann; Challa, Pratap; Kuo, Anthony Nanlin

    2017-01-01

    We report the first use of swept-source microscope-integrated optical coherence tomography (SS-MIOCT) capable of live four-dimensional (4D) (three-dimensional across time) imaging intraoperatively to directly visualize tube shunt placement and trabeculectomy surgeries in two patients with severe open-angle glaucoma and elevated intraocular pressure (IOP) that was not adequately managed by medical intervention or prior surgery. We performed tube shunt placement and trabeculectomy surgery and used SS-MIOCT to visualize and record surgical steps that benefitted from the enhanced visualization. In the case of tube shunt placement, SS-MIOCT successfully visualized the scleral tunneling, tube shunt positioning in the anterior chamber, and tube shunt suturing. For the trabeculectomy, SS-MIOCT successfully visualized the scleral flap creation, sclerotomy, and iridectomy. Postoperatively, both patients did well, with IOPs decreasing to the target goal. We found the benefit of SS-MIOCT was greatest in surgical steps requiring depth-based assessments. This technology has the potential to improve clinical outcomes.

  4. Fractionated brain stereotactic radiotherapy: assessment of repositioning precision using a thermoforming mask; Radiotherapie stereotaxique cerebrale fractionnee: evaluation de la precision du repositionnement en utilisant un masque thermoformable

    Energy Technology Data Exchange (ETDEWEB)

    Barret, A.; Champeaux-Orange, E.; Bouscayrol, H.; Wachter, T. [CHR La Source, Orleans (France)

    2011-10-15

    The authors report a study which aimed at assessing the patient repositioning precision obtained with a support system used during a brain fractionated stereotactic radiotherapy and comprising a thermoforming mask (Elektra head mask). The repositioning is assessed by means of scano-graphies and superimposition with the stereotactic frame. A three-dimensional vector has been computed for each patient. The average displacement corresponds to that published in literature. The high quality of the support system allows a non invasive brain stereotactic radiotherapy to be performed which is also comfortable for the patient. Short communication

  5. Four-dimensional gravitational backgrounds based on N = 4, $\\widehat{c}$ = 4, superconformal systems

    CERN Document Server

    Kounnas, Costas

    1994-01-01

    We propose two new realizations of the N=4, $\\hat{c}=4$ superconformal system based on the compact and non-compact versions of parafermionic algebras. The target space interpretation of these systems is given in terms of four-dimensional target spaces with non-trivial metric and topology different from the previously known four-dimensional semi-wormhole realization. The proposed $\\hat{c}=4$ systems can be used as a building block to construct perturbatively stable superstring solutions with covariantized target space supersymmetry around non-trivial gravitational and dilaton backgrounds.

  6. The Quality of Curative-intent Radiotherapy for Non-small Cell Lung Cancer in the UK.

    Science.gov (United States)

    McAleese, J; Baluch, S; Drinkwater, K

    2015-09-01

    Lung cancer is the leading cause of cancer-related death in the UK. The quality of curative-intent radiotherapy is associated with better outcomes. National quality standards from the National Institute for Health and Care Excellence (NICE) on patient work-up and treatment selection were used, with guidance from the Royal College of Radiologists on the technical delivery of radiotherapy, to assess the quality of curative-intent non-small cell lung cancer radiotherapy and to describe current UK practice. Radiotherapy departments completed one questionnaire for each patient started on curative-intent radiotherapy for 8 weeks in 2013. Eighty-two per cent of centres returned a total of 317 proformas. Patient selection with positron emission tomography/computed tomography, performance status and Forced Expiratory Volume in 1 second (FEV1) was usually undertaken. Fifty-six per cent had pathological confirmation of mediastinal lymph nodes and 22% staging brain scans; 20% were treated with concurrent chemoradiation, 12% with Stereotactic Ablative Radiotherapy (SABR) and 8% with Continuous Hyperfractionated Accelerated Radiotherapy (CHART). Sixty-three per cent of patients received 55 Gy/20 fractions. Although respiratory compensation was routinely undertaken, only 33% used four-dimensional computed tomography. Seventy per cent of patients were verified with cone beam computed tomography. There was consistency of practice in dosimetric constraints for organs at risk and follow-up. This audit has described current UK practice. The latest recommendations for patient selection with pathological confirmation of mediastinal lymph nodes, brain staging and respiratory function testing are not universally followed. Although there is evidence of increasing use of newer techniques such as four-dimensional computed tomography and cone beam image-guided radiotherapy, there is still variability in access. Efforts should be made to improve access to modern technologies and quality

  7. Representations of the rotation reflection symmetry group of the four-dimensional cubic lattice

    Science.gov (United States)

    Mandula, Jeffrey E.; Zweig, George; Govaerts, Jan

    1983-11-01

    The structure and representations of the rotation reflection symmetry group of the four-dimensional cubic lattice are described. Their connections with the representations of the three-dimensional lattice rotation reflection group, and with the representations of the continuous O(3) and O(4) groups are given.

  8. Representations of the rotation reflection symmetry group of the four-dimensional cubic lattice

    Energy Technology Data Exchange (ETDEWEB)

    Mandula, J.E. (Washington Univ., St. Louis, MO (USA). Dept. of Physics); Zweig, G. (Los Alamos National Lab., NM (USA)); Govaerts, J. (Louvain Univ. (Belgium). Inst. for Theoretical Physics)

    1983-11-15

    The structure and representations of the rotation reflection symmetry group of the four-dimensional cubic lattice are described. Their connections with the representations of the three-dimensional lattice rotation reflection group, and with the representations of the continuous O(3) and O(4) groups are given.

  9. Double-valued representations of the four-dimensional cubic lattice rotation group

    Energy Technology Data Exchange (ETDEWEB)

    Mandula, J.E.; Shpiz, E. (Washington Univ., St. Louis, MO (USA). Dept. of Physics)

    1984-01-23

    The double-valued representations of the rotation symmetry group of the four-dimensional cubic lattice are described. Their connections with double-valued representations of the three-dimensional cubic lattice rotation group and of the continuous O(3) and O(4) groups are given in detail.

  10. Double-valued representations of the four-dimensional cubic lattice rotation group

    Science.gov (United States)

    Mandula, Jeffrey E.; Shpiz, Edward

    1984-01-01

    The double-valued representations of the rotation symmetry group of the four-dimensional cubic lattice are described. Their connections with double-valued representations of the three-dimensional cubic lattice rotation group and of the continuous O(3) and O(4) groups are given in detail.

  11. The solution to Slavnov--Taylor identities in a general four dimensional supersymmetric theory

    OpenAIRE

    Kondrashuk, Igor

    2001-01-01

    A solution to Slavnov-Taylor identities in a general four dimensional N=1 supersymmetric Yang-Mills theory containing arbitrary matter superfields is proposed. The solution proposed appears just a simple generalization of an analogous solution in the pure supersymmetric Yang-Mills theory.

  12. Adding Four- Dimensional Data Assimilation (a.k.a. grid nudging) to MPAS

    Science.gov (United States)

    Adding four-dimensional data assimilation (a.k.a. grid nudging) to MPAS.The U.S. Environmental Protection Agency is investigating the use of MPAS as the meteorological driver for its next-generation air quality model. To function as such, MPAS needs to operate in a diagnostic mod...

  13. Four-dimensional Osserman-Ivanov-Petrova metrics of neutral signature

    Energy Technology Data Exchange (ETDEWEB)

    Calvino-Louzao, Esteban; GarcIa-RIo, Eduardo; Vazquez-Lorenzo, Ramon [Department of Geometry and Topology, Faculty of Mathematics, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain)

    2007-05-07

    Algebraic curvature tensors which are Osserman-IP in the (- - + +)-signature setting are completely determined. As a consequence, it is shown that a four-dimensional pointwise Osserman-IP manifold is a space of constant sectional curvature or, otherwise, at each point the Jacobi operators either vanish or they are two-step nilpotent.

  14. Registration-based Reconstruction of Four-dimensional Cone Beam Computed Tomography

    DEFF Research Database (Denmark)

    Christoffersen, Christian; Hansen, David Christoffer; Poulsen, Per Rugaard

    2013-01-01

    We present a new method for reconstruction of four-dimensional (4D) cone beam computed tomography from an undersampled set of X-ray projections. The novelty of the proposed method lies in utilizing optical flow based registration to facilitate that each temporal phase is reconstructed from the full...

  15. Four dimensional data assimilation of dual doppler lidar observations of the urban boundary layer

    Science.gov (United States)

    Xia, Quanxin

    A better understanding of transport processes in the atmospheric boundary layer (ABL) is essential for emergency action in cases of chemical and biological agent dispersion. However, our current knowledge of ABL processes is limited, due in large part to frequently changing large-scale forcings and the lack of measurements of nearly any atmospheric variable at higher altitudes. To gain new insights into the ABL transport processes and the dispersion of contaminants in cities to address some concerns of homeland security, an atmospheric dispersion study was held in Oklahoma City, Oklahoma in 2003. Two Doppler Light-Detection-And-Ranging (lidar) systems were deployed to collect hours of radial velocity and aerosol concentration data in both the daytime and nighttime boundary layers. These lidar data permit the study of ABL flow characteristics and the atmospheric dispersion of particles in an urban setting. The four dimensional variational data assimilation method (4DVAR) is adopted to merge limited lidar observations with a computational fluid dynamics model to derive detailed three-dimensional (3D) wind and temperature data. The accuracy of the 4DVAR method is assessed by comparing the single lidar retrieval with both the second lidar measurement and the dual lidar retrieval. The single lidar 4DVAR has proven to retrieve accurate flow fields even without the cross-beam information. The turbulent flow characteristics of the retrieved 3D wind and temperature field are studied. A number of coherent structures have been identified by the proper orthogonal decomposition method. The representation of instantaneous snapshots by high-ranking eigenmodes is examined by the reconstruction of reduced-order flow fields. The Lagrangian particle dispersion model has been successfully applied to predict turbulent dispersion in the convective and stable urban ABL. The effects of different source locations and heights have been examined. The vertical mixing is slower in the stable

  16. Four-dimensional optical coherence tomography imaging of total liquid ventilated rats

    Science.gov (United States)

    Kirsten, Lars; Schnabel, Christian; Gaertner, Maria; Koch, Edmund

    2013-06-01

    Optical coherence tomography (OCT) can be utilized for the spatially and temporally resolved visualization of alveolar tissue and its dynamics in rodent models, which allows the investigation of lung dynamics on the microscopic scale of single alveoli. The findings could provide experimental input data for numerical simulations of lung tissue mechanics and could support the development of protective ventilation strategies. Real four-dimensional OCT imaging permits the acquisition of several OCT stacks within one single ventilation cycle. Thus, the entire four-dimensional information is directly obtained. Compared to conventional virtual four-dimensional OCT imaging, where the image acquisition is extended over many ventilation cycles and is triggered on pressure levels, real four-dimensional OCT is less vulnerable against motion artifacts and non-reproducible movement of the lung tissue over subsequent ventilation cycles, which widely reduces image artifacts. However, OCT imaging of alveolar tissue is affected by refraction and total internal reflection at air-tissue interfaces. Thus, only the first alveolar layer beneath the pleura is visible. To circumvent this effect, total liquid ventilation can be carried out to match the refractive indices of lung tissue and the breathing medium, which improves the visibility of the alveolar structure, the image quality and the penetration depth and provides the real structure of the alveolar tissue. In this study, a combination of four-dimensional OCT imaging with total liquid ventilation allowed the visualization of the alveolar structure in rat lung tissue benefiting from the improved depth range beneath the pleura and from the high spatial and temporal resolution.

  17. Objective assessment of cosmetic outcome after targeted intraoperative radiotherapy in breast cancer

    DEFF Research Database (Denmark)

    Keshtgar, Mohammed R S; Williams, Norman R; Bulsara, Max

    2013-01-01

    and thus impair cosmesis further, so we objectively evaluated the aesthetic outcome of patients within the TARGIT randomised controlled trial. We have used an objective assessment tool for evaluation of cosmetic outcome. Frontal digital photographs were taken at baseline (before TARGIT or EBRT) and yearly...... in a randomised setting, the aesthetic outcome of patients demonstrates that those treated with TARGIT have a superior cosmetic result to those patients who received conventional external beam radiotherapy....

  18. Holomorphic classification of four-dimensional surfaces in C{sup 3}

    Energy Technology Data Exchange (ETDEWEB)

    Beloshapka, V K [M. V. Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Moscow (Russian Federation); Ezhov, V V [University of Adelaide (Australia); Schmalz, G [University of New England, Armidale (Australia)

    2008-06-30

    We use the method of model surfaces to study real four-dimensional submanifolds of C{sup 3}. We prove that the dimension of the holomorphic symmetry group of any germ of an analytic four-dimensional manifold does not exceed 5 if this dimension is finite. (There are only two exceptional cases of infinite dimension.) The envelope of holomorphy of the model surface is calculated. We construct a normal form for arbitrary germs and use it to give a holomorphic classification of completely non-degenerate germs. It is shown that the existence of a completely non-degenerate CR-structure imposes strong restrictions on the topological structure of the manifold. In particular, the four-sphere S{sup 4} admits no completely non-degenerate embedding into a three-dimensional complex manifold.

  19. Four-dimensional Microscope-Integrated Optical Coherence Tomography to Visualize Suture Depth in Strabismus Surgery.

    Science.gov (United States)

    Pasricha, Neel D; Bhullar, Paramjit K; Shieh, Christine; Carrasco-Zevallos, Oscar M; Keller, Brenton; Izatt, Joseph A; Toth, Cynthia A; Freedman, Sharon F; Kuo, Anthony N

    2017-02-14

    The authors report the use of swept-source microscope-integrated optical coherence tomography (SS-MIOCT), capable of live four-dimensional (three-dimensional across time) intraoperative imaging, to directly visualize suture depth during lateral rectus resection. Key surgical steps visualized in this report included needle depth during partial and full-thickness muscle passes along with scleral passes. [J Pediatr Ophthalmol Strabismus. 2017;54:e1-e5.]. Copyright 2017, SLACK Incorporated.

  20. Comparative study on four dimensional GLV method and ISD method in elliptic scalar multiplication

    Science.gov (United States)

    Antony, Siti Noor Farwina Mohamad Anwar; Kamarulhaili, Hailiza

    2017-08-01

    In this paper, we reviewed and revisited two integer decomposition methods, namely the four dimensional GLV method and the ISD method. In 2001, Gallant, Lambert and Vanstone (GLV) introduced the GLV method. Number of variants of GLV methods were developed since then mainly focusing on the extension of the GLV method to higher dimension. Starting with two dimensional GLV up to eight dimensional GLV method was proposed until the year 2014. All these variants adopted single layer decomposition. However, in 2014 the ISD method was proposed where this method employed a two layers decomposition technique. The ISD method is similar to the four dimensional GLV method in terms of number of decompositions performed, but it involved sub-decomposition process. Both methods used similar approaches to compute the decomposed scalars, namely the lattice method, shortest vector problem and efficiently computable endomorphism. In the four dimensional GLV method, two endomorphism were used, Frobenius endomorphism and GLV endomorphism while in the ISD method three GLV endomorphism were used to compute the decomposed scalars.

  1. Higher-order gravity in higher dimensions: geometrical origins of four-dimensional cosmology?

    Energy Technology Data Exchange (ETDEWEB)

    Troisi, Antonio [Universita degli Studi di Salerno, Dipartimento di Fisica ' ' E.R. Caianiello' ' , Salerno (Italy)

    2017-03-15

    Determining the cosmological field equations is still very much debated and led to a wide discussion around different theoretical proposals. A suitable conceptual scheme could be represented by gravity models that naturally generalize Einstein theory like higher-order gravity theories and higher-dimensional ones. Both of these two different approaches allow one to define, at the effective level, Einstein field equations equipped with source-like energy-momentum tensors of geometrical origin. In this paper, the possibility is discussed to develop a five-dimensional fourth-order gravity model whose lower-dimensional reduction could provide an interpretation of cosmological four-dimensional matter-energy components. We describe the basic concepts of the model, the complete field equations formalism and the 5-D to 4-D reduction procedure. Five-dimensional f(R) field equations turn out to be equivalent, on the four-dimensional hypersurfaces orthogonal to the extra coordinate, to an Einstein-like cosmological model with three matter-energy tensors related with higher derivative and higher-dimensional counter-terms. By considering the gravity model with f(R) = f{sub 0}R{sup n} the possibility is investigated to obtain five-dimensional power law solutions. The effective four-dimensional picture and the behaviour of the geometrically induced sources are finally outlined in correspondence to simple cases of such higher-dimensional solutions. (orig.)

  2. Quantitative MR imaging in planning and assessing novel cancer treatments Radiotherapy

    CERN Document Server

    Baustert, I C

    2001-01-01

    Novel treatments in cancer, like conformal radiotherapy and anticancer drugs, require new MRI techniques to assess their benefits and potential. In conformal radiotherapy, MRI can be used to measure the shape and dose of the conformed radiation field in dose sensitive gel test-objects thus validating the predicted dose computed by complex programs. In antiangiogenic drug treatment, the vascular dysfunction of the tumour can be assessed by MRI prior to treatment. Response to treatment may also be monitored by measuring the changes in vascular function. In this thesis, MRI of polyacrylamide gels is investigated as a 3D dosimeter for conformal radiotherapy treatment planning. Quantitative MRI sequences capable of measuring the wide range of T2 values typically expected in gel dosimetry, are identified. Different T2 measurement methods are compared in terms of accuracy, signal to noise ratio and acquisition time. Examples of a complex dose distribution in 2D and 3D are presented and compared to the planned dose p...

  3. Chemo-radiotherapy induced oral mucositis during IMRT for head and neck cancer - An assessment.

    Science.gov (United States)

    Nagarajan, Karthika

    2015-05-01

    This study is conducted mainly to evaluate the changes in quality and quantity of oral epithelial cells during the course of IMRT. 30 Patients undergoing chemo-radiotherapy were followed through course of treatment. They were compared with a group of age- and sex-matched healthy individuals. The procedure involved WHO clinical scoring, collection of oral washings and preparation of buccal smears from both study group and control group. The changes occurred were recorded as a way of assessing the severity of oral mucositis. revealed a significant occurrence of oral mucositis in almost all patients during weekly follow up. There was a significant increase in percentage of viable buccal epithelial cells in study group when compared to normal controls (P<0.005) during and at the end of chemo-radiotherapy. quantification of oral mucositis can be done at cellular level by determining the oral mucosal cell viability and their maturation during IMRT.

  4. Prospective assessment of the salivary function by parotid scintigraphy after radiotherapy of 27 nasopharyngeal cancers; evaluation prospective de la fonction salivaire par scintigraphie parotidienne apres radiotherapie de 27 cancers du nasopharynx

    Energy Technology Data Exchange (ETDEWEB)

    Mnejja, W.; Ghorbal, L.; Daoud, J. [Service de radiotherapie oncologique, CHU Habib-Bourguiba, Sfax (Tunisia); Kallel, F.; Guermazi, F. [Service de medecine nucleaire, CHU Habib-Bourguiba, Sfax (Tunisia); Frikha, M. [Service de carcinologie medicale, CHU Habib-Bourguiba, Sfax (Tunisia)

    2011-10-15

    As xerostomia is the main complication after radiotherapy of nasopharyngeal carcinomas, and affects life quality, this study aims at objectively assess the salivary function after radiotherapy of a nasopharyngeal cancer by parotid scintigraphy. 27 seven patients have been treated by radiotherapy with or without chemotherapy. Results are analyzed in terms of salivary toxicity, change of secretion function. No correlation was found between the xerostomia severity and scintigraphy results. Short communication

  5. Patient-specific modelling of whole heart anatomy, dynamics and haemodynamics from four-dimensional cardiac CT images.

    Science.gov (United States)

    Mihalef, Viorel; Ionasec, Razvan Ioan; Sharma, Puneet; Georgescu, Bogdan; Voigt, Ingmar; Suehling, Michael; Comaniciu, Dorin

    2011-06-06

    There is a growing need for patient-specific and holistic modelling of the heart to support comprehensive disease assessment and intervention planning as well as prediction of therapeutic outcomes. We propose a patient-specific model of the whole human heart, which integrates morphology, dynamics and haemodynamic parameters at the organ level. The modelled cardiac structures are robustly estimated from four-dimensional cardiac computed tomography (CT), including all four chambers and valves as well as the ascending aorta and pulmonary artery. The patient-specific geometry serves as an input to a three-dimensional Navier-Stokes solver that derives realistic haemodynamics, constrained by the local anatomy, along the entire heart cycle. We evaluated our framework with various heart pathologies and the results correlate with relevant literature reports.

  6. Computerized patient reported symptom assessment in radiotherapy: a pilot randomized, controlled trial

    Science.gov (United States)

    Holliday, Emma B.; Nail, Lillian M.; Lyons, Karen S.; Hribar, Michelle R.; Thomas, Charles R.

    2016-01-01

    Purpose Computer-based, patient-reported symptom survey tools have been described for patients undergoing chemotherapy. We hypothesized that patients undergoing radiotherapy might also benefit, so we developed a computer application to acquire symptom ratings from patients and generate summaries for use at point of care office visits and conducted a randomized-controlled pilot trial to test its feasibility. Methods Subjects were randomized prior to beginning radiotherapy. Both control and intervention group subjects completed the computerized symptom assessment, but only for the intervention group were printed symptom summaries made available before each weekly office visit. Metrics compared included the Global Distress Index (GDI), concordance of patient-reported symptoms and symptoms discussed by the physician and numbers of new and/or adjusted symptom management medications prescribed. Results 112 patients completed the study: 54 in the control and 58 in the intervention arms. There were no differences in GDI over time between the control and intervention groups. In the intervention group, more patient-reported symptoms were actually discussed in radiotherapy office visits: 46/202 vs. 19/230. A sensitivity analysis to account for within-subjects correlation yielded 23.2% vs. 10.3% (p=.03). Medications were started or adjusted at 15.4% (43/280) of control visits compared to 20.4% (65/319) of intervention visits (p=.07). Conclusions This computer application is easy to use and makes extensive patient-reported outcome data available at the point of care. Although no differences were seen in symptom trajectory, patients who had printed symptom summaries had improved communication during office visits and a trend towards more active symptom management during radiotherapy. PMID:26471280

  7. Breast cancer cells form primary tumors on ex vivo four-dimensional lung model.

    Science.gov (United States)

    Pence, Kristi A; Mishra, Dhruva K; Thrall, Michael; Dave, Bhuvanesh; Kim, Min P

    2017-04-01

    Breast cancer mortality is most common in cancer in women, and there are no ex vivo models that can capture the primary growth of tumor with fidelity to the in vivo tumor growth. In this study, we grew human breast cancer cell lines in an acellular lung matrix of the ex vivo four-dimensional lung model to determine if they form primary tumor and the extent to which they mimic the histology and characteristics of the human tumors. Rat lungs were harvested, decellularized, and placed in a bioreactor. To study the primary tumor growth, we seeded the lung via the trachea with human breast cancer cells SUM159, MCF7, or MDMB231 and perfused the pulmonary artery with oxygenated media. Lobectomies were performed and processed for hematoxylin and eosin, Ki-67, caspase-3, estrogen receptor, and progesterone receptor antibodies. All three cell lines grew in the ex vivo four-dimensional model and formed perfusable tumor nodules with similar histology and morphology as the primary tumors. SUM159 and MDAMB231 showed higher proliferation and apoptotic indices than MCF7. In addition, MCF7 retained its estrogen receptor and progesterone receptor positivity, whereas SUM159 and MDAMB 231 did not have any staining. Overall, our study showed that human breast cancer cells can be grown on the ex vivo four-dimensional lung model, which then form primary tumor nodules that mimic the morphology and histology of the original tumor. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. New black hole, string and membrane solutions of the four-dimensional heterotic string

    CERN Document Server

    Duff, Michael J; Minasian, R; Rahmfeld, J; Khuri, Ramzi R.; Minasian, Ruben; Rahmfeld, Joachim

    1994-01-01

    We present solutions of the low-energy four-dimensional heterotic string corresponding to $p$-branes with $p=0,1,2$, which are characterized by a mass per unit $p$-volume, ${\\cal M}_{p+1}$, and topological ``magnetic'' charge, $g_{p+1}$. In the extremal limit, $\\sqrt{2} \\kappa {\\cal M}_{p+1} = g_{p+1}$, they reduce to the recently discovered non-singular supersymmetric monopole, string and domain wall solutions. A novel feature is that the solutions involve both the dilaton and the modulus fields. In particular, the effective scalar coupling to the Maxwell field, $e^{-\\alpha \\phi} F_{\\mu\

  9. Gravitational matter-antimatter asymmetry and four-dimensional Yang-Mills gauge symmetry

    Science.gov (United States)

    Hsu, J. P.

    1981-01-01

    A formulation of gravity based on the maximum four-dimensional Yang-Mills gauge symmetry is studied. The theory predicts that the gravitational force inside matter (fermions) is different from that inside antimatter. This difference could lead to the cosmic separation of matter and antimatter in the evolution of the universe. Moreover, a new gravitational long-range spin-force between two fermions is predicted, in addition to the usual Newtonian force. The geometrical foundation of such a gravitational theory is the Riemann-Cartan geometry, in which there is a torsion. The results of the theory for weak fields are consistent with previous experiments.

  10. Four-dimensional (4D) tracking of high-temperature microparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhehui, E-mail: zwang@lanl.gov; Liu, Q.; Waganaar, W. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Fontanese, J.; James, D.; Munsat, T. [University of Colorado, Boulder, Colorado 80309 (United States)

    2016-11-15

    High-speed tracking of hot and molten microparticles in motion provides rich information about burning plasmas in magnetic fusion. An exploding-wire apparatus is used to produce moving high-temperature metallic microparticles and to develop four-dimensional (4D) or time-resolved 3D particle tracking techniques. The pinhole camera model and algorithms developed for computer vision are used for scene calibration and 4D reconstructions. 3D positions and velocities are then derived for different microparticles. Velocity resolution approaches 0.1 m/s by using the local constant velocity approximation.

  11. A four-dimensional model with the fermionic determinant exactly evaluated

    Science.gov (United States)

    Mignaco, J. A.; Rego Monteiro, M. A.

    1986-07-01

    A method is presented to compute the fermion determinant of some class of field theories. By this method the following results of the fermion determinant in two dimensions are easily recovered: (i) Schwinger model without reference to a particular gauge. (ii) QCD in the light-cone gauge. (iii) Gauge invariant result of QCD. The method is finally applied to give an analytical solution of the fermion determinant of a four-dimensional, non-abelian, Dirac-like theory with massless fermions interacting with an external vector field through a pseudo-vectorial coupling. Fellow of the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brazil.

  12. Four-dimensional quantum oscillator and magnetic monopole with U(1) dynamical group

    Science.gov (United States)

    Bakhshi, Z.; Panahi, H.; Golchehre, S. G.

    2017-09-01

    By using an appropriate transformation, it was shown that the quantum system of four-dimensional (4D) simple harmonic oscillator can describe the motion of a charged particle in the presence of a magnetic monopole field. It was shown that the Dirac magnetic monopole has the hidden algebra of U(1) symmetry and by reducing the dimensions of space, the U(1) × U(1) dynamical group for 4D harmonic oscillator quantum system was obtained. Using the group representation and based on explicit solution of the obtained differential equation, the spectrum of system was calculated.

  13. Choice of evolutional parameter within a framework of four-dimensional symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Chang, T.

    1988-06-01

    Within the context of the variational principle, there is the freedom to choose specific evolutional parameters. Different parameters can be associated with physical time, while allowing the physical laws to preserve the property of four-dimensional symmetry. In this sense, the concept of time has flexibility. Besides proper time and relativistic time, another natural choice emerges, which is called the generalized Galilean time. We study the impact of this choice here. This approach provides a deeper understanding of the theory of special relativity, and it also provides a new basis to study other space-time theories.

  14. An accessible four-dimensional treatment of Maxwell's equations in terms of differential forms

    Science.gov (United States)

    Sá, Lucas

    2017-03-01

    Maxwell’s equations are derived in terms of differential forms in the four-dimensional Minkowski representation, starting from the three-dimensional vector calculus differential version of these equations. Introducing all the mathematical and physical concepts needed (including the tool of differential forms), using only knowledge of elementary vector calculus and the local vector version of Maxwell’s equations, the equations are reduced to a simple and elegant set of two equations for a unified quantity, the electromagnetic field. The treatment should be accessible for students taking a first course on electromagnetism.

  15. Quasinormal modes of four-dimensional topological nonlinear charged Lifshitz black holes

    Energy Technology Data Exchange (ETDEWEB)

    Becar, Ramon [Universidad Cato lica de Temuco, Departamento de Ciencias Matematicas y Fisicas, Temuco (Chile); Gonzalez, P.A. [Universidad Diego Portales, Facultad de Ingenieria, Santiago (Chile); Vasquez, Yerko [Universidad de La Serena, Departamento de Fisica, Facultad de Ciencias, La Serena (Chile)

    2016-02-15

    We study scalar perturbations of four- dimensional topological nonlinear charged Lifshitz black holes with spherical and plane transverse sections, and we find numerically the quasinormal modes for scalar fields. Then we study the stability of these black holes under massive and massless scalar field perturbations. We focus our study on the dependence of the dynamical exponent, the nonlinear exponent, the angular momentum, and the mass of the scalar field in the modes. It is found that the modes are overdamped, depending strongly on the dynamical exponent and the angular momentum of the scalar field for a spherical transverse section. In contrast, for plane transverse sections the modes are always overdamped. (orig.)

  16. Four-dimensional conversion for spiritual leadership development: A missiological approach for African churches

    Directory of Open Access Journals (Sweden)

    Kalemba Mwambazambi

    2014-02-01

    Full Text Available The process of a four-dimensional conversion and/or transformation strives in helping the leadership of an organisation, especially such as the church, with practical ways that may lead to the development of an effective leadership by observing the four important aspects of human spirituality as elaborated on in the article. The spiritual, intellectual, moral and socio-political dimensions of the transformation can be catered for so that the complete inner being of humans, as well as their social and political attitudes and behaviours, can equally be transformed to maximum spiritual, personal and socio-political profitability. Mutombo-Mukendi demonstrates that the need for a spiritual leadership that can contribute to an effective transformation of Africa is dire, both for the church and the larger community. The real challenge is how to develop such leadership. This article provides intentional and practical ways that may lead to the development of the needed leadership. Four-dimensional transformation of people can be planned and carried out both in the church arena and in the surrounding communities. Skills development and transfer can also take place when skilled people from the church work with unskilled people from the community.

  17. Extra-dimensional curvature suppression of the effective four-dimensional vacuum energy density

    Science.gov (United States)

    Guendelman, E. I.

    2012-05-01

    Considering a very large number of extra dimensions, N → ∞, we show that in the effective four-dimensional picture, to leading order in N, both the cosmological constant in N + 4 dimensions and the curvature of the extra dimensions (curved as spheres) give the same type of contributions. Furthermore, in this limit, the extra-dimensional curvature naturally suppresses the effect of a positive cosmological constant, so that the resulting effective potential governing the vacuum energy in the effective 4 - D picture has a leading 1/N dependence (i.e. vanishing in the large N limit). We can understand qualitatively this effect in a heuristic picture by thinking that both visible and extra dimensions have an equal sharing of the curvature caused by Λ. In this case when increasing the overall number of dimensions by adding N extra dimensions, then if N is large, the visible dimensions do not have to curve too much; hence, a small four-dimensional vacuum energy follows. In the large N picture, the potential can also be stabilized by a small (i.e. vanishing at large N) expectation value of a four-index field strength.

  18. Extra Dimensional Curvature Supression of the Effective Four Dimensional Vacuum Energy Density

    CERN Document Server

    Guendelman, E I

    2012-01-01

    Considering a very large number of extra dimensions, $N\\rightarrow \\infty$, we show that in the effective four dimensional picture, to leading order in $N$, both the cosmological constant in $N+4$ dimensions and the curvature of the extra dimensions (curved as spheres) give the same type of contributions. Furthermore in this limit, the extra dimensional curvature naturally supress the effect of a positive Cosmological Constant, so that the resulting effective potential governing the vacuum energy in the effective $4-D$ picture has a leading 1/N dependence (i.e. vanishing in the large $N$ limit). We can understand qualitatively this effect in a heuristic picture, by thinking that all dimensions, both visible and extra have an equal sharing of the curvature caused by $\\Lambda$, in this case when increasing the overall number of dimensions by adding $N$ extra dimensions, then if $N$ is large, the visible dimensions do not have to curve too much, hence a small four dimensional vacuum energy follows. In the large ...

  19. Effect of Fractionated Dose of Radiotherapy on Oral Mucosa in Head and Neck Cancer Patients: A Cytological Assessment.

    Science.gov (United States)

    Khan, S; Feroz, Sma; Jain, M; Mathur, V; Khan, Sameera

    2016-05-01

    Cancer therapy couples with it a plethora of complications of short and long term effects which can be so distressing that patient may tolerate only lower less-effective doses of therapy, may postpone treatments or will discontinue treatment entirely. Fractionated dose of radiotherapy coupled with therapy induce local or systemic infections due to high cellular turnover rates of the oral mucosa, diverse and complex microflora and trauma to oral tissues. Several mucosal abnormalities often results in epithelial and glandular destruction and inflammation, which can be so devastating that it may cause atypical changes on the area exposed to radiation. Thus, the aim of this study was to investigate the feasibility of using cytological evaluation to detect oral epithelial atypia among Head and Neck cancer patients receiving fractionated dose of radiotherapy. Study was conducted on 125 head and neck cancer patients receiving radiotherapy. Subjects were divided into 5 study groups on the basis of fractionated dose of radiotherapy from 10th-50th fractions respectively. Mucosal changes were evaluated by exfoliative cytology and atypical changes and inflammatory cell infiltration were assessed. Without prior knowledge of the subjects' group, oral epithelial atypia was detected with increase fractionated dose of radiation. Dense inflammatory nfiltrate were identified in nearly all study groups irrespective of dose of radiotherapy. Cytological atypia and inflammatory infiltrates were detected after exposure to radiotherapy.

  20. Emerging radiotherapy technology in a developing country: A single Brazilian institution assessment of stereotactic body radiotherapy application.

    Science.gov (United States)

    Moraes, Fabio Ynoe; Bonifacio, Lorine Arias; Neves-Junior, Wellington Pimenta; Hanna, Samir Abdallah; Abreu, Carlos Eduardo Cintra Vita; Arruda, Fernando Freire; Silva, João Luis Fernandes; Carvalho, Heloisa Andrade

    2016-11-01

    To provide a quantitative profile of the indications and use of stereotactic body radiotherapy (SBRT) in a developing country oncology-based institution. In addition, to describe the patients' and treatment characteristics, and to provide a temporal analysis. SBRT patients treated from 2007 to 2015 were retrospectively evaluated by two independently investigators. Data were stratified and compared in two periods: first experience (FE) (May 2007 to April 2011), and following experience (FollowE) (May 2011 to April 2015). The following parameters were compared between the groups: total number of treated patients and lesions, treatment site, additional image fusion used, formal protocol adoption, and SBRT planning technique. One hundred and seventy-six (176) patients with 191 lesions were treated: 34 (18%) lesions in the FE and 157 (82%) lesions in FollowE. The majority of lesions were metastases (60.3%), and lung (60.2%) was the most common treatment site, followed by spine (31%), and others (8.8%). An average of 1.4 (±0.6) additional imaging exams for delineation was performed. Conformal 3D radiotherapy planning technique was used in 64.4%, and intensity modulated radiotherapy (IMRT) or volumetric-modulated arc therapy (VMAT) in the remaining 35.6% (p=0.0001). Higher rates of curative treatments were observed in FE, as well as more lung lesions, patients ≥ 70 years, 3D conformal, number of additional images and ECOG 0, and all presented p<0.05. The global rate of protocol statement was 79%, lung treatment being the most stated. SBRT application is rapidly increasing in our setting. Treatment sites and planning techniques are becoming more diversified and complex.

  1. Emerging radiotherapy technology in a developing country: A single Brazilian institution assessment of stereotactic body radiotherapy application

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Fabio Ynoe; Bonifacio, Lorine Arias; Neves-Junior, Wellington Pimenta; Hanna, Samir Abdallah; Abreu, Carlos Eduardo Cintra Vita; Arruda, Fernando Freire; Silva, Joao Luis Fernandes; Carvalho, Heloisa Andrade, E-mail: fymoraes@gmail.com [Hospital Sirio-Libanes, Sao Paulo, SP(Brazil)

    2016-11-15

    Objective: To provide a quantitative profile of the indications and use of stereotactic body radiotherapy (SBRT) in a developing country oncology-based institution. In addition, to describe the patient and treatment characteristics, and to provide a temporal analysis. Method: SBRT patients treated from 2007 to 2015 were retrospectively evaluated by two independently investigators. Data were stratified and compared in two periods: first experience (FE) (May 2007 to April 2011), and following experience (FollowE) (May 2011 to April 2015). The following parameters were compared between the groups: total number of treated patients and lesions, treatment site, additional image fusion used, formal protocol adoption, and SBRT planning technique. Results: One hundred and seventy-six (176) patients with 191 lesions were treated: 34 (18%) lesions in the FE and 157 (82%) lesions in FollowE. The majority of lesions were metastases (60.3%), and lung (60.2%) was the most common treatment site, followed by spine (31%), and others (8.8%). An average of 1.4 (±0.6) additional imaging exams for delineation was performed. Conformal 3D radiotherapy planning technique was used in 64.4%, and intensity modulated radiotherapy (IMRT) or volumetric-modulated arc therapy (VMAT) in the remaining 35.6% (p=0.0001). Higher rates of curative treatments were observed in FE, as well as more lung lesions, patients ≥ 70 years, 3D conformal, number of additional images and ECOG 0, and all presented p<0.05. The global rate of protocol statement was 79%, lung treatment being the most stated. Conclusion: SBRT application is rapidly increasing in our setting. Treatment sites and planning techniques are becoming more diversified and complex. (author)

  2. Validation of the four-dimensional symptom questionnaire (4DSQ) and prevalence of psychological symptoms in orthopedic shoulder patients

    NARCIS (Netherlands)

    Koorevaar, Rinco C. T.; Terluin, Berend; van't Riet, Esther; Madden, Kim; Bulstra, Sjoerd K.

    Psychological problems are common in shoulder patients. A validated psychological questionnaire measuring clinically relevant psychological symptoms (including distress, depression, anxiety, and somatization) in shoulder patients is lacking. The Four-Dimensional Symptom Questionnaire (4DSQ) is a

  3. Assessing organizational citizenship behavior in the French context: evidence for the four-dimensional model.

    Science.gov (United States)

    Paillé, Pascal

    2009-03-01

    Although researchers have extensively studied organizational citizenship behavior (OCB) in the U.S. context, OCB measurement has received relatively limited attention in other contexts, specifically in the French-language context. Using 2 samples (for Study 1, N=292; for Study 2, N=355), the author investigated OCB in a French-language context. Using an exploratory factorial analysis in Study 1, the author found a 4-factor model (altruism, civic virtue, sportsmanship, helping others). Using a confirmatory factor analysis in Study 2, the author confirmed a 4-factor model. Data provided results that show some differences and similarities between U.S. and French contexts.

  4. New classes of bi-axially symmetric solutions to four-dimensional Vasiliev higher spin gravity

    Energy Technology Data Exchange (ETDEWEB)

    Sundell, Per; Yin, Yihao [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago de Chile (Chile)

    2017-01-11

    We present new infinite-dimensional spaces of bi-axially symmetric asymptotically anti-de Sitter solutions to four-dimensional Vasiliev higher spin gravity, obtained by modifications of the Ansatz used in https://arxiv.org/abs/1107.1217, which gave rise to a Type-D solution space. The current Ansatz is based on internal semigroup algebras (without identity) generated by exponentials formed out of the bi-axial symmetry generators. After having switched on the vacuum gauge function, the resulting generalized Weyl tensor is given by a sum of generalized Petrov type-D tensors that are Kerr-like or 2-brane-like in the asymptotic AdS{sub 4} region, and the twistor space connection is smooth in twistor space over finite regions of spacetime. We provide evidence for that the linearized twistor space connection can be brought to Vasiliev gauge.

  5. The dissociative adsorption of hydrogen: Two-, three-, and four-dimensional quantum simulations

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Halstead, David; Holloway, Stephen

    1990-01-01

    and diffraction on an equal footing. By including a rotational degree of freedom, it is seen that strong orientational effects occur near to the transition state and result in an anisotropic selectivity in the dissociation. By examining the state-to-state scattering probabilities, it is possible to use......A quantum wave packet calculation for the activated dissociative adsorption of H2 is presented. Restricting the motion of the molecule to lie within a plane normal to the surface we have treated all four molecular degrees of freedom exactly. We compare results obtained using two-, three-, and four......-dimensional simulations on the same potential and show that by restricting the molecular orientation, important dynamical effects are lost. The potential employed in the calculations has been obtained using the effective medium approximation. In the simulations it has been possible to treat dissociation, rotations...

  6. Single-nanoparticle phase transitions visualized by four-dimensional electron microscopy

    Science.gov (United States)

    van der Veen, Renske M.; Kwon, Oh-Hoon; Tissot, Antoine; Hauser, Andreas; Zewail, Ahmed H.

    2013-05-01

    The advancement of techniques that can probe the behaviour of individual nanoscopic objects is of paramount importance in various disciplines, including photonics and electronics. As it provides images with a spatiotemporal resolution, four-dimensional electron microscopy, in principle, should enable the visualization of single-nanoparticle structural dynamics in real and reciprocal space. Here, we demonstrate the selectivity and sensitivity of the technique by visualizing the spin crossover dynamics of single, isolated metal-organic framework nanocrystals. By introducing a small aperture in the microscope, it was possible to follow the phase transition and the associated structural dynamics within a single particle. Its behaviour was observed to be distinct from that imaged by averaging over ensembles of heterogeneous nanoparticles. The approach reported here has potential applications in other nanosystems and those that undergo (bio)chemical transformations.

  7. Single-nanoparticle phase transitions visualized by four-dimensional electron microscopy.

    Science.gov (United States)

    van der Veen, Renske M; Kwon, Oh-Hoon; Tissot, Antoine; Hauser, Andreas; Zewail, Ahmed H

    2013-05-01

    The advancement of techniques that can probe the behaviour of individual nanoscopic objects is of paramount importance in various disciplines, including photonics and electronics. As it provides images with a spatiotemporal resolution, four-dimensional electron microscopy, in principle, should enable the visualization of single-nanoparticle structural dynamics in real and reciprocal space. Here, we demonstrate the selectivity and sensitivity of the technique by visualizing the spin crossover dynamics of single, isolated metal-organic framework nanocrystals. By introducing a small aperture in the microscope, it was possible to follow the phase transition and the associated structural dynamics within a single particle. Its behaviour was observed to be distinct from that imaged by averaging over ensembles of heterogeneous nanoparticles. The approach reported here has potential applications in other nanosystems and those that undergo (bio)chemical transformations.

  8. Power Doppler flow mapping and four-dimensional ultrasound for evaluating tubal patency compared with laparoscopy.

    Science.gov (United States)

    Soliman, Amr A; Shaalan, Waleed; Abdel-Dayem, Tamer; Awad, Elsayed Elbadawy; Elkassar, Yasser; Lüdders, Dörte; Malik, Eduard; Sallam, Hassan N

    2015-12-01

    To study the accuracy of four-dimensional (4D) ultrasound and power Doppler flow mapping in detecting tubal patency in women with sub-/infertility, and compare it with laparoscopy and chromopertubation. A prospective study. The study was performed in the outpatient clinic and infertility unit of a university hospital. The sonographic team and laparoscopic team were blinded to the results of each other. Women aged younger than 43 years seeking medical advice due to primary or secondary infertility and who planned to have a diagnostic laparoscopy performed, were recruited to the study after signing an informed consent. All of the recruited patients had power Doppler flow mapping and 4D hysterosalpingo-sonography by injecting sterile saline into the fallopian tubes 1 day before surgery. Registering Doppler signals, while using power Doppler, both at the tubal ostia and fimbrial end and the ability to demonstrate the course of the tube especially the isthmus and fimbrial end, while using 4D mode, was considered a patent tube. Out of 50 recruited patients, 33 women had bilateral patent tubes and five had unilateral patent tubes as shown by chromopertubation during diagnostic laparoscopy. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for two-dimensional power Doppler hysterosalpingography were 94.4%, 100%, 100%, 89.2%, and 96.2%, respectively and for 4D ultrasound were 70.4%, 100%, 100%, 70.4%, and 82.6%, respectively. Four-dimensional saline hysterosalpingography has acceptable accuracy in detecting tubal patency, but is surpassed by power Doppler saline hysterosalpingography. Power Doppler saline hysterosalpingography could be incorporated into the routine sub-/infertility workup. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. Assessment of radiotherapy photon beams: A practical and low cost methodology

    Science.gov (United States)

    Reis, C. Q. M.; Nicolucci, P.

    2017-02-01

    Dosimetric properties of radiation beams used in radiotherapy are directly related to the energy spectrum produced by the treatment unit. Therefore, the development of methodologies to evaluate in a simple and accurate way the spectra of clinical beams can help establishing the quality control of the treatment. The purpose of this study is to present a practical and low cost methodology for determining primary spectra of radiotherapy photon beams from transmission measurements in attenuators of aluminum and using the method of the inverse Laplace transform. Monte Carlo simulation with PENELOPE code was used in order to evaluate and validate the reconstructed spectra by the calculation of dosimetric parameters that characterize the beam. Percentage depth dose values simulated with a 6 MV reconstructed spectrum shows maximum difference of 4.4% when compared to values measured at the corresponding clinical beam. For a 10 MV beam that difference was around 4.2%. Results obtained in this study confirm the adequacy of the proposed methodology for assessing primary photon beams produced by clinical accelerators.

  10. Assessment of glioma response to radiotherapy using 3D pulsed-continuous arterial spin labeling and 3D segmented volume

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peng; Li, Jianrui; Diao, Qiang; Lin, YuanKai; Zhang, Jun; Li, Lin; Yang, Gang; Fang, Xiaokun; Li, Xie; Chen, YingQi; Zheng, Ling, E-mail: lingzheng1989@yeah.net; Lu, Guangming, E-mail: guangminglu1905@163.com

    2016-11-15

    Background: Gliomas are the most common primary brain tumors in adults, in some cases, radiotherapy may be the preferred treatment option especially for elderly people who cannot endure surgery. Therefore, it is necessary to evaluate the effects of radiotherapy on glioma. Arterial spin labeling (ASL) is an MR imaging technique that allows for a quantitative determination of cerebral blood flow (CBF) noninvasively. Tumor volume is still an important determinant for evaluating treatment response. The purpose of this study was to investigate the relationship between the tumor perfusion parameters and tumor volume and assess the effects of radiotherapy on glioma using pulsed-continuous arterial spin labeling (pcASL) technique. Methods: 35 patients with gliomas, histologically classified as low-grade group (n = 16) and high-grade group (n = 19), treated with radiotherapy only or before using other therapies were included in this study. MR examinations, including T1 weighted image and pcASL, were performed before and 4, 8, 12, 16 weeks after radiotherapy. Regional CBF of normal tissue, mean tumor blood flow (TBF{sub mean}), maximum tumor blood flow (TBF{sub max}), and tumor volume were evaluated at each time point. Both the percentage change in CBF (CBF ratio), TBF{sub mean} (TBF{sub mean} ratio), TBF{sub max} (TBF{sub max} ratio) and the percentage change in tumor volume (volume ratio) were calculated using values obtained before and after radiotherapy. The correlation between the volume ratio and CBF ratio, TBF{sub mean} ratio, TBF{sub max} ratio was assessed using linear regression analysis and Pearson’s correlation. Results: The TBF{sub mean} and TBF{sub max} of high-grade gliomas were significantly higher than that of low-grade group. In high-grade group, a strong correlation was demonstrated between the tumor volume and the TBF{sub max} before radiotherapy (R{sup 2} = 0.35, r{sub s} = 0.59, p < 0.05). There was also a significant correlation between the TBF

  11. Intra- and interobserver repeatability of fetal cardiac examination using four-dimensional spatiotemporal image correlation in each trimester of pregnancy.

    Science.gov (United States)

    Bennasar, M; Martínez, J M; Gómez, O; Figueras, F; Olivella, A; Puerto, B; Gratacós, E

    2010-03-01

    To assess the intra- and interobserver repeatability of the evaluation of fetal cardiac structures and measurements using spatiotemporal image correlation (STIC) technology in each trimester of pregnancy. Four-dimensional (4D)-STIC volumes from 150 low-risk pregnancies were acquired at first-, second- or third-trimester scan for later analysis by two different reviewers. A total of 19 items, including the evaluation of 14 structures as well as five measurements of the fetal heart, were evaluated. The reliability of qualitative variables was evaluated using Cohen's kappa and absolute agreement analysis while that of quantitative parameters was assessed using the intraclass correlation coefficient (ICC). Forty-five, 47 and 47 STIC volumes were included in the final analysis from the first, second and third trimesters, respectively. For the evaluation of cardiac structures, good or excellent intra- and interobserver agreement (kappa > 0.6) was obtained in 12/14 and 9/14, respectively, while absolute agreement was > 90% for most structures evaluated. Regarding the quantitative cardiac measurements, ICC values were above 0.90 for all but cardiac axis (intraobserver ICC, 0.81 and interobserver ICC, 0.61). There were no significant differences in the repeatability values observed for qualitative or quantitative parameters among the trimesters of pregnancy. Cardiac examination from 4D-STIC volumes showed a high repeatability between and within observers in each trimester of pregnancy. (c) 2010 ISUOG. Published by John Wiley & Sons, Ltd.

  12. Quantitative multiparametric MRI assessment of glioma response to radiotherapy in a rat model.

    Science.gov (United States)

    Hong, Xiaohua; Liu, Li; Wang, Meiyun; Ding, Kai; Fan, Ying; Ma, Bo; Lal, Bachchu; Tyler, Betty; Mangraviti, Antonella; Wang, Silun; Wong, John; Laterra, John; Zhou, Jinyuan

    2014-06-01

    The inability of structural MRI to accurately measure tumor response to therapy complicates care management for patients with gliomas. The purpose of this study was to assess the potential of several noninvasive functional and molecular MRI biomarkers for the assessment of glioma response to radiotherapy. Fourteen U87 tumor-bearing rats were irradiated using a small-animal radiation research platform (40 or 20 Gy), and 6 rats were used as controls. MRI was performed on a 4.7 T animal scanner, preradiation treatment, as well as at 3, 6, 9, and 14 days postradiation. Image features of the tumors, as well as tumor volumes and animal survival, were quantitatively compared. Structural MRI showed that all irradiated tumors still grew in size during the initial days postradiation. The apparent diffusion coefficient (ADC) values of tumors increased significantly postradiation (40 and 20 Gy), except at day 3 postradiation, compared with preradiation. The tumor blood flow decreased significantly postradiation (40 and 20 Gy), but the relative blood flow (tumor vs contralateral) did not show a significant change at most time points postradiation. The amide proton transfer weighted (APTw) signals of the tumor decreased significantly at all time points postradiation (40 Gy), and also at day 9 postradiation (20 Gy). The blood flow and APTw maps demonstrated tumor features that were similar to those seen on gadolinium-enhanced T1-weighted images. Tumor ADC, blood flow, and APTw were all useful imaging biomarkers by which to predict glioma response to radiotherapy. The APTw signal was most promising for early response assessment in this model. © The Author(s) 2013. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Quality of life assessment with different radiotherapy schedules in palliative management of advanced carcinoma esophagus: A prospective randomized study

    Directory of Open Access Journals (Sweden)

    Shaveta Mehta

    2008-01-01

    Full Text Available Aim: To investigate the quality of life (QOL of patients with advanced carcinoma esophagus treated with different palliative radiation schedules. Methods: Sixty-two consecutive patients with inoperable, non-metastatic carcinoma of the esophagus were randomly allocated to Arm-A (external radiotherapy 30 Gy/10 fractions + brachytherapy 12 Gy/two sessions, Arm-B (external radiotherapy 30 Gy /10 fractions and Arm-C (external radiotherapy 20Gy /five fractions. The QOL was assessed using the European Organization for Research and Treatment of Cancer questionnaire at presentation, after treatment and at 3 months follow-up. Results: The mean QOL score improved, in arm-A from 38 to 52 after treatment and 56 at 3 months, in arm-B from 30 to 44 after treatment and 55 at 3 months and in arm-C from 24 to 40 after treatment but decreased to 37 at 3 months. Improvement in dysphagia scores at the first follow-up was 46.1% in arm-A, 25.0% in arm-B and 22.6% in arm-C. The difference was maintained at 3 months, with maximum improvement in arm-A (57.6%. No significant differences were found between the three arms with regard to complications and additional procedures needed for relief of dysphagia. Conclusion: In comparison with external radiotherapy alone, external radiotherapy with intraluminal brachytherapy has shown a trend toward better QOL and consistent dysphagia relief without significant difference in adverse effects.

  14. Prospective assessment of the quality of life before, during and after image guided intensity modulated radiotherapy for prostate cancer

    DEFF Research Database (Denmark)

    Sveistrup, Joen; Mortensen, Ole Steen; Bjørner, Jakob B.

    2016-01-01

    BACKGROUND: Radiotherapy (RT) in combination with androgen deprivation therapy (ADT) for prostate cancer (PCa) carries a risk of gastrointestinal (GI) and genitourinary toxicity, which might affect the quality of life (QoL). The purpose of this study was to assess the QoL in patients with PCa...... before, during and after radiotherapy (RT) and to compare the QoL 1 year after RT to a normal population. METHODS: The QoL was evaluated prospectively by the self-administered questionnaire SF-36 in 87 patients with PCa. The SF-36 was completed before RT (baseline), at start of RT, at end of RT and 1...

  15. Optical Coherence Tomography for Retinal Surgery: Perioperative Analysis to Real-Time Four-Dimensional Image-Guided Surgery

    Science.gov (United States)

    Carrasco-Zevallos, Oscar M.; Keller, Brenton; Viehland, Christian; Shen, Liangbo; Seider, Michael I.; Izatt, Joseph A.; Toth, Cynthia A.

    2016-01-01

    Magnification of the surgical field using the operating microscope facilitated profound innovations in retinal surgery in the 1970s, such as pars plana vitrectomy. Although surgical instrumentation and illumination techniques are continually developing, the operating microscope for vitreoretinal procedures has remained essentially unchanged and currently limits the surgeon's depth perception and assessment of subtle microanatomy. Optical coherence tomography (OCT) has revolutionized clinical management of retinal pathology, and its introduction into the operating suite may have a similar impact on surgical visualization and treatment. In this article, we review the evolution of OCT for retinal surgery, from perioperative analysis to live volumetric (four-dimensional, 4D) image-guided surgery. We begin by briefly addressing the benefits and limitations of the operating microscope, the progression of OCT technology, and OCT applications in clinical/perioperative retinal imaging. Next, we review intraoperative OCT (iOCT) applications using handheld probes during surgical pauses, two-dimensional (2D) microscope-integrated OCT (MIOCT) of live surgery, and volumetric MIOCT of live surgery. The iOCT discussion focuses on technological advancements, applications during human retinal surgery, translational difficulties and limitations, and future directions. PMID:27409495

  16. Four-dimensional, multiphase, steady-state imaging with contrast enhancement (MUSIC) in the heart: a feasibility study in children.

    Science.gov (United States)

    Han, Fei; Rapacchi, Stanislas; Khan, Sarah; Ayad, Ihab; Salusky, Isidro; Gabriel, Simon; Plotnik, Adam; Finn, J Paul; Hu, Peng

    2015-10-01

    To develop a technique for high resolution, four-dimensional (4D), multiphase, steady-state imaging with contrast enhancement (MUSIC) in children with complex congenital heart disease. Eight pediatric patients underwent cardiovascular MRI with controlled mechanical ventilation after ferumoxytol administration. Breath-held contrast-enhanced MRA (CE-MRA) was performed during the first-pass and delayed phases of ferumoxytol, followed by a respiratory gated, 4D MUSIC acquisition during the steady state distribution phase of ferumoxytol. The subjective image quality and image sharpness were evaluated. Assessment of ventricular volumes based on 4D MUSIC was compared with those based on multislice 2D cardiac cine MRI. The 4D MUSIC technique provided cardiac-phase-resolved (65-95 ms temporal resolution) and higher spatial resolution (0.6-0.9 mm isotropic) images than previously achievable using first-pass CE-MRA or 2D cardiac cine. When compared with Ferumoxytol-based first-pass CE-MRA, the 4D MUSIC provided sharper images and better definition of the coronary arteries, aortic root, myocardium, and pulmonary trunk (P 0.95). The 4D MUSIC technique may represent a new paradigm in MR evaluation of cardiovascular anatomy and function in children with complex congenital heart disease. © 2014 Wiley Periodicals, Inc.

  17. Four-dimensional (4D) flow of the whole heart and great vessels using real-time respiratory self-gating

    DEFF Research Database (Denmark)

    Uribe, Sergio; Beerbaum, Philipp; Sørensen, Thomas Sangild

    2009-01-01

    Four-dimensional (4D) flow imaging has been used to study flow patterns and pathophysiology, usually focused on specific thoracic vessels and cardiac chambers. Whole-heart 4D flow at high measurement accuracy covering the entire thoracic cardiovascular system would be desirable to simplify...... and improve hemodynamic assessment. This has been a challenge because compensation of respiratory motion is difficult to achieve, but it is paramount to limit artifacts and improve accuracy. In this work we propose a self-gating technique for respiratory motion-compensation integrated into a whole-heart 4D...

  18. Real-time four-dimensional imaging of the heart with multi-detector row CT.

    Science.gov (United States)

    Saito, Kimiaki; Saito, Motoaki; Komatu, Shuhei; Ohtomo, Kuni

    2003-01-01

    An interactive four-dimensional (4D) visualizing system for the heart was developed by the authors. The system realizes high-resolution three-dimensional (3D) imaging with temporal resolution in a beating heart by using eight or more data sets reconstructed from multi-detector row computed tomography (MDCT) with a retrospective electrocardiograph-gated reconstruction algorithm. The motion of heart walls, papillary muscles, septa, and valves can now be observed in 4D multiplanar reformations (MPRs), as with sonography, while coronary arteries, coronary sinuses, and cardiac veins can be analyzed during the optimal phase in 4D volume-rendering images, as with angiography. All parameters such as window width, window level, field of view, panning, tilt, thresholds, opacity, color, and segmentation function are completely interactive in 4D imaging. Two longitudinal views and one latitudinal view of a heart can be simultaneously visualized in the three relative 4D MPR views. These newly developed capabilities in viewing both 3D volume and temporal resolution data, functional data, and even multiphase data with registration add considerable diagnostic potential. The advent of this real-time 4D visualizing system has enhanced the capabilities of MDCT.

  19. Quantum Mechanics and Black Holes in Four-Dimensional String Theory

    CERN Document Server

    Ellis, Jonathan Richard; Nanopoulos, Dimitri V

    1992-01-01

    In previous papers we have shown how strings in a two-dimensional target space reconcile quantum mechanics with general relativity, thanks to an infinite set of conserved quantum numbers, ``W-hair'', associated with topological soliton-like states. In this paper we extend these arguments to four dimensions, by considering explicitly the case of string black holes with radial symmetry. The key infinite-dimensional W-symmetry is associated with the $\\frac{SU(1,1)}{U(1)}$ coset structure of the dilaton-graviton sector that is a model-independent feature of spherically symmetric four-dimensional strings. Arguments are also given that the enormous number of string {\\it discrete (topological)} states account for the maintenance of quantum coherence during the (non-thermal) stringy evaporation process, as well as quenching the large Hawking-Bekenstein entropy associated with the black hole. Defining the latter as the measure of the loss of information for an observer at infinity, who - ignoring the higher string qua...

  20. Real-Time Four-dimensional Imaging of the Heart with Multi-Detector Row CT.

    Science.gov (United States)

    Saito, Kimiaki; Saito, Motoaki; Komatu, Shuhei; Ohtomo, Kuni

    2003-01-01

    An interactive four-dimensional (4D) visualizing system for the heart was developed by the authors. The system realizes high-resolution three-dimensional (3D) imaging with temporal resolution in a beating heart by using eight or more data sets reconstructed from multi-detector row computed tomography (MDCT) with a retrospective electrocardiograph-gated reconstruction algorithm. The motion of heart walls, papillary muscles, septa, and valves can now be observed in 4D multiplanar reformations (MPRs), as with sonography, while coronary arteries, coronary sinuses, and cardiac veins can be analyzed during the optimal phase in 4D volume-rendering images, as with angiography. All parameters such as window width, window level, field of view, panning, tilt, thresholds, opacity, color, and segmentation function are completely interactive in 4D imaging. Two longitudinal views and one latitudinal view of a heart can be simultaneously visualized in the three relative 4D MPR views. These newly developed capabilities in viewing both 3D volume and temporal resolution data, functional data, and even multiphase data with registration add considerable diagnostic potential. The advent of this real-time 4D visualizing system has enhanced the capabilities of MDCT. Copyright RSNA, 2003

  1. Chiral Four-Dimensional N=1 Supersymmetric Type IIA Orientifolds from Intersecting D6-Branes

    CERN Document Server

    Cvetic, M; Uranga, Angel M; Cvetic, Mirjam; Shiu, Gary; Uranga, Angel M.

    2001-01-01

    We construct N=1 supersymmetric four-dimensional orientifolds of type IIA on T^6/(Z_2 x Z_2) with D6-branes intersecting at angles. The use of D6-branes not fully aligned with the O6-planes in the model allows for a construction of many supersymmetric models with chiral matter, including those with the Standard Model and grand unified gauge groups. We perform a search for realistic gauge sectors, and construct the first example of a supersymmetric type II orientifold with SU(3)_C x SU(2)_L x U(1)_Y gauge group and three quark-lepton families. In addition to the supersymmetric Standard Model content, the model contains right-handed neutrinos, a (chiral but anomaly-free) set of exotic multiplets, and diverse vector-like multiplets. The general class of these constructions are related to familiar type II orientifolds by small instanton transitions, which in some cases change the number of generations, as discussed in specific models. These constructions are supersymmetric only for special choices of untwisted mo...

  2. Four-dimensional reconstruction of cultural heritage sites based on photogrammetry and clustering

    Science.gov (United States)

    Voulodimos, Athanasios; Doulamis, Nikolaos; Fritsch, Dieter; Makantasis, Konstantinos; Doulamis, Anastasios; Klein, Michael

    2017-01-01

    A system designed and developed for the three-dimensional (3-D) reconstruction of cultural heritage (CH) assets is presented. Two basic approaches are presented. The first one, resulting in an "approximate" 3-D model, uses images retrieved in online multimedia collections; it employs a clustering-based technique to perform content-based filtering and eliminate outliers that significantly reduce the performance of 3-D reconstruction frameworks. The second one is based on input image data acquired through terrestrial laser scanning, as well as close range and airborne photogrammetry; it follows a sophisticated multistep strategy, which leads to a "precise" 3-D model. Furthermore, the concept of change history maps is proposed to address the computational limitations involved in four-dimensional (4-D) modeling, i.e., capturing 3-D models of a CH landmark or site at different time instances. The system also comprises a presentation viewer, which manages the display of the multifaceted CH content collected and created. The described methods have been successfully applied and evaluated in challenging real-world scenarios, including the 4-D reconstruction of the historic Market Square of the German city of Calw in the context of the 4-D-CH-World EU project.

  3. Four-dimensional CT analysis of vocal cords mobility for highly focused single vocal cord irradiation.

    Science.gov (United States)

    Osman, Sarah O S; de Boer, Hans C J; Heijmen, Ben J M; Levendag, Peter C

    2008-10-01

    To quantify respiratory motion of the vocal cords during normal respiration using 4D-CT. The final goal is to develop a technique for single vocal cord irradiation (SVCI) in early glottic carcinoma. Sparing the non-involved cord and surrounding structures has the potential to preserve voice quality and allow re-irradiation of recurrent and second primary tumors. Four-dimensional CTs of 1mm slice thickness from 10 early glottic carcinoma patients were acquired. The lateral dimensions of the air gap separating the vocal cords were measured anteriorly, at mid-level and posteriorly at each phase of the 4D-CTs. The corresponding anterior-posterior gaps were similarly measured. Cranio-caudal vocal cords movements during breathing were derived from the shifts of the arythenoids. The population-averaged mean gap size+/-the corresponding standard deviation due to breathing (SD(B)) for the lateral gaps was 5.8+/-0.7mm anteriorly, 8.7+/-0.9mm at mid-level, and 11.0+/-1.3mm posteriorly. Anterior-posterior gap values were 21.7+/-0.7mm, while cranio-caudal shift SD(B) was 0.8mm. Vocal cords breathing motions were found to be small relative to their separation. Hence, breathing motion does not seem to be a limiting factor for SVCI.

  4. A four-dimensional virtual hand brain-machine interface using active dimension selection

    Science.gov (United States)

    Rouse, Adam G.

    2016-06-01

    Objective. Brain-machine interfaces (BMI) traditionally rely on a fixed, linear transformation from neural signals to an output state-space. In this study, the assumption that a BMI must control a fixed, orthogonal basis set was challenged and a novel active dimension selection (ADS) decoder was explored. Approach. ADS utilizes a two stage decoder by using neural signals to both (i) select an active dimension being controlled and (ii) control the velocity along the selected dimension. ADS decoding was tested in a monkey using 16 single units from premotor and primary motor cortex to successfully control a virtual hand avatar to move to eight different postures. Main results. Following training with the ADS decoder to control 2, 3, and then 4 dimensions, each emulating a grasp shape of the hand, performance reached 93% correct with a bit rate of 2.4 bits s-1 for eight targets. Selection of eight targets using ADS control was more efficient, as measured by bit rate, than either full four-dimensional control or computer assisted one-dimensional control. Significance. ADS decoding allows a user to quickly and efficiently select different hand postures. This novel decoding scheme represents a potential method to reduce the complexity of high-dimension BMI control of the hand.

  5. Four-Dimensional Coded Modulation with Bit-wise Decoders for Future Optical Communications

    CERN Document Server

    Alvarado, Alex

    2014-01-01

    Coded modulation (CM) is the combination of forward error correction (FEC) and multilevel constellations. Coherent optical communication systems result in a four-dimensional (4D) signal space, which naturally leads to 4D-CM transceivers. A practically attractive design paradigm is to use a bit-wise decoder, where the detection process is (suboptimally) separated into two steps: soft-decision demapping followed by binary decoding. In this paper, bit-wise decoders are studied from an information-theoretic viewpoint. 4D constellations with up to 4096 constellation points are considered. Metrics to predict the post-FEC bit-error rate (BER) of bit-wise decoders are analyzed. The mutual information is shown to fail at predicting the post-FEC BER of bit-wise decoders and the so-called generalized mutual information is shown to be a much more robust metric. It is also shown that constellations that transmit and receive information in each polarization and quadrature independently (e.g., PM-QPSK, PM-16QAM, and PM-64QA...

  6. Solutions to Yang-Mills Equations on Four-Dimensional de Sitter Space

    Science.gov (United States)

    Ivanova, Tatiana A.; Lechtenfeld, Olaf; Popov, Alexander D.

    2017-08-01

    We consider pure SU(2) Yang-Mills theory on four-dimensional de Sitter space dS4 and construct a smooth and spatially homogeneous magnetic solution to the Yang-Mills equations. Slicing dS4 as R ×S3, via an SU(2)-equivariant ansatz, we reduce the Yang-Mills equations to ordinary matrix differential equations and further to Newtonian dynamics in a double-well potential. Its local maximum yields a Yang-Mills solution whose color-magnetic field at time τ ∈R is given by B˜a=-1/2 Ia/(R2cosh2τ ), where Ia for a =1 , 2, 3 are the SU(2) generators and R is the de Sitter radius. At any moment, this spatially homogeneous configuration has finite energy, but its action is also finite and of the value -1/2 j (j +1 )(2 j +1 )π3 in a spin-j representation. Similarly, the double-well bounce produces a family of homogeneous finite-action electric-magnetic solutions with the same energy. There is a continuum of other solutions whose energy and action extend down to zero.

  7. Simulations of four-dimensional simplicial quantum gravity as dynamical triangulation

    Energy Technology Data Exchange (ETDEWEB)

    Agishtein, M.E.; Migdal, A.A. (Program in Applied and Computational Mathematics, Fine Hall, Princeton Univ., Princeton, NJ (US))

    1992-04-20

    In this paper, Four-Dimensional Simplicial Quantum Gravity is simulated using the dynamical triangulation approach. The authors studied simplicial manifolds of spherical topology and found the critical line for the cosmological constant as a function of the gravitational one, separating the phases of opened and closed Universe. When the bare cosmological constant approaches this line from above, the four-volume grows: the authors reached about 5 {times} 10{sup 4} simplexes, which proved to be sufficient for the statistical limit of infinite volume. However, for the genuine continuum theory of gravity, the parameters of the lattice model should be further adjusted to reach the second order phase transition point, where the correlation length grows to infinity. The authors varied the gravitational constant, and they found the first order phase transition, similar to the one found in three-dimensional model, except in 4D the fluctuations are rather large at the transition point, so that this is close to the second order phase transition. The average curvature in cutoff units is large and positive in one phase (gravity), and small negative in another (antigravity). The authors studied the fractal geometry of both phases, using the heavy particle propagator to define the geodesic map, as well as with the old approach using the shortest lattice paths.

  8. The Estimation of Regional Crop Yield Using Ensemble-Based Four-Dimensional Variational Data Assimilation

    Directory of Open Access Journals (Sweden)

    Zhiwei Jiang

    2014-03-01

    Full Text Available To improve crop model performance for regional crop yield estimates, a new four-dimensional variational algorithm (POD4DVar merging the Monte Carlo and proper orthogonal decomposition techniques was introduced to develop a data assimilation strategy using the Crop Environment Resource Synthesis (CERES-Wheat model. Two winter wheat yield estimation procedures were conducted on a field plot and regional scale to test the feasibility and potential of the POD4DVar-based strategy. Winter wheat yield forecasts for the field plots showed a coefficient of determination (R2 of 0.73, a root mean square error (RMSE of 319 kg/ha, and a relative error (RE of 3.49%. An acceptable yield at the regional scale was estimated with an R2 of 0.997, RMSE of 7346 tons, and RE of 3.81%. The POD4DVar-based strategy was more accurate and efficient than the EnKF-based strategy. In addition to crop yield, other critical crop variables such as the biomass, harvest index, evapotranspiration, and soil organic carbon may also be estimated. The present study thus introduces a promising approach for operationally monitoring regional crop growth and predicting yield. Successful application of this assimilation model at regional scales must focus on uncertainties derived from the crop model, model inputs, data assimilation algorithm, and assimilated observations.

  9. Four-Dimensional Ultrafast Electron Microscopy: Insights into an Emerging Technique

    KAUST Repository

    Adhikari, Aniruddha

    2016-12-15

    Four-dimensional ultrafast electron microscopy (4D-UEM) is a novel analytical technique that aims to fulfill the long-held dream of researchers to investigate materials at extremely short spatial and temporal resolutions by integrating the excellent spatial resolution of electron microscopes with the temporal resolution of ultrafast femtosecond laser-based spectroscopy. The ingenious use of pulsed photoelectrons to probe surfaces and volumes of materials enables time-resolved snapshots of the dynamics to be captured in a way hitherto impossible by other conventional techniques. The flexibility of 4D-UEM lies in the fact that it can be used in both the scanning (S-UEM) and transmission (UEM) modes depending upon the type of electron microscope involved. While UEM can be employed to monitor elementary structural changes and phase transitions in samples using real-space mapping, diffraction, electron energy-loss spectroscopy, and tomography, S-UEM is well suited to map ultrafast dynamical events on materials surfaces in space and time. This review provides an overview of the unique features that distinguish these techniques and also illustrates the applications of both S-UEM and UEM to a multitude of problems relevant to materials science and chemistry.

  10. Randomized Clinical Trial to Assess the Efficacy of Radiotherapy in Primary Mediastinal Large B-Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Aviles, Agustin, E-mail: agustin.aviles@imss.gob.mx [Oncology Research Unit, Oncology Hospital, National Medical Center, IMSS, Mexico, D. F. (Mexico); Neri, Natividad [Department of Hematology, Oncology Hospital, National Medical Center, IMSS, Mexico, D. F. (Mexico); Fernandez, Raul [Department of Radiation Therapy, Oncology Hospital, National Medical Center, IMSS, Mexico, D. F. (Mexico); Huerta-Guzman, Judith; Nambo, Maria J. [Department of Hematology, Oncology Hospital, National Medical Center, IMSS, Mexico, D. F. (Mexico)

    2012-07-15

    Purpose: We developed a controlled clinical trial to assess the efficacy and toxicity of adjuvant-involved field radiotherapy (IFRT) in patients with primary mediastinal B-cell lymphoma that achieved complete response after the patients were treated with cyclophosphamide, doxorubicin, vincristine, prednisone, and rituximab (R-CHOP-14). Methods and Materials: Between January 2001 and June 2004, 124 consecutive patients who were in complete remission after dose dense chemotherapy and rituximab administration (R-CHOP14) were randomly assigned to received IFRT (30 Gy). Sixty-three patients received IFR, and 61 patients did not (control group). Results: The study aimed to include 182 patients in each arm but was closed prematurely because in a security analysis (June 2004), progression and early relapse were more frequent in patients that did not received IFRT. Patients were followed until March 2009, at which point actuarial curves at 10 years showed that progression free-survival was 72% in patients who received IFR and 20% in the control group (p < 0.001), overall survival was 72% and 31%, respectively (p < 0.001). Acute toxicity was mild and well tolerated. Discussion: Adjuvant radiotherapy to sites of bulky disease was the only difference to have an improvement in outcome in our patients; the use of rituximab during induction did not improve complete response rates and did affect overall survival; patients who received rituximab but not IFRT had a worse prognosis. Conclusions: The use of IFRT in patients with primary mediastinal B-cell lymphoma who achieved complete response remain as the best treatment available, even in patients that received rituximab during induction.

  11. Do Patient-reported Outcome Measures Agree with Clinical and Photographic Assessments of Normal Tissue Effects after Breast Radiotherapy? The Experience of the Standardisation of Breast Radiotherapy (START) Trials in Early Breast Cancer.

    Science.gov (United States)

    Haviland, J S; Hopwood, P; Mills, J; Sydenham, M; Bliss, J M; Yarnold, J R

    2016-06-01

    In radiotherapy trials, normal tissue effects (NTE) are important end points and it is pertinent to ask whether patient-reported outcome measures (PROMs) could replace clinical and/or photographic assessments. Data from the Standardisation of Breast Radiotherapy (START) trials are examined. NTEs in the treated breast were recorded by (i) annual clinical assessments, (ii) photographs at 2 and 5 years, (iii) PROMs at 6 months, 1, 2 and 5 years after radiotherapy. Hazard ratios for the radiotherapy schedules were compared. Measures of agreement of assessments at 2 and 5 years tested concordance. PROMs were available at 2 and/or 5 years for 1939 women, of whom 1870 had clinical and 1444 had photographic assessments. All methods were sensitive to the dose difference between schedules. Patients reported a higher prevalence for all NTE end points than clinicians or photographs (P < 0.001 for most NTEs). Concordance was generally poor; weighted kappa at 2 years ranged from 0.05 (telangiectasia) to 0.21 (shrinkage and oedema). The percentage agreement was lowest between PROMs and photographic assessments of change in breast appearance (38%). All three methods produced similar conclusions for the comparison of trial schedules, despite low concordance between the methods on an individual patient basis. Careful consideration should be given to the different contributions of the measures of NTE in future radiotherapy trials. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  12. Muon borehole detector development for use in four-dimensional tomographic density monitoring

    Science.gov (United States)

    Flygare, Joshua

    The increase of CO2 concentrations in the atmosphere and the correlated temperature rise has initiated research into methods of carbon sequestration. One promising possibility is to store CO2 in subsurface reservoirs of porous rock. After injection, the monitoring of the injected CO2 is of paramount importance because the CO2 plume, if escaped, poses health and environmental risks. Traditionally, seismic reflection methods are the chosen method of determining changes in the reservoir density due to CO2 injection, but this is expensive and not continuous. A potential and promising alternative is to use cosmic muon tomography to determine density changes in the reservoir over a period of time. The work I have completed was the development of a muon detector that will be capable of being deployed in boreholes and perform long-term tomography of the reservoir of interest. The detector has the required dimensions, an angular resolution of approximately 2 degrees, and is robust enough to survive the caustic nature of the fluids in boreholes, as well as temperature and pressure fluctuations. The detector design is based on polystyrene scintillating rods arrayed in alternating layers. The layers, as arranged, can provide four-dimensional (4D) tomographic data to detect small changes in density at depths up to approximately 2 kilometers. Geant4, a Monte Carlo simulation code, was used to develop and optimize the detector design. Additionally, I developed a method of determining the muon flux at depth, including CO2 saturation changes in subsurface reservoirs. Preliminary experiments were performed at Pacific Northwest National Laboratory. This thesis will show the simulations I performed to determine the angular resolution and background discrimination required of the detector, the experiments to determine light transport through the polystyrene scintillating rods and fibers, and the method developed to predict muon flux changes at depth expected after injection.

  13. Nutritional status of patients treated with radiotherapy as determined by subjective global assessment

    Energy Technology Data Exchange (ETDEWEB)

    Koom, Woong Sub; Keum, Ki Chang [Dept. of Radiation Oncology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Ahn, Seung Do [Dept. of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); and others

    2012-09-15

    The purpose of this prospective multi-institutional study was to evaluate the nutritional status of patients undergoing radiotherapy (RT) for treatment of head and neck, lung, or gastrointestinal cancer. A total of 1,000 patients were enrolled in this study at seven different hospitals in Seoul, Korea between October 2009 and May 2010. The nutritional status of patients after receiving 3 weeks of RT was evaluated using subjective global assessment (SGA). The nutritional status of each patient was rated as well nourished (A), moderately malnourished (B), or severely malnourished (C). The mean age of patients in this study was 59.4 {+-} 11.9 years, and the male to female ratio was 7:3. According to the SGA results, 60.8%, 34.5%, and 4.7% of patients were classified as A, B, or C, respectively. The following criteria were significantly associated with malnutrition (SGA B or C; p < 0.001): loss of subcutaneous fat or muscle wasting (odds ratio [OR], 11.473); increased metabolic demand/stress (OR, 8.688); ankle, sacral edema, or ascites (OR, 3.234); and weight loss 5% (OR, 2.299). SGA was applied successfully to assess the nutritional status of most patients. The prevalence of malnutrition in a radiation oncology department was 39.2%. The results of this study serve as a basis for implementation of nutrition intervention to patients being treated at radiation oncology departments.

  14. Nutritional status of patients treated with radiotherapy as determined by subjective global assessment

    Science.gov (United States)

    Koom, Woong Sub; Ahn, Seung Do; Song, Si Yeol; Lee, Chang Geol; Moon, Sung Ho; Chie, Eui Kyu; Jang, Hong Seok; Oh, Young-Taek; Lee, Ho Sun

    2012-01-01

    Purpose The purpose of this prospective multi-institutional study was to evaluate the nutritional status of patients undergoing radiotherapy (RT) for treatment of head and neck, lung, or gastrointestinal cancer. Materials and Methods A total of 1,000 patients were enrolled in this study at seven different hospitals in Seoul, Korea between October 2009 and May 2010. The nutritional status of patients after receiving 3 weeks of RT was evaluated using subjective global assessment (SGA). The nutritional status of each patient was rated as well nourished (A), moderately malnourished (B), or severely malnourished (C). Results The mean age of patients in this study was 59.4 ± 11.9 years, and the male to female ratio was 7:3. According to the SGA results, 60.8%, 34.5%, and 4.7% of patients were classified as A, B, or C, respectively. The following criteria were significantly associated with malnutrition (SGA B or C; p < 0.001): loss of subcutaneous fat or muscle wasting (odds ratio [OR], 11.473); increased metabolic demand/stress (OR, 8.688); ankle, sacral edema, or ascites (OR, 3.234); and weight loss ≥5% (OR, 2.299). Conclusion SGA was applied successfully to assess the nutritional status of most patients. The prevalence of malnutrition in a radiation oncology department was 39.2%. The results of this study serve as a basis for implementation of nutrition intervention to patients being treated at radiation oncology departments. PMID:23170292

  15. Four-dimensional magnetic resonance imaging for the determination of tumour movement and its evaluation using a dynamic porcine lung phantom

    Energy Technology Data Exchange (ETDEWEB)

    Remmert, G [Department of Medical Physics in Radiation Oncology, German Cancer Research Centre (DKFZ), 69120 Heidelberg (Germany); Biederer, J [Department of Radiology, German Cancer Research Centre (DKFZ), 69120 Heidelberg (Germany); Lohberger, F [Department of Medical Physics in Radiology, German Cancer Research Centre (DKFZ), 69120 Heidelberg (Germany); Fabel, M [Department of Radiology, German Cancer Research Centre (DKFZ), 69120 Heidelberg (Germany); Hartmann, G H [Department of Medical Physics in Radiation Oncology, German Cancer Research Centre (DKFZ), 69120 Heidelberg (Germany)

    2007-09-21

    A method of four-dimensional (4D) magnetic resonance imaging (MRI) has been implemented and evaluated. It consists of retrospective sorting and slice stacking of two-dimensional (2D) images using an external signal for motion monitoring of the object to be imaged. The presented method aims to determine the tumour trajectories based on a signal that is appropriate for monitoring the movement of the target volume during radiotherapy such that the radiation delivery can be adapted to the movement. For evaluation of the 4D-MRI method, it has been applied to a dynamic lung phantom, which exhibits periodic respiratory movement of a porcine heart-lung explant with artificial pulmonary nodules. Anatomic changes of the lung phantom caused by respiratory motion have been quantified, revealing hysteresis. The results demonstrate the feasibility of the presented method of 4D-MRI. In particular, it enables the determination of trajectories of periodically moving objects with an uncertainty in the order of 1 mm. (note)

  16. Optimizing global CO emission estimates using a four-dimensional variational data assimilation system and surface network observations

    NARCIS (Netherlands)

    Hooghiemstra, P.B.; Krol, M.C.; Meirink, J.F.; Bergamaschi, P.; van der Werf, G.R.; Novelli, P.C.; Aben, I.; Rockmann, T.

    2011-01-01

    We apply a four-dimensional variational (4D-VAR) data assimilation system to optimize carbon monoxide (CO) emissions for 2003 and 2004 and to reduce the uncertainty of emission estimates from individual sources using the chemistry transport model TM5. The system is designed to assimilate large

  17. Risk assessment methods in radiotherapy: Probabilistic safety assessment (PSA); Los metodos de analisis de riesgo en radioterapia: Analisis Probabilistico de seguridad (APS)

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Vera, M. L.; Perez Mulas, A.; Delgado, J. M.; Barrientos Ontero, M.; Somoano, F.; Alvarez Garcia, C.; Rodriguez Marti, M.

    2011-07-01

    The understanding of accidents that have occurred in radiotherapy and the lessons learned from them are very useful to prevent repetition, but there are other risks that have not been detected to date. With a view to identifying and preventing such risks, proactive methods successfully applied in other fields, such as probabilistic safety assessment (PSA), have been developed. (Author)

  18. Objective assessment in digital images of skin erythema caused by radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Matsubara, H., E-mail: matubara@nirs.go.jp; Matsufuji, N.; Tsuji, H.; Yamamoto, N.; Karasawa, K.; Nakajima, M.; Karube, M. [National Institute of Radiological Sciences (NIRS), Chiba 263-8555 (Japan); Takahashi, W. [Department of Radiology, University of Tokyo Hospital, Tokyo 113-8655 (Japan)

    2015-09-15

    Purpose: Skin toxicity caused by radiotherapy has been visually classified into discrete grades. The present study proposes an objective and continuous assessment method of skin erythema in digital images taken under arbitrary lighting conditions, which is the case for most clinical environments. The purpose of this paper is to show the feasibility of the proposed method. Methods: Clinical data were gathered from six patients who received carbon beam therapy for lung cancer. Skin condition was recorded using an ordinary compact digital camera under unfixed lighting conditions; a laser Doppler flowmeter was used to measure blood flow in the skin. The photos and measurements were taken at 3 h, 30, and 90 days after irradiation. Images were decomposed into hemoglobin and melanin colors using independent component analysis. Pixel values in hemoglobin color images were compared with skin dose and skin blood flow. The uncertainty of the practical photographic method was also studied in nonclinical experiments. Results: The clinical data showed good linearity between skin dose, skin blood flow, and pixel value in the hemoglobin color images; their correlation coefficients were larger than 0.7. It was deduced from the nonclinical that the uncertainty due to the proposed method with photography was 15%; such an uncertainty was not critical for assessment of skin erythema in practical use. Conclusions: Feasibility of the proposed method for assessment of skin erythema using digital images was demonstrated. The numerical relationship obtained helped to predict skin erythema by artificial processing of skin images. Although the proposed method using photographs taken under unfixed lighting conditions increased the uncertainty of skin information in the images, it was shown to be powerful for the assessment of skin conditions because of its flexibility and adaptability.

  19. Assessment of renal function after conformal radiotherapy and intensity-modulated radiotherapy by functional {sup 1}H-MRI and {sup 23}Na-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Haneder, S.; Michaely, H.J.; Schoenberg, S.O. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Inst. of Clinical Radiology and Nuclear Medicine; Konstandin, S.; Schad, L.R. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Computer-Assisted Clinical Medicine; Siebenlist, K.; Wertz, H.; Wenz, F.; Lohr, F.; Boda-Heggemann, J. [Universitaetsmedizin Mannheim, Heidelberg Univ., Mannheim (Germany). Dept. of Radiation Oncology

    2012-12-15

    Purpose: Adjuvant radiochemotherapy (RCHT) improves survival of patients with locally advanced gastric cancer. Conventional three-dimensional conformal radiotherapy (3D-CRT) results in ablative doses to a significant amount of the left kidney, while image-guided intensity-modulated radiotherapy (IG-IMRT) provides excellent target coverage with improved kidney sparing. Few long-term results on IMRT for gastric cancer, however, have been published. Functional magnetic resonance imaging (fMRI) at 3.0 T including blood oxygenation-level dependent (BOLD) imaging, diffusion-weighted imaging (DWI) and, for the first time, {sup 23}Na imaging was used to evaluate renal status after radiotherapy with 3D-CRT or IG-IMRT. Patients and methods Four disease-free patients (2 after 3D-CRT and 2 after IMRT; FU for all patients > 5 years) were included in this feasibility study. Morphological sequences, axial DWI images, 2D-gradient echo (GRE)-BOLD images, and {sup 23}Na images were acquired. Mean values/standard deviations for ({sup 23}Na), the apparent diffusion coefficient (ADC), and R2{sup *} values were calculated for the upper/middle/lower parts of both kidneys. Corticomedullary {sup 23}Na-concentration gradients were determined. Results: Surprisingly, IG-IMRT patients showed no morphological alterations and no statistically significant differences of ADC and R2{sup *} values in all renal parts. Values for mean corticomedullary {sup 23}Na-concentration matched those for healthy volunteers. Results were similar in 3D-CRT patients, except for the cranial part of the left kidney. This was atrophic and presented significantly reduced functional parameters (p = 0.001 - p = 0.033). Reduced ADC values indicated reduced cell density and reduced extracellular space. Cortical and medullary R2{sup *} values of the left cranial kidney in the 3D-CRT group were higher, indicating more deoxygenated hemoglobin due to reduced blood flow/oxygenation. ({sup 23}Na) of the renal cranial parts in

  20. Tumor shrinkage assessed by volumetric MRI in the long-term follow-up after stereotactic radiotherapy of meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Astner, Sabrina T.; Theodorou, Marilena; Dobrei-Ciuchendea, Mihaela; Kopp, Christine; Molls, Michael [Dept. of Radiotherapy and Radiooncology, Klinikum rechts der Isar, Technical Univ. of Munich (Germany); Auer, Florian [Dept. of Neuroradiology, Klinikum rechts der Isar, Technical Univ. of Munich (Germany); Grosu, Anca-Ligia [Dept. of Radiotherapy, Univ. Hospital Freiburg (Germany)

    2010-08-15

    Purpose: To evaluate tumor volume reduction in the follow-up of meningiomas after fractionated stereotactic radiotherapy (FSRT) or linac radiosurgery (RS) by using magnetic resonance imaging (MRI). Patients and Methods: In 59 patients with skull base meningiomas, gross tumor volume (GTV) was outlined on contrast-en-hanced MRI before and median 50 months (range 11-92 months) after stereotactic radiotherapy. MRI was performed as an axial three-dimensional gradient-echo T1-weighted sequence at 1.6 mm slice thickness without gap (3D-MRI). Results were compared to the reports of diagnostic findings. Results: Mean tumor size of all 59 meningiomas was 13.9 ml (0.8-62.9 ml) before treatment. There was shrinkage of the treated meningiomas in all but one patient. Within a median volumetric follow-up of 50 months (11-95 months), an absolute mean volume reduction of 4 ml (0-18 ml) was seen. The mean relative size reduction compared to the volume before radiotherapy was 27% (0-73%). Shrinkage measured by 3D-MRI was greater at longer time intervals after radiotherapy. The mean size reduction was 17%, 23%, and 30% (at < 24 months, 24-48 months, and 48-72 months). Conclusion: By using 3D-MRI in almost all patients undergoing radiotherapy of a meningioma, tumor shrinkage is detected. The data presented here demonstrate that volumetric assessment from 3D-MRI provides additional information to routinely used radiologic response measurements. After FSRT or RS, a mean size reduction of 25-45% can be expected within 4 years. (orig.)

  1. GPU-based four-dimensional general-relativistic ray tracing

    Science.gov (United States)

    Kuchelmeister, Daniel; Müller, Thomas; Ament, Marco; Wunner, Günter; Weiskopf, Daniel

    2012-10-01

    This paper presents a new general-relativistic ray tracer that enables image synthesis on an interactive basis by exploiting the performance of graphics processing units (GPUs). The application is capable of visualizing the distortion of the stellar background as well as trajectories of moving astronomical objects orbiting a compact mass. Its source code includes metric definitions for the Schwarzschild and Kerr spacetimes that can be easily extended to other metric definitions, relying on its object-oriented design. The basic functionality features a scene description interface based on the scripting language Lua, real-time image output, and the ability to edit almost every parameter at runtime. The ray tracing code itself is implemented for parallel execution on the GPU using NVidia's Compute Unified Device Architecture (CUDA), which leads to performance improvement of an order of magnitude compared to a single CPU and makes the application competitive with small CPU cluster architectures. Program summary Program title: GpuRay4D Catalog identifier: AEMV_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEMV_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 73649 No. of bytes in distributed program, including test data, etc.: 1334251 Distribution format: tar.gz Programming language: C++, CUDA. Computer: Linux platforms with a NVidia CUDA enabled GPU (Compute Capability 1.3 or higher), C++ compiler, NVCC (The CUDA Compiler Driver). Operating system: Linux. RAM: 2 GB Classification: 1.5. External routines: OpenGL Utility Toolkit development files, NVidia CUDA Toolkit 3.2, Lua5.2 Nature of problem: Ray tracing in four-dimensional Lorentzian spacetimes. Solution method: Numerical integration of light rays, GPU-based parallel programming using CUDA, 3D

  2. An update in symptom clusters using the Edmonton Symptom Assessment System in a palliative radiotherapy clinic.

    Science.gov (United States)

    Ganesh, Vithusha; Zhang, Liying; Chan, Stephanie; Wan, Bo Angela; Drost, Leah; Tsao, May; Danjoux, Cyril; Barnes, Elizabeth; McDonald, Rachel; Rowbottom, Leigha; Zaki, Pearl; Chow, Ronald; Hwang, Matthew K; DeAngelis, Carlo; Lao, Nicholas; Chow, Edward

    2017-11-01

    To identify symptom clusters in advanced cancer patients attending a palliative radiotherapy clinic using the Edmonton Symptom Assessment System (ESAS). Principal component analysis (PCA), exploratory factor analysis (EFA), and hierarchical cluster analysis (HCA) were used to identify symptom clusters among the nine ESAS items using scores from each patient's first visit. ESAS scores from 182 patients were analyzed. The PCA identified three symptom clusters (cluster 1: depression-anxiety-well-being, cluster 2: pain-tiredness-drowsiness, cluster 3: nausea-dyspnea-loss of appetite). The EFA identified two clusters (cluster 1: tiredness-drowsiness-loss of appetite-well-being-pain-nausea-dyspnea, cluster 2: depression-anxiety). The HCA identified three clusters similar to the PCA with an exception of the loss of appetite item being classified under cluster 1 rather than 3. Two to three symptom clusters were identified using three analytical methods, with similar patterns reported in the literature. Particular groups of items co-occurred consistently across all three analyses: depression and anxiety; nausea and dyspnea; as well as pain, tiredness, and drowsiness. Three similar symptom clusters were identified in our patient population using the PCA and HCA; whereas, the EFA produced two clusters: one physical and one psychological cluster. Given the implications of symptom clusters in the management of quality of life, clinicians should be aware of these clusters to aid in the palliative treatment of patients.

  3. Four-dimensional cone beam CT reconstruction and enhancement using a temporal nonlocal means method

    Energy Technology Data Exchange (ETDEWEB)

    Jia Xun; Tian Zhen; Lou Yifei; Sonke, Jan-Jakob; Jiang, Steve B. [Center for Advanced Radiotherapy Technologies and Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California 92037 (United States); School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318 (United States); Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Center for Advanced Radiotherapy Technologies and Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California 92037 (United States)

    2012-09-15

    Purpose: Four-dimensional cone beam computed tomography (4D-CBCT) has been developed to provide respiratory phase-resolved volumetric imaging in image guided radiation therapy. Conventionally, it is reconstructed by first sorting the x-ray projections into multiple respiratory phase bins according to a breathing signal extracted either from the projection images or some external surrogates, and then reconstructing a 3D CBCT image in each phase bin independently using FDK algorithm. This method requires adequate number of projections for each phase, which can be achieved using a low gantry rotation or multiple gantry rotations. Inadequate number of projections in each phase bin results in low quality 4D-CBCT images with obvious streaking artifacts. 4D-CBCT images at different breathing phases share a lot of redundant information, because they represent the same anatomy captured at slightly different temporal points. Taking this redundancy along the temporal dimension into account can in principle facilitate the reconstruction in the situation of inadequate number of projection images. In this work, the authors propose two novel 4D-CBCT algorithms: an iterative reconstruction algorithm and an enhancement algorithm, utilizing a temporal nonlocal means (TNLM) method. Methods: The authors define a TNLM energy term for a given set of 4D-CBCT images. Minimization of this term favors those 4D-CBCT images such that any anatomical features at one spatial point at one phase can be found in a nearby spatial point at neighboring phases. 4D-CBCT reconstruction is achieved by minimizing a total energy containing a data fidelity term and the TNLM energy term. As for the image enhancement, 4D-CBCT images generated by the FDK algorithm are enhanced by minimizing the TNLM function while keeping the enhanced images close to the FDK results. A forward-backward splitting algorithm and a Gauss-Jacobi iteration method are employed to solve the problems. The algorithms implementation on

  4. T2-weighted four dimensional magnetic resonance imaging with result-driven phase sorting

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yilin; Yin, Fang-Fang; Cai, Jing, E-mail: jing.cai@duke.edu [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 and Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Czito, Brian G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Bashir, Mustafa R. [Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2015-08-15

    Purpose: T2-weighted MRI provides excellent tumor-to-tissue contrast for target volume delineation in radiation therapy treatment planning. This study aims at developing a novel T2-weighted retrospective four dimensional magnetic resonance imaging (4D-MRI) phase sorting technique for imaging organ/tumor respiratory motion. Methods: A 2D fast T2-weighted half-Fourier acquisition single-shot turbo spin-echo MR sequence was used for image acquisition of 4D-MRI, with a frame rate of 2–3 frames/s. Respiratory motion was measured using an external breathing monitoring device. A phase sorting method was developed to sort the images by their corresponding respiratory phases. Besides, a result-driven strategy was applied to effectively utilize redundant images in the case when multiple images were allocated to a bin. This strategy, selecting the image with minimal amplitude error, will generate the most representative 4D-MRI. Since we are using a different image acquisition mode for 4D imaging (the sequential image acquisition scheme) with the conventionally used cine or helical image acquisition scheme, the 4D dataset sufficient condition was not obviously and directly predictable. An important challenge of the proposed technique was to determine the number of repeated scans (N{sub R}) required to obtain sufficient phase information at each slice position. To tackle this challenge, the authors first conducted computer simulations using real-time position management respiratory signals of the 29 cancer patients under an IRB-approved retrospective study to derive the relationships between N{sub R} and the following factors: number of slices (N{sub S}), number of 4D-MRI respiratory bins (N{sub B}), and starting phase at image acquisition (P{sub 0}). To validate the authors’ technique, 4D-MRI acquisition and reconstruction were simulated on a 4D digital extended cardiac-torso (XCAT) human phantom using simulation derived parameters. Twelve healthy volunteers were involved

  5. Development of an MM5-Based Four Dimensional Variational Analysis System for Distributed Memory Multiprocessor Computers

    Science.gov (United States)

    Nehrkorn, T.; Modica, G. D.; Cerniglia, M.; Ruggiero, F. H.; Michalakes, J. G.; Zou, X.

    2001-05-01

    The MM5 four-dimensional variational analysis system (4DVAR) is being updated to allow its efficient execution on parallel distributed memory computers. The previous version of the MM5 4DVAR system (Zou et al. 1998 [3]) is coded for single processor computer architectures and its nonlinear, tangent-linear, and adjoint components are based on version 1 of the MM5. In order to take advantage of the parallelization mechanisms (Michalakes 2000 [2]) already in place for the latest release (Version 3.4) of the MM5 nonlinear model (NLM), the existing (Version 1) tangent linear (TLM) and adjoint model codes are also being updated to Version 3.4. We are using the Tangent Linear and Adjoint Model Compiler (TAMC; Giering and Kaminski 1988 [1]) in this process. The TAMC is a source-to-source translator that generates Fortran code for the TLM or adjoint from the Fortran code of the NLM. While it would be possible to incorporate the TAMC as part of a pre-compilation process--thus requiring the maintenance of the NLM code only--this would require that the NLM code first be modified as needed to result in the correct TLM and adjoint code output by TAMC. For the development of the MM5 adjoint, we have chosen instead to use TAMC as a development tool only, and separately maintain the TLM and adjoint versions of the model code. This approach makes it possible to minimize changes to the MM5 code as supported by NCAR. The TLM and adjoint are tested for correctness, using the standard comparison of the TLM and finite difference gradients to check for correctness of the former, and the definition of the adjoint to check for consistency of the TLM and adjoint. This testing is performed for individual subroutines (unit testing) as well as the complete model integration (unit integration testing), with objective functions designed to test different parts of the model state vector. Testing can be done for the entire model domain, or for selected model grid points. Finally, the TLM and

  6. A construction of a large family of commuting pairs of integrable symplectic birational four-dimensional maps.

    Science.gov (United States)

    Petrera, Matteo; Suris, Yuri B

    2017-02-01

    We give a construction of completely integrable four-dimensional Hamiltonian systems with cubic Hamilton functions. Applying to the corresponding pairs of commuting quadratic Hamiltonian vector fields the so called Kahan-Hirota-Kimura discretization scheme, we arrive at pairs of birational four-dimensional maps. We show that these maps are symplectic with respect to a symplectic structure that is a perturbation of the standard symplectic structure on [Formula: see text], and possess two independent integrals of motion, which are perturbations of the original Hamilton functions and which are in involution with respect to the perturbed symplectic structure. Thus, these maps are completely integrable in the Liouville-Arnold sense. Moreover, under a suitable normalization of the original pairs of vector fields, the pairs of maps commute and share the invariant symplectic structure and the two integrals of motion.

  7. Four-dimensional optical multiband-OFDM for beyond 1.4 Tb/s serial optical transmission.

    Science.gov (United States)

    Djordjevic, Ivan; Batshon, Hussam G; Xu, Lei; Wang, Ting

    2011-01-17

    We propose a four-dimensional (4D) coded multiband-OFDM scheme suitable for beyond 1.4 Tb/s serial optical transport. The proposed scheme organizes the N-dimensional (ND) signal constellation points in the form of signal matrix; employs 2D-inverse FFT and 2D-FFT to perform modulation and demodulation, respectively; and exploits both orthogonal polarizations. This scheme can fully exploit advantages of OFDM to deal with chromatic dispersion, PMD and PDL effects; and multidimensional signal constellations to improve OSNR sensitivity of conventional optical OFDM. The improvement of 4D-OFDM over corresponding polarization-multiplexed QAM (with the same number of constellation points) ranges from 1.79 dB for 16 signal constellation point-four-dimensional-OFDM (16-4D-OFDM) up to 4.53 dB for 128-4D-OFDM.

  8. The Abelian projection versus the Hitchin fibration of K(D) pairs in four-dimensional QCD

    OpenAIRE

    Bochicchio, Marco

    1999-01-01

    We point out that the concept of Abelian projection gives us a physical interpretation of the role that the Hitchin fibration of parabolic K(D) pairs plays in the large-N limit of four-dimensional QCD. This physical interpretation furnishes also a simple criterium for the confinement of electric fluxes in the large-N limit of QCD. There is also an alternative, compatible interpretation, based on the QCD string.

  9. High-Performance Computing and Four-Dimensional Data Assimilation: The Impact on Future and Current Problems

    Science.gov (United States)

    Makivic, Miloje S.

    1996-01-01

    This is the final technical report for the project entitled: "High-Performance Computing and Four-Dimensional Data Assimilation: The Impact on Future and Current Problems", funded at NPAC by the DAO at NASA/GSFC. First, the motivation for the project is given in the introductory section, followed by the executive summary of major accomplishments and the list of project-related publications. Detailed analysis and description of research results is given in subsequent chapters and in the Appendix.

  10. Improving thoracic four-dimensional cone-beam CT reconstruction with anatomical-adaptive image regularization (AAIR)

    OpenAIRE

    Shieh, Chun-Chien; Kipritidis, John; O’Brien, Ricky T.; Cooper, Benjamin J.; Kuncic, Zdenka; Keall, Paul J

    2015-01-01

    Total-variation (TV) minimization reconstructions can significantly reduce noise and streaks in thoracic four-dimensional cone-beam computed tomography (4D CBCT) images compared to the Feldkamp-Davis-Kress (FDK) algorithm currently used in practice. TV minimization reconstructions are, however, prone to over-smoothing anatomical details and are also computationally inefficient. The aim of this study is to demonstrate a proof of concept that these disadvantages can be overcome by incorporating...

  11. Four-dimensional visualization of subpleural alveolar dynamics in vivo during uninterrupted mechanical ventilation of living swine.

    Science.gov (United States)

    Namati, Eman; Warger, William C; Unglert, Carolin I; Eckert, Jocelyn E; Hostens, Jeroen; Bouma, Brett E; Tearney, Guillermo J

    2013-01-01

    Pulmonary alveoli have been studied for many years, yet no unifying hypothesis exists for their dynamic mechanics during respiration due to their miniature size (100-300 μm dimater in humans) and constant motion, which prevent standard imaging techniques from visualizing four-dimensional dynamics of individual alveoli in vivo. Here we report a new platform to image the first layer of air-filled subpleural alveoli through the use of a lightweight optical frequency domain imaging (OFDI) probe that can be placed upon the pleura to move with the lung over the complete range of respiratory motion. This device enables in-vivo acquisition of four-dimensional microscopic images of alveolar airspaces (alveoli and ducts), within the same field of view, during continuous ventilation without restricting the motion or modifying the structure of the alveoli. Results from an exploratory study including three live swine suggest that subpleural alveolar air spaces are best fit with a uniform expansion (r (2) = 0.98) over a recruitment model (r (2) = 0.72). Simultaneously, however, the percentage change in volume shows heterogeneous alveolar expansion within just a 1 mm x 1 mm field of view. These results signify the importance of four-dimensional imaging tools, such as the device presented here. Quantification of the dynamic response of the lung during ventilation may help create more accurate modeling techniques and move toward a more complete understanding of alveolar mechanics.

  12. Effect of tumor volume on the enhancement pattern of parathyroid adenoma on parathyroid four-dimensional CT

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Kyoung [Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Dongguk University Ilsan Hospital, Department of Radiology, Goyang-si (Korea, Republic of); Yun, Tae Jin; Kim, Ji-hoon; Kang, Koung Mi; Choi, Seung Hong; Sohn, Chul-Ho [Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University Hospital, Department of Radiology, Jongno-gu, Seoul (Korea, Republic of); Lee, Kyu Eun; Kim, Su-jin [Seoul National University Hospital, Department of Surgery, Seoul (Korea, Republic of); Won, Jae-Kyung [Seoul National University Hospital, Department of Pathology, Seoul (Korea, Republic of)

    2016-05-15

    The purpose of this study is to assess the effect of tumor volume on the enhancement pattern of parathyroid adenoma (PTA) on four-dimensional computed tomography (4D-CT). We analyzed the enhancement patterns of PTA on four-phase 4D-CT in 44 patients. Dependency of the changes of Hounsfield unit values (ΔHU) on the tumor volumes and clinical characteristics was evaluated using linear regression analyses. In addition, an unpaired t test was used to compare ΔHU of PTAs between PTA volume ≥1 cm{sup 3} and <1 cm{sup 3}, thyroid gland, and lymph node. PTA volume based on CT was the strongest factor on the ΔHU{sub Pre} {sub to} {sub Arterial} and ΔHU{sub Arterial} {sub to} {sub Venous} and ΔHU{sub Arterial} {sub to} {sub Delayed} (R {sup 2} = 0.34, 0.25, and 0.32, respectively, P < 0.001 for both). PTA ≥1 cm {sup 3} had statistically significant greater enhancement between the unenhanced phase and the arterial phase than PTA <1 cm {sup 3} (mean values ± standard deviations (SDs) of ΔHU{sub Pre} {sub to} {sub Arterial}, 102.7 ± 33.7 and 57.5 ± 28.8, respectively, P < 0.001). PTA ≥1 cm {sup 3} showed an early washout pattern on the venous phase, whereas PTA <1 cm {sup 3} showed a progressive enhancement pattern on the venous phase (mean values ± SDs of ΔHU{sub Arterial} {sub to} {sub Venous}, -13.2 ± 31.6 and 14.4 ± 32.7, respectively; P = 0.009). The enhancement pattern of PTA on 4D-CT is variable with respect to PTA volume based on CT. Therefore, the enhancement pattern of PTA on 4D-CT requires careful interpretation concerning the tumor volume, especially in cases of PTA <1 cm {sup 3}. (orig.)

  13. Assessment of Olfactory Threshold in Patients Undergoing Radiotherapy for Head and Neck Malignancies

    Directory of Open Access Journals (Sweden)

    Mir Mohammad Jalali

    2014-10-01

    Conclusion:  Deterioration in olfactory threshold scores was found at 6 months after initiation of radiation therapy. Provided that these results are reproducible, an evaluation of olfactory functioning in patients with head and neck malignancies using in vivo dosimetry may be useful for determining the optimal dose for patients treated with conformal radiotherapy techniques while avoiding the side effects of radiation.

  14. Cerebral arteriovenous malformation: Spetzler-Martin classification at subsecond-temporal-resolution four-dimensional MR angiography compared with that at DSA.

    Science.gov (United States)

    Hadizadeh, Dariusch R; von Falkenhausen, Marcus; Gieseke, Jürgen; Meyer, Bernhard; Urbach, Horst; Hoogeveen, Romhild; Schild, Hans H; Willinek, Winfried A

    2008-01-01

    To prospectively test the hypothesis that subsecond-temporal-resolution four-dimensional (4D) contrast material-enhanced magnetic resonance (MR) angiography at 3.0 T enables the same Spetzler-Martin classification (nidus size, venous drainage, eloquence) of cerebral arteriovenous malformation (AVM) as that at digital subtraction angiography (DSA). Institutional ethics committee approval and written informed consent were obtained. In a prospective intraindividual comparative study, 18 consecutive patients with cerebral AVM (nine men, nine women; mean age, 41.9 years +/- 14.0 [standard deviation]; range, 23-69 years) were examined with 4D contrast-enhanced MR angiography and DSA. Four-dimensional contrast-enhanced MR angiography combined randomly segmented central k-space ordering, keyhole imaging, sensitivity encoding, and half-Fourier imaging, which yielded a total acceleration factor of 60. Fifty dynamic scans were obtained every 608 msec at an acquired spatial resolution of 1.1 x 1.4 x 1.1 mm. Four-dimensional contrast-enhanced MR angiograms were independently reviewed by one neuroradiologist and one neurosurgeon according to Spetzler-Martin classification, overall diagnostic quality, and level of confidence. Kendall W coefficients of concordance (K) were computed to compare reader assessment of image quality, level of confidence, and Spetzler-Martin classification by using 4D contrast-enhanced MR angiography and to compare Spetzler-Martin classification as determined with DSA with that at 4D contrast-enhanced MR angiography. Spetzler-Martin classification of cerebral AVM at 4D contrast-enhanced MR angiography and at DSA matched in 18 of 18 patients for both readers, which yielded 100% interobserver agreement (K = 1). Image quality of 4D contrast-enhanced MR angiography was judged to be at least adequate for diagnosis in all patients by both readers. In three of 18 patients, DSA depicted additional arterial feeders of cerebral AVM. Subsecond-temporal-resolution 4

  15. An assessment of PTV margin based on actual accumulated dose for prostate cancer radiotherapy.

    Science.gov (United States)

    Wen, Ning; Kumarasiri, Akila; Nurushev, Teamour; Burmeister, Jay; Xing, Lei; Liu, Dezhi; Glide-Hurst, Carri; Kim, Jinkoo; Zhong, Hualiang; Movsas, Benjamin; Chetty, Indrin J

    2013-11-07

    The purpose of this work is to present the results of a margin reduction study involving dosimetric and radiobiologic assessment of cumulative dose distributions, computed using an image guided adaptive radiotherapy based framework. Eight prostate cancer patients, treated with 7-9, 6 MV, intensity modulated radiation therapy (IMRT) fields, were included in this study. The workflow consists of cone beam CT (CBCT) based localization, deformable image registration of the CBCT to simulation CT image datasets (SIM-CT), dose reconstruction and dose accumulation on the SIM-CT, and plan evaluation using radiobiological models. For each patient, three IMRT plans were generated with different margins applied to the CTV. The PTV margin for the original plan was 10 mm and 6 mm at the prostate/anterior rectal wall interface (10/6 mm) and was reduced to: (a) 5/3 mm, and (b) 3 mm uniformly. The average percent reductions in predicted tumor control probability (TCP) in the accumulated (actual) plans in comparison to the original plans over eight patients were 0.4%, 0.7% and 11.0% with 10/6 mm, 5/3 mm and 3 mm uniform margin respectively. The mean increase in predicted normal tissue complication probability (NTCP) for grades 2/3 rectal bleeding for the actual plans in comparison to the static plans with margins of 10/6, 5/3 and 3 mm uniformly was 3.5%, 2.8% and 2.4% respectively. For the actual dose distributions, predicted NTCP for late rectal bleeding was reduced by 3.6% on average when the margin was reduced from 10/6 mm to 5/3 mm, and further reduced by 1.0% on average when the margin was reduced to 3 mm. The average reduction in complication free tumor control probability (P+) in the actual plans in comparison to the original plans with margins of 10/6, 5/3 and 3 mm was 3.7%, 2.4% and 13.6% correspondingly. The significant reduction of TCP and P+ in the actual plan with 3 mm margin came from one outlier, where individualizing patient treatment plans through

  16. Epworth Sleepiness Scale- a novel tool to assess somnolence syndrome in patients receiving radiotherapy to the brain

    Directory of Open Access Journals (Sweden)

    Ritika Rajkumar Harjani

    2015-03-01

    Full Text Available Purpose: Radiation to brain causes early, early-delayed, and delayed side effects. There is paucity of literature regarding early-delayed effects like somnolence syndrome. Existing studies use general symptom assessment and visual analog scales. Epworth Sleepiness Scale (ESS is a time tested tool to assess daytime sleepiness in various conditions. In this study, the ESS has been used to determine the occurrence of somnolence in patients receiving cranial radiotherapy for primary and metastatic brain tumors. Thus the ESS has been used in a novel setting in our study. The ESS is a simple to administer questionnaire and may be useful in grading the severity of somnolence. To our knowledge, this is the second study to determine post radiation somnolence using ESS. Methods: This prospective study was conducted in 23 patients with primary and metastatic brain tumor. Patient demographics and tumor type and grade was noted. Those with Karnofsky Performance Scale (KPS less than 70 and with pre-existing sleep disorders were excluded. Radiotherapy regimen included palliative whole brain radiation for brain metastases and conformal adjuvant radiotherapy for primary brain tumors as per standard guidelines. All subjects included were administered ESS at baseline and weekly thereafter during and for 6 weeks after radiation. Results: All 23 patients (median age 50 years completed the planned questionnaires until 6 weeks post radiation. Twenty (87% patients had primary brain tumors whereas three (13% patients had metastatic lesions in brain. Of the 23 patients, 14 patients (60.86% had abnormal or increased daytime sleepiness; of which 3 had ESS scores greater than 16. Conclusion: Somnolence was noted in 60.86% of the patients, which is in accordance with existing literature. Epworth sleepiness scale is an effective tool to detect and quantify somnolence, However, it does not consider other symptoms of somnolence syndrome and hence should be combined with visual

  17. Late oral mucosa alterations after radiotherapy for head and neck cancer assessed by exfoliative cytology.

    Science.gov (United States)

    Massaro, Patrizia; Corbella, Franco; DI Liberto, Riccardo; Paolini, Alessandro; Pasi, Francesca; Tinelli, Carmine; DE Silvestri, Annalisa; Nano, Rosanna

    2014-02-01

    Late oral mucosa changes after radiotherapy for head and neck cancer have been poorly studied. This study aimed to determine long-term effects of radiotherapy on oral mucosa using exfoliative oral cytology. Fifty patients with cancer were enrolled, five of whom in order to validate microscopic analysis. Smears were collected at programmed visit; a score was used to rank possible cytological alterations. Presence of inflammation was also microscopically described and compared to blood count tests. Epithelial cells revealed a peculiar 'folding' phenotype, not related to chemotherapy, total dose, or to the effective dose delivered to mucosa. Inflammation described was related to the score for 'folding' cells; moreover, score decreased in the presence of a higher lymphocyte count, while it was not altered by neutrophil count. We suggest application of exfoliative cytology to study radiation injury and the variability of individual response of oral mucosa to radiation.

  18. Uniform framework for the objective assessment and optimisation of radiotherapy image quality

    OpenAIRE

    Reilly, Andrew James

    2011-01-01

    Image guidance has rapidly become central to current radiotherapy practice. A uniform framework is developed for evaluating image quality across all imaging modalities by modelling the ‘universal phantom’: breaking any phantom down into its constituent fundamental test objects and applying appropriate analysis techniques to these through the construction of an automated analysis tree. This is implemented practically through the new software package ‘IQWorks’ and is applicabl...

  19. Hemodynamic measurement using four-dimensional phase-contrast MRI: Quantification of hemodynamic parameters and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Ho Jin; Lee, Sang Joon [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang (Korea, Republic of); Kim, Guk Bae; Kweon, Ji Hoon; Kim, Young Hak; Lee, Deok Hee; Yang, Dong Hyun; KIm, Nam Kug [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI, in the investigation of spatial and temporal variations in hemodynamic features in cardiovascular blood flow. The present article reviews the principle and analytical procedures of 4D PC-MRI. Various fluid dynamic biomarkers for possible clinical usage are also described, including wall shear stress, turbulent kinetic energy, and relative pressure. Lastly, this article provides an overview of the clinical applications of 4D PC-MRI in various cardiovascular regions.

  20. The Partition Function in the Four-Dimensional Schwarz-Type Topological Half-Flat Two-Form Gravity

    Science.gov (United States)

    Abe, Mitsuko

    We derive the partition functions of the Schwarz-type four-dimensional topological half-flat two-form gravity model on K3-surface or T4 up to on-shell one-loop corrections. In this model the bosonic moduli spaces describe an equivalent class of a trio of the Einstein-Kähler forms (the hyper-Kähler forms). The integrand of the partition function is represented by the product of some bar ∂ -torsions. bar ∂ -torsion is the extension of R-torsion for the de Rham complex to that for the bar ∂ -complex of a complex analytic manifold.

  1. Hemodynamic Measurement Using Four-Dimensional Phase-Contrast MRI: Quantification of Hemodynamic Parameters and Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Hojin [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Kim, Guk Bae [Asan Institute of Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Kweon, Jihoon [Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Lee, Sang Joon [POSTECH Biotech Center, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang 37673 (Korea, Republic of); Kim, Young-Hak [Department of Cardiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Lee, Deok Hee; Yang, Dong Hyun [Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Kim, Namkug [Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of); Department of Convergence Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505 (Korea, Republic of)

    2016-11-01

    Recent improvements have been made to the use of time-resolved, three-dimensional phase-contrast (PC) magnetic resonance imaging (MRI), which is also named four-dimensional (4D) PC-MRI or 4D flow MRI, in the investigation of spatial and temporal variations in hemodynamic features in cardiovascular blood flow. The present article reviews the principle and analytical procedures of 4D PC-MRI. Various fluid dynamic biomarkers for possible clinical usage are also described, including wall shear stress, turbulent kinetic energy, and relative pressure. Lastly, this article provides an overview of the clinical applications of 4D PC-MRI in various cardiovascular regions.

  2. Assessment of Correlation between Chromosomal Radiosensitivity of Peripheral Blood Lymphocytes after In vitro Irradiation and Normal Tissue Side Effects for Cancer Patients Undergoing Radiotherapy.

    Science.gov (United States)

    Guogytė, Kamilė; Plieskienė, Aista; Ladygienė, Rima; Vaisiūnas, Žygimantas; Sevriukova, Olga; Janušonis, Vinsas; Žiliukas, Julius

    2017-01-01

    Patients receiving identical radiation treatments experience different effects, from undetectable to severe, on normal tissues. A crucial factor of radiotherapy related side effects is individual radiosensitivity. It is difficult to spare surrounding normal tissues delivering radiation to cancer cells during radiotherapy. Therefore, it may be useful to develop a simple routine cytogenetic assay which would allow the screening of a large number of individuals for radiosensitivity optimizing tumor control rates and minimizing severe radiotherapy effects with possibility to predict risk level for developing more severe early normal tissue adverse events after irradiation. This study was conducted to assess the correlation between in vitro radiosensitivity of peripheral blood lymphocytes from cancer patients who are undergoing radiotherapy using the cytokinesis-block micronucleus (CBMN), G2 chromosomal radiosensitivity assays, and normal tissue acute side effects. The CBMN and G2 chromosomal radiosensitivity assays were performed on blood samples taken from cancer patients before radiotherapy, after first fractionation, and after radiotherapy. Acute normal tissue reactions were graded according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer. This study suggests that there is a correlation between higher frequency of micronuclei after in vitro irradiation of blood samples and higher degree of normal tissue reactions. In addition, higher number of chromatid breaks was observed in patients with more severe normal tissue reactions. This pilot study included only 5 cancer patients, and therefore, further studies with a bigger cohort are required to identify radiosensitive patients.

  3. Quality of life in patients with oropharynx carcinomas: assessment after accelerated radiotherapy with or without chemotherapy versus radical surgery and postoperative radiotherapy.

    Science.gov (United States)

    Allal, Abdelkarim S; Nicoucar, Kevin; Mach, Nicolas; Dulguerov, Pavel

    2003-10-01

    In oropharyngeal carcinomas, it is assumed that the effectiveness of the different treatment approaches is roughly equivalent, whereas the functional outcome after radical radiotherapy (RT) is superior to that associated with primary surgery. The aim of this study is to assess quality of life (QoL) outcomes of patients after two treatment strategies: radical surgery with postoperative RT and accelerated concomitant boost RT with or without chemotherapy. Sixty patients who were disease free at least 1 year after treatment of oropharynx carcinoma were studied. Forty had been treated with radical RT (median tumor dose, 69.9 Gy in 5.5 weeks), and 20 had been treated with primary surgery and postoperative monofractionated RT (median dose, 60.2 Gy). Seven of the former patients received chemotherapy concomitantly with, and one before, RT. Functional outcome was assessed by the subjective Performance Status Scale for Head and Neck cancer (PSSHN) and the general QoL by the European Organization for Research and Treatment of Cancer Core QoL questionnaire (EORTC QLQ-C30). The unpaired t test was used to assess for significant differences between means. By use of the PSSHN module, scores were generally higher in the RT group, with a significant difference in the speech subscale (p =.005), a trend for a significant difference for the eating in public subscale (p =.08), and an insignificant difference for the normalcy of diet subscale (p =.25). When analyzed by tumor stage, no significant differences were observed for T1-2 tumors, whereas for patients with T3-4 tumors highly significant differences favoring the RT group became evident for all three subscales. Although no significant differences were observed using the EORTC QLQ C-30 functional scales, patients treated with primary surgery reported significantly more dyspnea (28 vs 12, p =.04) and appetite loss (30 vs 13, p =.05). In patients with T3-4 tumors, trends toward better scores favoring the RT group were observed for

  4. Motion of particles on a Four-Dimensional Asymptotically AdS Black Hole with Scalar Hair

    CERN Document Server

    Gonzalez, P A; Vasquez, Yerko

    2015-01-01

    Motivated by black hole solutions with matter fields outside their horizon, we study the effect of these matter fields in the motion of massless and massive particles. We consider as background a four-dimensional asymptotically AdS black hole with scalar hair. The geodesics are studied numerically and we discuss about the differences in the motion of particles between the four-dimensional asymptotically AdS black holes with scalar hair and their no-hair limit, that is, Schwarzschild AdS black holes. Mainly, we found that there are bounded orbits like planetary orbits in this background. However, the periods associated to circular orbits are modified by the presence of the scalar hair. Besides, we found that some classical tests such as perihelion precession, deflection of light and gravitational time delay have the standard value of general relativity plus a correction term coming from the cosmological constant and the scalar hair. Finally, we found a specific value of the parameter associated to the scalar h...

  5. Motion of particles on a four-dimensional asymptotically AdS black hole with scalar hair

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, P.A.; Olivares, Marco [Universidad Diego Portales, Facultad de Ingenieria, Santiago (Chile); Vasquez, Yerko [Universidad de La Serena, Departamento de Fisica, Facultad de Ciencias, La Serena (Chile)

    2015-10-15

    Motivated by black hole solutions with matter fields outside their horizon, we study the effect of these matter fields on the motion of massless and massive particles. We consider as background a four-dimensional asymptotically AdS black hole with scalar hair. The geodesics are studied numerically and we discuss the differences in the motion of particles between the four-dimensional asymptotically AdS black holes with scalar hair and their no-hair limit, that is, Schwarzschild AdS black holes. Mainly, we found that there are bounded orbits like planetary orbits in this background. However, the periods associated to circular orbits are modified by the presence of the scalar hair. Besides, we found that some classical tests such as perihelion precession, deflection of light, and gravitational time delay have the standard value of general relativity plus a correction term coming from the cosmological constant and the scalar hair. Finally, we found a specific value of the parameter associated to the scalar hair, in order to explain the discrepancy between the theory and the observations, for the perihelion precession of Mercury and light deflection. (orig.)

  6. Lessons from expert assessments of radiotherapy and interventional radiology accidents;Les enseignements des expertises des accidents de radiotherapie et de radiologie interventionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Repussard, J.; Gourmelon, P. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Fontenay-aux-Roses (France)

    2009-12-15

    Since 2005, around twenty radiotherapy or interventional radiology accidents, involving close to 600 patients, have occurred in France. IRSN made a detailed analysis of nine of them, at the request of the minister for public health, or of the nuclear safety authority. IRSN reports on these evaluations are publicly available on its web site www.irsn.fr. For the Epinal accident, the most serious of all, the minister also requested that IRSN deploy its operational knowledge in radio-pathology in order to help the patients suffering from the worst clinical damage from the overdose they had received. IRSN drew a number of recommendations from its analyses, both for the improvement of current professional practice or techniques, and for the priorities for new research aimed at better understanding of risks associated to modern radiotherapy techniques, and at the reduction of secondary effects of radiotherapy. IRSN key recommendations have since then been taken on board in the government guidelines to improve safety in radiotherapy. (authors)

  7. Validation of four-dimensional ultrasound for targeting in minimally-invasive beating-heart surgery

    Science.gov (United States)

    Pace, Danielle F.; Wiles, Andrew D.; Moore, John; Wedlake, Chris; Gobbi, David G.; Peters, Terry M.

    2009-02-01

    Ultrasound is garnering significant interest as an imaging modality for surgical guidance, due to its affordability, real-time temporal resolution and ease of integration into the operating room. Minimally-invasive intracardiac surgery performed on the beating-heart prevents direct vision of the surgical target, and procedures such as mitral valve replacement and atrial septal defect closure would benefit from intraoperative ultrasound imaging. We propose that placing 4D ultrasound within an augmented reality environment, along with a patient-specific cardiac model and virtual representations of tracked surgical tools, will create a visually intuitive platform with sufficient image information to safely and accurately repair tissue within the beating heart. However, the quality of the imaging parameters, spatial calibration, temporal calibration and ECG-gating must be well characterized before any 4D ultrasound system can be used clinically to guide the treatment of moving structures. In this paper, we describe a comprehensive accuracy assessment framework that can be used to evaluate the performance of 4D ultrasound systems while imaging moving targets. We image a dynamic phantom that is comprised of a simple robot and a tracked phantom to which point-source, distance and spherical objects of known construction can be attached. We also follow our protocol to evaluate 4D ultrasound images generated in real-time by reconstructing ECG-gated 2D ultrasound images acquired from a tracked multiplanar transesophageal probe. Likewise, our evaluation framework allows any type of 4D ultrasound to be quantitatively assessed.

  8. Response assessment after stereotactic body radiotherapy for spinal metastasis: a report from the SPIne response assessment in Neuro-Oncology (SPINO) group.

    Science.gov (United States)

    Thibault, Isabelle; Chang, Eric L; Sheehan, Jason; Ahluwalia, Manmeet S; Guckenberger, Matthias; Sohn, Moon-Jun; Ryu, Samuel; Foote, Matthew; Lo, Simon S; Muacevic, Alexander; Soltys, Scott G; Chao, Samuel; Gerszten, Peter; Lis, Eric; Yu, Eugene; Bilsky, Mark; Fisher, Charles; Schiff, David; Fehlings, Michael G; Ma, Lijun; Chang, Susan; Chow, Edward; Parelukar, Wendy R; Vogelbaum, Michael A; Sahgal, Arjun

    2015-12-01

    The SPine response assessment In Neuro-Oncology (SPINO) group is a committee of the Response Assessment in Neuro-Oncology working group and comprises a panel of international experts in spine stereotactic body radiotherapy (SBRT). Here, we present the group's first report on the challenges in standardising imaging-based assessment of local control and pain for spinal metastases. We review current imaging modalities used in SBRT treatment planning and tumour assessment and review the criteria for pain and local control in registered clinical trials specific to spine SBRT. We summarise the results of an international survey of the panel to establish the range of current practices in assessing tumour response to spine SBRT. The ultimate goal of the SPINO group is to report consensus criteria for tumour imaging, clinical assessment, and symptom-based response criteria to help standardise future clinical trials. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Application of four dimensional matrix for thermal analysis of Slovak transit gas pipeline by program FENIX

    Science.gov (United States)

    Széplaky, Dávid; Varga, Augustín

    2016-06-01

    The contribution describes the principle of the FENIX program operation, which was designed to determine the temperature field of the transit pipeline for the transportation of natural gas. The program itself consists of several modules which are reciprocally linked. The basis of the program is the elementary balance method by means of which the unsteady heat transfer is assigned in several layers in different directions. The first step was to assess both the pressure and temperature of the natural gas mode, the second step is to determine the heat transfer through the walls of the pipes, and the last one is to determine the distribution of the temperature field in the surroundings of the pipeline.

  10. Four-Dimensional Patient Dose Reconstruction for Scanned Ion Beam Therapy of Moving Liver Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Daniel [GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt (Germany); TU Darmstadt, Darmstadt (Germany); Saito, Nami [GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt (Germany); Chaudhri, Naved [Heidelberg Ion-Beam Therapy Center, Department of Medical Physics, Heidelberg (Germany); Härtig, Martin [University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Ellerbrock, Malte [Heidelberg Ion-Beam Therapy Center, Department of Medical Physics, Heidelberg (Germany); Jäkel, Oliver [Heidelberg Ion-Beam Therapy Center, Department of Medical Physics, Heidelberg (Germany); University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Combs, Stephanie E.; Habermehl, Daniel; Herfarth, Klaus [University Hospital of Heidelberg, Department of Radiation Oncology, Heidelberg (Germany); Durante, Marco [GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt (Germany); TU Darmstadt, Darmstadt (Germany); Bert, Christoph, E-mail: christoph.bert@uk-erlangen.de [GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt (Germany); University Clinic Erlangen and Friedrich-Alexander University Erlangen-Nürnberg, Department of Radiation Oncology, Erlangen (Germany)

    2014-05-01

    Purpose: Estimation of the actual delivered 4-dimensional (4D) dose in treatments of patients with mobile hepatocellular cancer with scanned carbon ion beam therapy. Methods and Materials: Six patients were treated with 4 fractions to a total relative biological effectiveness (RBE)–weighted dose of 40 Gy (RBE) using a single field. Respiratory motion was addressed by dedicated margins and abdominal compression (5 patients) or gating (1 patient). 4D treatment dose reconstructions based on the treatment records and the measured motion monitoring data were performed for the single-fraction dose and a total of 17 fractions. To assess the impact of uncertainties in the temporal correlation between motion trajectory and beam delivery sequence, 3 dose distributions for varying temporal correlation were calculated per fraction. For 3 patients, the total treatment dose was formed from the fractional distributions using all possible combinations. Clinical target volume (CTV) coverage was analyzed using the volumes receiving at least 95% (V{sub 95}) and 107% (V{sub 107}) of the planned doses. Results: 4D dose reconstruction based on daily measured data is possible in a clinical setting. V{sub 95} and V{sub 107} values for the single fractions ranged between 72% and 100%, and 0% and 32%, respectively. The estimated total treatment dose to the CTV exhibited improved and more robust dose coverage (mean V{sub 95} > 87%, SD < 3%) and overdose (mean V{sub 107} < 4%, SD < 3%) with respect to the single-fraction dose for all analyzed patients. Conclusions: A considerable impact of interplay effects on the single-fraction CTV dose was found for most of the analyzed patients. However, due to the fractionated treatment, dose heterogeneities were substantially reduced for the total treatment dose. 4D treatment dose reconstruction for scanned ion beam therapy is technically feasible and may evolve into a valuable tool for dose assessment.

  11. Assessing cancer patients' quality of life and coping mechanisms in Radiotherapy Department of the University College Hospital, Ibadan.

    Science.gov (United States)

    Asuzu, Chioma Christie; Elumelu, Theresa Nchekube

    2013-10-01

    Cancer is often associated with a lot of pain and suffering. These suggest that coping with the symptoms, diagnosis and treatment of cancer is a major life stressor that is capable of influencing patients' quality of life (QoL). The purpose of the study is to assess the relationship between cancer patients' QoL dimensions and coping strategies in the Radiotherapy Department of the University College Hospital Ibadan, Nigeria. Data were collected on clinic days from all available and consenting cancer patients who were receiving treatment at the radiotherapy department. Participants were informed of their right to decline to fill the questionnaires. In this study, 237 cancer patients participated. They had an age range of 15 to 95 years with a mean age of 49.91 years. There was significant inverse relationship between physical well-being with behavioural disengagement, venting, planning and self-blame (p coping, emotional support, positive reframing, instrumental support, acceptance and religion (p coping, instrumental support and acceptance (p coping strategies they are adopting to use in coping with their cancer burden, thereby guiding against lower QoL due to negative coping strategies. Intervention programmes could be developed to help cancer patients adopt more positive and effective coping strategies to improve patients' QoL. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Investigating the Impact on Modeled Ozone Concentrations Using Meteorological Fields From WRF With and Updated Four-Dimensional Data Assimilation Approach”

    Science.gov (United States)

    The four-dimensional data assimilation (FDDA) technique in the Weather Research and Forecasting (WRF) meteorological model has recently undergone an important update from the original version. Previous evaluation results have demonstrated that the updated FDDA approach in WRF pr...

  13. Dosimetric properties of MAGIC-f polymer gel assessed to Radiotherapy clinical beams

    Science.gov (United States)

    Marques, T.; Schwarcke, M.; Garrido C., E.; Baffa, O.; Nicolucci, P.

    2010-11-01

    Dosimetric properties of MAGIC-f gel were studied for a wide range of beams used in Radiotherapy. The MAGIC-f tissue-equivalence was theoretically verified using PENELOPE Monte Carlo code and experimentally by percentage depth dose curves for water and gel (maximum differences of 2.0% and 0.5% for 6MV and 10MV, respectively). Energy and dose-rate dependency were evaluated in a range from 60 kV to 10 MV and 0.44 Gy/min to 10 Gy/min respectively. MAGIC-f presents linearity to all energies studied and its sensitivity presents maximum and average variation of 8.6% and 7.7% respectively in the range of energy considered. The study of dose rate dependency evidence that MAGIC-f presents no significant variation of response in clinical intervals of dose rate: lower than 0.7% when x-ray are considered and lower than 1.9% when all beams are considered. Its dosimetric characteristics indicate that MAGIC-f is a very suitable dosimeter for Radiotherapy.

  14. Four-dimensional CT angiography (4D-CTA) in the evaluation of juvenile nasopharyngeal angiofibromas: comparison with digital subtraction angiography (DSA) and surgical findings.

    Science.gov (United States)

    Xiao, Zebin; Zheng, Yingyan; Li, Jian; Chen, Dehua; Liu, Fang; Cao, Dairong

    2017-10-10

    To explore the value of four-dimensional CT angiography (4D-CTA) in the preoperative evaluation of juvenile nasopharyngeal angiofibromas (JNAs) using 320-row volume CT. 4D-CTA and DSA data of 18 patients with histopathologically proven JNAs were retrospectively reviewed. The location, extent, feeding vessels and stage of JNAs were assessed by two radiologists independently and blindly. The agreements between both reviewers and between 4D-CTA and surgical findings for assessing the above indicators were analysed, respectively. The radiation dose and the number of feeding arteries between 4D-CTA and digital subtraction angiography (DSA) were also compared. 4D-CTA showed high diagnostic consistency with surgical pathology for JNAs with consistent rates of 96.2 and 100% in both reviewers, respectively. The effective dose of 4D-CTA was significantly less than that of DSA (p 0.05). 4D-CTA can provide a reliable preoperative diagnosis and assessment of JNAs, which is useful for determining the surgical strategy and management of this condition.

  15. Sensitivity of the model error parameter specification in weak-constraint four-dimensional variational data assimilation

    Science.gov (United States)

    Shaw, Jeremy A.; Daescu, Dacian N.

    2017-08-01

    This article presents the mathematical framework to evaluate the sensitivity of a forecast error aspect to the input parameters of a weak-constraint four-dimensional variational data assimilation system (w4D-Var DAS), extending the established theory from strong-constraint 4D-Var. Emphasis is placed on the derivation of the equations for evaluating the forecast sensitivity to parameters in the DAS representation of the model error statistics, including bias, standard deviation, and correlation structure. A novel adjoint-based procedure for adaptive tuning of the specified model error covariance matrix is introduced. Results from numerical convergence tests establish the validity of the model error sensitivity equations. Preliminary experiments providing a proof-of-concept are performed using the Lorenz multi-scale model to illustrate the theoretical concepts and potential benefits for practical applications.

  16. Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination

    DEFF Research Database (Denmark)

    Persson, Gitte Fredberg; Nygaard, Ditte Eklund; Af Rosenschöld, Per Munck

    2011-01-01

    PURPOSE: Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to com...

  17. Psychophysiological assessment of sexual function in women after radiotherapy and total mesorectal excision for rectal cancer : a pilot study on four patients

    NARCIS (Netherlands)

    Breukink, S.O.; Wouda, J.C.; van der Werf-Eldering, M.J.; van de Wiel, H.B.; Bouma, E.M.; Pierie, J.P.; Wiggers, T.; Meijerink, J.W.; Weijmar Schultz, W.C.

    INTRODUCTION: The potential contribution of psychological and anatomical changes to sexual dysfunction in female patients following short-term preoperative radiotherapy (5 x 5 Gy) and total mesorectal excision (TME) is not clear. Aim. In this study we assessed female sexual dysfunction in patients

  18. Longitudinal assessment of nutritional risk in patients under chemo or radiotherapy.

    Science.gov (United States)

    Mastelaro, Isabelle; Pupin, Mariana Pietrobom; Ribeiro, Sofia Miranda de Figueiredo; Oliveira, Harley Francisco de; Peria, Fernanda Maris; Cunha, Selma Freire de Carvalho da

    2016-10-01

    To compare nutritional risk in adult patients undergoing chemotherapy and radiotherapy in the beginning, middle, and end of oncologic treatment. This prospective, comparative study included 83 adult patients, 44 undergoing chemotherapy (CT group) and 39 undergoing radiotherapy (RT group) at an oncology treatment center. Nutritional risk was determined by NRS-2002 in the beginning, middle, and end of therapy. Statistical analysis was performed using Statistica 8.0 software. No differences in food intake or body mass index were observed between the CT (24.6±4.8 kg/m²) and RT groups (25.0±5.9 kg/m², p=0.75). Weight loss in the preceding 3 months was detected in 56.8% of CT group and 38.5% of RT group (p=0.09). The weight loss percentage compared with the usual weight within 3 months was greater (pnutritional risk (61.4 vs. 48.7%, p=0.25), with no statistical difference between the CT and RT groups, respectively. During therapy, the nutritional risk remained unaltered in both groups. In the end of therapy, the majority of patients were at moderate (18.2 vs. 12.8%, p=0.50) or severe nutritional risk (50.0 vs. 51.3%, p=0.91), in the CT and RT groups, respectively, regardless of the type of oncologic treatment. The high prevalence of patients at moderate or high nutritional risk in the beginning of treatment indicates the need for an early and continuous follow-up of the nutritional status of patients undergoing oncologic treatment.

  19. Longitudinal assessment of nutritional risk in patients under chemo or radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mastelaro, Isabelle; Pupin, Mariana Pietrobom; Ribeiro, Sofia Miranda de Figueiredo [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil); Oliveira, Harley Francisco de; Peria, Fernanda Maris; Cunha, Selma Freire de Carvalho da, E-mail: sfreire@fmrp.usp.br [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina

    2016-10-15

    Objective: To compare nutritional risk in adult patients undergoing chemotherapy and radiotherapy in the beginning, middle, and end of oncologic treatment. Method: This prospective, comparative study included 83 adult patients, 44 undergoing chemotherapy (CT group) and 39 undergoing radiotherapy (RT group) at an oncology treatment center. Nutritional risk was determined by NRS-2002 in the beginning, middle, and end of therapy. Statistical analysis was performed using Statistica 8.0 software. Results: No differences in food intake or body mass index were observed between the CT (24.6±4.8 kg/m²) and RT groups (25.0±5.9 kg/m², p=0.75). Weight loss in the preceding 3 months was detected in 56.8% of CT group and 38.5% of RT group (p=0.09). The weight loss percentage compared with the usual weight within 3 months was greater (p<0.001) in the CT (11.4±6.5%) than in the RT group (3.9±6.8%). In the beginning of treatment, we observed high percentages of patients at moderate (18.2 vs. 15.4%, p=0.73) and high nutritional risk (61.4 vs. 48.7%, p=0.25), with no statistical difference between the CT and RT groups, respectively. During therapy, the nutritional risk remained unaltered in both groups. In the end of therapy, the majority of patients were at moderate (18.2 vs. 12.8%, p=0.50) or severe nutritional risk (50.0 vs. 51.3%, p=0.91), in the CT and RT groups, respectively, regardless of the type of oncologic treatment. Conclusion: The high prevalence of patients at moderate or high nutritional risk in the beginning of treatment indicates the need for an early and continuous follow-up of the nutritional status of patients undergoing oncologic treatment. (author)

  20. Impaired DNA repair as assessed by the ``comet`` assay in patients developing thyroid carcinoma after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Leprat, F.; Sarasin, A.; Suarez, H.G. [Institut de Recherches sur le Cancer, 94 - Villesuif (France); Leprat, F.; Alapetite, C.; Rosselli, F.; Ridet, A.; Moustacch, E.; Alapetite, C. [Institut Curie, 75 - Paris (France); Schlumberger, M. [Institut Gustave Roussy, 94 - Villejuif (France)

    1997-03-01

    A defective cellular response to DNA lesions induced be genotoxic agents may be associated to an increased cancer proneness. This has been clearly identified in some rare but extensively studied genetic diseases such as xeroderma pigmentosum (XP), ataxia telangiectasia (AT) and Fanconi anemia (FA). In practical oncology, most patients receive genotoxic therapeutic agents and the presence of so far unidentified sensitive genotypes could account for an increased susceptibility to cancer in a subgroup of exposed patients. The thyroid gland of children is especially sensitive to the carcinogenic effect of ionizing radiation. Evidence for risk is reported even at doses as low as 0.1 Gy, and the excess relative risk to develop a thyroid tumor following a radiation dose of 1 Gy in childhood is of 7.7 [l]. In order to determine if a defect in repair of DNA strand breaks could be involved, as an early step, in the development of secondary thyroid tumors after radiotherapy, we examined, using the alkaline single cell gel electrophoresis assay (SCGE or `comet`), the response to in vitro {gamma}-rays exposure of lymphocytes of a small group of patients who developed thyroid carcinoma after radiotherapy for a primary tumor. Because of its practical advantages, the alkaline comet assay offers the opportunity to question the role of DNA strand beaks rejoining capacity of the individual in the radiation induced carcinogenesis of thyroid tumors. This preliminary study of a small group of patients with therapeutic irradiation at childhood for a primary tumor indicates that, at the time of blood sampling, lymphocytes of some of these patients demonstrated reduced rejoining capacity. These results suggest that the comet assay might help to distinguish a subgroup of individuals at risk for radiation induced genomic instability and encourage further investigation. (authors)

  1. Assessment of pulmonary toxicities in breast cancer patients undergoing treatment with anthracycline and taxane based chemotherapy and radiotherapy- a prospective study

    Directory of Open Access Journals (Sweden)

    Aramita Saha

    2013-12-01

    Full Text Available Background: Anthracycline based regiments and/or taxanes and adjuvant radiotherapy; the main modalities of treatment for breast cancers are associated with deterioration of pulmonary functions and progressive pulmonary toxicities. Aim: Assessment of pulmonary toxicities and impact on pulmonary functions mainly in terms of decline of forced vital capacity (FVC and the ratio of forced expiratory volume (FEV in 1 Second and FEV1/FVC ratio with different treatment times and follow ups in carcinoma breast patients receiving anthracycline and/or taxane based chemotherapy and radiotherapy. Materials and methods: A prospective single institutional cohort study was performed with 58 breast cancer patients between January 2011 to July 2012 who received either anthracycline based (37 patients received 6 cycles FAC= 5 FU, Adriamycin, Cyclophosphamide regime and radiotherapy or anthracycline and taxane based chemotherapy (21 patients received 4cycles AC= Adriamycin, Cyclophosphamide; followed by 4 cycles of T=Taxane and radiotherapy. Assessment of pulmonary symptoms and signs, chest x-ray and pulmonary function tests were performed at baseline, midcycle, at end of chemotherapy, at end radiotherapy, at 1 and 6 months follow ups and compared. By means of a two-way analysis of variance (ANOVA model, the course of lung parameters across the time points was compared. Results and Conclusion: Analysis of mean forced vital capacities at different points of study times showed definitive declining pattern, which is at statistically significant level at the end of 6th month of follow up (p=0.032 .The FEV1/FVC ratio (in percentage also revealed a definite decreasing pattern over different treatment times and at statistically significant level at 6th month follow up with p value 0.003. Separate analysis of mean FEV1/FVC ratios over time in anthracycline based chemotherapy and radiotherapy group as well as anthracycline and taxane based chemotherapy and radiotherapy group

  2. A novel four-dimensional angiographic approach to assess dynamic superficial wall stress of coronary arteries in vivo

    DEFF Research Database (Denmark)

    Wu, Xinlei; von Birgelen, Clemens; Muramatsu, Takashi

    2017-01-01

    it for the first time in two clinical cases to investigate the potential relationship between dynamic stress concentration at baseline and plaque rupture during acute coronary syndrome (ACS) several months later. METHODS AND RESULTS: Three-dimensional angiographic reconstructions of the interrogated arteries were...... performed at several phases of the cardiac cycle, followed by finite element analysis to obtain the dynamic SWS data. The peak stress at baseline was found at the distal and proximal lesion longitudinal shoulders, being 121.8kPa and 98.0kPa, respectively. Intriguingly, in both cases, the sites...

  3. A novel application of four-dimensional magnetic resonance angiography using an arterial spin labeling technique for noninvasive diagnosis of Moyamoya disease.

    Science.gov (United States)

    Uchino, Haruto; Ito, Masaki; Fujima, Noriyuki; Kazumata, Ken; Yamazaki, Kazuyoshi; Nakayama, Naoki; Kuroda, Satoshi; Houkin, Kiyohiro

    2015-10-01

    Noncontrast-enhanced time-resolved four-dimensional magnetic resonance angiography using an arterial spin labeling technique (ASL-4D MRA) is emerging as a next generation angiography for the management of neurovascular diseases. This study evaluated the feasibility of ASL-4D MRA for the diagnosis of Moyamoya disease (MMD) and MMD staging by using digital subtraction angiography (DSA) and time-of-flight MRA (TOF MRA) as current standards. Eleven consecutive non-operated patients who underwent DSA for the diagnosis of MMD were recruited. Two independent observers evaluated the three tests. The data were analyzed for inter-observer and inter-modality agreements on MMD stage. Nine of 22 hemispheres underwent surgical revascularization and ASL-4D MRA was repeated postoperatively. Time-resolved inflow of blood through the cerebral vessels, including moyamoya vessels, was visualized in all the 22 non-operated hemispheres. MMD stages assessed by DSA and ASL-4D MRA were completely matched in 18 hemispheres, with a significant positive correlation between these modalities (r=0.93, Pangiography may be useful for monitoring disease evolution and treatment response in cerebral arteries after revascularization surgery in MMD. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Quality of life of women with breast cancer undergoing radiotherapy using the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire.

    Science.gov (United States)

    Muszalik, Marta; Kołucka-Pluta, Małgorzata; Kędziora-Kornatowska, Kornelia; Robaczewska, Joanna

    2016-01-01

    Breast cancer is one of the most common cancers in women, particularly among older women. This illness along with its treatment has a great impact on a woman's subjective opinion of her quality of life and functioning in everyday life. The aim of this research was to assess the quality of life in women undergoing radiotherapy for the treatment of breast cancer. The research was carried out in 120 patients with breast cancer undergoing radiotherapy in the Oncological Center in Bydgoszcz, Poland. Among the 120 examined patients, there were 30 women aged between 20-50 years and the remaining were over 50 years of age, including 42 women over the age of 60. Demographic and clinical data were collected and the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire (version 4) was used to assess health-related quality of life (HRQOL) of the patients. Statistical analyses were conducted using Statistica, version 10.0. Patients with breast cancer undergoing radiotherapy rated their quality of life with an average of 113.83 points. Older patients above 71 years of age also displayed significantly higher HRQOL (122.70 points). A lower level of fatigue was noticed among patients ≤50 years and ≥71 years of age. Education and marital status also had an important impact on HRQOL. Educated women with a good financial situation had a significantly higher HRQOL, compared to those with a lower education and in poor living conditions. HRQOL and state of fatigue in breast cancer patients treated with radiotherapy depended upon their age. Both were high among women aged 71 years and above, while younger patients (51-70 years of age) had slightly lower values. Results suggest that sociodemographic factors influence the conditions of life of women treated with radiotherapy for breast cancer in a significant way. Overall, patients tolerated this type of treatment well.

  5. Four-dimensional Cone Beam CT Reconstruction and Enhancement using a Temporal Non-Local Means Method

    CERN Document Server

    Jia, Xun; Lou, Yifei; Sonke, Jan-Jakob; Jiang, Steve B

    2012-01-01

    Four-dimensional Cone Beam Computed Tomography (4D-CBCT) has been developed to provide respiratory phase resolved volumetric imaging in image guided radiation therapy (IGRT). Inadequate number of projections in each phase bin results in low quality 4D-CBCT images with obvious streaking artifacts. In this work, we propose two novel 4D-CBCT algorithms: an iterative reconstruction algorithm and an enhancement algorithm, utilizing a temporal nonlocal means (TNLM) method. We define a TNLM energy term for a given set of 4D-CBCT images. Minimization of this term favors those 4D-CBCT images such that any anatomical features at one spatial point at one phase can be found in a nearby spatial point at neighboring phases. 4D-CBCT reconstruction is achieved by minimizing a total energy containing a data fidelity term and the TNLM energy term. As for the image enhancement, 4D-CBCT images generated by the FDK algorithm are enhanced by minimizing the TNLM function while keeping the enhanced images close to the FDK results. A...

  6. Sin-quadratic model for chest tomosynthesis respiratory signal analysis and its application in four dimensional chest tomosynthesis reconstruction.

    Science.gov (United States)

    Tao, Xi; Zhang, Hua; Qin, Genggeng; Ma, Jianhua; Feng, Qianjin; Chen, Wufan

    2018-02-01

    Chest tomosynthesis (CTS) is a newly developed imaging technique which provides pseudo-3D volume anatomical information of thorax from limited-angle projections and contains much less of superimposed anatomy than the chest X-ray radiography. One of the relatively common problems in CTS is the patient respiratory motion during image acquisition, which negatively impacts the detectability. In this work, we propose a sin-quadratic model to analyze the respiratory motion during CTS scan, which is a real time method where the respiratory signal is generated by extracting the motion of diaphragm from projection radiographs. According to the estimated respiratory signal, the CTS projections were then amplitude-based sorted into four to eight phases, and an iterative reconstruction strategy with total variation regularization was adopted to reconstruct the CTS images at each phase. Simulated digital XCAT phantom data and three sets of patient data were adopted for the experiments to validate the performance of the sin-quadratic model and its application in four dimensional (4D) CTS reconstruction. Results of the XCAT phantom simulation study show that the correlation coefficient between the extracted respiratory signal and the originally designed respiratory signal is 0.9964, which suggests that the proposed model could exactly extract the respiratory signal from CTS projections. The 4D CTS reconstructions of both the phantom data and the patient data show clear reduction of motion-induced blur. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.

  7. A novel color image encryption algorithm based on genetic recombination and the four-dimensional memristive hyperchaotic system

    Science.gov (United States)

    Chai, Xiu-Li; Gan, Zhi-Hua; Lu, Yang; Zhang, Miao-Hui; Chen, Yi-Ran

    2016-10-01

    Recently, many image encryption algorithms based on chaos have been proposed. Most of the previous algorithms encrypt components R, G, and B of color images independently and neglect the high correlation between them. In the paper, a novel color image encryption algorithm is introduced. The 24 bit planes of components R, G, and B of the color plain image are obtained and recombined into 4 compound bit planes, and this can make the three components affect each other. A four-dimensional (4D) memristive hyperchaotic system generates the pseudorandom key streams and its initial values come from the SHA 256 hash value of the color plain image. The compound bit planes and key streams are confused according to the principles of genetic recombination, then confusion and diffusion as a union are applied to the bit planes, and the color cipher image is obtained. Experimental results and security analyses demonstrate that the proposed algorithm is secure and effective so that it may be adopted for secure communication. Project supported by the National Natural Science Foundation of China (Grant Nos. 61203094 and 61305042), the Natural Science Foundation of the United States (Grant Nos. CNS-1253424 and ECCS-1202225), the Science and Technology Foundation of Henan Province, China (Grant No. 152102210048), the Foundation and Frontier Project of Henan Province, China (Grant No. 162300410196), the Natural Science Foundation of Educational Committee of Henan Province, China (Grant No. 14A413015), and the Research Foundation of Henan University, China (Grant No. xxjc20140006).

  8. Evaluation of four-dimensional nonbinary LDPC-coded modulation for next-generation long-haul optical transport networks.

    Science.gov (United States)

    Zhang, Yequn; Arabaci, Murat; Djordjevic, Ivan B

    2012-04-09

    Leveraging the advanced coherent optical communication technologies, this paper explores the feasibility of using four-dimensional (4D) nonbinary LDPC-coded modulation (4D-NB-LDPC-CM) schemes for long-haul transmission in future optical transport networks. In contrast to our previous works on 4D-NB-LDPC-CM which considered amplified spontaneous emission (ASE) noise as the dominant impairment, this paper undertakes transmission in a more realistic optical fiber transmission environment, taking into account impairments due to dispersion effects, nonlinear phase noise, Kerr nonlinearities, and stimulated Raman scattering in addition to ASE noise. We first reveal the advantages of using 4D modulation formats in LDPC-coded modulation instead of conventional two-dimensional (2D) modulation formats used with polarization-division multiplexing (PDM). Then we demonstrate that 4D LDPC-coded modulation schemes with nonbinary LDPC component codes significantly outperform not only their conventional PDM-2D counterparts but also the corresponding 4D bit-interleaved LDPC-coded modulation (4D-BI-LDPC-CM) schemes, which employ binary LDPC codes as component codes. We also show that the transmission reach improvement offered by the 4D-NB-LDPC-CM over 4D-BI-LDPC-CM increases as the underlying constellation size and hence the spectral efficiency of transmission increases. Our results suggest that 4D-NB-LDPC-CM can be an excellent candidate for long-haul transmission in next-generation optical networks.

  9. Testing Four Dimensional Variational Data Assimilation Method Using an Improved Intermediate Coupled Model for ENSO Analysis and Prediction

    Science.gov (United States)

    Gao, C.; Zhang, R. H.

    2016-12-01

    A four dimensional variational (4D-Var) data assimilation method is implemented in an improved intermediate coupled model (ICM) of the tropical Pacific. The ICM has ten baroclinic modes in the vertical, with horizonatally varying stratification taken into account; two empirical submodels are constructed from historical data, one for the subsurface entrainment temperature in the surface mixed layer (Te) in terms of sea level (SL) anomalies and another for the wind stress (τ) in terms of sea surface temperature (SST) anomalies. A twin experiment is established to evaluate the impact of the 4D-Var data assimilation algorithm on the El Niño and Southern Oscillation (ENSO) analysis and prediction. The model error is assumed to arise only from the parameter uncertainty. The "observation" of sea surface temperature (SST) anomaly is sampled from the "truth" model that takes default parameter values and added by a Gaussian noise, is directly assimilated into the assimilation model with its parameters being set erroneously. Results show that the 4D-Var effectively reduces the error of ENSO analysis and therefore improves the prediction skill of ENSO events at 12-month lead time compared with the non-assimilation case. These provide a promising way for the ICM in its better real-time ENSO prediction.

  10. Four-Dimensional (4D) Printing: A New Evolution in Computed Tomography-Guided Stereolithographic Modeling. Principles and Application.

    Science.gov (United States)

    Chae, Michael P; Hunter-Smith, David J; De-Silva, Inoka; Tham, Stephen; Spychal, Robert T; Rozen, Warren Matthew

    2015-07-01

    Over the last decade, image-guided production of three-dimensional (3D) haptic biomodels, or rapid prototyping (RP), has transformed the way surgeons conduct preoperative planning. In contrast to earlier RP techniques such as stereolithography, 3D printing has introduced fast, affordable office-based manufacturing. We introduce the concept of 4D printing for the first time by introducing time as the fourth dimension to 3D printing. The bones of the thumb ray are 3D printed during various movements to demonstrate four-dimensional (4D) printing. Principles and validation studies are presented here. 4D computed tomography was performed using "single volume acquisition" technology to reduce the exposure to radiation. Three representative scans of each thumb movement (i.e., abduction, opposition, and key pinch) were selected and then models were fabricated using a 3D printer. For validation, the angle between the first and the second metacarpals from the 4D imaging data and the 4D-printed model was recorded and compared. We demonstrate how 4D printing accurately depicts the transition in the position of metacarpals during thumb movement. With a fourth dimension of time, 4D printing delivers complex spatiotemporal anatomical details effortlessly and may substantially improve preoperative planning. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. Measurement of micro-scale soil deformation around roots using four-dimensional synchrotron tomography and image correlation.

    Science.gov (United States)

    Keyes, S D; Cooper, L; Duncan, S; Koebernick, N; McKay Fletcher, D M; Scotson, C P; van Veelen, A; Sinclair, I; Roose, T

    2017-11-01

    This study applied time lapse (four-dimensional) synchrotron X-ray computed tomography to observe micro-scale interactions between plant roots and soil. Functionally contrasting maize root tips were repeatedly imaged during ingress into soil columns of varying water content and compaction. This yielded sequences of three-dimensional densiometric data, representing time-resolved geometric soil and root configurations at the micronmetre scale. These data were used as inputs for two full-field kinematic quantification methods, which enabled the analysis of three-dimensional soil deformation around elongating roots. Discrete object tracking was used to track rigid mineral grains, while continuum digital volume correlation was used to track grey-level patterns within local sub-volumes. These techniques both allowed full-field soil displacements to be quantified at an intra-rhizosphere spatial sampling scale of less than 300 µm. Significant differences in deformation mechanisms were identified around different phenotypes under different soil conditions. A uniquely strong contrast was observed between intact and de-capped roots grown in dry, compacted soil. This provides evidence that functional traits of the root cap significantly reduce the amount of soil disturbance per unit of root elongation, with this effect being particularly significant in drier soil. © 2017 The Author(s).

  12. Inflow hemodynamics evaluated by using four-dimensional flow magnetic resonance imaging and the size ratio of unruptured cerebral aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Futami, Kazuya [Matto-Ishikawa Central Hospital, Department of Neurosurgery, Hakusan, Ishikawa (Japan); Nambu, Iku; Kitabayashi, Tomohiro; Sano, Hiroki; Misaki, Kouichi; Uchiyama, Naoyuki; Nakada, Mitsutoshi [Kanazawa University School of Medicine, Department of Neurosurgery, Kanazawa, Ishikawa (Japan)

    2017-04-15

    Prediction of the rupture risk is critical for the identification of unruptured cerebral aneurysms (UCAs) eligible for invasive treatments. The size ratio (SR) is a strong morphological predictor for rupture. We investigated the relationship between the inflow hemodynamics evaluated on four-dimensional (4D) flow magnetic resonance (MR) imaging and the SR to identify specific characteristics related to UCA rupture. We evaluated the inflow jet patterns and inflow hemodynamic parameters of 70 UCAs on 4D flow MR imaging and compared them among 23 aneurysms with an SR ≥2.1 and 47 aneurysms with an SR ≤2.0. Based on the shape of inflow streamline bundles with a velocity ≥75% of the maximum flow velocity in the parent artery, the inflow jet patterns were classified as concentrated (C), diffuse (D), neck-limited (N), and unvisualized (U). The incidence of patterns C and N was significantly higher in aneurysms with an SR ≥2.1. The rate of pattern U was significantly higher in aneurysms with an SR ≤2.0. The maximum inflow rate and the inflow rate ratio were significantly higher in aneurysms with an SR ≥2.1. The SR affected the inflow jet pattern, the maximum inflow rate, and the inflow rate ratio of UCAs. In conjunction with the SR, inflow hemodynamic analysis using 4D flow MR imaging may contribute to the risk stratification for aneurysmal rupture. (orig.)

  13. Curvature invariant characterization of event horizons of four-dimensional black holes conformal to stationary black holes

    Science.gov (United States)

    McNutt, David D.

    2017-11-01

    We introduce three approaches to generate curvature invariants that transform covariantly under a conformal transformation of a four-dimensional spacetime. For any black hole conformally related to a stationary black hole, we show how a set of conformally covariant invariants can be combined to produce a conformally covariant invariant that detects the event horizon of the conformally related black hole. As an application we consider the rotating dynamical black holes conformally related to the Kerr-Newman-Unti-Tamburino-(anti)-de Sitter spacetimes and construct an invariant that detects the conformal Killing horizon along with a second invariant that detects the conformal stationary limit surface. In addition, we present necessary conditions for a dynamical black hole to be conformally related to a stationary black hole and apply these conditions to the ingoing Kerr-Vaidya and Vaidya black hole solutions to determine if they are conformally related to stationary black holes for particular choices of the mass function. While two of the three approaches cannot be generalized to higher dimensions, we discuss the existence of a conformally covariant invariant that will detect the event horizon for any higher dimensional black hole conformally related to a stationary black hole which admits at least two conformally covariant invariants, including all vacuum spacetimes.

  14. Unified registration framework for cumulative dose assessment in cervical cancer across external beam radiotherapy and brachytherapy

    Science.gov (United States)

    Roy, Sharmili; Totman, John J.; Choo, Bok A.

    2016-03-01

    Dose accumulation across External Beam Radiotherapy (EBRT) and Brachytherapy (BT) treatment fractions in cervical cancer is extremely challenging due to structural dissimilarities and large inter-fractional anatomic deformations between the EBRT and BT images. The brachytherapy applicator and the bladder balloon, present only in the BT images, introduce missing structural correspondences for the underlying registration problem. Complex anatomical deformations caused by the applicator and the balloon, different rectum and bladder filling and tumor shrinkage compound the registration difficulties. Conventional free-form registration methods struggle to handle such topological differences. In this paper, we propose a registration pipeline that first transforms the original images to their distance maps based on segmentations of critical organs and then performs non-linear registration of the distance maps. The resulting dense deformation field is then used to transform the original anatomical image. The registration accuracy is evaluated on 27 image pairs from stage 2B-4A cervical cancer patients. The algorithm reaches a Hausdorff distance of close to 0:5 mm for the uterus, 2:2 mm for the bladder and 1:7 mm for the rectum when applied to (EBRT,BT) pairs, taken at time points more than three months apart. This generalized model-free framework can be used to register any combination of EBRT and BT images as opposed to methods in the literature that are tuned for either only (BT,BT) pair, or only (EBRT,EBRT) pair or only (BT,EBRT) pair. A unified framework for 3D dose accumulation across multiple EBRT and BT fractions is proposed to facilitate adaptive personalized radiation therapy.

  15. Measurement of the transverse four-dimensional beam rms-emittance of an intense uranium beam at 11.4 MeV/u

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, C.; Groening, L.; Gerhard, P.; Maier, M.; Mickat, S.; Vormann, H.

    2016-06-01

    Knowledge of the transverse four-dimensional beam rms-parameters is essential for applications that involve lattice elements that couple the two transverse degrees of freedom (planes). Usually pepper-pots are used for measuring these beam parameters. However, for ions their application is limited to energies below 150 keV/u. This contribution is on measurements of the full transverse four-dimensional second-moments beam matrix of high intensity uranium ions at an energy of 11.4 MeV/u. The combination of skew quadrupoles with a slit/grid emittance measurement device has been successfully applied.

  16. Preclinical dynamic 18F-FDG PET - tumor characterization and radiotherapy response assessment by kinetic compartment analysis

    Energy Technology Data Exchange (ETDEWEB)

    Roee, Kathrine; Aleksandersen, Thomas B.; Nilsen, Line B.; Hong Qu; Ree, Anne H.; Malinen, Eirik (Univ. of Oslo, Oslo (Norway)), E-mail: Kathrine.Roe@rr-research.no; Kristian, Alexandr (Dept. of Tumor Biology, Inst. for Cancer Research, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)); Seierstad, Therese (Dept. of Radiation Biology, Inst. for Cancer Research, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)); Olsen, Dag R. (Univ. of Bergen, Bergen (Norway))

    2010-10-15

    Background. Non-invasive visualization of tumor biological and molecular processes of importance to diagnosis and treatment response is likely to be critical in individualized cancer therapy. Since conventional static 18F-FDG PET with calculation of the semi-quantitative parameter standardized uptake value (SUV) may be subject to many sources of variability, we here present an approach of quantifying the 18F-FDG uptake by analytic two-tissue compartment modeling, extracting kinetic tumor parameters from dynamic 18F-FDG PET. Further, we evaluate the potential of such parameters in radiotherapy response assessment. Material and methods. Male, athymic mice with prostate carcinoma xenografts were subjected to dynamic PET either untreated (n=8) or 24 h post-irradiation (7.5 Gy single dose, n=8). After 10 h of fasting, intravenous bolus injections of 10-15 MBq 18F-FDG were administered and a 1 h dynamic PET scan was performed. 4D emission data were reconstructed using OSEM-MAP, before remote post-processing. Individual arterial input functions were extracted from the image series. Subsequently, tumor 18F-FDG uptake was fitted voxel-by-voxel to a compartment model, producing kinetic parameter maps. Results. The kinetic model separated the 18F-FDG uptake into free and bound tracer and quantified three parameters; forward tracer diffusion (k1), backward tracer diffusion (k2), and rate of 18F-FDG phosphorylation, i.e. the glucose metabolism (k3). The fitted kinetic model gave a goodness of fit (r2) to the observed data ranging from 0.91 to 0.99, and produced parametrical images of all tumors included in the study. Untreated tumors showed homogeneous intra-group median values of all three parameters (k1, k2 and k3), whereas the parameters significantly increased in the tumors irradiated 24 h prior to 18F-FDG PET. Conclusions. This study demonstrates the feasibility of a two-tissue compartment kinetic analysis of dynamic 18F-FDG PET images. If validated, extracted parametrical

  17. An Assessment of Spinal Cord Dose Following Radiotherapy of Nasopharyngeal Cancer by TLD and Rando Phantom

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Bahreyni Toossi

    2009-12-01

    Full Text Available Introduction: Nasopharyngeal carcinoma is one of the most common malignancies in the head and neck region and radiotherapy is its treatment of choice. In spite of the fact that it is widely used, due to the presence of many sensitive organs or tissues in this region, patients may suffer from a wide range of side effects. One such sensitive tissue is the spinal cord. If the absorbed dose to spinal cord is greater than its tolerance dose, then myelopathy and Lhermitte’s sign are not avoidable. Material and Methods: Thehead and neck of a Rando phantom (reference man was employed as a hypothetical patient suffering from nasopharyngeal carcinoma. The full course of treatment consisted of three phases. At the beginning of every phase, an oncologist used a simulator to delineate the surface of the Rando Phantom for treatment. TLD chips (TLD-100 were employed for dose measurement. TLD chips were inserted in the previously made holes on the surface of selected slices adjacent to second cervical to fourth thoracic vertebra. Absorbed dose by TLDs were read by a Harshaw 3500 TLD reader. Results: Total measured dose (in Gy of various parts of spinal cord adjacent to second cervical to fourth thoracic vertebra varied widely and were as follows respectively: 15.24±1.31, 50.31±1.06, 49.15±2.77, 47.48±1.42, 54.56±2.6, 48.92±0.6, 45.1±0.45. In other words, the range of doses received by different segments of the spinal cord could be as wide as 15.24 to 54.56 Gy. Conclusion: Although the spinal cord was excluded at the end of the first phase, a significant change in the absorbed dose at the end of the first and second phases was not observed. In phase three, the anterior neck field was replaced by a lateral field and the spinal cord absorbed dose was reduced considerably. According to our results, absorbed doses of the spinal cord segments corresponding to the region confined between the third cervical to third thoracic vertebra were more than the 47 Gy

  18. Quantitative dosimetric assessment for effect of gold nanoparticles as contrast media on radiotherapy planning

    Science.gov (United States)

    Tu, Shu-Ju; Yang, Pei-Ying; Hong, Ji-Hong; Lo, Ching-Jung

    2013-07-01

    In CT planning for radiation therapy, patients may be asked to have a medical procedure of contrast agent (CA) administration as required by their physicians. CA media improve quality of CT images and assist radiation oncologists in delineation of the target or organs with accuracy. However, dosimetric discrepancy may occur between scenarios in which CA media are present in CT planning and absent in treatment delivery. In recent preclinical experiments of small animals, gold nanoparticles (AuNPs) have been identified as an excellent contrast material of x-ray imaging. In this work, we quantitatively evaluate the effect of AuNPs to be used as a potential material of contrast enhancement in radiotherapy planning with an analytical phantom and clinical case. Conray 60, an iodine-based product for contrast enhancement in clinical uses, is included as a comparison. Other additional variables such as different concentrations of CA media, radiation delivery techniques and dose calculation algorithms are included. We consider 1-field AP, 4-field box, 7-field intensity modulated radiation therapy (IMRT) and a recent technique of volumetric modulated arc therapy (VMAT). CA media of AuNPs (Conray 60) with concentrations of 10%, 20%, 30%, 40% and 50% containing 28.2, 56.4, 84.6, 112.8 and 141.0 mg of gold (iodine) per mL were prepared prior to CT scanning. A virtual phantom with a target where nanoparticle media are loaded and clinical case of gastric lymphoma in which the Conray 60 media were given to the patient prior to the CT planning are included for the study. Compared to Conray 60 media with concentration of 10%/50%, Hounsfield units for AuNP media of 10%/50% are 322/1608 higher due to the fact that atomic number of Au (Z=79) is larger than I (Z=53). In consequence, dosimetric discrepancy of AuNPs is magnified between presence and absence of contrast media. It was found in the phantom study that percent dose differences between presence and absence of CA media may be

  19. Dynamic measurement of the optical properties of bovine enamel demineralization models using four-dimensional optical coherence tomography

    Science.gov (United States)

    Aden, Abdirahman; Anthony, Arthi; Brigi, Carel; Merchant, Muhammad Sabih; Siraj, Huda; Tomlins, Peter H.

    2017-07-01

    Dental enamel mineral loss is multifactorial and is consequently explored using a variety of in vitro models. Important factors include the presence of acidic pH and its specific ionic composition, which can both influence lesion characteristics. Optical coherence tomography (OCT) has been demonstrated as a promising tool for studying dental enamel demineralization. However, OCT-based characterization and comparison of demineralization model dynamics are challenging without a consistent experimental environment. Therefore, an automated four-dimensional OCT system was integrated with a multispecimen flow cell to measure and compare the optical properties of subsurface enamel demineralization in different models. This configuration was entirely automated, thus mitigating any need to disturb the specimens and ensuring spatial registration of OCT image volumes at multiple time points. Twelve bovine enamel disks were divided equally among three model groups. The model demineralization solutions were citric acid (pH 3.8), acetic acid (pH 4.0), and acetic acid with added calcium and phosphate (pH 4.4). Bovine specimens were exposed to the solution continuously for 48 h. Three-dimensional OCT data were obtained automatically from each specimen at a minimum of 1-h intervals from the same location within each specimen. Lesion dynamics were measured in terms of the depth below the surface to which the lesion extended and the attenuation coefficient. The net loss of surface enamel was also measured for comparison. Similarities between the dynamics of each model were observed, although there were also distinct characteristic differences. Notably, the attenuation coefficients showed a systematic offset and temporal shift with respect to the different models. Furthermore, the lesion depth curves displayed a discontinuous increase several hours after the initial acid challenge. This work demonstrated the capability of OCT to distinguish between different enamel demineralization

  20. Near-infrared spectra and rovibrational dynamics on a four-dimensional ab initio potential energy surface of (HBr)2.

    Science.gov (United States)

    Castillo-Chará, J; McIntosh, A L; Wang, Z; Lucchese, R R; Bevan, J W

    2004-06-08

    Supersonic jet investigations of the (HBr)(2) dimer have been carried out using a tunable diode laser spectrometer to provide accurate data for comparison with results from a four-dimensional (4-D) ab initio potential energy surface (PES). The near-infrared nu(1) (+/-), nu(2) (+/-), and (nu(1)+nu(4))(-) bands of (H (79)Br)(2), (H (79)Br-H (81)Br), and (H (81)Br)(2) isotopomers have been recorded in the range 2500-2600 cm(-1) using a CW slit jet expansion with an upgraded near-infrared diode laser spectrometer. The 4-D PES has been calculated for (HBr)(2) using second-order Møller-Plesset perturbation theory with an augmented and polarized 6-311G basis set. The potential is characterized by a global minimum occurring at the H bond structure with the distance between the center of masses (CM) of the monomer being R(CM)=4.10 A with angles theta(A)=10 degrees, theta(B)=100 degrees and a well depth of 692.2 cm(-1), theta(A) is the angle the HBr bond of monomer A makes with the vector from the CM of A to the CM of B, and theta(B) is the corresponding angle monomer B makes with the same CM-CM vector. The barrier for the H interchange occurs at the closed C(2h) structure for which R(CM)=4.07 A, theta(A)=45 degrees, theta(B)=135 degrees, and the barrier height is 73.9 cm(-1). The PES was fitted using a linear-least squares method and the rovibrational energy levels of the complex were calculated by a split pseudospectral method. The spectroscopic data provide accurate molecular parameters for the dimer that are then compared with the results predicted on the basis of the 4-D ab initio PES. (c) 2004 American Institute of Physics.

  1. A four-dimensional motion field atlas of the tongue from tagged and cine magnetic resonance imaging

    Science.gov (United States)

    Xing, Fangxu; Prince, Jerry L.; Stone, Maureen; Wedeen, Van J.; El Fakhri, Georges; Woo, Jonghye

    2017-02-01

    Representation of human tongue motion using three-dimensional vector fields over time can be used to better understand tongue function during speech, swallowing, and other lingual behaviors. To characterize the inter-subject variability of the tongue's shape and motion of a population carrying out one of these functions it is desirable to build a statistical model of the four-dimensional (4D) tongue. In this paper, we propose a method to construct a spatio-temporal atlas of tongue motion using magnetic resonance (MR) images acquired from fourteen healthy human subjects. First, cine MR images revealing the anatomical features of the tongue are used to construct a 4D intensity image atlas. Second, tagged MR images acquired to capture internal motion are used to compute a dense motion field at each time frame using a phase-based motion tracking method. Third, motion fields from each subject are pulled back to the cine atlas space using the deformation fields computed during the cine atlas construction. Finally, a spatio-temporal motion field atlas is created to show a sequence of mean motion fields and their inter-subject variation. The quality of the atlas was evaluated by deforming cine images in the atlas space. Comparison between deformed and original cine images showed high correspondence. The proposed method provides a quantitative representation to observe the commonality and variability of the tongue motion field for the first time, and shows potential in evaluation of common properties such as strains and other tensors based on motion fields.

  2. Scapholunate kinematics of asymptomatic wrists in comparison with symptomatic contralateral wrists using four-dimensional CT examinations: initial clinical experience

    Energy Technology Data Exchange (ETDEWEB)

    Demehri, Shadpour; Hafezi-Nejad, Nima; Morelli, John N.; Thakur, Uma; Eng, John [Johns Hopkins University, Musculoskeletal Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Lifchez, Scott D.; Shores, Jaimie T. [Johns Hopkins University, Department of Plastic and Reconstructive Surgery, Baltimore, MD (United States); Means, Kenneth R. [MedStar Union Memorial Hospital, The Curtis National Hand Center, Baltimore, MD (United States)

    2016-04-15

    Using four-dimensional CT scan (4DCT), we aimed at showing the kinematics of scapholunate (SL) interval in asymptomatic wrists in comparison with symptomatic contralateral wrists with inconclusive radiographic findings. This is an IRB approved, HIPPA compliant, retrospective study. Patients suspected of SL interosseous ligament (SLIL) injuries were referred for further evaluation of chronic wrist pain (>3 months). Twelve wrists (11 subjects) with chronic symptoms and inconclusive plain radiographs and 10 asymptomatic wrists (in 10 different subjects) were scanned using 4DCT. The minimum SL interval was measured during three wrist motions: relaxed-to-clenched fist, flexion-to-extension, and radial-to-ulnar-deviation. Changes were recorded using double-oblique multiplanar reformation technique. We extracted the normal limits of the SL interval as measured by dynamic CT scanning during active motion in asymptomatic wrists. In asymptomatic wrists, the average SL interval was observed to be smaller than 1 mm during all motions. In symptomatic wrists, during exams performed with clenched fist (SL interval (mean ± SD) = 2.53 ± 1.19 mm), extension (2.54 ± 1.48 mm) or ulnar deviation (2.06 ± 1.12 mm), the average SL interval was more than 2 mm. In contrast to symptomatic wrists, no significant change in SL interval measurements was detected during wrist motions in asymptomatic wrists. There was a mild to moderate correlation between SL interval change and presence/absence of symptoms (point-biserial correlation coefficients: 0.29-0.55). In patients with wrist pain suspicious for SLIL injury and inconclusive radiographs, SL interval increase can be detected with 4DCT in the symptomatic wrist compared to the asymptomatic wrist. (orig.)

  3. Demand for radiotherapy in Spain.

    Science.gov (United States)

    Rodríguez, A; Borrás, J M; López-Torrecilla, J; Algara, M; Palacios-Eito, A; Gómez-Caamaño, A; Olay, L; Lara, P C

    2017-02-01

    Assessing the demand for radiotherapy in Spain based on existing evidence to estimate the human resources and equipment needed so that every person in Spain has access to high-quality radiotherapy when they need it. We used data from the European Cancer Observatory on the estimated incidence of cancer in Spain in 2012, along with the evidence-based indications for radiotherapy developed by the Australian CCORE project, to obtain an optimal radiotherapy utilisation proportion (OUP) for each tumour. About 50.5 % of new cancers in Spain require radiotherapy at least once over the course of the disease. Additional demand for these services comes from reradiation therapy and non-melanoma skin cancer. Approximately, 25-30 % of cancer patients with an indication for radiotherapy do not receive it due to factors that include access, patient preference, familiarity with the treatment among physicians, and especially resource shortages, all of which contribute to its underutilisation. Radiotherapy is underused in Spain. The increasing incidence of cancer expected over the next decade and the greater frequency of reradiations necessitate the incorporation of radiotherapy demand into need-based calculations for cancer services planning.

  4. Magnetic resonance imaging for assessment of parametrial tumour spread and regression patterns in adaptive cervix cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Maximilian P.; Fidarova, Elena [Dept. of Radiotherapy, Comprehensive Cancer Center, Medical Univ. of Vienna, Vienna (Austria)], e-mail: maximilian.schmid@akhwien.at; Poetter, Richard [Dept. of Radiotherapy, Comprehensive Cancer Center, Medical Univ. of Vienna, Vienna (Austria); Christian Doppler Lab. for Medical Radiation Research for Radiation Oncology, Medical Univ. of Vienna (Austria)] [and others

    2013-10-15

    Purpose: To investigate the impact of magnetic resonance imaging (MRI)-morphologic differences in parametrial infiltration on tumour response during primary radio chemotherapy in cervical cancer. Material and methods: Eighty-five consecutive cervical cancer patients with FIGO stages IIB (n = 59) and IIIB (n = 26), treated by external beam radiotherapy ({+-}chemotherapy) and image-guided adaptive brachytherapy, underwent T2-weighted MRI at the time of diagnosis and at the time of brachytherapy. MRI patterns of parametrial tumour infiltration at the time of diagnosis were assessed with regard to predominant morphology and maximum extent of parametrial tumour infiltration and were stratified into five tumour groups (TG): 1) expansive with spiculae; 2) expansive with spiculae and infiltrating parts; 3) infiltrative into the inner third of the parametrial space (PM); 4) infiltrative into the middle third of the PM; and 5) infiltrative into the outer third of the PM. MRI at the time of brachytherapy was used for identifying presence (residual vs. no residual disease) and signal intensity (high vs. intermediate) of residual disease within the PM. Left and right PM of each patient were evaluated separately at both time points. The impact of the TG on tumour remission status within the PM was analysed using {chi}2-test and logistic regression analysis. Results: In total, 170 PM were analysed. The TG 1, 2, 3, 4, 5 were present in 12%, 11%, 35%, 25% and 12% of the cases, respectively. Five percent of the PM were tumour-free. Residual tumour in the PM was identified in 19%, 68%, 88%, 90% and 85% of the PM for the TG 1, 2, 3, 4, and 5, respectively. The TG 3 - 5 had significantly higher rates of residual tumour in the PM in comparison to TG 1 + 2 (88% vs. 43%, p < 0.01). Conclusion: MRI-morphologic features of PM infiltration appear to allow for prediction of tumour response during external beam radiotherapy and chemotherapy. A predominantly infiltrative tumour spread at the

  5. A multi-institutional study to assess adherence to lung stereotactic body radiotherapy planning goals

    Energy Technology Data Exchange (ETDEWEB)

    Woerner, Andrew; Roeske, John C.; Harkenrider, Matthew M.; Campana, Maria; Surucu, Murat, E-mail: msurucu@lumc.edu [Loyola University Medical Center, Maywood, Illinois 60153 (United States); Fan, John [Edward Cancer Center, Naperville, Illinois 60540 (United States); Aydogan, Bulent; Koshy, Matthew [Department of Radiation Oncology, University of Illinois at Chicago, Chicago, Illinois 60612 (United States); Laureckas, Robert; Vali, Faisal [Advocate Christ Medical Center, Oak Lawn, Illinois 60453 (United States)

    2015-08-15

    Purpose: A multi-institutional planning study was performed to evaluate the frequency that current guidelines established by Radiation Therapy Oncology Group (RTOG) protocols and other literature for lung stereotactic body radiotherapy (SBRT) treatments are followed. Methods: A total of 300 patients receiving lung SBRT treatments in four different institutions were retrospectively reviewed. The treatments were delivered using Linac based SBRT (160 patients) or image guided robotic radiosurgery (140). Most tumors were located peripherally (250/300). Median fractional doses and ranges were 18 Gy (8–20 Gy), 12 Gy (6–15 Gy), and 10 Gy (5–12 Gy) for three, four, and five fraction treatments, respectively. The following planning criteria derived from RTOG trials and the literature were used to evaluate the treatment plans: planning target volumes, PTV{sub V} {sub 100} ≥ 95% and PTV{sub V} {sub 95} ≥ 99%; conformality indices, CI{sub 100%} < 1.2 and CI{sub 50%} range of 2.9–5.9 dependent on PTV; total lung-ITV: V{sub 20Gy} < 10%, V{sub 12.5Gy} < 15%, and V{sub 5Gy} < 37%; contralateral lung V{sub 5Gy} < 26%; and maximum doses for spinal cord, esophagus, trachea/bronchus, and heart and great vessels. Populations were grouped by number of fractions, and dosimetric criteria satisfaction rates (CSRs) were reported. Results: Five fraction regimens were the most common lung SBRT fractionation (46%). The median PTV was 27.2 cm{sup 3} (range: 3.8–419.5 cm{sup 3}). For all plans: mean PTV{sub V} {sub 100} was 94.5% (±5.6%, planning CSR: 69.8%), mean PTV{sub V} {sub 95} was 98.1% (±4.1%, CSR: 69.5%), mean CI{sub 100%} was 1.14 (±0.21, CSR: 79.1%, and 16.5% within minor deviation), and mean CI{sub 50%} was 5.63 (±2.8, CSR: 33.0%, and 28.0% within minor deviation). When comparing plans based on location, peripherally located tumors displayed higher PTV{sub V} {sub 100} and PTV{sub V} {sub 95} CSR (71.5% and 71.9%, respectively) than centrally located tumors (61

  6. Quality of life of women with breast cancer undergoing radiotherapy using the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire

    Directory of Open Access Journals (Sweden)

    Muszalik M

    2016-10-01

    Full Text Available Marta Muszalik,1 Małgorzata Kołucka-Pluta,2 Kornelia Kędziora-Kornatowska,1 Joanna Robaczewska1 1Department and Clinic of Geriatrics, Nicolaus Copernicus University, Collegium Medicum in Bydgoszcz, 2Centrum of Oncology in Bydgoszcz, Bydgoszcz, Poland Objective: Breast cancer is one of the most common cancers in women, particularly among older women. This illness along with its treatment has a great impact on a woman’s subjective opinion of her quality of life and functioning in everyday life. The aim of this research was to assess the quality of life in women undergoing radiotherapy for the treatment of breast cancer. Patients and methods: The research was carried out in 120 patients with breast cancer undergoing radiotherapy in the Oncological Center in Bydgoszcz, Poland. Among the 120 examined patients, there were 30 women aged between 20–50 years and the remaining were over 50 years of age, including 42 women over the age of 60. Demographic and clinical data were collected and the Functional Assessment of Chronic Illness Therapy-Fatigue questionnaire (version 4 was used to assess health-related quality of life (HRQOL of the patients. Statistical analyses were conducted using Statistica, version 10.0. Results: Patients with breast cancer undergoing radiotherapy rated their quality of life with an average of 113.83 points. Older patients above 71 years of age also displayed significantly higher HRQOL (122.70 points. A lower level of fatigue was noticed among patients ≤50 years and ≥71 years of age. Education and marital status also had an important impact on HRQOL. Educated women with a good financial situation had a significantly higher HRQOL, compared to those with a lower education and in poor living conditions. Conclusion: HRQOL and state of fatigue in breast cancer patients treated with radiotherapy depended upon their age. Both were high among women aged 71 years and above, while younger patients (51–70 years of age had

  7. To what extent does the anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) detect specific types of anxiety disorder in primary care? A psychometric study

    NARCIS (Netherlands)

    Terluin, B.; Oosterbaan, D.B.; Brouwers, E.P.; Straten, A. van; Ven, P.M. van de; Langerak, W.; Marwijk, H.W.J. van

    2014-01-01

    BACKGROUND: Anxiety scales may help primary care physicians to detect specific anxiety disorders among the many emotionally distressed patients presenting in primary care. The anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) consists of an admixture of symptoms of specific anxiety

  8. To what extent does the anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) detect specific types of anxiety disorder in primary care?

    NARCIS (Netherlands)

    Terluin, B.; Oosterbaan, D.B.; Brouwers, E.P.; van Straten, A.; van de Ven, P.M.; Langerak, W.; van Marwijk, H.W.

    2014-01-01

    Background: Anxiety scales may help primary care physicians to detect specific anxiety disorders among the many emotionally distressed patients presenting in primary care. The anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) consists of an admixture of symptoms of specific anxiety

  9. Four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) MR evaluation of the renal arteries in transplant recipients: Preliminary results.

    Science.gov (United States)

    Motoyama, Daisuke; Ishii, Yasuo; Takehara, Yasuo; Sugiyama, Masataka; Yang, Wang; Nasu, Hatsuko; Ushio, Takasuke; Hirose, Yuko; Ohishi, Naoki; Wakayama, Tetsuya; Kabasawa, Hiroyuki; Johnson, Kevin; Wieben, Oliver; Sakahara, Harumi; Ozono, Seiichiro

    2017-08-01

    To assess the performance of four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) at 3.0T in depicting intrarenal arteries compared with computed tomography angiography (CTA), and its correlation with arterial flowmetry in comparison with Doppler ultrasonography (DUS). In our prospective single-arm study, subjects were 25 patients who underwent renal transplant-related surgery at our hospital between July 2011 and June 2015. In the morphological study, depictions of renal artery branches delineated by magnetic resonance angiography (MRA)/4D PC-VIPR without gadolinium contrast agent were compared in seven living transplant recipients with the same kidney delineated by CTA in seven living transplant donors. In the flowmetric study, flow velocities in the renal (main stem), segmental, and interlobar arteries during systole and diastole were measured in 12 recipients using noncontrast MRA/4D PC-VIPR, and were compared with those obtained from DUS. Concerning MRA, average confidence levels of delineation rated by six observers for secondary to third level renal artery branches were 82.9-100% and for the fourth to fifth branches were 60.8-89.7% (average kappa value of 0.588 [95% confidence interval: 0.522-0.653]). Total flow velocities measured using 4D PC-VIPR and DUS demonstrated significant correlations during both systole and diastole with acceptable bias (r = 0.902; P < 0.001 in systole and r = 0.734; P < 0.001 in diastole). 4D PC-VIPR was useful in generating both morphological and hemodynamic information for evaluation of transplant intrarenal arteries without the need for contrast media. 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:595-603. © 2017 International Society for Magnetic Resonance in Medicine.

  10. Dosimetric study of a respiratory gating technique based on four-dimensional computed tomography in non-small-cell lung cancer

    Science.gov (United States)

    Lin, Hui; Lu, Heming; Shu, Liuyang; Huang, Huixian; Chen, Huasheng; Chen, Jiaxin; Cheng, Jinjian; Pang, Qiang; Peng, Luxing; Gu, Junzhao; Lu, Zhiping

    2014-01-01

    This study sought to compare the differences in target volumes and dose distributions to the targets and organs at risk (OARs) between a four-dimensional computed tomography (4DCT)-based respiratory-gated intensity-modulated radiation therapy (IMRT) plan (PlanEOE) and a three-dimensional CT (3DCT)-based IMRT plan (Plan3D) in patients with non-small-cell lung cancer (NSCLC). For 17 patients with Stages I–III NSCLC, both 4DCT data and conventional 3DCT data were obtained. The Plan3D and PlanEOE were designed based on 3DCT data and 4DCT data, respectively. The displacements of the gross tumor volume (GTV) centroid were 0.13 ± 0.09 cm, 0.15 ± 0.1 cm, and 0.27 ± 0.27 cm in the right–left, anterior–posterior, and superior–inferior directions, respectively. The volume of the GTVEOE was 3.05 ± 5.17 cm3 larger than that of the GTV3D. The volume of the PTV3D was 72.82 ± 48.65 cm3 larger than that of the PTVEOE. There was no significant difference between the PTV3D and PTVEOE for V55.8, V60, V66 and the homogeneity index. The PTV3D had a lower target conformity index than the PTVEOE (P = 0.036). PlanEOE had a significantly lower lung V10, V20, V30, V40 and mean lung dose (MLD) than Plan3D. For the heart, PlanEOE had a significantly lower V30 and mean dose. In conclusion, 4DCT is an appropriate method for assessing the displacement of the GTV centroid in three dimensions. PlanEOE has smaller PTVs and a decreased dose and volume for the normal lung and heart, as compared with Plan3D. PMID:24453355

  11. MR selective flow-tracking cartography: a postprocessing procedure applied to four-dimensional flow MR imaging for complete characterization of cranial dural arteriovenous fistulas.

    Science.gov (United States)

    Edjlali, Myriam; Roca, Pauline; Rabrait, Cécile; Trystram, Denis; Rodriguez-Régent, Christine; Johnson, Kevin M; Wieben, Oliver; Turski, Patrick; Meder, Jean-François; Naggara, Olivier; Oppenheim, Catherine

    2014-01-01

    To assess the feasibility of a selective flow-tracking cartographic procedure applied to four-dimensional (4D) flow imaging and to demonstrate its usefulness in the characterization of dural arteriovenous fistulas (DAVFs). Institutional review board approval was obtained, and all patients provided written informed consent. Eight patients (nine DAVFs) underwent 3.0-T magnetic resonance (MR) imaging and digital subtraction angiography (DSA). Imaging examinations were performed within 24 hours of each other. 4D flow MR imaging was performed by using a 4D radial phase-contrast vastly undersampled isotropic projection reconstruction pulse sequence with an isotropic spatial resolution of 0.86 mm (5 minutes 35 seconds). Two radiologists independently reviewed images from MR flow-tracking cartography and reported the location of arterial feeder vessels and the venous drainage type and classified DAVFs according to the risk of rupture (Cognard classification). These results were compared with those at DSA. Quadratic weighted κ statistics with their 95% confidence intervals (CIs) were used to test intermodality agreement in the identification of arterial feeder vessels, draining veins, and Cognard classification. Interreader agreement for shunt location on MR images was perfect (κ = 1), with good-to-excellent interreader agreement for arterial feeder vessel identification (κ = 0.97; 95% CI = 0.92, 1.0), and matched in all cases with shunt location defined at DSA. There was good-to-excellent agreement between MR cartography and DSA in the definition of the main feeding arteries (κ = 0.92; 95% CI = 0.83, 1.0), presence of retrograde flow in dural sinuses (κ = 1), presence of retrograde cortical venous drainage (κ = 1), presence of venous ectasia (κ = 1), and final Cognard classification of DAVFs (κ = 1, standard error = 0.35). MR selective flow-tracking cartography enabled the noninvasive characterization of cranial DAVFs. © RSNA, 2013.

  12. To what extent does the anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) detect specific types of anxiety disorder in primary care? A psychometric study

    Science.gov (United States)

    2014-01-01

    Background Anxiety scales may help primary care physicians to detect specific anxiety disorders among the many emotionally distressed patients presenting in primary care. The anxiety scale of the Four-Dimensional Symptom Questionnaire (4DSQ) consists of an admixture of symptoms of specific anxiety disorders. The research questions were: (1) Is the anxiety scale unidimensional or multidimensional? (2) To what extent does the anxiety scale detect specific DSM-IV anxiety disorders? (3) Which cut-off points are suitable to rule out or to rule in (which) anxiety disorders? Methods We analyzed 5 primary care datasets with standardized psychiatric diagnoses and 4DSQ scores. Unidimensionality was assessed through confirmatory factor analysis (CFA). We examined mean scores and anxiety score distributions per disorder. Receiver operating characteristic (ROC) analysis was used to determine optimal cut-off points. Results Total n was 969. CFA supported unidimensionality. The anxiety scale performed slightly better in detecting patients with panic disorder, agoraphobia, social phobia, obsessive compulsive disorder (OCD) and post traumatic stress disorder (PTSD) than patients with generalized anxiety disorder (GAD) and specific phobia. ROC-analysis suggested that ≥4 was the optimal cut-off point to rule out and ≥10 the cut-off point to rule in anxiety disorders. Conclusions The 4DSQ anxiety scale measures a common trait of pathological anxiety that is characteristic of anxiety disorders, in particular panic disorder, agoraphobia, social phobia, OCD and PTSD. The anxiety score detects the latter anxiety disorders to a slightly greater extent than GAD and specific phobia, without being able to distinguish between the different anxiety disorder types. The cut-off points ≥4 and ≥10 can be used to separate distressed patients in three groups with a relatively low, moderate and high probability of having one or more anxiety disorders. PMID:24761829

  13. Cross-cultural validation of the Turkish Four-Dimensional Symptom Questionnaire (4DSQ) using differential item and test functioning (DIF and DTF) analysis.

    Science.gov (United States)

    Terluin, Berend; Unalan, Pemra C; Turfaner Sipahioğlu, Nurver; Arslan Özkul, Seda; van Marwijk, Harm W J

    2016-05-11

    The Four-Dimensional Symptom Questionnaire (4DSQ) is originally a Dutch 50 item questionnaire developed in primary care to assess distress, depression, anxiety and somatization. We aimed to develop and validate a Turkish translation of the 4DSQ. The questionnaire was translated using forward and backward translation, and pilot testing. Turkish 4DSQ-data were collected in 352 consecutive adult primary care patients. For comparison, gender and age matched Dutch reference data were drawn from a larger existing dataset. We used differential item and test functioning (DIF and DTF) analysis to validate the Turkish translation to the original Dutch questionnaire. Through additional inquiry we tried to obtain more insight in the background of DIF in some items. Twenty-one items displayed DIF but this impacted only the distress and depression scores. Inquiry among Turkish people revealed that the reason for DTF in the distress scale was probably related to unfavourable socio-economic circumstances. On the other hand, the likely explanation for DTF in the depression scale appeared to be grounded in culturally and religiously determined optimistic beliefs. Raising the distress cut-offs by 2 points and lowering the depression cut-offs by 1 point ensures that individual Turkish 4DSQ scores be correctly interpreted. The Turkish translation of the 4DSQ (named: "Dört-Boyutlu Yakınma Listesi", 4BYL) measures the same constructs as the original Dutch questionnaire. Turkish anxiety and somatization scores can be interpreted in the same way as Dutch scores. However, when interpreting Turkish distress and depression scores, DTF should be taken into account.

  14. Four-dimensional distribution of the 2010 Eyjafjallajökull volcanic cloud over Europe observed by EARLINET

    Directory of Open Access Journals (Sweden)

    G. Pappalardo

    2013-04-01

    Full Text Available The eruption of the Icelandic volcano Eyjafjallajökull in April–May 2010 represents a "natural experiment" to study the impact of volcanic emissions on a continental scale. For the first time, quantitative data about the presence, altitude, and layering of the volcanic cloud, in conjunction with optical information, are available for most parts of Europe derived from the observations by the European Aerosol Research Lidar NETwork (EARLINET. Based on multi-wavelength Raman lidar systems, EARLINET is the only instrument worldwide that is able to provide dense time series of high-quality optical data to be used for aerosol typing and for the retrieval of particle microphysical properties as a function of altitude. In this work we show the four-dimensional (4-D distribution of the Eyjafjallajökull volcanic cloud in the troposphere over Europe as observed by EARLINET during the entire volcanic event (15 April–26 May 2010. All optical properties directly measured (backscatter, extinction, and particle linear depolarization ratio are stored in the EARLINET database available at http://www.earlinet.org. A specific relational database providing the volcanic mask over Europe, realized ad hoc for this specific event, has been developed and is available on request at http://www.earlinet.org. During the first days after the eruption, volcanic particles were detected over Central Europe within a wide range of altitudes, from the upper troposphere down to the local planetary boundary layer (PBL. After 19 April 2010, volcanic particles were detected over southern and south-eastern Europe. During the first half of May (5–15 May, material emitted by the Eyjafjallajökull volcano was detected over Spain and Portugal and then over the Mediterranean and the Balkans. The last observations of the event were recorded until 25 May in Central Europe and in the Eastern Mediterranean area. The 4-D distribution of volcanic aerosol layering and optical properties on

  15. Correlation of primary middle and distal esophageal cancers motion with surrounding tissues using four-dimensional computed tomography

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-06-01

    Full Text Available Wei Wang,1 Jianbin Li,1 Yingjie Zhang,1 Qian Shao,1 Min Xu,1 Bing Guo,1 Dongping Shang2 1Department of Radiation Oncology, 2Department of Big Bore CT Room, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, Shandong, People’s Republic of China Purpose: To investigate the correlation of gross tumor volume (GTV motion with the structure of interest (SOI motion and volume variation for middle and distal esophageal cancers using four-dimensional computed tomography (4DCT.Patients and methods: Thirty-three patients with middle or distal esophageal carcinoma underwent 4DCT simulation scan during free breathing. All image sets were registered with 0% phase, and the GTV, apex of diaphragm, lung, and heart were delineated on each phase of the 4DCT data. The position of GTV and SOI was identified in all 4DCT phases, and the volume of lung and heart was also achieved. The phase relationship between the GTV and SOI was estimated through Pearson’s correlation test.Results: The mean peak-to-peak displacement of all primary tumors in the lateral (LR, anteroposterior (AP, and superoinferior (SI directions was 0.13 cm, 0.20 cm, and 0.30 cm, respectively. The SI peak-to-peak motion of the GTV was defined as the greatest magnitude of motion. The displacement of GTV correlated well with heart in three dimensions and significantly associated with bilateral lung in LR and SI directions. A significant correlation was found between the GTV and apex of the diaphragm in SI direction (rleft=0.918 and rright=0.928. A significant inverse correlation was found between GTV motion and varying lung volume, but the correlation was not significant with heart (rLR=–0.530, rAP=–0.531, and rSI=–0.588 during respiratory cycle.Conclusion: For middle and distal esophageal cancers, GTV should expand asymmetric internal margins. The primary tumor motion has quite good correlation with diaphragm, heart, and lung. Keywords

  16. Four-dimensional variational inversion of black carbon emissions during ARCTAS-CARB with WRFDA-Chem

    Directory of Open Access Journals (Sweden)

    J. J. Guerrette

    2017-06-01

    Full Text Available Biomass burning emissions of atmospheric aerosols, including black carbon, are growing due to increased global drought, and comprise a large source of uncertainty in regional climate and air quality studies. We develop and apply new incremental four-dimensional variational (4D-Var capabilities in WRFDA-Chem to find optimal spatially and temporally distributed biomass burning (BB and anthropogenic black carbon (BC aerosol emissions. The constraints are provided by aircraft BC concentrations from the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites in collaboration with the California Air Resources Board (ARCTAS-CARB field campaign and surface BC concentrations from the Interagency Monitoring of PROtected Visual Environment (IMPROVE network on 22, 23, and 24 June 2008. We consider three BB inventories, including Fire INventory from NCAR (FINN v1.0 and v1.5 and Quick Fire Emissions Database (QFED v2.4r8. On 22 June, aircraft observations are able to reduce the spread between a customized QFED inventory and FINNv1.0 from a factor of 3. 5 ( × 3. 5 to only × 2. 1. On 23 and 24 June, the spread is reduced from × 3. 4 to × 1. 4. The posterior corrections to emissions are heterogeneous in time and space, and exhibit similar spatial patterns of sign for both inventories. The posterior diurnal BB patterns indicate that multiple daily emission peaks might be warranted in specific regions of California. The US EPA's 2005 National Emissions Inventory (NEI05 is used as the anthropogenic prior. On 23 and 24 June, the coastal California posterior is reduced by × 2, where highway sources dominate, while inland sources are increased near Barstow by × 5. Relative BB emission variances are reduced from the prior by up to 35 % in grid cells close to aircraft flight paths and by up to 60 % for fires near surface measurements. Anthropogenic variance reduction is as high as 40 % and is similarly

  17. SU-C-207-01: Four-Dimensional Inverse Geometry Computed Tomography: Concept and Its Validation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K; Kim, D; Kim, T; Kang, S; Cho, M; Shin, D; Suh, T [The Catholic University of Korea, Seoul (Korea, Republic of)

    2015-06-15

    Purpose: In past few years, the inverse geometry computed tomography (IGCT) system has been developed to overcome shortcomings of a conventional computed tomography (CT) system such as scatter problem induced from large detector size and cone-beam artifact. In this study, we intend to present a concept of a four-dimensional (4D) IGCT system that has positive aspects above all with temporal resolution for dynamic studies and reduction of motion artifact. Methods: Contrary to conventional CT system, projection data at a certain angle in IGCT was a group of fractionated narrow cone-beam projection data, projection group (PG), acquired from multi-source array which have extremely short time gap of sequential operation between each of sources. At this, for 4D IGCT imaging, time-related data acquisition parameters were determined by combining multi-source scanning time for collecting one PG with conventional 4D CBCT data acquisition sequence. Over a gantry rotation, acquired PGs from multi-source array were tagged time and angle for 4D image reconstruction. Acquired PGs were sorted into 10 phase and image reconstructions were independently performed at each phase. Image reconstruction algorithm based upon filtered-backprojection was used in this study. Results: The 4D IGCT had uniform image without cone-beam artifact on the contrary to 4D CBCT image. In addition, the 4D IGCT images of each phase had no significant artifact induced from motion compared with 3D CT. Conclusion: The 4D IGCT image seems to give relatively accurate dynamic information of patient anatomy based on the results were more endurable than 3D CT about motion artifact. From this, it will be useful for dynamic study and respiratory-correlated radiation therapy. This work was supported by the Industrial R&D program of MOTIE/KEIT [10048997, Development of the core technology for integrated therapy devices based on real-time MRI guided tumor tracking] and the Mid-career Researcher Program (2014R1A2A1A

  18. Four-dimensional variational inversion of black carbon emissions during ARCTAS-CARB with WRFDA-Chem

    Science.gov (United States)

    Guerrette, Jonathan J.; Henze, Daven K.

    2017-06-01

    Biomass burning emissions of atmospheric aerosols, including black carbon, are growing due to increased global drought, and comprise a large source of uncertainty in regional climate and air quality studies. We develop and apply new incremental four-dimensional variational (4D-Var) capabilities in WRFDA-Chem to find optimal spatially and temporally distributed biomass burning (BB) and anthropogenic black carbon (BC) aerosol emissions. The constraints are provided by aircraft BC concentrations from the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites in collaboration with the California Air Resources Board (ARCTAS-CARB) field campaign and surface BC concentrations from the Interagency Monitoring of PROtected Visual Environment (IMPROVE) network on 22, 23, and 24 June 2008. We consider three BB inventories, including Fire INventory from NCAR (FINN) v1.0 and v1.5 and Quick Fire Emissions Database (QFED) v2.4r8. On 22 June, aircraft observations are able to reduce the spread between a customized QFED inventory and FINNv1.0 from a factor of 3. 5 ( × 3. 5) to only × 2. 1. On 23 and 24 June, the spread is reduced from × 3. 4 to × 1. 4. The posterior corrections to emissions are heterogeneous in time and space, and exhibit similar spatial patterns of sign for both inventories. The posterior diurnal BB patterns indicate that multiple daily emission peaks might be warranted in specific regions of California. The US EPA's 2005 National Emissions Inventory (NEI05) is used as the anthropogenic prior. On 23 and 24 June, the coastal California posterior is reduced by × 2, where highway sources dominate, while inland sources are increased near Barstow by × 5. Relative BB emission variances are reduced from the prior by up to 35 % in grid cells close to aircraft flight paths and by up to 60 % for fires near surface measurements. Anthropogenic variance reduction is as high as 40 % and is similarly limited to sources close to observations. We

  19. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer.

    Science.gov (United States)

    Wang, Wei; Li, Jianbin; Zhang, Yingjie; Shao, Qian; Xu, Min; Fan, Tingyong; Wang, Jinzhi

    2016-01-01

    To investigate the definition of planning target volumes (PTVs) based on four-dimensional computed tomography (4DCT) compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathing. The motions of primary tumors located in the proximal (group A), middle (group B), and distal (group C) thoracic esophagus were obtained from the 4DCT scans. PTV3D was defined on 3DCT using the tumor motion measured based on 4DCT, PTV conventional (PTVconv) was defined on 3DCT by adding a 1.0 cm margin to the clinical target volume, and PTV4D was defined as the union of the target volumes contoured on the ten phases of the 4DCT images. The centroid positions, volumetric differences, and dice similarity coefficients were evaluated for all PTVs. The median centroid shifts between PTV3D and PTV4D and between PTVconv and PTV4D in all three dimensions were groups. The median size ratios of PTV4D to PTV3D were 0.80, 0.88, and 0.71, and PTV4D to PTVconv were 0.67, 0.73, and 0.76 (χ (2)=-3.18, -2.98, and -3.06; P=0.001, 0.003, and 0.002) for groups A, B, and C, respectively. The dice similarity coefficients were 0.87, 0.90, and 0.81 between PTV4D and PTV3D and 0.80, 0.84, and 0.83 between PTV4D and PTVconv (χ (2) =-3.18, -2.98, and -3.06; P=0.001, 0.003, and 0.002) for groups A, B, and C, respectively. The difference between the degree of inclusion of PTV4D in PTV3D and that of PTV4D in PTVconv was groups. Compared with PTVconv, the amount of irradiated normal tissue for PTV3D was decreased by 11.81% and 11.86% in groups A and B, respectively, but was increased by 2.93% in group C. For proximal and middle esophageal cancer, 3DCT-based PTV using asymmetrical margins provides good coverage of PTV4D; however, for distal esophageal cancer, 3DCT-based PTV using conventional margins provides ideal conformity with PTV4D.

  20. Improving thoracic four-dimensional cone-beam CT reconstruction with anatomical-adaptive image regularization (AAIR)

    Science.gov (United States)

    Shieh, Chun-Chien; Kipritidis, John; O'Brien, Ricky T.; Cooper, Benjamin J.; Kuncic, Zdenka; Keall, Paul J.

    2015-01-01

    Total-variation (TV) minimization reconstructions can significantly reduce noise and streaks in thoracic four-dimensional cone-beam computed tomography (4D CBCT) images compared to the Feldkamp-Davis-Kress (FDK) algorithm currently used in practice. TV minimization reconstructions are, however, prone to over-smoothing anatomical details and are also computationally inefficient. The aim of this study is to demonstrate a proof of concept that these disadvantages can be overcome by incorporating the general knowledge of the thoracic anatomy via anatomy segmentation into the reconstruction. The proposed method, referred as the anatomical-adaptive image regularization (AAIR) method, utilizes the adaptive-steepest-descent projection-onto-convex-sets (ASD-POCS) framework, but introduces an additional anatomy segmentation step in every iteration. The anatomy segmentation information is implemented in the reconstruction using a heuristic approach to adaptively suppress over-smoothing at anatomical structures of interest. The performance of AAIR depends on parameters describing the weighting of the anatomy segmentation prior and segmentation threshold values. A sensitivity study revealed that the reconstruction outcome is not sensitive to these parameters as long as they are chosen within a suitable range. AAIR was validated using a digital phantom and a patient scan and was compared to FDK, ASD-POCS and the prior image constrained compressed sensing (PICCS) method. For the phantom case, AAIR reconstruction was quantitatively shown to be the most accurate as indicated by the mean absolute difference and the structural similarity index. For the patient case, AAIR resulted in the highest signal-to-noise ratio (i.e. the lowest level of noise and streaking) and the highest contrast-to-noise ratios for the tumor and the bony anatomy (i.e. the best visibility of anatomical details). Overall, AAIR was much less prone to over-smoothing anatomical details compared to ASD-POCS and did

  1. Neurocognitive function impairment after whole brain radiotherapy for brain metastases: actual assessment

    Directory of Open Access Journals (Sweden)

    Tallet Agnes V

    2012-05-01

    Full Text Available Abstract Whole brain radiation therapy (WBRT is an effective treatment in brain metastases and, when combined with local treatments such as surgery and stereotactic radiosurgery, gives the best brain control. Nonetheless, WBRT is often omitted after local treatment due to its potential late neurocognitive effects. Publications on radiation-induced neurotoxicity have used different assessment methods, time to assessment, and definition of impairment, thus making it difficult to accurately assess the rate and magnitude of the neurocognitive decline that can be expected. In this context, and to help therapeutic decision making, we have conducted this literature review, with the aim of providing an average incidence, magnitude and time to occurrence of radio-induced neurocognitive decline. We reviewed all English language published articles on neurocognitive effects of WBRT for newly diagnosed brain metastases or with a preventive goal in adult patients, with any methodology (MMSE, battery of neurcognitive tests with which baseline status was provided. We concluded that neurocognitive decline is predominant at 4 months, strongly dependant on brain metastases control, partially solved at later time, graded 1 on a SOMA-LENT scale (only 8% of grade 2 and more, insufficiently assessed in long-term survivors, thus justifying all efforts to reduce it through irradiation modulation.

  2. Differentiation of Brain Tumor Recurrence from Post-Radiotherapy Necrosis with 11C-Methionine PET: Visual Assessment versus Quantitative Assessment.

    Directory of Open Access Journals (Sweden)

    Ryogo Minamimoto

    Full Text Available The aim of this multi-center study was to assess the diagnostic capability of visual assessment in L-methyl-11C-methionine positron emission tomography (MET-PET for differentiating a recurrent brain tumor from radiation-induced necrosis after radiotherapy, and to compare it to the accuracy of quantitative analysis.A total of 73 brain lesions (glioma: 31, brain metastasis: 42 in 70 patients who underwent MET-PET were included in this study. Visual analysis was performed by comparison of MET uptake in the brain lesion with MET uptake in one of four regions (around the lesion, contralateral frontal lobe, contralateral area, and contralateral cerebellar cortex. The concordance rate and logistic regression analysis were used to evaluate the diagnostic ability of visual assessment. Receiver-operating characteristic curve analysis was used to compare visual assessment with quantitative assessment based on the lesion-to-normal (L/N ratio of MET uptake.Interobserver and intraobserver κ-values were highest at 0.657 and 0.714, respectively, when assessing MET uptake in the lesion compared to that in the contralateral cerebellar cortex. Logistic regression analysis showed that assessing MET uptake in the contralateral cerebellar cortex with brain metastasis was significantly related to the final result. The highest area under the receiver-operating characteristic curve (AUC with visual assessment for brain metastasis was 0.85, showing no statistically significant difference with L/Nmax of the contralateral brain (AUC = 0.89 or with L/Nmean of the contralateral cerebellar cortex (AUC = 0.89, which were the areas that were the highest in the quantitative assessment. For evaluation of gliomas, no specific candidate was confirmed among the four areas used in visual assessment, and no significant difference was seen between visual assessment and quantitative assessment.The visual assessment showed no significant difference from quantitative assessment of MET

  3. Assessment of voluntary deep inspiration breath-hold with CINE imaging for breast radiotherapy.

    Science.gov (United States)

    Estoesta, Reuben Patrick; Attwood, Lani; Naehrig, Diana; Claridge-Mackonis, Elizabeth; Odgers, David; Martin, Darren; Pham, Melissa; Toohey, Joanne; Carroll, Susan

    2017-10-01

    Deep Inspiration Breath-Hold (DIBH) techniques for breast cancer radiation therapy (RT) have reduced cardiac dose compared to Free Breathing (FB). Recently, a voluntary deep inspiration breath-hold (vDIBH) technique was established using in-room lasers and skin tattoos to monitor breath-hold. An in-house quality assessment of positional reproducibility during RT delivery with vDIBH in patients with left-sided breast cancer was evaluated. The electronic portal imaging device (EPID) was used in cinematographic (CINE) mode to capture a sequence of images during beam delivery. Weekly CINE images were retrospectively assessed for 20 left-sided breast cancer patients receiving RT in vDIBH, and compared with CINE images of 20 patients treated in FB. The intra-beam motion was assessed and the distance from the beam central axis (CA) to the internal chest wall (ICW) was measured on each CINE image. These were then compared to the planned distance on digitally reconstructed radiograph (DRR). The maximum intra-beam motion for any one patient measurement was 0.30 cm for vDIBH and 0.20 cm for FB. The mean difference between the distance from the CA to ICW on DRR and the equivalent distance on CINE imaging (as treated) was 0.28 cm (SD 0.17) for vDIBH patients and 0.25 cm (SD 0.14) for FB patients (P = 0.458). The measured values were comparable for patients undergoing RT in vDIBH, and for those in FB. This quality assessment showed that using in-room lasers and skin tattoos to independently monitor breath-hold in vDIBH as detected by 'on-treatment' CINE imaging is safe and effective. © 2017 The Royal Australian and New Zealand College of Radiologists.

  4. 3D quantitative assessment of response to fractionated stereotactic radiotherapy and single-session stereotactic radiosurgery of vestibular schwannoma

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, T. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States); University Medical Center Hamburg-Eppendorf, Department of Diagnostic and Interventional Neuroradiology, Hamburg (Germany); Chapiro, J. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Lin, M. [Philips Research North America, Ultrasound Imaging and Interventions (UII), Briarcliff Manor, NY (United States); Geschwind, J.F. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Interventional Radiology, Baltimore, MD (United States); Yale University School of Medicine, Department of Radiology and Imaging Science, New Haven, CT (United States); Kleinberg, L. [The Johns Hopkins University School of Medicine, Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD (United States); Rigamonti, D.; Jusue-Torres, I.; Marciscano, A.E. [The Johns Hopkins University School of Medicine, Department of Neurological Surgery, Baltimore, MD (United States); Yousem, D.M. [The Johns Hopkins Hospital School of Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Division of Neuroradiology, Baltimore, MD (United States)

    2016-03-15

    To determine clinical outcome of patients with vestibular schwannoma (VS) after treatment with fractionated stereotactic radiotherapy (FSRT) and single-session stereotactic radiosurgery (SRS) by using 3D quantitative response assessment on MRI. This retrospective analysis included 162 patients who underwent radiation therapy for sporadic VS. Measurements on T1-weighted contrast-enhanced MRI (in 2-year post-therapy intervals: 0-2, 2-4, 4-6, 6-8, 8-10, 10-12 years) were taken for total tumour volume (TTV) and enhancing tumour volume (ETV) based on a semi-automated technique. Patients were considered non-responders (NRs) if they required subsequent microsurgical resection or developed radiological progression and tumour-related symptoms. Median follow-up was 4.1 years (range: 0.4-12.0). TTV and ETV decreased for both the FSRT and SRS groups. However, only the FSRT group achieved significant tumour shrinkage (p < 0.015 for TTV, p < 0.005 for ETV over time). The 11 NRs showed proportionally greater TTV (median TTV pre-treatment: 0.61 cm{sup 3}, 8-10 years after: 1.77 cm{sup 3}) and ETV despite radiation therapy compared to responders (median TTV pre-treatment: 1.06 cm{sup 3}; 10-12 years after: 0.81 cm{sup 3}; p = 0.001). 3D quantification of VS showed a significant decrease in TTV and ETV on FSRT-treated patients only. NR had significantly greater TTV and ETV over time. (orig.)

  5. Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

    Directory of Open Access Journals (Sweden)

    Wang W

    2016-08-01

    Full Text Available Wei Wang, Jianbin Li, Yingjie Zhang, Qian Shao, Min Xu, Tingyong Fan, Jinzhi Wang Department of Radiation Oncology, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Shandong, People’s Republic of China Background and purpose: To investigate the definition of planning target volumes (PTVs based on four-dimensional computed tomography (4DCT compared with conventional PTV definition and PTV definition using asymmetrical margins for thoracic primary esophageal cancer. Materials and methods: Forty-three patients with esophageal cancer underwent 3DCT and 4DCT simulation scans during free breathing. The motions of primary tumors located in the proximal (group A, middle (group B, and distal (group C thoracic esophagus were obtained from the 4DCT scans. PTV3D was defined on 3DCT using the tumor motion measured based on 4DCT, PTV conventional (PTVconv was defined on 3DCT by adding a 1.0 cm margin to the clinical target volume, and PTV4D was defined as the union of the target volumes contoured on the ten phases of the 4DCT images. The centroid positions, volumetric differences, and dice similarity coefficients were evaluated for all PTVs. Results: The median centroid shifts between PTV3D and PTV4D and between PTVconv and PTV4D in all three dimensions were <0.3 cm for the three groups. The median size ratios of PTV4D to PTV3D were 0.80, 0.88, and 0.71, and PTV4D to PTVconv were 0.67, 0.73, and 0.76 (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The dice similarity coefficients were 0.87, 0.90, and 0.81 between PTV4D and PTV3D and 0.80, 0.84, and 0.83 between PTV4D and PTVconv (χ2=–3.18, –2.98, and –3.06; P=0.001, 0.003, and 0.002 for groups A, B, and C, respectively. The difference between the degree of inclusion of PTV4D in PTV3D and that of PTV4D in PTVconv was <2% for all groups. Compared with PTVconv, the amount of irradiated normal tissue

  6. Four-dimensional dose reconstruction through in vivo phase matching of cine images of electronic portal imaging device.

    Science.gov (United States)

    Yoon, Jihyung; Jung, Jae Won; Kim, Jong Oh; Yi, Byong Yong; Yeo, Inhwan

    2016-07-01

    A method is proposed to reconstruct a four-dimensional (4D) dose distribution using phase matching of measured cine images to precalculated images of electronic portal imaging device (EPID). (1) A phantom, designed to simulate a tumor in lung (a polystyrene block with a 3 cm diameter embedded in cork), was placed on a sinusoidally moving platform with an amplitude of 1 cm and a period of 4 s. Ten-phase 4D computed tomography (CT) images of the phantom were acquired. A planning target volume (PTV) was created by adding a margin of 1 cm around the internal target volume of the tumor. (2) Three beams were designed, which included a static beam, a theoretical dynamic beam, and a planning-optimized dynamic beam (PODB). While the theoretical beam was made by manually programming a simplistic sliding leaf motion, the planning-optimized beam was obtained from treatment planning. From the three beams, three-dimensional (3D) doses on the phantom were calculated; 4D dose was calculated by means of the ten phase images (integrated over phases afterward); serving as "reference" images, phase-specific EPID dose images under the lung phantom were also calculated for each of the ten phases. (3) Cine EPID images were acquired while the beams were irradiated to the moving phantom. (4) Each cine image was phase-matched to a phase-specific CT image at which common irradiation occurred by intercomparing the cine image with the reference images. (5) Each cine image was used to reconstruct dose in the phase-matched CT image, and the reconstructed doses were summed over all phases. (6) The summation was compared with forwardly calculated 4D and 3D dose distributions. Accounting for realistic situations, intratreatment breathing irregularity was simulated by assuming an amplitude of 0.5 cm for the phantom during a portion of breathing trace in which the phase matching could not be performed. Intertreatment breathing irregularity between the time of treatment and the time of planning CT was

  7. Synchronization and Electronic Circuit Application of Hidden Hyperchaos in a Four-Dimensional Self-Exciting Homopolar Disc Dynamo without Equilibria

    Directory of Open Access Journals (Sweden)

    Yu Feng

    2017-01-01

    Full Text Available We introduce and investigate a four-dimensional hidden hyperchaotic system without equilibria, which is obtained by augmenting the three-dimensional self-exciting homopolar disc dynamo due to Moffatt with an additional control variable. Synchronization of two such coupled disc dynamo models is investigated by active control and sliding mode control methods. Numerical integrations show that sliding mode control provides a better synchronization in time but causes chattering. The solution is obtained by switching to active control when the synchronization errors become very small. In addition, the electronic circuit of the four-dimensional hyperchaotic system has been realized in ORCAD-PSpice and on the oscilloscope by amplitude values, verifying the results from the numerical experiments.

  8. Late Effects of Head and Neck Radiotherapy on Pulp Vitality Assessed by Pulse Oximetry.

    Science.gov (United States)

    Kataoka, Simony Hidee Hamoy; Setzer, Frank C; Gondim-Junior, Eudes; Fregnani, Eduardo Rodrigues; Moraes, Claudia Joffily P; Pessoa, Oscar Faciola; Gavini, Giulio; Caldeira, Celso Luiz

    2016-06-01

    Radiation therapy (RT) of malignant tumors in the head and neck area may have damaging effects on surrounding tissues. The aim of this investigation was to evaluate the long-term effects of ionizing radiation on pulp vitality by measuring pulp oxygenation levels (%SpO2) in patients with history of RT of intraoral and oropharyngeal tumors 4-6 years after treatment. In an experimental group RT (n = 90, history of RT) and a control group CON (n = 90, no history of RT), pulp vitality was assessed by measuring %SpO2 by using pulse oximetry and pulp sensitivity by cold thermal testing. All anterior teeth without history of endodontic therapy of the participants in group RT were measured (n = 693), regardless of the quadrant and the irradiated area. An equal number of anterior teeth were tested in group CON. There was no significant difference between the %SpO2 levels in group RT (92.7%; standard deviation, ± 1.83) and group CON (92.6%; standard deviation, ± 1.80). All teeth in RT and CON groups showed a positive response to the thermal test. All tested teeth were considered vital. Pulp %SpO2 was found to be within normal limits 4-6 years after RT. This suggests that RT may not have a long-term influence on pulp vitality, and reported short-term changes in pulpal microcirculation because of RT may be temporary. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  9. Tumor Shrinkage Assessed by Volumetric MRI in Long-Term Follow-Up After Fractionated Stereotactic Radiotherapy of Nonfunctioning Pituitary Adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Kopp, Christine, E-mail: Christine.Kopp@lrz.tu-muenchen.de [Klinik und Poliklinik fuer Strahlentherapie und Radiologische Onkologie, Klinikum rechts der Isar, Technische Universitaet Muenchen, Munich (Germany); Theodorou, Marilena; Poullos, Nektarios; Jacob, Vesna; Astner, Sabrina T.; Molls, Michael [Klinik und Poliklinik fuer Strahlentherapie und Radiologische Onkologie, Klinikum rechts der Isar, Technische Universitaet Muenchen, Munich (Germany); Grosu, Anca-Ligia [Klinik fuer Strahlenheilkunde, Universitaet Freiburg, Freiburg (Germany)

    2012-03-01

    Purpose: To evaluate tumor control and side effects associated with fractionated stereotactic radiotherapy (FSRT) in the management of residual or recurrent nonfunctioning pituitary adenomas (NFPAs). Methods and Materials: We assessed exact tumor volume shrinkage in 16 patients with NFPA after FSRT. All patients had previously undergone surgery. Gross tumor volume (GTV) was outlined on contrast-enhanced magnetic resonance imaging (MRI) before and median 63 months (range, 28-100 months) after FSRT. MRI was performed as an axial three-dimensional gradient echo T1-weighted sequence at 1.6-mm slice thickness without gap (3D MRI). Results: Mean tumor size of all 16 pituitary adenomas before treatment was 7.4 mL (3.3-18.9 mL). We found shrinkage of the treated pituitary adenoma in all patients. Within a median follow-up of 63 months (28-100 months) an absolute mean volume reduction of 3.8 mL (0.9-12.4 mL) was seen. The mean relative size reduction compared with the volume before radiotherapy was 51% (22%-95%). Shrinkage measured by 3D MRI was greater at longer time intervals after radiotherapy. A strong negative correlation between the initial tumor volume and the absolute volume reduction after FSRT was found. There was no correlation between tumor size reduction and patient age, sex, or number of previous surgeries. Conclusions: By using 3D MRI in all patients undergoing FSRT of an NFPA, tumor shrinkage is detected. Our data demonstrate that volumetric assessment based on 3D MRI adds additional information to routinely used radiological response measurements. After FSRT a mean relative size reduction of 51% can be expected within 5 years.

  10. Postmastectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shikama, Naoto; Koguchi, Masahiko; Sasaki, Shigeru; Kaneko, Tomoki; Shinoda, Atsunori; Nishikawa, Atsushi [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

    2000-10-01

    Since there have been few reports on postmastectomy radiotherapy having a high evidence level in Japan, the significance of postoperative radiotherapy and the irradiation techniques were reviewed based on reports from Western countries. Authors focused on the indications for postoperative irradiation, irradiation methods (irradiation sites, irradiation techniques; prosthetics, methods of irradiating the chest wall and lymph nodes, timing of irradiation), and complications, and discuss them. The factors thought to be adaptable to postmastectomy radiotherapy have been listed. Axillary lymph node metastasis and the size of the primary focus are thought to be important factors in locoregional recurrence. The chest wall and the supraclavicular lymph nodes are the usual sites of irradiation after mastectomy. The irradiation method consists of tangential irradiation of the chest wall and single-field irradiation of the supraclavicular lymph nodes, with 46-50 Gy in fractional doses of 1.8-2 Gy x 5/w is administered for 4.5-5.5 weeks. The timing of irradiation in the West is generally after chemotherapy. Adverse radiation effects include ischemic heart disease, pneumonitis, arm edema, rib fractures, and brachial plexus paralysis. The frequency of these complications is increased by the combined use of chemotherapy or surgery. The breast cancer cure rate in Japan is generally better than in the West. It remains to be determined whether the clinical data from Europe and America are applicable to the treatment of breast cancer in Japan. To address this issue, a clinical investigation should be performed in Japan with close cooperation between surgeons, physicians, pathologists, and radiotherapists. (K.H.)

  11. The effect of radiotherapy, and radiotherapy combined with bisphosphonates or RANK ligand inhibitors on bone quality in bone metastases. A systematic review

    NARCIS (Netherlands)

    Groenen, K.H.; Pouw, M.H.; Hannink, G.J.; Hosman, A.J.; Linden, Y.M. van der; Verdonschot, N.J.; Tanck, E.J.

    2016-01-01

    PURPOSE: The role of radiotherapy in stabilizing metastatic bones is unclear. This systematic review assessed the effects of (1) radiotherapy, (2) radiotherapy combined with bisphosphonates, and (3) radiotherapy combined with RANK ligand (RANKL) inhibitors on bone quality and bone strength in bone

  12. The effect of radiotherapy, and radiotherapy combined with bisphosphonates or RANK ligand inhibitors on bone quality in bone metastases. A systematic review

    NARCIS (Netherlands)

    Groenen, K.H.J.; Pouw, M.H.; Hannink, G.; Hosman, A.J.; van der Linden, Y.M.; Verdonschot, Nicolaas Jacobus Joseph; Tanck, E.

    2016-01-01

    Purpose The role of radiotherapy in stabilizing metastatic bones is unclear. This systematic review assessed the effects of (1) radiotherapy, (2) radiotherapy combined with bisphosphonates, and (3) radiotherapy combined with RANK ligand (RANKL) inhibitors on bone quality and bone strength in bone

  13. Evaluation of novel radiotherapy technologies: what evidence is needed to assess their clinical and cost effectiveness, and how should we get it?

    NARCIS (Netherlands)

    Loon, J. van; Grutters, J.P.C.; Macbeth, F.

    2012-01-01

    Technical innovations in radiation oncology--eg, intensity-modulated radiotherapy, stereotactic radiotherapy, and particle therapy--can be developed rapidly and introduced into the clinic even when costs associated with their use are much higher than those for conventional radiotherapy. Although

  14. Assessment of the perfusion of glioblastomas before and during radiotherapy: longitudinal comparison between H{sub 2}-{sup 15}O positron emission tomography and perfusion MRI; Evaluation de la perfusion des glioblastomes en avant et pendant la radiotherapie: comparaison longitudinale entre la tomographie par emission de positons H2 15O et l'IRM de perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Laprie, A.; Ken, S.; Moyal Cohen-Jonathan, E. [Departement de radiotherapie, institut Claudius-Regaud, 31 - Toulouse (France); Laprie, A.; Ken, S.; Lotterie, J.A.; Franceries, X.; Celsis, P.; Payoux, P.; Berry, I. [Inserm imagerie cerebrale et handicaps neurologiques UMR 825, 31 - Toulouse (France); Lotterie, J.A.; Berry, I. [Departement de biophysique, centre hospitalier universitaire de Rangueil, 31 - Toulouse (France); Barcelo, C. [Departement de radiologie, centre hospitalier universitaire de Purpan, 31 - Toulouse (France)

    2010-10-15

    The authors report the comparison of different perfusion imagery modalities for patients suffering form glioblastomas and included in a phase-1 clinic trial comprising conformational radiotherapy concomitant with the use of a farnesyl-transferase inhibitor (tipifarnib). With these different techniques, perfusion MRI and perfusion positron emission tomography, the authors made respectively a qualitative and quantitative assessment of the tumour vascularisation. Short communication

  15. Exactly solvable quantum few-body systems associated with the symmetries of the three-dimensional and four-dimensional icosahedra

    Directory of Open Access Journals (Sweden)

    T. Scoquart, J. J. Seaward, S. G. Jackson, M. Olshanii

    2016-10-01

    Full Text Available The purpose of this article is to demonstrate that non-crystallographic reflection groups can be used to build new solvable quantum particle systems. We explicitly construct a one-parametric family of solvable four-body systems on a line, related to the symmetry of a regular icosahedron: in two distinct limiting cases the system is constrained to a half-line. We repeat the program for a 600-cell, a four-dimensional generalization of the regular three-dimensional icosahedron.

  16. Continuous table acquisition MRI for radiotherapy treatment planning: Distortion assessment with a new extended 3D volumetric phantom

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Amy, E-mail: aw554@uowmail.edu.au; Metcalfe, Peter [Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia and Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute for Applied Medical Research, Liverpool, NSW 2170 (Australia); Liney, Gary [Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute for Applied Medical Research, Liverpool, NSW 2170 (Australia); South West Clinical School, University of New South Wales, Sydney, NSW 2170 (Australia); Holloway, Lois [Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute for Applied Medical Research, Liverpool, NSW 2170 (Australia); South West Clinical School, University of New South Wales, Sydney, NSW 2170 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Dowling, Jason; Rivest-Henault, David [Commonwealth Scientific and Industrial Research Organisation, Australian E-Health Research Centre, Herston, QLD 4029 (Australia)

    2015-04-15

    Purpose: Accurate geometry is required for radiotherapy treatment planning (RTP). When considering the use of magnetic resonance imaging (MRI) for RTP, geometric distortions observed in the acquired images should be considered. While scanner technology and vendor supplied correction algorithms provide some correction, large distortions are still present in images, even when considering considerably smaller scan lengths than those typically acquired with CT in conventional RTP. This study investigates MRI acquisition with a moving table compared with static scans for potential geometric benefits for RTP. Methods: A full field of view (FOV) phantom (diameter 500 mm; length 513 mm) was developed for measuring geometric distortions in MR images over volumes pertinent to RTP. The phantom consisted of layers of refined plastic within which vitamin E capsules were inserted. The phantom was scanned on CT to provide the geometric gold standard and on MRI, with differences in capsule location determining the distortion. MRI images were acquired with two techniques. For the first method, standard static table acquisitions were considered. Both 2D and 3D acquisition techniques were investigated. With the second technique, images were acquired with a moving table. The same sequence was acquired with a static table and then with table speeds of 1.1 mm/s and 2 mm/s. All of the MR images acquired were registered to the CT dataset using a deformable B-spline registration with the resulting deformation fields providing the distortion information for each acquisition. Results: MR images acquired with the moving table enabled imaging of the whole phantom length while images acquired with a static table were only able to image 50%–70% of the phantom length of 513 mm. Maximum distortion values were reduced across a larger volume when imaging with a moving table. Increased table speed resulted in a larger contribution of distortion from gradient nonlinearities in the through

  17. Evaluation of various approaches for assessing dose indicators and patient organ doses resulting from radiotherapy cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Rampado, Osvaldo, E-mail: orampado@cittadellasalute.to.it; Giglioli, Francesca Romana; Rossetti, Veronica; Ropolo, Roberto [Struttura Complessa Fisica Sanitaria, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Corso Bramante 88, Torino 10126 (Italy); Fiandra, Christian; Ragona, Riccardo [Radiation Oncology Department, University of Turin, Torino 10126 (Italy)

    2016-05-15

    Purpose: The aim of this study was to evaluate various approaches for assessing patient organ doses resulting from radiotherapy cone-beam CT (CBCT), by the use of thermoluminescent dosimeter (TLD) measurements in anthropomorphic phantoms, a Monte Carlo based dose calculation software, and different dose indicators as presently defined. Methods: Dose evaluations were performed on a CBCT Elekta XVI (Elekta, Crawley, UK) for different protocols and anatomical regions. The first part of the study focuses on using PCXMC software (PCXMC 2.0, STUK, Helsinki, Finland) for calculating organ doses, adapting the input parameters to simulate the exposure geometry, and beam dose distribution in an appropriate way. The calculated doses were compared to readouts of TLDs placed in an anthropomorphic Rando phantom. After this validation, the software was used for analyzing organ dose variability associated with patients’ differences in size and gender. At the same time, various dose indicators were evaluated: kerma area product (KAP), cumulative air-kerma at the isocenter (K{sub air}), cone-beam dose index, and central cumulative dose. The latter was evaluated in a single phantom and in a stack of three adjacent computed tomography dose index phantoms. Based on the different dose indicators, a set of coefficients was calculated to estimate organ doses for a range of patient morphologies, using their equivalent diameters. Results: Maximum organ doses were about 1 mGy for head and neck and 25 mGy for chest and pelvis protocols. The differences between PCXMC and TLDs doses were generally below 10% for organs within the field of view and approximately 15% for organs at the boundaries of the radiation beam. When considering patient size and gender variability, differences in organ doses up to 40% were observed especially in the pelvic region; for the organs in the thorax, the maximum differences ranged between 20% and 30%. Phantom dose indexes provided better correlation with organ

  18. Changes in Tumor Volumes and Spatial Locations Relative to Normal Tissues During Cervical Cancer Radiotherapy Assessed by Cone Beam Computed Tomography.

    Science.gov (United States)

    Chen, Wenjuan; Bai, Penggang; Pan, Jianji; Xu, Yuanji; Chen, Kaiqiang

    2017-04-01

    To assess changes in the volumes and spatial locations of tumors and surrounding organs by cone beam computed tomography during treatment for cervical cancer. Sixteen patients with cervical cancer had intensity-modulated radiotherapy and off-line cone beam computed tomography during chemotherapy and/or radiation therapy. The gross tumor volume (GTV-T) and clinical target volumes (CTVs) were contoured on the planning computed tomography and weekly cone beam computed tomography image, and changes in volumes and spatial locations were evaluated using the volume difference method and Dice similarity coefficients. The GTV-T was 79.62 cm3 at prior treatment (0f) and then 20.86 cm3 at the end of external-beam chemoradiation. The clinical target volume changed slightly from 672.59 cm3 to 608.26 cm3, and the uterine volume (CTV-T) changed slightly from 83.72 cm3 to 80.23 cm3. There were significant differences in GTV-T and CTV-T among the different groups ( P .05). The mean percent volume changes ranged from 23.05% to 70.85% for GTV-T, 4.71% to 6.78% for CTV-T, and 5.84% to 9.59% for clinical target volume, and the groups were significantly different ( P < .05). The Dice similarity coefficient of GTV-T decreased during the course of radiation therapy ( P < .001). In addition, there were significant differences in GTV-T among different groups ( P < .001), and changes in GTV-T correlated with the radiotherapy ( P < .001). There was a negative correlation between volume change rate (DV) and Dice similarity coefficient in the GTV-T and organs at risk ( r < 0; P < .05). The volume, volume change rate, and Dice similarity coefficient of GTV-T were all correlated with increase in radiation treatment. Significant variations in tumor regression and spatial location occurred during radiotherapy for cervical cancer. Adaptive radiotherapy approaches are needed to improve the treatment accuracy for cervical cancer.

  19. Assessment of dosimetric impact of system specific geometric distortion in an MRI only based radiotherapy workflow for prostate

    Science.gov (United States)

    Gustafsson, C.; Nordström, F.; Persson, E.; Brynolfsson, J.; Olsson, L. E.

    2017-04-01

    Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system. To simulate the distortion aspects of a synthetic CT (electron density derived from MR images), the displacement map was applied to CT images, referred to as distorted CT images. A volumetric modulated arc prostate treatment plan was applied to the original CT and the distorted CT, creating a reference and a distorted CT dose distribution. By applying the inverse of the displacement map to the distorted CT dose distribution, a dose distribution in the same geometry as the original CT images was created. For 10 prostate cancer patients, the dose difference between the reference dose distribution and inverse distorted CT dose distribution was analyzed in isodose level bins. The mean magnitude of the geometric distortion was 1.97 mm for the radial distance of 200-250 mm from isocenter. The mean percentage dose differences for all isodose level bins, were  ⩽0.02% and the radiotherapy structure mean volume deviations were  prostate MRI only radiotherapy workflow, separated from dosimetric effects originating from synthetic CT generation. No clinically relevant dose difference or structure deformation was found when 3D distortion correction and high acquisition bandwidth was used. The method could be used for any MRI sequence together with any anatomy of interest.

  20. Patient assessed symptoms are poor predictors of objective findings. Results from a cross sectional study in patients treated with radiotherapy for pharyngeal cancer

    DEFF Research Database (Denmark)

    Jensen, Kenneth; Lambertsen, Karin; Torkov, Peter

    2007-01-01

    Introduction. The aim of the study was to assess the value of the EORTC questionnaires C30 and H&N35, as an instrument for the study of side effects. Patients and methods. We invited all recurrence free patients, treated with radical radiotherapy for pharyngeal cancer between 1998 and 2002 at our...... institution, to participate in the study. Data was retrieved using questionnaires, functional endoscopic evaluation of swallowing, dental examination with orthopantomography and saliva flow measurements. Thirty-five (55% of invited) participated. Results. Side effects were omnipresent and often severe....... The value of patient assessed symptom scores to predict equivalent objective changes was varied: We found a sensitivity of 0.59-0.93, specificity of 0.40-0.81, positive predictive value of 0.28-0.81 and a negative predictive value of 0.46-0.94. Conclusion. The questionnaire should be used to retrieve...

  1. Nonlinear spatio-temporal filtering of dynamic PET data using a four-dimensional Gaussian filter and expectation-maximization deconvolution.

    Science.gov (United States)

    Floberg, J M; Holden, J E

    2013-02-21

    We introduce a method for denoising dynamic PET data, spatio-temporal expectation-maximization (STEM) filtering, that combines four-dimensional Gaussian filtering withEMdeconvolution. The initial Gaussian filter suppresses noise at a broad range of spatial and temporal frequencies and EM deconvolution quickly restores the frequencies most important to the signal. We aim to demonstrate that STEM filtering can improve variance in both individual time frames and in parametric images without introducing significant bias. We evaluate STEM filtering with a dynamic phantom study, and with simulated and human dynamic PET studies of a tracer with reversible binding behaviour, [C-11]raclopride, and a tracer with irreversible binding behaviour, [F-18]FDOPA. STEM filtering is compared to a number of established three and four-dimensional denoising methods. STEM filtering provides substantial improvements in variance in both individual time frames and in parametric images generated with a number of kinetic analysis techniques while introducing little bias. STEM filtering does bias early frames, but this does not affect quantitative parameter estimates. STEM filtering is shown to be superior to the other simple denoising methods studied. STEM filtering is a simple and effective denoising method that could be valuable for a wide range of dynamic PET applications.

  2. Management of radiotherapy-induced skin reactions.

    Science.gov (United States)

    Trueman, Ellen

    2015-04-01

    Radiotherapy is a highly effective cancer treatment that not only offers cure but also excellent palliation of disease related symptoms and complications. Although radiotherapy is primarily an outpatient treatment, delivered within specialist centres, a diverse range of health professionals may be involved in the treatment pathway before, during and after treatment. Radiotherapy can, and does, make a significant contribution to improving a patient's wellbeing through effective symptom management. However, treatment-related side-effects do occur, with an acute skin reaction being one of the most common. It is imperative that radiotherapy-induced skin reactions are correctly assessed and appropriately managed in promoting patient comfort, treatment compliance and enhanced quality of life. This article describes how the use of a recognised assessment tool and evidence-based guidelines can facilitate consistent, high-quality care in the management of radiotherapy-induced skin reactions.

  3. Pre-therapeutic nutritional assessment for predicting severe adverse events in patients with head and neck cancer treated by radiotherapy.

    Science.gov (United States)

    Kono, Takeyuki; Sakamoto, Koji; Shinden, Seiichi; Ogawa, Kaoru

    2017-12-01

    Malnutrition is common in patients with head and neck cancer (HNSCC). It may be related to severe adverse toxicity as a result of radiotherapy. The aim was to investigate nutritional screening factors for severe adverse events. A retrospective chart review of 101 patients who underwent radiotherapy from 2009 to 2013 was performed. The relationships among severe adverse events and pretreatment nutritional parameters, including static variables (serum albumin, total protein, total lymphocyte counts, body mass index), dynamic variables (retinol-binding protein, transferrin, pre-albumin), and nutritional screening tools (Onodera's Prognostic Nutrition Index [O-PNI]; Nutrition Risk Index; Controlling Nutritional Status [CONUT] score; Nutritional Risk Screening 2002) were evaluated in addition to patient and treatment factors. According to the static parameters, approximately 30% of patients were malnourished before treatment. Twenty-four patients exhibited severe adverse events. On univariate analysis, combined chemotherapy, advanced staging, O-PNI nutritional factor for predicting severe adverse events in HNSCC patients undergoing chemoradiotherapy and facilitates the planning of aggressive nutritional interventions prior to treatment. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  4. Combination of radiotherapy and double blockade HER2 with pertuzumab and trastuzumab for HER2-positive metastatic or locally recurrent unresectable and/or metastatic breast cancer: Assessment of early toxicity.

    Science.gov (United States)

    Ajgal, Z; de Percin, S; Diéras, V; Pierga, J Y; Campana, F; Fourquet, A; Kirova, Y M

    2017-04-01

    We evaluate the early toxicity of concurrent use of radiotherapy, pertuzumab and trastuzumab in patients with HER2-positive metastatic or locally recurrent unresectable breast cancer. A retrospective study was performed in a population of 23 consecutive patients between 2013 and 2015. Radiotherapy was performed on the chest area or metastatic sites during maintenance with pertuzumab and trastuzumab after six cycles of pertuzumab, trastuzumab and docetaxel. Toxicity was assessed according to the National Cancer Institute Common Toxicity Criteria version 4. Irradiation volumes were whole breast (8 patients) and chest wall (9 patients) at 50Gy in 25 fractions, the supraclavicular nodes (16 patients), the axillary area (nine patients) and the internal mammary nodes (9 patients) at 46Gy in 23 fractions. For five patients, radiotherapy was palliative: bone irradiation (4 patients), whole brain radiotherapy (one patient). Median follow-up was 12.6 months (range: 6.1-21.6 months) since the start of pertuzumab and trastuzumab. One patient presented an asymptomatic decrease of left ventricular ejection fraction below 50%. No symptomatic cardiac events were reported. Two patients presented asymptomatic grade I radiation pneumonitis. Acute skin toxicity was grade III (one patient), grade II (6 patients), and grade I (5 patients). There were two grade II esophagitis. Combination of pertuzumab, trastuzumab and radiotherapy was well tolerated, which should be confirmed by the results of larger studies. Copyright © 2017 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  5. Four-dimensional modelling of the mitral valve by real-time 3D transoesophageal echocardiography: proof of concept.

    Science.gov (United States)

    Noack, Thilo; Mukherjee, Chirojit; Kiefer, Philipp; Emrich, Fabian; Vollroth, Marcel; Ionasec, Razvan Ioan; Voigt, Ingmar; Houle, Helene; Ender, Joerg; Misfeld, Martin; Mohr, Friedrich Wilhelm; Seeburger, Joerg

    2015-02-01

    The complexity of the mitral valve (MV) anatomy and function is not yet fully understood. Assessing the dynamic movement and interaction of MV components to define MV physiology during the complete cardiac cycle remains a challenge. We herein describe a novel semi-automated 4D MV model. The model applies quantitative analysis of the MV over a complete cardiac cycle based on real-time 3D transoesophageal echocardiography (RT3DE) data. RT3DE data of MVs were acquired for 18 patients. The MV annulus and leaflets were semi-automatically reconstructed. Dimensions of the mitral annulus (anteroposterior and anterolateral-posteromedial diameter, annular circumference, annular area) and leaflets (MV orifice area, intercommissural distance) were acquired. Variability and reproducibility (intraclass correlation coefficient, ICC) for interobserver and intraobserver comparison were quantified at 4 time points during the cardiac cycle (mid-systole, end-systole, mid-diastole and end-diastole). Mitral annular dimensions provided highly reliable and reproducible measurements throughout the cardiac cycle for interobserver (variability range, 0.5-1.5%; ICC range, 0.895-0.987) and intraobserver (variability range, 0.5-1.6%; ICC range, 0.827-0.980) comparison, respectively. MV leaflet parameters showed a high reliability in the diastolic phase (variability range, 0.6-9.1%; ICC range, 0.750-0.986), whereas MV leaflet dimensions showed a high variability and lower correlation in the systolic phase (variability range, 0.6-22.4%; ICC range, 0.446-0.915) compared with the diastolic phase. This 4D model provides detailed morphological reconstruction as well as sophisticated quantification of the complex MV structure and dynamics throughout the cardiac cycle with a precision not yet described. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  6. Stereotactic radiotherapy for vestibular schwannoma

    DEFF Research Database (Denmark)

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno

    2014-01-01

    BACKGROUND: Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy. OBJECTIVES: To assess...... the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL......; Web of Science; CAB Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 24 July 2014. SELECTION CRITERIA: Randomised controlled trials (RCTs) exploring the efficacy of stereotactic radiotherapy compared with observation alone, microsurgical...

  7. Brady-tachycardia syndrome after radiotherapy for lung cancer. Assessment by computed tomography and carbon-11 methionine positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Takuya; Michihata, Tetsuo; Katagiri, Takashi [Showa Univ., Tokyo (Japan). School of Medicine; Okazaki, Osamu; Izumo, Kazuhide; Harumi, Kenichi

    1999-09-01

    A 74-year-old male who had received radiotherapy (total 54 Gy) for right lung cancer 7 months earlier developed a symptomatic brady-tachycardia syndrome requiring the implantation of a permanent pacemaker. Chest CT showed a pulmonary tumor of 2-cm diameter in the right lower lobe with direct extension into the surrounding tissue, suggesting the possibility of cardiac invasion. Carbon-11 methionine positron emission tomography (PET) indicated the absence of visible invasion of the heart with lung cancer. The brady-tachycardia syndrome, therefore, was considered to be associated with sinus node injury due to radiation. Carbon-11 methionine PET metabolic imaging might play an important role in evaluating noninvasively the cause of the arrhythmia in this patient. (author)

  8. Planning target volume assessment in lung tumors during 3D conformal radiotherapy by means of an aSi electronic portal imaging device in cine mode.

    Science.gov (United States)

    Caivano, R; Clemente, S; Fiorentino, A; Chiumento, C; Pedicini, P; Califano, G; Cozzolino, M; Fusco, V

    2013-08-01

    The major uncertainties in treating lung cancer are the repositioning errors and respiratory lung tumor motion. Typically, margins are added to the clinical target volume (CTV) to obtain a planning target volume (PTV) allowing the accommodation of such uncertainties. We want to test a new technique to assess the adequacy of the chosen PTV using an aSi electronic portal imaging device (EPID). Four patients affected by lung cancer and treated by radical 3D conformal radiotherapy (3DRT) were studied. During treatment the EPID was used in cine mode acquisition: acquired images were used to the aim. Treatment monitoring with an EPID in cine mode is shown to be a clinically feasible and useful tool.

  9. Radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma: Dosimetric comparison and risk assessment of solid secondary cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Sun Hyun; Park, Hee Chul; Lim, Do Hoon [Dept. of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Dong Wook [Dept. of Radiation Oncology, Kyung Hee University Hospital at Gangdong, Seoul (Korea, Republic of); Kim, Mi Sook [Dept. of Radiation Oncology, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Shin, Myung Hee [Dept. of Social and Preventive Medicine, Sungkyunkwan University School of Medicine, Suwon (Korea, Republic of)

    2017-03-15

    We compared the dosimetric parameters and the risk of solid secondary cancer from scattered doses among anterior-posterior/posterior-anterior parallel-opposed fields (AP/PA), anterior, posterior, right, and left lateral fields (4{sub f}ield), 3-dimensional conformal radiotherapy (3D-CRT) using noncoplanar beams, and intensity-modulated radiotherapy composed of 7 coplanar beams (IMRT{sub c}o) and 7 coplanar and noncoplanar beams (IMRT{sub n}on). We retrospectively generated 5 planning techniques for 5 patients with gastric MALToma. Homogeneity index (HI), conformity index (CI), and mean doses of the kidney and liver were calculated from the dose-volume histograms. Applied the Biological Effects of Ionizing Radiation VII report to scattered doses, the lifetime attributable risk (LAR) was calculated to estimate the risk of solid secondary cancer. The best value of CI was obtained with IMRT, although the HI varied among patients. The mean kidney dose was the highest with AP/PA, followed by 4{sub f}ield, 3D-CRT, IMRT{sub c}o, and IMRT{sub n}on. On the other hand, the mean liver dose was the highest with 4{sub f}ield and the lowest with AP/PA. Compared with 4{sub f}ield, the LAR for 3D-CRT decreased except the lungs, and the LAR for IMRT{sub c}o and IMRT{sub n}on increased except the lungs. However, the absolute differences were much lower than <1%. Tailored RT techniques seem to be beneficial because it could achieve adjacent organ sparing with very small and clinically irrelevant increase of secondary solid cancer risk compared to the conventional techniques.

  10. Construction of response solutions for two classes of quasi-periodically forced four-dimensional nonlinear systems with degenerate equilibrium point under small perturbations

    Science.gov (United States)

    Si, Wen; Si, Jianguo

    2017-05-01

    By developing two KAM theorems, in this paper, we show that two classes of quasi-periodically forced four-dimensional nonlinear systems with degenerate equilibrium point, a reversible system and a non-conservative system, admit a response solution under small perturbations. For the degenerate reversible system, applying special structure of unperturbed nonlinear term and Herman method, we successfully control the shift of equilibrium point, which is difficult in view of the degenerate linear term. For the degenerate non-conservative system, KAM method is brought into force even in completely degenerate case because of the restrictions on the smallness and average of perturbation. Moreover, arithmetic condition on the frequency is assumed to satisfy the Brjuno-Rüssmann's non-resonant condition. By the Pöschel-Rüssmann KAM method, we prove that these two kinds of perturbed systems can be reduced to a suitable normal form with zero as equilibrium point by a quasi-periodic transformation.

  11. Development of Four Dimensional Human Model that Enables Deformation of Skin, Organs and Blood Vessel System During Body Movement - Visualizing Movements of the Musculoskeletal System.

    Science.gov (United States)

    Suzuki, Naoki; Hattori, Asaki; Hashizume, Makoto

    2016-01-01

    We constructed a four dimensional human model that is able to visualize the structure of a whole human body, including the inner structures, in real-time to allow us to analyze human dynamic changes in the temporal, spatial and quantitative domains. To verify whether our model was generating changes according to real human body dynamics, we measured a participant's skin expansion and compared it to that of the model conducted under the same body movement. We also made a contribution to the field of orthopedics, as we were able to devise a display method that enables the observer to more easily observe the changes made in the complex skeletal muscle system during body movements, which in the past were difficult to visualize.

  12. Rotationally acquired four-dimensional optical coherence tomography of embryonic chick hearts using retrospective gating on the common central A-scan

    DEFF Research Database (Denmark)

    Happel, Christoph M.; Thommes, Jan; Thrane, Lars

    2011-01-01

    We introduce a new method of rotational image acquisition for four-dimensional (4D) optical coherence tomography (OCT) of beating embryonic chick hearts. The rotational axis and the central A-scan of the OCT are identical. An out-of-phase image sequence covering multiple heartbeats is acquired...... at every angle of an incremental rotation of the deflection mirrors of the OCT system. Image acquisition is accomplished after a rotation of 180◦. Comparison of a displayed live M-mode of the central A-scan with a reference M-mode allows instant detection of translational movements of the embryo....... For calculation of 4D data sets, we apply an imagebased retrospective gating algorithm using the phase information of the common central A-scan present in all acquired images. This leads to cylindrical three-dimensional data sets for every time step of the cardiac cycle that can be used for 4D visualization...

  13. QUALITY ASSURANCE OF 4D-CT SCAN TECHNIQUES IN MULTICENTER PHASE III TRIAL OF SURGERY VERSUS STEREOTACTIC RADIOTHERAPY (RADIOSURGERY OR SURGERY FOR OPERABLE EARLY STAGE (STAGE 1A) NON-SMALL-CELL LUNG CANCER [ROSEL] STUDY)

    NARCIS (Netherlands)

    Hurkmans, Coen W.; van Lieshout, Maarten; Schuring, Danny; van Heumen, Marielle J. T.; Cuijpers, Johan P.; Lagerwaard, Frank J.; Widder, Joachim; van der Heide, Uulke A.; Senan, Suresh

    2011-01-01

    Purpose: To determine the accuracy of four-dimensional computed tomography (4D-CT) scanning techniques in institutions participating in a Phase III trial of surgery vs. stereotactic radiotherapy (SBRT) for lung cancer. Methods and Materials: All 9 centers performed a 4D-CT scan of a motion phantom

  14. Imaging in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Calandrino, R. [Medical Physics Department, Scientific Institute H. S. Raffaele, Vita-Salute University, Milan (Italy)], E-mail: calandrino.riccardo@hsr.it; Del Maschio, A. [Radiology Department, Scientific Institute H. S. Raffaele, Vita-Salute University, Milan (Italy); Cattaneo, G.M. [Medical Physics Department, Scientific Institute H. S. Raffaele, Vita-Salute University, Milan (Italy); Castiglioni, I. [IBFM-CNR, Nuclear Medicine Department, Scientific Institute H. S. Raffaele, Milan (Italy)

    2009-09-01

    The diagnostic methodologies used for the radiotherapy planning have undergone great developments in the last 30 years. Since the 1980s, after the introduction of the CT scanner, the modality for the planning moved beyond the planar 2D assessment to approach a real and more realistic volumetric 3D definition. Consequently the dose distribution, previously obtained by means of an overly simple approximation, became increasingly complex, better tailoring the true shape of the tumour. The final therapeutic improvement has been obtained by a parallel increase in the complexity of the irradiating units: the Linacs for therapy have, in fact, been equipped with a full accessory set capable to modulate the fluence (IMRT) and to check the correct target position continuously during the therapy session (IMRT-IGRT). The multimodal diagnostic approach, which integrates diagnostic information, from images of the patient taken with CT, NMR, PET and US, further improves the data for a biological and topological optimization of the radiotherapy plan and consequently of the dose distribution in the Planning Target Volume. Proteomic and genomic analysis will be the next step in tumour diagnosis. These methods will provide the planners with further information, for a true personalization of the treatment regimen and the assessment of the predictive essays for each tumour and each patient.

  15. Magnetic Resonance Compatibility of a Transponder Aimed for Radiotherapy Positioning - A Phantom Study.

    Science.gov (United States)

    Wikstrom, Johan; Isacsson, Ulf; Johansson, Bengt; Lennernäs, B O

    2017-09-01

    Electromagnetic Positioning Systems (EMP) is a new position-ing technique in four-dimensional radiotherapy. Patients with implanted transponders may be referred for magnetic resonance imaging (MRI) making it important to establish the MR safety. Oranges were prepared with transponders and imaged on a 3T MR scanner with different sequences. Computed tomography (CT) was performed as comparison. MR artifacts were assessed. An estimation of the maximum transponder de-flection force and heating was made. The mean measured displacement of transponders was 0.1 mm (range=0.03-0.3 mm). Artifacts were observed adjacent to transponders using all sequences. The deflection force on the transponder in the gantry was less than 38 mN. No heating was observed. The absence of any substantial movement, the weak measured deflection force and absence of observed heating speaks for the safe use of MR imaging with transponder 3T. Local artefacts makes evaluation impossible adjacent to transponders. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  16. Four-Dimensional Golden Search

    Energy Technology Data Exchange (ETDEWEB)

    Fenimore, Edward E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-25

    The Golden search technique is a method to search a multiple-dimension space to find the minimum. It basically subdivides the possible ranges of parameters until it brackets, to within an arbitrarily small distance, the minimum. It has the advantages that (1) the function to be minimized can be non-linear, (2) it does not require derivatives of the function, (3) the convergence criterion does not depend on the magnitude of the function. Thus, if the function is a goodness of fit parameter such as chi-square, the convergence does not depend on the noise being correctly estimated or the function correctly following the chi-square statistic. And, (4) the convergence criterion does not depend on the shape of the function. Thus, long shallow surfaces can be searched without the problem of premature convergence. As with many methods, the Golden search technique can be confused by surfaces with multiple minima.

  17. Bystander effects and radiotherapy.

    Science.gov (United States)

    Marín, Alicia; Martín, Margarita; Liñán, Olga; Alvarenga, Felipe; López, Mario; Fernández, Laura; Büchser, David; Cerezo, Laura

    2015-01-01

    Radiation-induced bystander effects are defined as biological effects expressed after irradiation by cells whose nuclei have not been directly irradiated. These effects include DNA damage, chromosomal instability, mutation, and apoptosis. There is considerable evidence that ionizing radiation affects cells located near the site of irradiation, which respond individually and collectively as part of a large interconnected web. These bystander signals can alter the dynamic equilibrium between proliferation, apoptosis, quiescence or differentiation. The aim of this review is to examine the most important biological effects of this phenomenon with regard to areas of major interest in radiotherapy. Such aspects include radiation-induced bystander effects during the cell cycle under hypoxic conditions when administering fractionated modalities or combined radio-chemotherapy. Other relevant aspects include individual variation and genetics in toxicity of bystander factors and normal tissue collateral damage. In advanced radiotherapy techniques, such as intensity-modulated radiation therapy (IMRT), the high degree of dose conformity to the target volume reduces the dose and, therefore, the risk of complications, to normal tissues. However, significant doses can accumulate out-of-field due to photon scattering and this may impact cellular response in these regions. Protons may offer a solution to reduce out-of-field doses. The bystander effect has numerous associated phenomena, including adaptive response, genomic instability, and abscopal effects. Also, the bystander effect can influence radiation protection and oxidative stress. It is essential that we understand the mechanisms underlying the bystander effect in order to more accurately assess radiation risk and to evaluate protocols for cancer radiotherapy.

  18. Qualitative interpretation of PET scans using a Likert scale to assess neck node response to radiotherapy in head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Sjoevall, Johanna; Wahlberg, Peter [Lund University, Department of Otorhinolaryngology (ORL)-Head and Neck Surgery, Skane University Hospital, Lund (Sweden); Bitzen, Ulrika [Lund University, Department of Clinical Physiology and Nuclear Medicine, Skane University Hospital, Lund (Sweden); Kjellen, Elisabeth; Nilsson, Per; Brun, Eva [Lund University, Department of Oncology and Radiation Physics, Skane University Hospital, Lund (Sweden)

    2016-04-15

    The aim of this study was to determine whether PET scans after radiotherapy (RT), visually interpreted as equivocal regarding metabolic neck node response can be used to accurately categorize patients as responders or nonresponders using a Likert scale and/or maximum standardized uptake value (SUVmax). Other aims were to determine the performance of different methods for assessing post-RT PET scans (visual inspection, a Likert scale and SUVmax) and to establish whether any method is superior in predicting regional control (RC) and overall survival (OS). In 105 patients with neck node-positive head and neck cancer, the neck node response was evaluated by FDG PET/CT 6 weeks after RT. The scans were clinically assessed by visual inspection and, for the purposes of this analysis, re-evaluated using the Deauville criteria, a five-point Likert scale previously used in lymphoma studies. In addition, SUVmax was determined. All assessment methods were able to significantly predict RC but not OS. The methods were also able to significantly predict remission of tumour after completion of RT. Of the 105 PET scans, 19 were judged as equivocal on visual inspection. The Likert scale was preferable to SUVmax for grouping patients as responders or nonresponders. All methods (visual inspection, SUVmax and the Likert scale) identified responders and nonresponders and predicted RC. A Likert scale is a promising tool to reduce to a minimum the problem of PET scans judged as equivocal. Consensus regarding qualitative assessment would facilitate PET reporting in clinical practice. (orig.)

  19. Assessing feasibility, compliance and toxicity of concomitant chemo-radiotherapy in head and neck cancers in the Northern Territory: initial experience and challenges.

    Science.gov (United States)

    Gupta, Ajay; Baxi, Siddhartha; Hoyne, Christopher

    2017-06-01

    Comprehensive oncology services have recently been introduced in the Northern Territory (NT) enabling delivery of concurrent chemo-radiotherapy (CCRT) in locally advanced head and neck squamous cell carcinoma (LAHNSC). The purpose of this study is to assess feasibility, compliance and toxicity of CCRT in remote Australia. Chart review was conducted for all patients >18 years, with biopsy-proven LAHNSC, receiving curative intent CCRT between January 2010 and September 2012. The study population comprised of 26 patients, 20 Caucasian and 6 Indigenous, having a median age of 58 years, with most common sites of involvement being the oropharynx (n = 16) and the oral cavity (n = 6). Major risk factors were smoking and alcoholism. Cardiovascular disease, viral hepatitis, latent tuberculosis and strongyloidosis were the major comorbidities. Fifty-eight per cent (n = 15) required assisted feeding. All patients received intensity modulated radiotherapy. Systemic therapy comprised of cisplatin or carboplatin/cetuximab. Most common acute (grade 3/4) toxicities were mucositis, dysphagia and dermatological in 54%, 31% and 23% respectively. Complications were infection and gastrostomy insertion related. Hospitalisation occurred in 23%, treatment break >2 days in 38%, with no difference in toxicities between indigenous and nonindigenous patients. Platinum use was associated with greater nausea (P = 0.003), renal dysfunction (P = 0.03) and ototoxicity (P = 0.04) and cetuximab with dermatological reactions (P = 0.05). At median follow-up of 16 months, overall survival was 58% with progression-free survival of 50%. We have demonstrated good compliance rates, tolerance and feasibility outcomes. The seeming preponderance of LAHNSC in the NT is cause for concern. © 2016 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation

  20. Radiotherapy for Hodgkin lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena [Rigshospitalet Copenhagen Univ. (Denmark). Depts. of Oncology and Haematology; Yahalom, Joachim (eds.) [Memorial Sloan-Kettering Cancer, New York, NY (United States). Dept. of Radiation Oncology

    2011-07-01

    This book deals in detail with all aspects of the best practice in modern radiotherapy for Hodgkin lymphoma. It provides the background and rationale for the inclusion of radiotherapy in today's combined-modality approach, including special clinical situations such as Hodgkin lymphoma in children, in the pregnant patient, and in the elderly. Radiotherapy planning using state-of-the-art imaging, target definition, planning software, and treatment equipment is expounded in detail. Acute and long-term side effects of radiotherapy are analyzed, and the implications for modern radiotherapy approaches in Hodgkin lymphomas are explained. (orig.)

  1. Radiotherapy for benign disease; assessing the risk of radiation-induced cancer following exposure to intermediate dose radiation

    Science.gov (United States)

    Hatfield, Paul; Prestwich, Robin JD; Shaffer, Richard E; Taylor, Roger E

    2015-01-01

    Most radiotherapy (RT) involves the use of high doses (>50 Gy) to treat malignant disease. However, low to intermediate doses (approximately 3–50 Gy) can provide effective control of a number of benign conditions, ranging from inflammatory/proliferative disorders (e.g. Dupuytren's disease, heterotopic ossification, keloid scarring, pigmented villonodular synovitis) to benign tumours (e.g. glomus tumours or juvenile nasopharyngeal angiofibromas). Current use in UK RT departments is very variable. This review identifies those benign diseases for which RT provides good control of symptoms with, for the most part, minimal side effects. However, exposure to radiation has the potential to cause a radiation-induced cancer (RIC) many years after treatment. The evidence for the magnitude of this risk comes from many disparate sources and is constrained by the small number of long-term studies in relevant clinical cohorts. This review considers the types of evidence available, i.e. theoretical models, phantom studies, epidemiological studies, long-term follow-up of cancer patients and those treated for benign disease, although many of the latter data pertain to treatments that are no longer used. Informative studies are summarized and considered in relation to the potential for development of a RIC in a range of key tissues (skin, brain etc.). Overall, the evidence suggests that the risks of cancer following RT for benign disease for currently advised protocols are small, especially in older patients. However, the balance of risk vs benefit needs to be considered in younger adults and especially if RT is being considered in adolescents or children. PMID:26462717

  2. Chromosome elasticity and mitotic polar ejection force measured in living Drosophila embryos by four-dimensional microscopy-based motion analysis.

    Science.gov (United States)

    Marshall, W F; Marko, J F; Agard, D A; Sedat, J W

    2001-04-17

    Mitosis involves the interaction of many different components, including chromatin, microtubules, and motor proteins. Dissecting the mechanics of mitosis requires methods of studying not just each component in isolation, but also the entire ensemble of components in its full complexity in genetically tractable model organisms. We have developed a mathematical framework for analyzing motion in four-dimensional microscopy data sets that allows us to measure elasticity, viscosity, and forces by tracking the conformational movements of mitotic chromosomes. We have used this approach to measure, for the first time, the basic biophysical parameters of mitosis in wild-type Drosophila melanogaster embryos. We found that Drosophila embryo chromosomes are significantly less rigid than the much larger chromosomes of vertebrates. Anaphase kinetochore force and nucleoplasmic viscosity were comparable with previous estimates in other species. Motion analysis also allowed us to measure the magnitude of the polar ejection force exerted on chromosome arms during metaphase by individual microtubules. We find the magnitude of this force to be approximately 1 pN, a number consistent with force generation either by collision of growing microtubules with chromosomes or by single kinesin motors. Motion analysis allows noninvasive mechanical measurements to be made in complex systems. This approach should allow the functional effects of Drosophila mitotic mutants on chromosome condensation, kinetochore forces, and the polar ejection force to be determined.

  3. Dimensional Reduction of N=1, E_8 SYM over SU(3)/U(1) x U(1) x Z_3 and its four-dimensional effective action

    CERN Document Server

    Irges, Nikos; Zoupanos, George

    2011-01-01

    We present an extension of the Standard Model inspired by the E_8 x E_8 Heterotic String. In order that a reasonable effective Lagrangian is presented we neglect everything else other than the ten-dimensional N=1 supersymmetric Yang-Mills sector associated with one of the gauge factors and certain couplings necessary for anomaly cancellation. We consider a compactified space-time M_4 x B_0 / Z_3, where B_0 is the nearly-Kaehler manifold SU(3)/U(1) x U(1) and Z_3 is a freely acting discrete group on B_0. Then we reduce dimensionally the E_8 on this manifold and we employ the Wilson flux mechanism leading in four dimensions to an SU(3)^3 gauge theory with the spectrum of a N=1 supersymmetric theory. We compute the effective four-dimensional Lagrangian and demonstrate that an extension of the Standard Model is obtained with interesting features including a conserved baryon number and fixed tree level Yukawa couplings and scalar potential. The spectrum contains new states such as right handed neutrinos and heavy ...

  4. Four-dimensional real-time cine images of wrist joint kinematics using dual source CT with minimal time increment scanning.

    Science.gov (United States)

    Choi, Yoon Seong; Lee, Young Han; Kim, Sungjun; Cho, Hee Woo; Song, Ho-Taek; Suh, Jin-Suck

    2013-07-01

    To validate the feasibility of real time kinematography with four-dimensional (4D) dynamic functional wrist joint imaging using dual source CT. Two healthy volunteers performed radioulnar deviation and pronation- supination wrist motions for 10 s and 4 s per cycle in a dual source CT scanner. Scan and reconstruction protocols were set to optimize temporal resolution. Cine images of the reconstructed carpal bone of the moving wrist were recorded. The quality of the images and radiation dosage were evaluated. The 4D cine images obtained during 4 s and 10 s of radioulnar motion showed a smooth stream of movement with good quality and little noise or artifact. Images from the pronation-supination motion showed noise with a masked surface contour. The temporal resolution was optimized at 0.28 s. Using dual source CT, 4D cine images of in vivo kinematics of wrist joint movement were obtained and found to have a shorter scan time, improved temporal resolution and lower radiation dosages compared with those previously reported.

  5. Evaluating the cross-cultural validity of the Polish version of the Four-Dimensional Symptom Questionnaire (4DSQ) using differential item functioning (DIF) analysis.

    Science.gov (United States)

    Czachowski, Sławomir; Terluin, Berend; Izdebski, Adam; Izdebski, Paweł

    2012-10-01

    The original Dutch Four-Dimensional Symptom Questionnaire (4DSQ), which measures distress, depression, anxiety and somatization, has been translated into Polish with the aim of providing primary health care with a good screening instrument for the detection of the most prevalent mental health problems (anxiety, somatization, depression and distress). To check if the Polish version is cross-culturally valid so that the scores of Polish subjects can be compared with the scores of Dutch subjects and the Dutch cut-off points can be used in Polish subjects. 4DSQ data were collected from a mixed sample of students and primary care attendees. The Polish data were compared with the 4DSQ data of a matched sample of Dutch students and primary care attendees. Two methods of differential item functioning (DIF) analysis, ordinal logistic regression and generalized Mantel-Haenszel, were used to detect items with DIF, and linear regression analysis was used to estimate the scale-level impact of DIF. Four items showing DIF were detected in the distress scale, one in the somatization scale and one in the anxiety scale. The DIF in distress caused Polish subjects with moderate scores to score circa 1 point less than their Dutch counterparts. The results of the DIF analyses suggest that the Polish 4DSQ measures the same constructs as the Dutch 4DSQ and that the Dutch norms can be used for the Polish subjects, except for distress: the first cut-off point should be one point lower.

  6. Four-Dimensional Thermal Analysis of 888 nm Pumped Nd:YVO4 Dual-Rod Acousto-Optic Q-Switched Laser

    Directory of Open Access Journals (Sweden)

    Yijie Shen

    2017-05-01

    Full Text Available A theoretical analysis upon the four-dimensional (4D spatio-temporal temperature dependent dynamics of 888 nm pumped Nd:YVO 4 dual-rod laser is established, which is valid in both continuous-wave (CW and acousto-optic (AO Q-switched pulse lasers conditions. Our model can accurately solve the 4D thermal generation and temperature evolution not only in the steady Q-switched state, but also in the first few unstable giant or dwarf pulses region. Factors including ground state depletion (GSD, energy transfer upconversion (ETU, fluorescence branching ratios, temperature-dependent cross sections and nonradiative relaxations processes are comprehensively considered for precisely estimating thermal effects, valid in both the steady pulse region and the unstable region at the beginning. Moreover, temporal and spatial temperature profiles and their coupling effect on output properties at different repetition-rates are discussed. Experiments of high-power high-repetition-rate 888 nm end-pumped Nd:YVO 4 dual-rod CW and AO Q-switched lasers are also firstly presented and the experimental results enjoy good consistency with our theory.

  7. Real-Space Imaging of Carrier Dynamics of Materials Surfaces by Second-Generation Four-Dimensional Scanning Ultrafast Electron Microscopy

    KAUST Repository

    Sun, Jingya

    2015-09-14

    In the fields of photocatalysis and photovoltaics, ultrafast dynamical processes, including carrier trapping and recombination on material surfaces, are among the key factors that determine the overall energy conversion efficiency. A precise knowledge of these dynamical events on the nanometer (nm) and femtosecond (fs) scales was not accessible until recently. The only way to access such fundamental processes fully is to map the surface dynamics selectively in real space and time. In this study, we establish a second generation of four-dimensional scanning ultrafast electron microscopy (4D S-UEM) and demonstrate the ability to record time-resolved images (snapshots) of material surfaces with 650 fs and ∼5 nm temporal and spatial resolutions, respectively. In this method, the surface of a specimen is excited by a clocking optical pulse and imaged using a pulsed primary electron beam as a probe pulse, generating secondary electrons (SEs), which are emitted from the surface of the specimen in a manner that is sensitive to the local electron/hole density. This method provides direct and controllable information regarding surface dynamics. We clearly demonstrate how the surface morphology, grains, defects, and nanostructured features can significantly impact the overall dynamical processes on the surface of photoactive-materials. In addition, the ability to access two regimes of dynamical probing in a single experiment and the energy loss of SEs in semiconductor-nanoscale materials will also be discussed.

  8. Phase I Clinical Trial Assessing Temozolomide and Tamoxifen With Concomitant Radiotherapy for Treatment of High-Grade Glioma

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Shilpen, E-mail: Shilpenp@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, WA (United States); DiBiase, Steven [Robert Wood Johnson School of Medicine, Camden, NJ (United States); Meisenberg, Barry [DeCesaris Cancer Institute, Annapolis, MD (United States); Flannery, Todd [Princeton Radiation Oncology, Princeton, NJ (United States); Patel, Ashish [Division of Radiation Oncology, Abington Memorial Hospital, Abington, PA (United States); Dhople, Anil [MIMA Cancer Center, Melbourne, FL (Australia); Cheston, Sally; Amin, Pradip [Department of Radiation Oncology, University of Maryland, Baltimore, MD (United States)

    2012-02-01

    Purpose: The new standard treatment of glioblastoma multiforme is concurrent radiotherapy (RT) and temozolomide. The proliferation of high-grade gliomas might be partly dependent on protein kinase C-mediated pathways. Tamoxifen has been shown in vitro to inhibit protein kinase C through estrogen receptor-independent antineoplastic effects. This Phase I trial was designed to determine the maximal tolerated dose (MTD) of tamoxifen when given with temozolomide and concurrent RT to patients with high-grade gliomas. Methods and Materials: A total of 17 consecutive patients in four cohorts with World Health Organization Grade 3 (n = 2) and 4 (n = 15) gliomas were given tamoxifen twice daily during 6 weeks of concurrent RT and temozolomide. Eligibility included histologic diagnosis, age >18 years old, Karnofsky performance status {>=}60, and no previous brain RT or chemotherapy. The starting dose was 50 mg/m{sup 2} divided twice daily. If no dose-limiting toxicities (DLTs) occurred in 3 patients, the dose was escalated in 25-mg/m{sup 2} increments until the MTD was reached. When {>=}2 patients within a cohort experienced a DLT, the MTD had been exceeded. Temozolomide was given with RT at 75 mg/m{sup 2}. A dose of 60 Gy in 2 Gy/d fractions to a partial brain field was delivered. Results: A total of 6 patients in Cohort 4 had received tamoxifen at 125 mg/m{sup 2}. One patient was excluded, and the fourth patient developed Grade 4 thrombocytopenia (DLT). Thus, 3 more patients needed to be enrolled. A deep venous thrombosis (DLT) occurred in the sixth patient. Thus, the MTD was 100 mg/m{sup 2}. Conclusions: The MTD of tamoxifen was 100 mg/m{sup 2} when given concurrently with temozolomide 75 mg/m{sup 2} and RT. Tamoxifen might have a role in the initial treatment of high-grade gliomas and should be studied in future Phase II trials building on the newly established platform of concurrent chemoradiotherapy.

  9. Client perception of radiotherapy services at the Lagos University ...

    African Journals Online (AJOL)

    Assessment of quality from the patient's perspective could be a method of aiding improvement of services to achieve total quality management. This study set out to determine the level of knowledge of radiotherapy among patients and assess their attitude to the radiotherapy services provided at the Oncology clinic of the ...

  10. [Radiotherapy of bone metastases].

    Science.gov (United States)

    Thureau, S; Vieillard, M-H; Supiot, S; Lagrange, J-L

    2016-09-01

    Radiotherapy plays a major role in palliative treatment of bone metastases. Recent developments of stereotactic radiotherapy and intensity modulated radiation therapy give the possibility to treat oligometastatic diseases. The objective of this paper is to report indications and treatment modalities of radiotherapy in these situations. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  11. Assessment of Viscous Energy Loss and the Association with Three-Dimensional Vortex Ring Formation in Left Ventricular Inflow : In Vivo Evaluation Using Four-Dimensional Flow MRI

    NARCIS (Netherlands)

    Elbaz, MSM; van der Geest, R; Calkoen, EE; de Roos, A.; Lelieveldt, B.P.F.; Roest, AAW; Westenberg, JJM

    2017-01-01

    Purpose To evaluate viscous energy loss and the association with three-dimensional (3D) vortex ring formation in left ventricular (LV) blood flow during diastolic filling. Theory and Methods Thirty healthy volunteers were compared with 32 patients with corrected atrioventricular septal defect as

  12. Assessment of viscous energy loss and the association with three-dimensional vortex ring formation in left ventricular inflow: In vivo evaluation using four-dimensional flow MRI.

    Science.gov (United States)

    Elbaz, Mohammed S M; van der Geest, Rob J; Calkoen, Emmeline E; de Roos, Albert; Lelieveldt, Boudewijn P F; Roest, Arno A W; Westenberg, Jos J M

    2017-02-01

    To evaluate viscous energy loss and the association with three-dimensional (3D) vortex ring formation in left ventricular (LV) blood flow during diastolic filling. Thirty healthy volunteers were compared with 32 patients with corrected atrioventricular septal defect as unnatural mitral valve morphology and inflow are common in these patients. 4DFlow MRI was acquired from which 3D vortex ring formation was identified in LV blood flow at peak early (E)-filling and late (A)-filling and characterized by its presence/absence, orientation, and position from the lateral wall. Viscous energy loss was computed over E-filling, A-filling, and complete diastole using the Navier-Stokes energy equations. Compared with healthy volunteers, viscous energy loss was significantly elevated in patients with disturbed vortex ring formation as characterized by a significantly inclined orientation and/or position closer to the lateral wall. Highest viscous energy loss was found in patients without a ring-shaped vortex during E-filling (on average more than double compared with patients with ring-shape vortex, P formation was associated with significant increase in total viscous energy loss over diastole even in the presence of normal E-filling vortex ring. Altered vortex ring formation during LV filling is associated with increased viscous energy loss. Magn Reson Med 77:794-805, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

  13. Radiotherapy in small countries.

    Science.gov (United States)

    Barton, Michael B; Zubizarreta, Eduardo H; Polo Rubio, J Alfredo

    2017-10-01

    To examine the availability of radiotherapy in small countries. A small country was defined as a country with a population less than one million persons. The economic status of each country was defined using the World Bank Classification. The number of cancers in each country was obtained from GLOBOCAN 2012. The number of cancer cases with an indication or radiotherapy was calculated using the CCORE model. There were 41 countries with a population of under 1 million; 15 were classified as High Income, 15 Upper Middle Income, 10 Lower Middle Income and one Low Income. 28 countries were islands. Populations ranged from 799 (Holy See) to 886450 (Fiji) and the total number of cancer cases occurring in small countries was 21,043 (range by country from 4 to 2476). Overall the total number of radiotherapy cases in small countries was 10982 (range by country from 2 to 1239). Radiotherapy was available in all HIC islands with 80 or more new cases of cancer in 2012 but was not available in any LMIC island. Fiji was the only LMIC island with a large radiotherapy caseload. Similar caseloads in non-island LMIC all had radiotherapy services. Most non-island HIC did not have radiotherapy services presumably because of the easy access to radiotherapy in neighbouring countries. There are no radiotherapy services in any LMIC islands. Copyright © 2017. Published by Elsevier Ltd.

  14. Assessing the impact of an alternative biochemical failure definition on radiation dose response for high-risk prostate cancer treated with external beam radiotherapy.

    Science.gov (United States)

    Cheung, Rex; Tucker, Susan L; Lee, Andrew L; Dong, Lei; Kamat, Ashish; Pisters, Louis; Kuban, Deborah A

    2005-01-01

    The American Society for Therapeutic Radiology and Oncology (ASTRO) biochemical failure definition has recently been compared with various alternative definitions. We assessed the effect of using an alternative failure definition on the dose-response characteristics of high-risk prostate cancer treated with radiotherapy alone. This study included 363 high-risk prostate cancer patients treated with external beam radiotherapy alone from 1987 to 1999. These patients have one or more of the following: 1992 American Joint Committee on Cancer (AJCC) digital rectal examination (DRE) stage > or = cT3, prostate-specific antigen (PSA) > 20 ng/mL, and/or biopsy Gleason score > or = 8. We previously reported the dose response based on the ASTRO definition for these patients. In this study, a biochemical failure is defined as a PSA rise > or = 2 ng/mL above the current nadir PSA (CN + 2). The failure date is defined as the time at which the event occurred (i.e., the call date). Using CN + 2, the tumor control probability (TCP) continues to decrease with time as opposed to reaching a plateau as with the ASTRO definition. At 5 years, TCD50 (95% CI), the dose to achieve 50% tumor control, for high-risk prostate cancer, is 70.4 (68.0-72.9) Gy using CN + 2 [ASTRO: 75.5 (70.7-80.2) Gy]. The relative slope, gamma50 (95% CI) is 1.8 (0.8-2.8) [ASTRO: 1.7 (0.7-2.7)]. Recursive partitioning again identified two subgroups: PSA or = 13 ng/mL (ASTRO: PSA 20 ng/mL). The difference in TCD50 between the two subgroups is about 20 Gy at 5 years (ASTRO: about 15 Gy at 5 years). This analysis using the CN + 2 failure definition continues to show a dose response for the high-risk group of patients. However, the dose-response characteristics differ from those estimated using the ASTRO definition. We observed that the position (TCD50) and steepness (gamma50) of the dose-response curve changed with time as long as the TCP continued to decrease. This suggests that the dose response characteristics

  15. Intrathoracic extensive-stage small cell lung cancer: assessment of the benefit of thoracic and brain radiotherapy using the SEER database.

    Science.gov (United States)

    Mahmoud, Omar; Kwon, Deukwoo; Greenfield, Brad; Wright, Jean L; Samuels, Michael A

    2016-12-01

    Extensive-stage small cell lung cancer (ESCLC) includes metastatic disease and locally advanced disease confined to the thorax that cannot be encompassed in a typical radiation portal. We assessed and then compared the benefits of thoracic radiotherapy (TRT) and/or brain radiotherapy (BRT) on overall survival (OS) between the intrathoracic (T-ESCLC) and metastatic (M-ESCLC) groups using the Surveillance Epidemiology and End Results database. TRT and BRT data were available for 10150 patients treated from 1988-1997. The T-ESCLC group included 1774 patients. The Kaplan-Meier method was used to estimate OS and the proportional hazards model was used to estimate OS hazard ratios for prognostic factors including age, gender, race, tumor size, T/N stage, TRT, and BRT. The 2-year OS for T-ESCLC was 7.8 % compared to 3 % in the M-ESCLC group (p < 0.001). In the T-ESCLC group, TRT and BRT were delivered to 750 and 102 patients, respectively. The 2-year OS was 13 % in the TRT group compared to 4.1 % in the no-TRT group (p ≤ 0.001) and 22.5 % in the BRT group compared to 7 % in the no-BRT group (p < 0.001). In the M-ESCLC group, TRT and BRT were delivered to 3093 and 1887 patients, respectively. The 2-year OS was 4.4 % in the TRT group compared to 2.8 % in the no-TRT group (p < 0.001) and 4.3 % in the BRT compared to 2.6 % in the no-BRT group (p < 0.001). Age, gender, TRT and BRT were significant OS prognostic factors in both groups. Our study suggests that T-ESCLC is a disease entity distinct from M-ESCLC. Prospective studies to determine whether TRT should be recommended for the thoracic-only subgroup are warranted.

  16. Self-assessed bowel toxicity after external beam radiotherapy for prostate cancer - predictive factors on irritative symptoms, incontinence and rectal bleeding

    Directory of Open Access Journals (Sweden)

    Klotz Jens

    2009-09-01

    Full Text Available Abstract Background The aim of the study was to evaluate self-assessed bowel toxicity after radiotherapy (RT for prostate cancer. In contrast to rectal bleeding, information concerning irritative symptoms (rectal urgency, pain and incontinence after RT has not been adequately documented and reported in the past. Methods Patients (n = 286 have been surveyed prospectively before (A, at the last day (70.2-72.0 Gy; B, a median time of two (C and 16 months after RT (D using a validated questionnaire (Expanded Prostate Cancer Index Composite. Bowel domain score changes were analyzed and patient-/dose-volume-related factors tested for a predictive value on three separate factors (subscales: irritative symptoms, incontinence and rectal bleeding. Results Irritative symptoms were most strongly affected in the acute phase, but the scores of all subscales remained slightly lower at time D in comparison to baseline scores. Good correlations (correlation indices >0.4; p Conclusion PTV and specific comorbidities are important predictive factors on adverse bowel quality of life changes after RT for prostate cancer. However, greater rectum volumes inside high isodose levels have not been found to be associated with lower quality of life scores.

  17. Cardiovascular complications following thoracic radiotherapy in patients with cancer

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Melgaard; Borchsenius, Julie I Helene; Offersen, Birgitte Vrou

    2016-01-01

    Cardiovascular complications following thoracic radiotherapy in patients with cancer are well described. Advancements in surgery, radiotherapy and systemic treatments have led to an increasing number of cancer survivors and thus an increasing number of patients with long-term side effects...... of their cancer treatments. This article describes the short- and long-term cardiovascular morbidity and mortality following thoracic radiotherapy and further, optimal cardiovascular assessments and diagnostic tools in asymptomatic and symptomatic patients....

  18. Updates on clinical studies of selenium supplementation in radiotherapy

    OpenAIRE

    Puspitasari, Irma M.; Abdulah, Rizky; Yamazaki, Chiho; KAMEO, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2014-01-01

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation i...

  19. Correlations of third-trimester hiatal biometry obtained using four-dimensional translabial ultrasonography with the delivery route in nulliparous pregnant women

    Directory of Open Access Journals (Sweden)

    Teerayut Temtanakitpaisan

    2016-01-01

    Full Text Available Purpose: The goal of this study was to evaluate normal hiatal dimensions in the third trimester in nulliparous Thai pregnant women and to establish which biometric factors were associated with various pregnancy outcomes. Methods: Fifty-seven consecutive nulliparous pregnant Thai women in their third trimester were recruited on a voluntary basis from April to October 2014. All subjects underwent four-dimensional (4D translabial ultrasonography. Hiatal biometric parameters were measured at rest, while performing a Valsalva maneuver, and during contraction. Information about the patients’ eventual deliveries was obtained from their medical records. Results: The mean values of the patients’ age, body mass index, and gestational age at the time of examination were 27.4±5.47 years, 26.7±3.48 kg/m2, and 36.6±1.49 weeks, respectively. No subjects had vaginal lumps or experienced prolapse greater than stage 1 of the Pelvic Organ Prolapse Quantification system. Ultrasonography showed that the mean values of the hiatal area at rest, while performing a Valsalva maneuver, and during contraction were 13.10±2.92 cm2, 17.50±4.81 cm2, and 9.69±2.09 cm2, respectively. The hiatal area at rest, the axial measurement at rest, and the axial measurement while performing a Valsalva maneuver were significantly associated with the route of delivery (P=0.02, P=0.04, and P=0.03, respectively. Conclusion: The route of delivery was associated with hiatal biometric values measured using 4D translabial ultrasonography, based on the results of nulliparous Thai women in the third trimester.

  20. Optimization of acquisition parameters and accuracy of target motion trajectory for four-dimensional cone-beam computed tomography with a dynamic thorax phantom.

    Science.gov (United States)

    Shimohigashi, Yoshinobu; Araki, Fujio; Maruyama, Masato; Nakaguchi, Yuji; Nakato, Kengo; Nagasue, Nozomu; Kai, Yudai

    2015-01-01

    Our purpose in this study was to evaluate the performance of four-dimensional computed tomography (4D-CBCT) and to optimize the acquisition parameters. We evaluated the relationship between the acquisition parameters of 4D-CBCT and the accuracy of the target motion trajectory using a dynamic thorax phantom. The target motion was created three dimensionally using target sizes of 2 and 3 cm, respiratory cycles of 4 and 8 s, and amplitudes of 1 and 2 cm. The 4D-CBCT data were acquired under two detector configurations: "small mode" and "medium mode". The projection data acquired with scan times ranging from 1 to 4 min were sorted into 2, 5, 10, and 15 phase bins. The accuracy of the measured target motion trajectories was evaluated by means of the root mean square error (RMSE) from the setup values. For the respiratory cycle of 4 s, the measured trajectories were within 2 mm of the setup values for all acquisition times and target sizes. Similarly, the errors for the respiratory cycle of 8 s were <4 mm. When we used 10 or more phase bins, the measured trajectory errors were within 2 mm of the setup values. The trajectory errors for the two detector configurations showed similar trends. The acquisition times for achieving an RMSE of 1 mm for target sizes of 2 and 3 cm were 2 and 1 min, respectively, for respiratory cycles of 4 s. The results obtained in this study enable optimization of the acquisition parameters for target size, respiratory cycle, and desired measurement accuracy.

  1. Three- and Four-Dimensional Spheroid and FiSS Tumoroid Cultures: Platforms for Drug Discovery and Development and Translational Research.

    Science.gov (United States)

    Nair, R R; Padhee, S; Das, T; Green, R; Howell, M; Mohapatra, S S; Mohapatra, Subhra

    2017-01-01

    There have been remarkable improvements in our understanding of cancer biology. However, therapeutic improvements, with a few exceptions, have been minimal. Also, significant challenges remain in translating fundamental discoveries in cancer biology and genetics into effective drugs and cures. Traditional two-dimensional monolayer cell cultures lack predictive value, resulting in a >90% failure rate of compounds in clinical trials. A developing cancer is a symbiotic tissue consisting of cancer cells, including cancer stem cells (CSCs), and cohabitating with the components of its environment to form a tumor microenvironment (TME) niche. Throughout the process of tumorigenesis, ubiquitous autocrine and paracrine signaling between the cellular and noncellular components of the TME dictates the milieu and structure of this niche. Arising out of such interactions are the cancer cell's phenotypic characteristics, such as stemness, epithelial mesenchymal transformation (EMT), and drug resistance which in turn greatly affect the response of these cells to drug therapy. For these reasons, in order to delineate the mechanism of tumorigenesis and in the process discover drugs that will have greatest impact on tumor growth, it becomes imperative to study the cancer cell in context of its microenvironment. In the present review, we enumerate the advantages of three- and four-dimensional (3D and 4D) cell cultures and describe the various cell culture platforms that are being used to study tumorigenesis in vitro. These culture systems will not only aid in the study of tumor progression complexities in a cost-effective and rapid manner; they also are expected to facilitate the discovery and delivery of therapeutic regimens that will have more success making it to the clinic.

  2. Four-dimensional Transcatheter Intra-arterial Perfusion MR Imaging Before and After Uterine Artery Embolization in the Rabbit VX2 Tumor Model

    Science.gov (United States)

    Chung, Johnathan C.; Wang, Dingxin; Lewandowski, Robert J.; Tang, Richard; Chrisman, Howard B.; Vogelzang, Robert L.; Woloschak, Gayle E.; Larson, Andrew C.; Omary, Reed A.; Ryu, Robert K.

    2010-01-01

    Purpose To test the hypothesis that four-dimensional (4D) transcatheter intra-arterial perfusion (TRIP) MR imaging can measure uterine fibroid perfusion changes immediately before and after uterine artery embolization (UAE) in the rabbit VX2 tumor model. Materials and Methods Eight VX2 uterine tumors were grown in 6 rabbits. After positioning a catheter within the uterine artery, we performed 4D TRIP-MRI measurements with 3 mL injections of 2.5% gadopentetate dimeglumine. We used a dynamic 3D spoiled-GRE sequence with in vivo B1-field correction for improved accuracy during perfusion quantification. We performed UAE using 1 mL of gelatin microspheres (2×106 particles; diameter 40-120 μm). Two regions-of-interest were drawn within each tumor upon perfusion maps. Functional embolic endpoints were reported as the mean percent reduction in fibroid tumor perfusion. Measurements before and after UAE were compared using paired t-tests (α = 0.05). Results VX2 uterine tumor perfusion decreased significantly from 27.1 at baseline to 7.09 after UAE (mL/min/100 mL tissue, p < 0.0001). Overall perfusion reduction was 76.3% (95% CI: 66.3%-86.3%). Conclusion 4D TRIP MRI can objectively quantify uterine fibroid perfusion reductions during UAE in VX2 rabbits. This technique could be used clinically to potentially determine an optimal embolic endpoint with the long-term goals of improving UAE success rates and minimizing procedure-related ischemic pain. PMID:20432349

  3. TU-F-CAMPUS-J-02: Evaluation of Textural Feature Extraction for Radiotherapy Response Assessment of Early Stage Breast Cancer Patients Using Diffusion Weighted MRI and Dynamic Contrast Enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Y; Wang, C; Horton, J; Chang, Z [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To investigate the feasibility of using classic textural feature extraction in radiotherapy response assessment, we studied a unique cohort of early stage breast cancer patients with paired pre - and post-radiation Diffusion Weighted MRI (DWI-MRI) and Dynamic Contrast Enhanced MRI (DCE-MRI). Methods: 15 female patients from our prospective phase I trial evaluating preoperative radiotherapy were included in this retrospective study. Each patient received a single-fraction radiation treatment, and DWI and DCE scans were conducted before and after the radiotherapy. DWI scans were acquired using a spin-echo EPI sequence with diffusion weighting factors of b = 0 and b = 500 mm{sup 2} /s, and the apparent diffusion coefficient (ADC) maps were calculated. DCE-MRI scans were acquired using a T{sub 1}-weighted 3D SPGR sequence with a temporal resolution of about 1 minute. The contrast agent (CA) was intravenously injected with a 0.1 mmol/kg bodyweight dose at 2 ml/s. Two parameters, volume transfer constant (K{sup trans} ) and k{sub ep} were analyzed using the two-compartment Tofts kinetic model. For DCE parametric maps and ADC maps, 33 textural features were generated from the clinical target volume (CTV) in a 3D fashion using the classic gray level co-occurrence matrix (GLCOM) and gray level run length matrix (GLRLM). Wilcoxon signed-rank test was used to determine the significance of each texture feature’s change after the radiotherapy. The significance was set to 0.05 with Bonferroni correction. Results: For ADC maps calculated from DWI-MRI, 24 out of 33 CTV features changed significantly after the radiotherapy. For DCE-MRI pharmacokinetic parameters, all 33 CTV features of K{sup trans} and 33 features of k{sub ep} changed significantly. Conclusion: Initial results indicate that those significantly changed classic texture features are sensitive to radiation-induced changes and can be used for assessment of radiotherapy response in breast cancer.

  4. Prospective Preference Assessment of Patients' Willingness to Participate in a Randomized Controlled Trial of Intensity-Modulated Radiotherapy Versus Proton Therapy for Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Anand [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Efstathiou, Jason A.; Paly, Jonathan J. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Halpern, Scott D. [Department of Medicine, University of Pennsylvania, Philadelphia, PA (United States); Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania, Philadelphia, PA (United States); Center for Bioethics, University of Pennsylvania, Philadelphia, PA (United States); Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA (United States); Bruner, Deborah W. [Winship Cancer Institute, Emory University, Atlanta, GA (United States); Christodouleas, John P. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Coen, John J. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Deville, Curtiland; Vapiwala, Neha [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Shipley, William U.; Zietman, Anthony L. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Hahn, Stephen M. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Bekelman, Justin E., E-mail: bekelman@uphs.upenn.edu [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA (United States); Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA (United States)

    2012-05-01

    Purpose: To investigate patients' willingness to participate (WTP) in a randomized controlled trial (RCT) comparing intensity-modulated radiotherapy (IMRT) with proton beam therapy (PBT) for prostate cancer (PCa). Methods and Materials: We undertook a qualitative research study in which we prospectively enrolled patients with clinically localized PCa. We used purposive sampling to ensure a diverse sample based on age, race, travel distance, and physician. Patients participated in a semi-structured interview in which they reviewed a description of a hypothetical RCT, were asked open-ended and focused follow-up questions regarding their motivations for and concerns about enrollment, and completed a questionnaire assessing characteristics such as demographics and prior knowledge of IMRT or PBT. Patients' stated WTP was assessed using a 6-point Likert scale. Results: Forty-six eligible patients (33 white, 13 black) were enrolled from the practices of eight physicians. We identified 21 factors that impacted patients' WTP, which largely centered on five major themes: altruism/desire to compare treatments, randomization, deference to physician opinion, financial incentives, and time demands/scheduling. Most patients (27 of 46, 59%) stated they would either 'definitely' or 'probably' participate. Seventeen percent (8 of 46) stated they would 'definitely not' or 'probably not' enroll, most of whom (6 of 8) preferred PBT before their physician visit. Conclusions: A substantial proportion of patients indicated high WTP in a RCT comparing IMRT and PBT for PCa.

  5. Parotid gland sparing radiotherapy

    NARCIS (Netherlands)

    Braam, P.M.

    2007-01-01

    Introduction Radiotherapy is a common form of treatment for head-and-neck malignancies. One of the most prominent complaints after radiotherapy is a dry mouth, which is caused by irradiation of the salivary glands. The main contributors of saliva during stimulation are the parotid glands, which are

  6. To study tumor motion and planning target volume margins using four dimensional computed tomography for cancer of the thorax and abdomen regions

    Directory of Open Access Journals (Sweden)

    Deshpande Sudesh

    2011-01-01

    Full Text Available In this study, four dimensional computed tomography (4DCT scanning was performed during free breathing on a 16-slice Positron emission tomography PET /computed tomography (CT for abdomen and thoracic patients. Images were sorted into 10 phases based on the temporal correlation between surface motion and data acquisition with an Advantage Workstation. Gross tumor volume gross tumor volume (GTV s were manually contoured on all 10 phases of the 4DCT scan. GTVs in the multiple CT phases were called GTV4D. GTV4D plus an isotropic margin of 1.0 cm was called CTV4D. Two sets of planning target volume (PTV 4D (PTV4D were derived from the CTV4D, i.e. PTV4D 2cm = CTV4D plus 1 cm setup margin (SM and 1 cm internal margin (IM and PTV4D 1.5cm = CTV4D plus 1 cm SM and 0.5cm IM. PTV3D was derived from a CTV3D of the helical CT scan plus conventional margins of 2 cm. PTV gated was generated only selecting three CT phases, with a total margin of 1.5 cm. All four volumes were compared. To quantify the extent of the motion, we selected the two phases where the tumor exhibited the greatest range of motion. We also studied the effect of different PTV volumes on dose to the surrounding critical structures. Volume of CTV4D was greater than that of CTV3D. We found, on an average, a reduction of 14% volume of PTV4D 1.5cm as compared with PTV3D and reduction of 10% volume of PTV gated as compared with PTV4D 1.5cm . We found that 2 cm of margin was inadequate if true motion of tumor was not known. We observed greater sparing of critical structures for PTVs drawn taking into account the tumor motion.

  7. Assessment of effectiveness of palliative radiotherapy in patients with advances neoplams of head and neck; Ocena skutecznosci paliatywnej radioterapii u chorych na zaawansowane nowotwory glowy i szyi

    Energy Technology Data Exchange (ETDEWEB)

    Cerkaska-Gluszak, B.; Wojciechowska-Lacka, A. [Wielkopolskie Centrum Onkologii, Wroclaw (Poland)

    1994-12-31

    The head and neck cancer morbidity grows systematically in Poland. However, the number of patients treated radically doesn`t`t grows parallerly. This is the reason why some patients are treated palliatively, first of all using radiotherapy. Limited number of radiation units leads to propose effective models of palliative radiotherapy including short time of hospitalization and high fraction dose. One of this models used in Radiotherapy Institute of Wielkopolski Center of Oncology includes high doses irradiation in short time with planned breaks. 94 patients underwent extern palliative radiation which have been observed during one year. Survival rate was 32/o. 12/o of patients kept partial regression of primary lesion. Our results are compared to results of others Oncological Centers. Efficacy of relieving ailments and good tolerance of treatment make this method useful. (author) 5 refs, 2 tabs

  8. Diffusion-weighted magnetic resonance imaging during radiotherapy of locally advanced cervical cancer--treatment response assessment using different segmentation methods.

    Science.gov (United States)

    Haack, Søren; Tanderup, Kari; Kallehauge, Jesper Folsted; Mohamed, Sandy Mohamed Ismail; Lindegaard, Jacob Christian; Pedersen, Erik Morre; Jespersen, Sune Nørhøj

    2015-01-01

    Diffusion-weighted magnetic resonance imaging (DW-MRI) and the derived apparent diffusion coefficient (ADC) value has potential for monitoring tumor response to radiotherapy (RT). Method used for segmentation of volumes with reduced diffusion will influence both volume size and observed distribution of ADC values. This study evaluates: 1) different segmentation methods; and 2) how they affect assessment of tumor ADC value during RT. Eleven patients with locally advanced cervical cancer underwent MRI three times during their RT: prior to start of RT (PRERT), two weeks into external beam RT (WK2RT) and one week prior to brachytherapy (PREBT). Volumes on DW-MRI were segmented using three semi-automatic segmentation methods: "cluster analysis", "relative signal intensity (SD4)" and "region growing". Segmented volumes were compared to the gross tumor volume (GTV) identified on T2-weighted MR images using the Jaccard similarity index (JSI). ADC values from segmented volumes were compared and changes of ADC values during therapy were evaluated. Significant difference between the four volumes (GTV, DWIcluster, DWISD4 and DWIregion) was found (p < 0.01), and the volumes changed significantly during treatment (p < 0.01). There was a significant difference in JSI among segmentation methods at time of PRERT (p < 0.016) with region growing having the lowest JSIGTV (mean± sd: 0.35 ± 0.1), followed by the SD4 method (mean± sd: 0.50 ± 0.1) and clustering (mean± sd: 0.52 ± 0.3). There was no significant difference in mean ADC value compared at same treatment time. Mean tumor ADC value increased significantly (p < 0.01) for all methods across treatment time. Among the three semi-automatic segmentations of hyper-intense intensities on DW-MR images implemented, cluster analysis and relative signal thresholding had the greatest similarity to the clinical tumor volume. Evaluation of mean ADC value did not depend on segmentation method.

  9. PET/CT and radiotherapy in prostate cancer

    NARCIS (Netherlands)

    De Jong, I. J.; De Haan, T. D.; Wiegman, E. M.; Van den Bergh, A. C. M.; Pruim, J.; Breeuwsma, J.

    2010-01-01

    Radiotherapy is one of the corner stone treatments for patients with prostate cancer. Especially for locally advanced tumors radiotherapy +/- adjuvant androgen deprivation treatment is standard of care. This brings up the need for accurate assessment of extra prostatic tumor growth and/or the

  10. Radiotherapy for pain management of bone metastases

    Energy Technology Data Exchange (ETDEWEB)

    Rezende Junior, Ismar de; Mattos, Marcos Duarte de; Nakamura, Ricardo; Lemes Junior, Joaquim; Vanzelli, Talita Lozano, E-mail: rezende.med@terra.com.br [Radioterapia do Hospital de Cancer de Barretos, SP (Brazil)

    2011-07-01

    Purpose: This is the first Brazilian study intended to evaluate the response of pain relief with radiotherapy in three different fractionation and the clinical differences in managing pain in patients with painful bone metastases. Methods: Prospective study of patients with painful bone metastases referred to the Radiotherapy Sector of the Hospital de Cancer de Barretos for pain-relieving radiotherapy between March and December 2010. It is known that radiotherapy seems to alter the activation of osteoclast-mediated bone resorption, relieving pain in cases of painful bone metastases. Patients were assessed in relation to the status of pain intensity before and after the initiation of radiotherapy. Either a single fraction of 8Gy, five fractions of 4Gy or ten fractions of 3Gy were given. A visual analog scale (VAS) was applied by doctors, nurses and nursing technicians to assess pain intensity at each session of radiotherapy, and follow-up at 8, 30 and 90 days from the end of treatment. Results: We evaluated 92 consecutive patients, 48 male and 44 female, with a median age of 58 years. We found that 14% of patients referred from the Palliative Care or Clinical Oncology sectors need better pharmacological analgesia due to severe pain, compared with 40.5% of patients from the other sectors (p = 0.004). We also found that the onset of pain relief to patients receiving 10 fractions of 300cGy analgesia without changing the pre-radiotherapy analgesia occurred with significance after the fifth fraction. Improvement in pain experienced within 90 days of follow-up was found in eighty percent of patients, independent of fractionated radiotherapy, site of metastases and the clinical condition of the patient. Discussion/Conclusion: The Palliative Care and Clinical Oncology sectors expressed greater concern in regards to analgesia for the patient with painful bone metastases. Radiotherapy is an effective pain-relieving treatment in different fractionation studied, even though the

  11. TU-C-17A-04: BEST IN PHYSICS (THERAPY) - A Supervised Framework for Automatic Contour Assessment for Radiotherapy Planning of Head- Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H; Kavanaugh, J; Tan, J; Dolly, S; Gay, H; Thorstad, W; Anastasio, M; Altman, M; Mutic, S; Li, H [Washington University School of Medicine, Saint Louis, MO (United States)

    2014-06-15

    Purpose: Precise contour delineation of tumor targets and critical structures from CT simulations is essential for accurate radiotherapy (RT) treatment planning. However, manual and automatic delineation processes can be error prone due to limitations in imaging techniques and individual anatomic variability. Tedious and laborious manual verification is hence needed. This study develops a general framework for automatically assessing RT contours for head-neck cancer patients using geometric attribute distribution models (GADMs). Methods: Geometric attributes (centroid and volume) were computed from physician-approved RT contours of 29 head-neck patients. Considering anatomical correlation between neighboring structures, the GADM for each attribute was trained to characterize intra- and interpatient structure variations using principal component analysis. Each trained GADM was scalable and deformable, but constrained by the principal attribute variations of the training contours. A new hierarchical model adaptation algorithm was utilized to assess the RT contour correctness for a given patient. Receiver operating characteristic (ROC) curves were employed to evaluate and tune system parameters for the training models. Results: Experiments utilizing training and non-training data sets with simulated contouring errors were conducted to validate the framework performance. Promising assessment results of contour normality/abnormality for the training contour-based data were achieved with excellent accuracy (0.99), precision (0.99), recall (0.83), and F-score (0.97), while corresponding values of 0.84, 0.96, 0.83, and 0.9 were achieved for the non-training data. Furthermore, the areas under the ROC curves were above 0.9, validating the accuracy of this test. Conclusion: The proposed framework can reliably identify contour normality/abnormality based upon intra- and inter-structure constraints derived from clinically-approved contours. It also allows physicians to

  12. Radiotherapy: An Update

    Directory of Open Access Journals (Sweden)

    Vikrant Kasat

    2010-01-01

    Full Text Available Radiotherapy is the art of using ionizing radiation to destroy malignant cells while minimizing damage to normal tissue. Radiotherapy has become a standard treatment option for a wide range of malignancies. Several new imaging techniques, both anatomical and functional are currently being evaluated as well as practiced for treatment planning of cancer. These recent developments have allowed radiation oncologists to escalate the dose of radiation delivered to tumors while minimizing the dose delivered to surrounding normal tissue. In this update, we attempt to pen down important aspects of radiotherapy.

  13. Radiotherapy dosimetry audit: three decades of improving standards and accuracy in UK clinical practice and trials.

    Science.gov (United States)

    Clark, Catharine H; Aird, Edwin G A; Bolton, Steve; Miles, Elizabeth A; Nisbet, Andrew; Snaith, Julia A D; Thomas, Russell A S; Venables, Karen; Thwaites, David I

    2015-01-01

    Dosimetry audit plays an important role in the development and safety of radiotherapy. National and large scale audits are able to set, maintain and improve standards, as well as having the potential to identify issues which may cause harm to patients. They can support implementation of complex techniques and can facilitate awareness and understanding of any issues which may exist by benchmarking centres with similar equipment. This review examines the development of dosimetry audit in the UK over the past 30 years, including the involvement of the UK in international audits. A summary of audit results is given, with an overview of methodologies employed and lessons learnt. Recent and forthcoming more complex audits are considered, with a focus on future needs including the arrival of proton therapy in the UK and other advanced techniques such as four-dimensional radiotherapy delivery and verification, stereotactic radiotherapy and MR linear accelerators. The work of the main quality assurance and auditing bodies is discussed, including how they are working together to streamline audit and to ensure that all radiotherapy centres are involved. Undertaking regular external audit motivates centres to modernize and develop techniques and provides assurance, not only that radiotherapy is planned and delivered accurately but also that the patient dose delivered is as prescribed.

  14. Assessment of Monte Carlo algorithm for compliance with RTOG 0915 dosimetric criteria in peripheral lung cancer patients treated with stereotactic body radiotherapy.

    Science.gov (United States)

    Pokhrel, Damodar; Sood, Sumit; Badkul, Rajeev; Jiang, Hongyu; McClinton, Christopher; Lominska, Christopher; Kumar, Parvesh; Wang, Fen

    2016-05-08

    The purpose of the study was to evaluate Monte Carlo-generated dose distributions with the X-ray Voxel Monte Carlo (XVMC) algorithm in the treatment of peripheral lung cancer patients using stereotactic body radiotherapy (SBRT) with non-protocol dose-volume normalization and to assess plan outcomes utilizing RTOG 0915 dosimetric compliance criteria. The Radiation Therapy Oncology Group (RTOG) protocols for non-small cell lung cancer (NSCLC) currently require radiation dose to be calculated using tissue density heterogeneity corrections. Dosimetric criteria of RTOG 0915 were established based on superposition/convolution or heterogeneities corrected pencil beam (PB-hete) algorithms for dose calculations. Clinically, more accurate Monte Carlo (MC)-based algorithms are now routinely used for lung stereotactic body radiotherapy (SBRT) dose calculations. Hence, it is important to determine whether MC calculations in the delivery of lung SBRT can achieve RTOG standards. In this report, we evaluate iPlan generated MC plans for peripheral lung cancer patients treated with SBRT using dose-volume histogram (DVH) normalization to determine if the RTOG 0915 compliance criteria can be met. This study evaluated 20 Stage I-II NSCLC patients with peripherally located lung tumors, who underwent MC-based SBRT with heterogeneity correction using X-ray Voxel Monte Carlo (XVMC) algorithm (Brainlab iPlan version 4.1.2). Total dose of 50 to 54 Gy in 3 to 5 fractions was delivered to the planning target vol-ume (PTV) with at least 95% of the PTV receiving 100% of the prescription dose (V100% ≥ 95%). The internal target volume (ITV) was delineated on maximum intensity projection (MIP) images of 4D CT scans. The PTV included the ITV plus 5 mm uniform margin applied to the ITV. The PTV ranged from 11.1 to 163.0 cc (mean = 46.1 ± 38.7 cc). Organs at risk (OARs) including ribs were delineated on mean intensity projection (MeanIP) images of 4D CT scans. Optimal clinical MC SBRT plans were

  15. Assessment of the radioprotective effect of propolis in breast cancer patients undergoing radiotherapy. New perspective for an old honey bee product

    Directory of Open Access Journals (Sweden)

    Samia A. Ebeid

    2016-10-01

    Conclusions: Supplementation of propolis with radiotherapy treatment offers a quite measurable protection against DNA damage caused by ionizing radiation in BC patients leukocytes and inhibits RRM2 overexpression. Moreover, propolis has beneficial effects on the serum antioxidant capacity and improves the digestive utilization of iron and the regeneration efficiency of hemoglobin. Larger prospective studies are required to confirm our findings.

  16. [Radiotherapy of skin cancers].

    Science.gov (United States)

    Hennequin, C; Rio, E; Mahé, M-A

    2016-09-01

    The indications of radiotherapy for skin cancers are not clearly defined because of the lack of randomised trials or prospective studies. For basal cell carcinomas, radiotherapy frequently offers a good local control, but a randomized trial showed that surgery is more efficient and less toxic. Indications of radiotherapy are contra-indications of surgery for patients older than 60, non-sclerodermiform histology and occurring in non-sensitive areas. Adjuvant radiotherapy could be proposed to squamous cell carcinomas, in case of poor prognostic factors. Dose of 60 to 70Gy are usually required, and must be modulated to the size of the lesions. Adjuvant radiotherapy seems beneficial for desmoplastic melanomas but not for the other histological types. Prophylactic nodal irradiation (45 to 50Gy), for locally advanced tumours (massive nodal involvement), decreases the locoregional failure rate but do not increase survival. Adjuvant radiotherapy (50 to 56Gy) for Merckel cell carcinomas increases also the local control rate, as demonstrated by meta-analysis and a large epidemiological study. Nodal areas must be included, if there is no surgical exploration (sentinel lymph node dissection). Kaposi sarcomas are radiosensitive and could be treated with relatively low doses (24 to 30Gy). Also, cutaneous lymphomas are good indications for radiotherapy: B lymphomas are electively treated with limited fields. The role of total skin electron therapy for T-lymphomas is still discussed; but palliative radiotherapy is very efficient in case of cutaneous nodules. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  17. Updates on clinical studies of selenium supplementation in radiotherapy.

    Science.gov (United States)

    Puspitasari, Irma M; Abdulah, Rizky; Yamazaki, Chiho; Kameo, Satomi; Nakano, Takashi; Koyama, Hiroshi

    2014-05-29

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200-500 μg/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation.

  18. Updates on clinical studies of selenium supplementation in radiotherapy

    Science.gov (United States)

    2014-01-01

    To establish guidelines for the selenium supplementation in radiotherapy we assessed the benefits and risks of selenium supplementation in radiotherapy. Clinical studies on the use of selenium in radiotherapy were searched in the PubMed electronic database in January 2013. Sixteen clinical studies were identified among the 167 articles selected in the initial search. Ten articles were observational studies, and the other 6 articles reported studies on the effects of selenium supplementation in patients with cancer who underwent radiotherapy. The studies were conducted worldwide including European, American and Asian countries between 1987 and 2012. Plasma, serum or whole blood selenium levels were common parameters used to assess the effects of radiotherapy and the selenium supplementation status. Selenium supplementation improved the general conditions of the patients, improved their quality of life and reduced the side effects of radiotherapy. At the dose of selenium used in these studies (200–500 μg/day), selenium supplementation did not reduce the effectiveness of radiotherapy, and no toxicities were reported. Selenium supplementation may offer specific benefits for several types of cancer patients who undergo radiotherapy. Because high-dose selenium and long-term supplementation may be unsafe due to selenium toxicity, more evidence-based information and additional research are needed to ensure the therapeutic benefits of selenium supplementation. PMID:24885670

  19. Impaired anastomotic healing after preoperative radiotherapy ...

    African Journals Online (AJOL)

    Background. Patients with rectal carcinoma undergoing total mesorectal excision (TME) have a lower recurrence rate with preoperative radiotherapy (RT). The aim of this study was to assess the side-effects in patients who had preoperative RT compared with those who did not receive it (because of palliative resections, ...

  20. Effects of Yifukang Oral Liquid on Chemotherapy- and Radiotherapy ...

    African Journals Online (AJOL)

    Purpose: To investigate the effects of Yifukang oral liquid (YFKOL) on chemotherapy- and radiotherapy-induced myelosuppression, leucopenia and gastrointestinal tract disturbances. Methods: The effects of YFKOL on myelosuppression, leucopenia and gastrointestinal tract disturbances were assessed by ...

  1. Translation and cross-cultural adaptation into Brazilian Portuguese of the Vanderbilt Head and Neck Symptom Survey version 2.0 (VHNSS 2.0) for the assessment of oral symptoms in head and neck cancer patients submitted to radiotherapy.

    Science.gov (United States)

    Barroso, Eliane Marçon; Carvalho, André Lopes; Paiva, Carlos Eduardo; Nunes, João Soares; Paiva, Bianca Sakamoto Ribeiro

    2015-01-01

    Patients submitted to radiotherapy for the treatment of head and neck cancer have several symptoms, predominantly oral. The Vanderbilt Head and Neck Symptom Survey version 2.0 is an American tool developed to evaluate oral symptoms in head and neck cancer patients submitted to radiotherapy. The aim of the present study was to translate the Vanderbilt Head and Neck Symptom Survey version 2.0 into Brazilian Portuguese and cross-culturally adapt this tool for subsequent validation and application in Brazil. A method used for the translation and cultural adaptation of tools, which included independent translations, synthesis of the translations, back-translations, expert committee, and pre-test, was used. The pre-test was performed with 37 head and neck cancer patients, who were divided into four groups, to assess the relevance and understanding of the assessed items. Data were submitted to descriptive statistical analysis. The overall mean of the content validity index was 0.79 for semantic and idiomatic equivalence, and it was higher than 0.8 for cultural and conceptual equivalence. The cognitive interview showed that patients were able to paraphrase the items, and considered them relevant and easily understood. The tool was translated and cross-culturally adapted to be used in Brazil. The authors believe this translation is suited for validation. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  2. Translation and cross-cultural adaptation into Brazilian Portuguese of the Vanderbilt Head and Neck Symptom Survey version 2.0 (VHNSS 2.0 for the assessment of oral symptoms in head and neck cancer patients submitted to radiotherapy

    Directory of Open Access Journals (Sweden)

    Eliane Marçon Barroso

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Patients submitted to radiotherapy for the treatment of head and neck cancer have several symptoms, predominantly oral. The Vanderbilt Head and Neck Symptom Survey version 2.0 is an American tool developed to evaluate oral symptoms in head and neck cancer patients submitted to radiotherapy. OBJECTIVE: The aim of the present study was to translate the Vanderbilt Head and Neck Symptom Survey version 2.0 into Brazilian Portuguese and cross-culturally adapt this tool for subsequent validation and application in Brazil. METHODS: A method used for the translation and cultural adaptation of tools, which included independent translations, synthesis of the translations, back-translations, expert committee, and pre-test, was used. The pre-test was performed with 37 head and neck cancer patients, who were divided into four groups, to assess the relevance and understanding of the assessed items. Data were submitted to descriptive statistical analysis. RESULTS: The overall mean of the content validity index was 0.79 for semantic and idiomatic equivalence, and it was higher than 0.8 for cultural and conceptual equivalence. The cognitive interview showed that patients were able to paraphrase the items, and considered them relevant and easily understood. CONCLUSION: The tool was translated and cross-culturally adapted to be used in Brazil. The authors believe this translation is suited for validation.

  3. Nanoparticle-guided radiotherapy

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing for simult......The present invention relates to a method and nano-sized particles for image guided radiotherapy (IGRT) of a target tissue. More specifically, the invention relates to nano-sized particles comprising X-ray-imaging contrast agents in solid form with the ability to block x-rays, allowing...... for simultaneous or integrated external beam radiotherapy and imaging, e.g., using computed tomography (CT)....

  4. Haemorrhagic cystitis after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    1987-02-07

    Sterile hemorrhagic cystitis may occur during or immediately after radiotherapy; a frequency of 4.6% has been reported at up to four weeks from the completion of 60-80 Gy. It is usually self-limiting. The frequency of late hemorrhagic cystitis is reported to be 2-9%, although less severe bleeding must be commoner. Combination of pelvic radiotherapy with systemic cyclophosphamide greatly increases the risk of serious bleeding, with a frequency of 18% being reported in one series of children. This note outlines the various treatment options, involving both drugs and surgery.

  5. Xerostomia induced by radiotherapy

    Directory of Open Access Journals (Sweden)

    Alimi D

    2015-08-01

    Full Text Available David Alimi Department of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA, USAWe read with great interest the excellent review on xerostomia induced by radiotherapy, by Pinna et al.1 The authors should be congratulated for a very detailed review of the physiopathology, clinical symptoms, and therapeutic management of an extremely difficult condition. Although we agree that the use of anticholinergic medication represents treatment, it requires the patient to have residual salivary gland function. Unfortunately, it is well established that in most cases radiotherapy destroys most of the salivary gland and associated salivary secretions.     

  6. Development of evaluation and performance verification technology for radiotherapy radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J. Y.; Jang, S. Y.; Kim, B. H. and others

    2005-02-15

    No matter how much the importance is emphasized, the exact assessment of the absorbed doses administered to the patients to treat the various diseases such as lately soaring malignant tumors with the radiotherapy practices is the most important factor. In reality, several over-exposed patients from the radiotherapy practice become very serious social issues. Especially, the development of a technology to exactly assess the high doses and high energies (In general, dose administered to the patients with the radiotherapy practices are very huge doses, and they are about three times higher than the lethal doses) generated by the radiation generators and irradiation equipment is a competing issue to be promptly conducted. Over fifty medical centers in Korea operate the radiation generators and irradiation equipment for the radiotherapy practices. However, neither the legal and regulatory systems to implement a quality assurance program are sufficiently stipulated nor qualified personnel who could run a program to maintain the quality assurance and control of those generators and equipment for the radiotherapy practices in the medical facilities are sufficiently employed. To overcome the above deficiencies, a quality assurance program such as those developed in the technically advanced countries should be developed to exactly assess the doses administered to patients with the radiotherapy practices and develop the necessary procedures to maintain the continuing performance of the machine or equipment for the radiotherapy. The QA program and procedures should induce the fluent calibration of the machine or equipment with quality, and definitely establish the safety of patients in the radiotherapy practices. In this study, a methodology for the verification and evaluation of the radiotherapy doses is developed, and several accurate measurements, evaluations of the doses delivered to patients and verification of the performance of the therapy machine and equipment are

  7. Palliative radiotherapy and oncology nursing.

    Science.gov (United States)

    McMenamin, Erin; Ross, Nicole; Jones, Joshua

    2014-11-01

    To describe indications and expected outcomes for palliative radiotherapy and to highlight opportunities for nurse involvement in palliative radiotherapy. Journal articles, clinical guidelines, case studies. Palliative radiotherapy is a safe, effective treatment modality for many symptoms of advanced cancer. Opportunities exist to help patients and families opt for shorter palliative radiotherapy courses when quality of life is the goal. Nurses involved in the care of patients receiving palliative radiotherapy must be aware of the indications and expected outcomes associated with therapy. Nurses can play an important role in the management of symptoms, education, and communication between the team and the patient and family.

  8. [Radiotherapy for intrathoracic metastases].

    Science.gov (United States)

    Giraud, P; Lacornerie, T; Mornex, F

    2016-09-01

    Indication, doses, and technique of radiotherapy, for intrathoracic metastases are presented. The recommendations for delineation of the target volumes and organs at risk are detailed. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  9. Innovations in Radiotherapy Technology.

    Science.gov (United States)

    Feain, I J; Court, L; Palta, J R; Beddar, S; Keall, P

    2017-02-01

    Many low- and middle-income countries, together with remote and low socioeconomic populations within high-income countries, lack the resources and services to deal with cancer. The challenges in upgrading or introducing the necessary services are enormous, from screening and diagnosis to radiotherapy planning/treatment and quality assurance. There are severe shortages not only in equipment, but also in the capacity to train, recruit and retain staff as well as in their ongoing professional development via effective international peer-review and collaboration. Here we describe some examples of emerging technology innovations based on real-time software and cloud-based capabilities that have the potential to redress some of these areas. These include: (i) automatic treatment planning to reduce physics staffing shortages, (ii) real-time image-guided adaptive radiotherapy technologies, (iii) fixed-beam radiotherapy treatment units that use patient (rather than gantry) rotation to reduce infrastructure costs and staff-to-patient ratios, (iv) cloud-based infrastructure programmes to facilitate international collaboration and quality assurance and (v) high dose rate mobile cobalt brachytherapy techniques for intraoperative radiotherapy. Copyright © 2016 The Royal College of Radiologists. All rights reserved.

  10. [Radiotherapy of oropharynx carcinoma].

    Science.gov (United States)

    Servagi Vernat, S; Tochet, F; Vieillevigne, L; Pointreau, Y; Maingon, P; Giraud, P

    2016-09-01

    Indication, doses, technique of radiotherapy and concomitant chemotherapy for oropharynx carcinoma are presented. The recommendations for delineation of the target volumes and organs at risk are detailed. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  11. Neurocognitive Effects of Radiotherapy

    Science.gov (United States)

    2014-10-01

    investigates the effect of radiotherapy using serial MRI imaging and a series of neuropsychological measurements on two groups of patients; (1) those with...demonstrated a significant change over time in the RT- treated group, although a comprehensive neuropsychological battery of repeatable measures...woman of child -bearing potential, a negative pregnancy test (urine) will be required before participation in this study. ABNORMAL FINDINGS

  12. Role of radiotherapy fractionation in head and neck cancers (MARCH): An updated meta-analysis

    DEFF Research Database (Denmark)

    Lacas, Benjamin; Bourhis, Jean; Overgaard, Jens

    2017-01-01

    BACKGROUND: The Meta-Analysis of Radiotherapy in squamous cell Carcinomas of Head and neck (MARCH) showed that altered fractionation radiotherapy is associated with improved overall and progression-free survival compared with conventional radiotherapy, with hyperfractionated radiotherapy showing...... the greatest benefit. This update aims to confirm and explain the superiority of hyperfractionated radiotherapy over other altered fractionation radiotherapy regimens and to assess the benefit of altered fractionation within the context of concomitant chemotherapy with the inclusion of new trials. METHODS......: For this updated meta-analysis, we searched bibliography databases, trials registries, and meeting proceedings for published or unpublished randomised trials done between Jan 1, 2009, and July 15, 2015, comparing primary or postoperative conventional fractionation radiotherapy versus altered fractionation...

  13. The impact of computed tomography slice thickness on the assessment of stereotactic, 3D conformal and intensity-modulated radiotherapy of brain tumors.

    Science.gov (United States)

    Caivano, R; Fiorentino, A; Pedicini, P; Califano, G; Fusco, V

    2014-05-01

    To evaluate radiotherapy treatment planning accuracy by varying computed tomography (CT) slice thickness and tumor size. CT datasets from patients with primary brain disease and metastatic brain disease were selected. Tumor volumes ranging from about 2.5 to 100 cc and CT scan at different slice thicknesses (1, 2, 4, 6 and 10 mm) were used to perform treatment planning (1-, 2-, 4-, 6- and 10-CT, respectively). For any slice thickness, a conformity index (CI) referring to 100, 98, 95 and 90 % isodoses and tumor size was computed. All the CI and volumes obtained were compared to evaluate the impact of CT slice thickness on treatment plans. The smallest volumes reduce significantly if defined on 1-CT with respect to 4- and 6-CT, while the CT slice thickness does not affect target definition for the largest volumes. The mean CI for all the considered isodoses and CT slice thickness shows no statistical differences when 1-CT is compared to 2-CT. Comparing the mean CI of 1- with 4-CT and 1- with 6-CT, statistical differences appear only for the smallest volumes with respect to 100, 98 and 95 % isodoses-the CI for 90 % isodose being not statistically significant for all the considered PTVs. The accuracy of radiotherapy tumor volume definition depends on CT slice thickness. To achieve a better tumor definition and dose coverage, 1- and 2-CT would be suitable for small targets, while 4- and 6-CT are suitable for the other volumes.

  14. Associations between nutritional status, weight loss, radiotherapy treatment toxicity and treatment outcomes in gastrointestinal cancer patients.

    Science.gov (United States)

    Hill, Amanda; Kiss, Nicole; Hodgson, Belinda; Crowe, Timothy C; Walsh, Adam D

    2011-02-01

    Patients with gastrointestinal cancers are susceptible to nutritional deterioration which may be compounded by radiotherapy treatment toxicities. This study aimed to determine whether nutritional status at radiotherapy commencement or changes in nutritional status throughout radiotherapy were associated with treatment toxicity and outcomes in gastrointestinal cancer patients. Seventy-three gastrointestinal cancer patients receiving curative radiotherapy underwent medical record audits assessing body weight, radiotherapy toxicity, unplanned treatment breaks or hospital admissions and completion of prescribed treatment/s. Nutritional status was assessed in a subset of patients (n = 11) using the Patient-Generated Subjective Global Assessment tool. Seventy-five percent of patients lost weight throughout radiotherapy. Weight loss was significantly greater in patients experiencing unplanned radiotherapy breaks (-3.1% vs -1.6%, p nutritional status during radiotherapy (as measured by weight loss) may be associated with poorer short-term treatment outcomes in gastrointestinal cancer patients. Patient numbers were too small to definitively determine the effect of nutritional status at radiotherapy commencement or changes in nutritional status throughout radiotherapy (defined by PG-SGA) on treatment outcomes. Further research is required to investigate this in larger, longer-term studies. Copyright © 2010. Published by Elsevier Ltd.

  15. Assessment of quality of life and changes in body composition in men with localized prostate cancer on hormone therapy combined with radiotherapy prostate cancer, quality of life, body composition

    Energy Technology Data Exchange (ETDEWEB)

    Pires, Daniele de Campos; Salvajoli, Joao Victor; Gagliardi, Joao Fernando; Evangelista, Alexandre Lopes; Lopes, Charles Ricardo; Cruz, Ticiane

    2014-07-01

    Objective: the aim of this study was to evaluate the quality of life and changes in body composition in adult men (71.3 ± 6.9 years) with prostate cancer on hormone therapy combined with radiotherapy. Methodology: to assess the quality of life of individuals, we used the 36-Item Short Form Health Survey (SF-36), which is a tool developed to survey health status in the Medical Outcomes Study. This questionnaire was applied at the beginning and six months after the start of the study. Weight was measured and the percentage of fat was estimated from an anthropometric equation from Jackson and Pollock (1978). The period of assessments and reassessments was September 2009 to October 2010. Radiotherapy was performed in other hospitals (information contained in participant's data form), as the management of patients was conducted at the oncology pharmacy of Varzea do Carmo Specialties Clinic. Results: of the eight domains of the SF-36 questionnaire, five were worse with significant differences from the first to the second assessment. They are: overall health status (p <0.01), vitality (p <0.01), functional capacity (p <0.01), social functioning (p <0.01) and pain (p <0, 01). Body weight ranged statistically significant (p <0.01) between the first evaluation (75.3 ± 12.5kg) and the second evaluation (77.4 ± 12.5kg). The same occurred with the percentage of fat, where the initial values (25.1 ± 3.8%) and final (25.8 ± 3.5%) experienced statistically significant difference (p <0.01). Conclusion: the results of this study showed that hormone therapy combined with radiotherapy led to a gain of weight and body fat percentage in the men evaluated, as well as deterioration in the quality of life of these patients. Therefore, it is necessary to continue researching this topic in order to develop strategies that mitigate the side effects of hormone therapy. The risks of hormone therapy should be evaluated and compared with gains in order to define the length of treatment

  16. Symptomatic vertebral hemangioma: Treatment with radiotherapy

    Directory of Open Access Journals (Sweden)

    Aich Ranen

    2010-01-01

    Full Text Available Background: Vertebrae are the second commonest site among skeletal locations affected by hemangioma, but only about one per cent becomes symptomatic throughout the life. Though surgery, intra vertebral injection of various sclerosing agents have been tried in treating this benign process, no general consensus regarding management has been reached. Radiotherapy is emerging as a low cost, simple, non-invasive but very effective modality of treatment of symptomatic vertebral hemangioma. Aim: This study aims to find out the role of external beam radiotherapy in alleviating the symptoms of symptomatic vertebral hemangiomas without compromising the quality of life. Materials and Methods: Seven consecutive patients with symptomatic vertebral hemangioma were treated with a fixed dose of external beam radiotherapy; and muscle power was assessed before, after treatment and during follow-up. Results: All patients showed improvement of muscle power, which increased with the passage of time. Pain relief with improvement of quality of life was obtained in all the patients. Conclusion: Effect of radiotherapy on vertebral hemangioma is dose-dependent and the dose limiting factor is the spinal cord tolerance. In the present era of IMRT, greater dose can be delivered to the parts of vertebra affected by the hemangioma without compromising the spinal cord tolerance and expected to give better results.

  17. Radiotherapy reduces sialorrhea in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Neppelberg, E; Haugen, D F; Thorsen, L; Tysnes, O-B

    2007-12-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder. Sialorrhea is a frequent problem in ALS patients with bulbar symptoms, because of progressive weakness of oral, lingual and pharyngeal muscles. This prospective study aimed to investigate the putative effect of palliative single-dose radiotherapy on problematic sialorrhea in patients with ALS. Twenty patients with ALS and problematic drooling were included; 14 were given radiotherapy with a single fraction of 7.5 Grey (Gy). Five patients were treated with botulinum toxin A (BTX-A) injections (20 U) into the parotid glands; two of these were later given radiotherapy. Symptom assessment, clinical examination and measurements of salivary flow (ml/min) were performed before and after treatment (1-2 weeks, 3 months). Salivary secretion was significantly reduced after radiation treatment, with a mean reduction of 60% (1 week) and 51% (2 weeks). Three months post-treatment, 21% reduction of the salivary secretion was observed compared with salivation before treatment. Mean salivary flow was not reduced after BTX-A treatment in five patients. No serious side-effects were observed with either of the two treatment modalities. Single-dose radiotherapy (7.5 Gy) significantly reduces sialorrhea and is an effective and safe palliative treatment in patients with ALS.

  18. SU-G-JeP4-01: An Assessment of a Microsoft Kinect V2 Sensor for Voluntary Breath-Hold Monitoring in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Edmunds, D; Donovan, E [The Royal Marsden NHS Foundation Trust, Sutton, London (United Kingdom)

    2016-06-15

    Purpose: To determine whether the Microsoft Kinect Version 2 (Kinect v2), a commercial off-the-shelf (COTS) depth sensors designed for entertainment purposes, were robust to the radiotherapy treatment environment and could be suitable for monitoring of voluntary breath-hold compliance. This could complement current visual monitoring techniques, and be useful for heart sparing left breast radiotherapy. Methods: In-house software to control Kinect v2 sensors, and capture output information, was developed using the free Microsoft software development kit, and the Cinder creative coding C++ library. Each sensor was used with a 12m USB 3.0 active cable. A solid water block was used as the object. The depth accuracy and precision of the sensors was evaluated by comparing Kinect reported distance to the object with a precision laser measurement across a distance range of 0.6m to 2.0 m. The object was positioned on a high-precision programmable motion platform and moved in two programmed motion patterns and Kinect reported distance logged. Robustness to the radiation environment was tested by repeating all measurements with a linear accelerator operating over a range of pulse repetition frequencies (6Hz to 400Hz) and dose rates 50 to 1500 monitor units (MU) per minute. Results: The complex, consistent relationship between true and measured distance was unaffected by the radiation environment, as was the ability to detect motion. Sensor precision was < 1 mm and the accuracy between 1.3 mm and 1.8 mm when a distance correction was applied. Both motion patterns were tracked successfully with a root mean squared error (RMSE) of 1.4 and 1.1 mm respectively. Conclusion: Kinect v2 sensors are capable of tracking pre-programmed motion patterns with an accuracy <2 mm and appear robust to the radiotherapy treatment environment. A clinical trial using Kinect v2 sensor for monitoring voluntary breath hold has ethical approval and is open to recruitment. The authors are supported by a

  19. Radiotherapy for T1-2N0 glottic cancer: a multivariate analysis of predictive factors for the long-term outcome in 1050 patients and a prospective assessment of quality of life and voice handicap index in a subset of 233 patients.

    Science.gov (United States)

    Al-Mamgani, A; van Rooij, P H; Woutersen, D P; Mehilal, R; Tans, L; Monserez, D; Baatenburg de Jong, R J

    2013-08-01

    To evaluate the outcomes of patients with early stage glottic cancer (GC) treated with radiotherapy (RT). The current study report on a retrospective analysis of oncologic outcome of 1050 patients with T1-2N0 glottic cancer treated with radiotherapy. Prospective assessment of quality of life (QoL) and voice handicap index (VHI) was performed in all patients treated from 2006 onwards (n = 233). Local control (LC), regional control (RC), disease-free survival (DFS), overall survival (OS), quality of life and voice handicap index. After a median follow-up of 90 months (range 3-309), the actuarial rates of local control, regional control, disease-free survival and overall survival were 85%, 99%, 84% and 81% at 5 years and 82%, 98%, 80% and 61% at 10 years, respectively. On multivariate analysis, T2 tumours, smoking after radiotherapy and conventional radiation scheme correlated significantly with poor local control. Patients who continued smoking after radiotherapy had also significantly lower overall survival rates (OR 4.3, P handicap index improved significantly from 37 at baseline to 18 at 48 months. Patients with T2b and those who continued smoking had significantly worse voice handicap index. In the current study, excellent outcome with good quality of life and voice handicap index scores were reported. T2 tumours, in particular T2b, and continuing smoking after radiotherapy correlated significantly with poor local control and worse voice handicap index. © 2013 John Wiley & Sons Ltd.

  20. Long-term results of radiotherapy for pituitary adenomas. Evaluation of tumor control and hypopituitarism after radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchida, Emiko; Sakai, Kunio; Matsumoto, Yasuo; Sugita, Tadashi; Sasamoto, Ryuta [Niigata Univ. (Japan). School of Medicine

    1999-09-01

    To evaluate the results of conventional radiotherapy for pituitary adenomas assessed with computed tomography (CT) or magnetic resonance imaging (MRI). Endpoints include tumor control, normalization of hormone levels in functioning adenomas, and hypopituitarism after radiotherapy as an adverse effect. Forty-two patients were treated with radiotherapy from 1982 to 1995 at Niigata University Hospital. Forty patients were irradiated after surgery because of residual adenomas in 33 patients and tumor regrowth in 7 patients. One patient was treated with radiotherapy alone, and the remaining 1 patient was treated with preoperative radiotherapy. Tumor size and extension were evaluated using CT or MRI, and all tumors were macroadenomas. They consisted of 18 non-functioning and 24 functioning adenomas (growth hormone (GH)-secreting: 11, prolactinomas: 7, concomitant GH and prolactin (PRL)-secreting: 5, gonadotropin-secreting: 1). Treatment was given in 200 cGy daily fraction size and a total dose of 50 Gy was given to most patients. Sixteen patients with GH- and/or PRL-secreting adenomas received bromocriptine. Tumor progression was determined by increase in tumor size as shown by CT or MRI. Hypopituitarism after radiotherapy was evaluated using the functions of corticotropin (ACTH), thyrotropin (TSH), and gonadotropin. Median follow-up time from the end of radiotherapy was 103 months. Tumor progression occurred in 2 out of 42 patients and 10-year progression-free rate for all patients was 93.7%. Normalization of GH levels was obtained in 12 of 16 GH-secreting adenomas with a mean time of 27 months after radiotherapy, and 9 of 12 PRL-secreting adenomas achieved normalization of PRL levels with a mean time of 34 months. One gonadotropin-secreting adenoma achieved normalization of gonadotropin level at 21 months after radiotherapy. The incidence of hypopituitarism after radiotherapy increased with time, and cumulative risk of deficiencies of ACTH, TSH, and gonadotropin at 10

  1. Differential risk assessments from five hypoxia specific assays: The basis for biologically adapted individualized radiotherapy in advanced head and neck cancer patients

    DEFF Research Database (Denmark)

    Nordsmark, Marianne; Eriksen, Jesper Grau; Gebski, Val

    2007-01-01

    osteopontin measured by ELISA, tumour oxygenation status using pO(2) needle electrodes and tumour osteopontin, hypoxia inducible factor 1alpha (HIF-1alpha) and carboxyanhydrase 9 (CA9) by immunohistochemistry. The primary treatment was radiotherapy and the hypoxic radiosensitizer nimorazole. Loco......-regional tumour control was evaluated at 5 years. RESULTS: All five markers showed inter-tumour variability. Inter-marker correlations were inconsistent. Only plasma osteopontin inversely correlated with median tumour pO(2), (p=0.02, r=0.28) and CA9 correlated with HIF-1alpha (p...-Meier analysis high plasma osteopontin, high HIF-1alpha and high proportion of tumour pO(2)2.5mmHg (HP(2.5)) related significantly with poorer loco-regional control, whereas CA9 and tumour osteopontin failed to predict loco-regional control in this set dataset. When analyzing Hb, stage, and the five markers...

  2. Serial assessment of FDG-PET FDG uptake and functional volume during radiotherapy (RT) in patients with non-small cell lung cancer (NSCLC).

    Science.gov (United States)

    Edet-Sanson, Agathe; Dubray, Bernard; Doyeux, Kaya; Back, Adeline; Hapdey, Sebastien; Modzelewski, Romain; Bohn, Pierre; Gardin, Isabelle; Vera, Pierre

    2012-02-01

    The objectives were (i) to confirm that diagnostic FDG-PET images could be obtained during thoracic radiotherapy, (ii) to verify that significant changes in FDG uptake or volume could be measured early enough to adapt the radiotherapy plan and (iii) to determine an optimal time window during the radiotherapy course to acquire a single FDG-PET examination that would be representative of tumour response. Ten non-small cell lung carcinoma (NSCLC) patients with significant PET/CT-FDG tumour radioactivity uptake (versus the background level), candidates for curative radiotherapy (RT, n=4; 60-70 Gy, 2 Gray per fraction, 5 fractions per week) or RT plus chemotherapy (CT-RT, n=6), were prospectively evaluated. Using a Siemens Biograph, 5 or 6 PET/CT scans (PET(n), n=0-5) were performed for each patient. Each acquisition included a 15-min thoracic PET with respiratory gating (RG) 60±5 min post-injection of the FDG (3.5 MBq/kg), followed by a standard, 5-min non-gated (STD) thoracic PET. PET(0) was performed before the first RT fraction. During RT, PET(1-5) were performed every 7 fractions, i.e., at 14 Gy total dose increment. FDG uptake was measured as the variation of SUV(max,PETn) versus SUV(max,PET0). Each lesions' volume was measured by (i) visual delineation by an experienced nuclear physician, (ii) 40% SUV(max) fixed threshold and (iii) a semi-automatic adaptive threshold method. A total of 53 FDG-PET scans were acquired. Seventeen lesions (6 tumours and 11 nodes) were visible on PET(0) in the 10 patients. The lesions were located either in or near the mediastinum or in the apex, without significant respiratory displacements at visual inspection of the gated images. Healthy lung did not cause motion artefacts in the PET images. As measured on 89 lesions, both the absolute and relative SUV(max) values decreased as the RT dose increased. A 50% SUV(max) decrease was obtained around a total dose of 45 Gy. Out of the 89 lesions, 75 remained visually identifiable during

  3. [Intraoperative radiotherapy. Preliminary results].

    Science.gov (United States)

    Maingon, P; Fraisse, J; Brun, O; Salas, S; Naudy, S; Bernard, A; Goudet, P; Chalencon, J L; Minello, C; Pillet, M

    1995-01-01

    We report a series of 40 patients treated by intraoperative radiotherapy between 1988 and 1992 (18 primary tumors, 13 local recurrences and 9 nodal extensions). The doses delivered were 15 Gy to 25 Gy, completed by external radiotherapy (15 to 45 Gy) in 13 cases. The local tumor control rate was 61% for initial therapy in primary tumors (70% for adenocarcinoma of the stomach) and 80.9% after complete en bloc surgery. The local control rate after palliative surgery for local recurrences is 38% and 33% for nodal extension. Two patients died (5%) during the postoperative period. We observed 2 hemorrhages and 3 cases of stone-free cholecystitis. The value of this approach must be confirmed in rigorous indications in comparison with surgery alone in controlled and randomised clinical trials.

  4. Radiotherapy of hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Gauwerky, F.

    1982-10-11

    The findings about the regular, spontaneous and complete regression of cavernous skin hemangiomas occurring in infants and those findings about the damaging effects due to ionising radiation - here particularly local growth disturbances - led to the development of very cautious diagnostic methods and to a considerate individual dosage and radiotherapy, which always takes into consideration the spontaneous regression tendency of the hemangiomas. However, a function-impairing localisation at the orifices, fulminant macrosomia, tendency to hemorrhages and poly-infection with superficial ulceration and even thrombopenic syndromes of the Kasabach-Merritt type may become necessary, urgent and also vital indications for a particular radiotherapy. For the sake of the patients, irradiation methods, which do not provoke any risk of radiation hazards, have to be preserved and applied in practice. Certainly further research and the nosologic nature of hemangiomas is required. A general non-treatment of hemangiomas is refused.

  5. Assessment of planning target volume margins for intensity-modulated radiotherapy of the prostate gland: role of daily inter- and intrafraction motion.

    Science.gov (United States)

    Tanyi, James A; He, Tongming; Summers, Paige A; Mburu, Ruth G; Kato, Catherine M; Rhodes, Stephen M; Hung, Arthur Y; Fuss, Martin

    2010-12-01

    To determine planning target volume margins for prostate intensity-modulated radiotherapy based on inter- and intrafraction motion using four daily localization techniques: three-point skin mark alignment, volumetric imaging with bony landmark registration, volumetric imaging with implanted fiducial marker registration, and implanted electromagnetic transponders (beacons) detection. Fourteen patients who underwent definitive intensity-modulated radiotherapy for prostate cancer formed the basis of this study. Each patient was implanted with three electromagnetic transponders and underwent a course of 39 treatment fractions. Daily localization was based on three-point skin mark alignment followed by transponder detection and patient repositioning. Transponder positioning was verified by volumetric imaging with cone-beam computed tomography of the pelvis. Relative motion between the prostate gland and bony anatomy was quantified by offline analyses of daily cone-beam computed tomography. Intratreatment organ motion was monitored continuously by the Calypso® System for quantification of intrafraction setup error. As expected, setup error (that is, inter- plus intrafraction motion, unless otherwise stated) was largest with skin mark alignment, requiring margins of 7.5 mm, 11.4 mm, and 16.3 mm, in the lateral (LR), longitudinal (SI), and vertical (AP) directions, respectively. Margin requirements accounting for intrafraction motion were smallest for transponder detection localization techniques, requiring margins of 1.4 mm (LR), 2.6 mm (SI), and 2.3 mm (AP). Bony anatomy alignment required 2.1 mm (LR), 9.4 mm (SI), and 10.5 mm (AP), whereas image-guided marker alignment required 2.8 mm (LR), 3.7 mm (SI), and 3.2 mm (AP). No marker migration was observed in the cohort. Clinically feasible, rapid, and reliable tools such as the electromagnetic transponder detection system for pretreatment target localization and, subsequently, intratreatment target location monitoring

  6. Radiation-induced Liver Injury after 3D-conformal Radiotherapy for Hepatocellular Carcinoma: Quantitative Assessment Using Gd-EOB-DTPA-enhanced MRI.

    Science.gov (United States)

    Fukugawa, Yoshiyuki; Namimoto, Tomohiro; Toya, Ryo; Saito, Tetsuo; Yuki, Hideaki; Matsuyama, Tomohiko; Ikeda, Osamu; Yamashita, Yasuyuki; Oya, Natsuo

    2017-02-01

    Focal liver reaction (FLR) appears in the hepatobiliary-phase images of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI) following radiotherapy (RT). We investigated the threshold dose (TD) for FLR development in 13 patients with hepatocellular carcinoma (HCC) who underwent three-dimensional conformal radiotherapy (3D-CRT) with 45 Gy in 15 fractions. FLR volumes (FLRVs) were calculated based on planning CT images by referring to fused hepatobiliary- phase images. We also calculated the TD and the irradiated volumes (IVs) of the liver parenchyma at a given dose of every 5 Gy (IVdose) based on a dose-volume histogram (DVH). The median TD was 35.2 Gy. The median IV20, IV25, IV30, IV35, IV40, and IV45 values were 371.1, 274.8, 233.4, 188.6, 145.8, and 31.0 ml, respectively. The median FLRV was 144.9 ml. There was a significant difference between the FLRV and IV20, IV25, and IV45 (p<0.05), but no significant differences between the FLRV and IV30, IV35, or IV40. These results suggest that the threshold dose of the FLR is approx. 35 Gy in HCC patients who undergo 3D-CRT in 15 fractions. The percentage of the whole liver volume receiving a dose of more than 30-40 Gy (V30-40) is a potential candidate optimal DVH parameter for this fractionation schedule.

  7. An assessment of quality of life for early phase after adjuvant radiotherapy in breast cancer survivors: a Korean multicenter survey (KROG 14-09).

    Science.gov (United States)

    Rim, Chai Hong; Ahn, Sung-Ja; Kim, Jin Hee; Yoon, Won Sup; Chun, Mison; Yang, Dae Sik; Lee, Jong-Hoon; Kim, Kyubo; Kong, Moonkyoo; Kim, Suzy; Kim, Juree; Park, Kyung Ran; Shin, Young-Joo; Ma, Sun Young; Jeong, Bae-Kwon; Kim, Su Ssan; Kim, Yong Bae; Lee, Dong Soo; Cha, Jaehyung

    2017-05-10

    Quality of life (QoL) has become a major concern as the survival time of breast cancer increases. We investigated the changes in QoL through comprehensive categorical analysis, for the first three years after breast cancer treatment including radiotherapy. A total of 1156 patients were enrolled from 17 institutions. All survivors were grouped according to a surveillance period of 9-15 months (first year), 21-27 months (second year), and 33-39 months (third year) from the end of radiotherapy. The 5-dimensional questionnaire by the EuroQol group (EQ-5D) and the EORTC Quality of Life Questionnaire; breast cancer specific module (QLQ-BR23) were checked by self-administrated method. First, second and third year groups comprised 51.0, 28.9, and 21.0%. In EQ-5D-3 L (3-Likert scale) analysis, pain/discomfort and anxiety/depression categories showed lower QoL. In multivariate analyses of EQ-5D-VAS (visual-analogue scale), categories of pain/discomfort and self-care were improved with time; axillary dissection was a significant clinical factor deteriorates pain/discomfort, self-care and usual activities. In QLQ-BR23 analysis, the lowest scored category was sexual activity, followed by sexual enjoyment, future perspective, and hair loss, and the best scored category was breast symptoms. In multivariate analyses, arm symptoms, breast symptoms and body image were improved with time. Categories of pain/discomfort and self-care in EQ-5D-VAS, arm/breast symptoms and body image in QLQ-BR23 were improved, while categories of anxiety/depression and future perspective BR23 were not, suggesting necessity of psychosocial support. This research provides comprehensive information on the categorical aspects of QoL and changes during early follow-up after breast cancer treatment.

  8. Post-Irradiation Bladder Syndrome After Radiotherapy of Malignant Neoplasm of Small Pelvis Organs: An Observational, Non-Interventional Clinical Study Assessing VESIcare®/Solifenacin Treatment Results.

    Science.gov (United States)

    Jaszczyński, Janusz; Kojs, Zbigniew; Stelmach, Andrzej; Wohadło, Łukasz; Łuczyńska, Elzbieta; Heinze, Sylwia; Rys, Janusz; Jakubowicz, Jerzy; Chłosta, Piotr

    2016-07-30

    BACKGROUND Radiotherapy is explicitly indicated as one of the excluding factors in diagnosing overactive bladder syndrome (OAB). Nevertheless, symptoms of OAB such as urgent episodes, incontinence, pollakiuria, and nocturia, which are consequences of irradiation, led us to test the effectiveness of VESIcare®/Solifenacin in patients demonstrating these symptoms after radiation therapy of small pelvis organs due to malignant neoplasm. MATERIAL AND METHODS We conducted an observatory clinical study including 300 consecutive patients with symptoms of post-irradiation bladder; 271 of those patients completed the study. The observation time was 6 months and consisted of 3 consecutive visits taking place at 12-week intervals. We used VESIcare® at a dose of 5 mg a day. Every sixth patient was examined urodynamically at the beginning and at the end of the observation period, with an inflow speed of 50 ml/s. RESULTS We noticed improvement and decline in the average number of episodes a day in the following parameters: number of micturitions a day (-36%, P<0.01), nocturia (-50%, P<0.01), urgent episodes (-41%, P<0.03), and episodes of incontinence (-43%, P<0.01). The patients' quality of life improved. The average maximal cystometric volume increased by 34 ml (21%, p<0.01), average bladder volume of "first desire" increased by 42 ml (49%, P<0.01), and average detrusor muscle pressure at maximal cystometric volume diminished by 9 cmH2O (-36%, P<0.03). CONCLUSIONS The substance is well-tolerated. Solifenacin administered long-term to patients with symptoms of OAB after radiotherapy of a malignant neoplasm of the small pelvis organs has a daily impact in decreasing number of urgent episodes, incontinence, pollakiuria, and nocturia.

  9. Postoperative radiotherapy for ependymoma

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Hong; Ahn, Seung Do; Park, Jin Hong [Dept. of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); and others

    2012-12-15

    To evaluated the patterns of failure, survival rate, treatment-related toxicity and prognostic factors in postoperative radiotherapy of patients with ependymoma. Thirty patients who underwent surgery and postoperative radiotherapy for ependymoma between the period of June 1994 and June 2008 were reviewed retrospectively. The age of patients ranged from 21 months to 66 years (median, 19 years). Seventeen patients had grade II ependymoma, and 13 had grade III anaplastic ependymoma according to the World Health Organization grading system. The postoperative irradiation was performed with 4 or 6 MV photon beam with median dose of 52.8 Gy (range, 45 to 63 Gy), and radiation field including 2 cm beyond the preoperative tumor volume. Median follow-up period was 51 months (range, 12 to 172 months). Fourteen out of 30 (46.7%) patients experienced recurrence, and 12 of those died. Among those 14 patients who experienced recurrence, 11 were in-field and 3 were out-of-field recurrence. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 66.7% and 56.1%, respectively. On univariate analysis, tumor grade was a statistically significant prognostic factor for OS and PFS. There were two complications after surgery and postoperative radiotherapy, including short stature and facial palsy on the left side. We observed good survival rates, and histologic grade was a prognostic factor affecting the OS and PFS. Almost all recurrence occurred in primary tumor site, thus we suggest further evaluation on intensity-modulated radiotherapy or stereotatic radiosurgery for high-risk patients such as who have anaplastic ependymoma.

  10. Endorectal MRI assessment of local relapse after surgery for prostate cancer: A model to define treatment field guidelines for adjuvant radiotherapy in patients at high risk for local failure.

    Science.gov (United States)

    Miralbell, Raymond; Vees, Hansjörg; Lozano, Joan; Khan, Haleem; Mollà, Meritxell; Hidalgo, Alberto; Linero, Dolors; Rouzaud, Michel

    2007-02-01

    To assess the role of endorectal magnetic resonance imaging (MRI) in defining local relapse after radical prostatectomy for prostate cancer to help to reassess the clinical target volume (CTV) for adjuvant postprostatectomy radiotherapy. Sixty patients undergoing an endorectal MRI before salvage radiotherapy were selected. Spatial coordinates of the relapses were assessed using two reference points: the inferior border of the pubic symphysis (point 1) and the urethro-vesical anastomosis (point 2). Every lesion on MRI was delineated on the planning computed tomography and center of mass coordinates were plotted in two separate diagrams (along the x, y, and z axes) with the urethro-vesical anastomosis as the coordinate origin. An "ideal" CTV was constructed, centered at a point defined by the mathematical means of each of the three coordinates with dimensions defined as twice 2 standard deviations in each of the three axes. The dosimetric impact of the new CTV definition was evaluated in six adjuvantly treated patients. The ideal CTV center of mass was located at coordinates 0 (x), -5 (y), and -3 (z) mm with SDs of 6 (x), 6 (y), and 9 (z) mm, respectively. The CTV size was 24 (x) x 24 (y) x 36 (z) mm. Significant rectal sparing was observed with the new CTV. A CTV with an approximately cylindrical shape (approximately 4 x 3 cm) centered 5 mm posterior and 3 mm inferior to the urethro-vesical anastomosis was defined. Such CTV may reduce the irradiation of normal nontarget tissue in the pelvis potentially improving treatment tolerance.

  11. First trimester two- and four-dimensional cardiac scan: intra- and interobserver agreement, comparison between methods and benefits of color Doppler technique.

    Science.gov (United States)

    Tudorache, S; Cara, M; Iliescu, D G; Novac, L; Cernea, N

    2013-12-01

    To evaluate intra- and interobserver agreement for first-trimester fetal cardiac structural assessment, using two-dimensional (2D) ultrasound (2D-US) and 4D-US (4D spatiotemporal image correlation (STIC) technology), to compare the methods and to assess the advantages of adding color Doppler to each technique. Digital videoclips (B-mode and color Doppler) and 4D-STIC volumes (gray-scale and color Doppler) from 632 pregnancies with normal fetal hearts were acquired and stored at the time of detailed first-trimester ultrasound examination. Later analysis on a randomized sample of 100 cases was performed, targeting 11 cardiac structures and features. We compared visualization of fetal heart parameters using 2D-US vs 4D-US and gray-scale vs color Doppler imaging. STIC volumes were considered satisfactory (adequate visualization of at least 8/11 parameters) in 78% of cases and 2D-US acquisitions in 89% of cases. The intra- and interobserver agreement was good for both 2D and 4D methods (kappa > 0.6), and the percentage overall agreement was very high using both methods (95%). 2D- and 4D-US identification of the fetal cardiac parameters did not differ significantly. The differences between gray-scale and color Doppler imaging were statistically significant in identifying similar key cardiac parameters, for both 2D- and 4D-US (P parameters are feasible and repeatable within and between observers. Color Doppler adds valuable information to both methods. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.

  12. Four-dimensional measurement of the displacement of metal clips or postoperative surgical staples during 320-multislice computed tomography scanning of gastric cancer

    Directory of Open Access Journals (Sweden)

    Yamashita Hideomi

    2012-08-01

    Full Text Available Abstract Purpose To investigate the respiratory motion of metal clips or surgical staples placed in the gastric wall for planning of radiation therapy in gastric cancer patients. Methods This study examined 15 metal markers in the gastric walls of 12 patients with gastric cancer treated with external-beam photon RT. Motion assessment was analyzed in 41 respiratory phases covering 20 s acquired with computed tomography (CT in the RT position using 320-multislice CT. The intra-fraction displacement was assessed in the cranio-caudal (CC, antero-posterior (AP, and right-left (RL directions. Results Motion in the CC direction showed a very strong correlation (R2 > 0.7 with the respiratory curve in all 15 markers. The mean (+/− SD intra-fractional gastric motion (maximum range of displacement was 12.5 (+/− 3.4 mm in the CC, 8.3 (+/− 2.2 mm in the AP, and 5.5 (+/− 3.0 mm in the RL direction. No significant differences in magnitude of motion were detected in the following: a among the upper (n = 6, middle (n = 4, and lower (n = 5 stomach regions; b between metal clips (n = 5 and surgical staples (n = 10; and c between full (n = 9 and empty (n = 6 stomachs. Conclusions Motion in primary gastric tumor was evaluated with 320-multislice CT. According to this study, the 95th percentile values from the cumulative distributions of the RL, AP, and CC direction were 6.3 mm, 9.0 mm, and 13.6 mm, respectively.

  13. Radiotherapy of vertebral hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, Kohichi; Hareyama, Masato; Oouchi, Atushi; Sido, Mitsuo; Nagakura, Hisayasu; Tamakawa, Mituharu; Akiba, Hidenari; Morita, Kazuo [Dept. of Radiology, Sapporo Medical Univ., School of Medicine (Japan)

    1997-12-31

    Between 1975 and 1996, 14 patients (11 females, 3 males) with vertebral hemangioma received treatment with radiotherapy. Thirteen patients had a history of back pain or lumbago and 2 patients had neurological symptoms such as sensory impairment or paraplegia. The standard dose administered was 36 Gy in 18 fractions (five treatments per week). In the 13 patients with pain, this was completely or partially relieved. The condition of a man with hypesthesia of the legs deteriorated and a woman with paraplegia who was treated with decompressive laminectomy followed by radiotherapy recovered completely after irradiation. CT scan before irradiation showed thickened trabeculae as small punctate areas of sclerosis in all patients. At MR imaging before irradiation, T2-weighted MR images showed areas of high intensity in all patients and MR images demonstrated lesion enhancement. However, none of the patients who were treated successfully with radiation demonstrated any changes of the affected vertebra in the conventional radiographic films, CT scan or MR imaging, even 5 years after irradiation. Radiological imaging is indispensable for the diagnosis of vertebral hemangiomas but does not appear to be useful for evaluating the effects of radiotherapy. (orig.).

  14. Unintended cardiac irradiation during left-sided breast cancer radiotherapy.

    Science.gov (United States)

    Goody, R B; O'Hare, J; McKenna, K; Dearey, L; Robinson, J; Bell, P; Clarke, J; McAleer, J J A; O'Sullivan, J M; Hanna, G G

    2013-02-01

    Cardiac irradiation during left-sided breast radiotherapy may lead to deleterious cardiac side effects. Using image guided radiotherapy, it is possible to exclude the heart from treatment fields and monitor reproducibility of virtual simulation (VS) fields at treatment delivery using electronic portal imaging (EPI). Retrospectively, we evaluate the incidence of cardiac irradiation at VS and subsequent unintended cardiac irradiation during treatment. Patients receiving left-sided radiotherapy to the breast or chest wall, treated with a glancing photon field technique during a four-month period, were included. VS images and EPIs during radiotherapy delivery were visually assessed. The presence of any portion of the heart within the treatment field at VS or during treatment was recorded. Central lung distance and maximum heart distance were recorded. Of 128 patients, 45 (35.1%) had any portion of the heart within the planned treatment field. Of these, inclusion of the heart was clinically unavoidable in 25 (55.6%). Of those with no heart included in the treatment fields at VS, 41 (49.4%) had presence of the heart as assessed on EPI during treatment. Unintended cardiac irradiation during left-sided breast radiotherapy treatment occurs in a sizeable proportion of patients. Despite the use of three-dimensional computed tomography simulation and cardiac shielding, sizeable proportions of patients receiving left-sided breast cancer radiotherapy have unintended cardiac irradiation.

  15. Dynamic MRI analysis of tumor and organ motion during rest and deglutition and margin assessment for radiotherapy of head-and-neck cancer.

    Science.gov (United States)

    Bradley, Julie A; Paulson, Eric S; Ahunbay, Ergun; Schultz, Christopher; Li, X Allen; Wang, Dian

    2011-12-01

    To quantify swallowing frequency and tumor and normal structure displacements during deglutition using dynamic magnetic resonance imaging (MRI) and to determine planning target volume (PTV) margins to account for resting and deglutition-induced displacements in patients with head-and-neck cancer (HNC). Twenty-two patients with HNC were imaged in the treatment position using dynamic MRI. Sagittal images were acquired. Two-dimensional displacement was analyzed using contours of normal structures and GTV drawn for one swallowing event. Deglutition-induced displacements were quantified based on position change during deglutition relative to preswallow structure location for anterior (A), posterior (P), superior (S), and inferior (I) directions. Additional long-time MRI series were obtained from a subset of 11 patients while they were resting in order to determine swallowing frequency and duration. PTV margins to account for setup error, frequency and duration of deglutition, and resting and deglutition-induced GTV motion were calculated. Mean maximum resting displacements ranged from 1.5 to 3.1 mm for combined GTV subsites. Mean maximum swallowing GTV displacement for combined subsites ranged from 4.0 to 11.6 mm. Swallowing was nonperiodic, with a frequency ranging from 0 to 19 swallows over 12.8 min and mean swallow duration of 3.5 s. Based on the average swallowing characteristics in this cohort, the average PTV margins to account for setup error and tumor motion are estimated to be 4.7 mm anteriorly, 4.2 mm posteriorly, 4.7 mm inferiorly, and 6.0 mm superiorly. The measurable mean maximum resting displacement for the GTV indicates that tumor motion occurs even when the patient is not swallowing. Nonuniform margins should be used as a standard PTV margin that accounts for setup error and tumor motion in radiotherapy of HNC unless adaptive radiotherapy with respect to intrafraction tumor motion is performed. The PTV margin can be individualized to a single patient

  16. Ileocolic free flap reconstruction, concomitant chemotherapy and radiotherapy and assessment of speech and swallowing function during management of advanced cancer of the larynx and hypopharynx: preliminary report.

    Science.gov (United States)

    Leu, Yi-Shing; Hsiao, Hung-Tao; Chang, Yuan-Ching; Yang, Cheng-Chien; Lee, Jehn-Chuan; Chen, Yu-Jen; Chang, Yi-Fang

    2005-06-01

    The new technique of ileocolic free flap reconstruction provides a better quality of life in terms of swallowing and speech for patients who have undergone laryngopharyngectomy with concomitant chemotherapy and radiotherapy (CCRT). To compare and contrast the swallowing and speech outcomes of patients who underwent total laryngopharyngectomy with ileocolic free flap reconstruction and to analyze the survival rate after surgery and CCRT. This was a follow-up study of 12 patients with advanced (stages III, IVA and IVB) laryngeal and hypopharyngeal cancer who underwent major surgery, CCRT (with one exception) and ileocolic free flap reconstruction. All patients were able to tolerate single-stage combined management comprising total laryngopharyngectomy with or without radical neck dissection plus ileocolic free flap reconstruction and postoperative CCRT (with one exception), without immediate morbidity or mortality. Eleven patients were diagnosed with hypopharyngeal cancer and one with laryngeal cancer. The mean interval between surgery and CCRT was 34.1 days. The mean follow-up period was 16.5 months. Four patients died during the follow-up period as a result of local recurrence (n=2), distant metastasis (n=1) and suicide (n=1). One patient was alive with disease despite neck recurrence.

  17. Radiotherapy for eyelid cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saika, Kazumi [Yokohama City Univ. (Japan). School of Medicine

    2001-05-01

    Some studies on radiotherapy for eyelid cancer have been reported, but the optimal radiation doses for different histological types and tumor sizes have not been detailed. So I studied the optimal radiation doses in radiotherapy for eyelid cancer. The patients were fourteen and histological diagnoses were made on the basis of biopsies or surgery before radiotherapy. Surgical cut margins were positive in 10 cases. In 5 of these cases, tumors were visible. There were 9 sebaceous adenocarcinomas (SAC), 4 squamous cell carcinomas (SCC), and 1 basal cell carcinoma (BCC). In 13 of 14 cases, radiation was applied to eyelids in which tumor-surgical cut margin distances were 3 mm or less. The eyeballs were covered with lead or tungsten shields, and the eyelids were irradiated with a total dose of 50 to 66.6 Gy. In 5 cases, radiation was applied prophylactically for ipsilateral pre-auricle lymph node areas. 11 of 13 cases were locally controlled. I gave greater radiation doses for SAC than for SCC or BCC. I also gave greater doses for in visible tumors than for invisible ones. In the acute phase dermatitis, inflammation of the cornea, conjunctivitis, etc. occurred but they were mild. Later reactions were decreased cilia, dry eye, inflammation of cornea, conjunctivitis, discomfort of the scar, etc. Cataracts were also seen, but they were of senile origen. Because 81.8% of the tumors were controlled, this radiation method was useful with salvage therapies to select an optimal radiation dose according to the differences among histological types and tumor sizes. 60% of visible tumors were also controlled so I think that radical therapy using radiation alone is possible. (author)

  18. [Radiotherapy of bladder cancer].

    Science.gov (United States)

    Riou, O; Chauvet, B; Lagrange, J-L; Martin, P; Llacer Moscardo, C; Charissoux, M; Lauche, O; Aillères, N; Fenoglietto, P; Azria, D

    2016-09-01

    Surgery (radical cystectomy) is the standard treatment of muscle-invasive bladder cancer. Radiochemotherapy has risen as an alternative treatment option to surgery as part as organ-sparing combined modality treatment or for patients unfit for surgery. Radiochemotherapy achieves 5-year bladder intact survival of 40 to 65% and 5-year overall survival of 40 to 50% with excellent quality of life. This article introduces the French recommendations for radiotherapy of bladder cancer: indications, exams, technique, dosimetry, delivery and image guidance. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  19. Hyperfractionated or accelerated radiotherapy in head and neck cancer: a meta-analysis

    DEFF Research Database (Denmark)

    Bourhis, J.; Overgaard, Jens; Audry, H.

    2006-01-01

    BACKGROUND: Several trials have studied the role of unconventional fractionated radiotherapy in head and neck squamous cell carcinoma, but the effect of such treatment on survival is not clear. The aim of this meta-analysis was to assess whether this type of radiotherapy could improve survival....... METHODS: Randomised trials comparing conventional radiotherapy with hyperfractionated or accelerated radiotherapy, or both, in patients with non-metastatic HNSCC were identified and updated individual patient data were obtained. Overall survival was the main endpoint. Trials were grouped in three pre...... year olds; test for trends p=0.007). INTERPRETATION: Altered fractionated radiotherapy improves survival in patients with head and neck squamous cell carcinoma. Comparison of the different types of altered radiotherapy suggests that hyperfractionation has the greatest benefit....

  20. Radiotherapy Breast Boost With Reduced Whole-Breast Dose Is Associated With Improved Cosmesis: The Results of a Comprehensive Assessment From the St. George and Wollongong Randomized Breast Boost Trial

    Energy Technology Data Exchange (ETDEWEB)

    Hau, Eric, E-mail: helloerico@yahoo.com [Cancer Care Centre, St. George Hospital, Kogarah, Sydney (Australia); Browne, Lois H.; Khanna, Sam; Cail, Stacy; Cert, Grad; Chin, Yaw; Clark, Catherine; Inder, Stephanie; Szwajcer, Alison; Graham, Peter H. [Cancer Care Centre, St. George Hospital, Kogarah, Sydney (Australia)

    2012-02-01

    Purpose: To evaluate comprehensively the effect of a radiotherapy boost on breast cosmetic outcomes after 5 years in patients treated with breast-conserving surgery. Methods: The St. George and Wollongong trial (NCT00138814) randomized 688 patients with histologically proven Tis-2, N 0-1, M0 carcinoma to the control arm of 50 Gy in 25 fractions (342 patients) and the boost arm of 45 Gy in 25 fractions to the whole breast followed by a 16 Gy in 8 fraction electron boost (346 patients). Five-year cosmetic outcomes were assessed by a panel subjectively in 385 patients and objectively using pBRA (relative breast retraction assessment). A subset of patients also had absolute BRA measurements. Clinician assessment and patient self-assessment of overall cosmetic and specific items as well as computer BCCT.core analysis were also performed. Results: The boost arm had improved cosmetic overall outcomes as scored by the panel and BCCT.core software with 79% (p = 0.016) and 81% (p = 0.004) excellent/good cosmesis respectively compared with 68% in no-boost arm. The boost arm also had lower pBRA and BRA values with a mean difference of 0.60 and 1.82 mm, respectively, but was not statistically significant. There was a very high proportion of overall excellent/good cosmetic outcome in 95% and 93% in the boost and no-boost arms using patient self-assessment. However, no difference in overall and specific items scored by clinician assessment and patient self-assessment was found. Conclusion: The results show the negative cosmetic effect of a 16-Gy boost is offset by a lower whole-breast dose of 45 Gy.

  1. Evaluation of kidney motion with and without a pneumatic abdominal compression belt: Considerations for stereotactic radiotherapy.

    Science.gov (United States)

    West, Kimberley; Russo, Majella; Brown, Elizabeth; Barry, Tamara; Hargrave, Cathy; Pryor, David

    2017-10-09

    The optimal delivery of stereotactic radiotherapy for kidney tumours requires an effective motion management strategy. This study assessed the effectiveness of a pneumatic abdominal compression belt in reducing kidney motion during free breathing. Thirteen patients, with four-dimensional computed tomography (4DCT) of the abdomen in free breathing with and without a pneumatic abdominal compression belt, were retrospectively reviewed. Points of Interest (POI) were placed on each kidney to determine the greatest magnitude of displacement in all directions. Without compression, all patients had >5.0 mm motion in the craniocaudal (CC) direction in at least one kidney. Median CC excursion of the left superior pole was reduced with compression from 8.0 mm (range 2.0 mm-18.0 mm) to 4.0 mm (range 2.0 mm-10.0 mm, P = 0.047) and right superior pole from 10.0 mm (range 4.0 mm-16.0 mm) to 6.0 mm (range 2.0 mm-10.0 mm, P=value 0.051). A benefit was less evident for the left and right inferior poles with median CC excursion of 6.0 mm versus 4.0 mm and 5.0 mm versus 4.0 mm without and with compression, respectively. Median displacement in the anteroposterior direction (≤3.2 mm) and lateral directions (≤1.3 mm) was similar for left and right kidneys and not significantly altered by compression. Overall, seven patients had kidney motion reduced by >5.0 mm with two reduced by 10.0 mm. A pneumatic abdominal compression belt reduced kidney motion by >5.0 mm in seven of thirteen patients. The relative benefit is patient and location specific and should be assessed on an individual basis. © 2017 The Royal Australian and New Zealand College of Radiologists.

  2. Respiratory gated radiotherapy-pretreatment patient specific quality assurance

    Directory of Open Access Journals (Sweden)

    Rajesh Thiyagarajan

    2016-01-01

    Full Text Available Organ motions during inter-fraction and intra-fraction radiotherapy introduce errors in dose delivery, irradiating excess of normal tissue, and missing target volume. Lung and heart involuntary motions cause above inaccuracies and gated dose delivery try to overcome above effects. Present work attempts a novel method to verify dynamic dose delivery using a four-dimensional (4D phantom. Three patients with mobile target are coached to maintain regular and reproducible breathing pattern. Appropriate intensity projection image set generated from 4D-computed tomography (4D-CT is used for target delineation. Intensity modulated radiotherapy plans were generated on selected phase using CT simulator (Siemens AG, Germany in conjunction with "Real-time position management" (Varian, USA to acquire 4D-CT images. Verification plans were generated for both ion chamber and Gafchromic (EBT film image sets. Gated verification plans were delivered on the phantom moving with patient respiratory pattern. We developed a MATLAB-based software to generate maximum intensity projection, minimum intensity projections, and average intensity projections, also a program to convert patient breathing pattern to phantom compatible format. Dynamic thorax quality assurance (QA phantom (Computerized Imaging Reference Systems type is used to perform the patient specific QA, which holds an ion chamber and film to measure delivered radiation intensity. Exposed EBT films are analyzed and compared with treatment planning system calculated dose. The ion chamber measured dose shows good agreement with planned dose within ± 0.5% (0.203 ± 0.57%. Gamma value evaluated from EBT film shows passing rates 92–99% (96.63 ± 3.84% for 3% dose and 3 mm distance criteria. Respiratory gated treatment delivery accuracy is found to be within clinically acceptable level.

  3. Impact of pelvic radiotherapy on female sexuality.

    Science.gov (United States)

    Rodrigues, Ana Cláudia; Teixeira, Rubina; Teixeira, Tânia; Conde, Sofia; Soares, Paula; Torgal, Isabel

    2012-02-01

    To assess physical and psychological morbidity, sexual functioning and social and relationship satisfaction among women treated with pelvic radiotherapy. Observational (case-control) study of 199 women: 98 submitted to pelvic radiotherapy for the treatment of uterine, rectal or anal cancers and 101 without a personal history of cancer and similar socio-demographic variables. These completed a socio-demographic and clinical questionnaire, and validated measures of psychological health (DASS: Lovibond and Lovibond in Behav Res Ther 33:353-343, 1995), sexual function (FSFI: Rosen et al. in J Sex Marital Ther 26:191-208, 2007), social support (ESSS: Ribeiro in Analise Psicologica 3:547-558, 1999) and relationship satisfaction (IMS: Hudson in The WALMYR assessment scales scoring manual 1992). Women submitted to pelvic irradiation reported a higher rate of adverse physical symptoms in the last month: fatigue 59 versus 25% (p radiotherapy patients, but only reach statistical significance for the stress parameter (6.1 vs. 4.0, p = 0.012). Also these women reported lower scores of satisfaction with social support (57.2 vs. 62.2, p = 0.005) and sexual function (8.5 vs. 13.5, p = 0.049). No statistically significant differences occurred between the two groups regarding scores of relationship satisfaction (20.8 vs. 19.9, p = n.s.). Our results suggested that pelvic radiotherapy had a negative impact on female sexuality. Thus, interventions that would help to reduce this impact need to be designed and integrated into routine clinical practice.

  4. Role of palliative radiotherapy in brain metastases

    Directory of Open Access Journals (Sweden)

    Ramesh S Bilimagga

    2009-01-01

    Full Text Available Background: Brain metastases are a common manifestation of systemic cancer and exceed primary brain tumors in number and are a significant cause of neurologic problems. They affect 20-40% of all cancer patients. Aggressive management of brain metastases is effective in both symptom palliation and prolonging the life. Radiotherapy has a major role to play in the management of brain metastases. AIM: The aim of the study was to know the outcome of palliative radiotherapy in symptomatic brain metastases in terms of improvement in their performance status. Materials and Methods: This is a retrospective study of 63 patients diagnosed to have brain metastases and treated with palliative whole brain radiotherapy to a dose of 30 Gy in 10 fractions over two weeks between June 1998 and June 2007. Diagnosis was done in most of the cases with computed tomography scan and in a few with magnetic resonance imaging. Improvement in presenting symptoms has been assessed in terms of improvement in their performance status by using the ECOG scale. Results: Fifty-four patients completed the planned treatment. Eight patients received concurrent Temozolamide; 88% of patients had symptom relief at one month follow-up; 39/54 patients had a follow-up of just one to three months. Hence survival could not be assessed in this study. Conclusion: External beam radiotherapy in the dose of 30 Gy over two weeks achieved good palliation in terms improvement in their performance status in 88% of patients. Addition of concurrent and adjuvant Timozolamide may improve the results.

  5. Four-dimensional CDT with toroidal topology

    Directory of Open Access Journals (Sweden)

    J. Ambjørn

    2017-09-01

    Full Text Available 3+1 dimensional Causal Dynamical Triangulations (CDT describe a quantum theory of fluctuating geometries without the introduction of a background geometry. If the topology of space is constrained to be that of a three-dimensional torus we show that the system will fluctuate around a dynamically formed background geometry which can be understood from a simple minisuperspace action which contains both a classical part and a quantum part. We determine this action by integrating out degrees of freedom in the full model, as well as by transfer matrix methods.

  6. A Four-Dimensional Product Innovativeness Typology

    DEFF Research Database (Denmark)

    Rosenø, Axel

    2005-01-01

    Product innovativeness is a key moderating variable for the study of innovationmanagement (Song & Montoya-Weiss 1998, p. 124). For this reason, some empiricalstudies of innovation management examine new product processes, critical successfactors, and market learning practices for incremental versus......) typology with four newproduct types; Leonard-Barton's (1995) five product types; and Veryzer's (1998a)four types in a two-by-two matrix.Interestingly, these two meta-perspectives on product innovativeness (i.e. 1. new tothe market and/or new to the company and 2. technological and/or marketnewness...... discontinuous newproduct projects (Song & Montoya-Weiss 1998; Atuahene-Gima 1995; Veryzer 1998a;Lynn et al. 1996; O'Connor 1998; Rice et al. 1998). By looking at both these types ofnew product development projects, empirical observations are likely to be morerealistic than those of studies that do...

  7. An instrument dedicated for modelling of pulmonary radiotherapy.

    Science.gov (United States)

    Niezink, Anne G H; Dollekamp, Nienke J; Elzinga, Harriet J; Borger, Denise; Boer, Eduard J H; Ubbels, Jan F; Woltman-van Iersel, Marleen; van der Leest, Annija H D; Beijert, Max; Groen, Harry J M; Kraan, Jan; Hiltermann, Thijo J N; van der Wekken, Anthonie J; van Putten, John W G; Rutgers, Steven R; Pieterman, Remge M; de Hosson, Sander M; Roenhorst, Anke W J; Langendijk, Johannes A; Widder, Joachim

    2015-04-01

    Radiotherapy plays a pivotal role in lung cancer treatment. Selection of patients for new (radio)therapeutic options aiming at improving outcomes requires reliable and validated prediction models. We present the implementation of a prospective platform for evaluation and development of lung radiotherapy (proPED-LUNG) as an instrument enabling multidimensional predictive modelling. ProPED-LUNG was designed to comprise relevant baseline and follow up data of patients receiving pulmonary radiotherapy with curative intent. Patient characteristics, diagnostic and staging information, treatment parameters including full dose-volume-histograms, tumour control, survival, and toxicity are scored. Besides physician-rated data, a range of patient-rated data regarding symptoms and health-related quality-of-life are collected. After 18 months of accrual, 315 patients have been included (accrual rate, 18 per month). Of the first hundred patients included, 70 received conformal (chemo)radiotherapy and 30 underwent stereotactic radiotherapy. Compliance at 3 and 6 months follow-up was 96-100% for patient-rated, and 81-94% for physician-rated assessments. For data collection, 0.4 FTE were allocated in a 183 FTE department (0.2%). ProPED-LUNG is feasible with high compliance rates and yields a large amount of high quality prospective disease-related, treatment-related, patient- and physician-rated data which can be used to evaluate new developments in pulmonary radiotherapy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Factors associated with refusal of radiotherapy among oral cancer patients

    Directory of Open Access Journals (Sweden)

    Agaku IT

    2013-04-01

    Full Text Available Background: Surgery is commonly favored in the management of oral cancer but radiotherapy may be essential because of the size or location of the tumor. Refusal of radiotherapy by patients is an important issue, which must be taken into consideration during treatment planning. This study assessed prevalence and correlates of radiotherapy refusal among oral cancer patients. Methods: Data was analyzed for 47, 174 oral cancer cases in the Surveillance, Epidemiology and End Results (SEER database during 1988–2008. Point estimates were calculated overall and by selected socio-demographic and clinical characteristics. A multivariate logistic regression model was fitted to determine predictors of radiotherapy refusal. Results: The overall prevalence of refusal of radiotherapy was 2.31%. Factors associated with increased likelihood of refusal of radiotherapy included age ± 45 years (adjusted odds ratio, aOR=2.48; P=0.031; gingival/floor of mouth tumors (aOR=1.32; P=0.010; receipt of surgery (aOR=1.21; P=0.04. Conversely, protective factors included being married (aOR=0.59; P<0.001; non-Hispanic blacks (aOR=0.53; P=0.001; involvement of paired structures (aOR=0.61; P<0.001 as well as multiple tumors (aOR=0.75; P=0.021. Sex was not a significant predictor on multivariate analysis. Conclusion: Prevalence of refusal of radiotherapy among oral cancer patients is relatively low and is significantly associated with age, marital status, as well as location, extent and severity of disease. Clinicians may anticipate patients likely to refuse radiotherapy and develop patient-tailored counseling considering the benefits and risks of proposed treatment. Final treatment decision must however take into consideration the wishes of the fully informed patient.

  9. Proton minibeam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Girst, Stefanie

    2016-03-08

    The risk of developing adverse side effects in the normal tissue after radiotherapy is often limiting for the dose that can be applied to the tumor. Proton minibeam radiotherapy, a spatially fractionated radiotherapy method using sub-millimeter proton beams, similar to grid therapy or microbeam radiation radiotherapy (MRT) using X-rays, has recently been invented at the ion microprobe SNAKE in Munich. The aim of this new concept is to minimize normal tissue injuries in the entrance channel and especially in the skin by irradiating only a small percentage of the cells in the total irradiation field, while maintaining tumor control via a homogeneous dose in the tumor, just like in conventional broad beam radiotherapy. This can be achieved by optimizing minibeam sizes and distances according to the prevailing tumor size and depth such that after widening of the minibeams due to proton interactions in the tissue, the overlapping minibeams produce a homogeneous dose distribution throughout the tumor. The aim of this work was to elucidate the prospects of minibeam radiation therapy compared to conventional homogeneous broad beam radiotherapy in theory and in experimental studies at the ion microprobe SNAKE. Treatment plans for model tumors of different sizes and depths were created using the planning software LAPCERR, to elaborate suitable minibeam sizes and distances for the individual tumors. Radiotherapy-relevant inter-beam distances required to obtain a homogeneous dose in the target volume were found to be in the millimeter range. First experiments using proton minibeams of only 10 μm and 50 μm size (termed microchannels in the corresponding publication Zlobinskaya et al. 2013) and therapy-conform larger dimensions of 100 μm and 180 μm were performed in the artificial human in-vitro skin model EpiDermFT trademark (MatTek). The corresponding inter-beam distances were 500 μm, 1mm and 1.8 mm, respectively, leading to irradiation of only a few percent of the cells

  10. Brainwave for radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chalmers, Matthew

    2003-11-01

    The award of this year's Nobel Prize in Physiology or Medicine for the development of magnetic resonance imaging (MRI) highlights the central role played by physics in medical imaging. Some 30 years after MRI produced its first 'slices' through the human body, researchers are now combining advanced versions of the technique with radiotherapy to improve the treatment of brain tumours. Roberto Garcia-Alvarez, Andy Beavis and Gary Liney at the University of Hull in the UK have developed a novel approach that combines functional MRI (fMRI) and intensity- modulated radiation therapy (IMRT). Their technique significantly reduces the need to expose certain areas of the brain - such as those responsible for motor function - to radiation during treatment, and could help preserve the quality of life of cancer patients (J. Radiotherapy in Practice 3 55). In the November issue of Physics World Matthew Chalmers describes how by combining imaging techniques and radiation therapy leads to safer targeting of tumours. (U.K.)

  11. Does Motion Assessment With 4-Dimensional Computed Tomographic Imaging for Non–Small Cell Lung Cancer Radiotherapy Improve Target Volume Coverage?

    Directory of Open Access Journals (Sweden)

    Naseer Ahmed

    2017-03-01

    Full Text Available Introduction: Modern radiotherapy with 4-dimensional computed tomographic (4D-CT image acquisition for non–small cell lung cancer (NSCLC captures respiratory-mediated tumor motion to provide more accurate target delineation. This study compares conventional 3-dimensional (3D conformal radiotherapy (3DCRT plans generated with standard helical free-breathing CT (FBCT with plans generated on 4D-CT contoured volumes to determine whether target volume coverage is affected. Materials and methods: Fifteen patients with stage I to IV NSCLC were enrolled in the study. Free-breathing CT and 4D-CT data sets were acquired at the same simulation session and with the same immobilization. Gross tumor volume (GTV for primary and/or nodal disease was contoured on FBCT (GTV_3D. The 3DCRT plans were obtained, and the patients were treated according to our institution’s standard protocol using FBCT imaging. Gross tumor volume was contoured on 4D-CT for primary and/or nodal disease on all 10 respiratory phases and merged to create internal gross tumor volume (IGTV_4D. Clinical target volume margin was 5 mm in both plans, whereas planning tumor volume (PTV expansion was 1 cm axially and 1.5 cm superior/inferior for FBCT-based plans to incorporate setup errors and an estimate of respiratory-mediated tumor motion vs 8 mm isotropic margin for setup error only in all 4D-CT plans. The 3DCRT plans generated from the FBCT scan were copied on the 4D-CT data set with the same beam parameters. GTV_3D, IGTV_4D, PTV, and dose volume histogram from both data sets were analyzed and compared. Dice coefficient evaluated PTV similarity between FBCT and 4D-CT data sets. Results: In total, 14 of the 15 patients were analyzed. One patient was excluded as there was no measurable GTV. Mean GTV_3D was 115.3 cm 3 and mean IGTV_4D was 152.5 cm 3 ( P = .001. Mean PTV_3D was 530.0 cm 3 and PTV_4D was 499.8 cm 3 ( P = .40. Both gross primary and nodal disease analyzed separately were larger

  12. Prognostic role of adjuvant radiotherapy in triple-negative breast cancer : A historical cohort study

    NARCIS (Netherlands)

    Bhoo Pathy, Nirmala; Verkooijen, Helena M.|info:eu-repo/dai/nl/213707705; Wong, Fuh-Yong; Pignol, Jean-Philippe; Kwong, Ava; Tan, Ern-Yu; Taib, Nur Aishah; Nei, Wen-Long; Ho, Gwo-Fuang; Tan, Benita; Chan, Patrick; Lee, Soo-Chin; Hartman, Mikael; Yip, Cheng-Har; Dent, Rebecca

    2015-01-01

    The value of adjuvant radiotherapy in triple-negative breast cancer (TNBC) is currently debated. We assessed the association between adjuvant radiotherapy and survival in a large cohort of Asian women with TNBC. Women diagnosed with TNBC from 2006 to 2011 in five Asian centers (N=1,138) were

  13. Factors influencing time between surgery and radiotherapy : A population based study of breast cancer patients

    NARCIS (Netherlands)

    Katik, S.; Gort, M.; Jobsen, J. J.; Maduro, J. H.; Struikmans, H.; Siesling, S.

    This study describes variation in the time interval between surgery and radiotherapy in breast cancer (BC) patients and assesses factors at patient, hospital and radiotherapy centre (RTC) level influencing this variation. To do so, the factors were investigated in BC patients using multilevel

  14. Resting energy expenditure in head and neck cancer patients before and during radiotherapy

    NARCIS (Netherlands)

    Langius, Jacqueline A. E.; Kruizenga, Hinke M.; Uitdehaag, Bernard M. J.; Langendijk, Johannes A.; Doornaert, Patricia; Leemans, C. Rene; Weijs, Peter J. M.

    Background & aims: Weight loss is a frequently observed problem in patients with head and neck cancer (HNC) during radiotherapy. It is still to be assessed whether hypermetabolism is contributing to this problem. The aim of this study was to investigate hypermetabolism before radiotherapy, and

  15. Parotid-sparing intensity modulated versus conventional radiotherapy in head and neck cancer (PARSPORT): a phase 3 multicentre randomised controlled trial

    OpenAIRE

    Nutting, Christopher M; Morden, James P; Harrington, Kevin J; Urbano, Teresa Guerrero; Bhide, Shreerang A; Clark, Catharine; Miles, Elizabeth A; Miah, Aisha B; Newbold, Kate; Tanay, MaryAnne; Adab, Fawzi; Jefferies, Sarah J; Scrase, Christopher; Yap, Beng K; A'Hern, Roger P

    2011-01-01

    Summary Background Xerostomia is the most common late side-effect of radiotherapy to the head and neck. Compared with conventional radiotherapy, intensity-modulated radiotherapy (IMRT) can reduce irradiation of the parotid glands. We assessed the hypothesis that parotid-sparing IMRT reduces the incidence of severe xerostomia. Methods We undertook a randomised controlled trial between Jan 21, 2003, and Dec 7, 2007, that compared conventional radiotherapy (control) with parotid-sparing IMRT. We...

  16. Adaptive Motion Compensation in Radiotherapy

    CERN Document Server

    Murphy, Martin J

    2011-01-01

    External-beam radiotherapy has long been challenged by the simple fact that patients can (and do) move during the delivery of radiation. Recent advances in imaging and beam delivery technologies have made the solution--adapting delivery to natural movement--a practical reality. Adaptive Motion Compensation in Radiotherapy provides the first detailed treatment of online interventional techniques for motion compensation radiotherapy. This authoritative book discusses: Each of the contributing elements of a motion-adaptive system, including target detection and tracking, beam adaptation, and pati

  17. Radiotherapy for hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Tokuuye, Koichi; Sumi, Minako; Kagami, Yoshikazu; Murayama, Shigeyuki [National Cancer Center Hospital, Tokyo (Japan). Radiation Oncology Div.; Kawashima, Mitsuhiko; Ikeda, Hiroshi [National Cancer Center Hospital East, Chiba (Japan). Radiation Div.; Ueno, Hideki; Okusaka, Takuji; Okada, Shuichi [National Cancer Center Hospital, Tokyo (Japan). Internal Medicine Div.

    2000-09-01

    Purpose: To retrospectively evaluate the effectiveness of radiotherapy with or without transarterial embolization (TAE) and/or percutaneous ethanol injection (PEI) in patients with hepatocellular carcinoma who were ineligible for surgery. Patients and Methods: From October 1984 to November 1997, 62 patients underwent radiotherapy receiving 50 to 70 Gy in 25 to 35 treatments with or without transarterial embolization and/or percutaneous ethanol injection and were followed for a median period of 8.6 months (1.5 to 92 months). Results: Overall median survival rates were 9.5 months. Significant prognostic factors were the extent of pretreatment liver function impairment, radiation field size and the existence of tumor thrombosis. Six-month and 1-year local control rates were 67 and 54%, respectively. Seven of the 8 patients who suffered from hepatic failure had poor pretreatment liver functions. Conclusion: Radiotherapy with or without transarterial embolization and/or percutaneous ethanol injection appears effective in controlling hepatocellular carcinoma and prolonged survival. Individualized treatment strategies are presented depending on the tumor presentation and the degree of liver function impairment. (orig.) [German] Hintergrund: Retrospektive Evaluierung der Wirksamkeit einer Bestrahlung mit oder ohne transarterielle Embolisation oder perkutaner Alkoholinjektion bei Patienten mit inoperablem hepatozellulaeren Karzinom. Patienten und Methodik: Von Oktober 1984 bis November 1997 wurden 62 Patienten mit einer Gesamtdosis von 50 bis 70 Gy in 25 bis 35 Fraktionen mit oder ohne transarterielle Embolisation oder perkutane Alkoholinjektion behandelt. Der mediane Follow-up betrug 8,6 Monate (1,5 bis 92 Monate). Ergebnisse: Das mediane Gesamtueberleben betrug 9,5 Monate. Signifikante prognostische Einflussfaktoren waren das Ausmass der praetherapeutischen Leberfunktionseinschraenkung, die Bestrahlungsfeldgroesse und das Vorhandensein von Tumorthrombosen. Nach sechs

  18. Global Access to Radiotherapy Services: Have We Made Progress During the Past Decade?

    Science.gov (United States)

    Zubizarreta, Eduardo; Bray, Freddie; Ferlay, Jacques; Barton, Michael

    2016-01-01

    Purpose The global incidence of cancer is rising, particularly in low- and middle-income countries. Radiotherapy is an important cancer treatment in the curative and palliative setting. We aimed to estimate the global demand for and supply of radiotherapy megavoltage machines (MVMs) and assess the changes in supply and demand during the past decade. Materials and Methods Cancer incidences for 27 cancer types in 184 countries were extracted from the International Agency for Research on Cancer GLOBOCAN database. The Collaboration for Cancer Outcomes Research and Evaluation radiotherapy utilization rate (RTU) model was used to estimate the number of patients in each country with an indication for radiotherapy for each cancer type and estimate the demand for MVMs. The radiotherapy supply data were accessed from Directory of Radiotherapy Centres database maintained by the International Atomic Energy Agency. Results RTU varied by country, from 32% in Mongolia to 59% in Comoros. The average optimal world RTU was 50%, equating to 7 million people in 2012 who would benefit from radiotherapy. There remains a deficit of more than 7,000 machines worldwide. During the past decade, the gap between radiotherapy demand and supply has widened in low-income countries. Conclusion RTU varies significantly between countries. Approximately half of all patients with cancer worldwide should receive radiotherapy; however, more than 2 million people are unable to access it because of a lack of MVMs. Low- and middle-income countries are particularly disadvantaged by this deficit. PMID:28717703

  19. [Radiotherapy for nasopharyngeal carcinoma].

    Science.gov (United States)

    Maingon, P; Blanchard, P; Bidault, F; Calmels, L

    2016-09-01

    Nasapharyngeal carcinoma is a rare disease. Oftenly, the diagnostic is made for advanced disease. Localized tumors, T1 or T2 NO observed a good prognosis and are locally controlled in more than 90 % of the cases by radiotherapy alone. The standard treatment of locally advanced disease is combined chemoradiation. A special vigilance of fast decrease of the volume of the pathological lymph nodes, sometimes associated to loss of weight might indicate an adaptive dosimetric revision. The treatment of recurrent disease is of great importance. Surgical indications are limited but should be discussed in multidisciplinary tumor board when possible. Surgical nodal sampling has to be proposed for nodal recurrence as well as reirradiation, which could be indicated according to the technical issues. Copyright © 2016. Published by Elsevier SAS.

  20. [Radiotherapy during pregnancy].

    Science.gov (United States)

    Mazeron, R; Barillot, I; Mornex, F; Giraud, P

    2016-09-01

    The diagnostic of cancer during pregnancy is a rare and delicate situation. As the developments of the embryo and the human fetus are extremely sensitive to ionizing radiations, the treatment of these tumors should be discussed. The studies - preclinical and clinical - based mostly on exposure accidents show that subdiaphragmatic treatments are possible during pregnancy. When radiotherapy is used, phantom estimations of the dose to the fetus, confirmed by in vivo measurements are required. Irradiation and imaging techniques should be arranged to decrease as much as possible the dose delivered to the fetus and hold below the threshold of 0.1Gy. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  1. Targeted intraoperative radiotherapy in oncology

    CERN Document Server

    Keshtgar, Mohammed; Wenz, Frederik

    2014-01-01

    Targeted intraoperative radiotherapy is a major advance in the management of cancer patients. With an emphasis on practical aspects, this book offers an ideal introduction to this innovative  technology for clinicians.

  2. [Combined radiotherapy of uveal melanoma].

    Science.gov (United States)

    Brovkina, A F; Kesheleva, V V; Fridman, F E; Fishkin, I G

    1997-01-01

    Fifteen patients with uveal melanoma were exposed to combined radiotherapy: transscleral exposure of melanoma using a ruthenium ophthalmoapplicator and intracorporeal administration of 59Fe. Radiation reaction of the tumor was potentiated by combined exposure.

  3. Bone Health and Pelvic Radiotherapy.

    Science.gov (United States)

    Higham, C E; Faithfull, S

    2015-11-01

    Survivors who have received pelvic radiotherapy make up many of the long-term cancer population, with therapies for gynaecological, bowel, bladder and prostate malignancies. Individuals who receive radiotherapy to the pelvis as part of their cancer treatment are at risk of insufficiency fractures. Symptoms of insufficiency fractures include pelvic and back pain and immobility, which can affect substantially quality of life. This constellation of symptoms can occur within 2 months of radiotherapy up to 63 months post-treatment, with a median incidence of 6-20 months. As a condition it is under reported and evidence is poor as to the contributing risk factors, causation and best management to improve the patient's bone health and mobility. As radiotherapy advances, chronic symptoms, such as insufficiency fractures, as a consequence of treatment need to be better understood and reviewed. This overview explores the current evidence for the effect of radiotherapy on bone health and insufficiency fractures and identifies what we know and where gaps in our knowledge lie. The overview concludes with the need to take seriously complaints of pelvic pain from patients after pelvic radiotherapy and to investigate and manage these symptoms more effectively. There is a clear need for definitive research in this field to provide the evidence-based guidance much needed in practice. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  4. Evaluation of urologic morbidity after radiotherapy for cervical carcinoma by urodynamic examinations and patient voiding schemes: a prospective study

    DEFF Research Database (Denmark)

    Lajer, Henrik; Thranov, Ingrid R; Bagi, Per

    2002-01-01

    To assess urologic morbidity in a 5-year period by urodynamic examinations and patient voiding schemes after radiotherapy and brachytherapy for cervical carcinoma.......To assess urologic morbidity in a 5-year period by urodynamic examinations and patient voiding schemes after radiotherapy and brachytherapy for cervical carcinoma....

  5. Radioprotectors in Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nair, C.K.K. [Bhabha Atomic Research Centre, Mumbai (India); Parida, D.K.; Nomura, Taisei

    2001-03-01

    This review article focuses on clinically relevant radioprotectors and their mechanisms of radioprotection. Radiotherapy is the most common modality of human cancer therapy. Obtaining optimal results requires a judicious balance between the total dose of radiotherapy delivered and the threshold limit of critical surrounding normal tissues, and the normal tissues need to be protected against radiation injury to obtain better tumor control by using a higher dose. For this reason, radiation-protective agents play an important role in clinical radiotherapy. Radiation-protective agents can be classified into three groups: radioprotectors, adaptogens, and absorbents. The first group generally consists of sulfhydryl compounds and other antioxidants. They include several myelo-, entero-, and cerebro-protectors. Adaptogens act as promotors of radioresistance. They are natural protectors that offer chemical protection against low levels of ionizing radiation. Absorbents protect organs from internal radiation and chemicals. They include drugs that prevent incorporation of radioiodine by the thyroid gland and absorption of radionuclides. This article thoroughly describes the properties, mechanisms of action, and perspectives on clinical application of the following categories of radioprotectors: sulfhydryl compounds (e.g., cysteine, cysteamine, glutathione, AET, WR 2127, and other WR-compounds), antioxidants (e.g., tempace, Hoechst 33342, vitamin A, E, and C, TMG, melatonin), angiotensin-converting enzyme (ACE) inhibitors (e.g., captopril, elanopril, penicillamine, pentoxifylline, L-158, 809), cytoprotective agents (mesna, dexrazoxane, and amifostin), metalloelements (e.g., manganese chloride, cadmium salts, bismuth subnitrate), immunomodulators (gamma-interferon, polysaccharides AM5, AM218, heat-killed lactobacillus cells, broncho-vaxom, trehalose dicorynomycolate, and AS101), lipopolysaccharides and prostaglandins, plant extracts and compounds isolated from plants (curcmin

  6. Technological advances in radiotherapy for esophageal cancer

    Science.gov (United States)

    Vosmik, Milan; Petera, Jiri; Sirak, Igor; Hodek, Miroslav; Paluska, Petr; Dolezal, Jiri; Kopacova, Marcela

    2010-01-01

    Radiotherapy with concurrent chemotherapy and surgery represent the main treatment modalities in esophageal cancer. The goal of modern radiotherapy approaches, based on recent technological advances, is to minimize post-treatment complications by improving the gross tumor volume definition (positron emission tomography-based planning), reducing interfraction motion (image-guided radiotherapy) and intrafraction motion (respiratory-gated radiotherapy), and by better dose delivery to the precisely defined planning target volume (intensity-modulated radiotherapy and proton therapy). Reduction of radiotherapy-related toxicity is fundamental to the improvement of clinical results in esophageal cancer, although the dose escalation concept is controversial. PMID:21105188

  7. Effect of different breathing patterns in the same patient on stereotactic ablative body radiotherapy dosimetry for primary renal cell carcinoma: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Daniel, E-mail: Daniel.Pham@petermac.org [Radiotherapy Services, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Kron, Tomas [Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Foroudi, Farshad; Siva, Shankar [Radiation Oncology, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia)

    2013-10-01

    Stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) targets requires motion management strategies to verify dose delivery. This case study highlights the effect of a change in patient breathing amplitude on the dosimetry to organs at risk and target structures. A 73-year-old male patient was planned for receiving 26 Gy of radiation in 1 fraction of SABR for a left primary RCC. The patient was simulated with four-dimensional computed tomography (4DCT) and the tumor internal target volume (ITV) was delineated using the 4DCT maximum intensity projection. However, the initially planned treatment was abandoned at the radiation oncologist's discretion after pretreatment cone-beam CT (CBCT) motion verification identified a greater than 50% reduction in superior to inferior diaphragm motion as compared with the planning 4DCT. This patient was resimulated with respiratory coaching instructions. To assess the effect of the change in breathing on the dosimetry to the target, each plan was recalculated on the data set representing the change in breathing condition. A change from smaller to larger breathing showed a 46% loss in planning target volume (PTV) coverage, whereas a change from larger breathing to smaller breathing resulted in an 8% decrease in PTV coverage. ITV coverage was similarly reduced by 8% in both scenarios. This case study highlights the importance of tools to verify breathing motion prior to treatment delivery. 4D image guided radiation therapy verification strategies should focus on not only verifying ITV margin coverage but also the effect on the surrounding organs at risk.

  8. Effect of different breathing patterns in the same patient on stereotactic ablative body radiotherapy dosimetry for primary renal cell carcinoma: a case study.

    Science.gov (United States)

    Pham, Daniel; Kron, Tomas; Foroudi, Farshad; Siva, Shankar

    2013-01-01

    Stereotactic ablative body radiotherapy (SABR) for primary renal cell carcinoma (RCC) targets requires motion management strategies to verify dose delivery. This case study highlights the effect of a change in patient breathing amplitude on the dosimetry to organs at risk and target structures. A 73-year-old male patient was planned for receiving 26Gy of radiation in 1 fraction of SABR for a left primary RCC. The patient was simulated with four-dimensional computed tomography (4DCT) and the tumor internal target volume (ITV) was delineated using the 4DCT maximum intensity projection. However, the initially planned treatment was abandoned at the radiation oncologist's discretion after pretreatment cone-beam CT (CBCT) motion verification identified a greater than 50% reduction in superior to inferior diaphragm motion as compared with the planning 4DCT. This patient was resimulated with respiratory coaching instructions. To assess the effect of the change in breathing on the dosimetry to the target, each plan was recalculated on the data set representing the change in breathing condition. A change from smaller to larger breathing showed a 46% loss in planning target volume (PTV) coverage, whereas a change from larger breathing to smaller breathing resulted in an 8% decrease in PTV coverage. ITV coverage was similarly reduced by 8% in both scenarios. This case study highlights the importance of tools to verify breathing motion prior to treatment delivery. 4D image guided radiation therapy verification strategies should focus on not only verifying ITV margin coverage but also the effect on the surrounding organs at risk. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  9. Retrospective study of 48 cases of post-operative radiotherapy for head and neck cancer; Etude retrospective a propos de 48 cas de radiotherapie postoperatoire pour cancer de la tete et du cou

    Energy Technology Data Exchange (ETDEWEB)

    Mnejja, W.; Yahiaoui, S.; Siala, W.; Daoud, J. [Service de radiotherapie carcinologique, EPS Habib-Bourguiba, Sfax (Tunisia); Ghorbel, A.; Frikha, M. [Service de carcinologie medicale, EPS Habib-Bourguiba, Sfax (Tunisia)

    2011-10-15

    The authors report a study which aimed at assessing therapeutic results after post-operative radiotherapy of 48 patients suffering from head and neck cancers. The analysis is made in terms of cancer control, survival without recurrence and global survival. The post-operative radiotherapy improves the disease control rate. Ganglionary attack and capsular failure are survival prognosis factors. The concomitant association of chemo-therapy and radiotherapy should improve therapeutic results. Short communication

  10. Radiation therapy in elderly patients; Radiotherapie et sujet age

    Energy Technology Data Exchange (ETDEWEB)

    Durdux, C.; Boisserie, T. [Hopital Europeen Georges-Pompidou, Service de Radiotherapie, 75 - Paris (France); Gisselbrecht, M. [Hopital Europeen Georges-Pompidou, Service de Geriatrie, 75 - Paris (France)

    2009-10-15

    Cancer is a disease that predominantly occurs in older patients who represent a quarter of the population in western countries. Numerous types of cancer are observed in elderly people. Radiotherapy is one of the most powerful treatment against cancer. Most of published studies have demonstrated feasibility of radiotherapy in curative or palliative intent whatever cancer types are considered. Complete geriatric assessment and a multidisciplinary approach are the key points. The purpose of this review is to highlight sights of radiation oncology specifically related to aging. Particular emphasis is placed on logistic and technical aspects of radiation, as dose, irradiated volume and fractionation. (authors)

  11. Patterns of retreatment by radiotherapy.

    Science.gov (United States)

    Barton, M B; Allen, S; Delaney, G P; Hudson, H M; Hao, Z; Allison, R W; van der Linden, Y M

    2014-10-01

    To describe patterns of treatment for those who receive more than one episode of megavoltage radiotherapy (retreatment) by cancer type for better service planning and benchmarking. Institutional databases of all patients who received their first megavoltage radiotherapy for any type of cancer at the Liverpool and Macarthur Cancer Therapy Centres (LM), New South Wales, Australia, Royal Brisbane and Women's Hospital (RBWH), Queensland, Australia and Radiotherapeutic Institution Friesland (RIF), Leeuwarden, the Netherlands, over the period 1991-2009 were examined. Radiotherapy retreatment was defined as any radiotherapy episode, to any body site, after an initial episode of radiotherapy, for the same cancer diagnosis. The total retreatment rate was defined as the number of retreatment episodes of radiotherapy divided by the number of cases in the cohort. In total, 62,270 patients (RBWH 38581, LM 9654, RIF 14035) received 77,762 episodes of radiotherapy, giving a total retreatment rate of 0.25; 52,351 patients (84%) received only one episode of treatment and 9919 (16%) received two or more episodes of treatment. Overall retreatment rates for LM, RBWH and RIF were 0.24, 0.25 and 0.26, respectively. For the five most common cancer types treated, the median time between treatment episodes was longest for breast cancer (11.3 months), then head and neck cancer (9.7 months), colorectal cancer (7.2 months), prostate cancer (4.4 months) and lung cancer (4.1 months). Ninety-one per cent of all fractions were delivered in the first episode of treatment. The retreatment rate was very similar between the three facilities, suggesting agreement about the indications for retreatment. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  12. Chemotherapy alone versus chemotherapy plus radiotherapy for adults with early stage Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Blank, Oliver; von Tresckow, Bastian; Monsef, Ina

    2017-01-01

    BACKGROUND: Combined modality treatment consisting of chemotherapy followed by localised radiotherapy is the standard treatment for patients with early stage Hodgkin lymphoma (HL). However, due to long- term adverse effects such as secondary malignancies the role of radiotherapy has been questioned...... recently and some clinical study groups advocate chemotherapy only for this indication. OBJECTIVES: To assess the effects of chemotherapy alone compared to chemotherapy plus radiotherapy in adults with early stage HL . SEARCH METHODS: For the or i ginal version of this review, we searched MEDLINE, Embase...... radiotherapy. For the updated review we searched MEDLINE, CENTRAL and conference proceedings to December 2016. SELECTION CRITERIA: We included RCTs comparing chemotherapy alone with chemotherapy plus radiotherapy in patients with early stage HL. We excluded trials with more than 20% of patients in advanced...

  13. [Dose reconstruction using respiratory signals and machine parameters during treatment in stereotactic body radiotherapy].

    Science.gov (United States)

    Imae, Toshikazu; Haga, Akihiro; Saotome, Naoya; Kida, Satoshi; Nakano, Masahiro; Takenaka, Shigeharu; Takeuchi, Yukihiro; Shiraki, Takashi; Yano, Keiichi; Yamashita, Hideomi; Nakagawa, Keiichi; Ohtomo, Kuni

    2014-11-01

    Volumetric modulated arc therapy (VMAT) is a rotational intensity-modulated radiotherapy (IMRT) technique capable of acquiring projection images during treatment. The purpose of this study was to reconstruct the dose distribution from respiratory signals and machine parameters acquired during stereotactic body radiotherapy (SBRT). The treatment plans created for VMAT-SBRT included the constraint of 1 mm/degree in multileaf collimator (MLC) for a moving phantom and three patients with lung tumors. The respiratory signals were derived from projection images acquired during VMAT delivery, while the machine parameters were derived from machine logs. The respiratory signals and machine parameters were then linked along with the gantry angle. With this data, the dose distribution of each respiratory phase was calculated on the planned four-dimensional CT (4D CT). The doses at the isocenter, the point of max dose and the centroid of the target were compared with those of the corresponding plans. In the phantom study, the maximum dose difference between the plan and "in-treatment" results was -0.4% at the centroid of the target. In the patient study, the difference was -1.8 ± 0.4% at the centroid of the target. Dose differences of the evaluated points between 4 and 10 phases were not significant. The present method successfully reconstructed the dose distribution using the respiratory signals and machine parameters acquired during treatment. This is a feasible method for verifying the actual dose for a moving target.

  14. Pulmonary oligometastases : Metastasectomy or stereotactic ablative radiotherapy?

    NARCIS (Netherlands)

    Widder, Joachim; Klinkenberg, Theo J.; Ubbels, Jan F.; Wiegman, Erwin M.; Groen, Harry J. M.; Langendijk, Johannes A.

    Background and purpose: Stereotactic ablative radiotherapy (SABR; or stereotactic body radiotherapy, SBRT) emerges as treatment option for pulmonary oligometastatic disease (OMD), but there are no studies comparing SABR with pulmonary metastasectomy (PME). We analysed consecutive patients referred

  15. Radiotherapy for glomus jugulare paraganglioma.

    Science.gov (United States)

    Tran Ba Huy, P

    2014-09-01

    Surgery has been long considered to be the treatment of choice for glomus jugulare paragangliomas, as it is the only modality able to totally eradicate the tumour. However, despite considerable progress in interventional radiology and nerve monitoring, surgery is associated with an unacceptably high complication rate for a benign tumour, explaining the growing place of radiotherapy in the management of these tumours. This review of the literature confirms the efficacy of conformal radiotherapy with or without intensity modulation and stereotactic radiotherapy, which both achieve tumour control rates ranging from 90% to almost 100% of cases, but for different tumour volumes, almost constant stabilization or even improvement of symptoms, and a considerably lower rate of adverse effects than with surgery. However, radiotherapy remains contraindicated in the presence of intracranial invasion or extensive osteomyelitis. In the light of these results, together with the improved quality of life and a better knowledge of the natural history of this disease, many authors propose radiotherapy as first-line treatment for all glomus jugulare paragangliomas regardless of their size, particularly in patients with no preoperative deficits. Copyright © 2014. Published by Elsevier Masson SAS.

  16. Incidence of dermatitis in head and neck cancer patients treated with primary radiotherapy and cetuximab

    Energy Technology Data Exchange (ETDEWEB)

    Selzer, Edgar; Liederer Susanne; Lemaire, Christiane; Radonjic, Dejan; Poetter, Richard; Bachtiary, Barbara [Medical Univ. Vienna (Austria). Dept. of Radiotherapy; Kren, Gerhard; Knocke, Thomas [Hospital Hietzing, Vienna (Austria). Dept. of Radiotherapy; Kornek, Gabriela [Medical Univ. Vienna (Austria). Dept. of Internal Medicine I

    2011-06-15

    To retrospectively assess the incidence of radiation dermatitis in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) who received primary radiotherapy in combination with cetuximab in a curative intent. A total of 112 consecutively treated patients who received cetuximab in combination with radiotherapy at the Departments of Radiotherapy at the Medical University in Vienna and the Hospital Hietzing (Vienna) were analyzed. Radiotherapy was administered either as conventional radiotherapy (70 Gy in 7 weeks) or using a concomitant boost protocol (72 Gy in 6 weeks). The incidence of dermatitis and mucositis within the radiation portals in 103 eligible patients was compared with a historical control group treated at the Medical University of Vienna as well as with published data. The incidence of grade 1/2, 3, and 4 dermatitis was 57%, 29%, and 1% in the radiotherapy plus cetuximab treated collective. The incidence of grade 1/2, 3, and 4 mucositis was 37%, 47%, and 4%, respectively. The incidence of grade 3 dermatitis during concurrent radiotherapy plus cetuximab was 29% in our patient collective. Only one case of grade 4 dermatitis was observed. These results do not statistically differ significantly from the incidence reported in the Bonner trial and indicate that cetuximab in combination with radiotherapy is well tolerated. (orig.)

  17. Kombinierte Angiogenese-/Vaskulogenese-Inhibition und Radiotherapie

    OpenAIRE

    Riesterer, O

    2011-01-01

    Im folgenden Artikel wird die Interaktion von Inhibitoren der Angiogenese oder Vaskulogenese in Kombination mit Radiotherapie vorgestellt und anhand des jeweiligen Interaktionsmechanismus aufgezeigt, wie diese Substanzen in klinische Studien zusammen mit Radiotherapie integriert werden können. Besonders wird dabei auf einen neuen Therapieansatz eingegangen: die ergänzende (adjuvante) Gabe von Angiogenese- oder Vaskulogenese-Inhibitoren nach Abschluss der fraktionierten Radiotherapie.

  18. Severe mitral regurgitation after radiotherapy.

    Science.gov (United States)

    Cozzarín, Alberto; Cianciulli, Tomás F; Saccheri, María C; Lax, Jorge A; Simonetti, Mario E; Zappi, Andrea; Laguens, Rubén P

    2014-02-01

    We present the case of a 69-year-old patient with a history of gynecological neoplasia and a pulmonary metastasis, who in 1996 underwent chemotherapy and mediastinal radiotherapy followed by cancer remission. Ten years later she presented with heart failure and her Doppler echocardiogram showed severe mitral regurgitation with pulmonary hypertension. In 2011, she underwent a mitral valve replacement with a biological prosthesis and the pathology exam revealed valve damage consistent with radiotherapy-induced changes. This unusual mechanism of mitral regurgitation can be demonstrated clearly by echocardiography and should be disseminated among cardiology physicians and in patients who have survived for long periods after radiotherapy, it is important to remember that cardiac complications may indeed occur, and the treating physician is responsible for detecting them. © 2013, Wiley Periodicals, Inc.

  19. Voice quality after endoscopic laser surgery and radiotherapy for early glottic cancer: objective measurements emphasizing the Voice Handicap Index

    Science.gov (United States)

    Caminero Cueva, Maria Jesús; Señaris González, Blanca; Llorente Pendás, José Luis; Gorriz Gil, Carmen; López Llames, Aurora; Alonso Pantiga, Ramón; Suárez Nieto, Carlos

    2007-01-01

    We analyzed the functional outcome and self-evaluation of the voice of patients with T1 glottic carcinoma treated with endoscopic laser surgery and radiotherapy. We performed an objective voice evaluation, as well as a physical, emotional and functional well being assessment of 19 patients treated with laser surgery and 18 patients treated with radiotherapy. Voice quality is affected both by surgery and radiotherapy. Voice parameters only show differences in the maximum phonation time between both treatments. Results in the Voice Handicap Index show that radiotherapy has less effect on patient voice quality perception. There is a reduced impact on the patient’s perception of voice quality after radiotherapy, despite there being no significant differences in vocal quality between radiotherapy and laser cordectomy. PMID:17999074

  20. Clinical quality standards for radiotherapy

    Science.gov (United States)

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  1. Metrological Issues in Molecular Radiotherapy

    Directory of Open Access Journals (Sweden)

    D’Arienzo Marco

    2014-01-01

    Full Text Available The therapeutic effect from molecular radiation therapy (MRT, on both tumour and normal tissue, is determined by the radiation absorbed dose. Recent research indicates that as a consequence of biological variation across patients the absorbed dose can vary, for the same administered activity, by as much as two orders of magnitude. The international collaborative EURAMET-EMRP project “Metrology for molecular radiotherapy (MetroMRT” is addressing this problem. The overall aim of the project is to develop methods of calibrating and verifying clinical dosimetry in MRT. In the present paper an overview of the metrological issues in molecular radiotherapy is provided.

  2. Efficacy of low-dose radiotherapy in painful gonarthritis: experiences from a retrospective East German bicenter study

    Science.gov (United States)

    2013-01-01

    Purpose To evaluate the efficacy of low-dose radiotherapy in painful gonarthritis. Methods We assessed the medical records of 1037 patients with painful gonarthritis who had undergone low-dose radiotherapy between 1981 and 2008. The subjective patient perception of the response to irradiation as graded immediately or up to two months after the completion of a radiotherapy series was evaluated and correlated with age, gender, radiological grading and the duration of symptoms before radiotherapy. Moreover, we performed a mail survey to obtain additional long-term follow-up information and received one hundred and six evaluable questionnaires. Results We assessed 1659 series of radiotherapy in 1037 patients. In 79.3% of the cases the patients experienced a slight, marked or complete pain relief immediately or up to two months after the completion of radiotherapy. Gender, age and the duration of pain before radiotherapy did not have a significant influence on the response to irradiation. In contrast, severe signs of osteoarthritis were associated with more effective pain relief. In more than 50% of the patients who reported a positive response to irradiation a sustained period of symptomatic improvement was observed. Conclusions Our results confirm that low-dose radiotherapy is an effective treatment for painful osteoarthritis of the knee. In contrast to an earlier retrospective study, severe signs of osteoarthritis constituted a positive prognostic factor for the response to irradiation. A randomized trial is urgently required to compare radiotherapy with other treatment modalities. PMID:23369282

  3. Efficacy of low-dose radiotherapy in painful gonarthritis: experiences from a retrospective East German bicenter study

    Directory of Open Access Journals (Sweden)

    Keller Stephanie

    2013-01-01

    Full Text Available Abstract Purpose To evaluate the efficacy of low-dose radiotherapy in painful gonarthritis. Methods We assessed the medical records of 1037 patients with painful gonarthritis who had undergone low-dose radiotherapy between 1981 and 2008. The subjective patient perception of the response to irradiation as graded immediately or up to two months after the completion of a radiotherapy series was evaluated and correlated with age, gender, radiological grading and the duration of symptoms before radiotherapy. Moreover, we performed a mail survey to obtain additional long-term follow-up information and received one hundred and six evaluable questionnaires. Results We assessed 1659 series of radiotherapy in 1037 patients. In 79.3% of the cases the patients experienced a slight, marked or complete pain relief immediately or up to two months after the completion of radiotherapy. Gender, age and the duration of pain before radiotherapy did not have a significant influence on the response to irradiation. In contrast, severe signs of osteoarthritis were associated with more effective pain relief. In more than 50% of the patients who reported a positive response to irradiation a sustained period of symptomatic improvement was observed. Conclusions Our results confirm that low-dose radiotherapy is an effective treatment for painful osteoarthritis of the knee. In contrast to an earlier retrospective study, severe signs of osteoarthritis constituted a positive prognostic factor for the response to irradiation. A randomized trial is urgently required to compare radiotherapy with other treatment modalities.

  4. Recommendations for safer radiotherapy: what’s the message?

    Directory of Open Access Journals (Sweden)

    Peter eDunscombe

    2012-09-01

    Full Text Available Radiotherapy, with close to a million courses delivered per year in North America, is a very safe and effective intervention for a devastating disease. However, although rare, several deeply regrettable incidents have occurred in radiotherapy and have rightly been the subject of considerable public interest. Partly in response to reports of these incidents a variety of authoritative organizations across the globe has harnessed the expertise amongst their members in attempts to identify the measures that will make radiotherapy safer. While the intentions of all these organizations are clearly good it is challenging for the health care providers in the clinic to know where to start with so much advice coming from so many directions. Through a mapping exercise we have identified commonalities between recommendations made in seven authoritative documents and identified those issues most frequently cited. The documents reviewed contain a total of 117 recommendations. Using the 37 recommendations in Towards Safer Radiotherapy as the initial base layer, recommendations in the other documents were mapped, adding to the base layer to accommodate all the recommendations from the additional six documents as necessary. This mapping exercise resulted in the distillation of the original 117 recommendations down to 61 unique recommendations. Twelve topics were identified in three or more of the documents as being pertinent to the improvement of patient safety in radiotherapy. They are, in order of most to least cited: training, staffing, documentation, incident learning, communication, check lists, quality control and preventive maintenance, dosimetric audit, accreditation, minimizing interruptions, prospective risk assessment and safety culture. This analysis provides guidance for the selection of those activities most likely to enhance safety and quality in radiotherapy based on the frequency of citation in selected recent authoritative literature.

  5. Unilateral Radiotherapy for the Treatment of Tonsil Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chronowski, Gregory M., E-mail: gchronowski@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Garden, Adam S.; Morrison, William H.; Frank, Steven J. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Schwartz, David L. [Department of Radiation Medicine, Long Island Jewish Hospital (United States); Shah, Shalin J.; Beadle, Beth M.; Gunn, G. Brandon [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Kupferman, Michael E. [Department of Head and Neck Surgery, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Ang, Kian K.; Rosenthal, David I. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)

    2012-05-01

    Purpose: To assess, through a retrospective review, clinical outcomes of patients with squamous cell carcinoma of the tonsil treated at the M. D. Anderson Cancer Center with unilateral radiotherapy techniques that irradiate the involved tonsil region and ipsilateral neck only. Methods and Materials: Of 901 patients with newly diagnosed squamous cell carcinoma of the tonsil treated with radiotherapy at our institution, we identified 102 that were treated using unilateral radiotherapy techniques. All patients had their primary site of disease restricted to the tonsillar fossa or anterior pillar, with <1 cm involvement of the soft palate. Patients had TX (n = 17 patients), T1 (n = 52), or T2 (n = 33) disease, with Nx (n = 3), N0 (n = 33), N1 (n = 23), N2a (n = 21), or N2b (n = 22) neck disease. Results: Sixty-one patients (60%) underwent diagnostic tonsillectomy before radiotherapy. Twenty-seven patients (26%) underwent excision of a cervical lymph node or neck dissection before radiotherapy. Median follow-up for surviving patients was 38 months. Locoregional control at the primary site and ipsilateral neck was 100%. Two patients experienced contralateral nodal recurrence (2%). The 5-year overall survival and disease-free survival rates were 95% and 96%, respectively. The 5-year freedom from contralateral nodal recurrence rate was 96%. Nine patients required feeding tubes during therapy. Of the 2 patients with contralateral recurrence, 1 experienced an isolated neck recurrence and was salvaged with contralateral neck dissection only and remains alive and free of disease. The other patient presented with a contralateral base of tongue tumor and involved cervical lymph node, which may have represented a second primary tumor, and died of disease. Conclusions: Unilateral radiotherapy for patients with TX-T2, N0-N2b primary tonsil carcinoma results in high rates of disease control, with low rates of contralateral nodal failure and a low incidence of acute toxicity

  6. Oral cancer: Current role of radiotherapy and chemotherapy.

    Science.gov (United States)

    Huang, Shao-Hui; O'Sullivan, Brian

    2013-03-01

    The term oral cavity cancer (OSCC) constitutes cancers of the mucosal surfaces of the lips, floor of mouth, oral tongue, buccal mucosa, lower and upper gingiva, hard palate and retromolar trigone. Treatment approaches for OSCC include single management with surgery, radiotherapy [external beam radiotherapy (EBRT) and/or brachytherapy], as well as adjuvant systemic therapy (chemotherapy and/or target agents); various combinations of these modalities may also be used depending on the disease presentation and pathological findings. The selection of sole or combined modality is based on various considerations that include disease control probability, the anticipated functional and cosmetic outcomes, tumor resectability, patient general condition, and availability of resources and expertise. For resectable OSCC, the mainstay of treatment is surgery, though same practitioners may advocate for the use of radiotherapy alone in selected "early" disease presentations or combined with chemotherapy in more locally advanced stage disease. In general, the latter is more commonly reserved for cases where surgery may be problematic. Thus, primary radiotherapy ± chemotherapy is usually reserved for patients unable to tolerate or who are otherwise unsuited for surgery. On the other hand, brachytherapy may be considered as a sole modality for early small primary tumor. It also has a role as an adjuvant to surgery in the setting of inadequate pathologically assessed resection margins, as does postoperative external beam radiotherapy ± chemotherapy, which is usually reserved for those with unfavorable pathological features. Brachytherapy can also be especially useful in the re-irradiation setting for persistent or recurrent disease or for a second primary arising within a previous radiation field. Biological agents targeting the epithelial growth factor receptor (EGFR) have emerged as a potential modality in combination with radiotherapy or chemoradiotherapy and are currently under

  7. Serial comprehensive geriatric assessment in elderly head and neck cancer patients undergoing curative radiotherapy identifies evolution of multidimensional health problems and is indicative of quality of life.

    Science.gov (United States)

    Pottel, L; Lycke, M; Boterberg, T; Pottel, H; Goethals, L; Duprez, F; Van Den Noortgate, N; De Neve, W; Rottey, S; Geldhof, K; Buyse, V; Kargar-Samani, K; Ghekiere, V; Debruyne, P R

    2014-05-01

    Head and neck (H&N) cancer is mainly a cancer of the elderly; however, the implementation of comprehensive geriatric assessment (CGA) to quantify functional age in these patients has not yet been studied. We evaluated the diagnostic performance of screening tools [Vulnerable Elders Survey-13 (VES-13), G8 and the Combined Screening Tool 'VES-13 + (17-G8)' or CST], the feasibility of serial CGA, and correlations with health-related quality of life evolution [HRQOL; European Organisation for Research and Treatment of Cancer Quality of Life Questionnaires (EORTC QLQ)-C30 and -HN35] during therapy in hundred patients, aged ≥65 years, with primary H&N cancer undergoing curative radio(chemo)therapy. Respectively 36.8%, 69.0%, 62.1% and 71.3% were defined vulnerable according to VES-13, G8, CST and CGA at week 0, mostly due to presence of severe grade co-morbidities, difficulties in community functioning and nutritional problems. At week 4, significantly more patients were identified vulnerable due to nutritional, functional and emotional deterioration. The CST did not achieve the predefined proportion necessary for validation. Vulnerable patients reported lower function and higher symptom HRQOL scores as compared with fit patients. A comparable deterioration in HRQOL was observed in both groups through therapy. In conclusion, G8 remains the screening tool of choice. Serial CGA identifies the evolution of multidimensional health problems and HRQOL conditions during therapy with potential to guide individualised supportive care. © 2014 John Wiley & Sons Ltd.

  8. Radiotherapy after radical prostatectomy: treatment recommendations differ between urologists and radiation oncologists.

    Directory of Open Access Journals (Sweden)

    Luke T Lavallée

    Full Text Available PURPOSE: There is no consensus on optimal use of radiotherapy following radical prostatectomy. The purpose of this study was to describe opinions of urologists and radiation oncologists regarding adjuvant and salvage radiotherapy following radical prostatectomy. METHODS: Urologists and genitourinary radiation oncologists were solicited to participate in an online survey. Respondent characteristics included demographics, training, practice setting, patient volume/experience, and access to radiotherapy. Participant practice patterns and attitudes towards use of adjuvant and salvage radiotherapy in standardized clinical scenarios were assessed. RESULTS: One hundred and forty-six staff physicians participated in the survey (104 urologists and 42 genitourinary radiation oncologists. Overall, high Gleason score (Gleason 7 vs. 6, RR 1.37 95% CI 1.19-1.56, p<0.0001 and Gleason 8-10 vs. 6, RR 1.56 95% CI 1.37-1.78, p<0.0001, positive surgical margin (RR 1.43 95% CI 1.26-1.62, p<0.0001, and extraprostatic tumour extension (RR 1.16 95% CI 1.05-1.28, p<0.002 conferred an increased probability of recommending adjuvant radiotherapy. Radiation oncologists were more likely to recommend adjuvant radiotherapy across all clinical scenarios (RR 1.48, 95% CI 1.39, 1.60, p <0.001. Major differences were found for patients with Gleason 6 and isolated positive surgical margin (radiotherapy selected by 21% of urologists vs. 70% of radiation oncologists, and patients with extraprostatic extension and negative surgical margins (radiotherapy selected by 18% of urologist vs. 57% of radiation oncologists. CONCLUSIONS: Urologists and radiation oncologists frequently disagree about recommendation for post-prostatectomy adjuvant radiotherapy. Since clinical equipoise exists between adjuvant versus early salvage post-operative radiotherapy, support of clinical trials comparing these approaches is strongly encouraged.

  9. Image-guided stereotactic ablative radiotherapy for the liver: a safe and effective treatment.

    Science.gov (United States)

    Van De Voorde, L; Vanneste, B; Houben, R; Damen, P; van den Bogaard, J; Lammering, G; Dejong, K; de Vos-Geelen, J; Buijsen, J; Öllers, M; Berbée, M; Lambin, P

    2015-02-01

    Stereotactic ablative body radiotherapy (SABR) is a non-invasive treatment option for inoperable patients or patients with irresectable liver tumors. Outcome and toxicity were evaluated retrospectively in this single-institution patient cohort. Between 2010 and 2014, 39 lesions were irradiated in 33 consecutive patients (18 male, 15 female, median age of 68 years). All the lesions were liver metastases (n = 34) or primary hepatocellular carcinomas (n = 5). The patients had undergone four-dimensional respiration-correlated PET-CT for treatment simulation to capture tumor motion. We analyzed local control with a focus on CT-based response at three months, one year and two years after treatment, looking at overall survival and the progression pattern. All patients were treated with hypofractionated image-guided stereotactic radiotherapy. The equivalent dose in 2 Gy fractions varied from 62.5 Gy to 150 Gy, delivered in 3-10 fractions (median dose 93.8 Gy, alpha/beta = 10). The CT-based regression pattern three months after radiotherapy revealed partial regression in 72.7% of patients with a complete remission in 27.3% of the cases. The site of first progression was predominantly distant. One- and two-year overall survival rates were 85.4% and 68.8%, respectively. No toxicity of grade 2 or higher according to the NCI Common Terminology Criteria for Adverse Events v4.0 was observed. SABR is a safe and efficient treatment for selected inoperable patients or irresectable tumors of the liver. Future studies should combine SABR with systemic treatment acting in synergy with radiation, such as immunological interventions or hypoxic cell radiosensitizers to prevent distant relapse. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Detecting depressive and anxiety disorders in distressed patients in primary care; comparative diagnostic accuracy of the Four-Dimensional Symptom Questionnaire (4DSQ and the Hospital Anxiety and Depression Scale (HADS

    Directory of Open Access Journals (Sweden)

    Verhaak Peter FM

    2009-08-01

    Full Text Available Abstract Background Depressive and anxiety disorders often go unrecognized in distressed primary care patients, despite the overtly psychosocial nature of their demand for help. This is especially problematic in more severe disorders needing specific treatment (e.g. antidepressant pharmacotherapy or specialized cognitive behavioural therapy. The use of a screening tool to detect (more severe depressive and anxiety disorders may be useful not to overlook such disorders. We examined the accuracy with which the Four-Dimensional Symptom Questionnaire (4DSQ and the Hospital Anxiety and Depression Scale (HADS are able to detect (more severe depressive and anxiety disorders in distressed patients, and which cut-off points should be used. Methods Seventy general practitioners (GPs included 295 patients on sick leave due to psychological problems. They excluded patients with recognized depressive or anxiety disorders. Patients completed the 4DSQ and HADS. Standardized diagnoses of DSM-IV defined depressive and anxiety disorders were established with the Composite International Diagnostic Interview (CIDI. Receiver Operating Characteristic (ROC analyses were performed to obtain sensitivity and specificity values for a range of scores, and area under the curve (AUC values as a measure of diagnostic accuracy. Results With respect to the detection of any depressive or anxiety disorder (180 patients, 61%, the 4DSQ and HADS scales yielded comparable results with AUC values between 0.745 and 0.815. Also with respect to the detection of moderate or severe depressive disorder, the 4DSQ and HADS depression scales performed comparably (AUC 0.780 and 0.739, p 0.165. With respect to the detection of panic disorder, agoraphobia and social phobia, the 4DSQ anxiety scale performed significantly better than the HADS anxiety scale (AUC 0.852 versus 0.757, p 0.001. The recommended cut-off points of both HADS scales appeared to be too low while those of the 4DSQ anxiety

  11. Adjuvant intensity-modulated proton therapy in malignant pleural mesothelioma. A comparison with intensity-modulated radiotherapy and a spot size variation assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lorentini, S. [Agenzia Provinciale per la Protonterapia (ATreP), Trento (Italy); Padova Univ. (Italy). Medical Physics School; Amichetti, M.; Fellin, F.; Schwarz, M. [Agenzia Provinciale per la Protonterapia (ATreP), Trento (Italy); Spiazzi, L. [Brescia Hospital (Italy). Medical Physics Dept.; Tonoli, S.; Magrini, S.M. [Brescia Hospital (Italy). Radiation Oncology Dept.

    2012-03-15

    Intensity-modulated radiation therapy (IMRT) is the state-of-the-art treatment for patients with malignant pleural mesothelioma (MPM). The goal of this work was to assess whether intensity-modulated proton therapy (IMPT) could further improve the dosimetric results allowed by IMRT. We re-planned 7 MPM cases using both photons and protons, by carrying out IMRT and IMPT plans. For both techniques, conventional dose comparisons and normal tissue complication probability (NTCP) analysis were performed. In 3 cases, additional IMPT plans were generated with different beam dimensions. IMPT allowed a slight improvement in target coverage and clear advantages in dose conformity (p < 0.001) and dose homogeneity (p = 0.01). Better organ at risk (OAR) sparing was obtained with IMPT, in particular for the liver (D{sub mean} reduction of 9.5 Gy, p = 0.001) and ipsilateral kidney (V{sub 20} reduction of 58%, p = 0.001), together with a very large reduction of mean dose for the contralateral lung (0.2 Gy vs 6.1 Gy, p = 0.0001). NTCP values for the liver showed a systematic superiority of IMPT with respect to IMRT for both the esophagus (average NTCP 14% vs. 30.5%) and the ipsilateral kidney (p = 0.001). Concerning plans obtained with different spot dimensions, a slight loss of target coverage was observed along with sigma increase, while maintaining OAR irradiation always under planning constraints. Results suggest that IMPT allows better OAR sparing with respect to IMRT, mainly for the liver, ipsilateral kidney, and contralateral lung. The use of a spot dimension larger than 3 x 3 mm (up to 9 x 9 mm) does not compromise dosimetric results and allows a shorter delivery time.

  12. Parotid gland function after radiotherapy

    NARCIS (Netherlands)

    Roesink, Judith Maria

    2005-01-01

    Radiotherapy is a common treatment for head and neck cancer patients. Unfortunately, it produces serious acute and long-term side effects to the oral cavity. One severe complication is the loss of salivary gland function, which can persists for many years. Saliva has multiple functions relating to

  13. [Bullous lichen sclerosus after radiotherapy].

    Science.gov (United States)

    Tournillac, I; Dandurand, M; Guillot, B

    1998-02-01

    Bullous lichen sclerosus is an uncommon observation after radiotherapy and can be misdiagnosed as a radiodermitis or recurrence of the neoplasia. Two women developed bullous lichen sclerosus after radiotherapy. The delay after radiotherapy was 4 months and 10 years respectively. Irradiation dose was 60 and 64 grays. The lesions covered more than the irradiated zone in one case. Stabilization or regression of the lesions was obtained with cases I topical corticosteroids, with acitretine in one case. These cases, and similar cases reported in the literature, underline the fact that the condition has only been reported in women. This is probably because of the nature of the neoplasias treated (breast cancer in 20 cases and cervical cancer in 1). The delay to onset of the skin lesions are quite variable. Lichen sclerosus or morphea may be observed in the irradiated zone but may also appear at a distance. These lesions are not associated with recurrence of the initial cancer. As no association between breast cancer and localized sclerodermia has been found, the causal role is probably played by radiotherapy, producing a Koebner phenomena in predisposed tissue.

  14. Thalassaemic osteoarthropathy treated with radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Davies, A.N. (King' s Coll. Hospital, London (United Kingdom))

    1993-11-01

    Patients with beta thalassaemia may develop a specific osteoarthropathy involving the feet. A number of different treatments for this condition have been tried, including rest, analgesia and hypertransfusion. We report a case of a patient with thalassaemic osteoarthropathy who responded to radiotherapy after failing conventional treatment. (author).

  15. Oral complications of cancer radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dreizen, S.; Daly, T.E.; Drane, J.B.; Brown, L.R.

    1977-02-01

    Injury to surrounding tissues during radiotherapy for oral cancer can have devastating physical and psychologic consequences for the patient. Oral complications include xerostomia, dental decay, mucositis, taste loss, osteoradionecrosis, infection, and trismus. In many instances, these problems can be eradicated or controlled with appropriate treatment.

  16. [Radiotherapy for primary lung carcinoma].

    Science.gov (United States)

    Giraud, P; Lacornerie, T; Mornex, F

    2016-09-01

    Indication, doses, technique of radiotherapy and concomitant chemotherapy, for primary lung carcinoma are presented. The recommendations for delineation of the target volumes and organs at risk are detailed. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  17. Quantitative assessment of inter-observer variability in target volume delineation on stereotactic radiotherapy treatment for pituitary adenoma and meningioma near optic tract

    Directory of Open Access Journals (Sweden)

    Aibe Norihiro

    2011-01-01

    Full Text Available Abstract Background To assess inter-observer variability in delineating target volume and organs at risk in benign tumor adjacent to optic tract as a quality assurance exercise. Methods We quantitatively analyzed 21 plans made by 11 clinicians in seven CyberKnife centers. The clinicians were provided with a raw data set (pituitary adenoma and meningioma including clinical information, and were asked to delineate the lesions and create a treatment plan. Their contouring and plans (10 adenoma and 11 meningioma plans, were then compared. In addition, we estimated the influence of differences in contouring by superimposing the respective contours onto a default plan. Results The median planning target volume (PTV and the ratio of the largest to the smallest contoured volume were 9.22 cm3 (range, 7.17 - 14.3 cm3 and 1.99 for pituitary adenoma, and 6.86 cm3 (range 6.05 - 14.6 cm3 and 2.41 for meningioma. PTV volume was 10.1 ± 1.74 cm3 for group 1 with a margin of 1 -2 mm around the CTV (n = 3 and 9.28 ± 1.8 cm3(p = 0.51 for group 2 with no margin (n = 7 in pituitary adenoma. In meningioma, group 1 showed larger PTV volume (10.1 ± 3.26 cm3 than group 2 (6.91 ± 0.7 cm3, p = 0.03. All submitted plan keep the irradiated dose to optic tract within the range of 50 Gy (equivalent total doses in 2 Gy fractionation. However, contours superimposed onto the dose distribution of the default plan indicated that an excessive dose 23.64 Gy (up to 268% of the default plan in pituitary adenoma and 24.84 Gy (131% of the default plan in meningioma to the optic nerve in the contours from different contouring. Conclusion Quality assurance revealed inter-observer variability in contour delineation and their influences on planning for pituitary adenoma and meningioma near optic tract.

  18. A Monte-Carlo study to assess the effect of 1.5 T magnetic fields on the overall robustness of pencil-beam scanning proton radiotherapy plans for prostate cancer

    Science.gov (United States)

    Kurz, Christopher; Landry, Guillaume; Resch, Andreas F.; Dedes, George; Kamp, Florian; Ganswindt, Ute; Belka, Claus; Raaymakers, Bas W.; Parodi, Katia

    2017-11-01

    Combining magnetic-resonance imaging (MRI) and proton therapy (PT) using pencil-beam scanning (PBS) may improve image-guided radiotherapy. We aimed at assessing the impact of a magnetic field on PBS-PT plan quality and robustness. Specifically, the robustness against anatomical changes and positioning errors in an MRI-guided scenario with a 30 cm radius 1.5 T magnetic field was studied for prostate PT. Five prostate cancer patients with three consecutive CT images (CT1-3) were considered. Single-field uniform dose PBS-PT plans were generated on the segmented CT1 with Monte-Carlo-based treatment planning software for inverse optimization. Plans were optimized at 90° gantry angle without B-field (no B), with  ±1.5 T B-field (B and minus B), as well as at 81° gantry angle and  +1.5 T (B G81). Plans were re-calculated on aligned CT2 and CT3 to study the impact of anatomical changes. Dose distributions were compared in terms of changes in DVH parameters, proton range and gamma-index pass-rates. To assess the impact of positioning errors, DVH parameters were compared for  ±5 mm CT1 patient shifts in anterior–posterior (AP) and left–right (LR) direction. Proton beam deflection considerably reduced robustness against inter-fractional changes for the B scenario. Range agreement, gamma-index pass-rates and PTV V95% were significantly lower compared to no B. Improved robustness was obtained for minus B and B G81, the latter showing only minor differences to no B. The magnetic field introduced slight dosimetric changes under LR shifts. The impact of AP shifts was considerably larger, and equivalent for scenarios with and without B-field. Results suggest that robustness equivalent to PT without magnetic field can be achieved by adaptation of the treatment parameters, such as B-field orientation (minus B) with respect to the patient and/or gantry angle (B G81). MRI-guided PT for prostate cancer might thus be implemented without compromising robustness

  19. In vivo dosimetry in external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mijnheer, Ben [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam 1066 CX (Netherlands); Beddar, Sam [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Izewska, Joanna [Division of Human Health, International Atomic Energy Agency, Vienna 1400 (Austria); Reft, Chester [Department of Radiation and Cellular Oncology, University of Chicago Medical Center, Chicago, Illinois 60637 (United States)

    2013-07-15

    In vivo dosimetry (IVD) is in use in external beam radiotherapy (EBRT) to detect major errors, to assess clinically relevant differences between planned and delivered dose, to record dose received by individual patients, and to fulfill legal requirements. After discussing briefly the main characteristics of the most commonly applied IVD systems, the clinical experience of IVD during EBRT will be summarized. Advancement of the traditional aspects of in vivo dosimetry as well as the development of currently available and newly emerging noninterventional technologies are required for large-scale implementation of IVD in EBRT. These new technologies include the development of electronic portal imaging devices for 2D and 3D patient dosimetry during advanced treatment techniques, such as IMRT and VMAT, and the use of IVD in proton and ion radiotherapy by measuring the decay of radiation-induced radionuclides. In the final analysis, we will show in this Vision 20/20 paper that in addition to regulatory compliance and reimbursement issues, the rationale for in vivo measurements is to provide an accurate and independent verification of the overall treatment procedure. It will enable the identification of potential errors in dose calculation, data transfer, dose delivery, patient setup, and changes in patient anatomy. It is the authors' opinion that all treatments with curative intent should be verified through in vivo dose measurements in combination with pretreatment checks.

  20. Epicondylopathia humeri. Indication, technique and clinical results of radiotherapy; Epicondylopathia humeri. Indikation, Technik, klinische Ergebnisse der Radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Seegenschmiedt, M.H. [Strahlentherapeutische Klinik und Poliklinik, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany)]|[Klinik fuer Radioonkologie, Strahlentherapie und Nuklearmedizin, Alfred-Krupp von Bohlen und Halbach-Krankenhaus, Essen (Germany); Keilholz, L. [Strahlentherapeutische Klinik und Poliklinik, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany); Martus, P. [Inst. fuer Medizinische Statistik und Dokumentation, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany); Kuhr, M. [Orthopaedische Klinik, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany); Wichmann, G. [Strahlentherapeutische Klinik und Poliklinik, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany); Sauer, R. [Strahlentherapeutische Klinik und Poliklinik, Waldkrankenhaus St. Marien, Erlangen-Nuernberg Univ., Erlangen (Germany)

    1997-04-01

    Background: The efficacy of radiotherapy for degenerative-inflammatory disorders is well known, but so far long-term observations and reliable assessment of symptoms according to objective criteria and scores for validation are still missing. Results: Forty-three patients (ot totally 85)(50 elbows of totally 93) achieved `complete pain relief (CR)` in all pain categories: 59% elbows with pain at strain had `complete pain relief`, 79% with pain at night, 84% with permanent pain, 80% with pain at rest and 81% with pain at initiation or morning stiffness. Nineteen elbows gained `major pain relief (PR)`, i.e. had minor symptoms (maximum grade 1) in all categories. Thus, a total of 69 (74%) elbows responded to radiotherapy. Seventeen patients (19 elbows) were operated because of persistent symptoms or dissatisfaction in long-term follow-up; 7 of those became completely free of symptoms. The Morrey-Score improved by a mean of 18 points from 78 prior to radiotherapy to 96 points at last follow-up. According to the Morrey-Score only 2 patients became worse in long-term follow-up. Two parameters indicated a negative prognosis in multivariate analysis: Long symptom duration prior to radiotherapy and immobilisation with plaster (p<0.05). Conclusions: Radiotherapy for refractory epicondylopathia humeri is highly effective. Long symptom duration and long-term immobilisation by plaster are negative prognostic factors for treatment outcome. Due to the low side effects and treatment costs, radiotherapy is a good therapeutic option in comparison to conventional treatment methods and surgery in the chronic stage of epicondylopathia humeri. (orig./VHE) [Deutsch] Hintergrund: Die Wirksamkeit der Radiotherapie bei degenerativ-entzuendlichen Erkrankungen ist klinisch zwar gut belegt, doch fehlen ausreichende Langzeitbeobachtungen und eine Bewertung nach objektivierbaren Kriterien zur Validierung. Ergebnis: 43 Patienten (von insgesamt 85)(50 Ellenbogen von insgesamt 93) wurden in allen

  1. Psychological and immunological characteristics of fatigued women undergoing radiotherapy for early-stage breast cancer.

    Science.gov (United States)

    Courtier, Nicholas; Gambling, Tina; Enright, Stephanie; Barrett-Lee, Peter; Abraham, Jacinta; Mason, Malcolm D

    2013-01-01

    The amelioration of fatigue in radiotherapy patients is limited by an equivocal aetiology and uncertainty regarding who is likely to experience significant fatigue. The research objective was to characterise fatigue in women undergoing radiotherapy for breast cancer, in order to evaluate associations with elevations in anxiety, depression and a marker of systemic inflammation. Participants comprised 100 women, diagnosed with stages 0-IIA breast cancer and prescribed with 40 Gy in 15 fractions over 3 weeks. Fatigue was assessed at baseline between 10 and 22 days before radiotherapy, after 10 and 15 fractions of radiotherapy and 4 weeks after the completion of radiotherapy, using the Functional Assessment of Chronic Illness Therapy Fatigue Subscale. Psychological status was self-reported using the Hospital Anxiety and Depression Scale. Sera concentrations of interleukin-6-soluble receptor were established via enzyme-linked immunosorbent assay. The contributions of pretreatment factors to fatigue were analysed using multivariable regression. Thirty-eight percent of participants experienced significant fatigue during radiotherapy, with the remainder little are affected. After controlling for baseline fatigue, anxiety before treatment was the strongest unique predictor of subsequent fatigue. During radiotherapy, interleukin-6-soluble receptor was significantly elevated in the fatigued group compared to the non-fatigued group (p = 0.01). This association was not mediated by depression. The data are consistent with the concept that psychological distress prior to radiotherapy relates to a distinct immunological and behavioural response during radiotherapy. Patients reporting elevated anxiety should benefit from interventions that appropriately address the underlying psychological distress and have the potential to ameliorate disabling treatment-related fatigue.

  2. Disturbed Intracardiac Flow Organization After Atrioventricular Septal Defect Correction as Assessed With 4D Flow Magnetic Resonance Imaging and Quantitative Particle Tracing

    NARCIS (Netherlands)

    Calkoen, Emmeline E.; de Koning, Patrick J. H.; Blom, Nico A.; Kroft, Lucia J. M.; de Roos, Albert; Wolterbeek, Ron; Roest, Arno A. W.; Westenberg, Jos J. M.

    2015-01-01

    Objectives Four-dimensional (3 spatial directions and time) velocity-encoded flow magnetic resonance imaging with quantitative particle tracing analysis allows assessment of left ventricular (LV) blood flow organization. Corrected atrioventricular septal defect (AVSD) patients have an abnormal left

  3. Image quality assessment of a 1.5T dedicated magnetic resonance-simulator for radiotherapy with a flexible radio frequency coil setting using the standard American College of Radiology magnetic resonance imaging phantom test

    Science.gov (United States)

    Wong, Oi Lei; Yu, Siu Ki; Cheung, Kin Yin

    2017-01-01

    Background A flexible RF coil setting has to be used on an MR-simulator (MR-sim) in the head and neck simulation scan for radiotherapy (RT) purpose, while the image quality might be compromised due to the sub-optimized flexible coil compared to the normal diagnostic radiological (DR) head coil. In this study, we assessed the image quality of an MR-sim by conducting the standard American College of Radiology (ACR) MRI phantom test on a 1.5T MR-sim under RT-setting and comparing it to DR-setting. Methods A large ACR MRI phantom was carefully positioned, aligned and scanned 9 times for each under RT- and DR-setting on a 1.5T MR-sim, following the ACR scanning instruction. Images were analyzed following the ACR guidance. Measurement results under two coil settings were quantitatively compared. Inter-observer disagreements under RT-setting between two physicists were compared using Bland-Altman (BA) analysis and intra-class correlation coefficient (ICC). Results The MR-sim with RT-setting obtained sufficiently good image quality to pass all ACR recommended criteria. No significant difference was found in phantom length accuracy, high-contrast spatial resolution, slice thickness accuracy, slice position accuracy, and percent-signal ghosting. RT-setting significantly under-performed in low-contrast object detectability, while better performed in image intensity uniformity. BA analysis showed that 95% limit of agreement and biases of phantom test measurement under RT-setting between two observers were very small. Excellent inter-observer agreement (ICC >0.75) was achieved in all measurements except for slice thickness accuracy (ICC =0.42, moderate agreement) under RT-setting. Conclusions Very good and highly reproducible image quality could be achieved on a 1.5T MR-sim with a flexible coil setting as revealed by the standard ACR MRI phantom test. The flexible RT-setting compromised in image signal-to-noise ratio (SNR) compared to the normal DR-setting, and resulted in

  4. Image quality assessment of a 1.5T dedicated magnetic resonance-simulator for radiotherapy with a flexible radio frequency coil setting using the standard American College of Radiology magnetic resonance imaging phantom test.

    Science.gov (United States)

    Wong, Oi Lei; Yuan, Jing; Yu, Siu Ki; Cheung, Kin Yin

    2017-04-01

    A flexible RF coil setting has to be used on an MR-simulator (MR-sim) in the head and neck simulation scan for radiotherapy (RT) purpose, while the image quality might be compromised due to the sub-optimized flexible coil compared to the normal diagnostic radiological (DR) head coil. In this study, we assessed the image quality of an MR-sim by conducting the standard American College of Radiology (ACR) MRI phantom test on a 1.5T MR-sim under RT-setting and comparing it to DR-setting. A large ACR MRI phantom was carefully positioned, aligned and scanned 9 times for each under RT- and DR-setting on a 1.5T MR-sim, following the ACR scanning instruction. Images were analyzed following the ACR guidance. Measurement results under two coil settings were quantitatively compared. Inter-observer disagreements under RT-setting between two physicists were compared using Bland-Altman (BA) analysis and intra-class correlation coefficient (ICC). The MR-sim with RT-setting obtained sufficiently good image quality to pass all ACR recommended criteria. No significant difference was found in phantom length accuracy, high-contrast spatial resolution, slice thickness accuracy, slice position accuracy, and percent-signal ghosting. RT-setting significantly under-performed in low-contrast object detectability, while better performed in image intensity uniformity. BA analysis showed that 95% limit of agreement and biases of phantom test measurement under RT-setting between two observers were very small. Excellent inter-observer agreement (ICC >0.75) was achieved in all measurements except for slice thickness accuracy (ICC =0.42, moderate agreement) under RT-setting. Very good and highly reproducible image quality could be achieved on a 1.5T MR-sim with a flexible coil setting as revealed by the standard ACR MRI phantom test. The flexible RT-setting compromised in image signal-to-noise ratio (SNR) compared to the normal DR-setting, and resulted in reduced low-contrast object detectability.

  5. Radiotherapy-induced thyroid disorders.

    Science.gov (United States)

    Jereczek-Fossa, Barbara A; Alterio, Daniela; Jassem, Jacek; Gibelli, Bianca; Tradati, Nicoletta; Orecchia, Roberto

    2004-06-01

    Despite their specific functional consequences, radiotherapy-induced thyroid abnormalities remain under-estimated and underreported. These sequelae may include primary or central hypothyroidism, thyroiditis, Graves' disease, euthyroid Graves' ophthalmopathy, benign adenomas, multinodular goitre and radiation-induced thyroid carcinoma. Primary hypothyroidism, the most common radiation-induced thyroid dysfunction, affects 20-30% of patients administered following curative radiotherapy to the neck region, with approximately half of the events occurring within the first 5 years after therapy. The relative risk of radiation-induced cancer (mainly well-differentiated tumours) is 15-53-fold higher than in non-irradiated population. The aetiology of radiation-induced thyroid injury includes vascular damage, parenchymal cell damage and auto-immune reactions. Total radiotherapy dose, irradiated volume of the thyroid gland, and the extent of prior thyroid resection are among the most important factors associated with the risk of hypothyroidism. The contribution of other treatment modalities (chemotherapy, endocrine therapy) as well as patient- and tumour-related factors is less clear. Reduction in radiation dose to the thyroid gland and hypothalamic/pituitary complex should be attempted whenever possible. New radiotherapy techniques, such as stereotactic radiosurgery, three-dimensional conformal irradiation, intensity modulated radiotherapy and proton therapy allow generally better dose distribution with lower dose to the non-target organs. The diagnostic approach to thyroid radiation injury includes baseline thyroid function assays in all patients undergoing thyroid or parasellar irradiation. Recommended follow-up procedures include at least annual evaluation with a history for symptoms of thyroid dysfunction, clinical examination, and measurement of thyroid hormones and thyrotropin. Management of overt hypothyroidism is based on hormone replacement therapy. Thyroid hormone

  6. National arrangements for radiotherapy; Mesures nationales pour la radiotherapie. Travail collectif des missions

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    After a presentation of several letters exchanged between the French health ministry and public agencies in charge of public health or nuclear safety after a radiotherapy accident in Epinal, this report comments the evolution of needs in cancerology care and the place given to radiotherapy. It outlines the technological and organisational evolution of radiotherapy and presents the distribution of radiotherapy equipment, of radio-therapists and other radiotherapy professionals in France. Within the context of radiotherapy accidents which occurred in 2007, it presents the regulatory arrangements which aimed at improving the safety, short term and middle term arrangements which are needed to support and structure radiotherapy practice quality. It stresses the fact that the system will deeply evolve by implementing a radiotherapy vigilance arrangement and a permanent follow-on and adaptation plan based on surveys and the creation of a national committee.

  7. Functional Image-Guided Radiotherapy Planning in Respiratory-Gated Intensity-Modulated Radiotherapy for Lung Cancer Patients With Chronic Obstructive Pulmonary Disease

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Tomoki, E-mail: tkkimura@hiroshima-u.ac.jp [Department of Radiation Oncology, Hiroshima University, Graduate School of Biomedical Sciences, Hiroshima City (Japan); Nishibuchi, Ikuno; Murakami, Yuji; Kenjo, Masahiro; Kaneyasu, Yuko; Nagata, Yasushi [Department of Radiation Oncology, Hiroshima University, Graduate School of Biomedical Sciences, Hiroshima City (Japan)

    2012-03-15

    Purpose: To investigate the incorporation of functional lung image-derived low attenuation area (LAA) based on four-dimensional computed tomography (4D-CT) into respiratory-gated intensity-modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT) in treatment planning for lung cancer patients with chronic obstructive pulmonary disease (COPD). Methods and Materials: Eight lung cancer patients with COPD were the subjects of this study. LAA was generated from 4D-CT data sets according to CT values of less than than -860 Hounsfield units (HU) as a threshold. The functional lung image was defined as the area where LAA was excluded from the image of the total lung. Two respiratory-gated radiotherapy plans (70 Gy/35 fractions) were designed and compared in each patient as follows: Plan A was an anatomical IMRT or VMAT plan based on the total lung; Plan F was a functional IMRT or VMAT plan based on the functional lung. Dosimetric parameters (percentage of total lung volume irradiated with {>=}20 Gy [V20], and mean dose of total lung [MLD]) of the two plans were compared. Results: V20 was lower in Plan F than in Plan A (mean 1.5%, p = 0.025 in IMRT, mean 1.6%, p = 0.044 in VMAT) achieved by a reduction in MLD (mean 0.23 Gy, p = 0.083 in IMRT, mean 0.5 Gy, p = 0.042 in VMAT). No differences were noted in target volume coverage and organ-at-risk doses. Conclusions: Functional IGRT planning based on LAA in respiratory-guided IMRT or VMAT appears to be effective in preserving a functional lung in lung cancer patients with COPD.

  8. Pediatric radiotherapy planning and treatment

    CERN Document Server

    Olch, Arthur J

    2013-01-01

    "This is a very well-written and -organized book covering the planning and delivery aspects unique to pediatric radiotherapy. The author is a respected and well-known medical physicist with extensive pediatric radiotherapy experience. … a very useful book for any clinical physicist treating pediatric cases and seeking contextual and historical perspective. … a great reference for medical physicists who may not see many pediatric cases and can look to this text as a one-stop shop for not only a comprehensive overview, but detailed explanation for specific pediatric disease sites. Overall, it is a great addition to the reference library of any radiation therapy physicist."-Medical Physics, April 2014.

  9. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G. [Department of Physics of the University and INFN, Milan (Italy)]. e-mail: grazia.gambarini@mi.infn.it

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  10. Proton Radiotherapy for Pediatric Sarcoma

    Directory of Open Access Journals (Sweden)

    Matthew M. Ladra

    2014-01-01

    Full Text Available Pediatric sarcomas represent a distinct group of pathologies, with approximately 900 new cases per year in the United States alone. Radiotherapy plays an integral role in the local control of these tumors, which often arise adjacent to critical structures and growing organs. The physical properties of proton beam radiotherapy provide a distinct advantage over standard photon radiation by eliminating excess dose deposited beyond the target volume, thereby reducing both the dose of radiation delivered to non-target structures as well as the total radiation dose delivered to a patient. Dosimetric studies comparing proton plans to IMRT and 3D conformal radiation have demonstrated the superiority of protons in numerous pediatric malignancies and data on long-term clinical outcomes and toxicity is emerging. In this article, we review the existing clinical and dosimetric data regarding the use of proton beam radiation in malignant bone and soft tissue sarcomas.

  11. Radiotherapy for metastatic fibrolamellar hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Justin G. Peacock

    2013-07-01

    Full Text Available Fibrolamellar hepatocellular carcinoma (FLHCC is a rare variant of hepatocellular carcinoma (HCC that commonly affects young individuals without a prior history of liver disease. FLHCC commonly results in a better prognosis than HCC; however, the risk of recurrence and metastatic disease is high. FLHCC is typically treated by primary resection of the tumor with 50-75% cure rates. The use of radiation therapy in FLHCC has not been assessed on its own, and may show some success in a very few reported combination therapy cases. We report on the successful use of radiation therapy in a case of metastatic FLHCC to the lung following primary and secondary resections. Our treatment of the large, metastatic, pulmonary FLHCC tumor with 40 Gy in 10 fractions resulted in an 85.9% tumor volume decrease over six months. This suggests FLHCC may be a radiosensitive tumor and radiotherapy may be valuable in unresectable or metastatic tumors.

  12. Technological advances in radiotherapy of rectal cancer

    DEFF Research Database (Denmark)

    Appelt, Ane L; Sebag-Montefiore, David

    2016-01-01

    PURPOSE OF REVIEW: This review summarizes the available evidence for the use of modern radiotherapy techniques for chemoradiotherapy for rectal cancer, with specific focus on intensity-modulated radiotherapy (IMRT) and volumetric arc therapy (VMAT) techniques. RECENT FINDINGS: The dosimetric....... Overall results are encouraging, as toxicity levels - although varying across reports - appear lower than for 3D conformal radiotherapy. Innovative treatment techniques and strategies which may be facilitated by the use of IMRT/VMAT include simultaneously integrated tumour boost, adaptive treatment...

  13. Inflammatory Skin Conditions Associated With Radiotherapy.

    Science.gov (United States)

    Hernández Aragüés, I; Pulido Pérez, A; Suárez Fernández, R

    2017-04-01

    Radiotherapy for cancer is used increasingly. Because skin cells undergo rapid turnover, the ionizing radiation of radiotherapy has collateral effects that are often expressed in inflammatory reactions. Some of these reactions-radiodermatitis and recall phenomenon, for example-are very familiar to dermatologists. Other, less common radiotherapy-associated skin conditions are often underdiagnosed but must also be recognized. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. [Stereotactic radiotherapy for prostate cancer].

    Science.gov (United States)

    Quero, L; Hennequin, C

    2014-01-01

    Stereotactic radiotherapy is a new option in the treatment of prostate cancer. However, only retrospective series and a few prospective phase II trials are available at this moment, including a few thousands of patients with a short follow-up. Most of the protocols delivered 33 to 38 Gy in four or five fractions. Acute toxicity seems to be similar to the one observed after conventional radiotherapy. Late toxicity is less evaluable because of the short follow-up: the rate of radiation-induced proctitis seems low in the published series. Urinary toxicities are not properly evaluated: some series reported a high incidence of urinary complications grade or higher. Most of the patients belong to the D'Amico's favourable group: biochemical controls are equivalent to those observed after conventional irradiation, but the follow-up is often shorter than 5 years and no definitive conclusion could be made about the efficiency of the technique. Data for the intermediate and high risk groups are not mature. In conclusion, stereotactic radiotherapy could strongly modified the management of prostate cancer: some phase III trials have started to confirm the good results reported in preliminary series. Copyright © 2014. Published by Elsevier SAS.

  15. Radiotherapy for diffuse brainstem glioma in children and young adults.

    Science.gov (United States)

    Hu, Xin; Fang, Yuan; Hui, Xuhui; Jv, Yan; You, Chao

    2016-06-27

    Diffuse brainstem glioma is a devastating disease with very poor prognosis. The most commonly used radiological treatment is conventional fractionated radiation. So far, there is no meta-analysis or systematic review available that assesses the benefits or harms of radiation in people with diffuse brainstem glioma. To assess the effects of conventional fractionated radiotherapy (with or without chemotherapy) versus other therapies (including different radiotherapy techniques) for newly diagnosed diffuse brainstem gliomas in children and young adults aged 0 to 21 years. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE/PubMed, and EMBASE to 19 August 2015. We scanned conference proceedings from the International Society for Paediatric Oncology (SIOP), International Symposium on Paediatric Neuro-Oncology (ISPNO), Society of Neuro-Oncology (SNO), and European Association of Neuro-Oncology (EANO) from 1 January 2010 to 19 August 2015. We searched trial registers including the International Standard Randomised Controlled Trial Number (ISRCTN) Register, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), and the register of the National Institutes of Health to 19 August 2015. We imposed no language restrictions. All randomised controlled trials (RCTs), quasi-randomised trials (QRCTs), or controlled clinical trials (CCTs) that compared conventional fractionated radiotherapy (with or without chemotherapy) versus other therapies (including different radiotherapy techniques) for newly diagnosed diffuse brainstem glioma in children and young adults aged 0 to 21 years. Two review authors independently screened studies for inclusion, extracted data, assessed the risk of bias in each eligible trial, and conducted GRADE assessment of included studies. We resolved disagreements through discussion. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of

  16. Risk-adapted targeted intraoperative radiotherapy versus whole-breast radiotherapy for breast cancer

    DEFF Research Database (Denmark)

    Vaidya, Jayant S; Wenz, Frederik; Bulsara, Max

    2014-01-01

    The TARGIT-A trial compared risk-adapted radiotherapy using single-dose targeted intraoperative radiotherapy (TARGIT) versus fractionated external beam radiotherapy (EBRT) for breast cancer. We report 5-year results for local recurrence and the first analysis of overall survival....

  17. Feasibility of spacers to facilitate postoperative radiotherapy for retroperitoneal sarcomas.

    Science.gov (United States)

    Reid, Jessica; Smith, Richard; Borg, Martin; Dobbins, Christopher; Gowda, Raghu; Chryssidis, Steve; Borg, Matthew; Neuhaus, Susan

    2017-12-01

    The role and timing of postoperative radiotherapy (PORT) in the management of retroperitoneal sarcoma (RPS) remains controversial. This is a retrospective cohort review of patients undergoing curative resection for RPS at a single institution between January 2011 and July 2016. Patient selection was through the South Australian Soft Tissue Tumour Multidisciplinary Group (MDT) based at Royal Adelaide Hospital. An individualised approach, including assessment of resectability, histopathological grade and subtype, and radiotherapy considerations, was taken for each patient. Patients offered preoperative radiotherapy or palliation were excluded. A saline-filled spacer was inserted following operative resection. Radiotherapy commenced postoperatively. Patients underwent laparotomy to remove the device approximately 6 weeks post completion of PORT. Primary endpoints were technical feasibility, perioperative morbidity and radiation toxicity. Secondary endpoints were local recurrence (LR), distant recurrence (DR) and death. During the study period, 40 patients with RPS were managed through the MDT. Twelve patients (ages 33-78) underwent PORT utilising spacers. Radiotherapy toxicity was reported in four patients and extensive adhesions observed in another four patients during spacer removal. Median follow-up was 35 months (range 4-60). Seven patients remain alive and disease free. Four patients developed LR, three developed DR. Three patients died; two with DR and one with LR. Two patients with recurrent/progressive disease are alive; one with DR and one with LR. Use of intraoperative spacers to facilitate PORT is feasible, with acceptable toxicity following resection of RPS. Patient selection for this approach remains to be determined. © 2017 The Royal Australian and New Zealand College of Radiologists.

  18. Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

    Science.gov (United States)

    M. Noor, Noramaliza; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D. A.

    2017-11-01

    Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 μm core diameter Ge-doped silica fibres (Ge-9 μm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%.

  19. Vaginal dilator therapy for women receiving pelvic radiotherapy

    Science.gov (United States)

    Miles, Tracie; Johnson, Nick

    2014-01-01

    Background Many vaginal dilator therapy guidelines advocate routine vaginal dilation during and after pelvic radiotherapy to prevent stenosis (abnormal narrowing of the vagina). The UK Gynaecological Oncology Nurse Forum recommend dilation “three times weekly for an indefinite time period”. The UK patient charity Cancer Backup advises using vaginal dilators from two to eight weeks after the end of radiotherapy treatment. Australian guidelines recommend dilation after brachytherapy “as soon as is comfortably possible” and “certainly within four weeks and to continue for three years or indefinitely if possible”. However, dilation is intrusive, uses health resources and can be psychologically distressing. It has also caused rare but very serious damage to the rectum. Objectives To review the benefits and harms of vaginal dilation therapy associated with pelvic radiotherapy for cancer. Search methods Searches included the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 4), MEDLINE (1950 to 2008), EMBASE (1980 to 2008) and CINAHL (1982 to 2008). Selection criteria Any comparative randomised controlled trials (RCT) or data of any type which compared dilation or penetration of the vagina after pelvic radiotherapy treatment for cancer. Data collection and analysis The review authors independently abstracted data and assessed risk of bias. We analysed the mean difference in sexual function scores and the risk ratio for non-compliance at six weeks and three months in single trial analyses. No trials met the inclusion criteria. Main results Dilation during or immediately after radiotherapy can, in rare cases, cause damage and there is no persuasive evidence from any study to demonstrate that it prevents stenosis. Data from one RCT showed no improvement in sexual scores in women who were encouraged to practice dilation. Two case series and one comparative study using historical controls suggest that dilation might be

  20. Role of radiotherapy in hospice care

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Tetsuo; Sugiyama, Akira; Shimizu, Teppei; Ichinohe, Kenji; Teshima, Takeshi; Kaneko, Masao; Hara, Yoshio; Chihara, Satoshi.

    1989-01-01

    The aim of palliative radiotherapy for the terminally ill is to improve the quality of the remaining span of life. From November 1982 to September 1987, 69 patients in the Seirei Hospice have been treated with such radiotherapy, and symptomatic relief was obtained in 64% of these patients. Radiotherapy also proved useful in achieving an improvement in their performance status. While the aim of hospice care is not directed towards treatment of the underlying disease, the use of radiotherapy is considered to have an important role in hospice care.

  1. Endobiliary Stent Position Changes during External-beam Radiotherapy

    OpenAIRE

    Chu, Kwun-Ye; Eccles, Cynthia L.; Brunner, Thomas B.

    2015-01-01

    Purpose Endobiliary stents can be used as surrogates for pancreatic localization when using cone-beam computed tomography (CBCT) during external-beam radiotherapy (EBRT). This work reports on interfraction stent position changes during EBRT for locally advanced pancreatic cancer (LAPC). Materials and Methods Six patients with endobiliary stents who underwent EBRT for LAPC were assessed. Measurements from the most superior aspect of the stent (sup stent) and the most inferior aspect of the ste...

  2. Spine Stereotactic Body Radiotherapy: Indications, Outcomes, and Points of Caution

    OpenAIRE

    Tseng, Chia-Lin; Eppinga, Wietse; Charest-Morin, Raphaele; Soliman, Hany; Myrehaug, Sten; Maralani, Pejman Jabehdar; Campbell, Mikki; Lee, Young K.; Fisher, Charles; Michael G Fehlings; Chang, Eric L; Lo, Simon S; Sahgal, Arjun

    2017-01-01

    Study Design: A broad narrative review. Objectives: The objective of this article is to provide a technical review of spine stereotactic body radiotherapy (SBRT) planning and delivery, indications for treatment, outcomes, complications, and the challenges of response assessment. The surgical approach to spinal metastases is discussed with an overview of emerging minimally invasive techniques. Methods: A comprehensive review of the literature was conducted on the techniques, outcomes, and deve...

  3. Postoperative radiotherapy in N0 laryngeal cancer; Radiotherapie postoperatoire des cancers larynges classes N0

    Energy Technology Data Exchange (ETDEWEB)

    Maillard, S.; Cauchois, A.; Froissart, D.; Nguyen, T.D. [Institut Jean-Godinot, Service de radiotherapie, 51 - Reims (France); Jovenin, N. [Centre Hospitalier Universitaire, DIM, 51 - Reims (France); Merol, J.C.; Chays, A. [Centre Hospitalier Universitaire, Service d' otorhinolaryngologie, 51 - Reims (France)

    2005-09-15

    Purpose. - A retrospective study to re-assess the indications for postoperative radiation therapy in squamous cell carcinoma of the larynx staged N0 after gross resection. Patients and methods. - Between January 1975 and December 2000, 166 patients with squamous cell carcinoma of the larynx were treated by total laryngectomy with or without neck dissection. Surgery was completed by external radiotherapy delivering 45 to 65 Gy to the tumour bed and 45 to 50 Gy to cervical lymphatic chains. Minimal follow-up was 36 months and median follow-up was 98 months. Results. - The rate of nodal recurrence was 6% (median time for relapse was 9 months). The survival rates at 1. 2, 3 and 5 years were 93.5, 84, 80 and 69% respectively, with a 8 year 3 month median survival. The univariate analysis showed 4 parameters, which significantly increased the risk of local recurrence: the medical necessity for immediate tracheotomy, the sub-glottic involvement, the involvement of the whole larynx and the presence of lymphatic emboli in the neck dissection. There was no statistically significant difference between the patients with or without a neck dissection. Fifty-nine secondary cancers were observed, 15 of them occurring in the head and neck area. The Late complications consisted of cervical subcutaneous fibrosis (7%), oesophageal stricture (4%), oeso-tracheal fistula (1%). hypothyroidism (3%), bone necrosis (1%). Conclusion. - Prophylactic cervical radiotherapy in laryngeal cancers resulted in 6% cervical node recurrence rate. This value may resent the maximal rate to accept if one would favour new therapeutic strategies based on restricted indications for radiotherapy. (authors)

  4. How to use PET/CT in the evaluation of response to radiotherapy.

    Science.gov (United States)

    Decazes, Pierre; Thureau, Sébastien; Dubray, Bernard; Vera, Pierre

    2017-11-28

    Radiotherapy is a major treatment modality for many cancers. Tumor response after radiotherapy determines the subsequent steps of the patient's management (surveillance, adjuvant or salvage treatment and palliative care). Tumor response assessed during radiotherapy offers a promising opportunity to adapt the treatment plan to reduced / increased target volume, to specifically target sub-volumes with relevant biological characteristics (metabolism, hypoxia, proliferation ...) and to further spare the organs at risk. In addition to its role in the diagnosis and the initial staging, Positron Emission Tomography combined with a Computed Tomography (PET/CT) provides functional information and is therefore attractive to evaluate tumor response. To review the published data addressing PET/CT as an evaluation tool in irradiated tumors. Reports on PET/CT acquired at various times (during radiotherapy, after initial (chemo-)radiotherapy, after definitive radiotherapy and during posttreatment follow-up) in solid tumors (lung, head-and-neck, cervix, esophagus, prostate and rectum) were collected and reviewed. Various tracers and technical are also discussed. 18F-FDG PET/CT has a well-established role in clinical routine after definitive chemo-radiotherapy for locally advanced head-and-neck cancers. 18F-choline PET/CT is indicated in prostate cancer patients with biochemical failure. 18F-FDG PET/CT is optional in many others circumstances and the clinical benefits of assessing tumor response with PET/CT remain a field of very active research. The combination of PET with Magnetic Resonance Imaging (PET/MRI) may prove to be valuable in irradiated rectal and cervix cancers. Tumor response can be evaluated by PET/CT with clinical consequences in multiple situations, notably in head and neck and prostate cancers, after radiotherapy. Further clinical evaluation for most cancers is still needed, possibly in association to MRI.

  5. A review of dental treatment of head and neck cancer patients, before, during and after radiotherapy: part 1.

    Science.gov (United States)

    Jawad, H; Hodson, N A; Nixon, P J

    2015-01-01

    The incidence of head and neck cancer is on the rise. Most head and neck cancers are treated with surgery, radiotherapy, chemotherapy or a combination of these modalities. Patients undergoing radiotherapy can experience several unwanted oral side effects, which have both short and long term implications. Dental general practitioners should be aware of these implications and should liaise closely with the restorative consultants and the oncology team to establish the best oral care pathway. This two-part series is a review of the oral changes that occur during and after radiotherapy and the oral management of head and neck oncology before, during and after radiotherapy. This article deals with both immediate sequelae such as cellulitis, mucositis, dysphagia, dysguesia and weight loss as well as long term sequelae such as rampant caries, trismus, xerostomia and osteoradionecrosis. It also encompasses the importance and need for pre-radiotherapy assessment.

  6. Radiotherapy and local control in rectal cancer.

    Science.gov (United States)

    Valentini, V; Rosetto, M E; Fares, C; Mantini, G; Salvi, G; Turriziani, A

    1998-01-01

    Recurrence is a stage in the natural history of rectal cancer. Preoperative radiotherapy or postoperative radiochemotherapy lower the rate of recurrence, improving local control. From 1980 to 1997, at the "Divisione di Radioterapia" of the "Università Cattolica del S. Cuore" of Rome 380 patients with rectal cancer of early clinical stage T2-3, candidates for surgery for cure, underwent radiation therapy. 119 patients underwent postoperative radiotherapy (45-50 Gy); 45 patients underwent "sandwich" radiotherapy (45 Gy:27 Gy before and 28 Gy after surgery), of whom 7 were treated with preoperative radiotherapy alone; 145 patients underwent preoperative concomitant radiochemotherapy according to 3 different protocols, radiotherapy (38 Gy) combined with mitomycin C and 5-FU; radiotherapy (50.4 Gy) combined with cisplatin and 5-FU; radiotherapy (45 Gy) combined with 5-FU and folinic acid. 71 patients were treated with preoperative radiotherapy (38 Gy) combined with IORT (10 Gy). Median follow-up was 6 years. Overall local control was 85% at 3 years, 83% at 5 years, 81% at 10 years. The rate of local control at 5 years was: 76% for postoperative radiotherapy, 83% for "sandwich" radiotherapy, 84% for preoperative radiochemotherapy and 93% for preoperative radiotherapy combined with IORT. Local control was shown to be significantly better with preoperative treatment as compared to postoperative treatment (p = 0.02). The incidence of metastases was 35% in the patients with local recurrence and 16% in those with local control. The difference in survival was highly significant in patients with local control as compared to those with local recurrence: at 5 years 87% and 32% respectively. Patients with local control showed a lower incidence of metastasis and a better survival.

  7. Treatment outcome in patients with vulvar cancer: comparison of concurrent radiotherapy to postoperative radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ja Young; Kim, Sung Hwan; Kim, Ki Won; Park, Dong Choon; Yoon, Joo Hee; Yoon, Sei Chul [St. Vincent' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of); Yu, Mina [St. Mary' s Hospital, The Catholic University of Korea School of Medicine, Seoul (Korea, Republic of)

    2012-03-15

    To evaluate outcome and morbidity in patients with vulvar cancer treated with radiotherapy, concurrent chemoradiotherapy or postoperative radiotherapy. The records of 24 patients treated with radiotherapy for vulvar cancer between July 1993 and September 2009 were retrospectively reviewed. All patients received once daily 1.8-4 Gy fractions external beam radiotherapy to median 51.2 Gy (range, 19.8 to 81.6 Gy) on pelvis and inguinal nodes. Seven patients were treated with primary concurrent chemoradiotherapy, one patient was treated with primary radiotherapy alone, four patients received palliative radiotherapy, and twelve patients were treated with postoperative radiotherapy. Twenty patients were eligible for response evaluation. Response rate was 55% (11/20). The 5-year disease free survival was 42.2% and 5-year overall survival was 46.2%, respectively. Fifty percent (12/24) experienced with acute skin complications of grade III or more during radiotherapy. Late complications were found in 8 patients. 50% (6/12) of patients treated with lymph node dissection experienced severe late complications. One patient died of sepsis from lymphedema. However, only 16.6% (2/12) of patients treated with primary radiotherapy developed late complications. Outcome of patients with vulvar cancer treated with radiotherapy showed relatively good local control and low recurrence. Severe late toxicities remained higher in patients treated with both node dissection and radiotherapy.

  8. Targeted Radiotherapy of Estrogen Receptor Positive Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan Rajagopalan

    2006-08-31

    The overall objectives of the proposal were to develop estrogen receptor (ER) binding small molecule radiopharmaceuticals for targeted radiotherapy of ER positive (ER+) tumors. In particular, this proposal focused on embedding a {sup 186,188}Re or a {sup 32}P radionuclide into an estrogen steroidal framework by isosteric substitution such that the resulting structure is topologically similar to the estrogen (estrogen mimic). The estrogen mimic molecules expected to bind to the ER and exhibit biodistribution akin to that of native estrogen due to structural mimicry. It is anticipated that the {sup 186,188}Re- or a {sup 32}P-containing estrogen mimics will be useful for targeted molecular radiotherapy of ER+ tumors. It is well established that the in vivo target tissue uptake of estrogen like steroidal molecules is related to the binding of the steroids to sex hormone binding globulin (SHBG). SHBG is important in the uptake of estrogens and testosterone in target tissues by SHBG receptors on the cell surface. However, hitherto the design of estrogen like small molecule radiopharmaceuticals was focused on optimizing ER binding characteristics without emphasis on SHBG binding properties. Consequently, even the molecules with good ER affinity in vitro, performed poorly in biodistribution studies. Based on molecular modeling studies the proposal focused on developing estrogen mimics 1-3 which were topologically similar to native estrogens, and form hydrogen bonds in ER and SHBG in the same manner as those of native estrogens. To this end the technical objectives of the proposal focused on synthesizing the rhenium-estrone and estradiol mimics 1 and 2 respectively, and phosphorous estradiol mimic 3 and to assess their stability and in vitro binding characteristics to ER and SHBG.

  9. 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...

  10. Italian survey in postoperative radiation therapy for prostate carcinoma by the AIRO National Working Group on Prostate Radiotherapy: definitive results.

    Science.gov (United States)

    Malinverni, Giuseppe; Greco, Carlo; Bianchi, Pieromaria; Busutti, Luciano; Cagna, Emanuela; Cozzarini, Cesare; Del Duca, Massimo; Franzone, Paola; Frezza, Giovanni; Gabriele, Pietro; Genovesi, Domenico; Girelli, Giuseppe Franco; Italia, Corrado; Mandoliti, Giovanni; Mauro, Floranna; Nava, Simonetta; Pratissoli, Silvia; Saracino, Maria Bianca; Squillace, Luigi; Signor, Marco; Tagliagambe, Angiolo; Vavassori, Vittorio; Villa, Sergio; Zini, Giampaolo; Valdagni, Riccardo

    2005-01-01

    The National Working Group on Prostate Radiotherapy of AIRO (Associazione Italiana Radioterapia Oncologica, Italian Association of Radiotherapeutic Oncology) was established in March 2001. A retrospective multi-center survey was performed to analyze the patterns of care for prostate cancer patients treated with postoperative radiotherapy following radical prostatectomy in Italy with regard to the year 2000. A structured questionnaire was mailed to 47 Italian radiotherapy centers to assess patient accrual in the postoperative setting in the interval comprised between period January-December 2000. Numbers of patients treated for different stages, specific prognostic factors indicating the need for adjuvant radiotherapy, fractionation schedules and prescription doses were acquired as well as other clinically important factors such as radiotherapy timing and the use of hormone therapy. More technical features of the treatment, such as patient positioning, mode of simulation, typical field setup and dose prescription criteria were also included in the questionnaire. The questionnaire was returned by 24 radiotherapy Institutions (51%) with a total number of 470 patients treated postoperatively in the year 2000. An average of about 20 patients were enrolled by each radiotherapy center. The age range was 45-81 years. Radiotherapy was delivered within 6 months of radical prostatectomy in 297 patients (65.4%) (mean, 3.4 months). In 157 (34.6%), the treatment was delivered as a salvage approach for biochemical or micro-macroscopic recurrence. Most of patients had locally advanced stage disease (pT3-pT4) (76%). Unfavorable prognostic factors, such as positive margins, capsular invasion, Gleason pattern score > 7 were present in about 50% of patients. The study confirmed that important risk factors for recurrences are present in a significant percentage of patients treated by radical prostatectomy. The number of patients that would benefit from adjuvant radiotherapy is

  11. PET/CT and radiotherapy : data transfer, radiotherapy workflow and quality assurance.

    Science.gov (United States)

    Fioroni, F; Iotti, C; Paiusco, M; Versari, A; Grassi, E; Salvo, D; Iori, M

    2010-10-01

    The development of new technologies in radiation therapy has made it possible to introduce more sophisticated techniques that can deliver the prescribed dose with more conformation and accuracy and to apply dose escalation protocols without increasing the risk of healthy tissue damage. This has consented the simultaneous delivery of different dose levels to different parts of the target, making it possible to boost those tumour sub-volumes that are considered more radio resistant. The use of PET for radiotherapy planning purposes has become increasingly important in the last few years, because of its ability to provide valuable biologic and functional data. PET imaging can affect the treatment strategy definition and improve the target delineation and the assessment of therapy response. The most attractive aspect is the perspective to deliver differential doses inside target volumes for areas of different biologic behaviour based on functional imaging, moving closer to the goals of biologically conformal radiation therapy. Each single step of PET/CT-guided radiotherapy workflow, needs to be performed following high standard procedures, within a rigorous and appropriate quality assurance protocol to minimize the sources of errors and to maximize the efficacy of PET imaging in radiation therapy, ensuring safe and effective use of the technology. The present paper focuses on aspects concerning the use of PET/CT in radiation treatment process, with the aim to delineate different possible approaches to its clinical application and to highlight the critical aspects of the various subprocesses.

  12. Post-mastectomy radiotherapy in Denmark

    DEFF Research Database (Denmark)

    Thomsen, Mette S; Berg, Martin; Nielsen, Hanne M

    2008-01-01

    This paper describes the procedure of changing from 2D to 3D treatment planning guidelines for post-mastectomy radiotherapy in Denmark. The aim of introducing 3D planning for post-mastectomy radiotherapy was to optimize the target coverage and minimize the dose to the normal tissues. Initially, i...

  13. Three dimensional conformal postoperative radiotherapy for ...

    African Journals Online (AJOL)

    Introduction: Postoperative radiotherapy of the parotid gland could be achieved with various radiotherapy techniques. However they irradiate differently the surrounding organs at risk (OARs) in particular the cochlea, oral cavity & contralateral parotid causing significant increase in the risk of oral mucositis, xerostomia, and ...

  14. Assessment of influence of OSL dosimeters in the skin dose in radiotherapy: study for Monte Carlo simulation; Avaliacao da influencia de dosimetros OSL na dose na pele em radioterapia: estudo por simulacao Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Schuch, Franciely F.; Nicolucci, Patricia, E-mail: franschuch@yahoo.com.br [Universidade de Sao Paulo (USP), Ribeiraoo Preto, SP (Brazil)

    2017-11-01

    The interest in optically stimulated luminescence (OSL) dosimetry materials is growing due to its potential use in quality control in Radiotherapy. The use of these dosimeters for in vivo dosimetry, however, may influence the dose to the skin and deeper tissues in the patient. The goal of this study is to evaluate the influence of the OSL Al{sub 2}O{sub 3} material in dose deposited in the skin and deep in Radiotherapy. Monte Carlo simulation is used to evaluate this purpose when OSL dosimeters of Al{sub 2}O{sub 3} are positioned on the skin surface of the patient. Percentage depth dose curves for clinical beams of 6 and 10 MV were simulated with and without the presence of the dosimeter on the surface of a water phantom. The results showed a decrease of doses in regions close to the surface of the skin. In the build-up region, the maximum decreases of dose produced by the presence of the dosimeters were 52,5% and 47,5% for the 6 and 10 MV beams, respectively. After the build-up region, there are not significant changes in the doses for any of the used beams. The differences of doses found are due to the influence of the dosimetric material on the relative fluence of electrons near the end surface of the dosimeter. Thus, the results showed that the presence of the dosimetric material on the surface interferes on the skin dose. However, these dosimeters do not cause dose variations in depths of clinical interest, allowing its application in routine in vivo dosimetry in Radiotherapy. (author)

  15. Radiotherapy for Oligometastatic Lung Cancer

    Directory of Open Access Journals (Sweden)

    Derek P. Bergsma

    2017-09-01

    Full Text Available Non-small cell lung cancer (NSCLC typically presents at an advanced stage, which is often felt to be incurable, and such patients are usually treated with a palliative approach. Accumulating retrospective and prospective clinical evidence, including a recently completed randomized trial, support the existence of an oligometastatic disease state wherein select individuals with advanced NSCLC may experience historically unprecedented prolonged survival with aggressive local treatments, consisting of radiotherapy and/or surgery, to limited sites of metastatic disease. This is reflected in the most recent AJCC staging subcategorizing metastatic disease into intra-thoracic (M1a, a single extra thoracic site (M1b, and more diffuse metastases (M1c. In the field of radiation oncology, recent technological advances have allowed for the delivery of very high, potentially ablative, doses of radiotherapy to both intra- and extra-cranial disease sites, referred to as stereotactic radiosurgery and stereotactic body radiotherapy (or SABR, in much shorter time periods compared to conventional radiation and with minimal associated toxicity. At the same time, significant improvements in systemic therapy, including platinum-based doublet chemotherapy, molecular agents targeting oncogene-addicted NSCLC, and immunotherapy in the form of checkpoint inhibitors, have led to improved control of micro-metastatic disease and extended survival sparking newfound interest in combining these agents with ablative local therapies to provide additive, and in the case of radiation and immunotherapy, potentially synergistic, effects in order to further improve progression-free and overall survival. Currently, despite the tantalizing potential associated with aggressive local therapy in the setting of oligometastatic NSCLC, well-designed prospective randomized controlled trials sufficiently powered to detect and measure the possible added benefit afforded by this approach are

  16. Postoperative radiotherapy for endometrial cancer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Eun Cheol; Kim, Jin Hee; Kim, Ok Bae; Byun, Sang Jun; Park, Seung Gyu; Kwon, Sang Hoon [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2012-09-15

    To investigate the prognostic factors and effectiveness of postoperative radiotherapy alone for endometrial carcinoma. Sixty four patients with stage I?III endometrial cancer (EC) treated with postoperative radiotherapy alone between January 1989 and December 2008 at the Keimyung University Dongsan Medical Center were chosen for the present study. Typically, total hysterectomy, salpingo-oophorectomy and lymphadenectomy were performed on the patient's pelvis. Total dose from 50.4 Gy to 63 Gy was irradiated at pelvis or extended fi eld. Thirteen patients were treated with Co-60 or Ir-192 intracavitary radiotherapy. Follow-up periods were from 7 to 270 months, with a median of 56 months. Five year overall survival (OS) rate was 58.7%, respectively. Five year disease-free survival (DFS) rate was 59.2%, respectively. In univariate analysis for OS and DFS, stage, menopausal age, type of operation, serosal invasion, and lymph node involvement were found to be statistically significant. Histologic type was marginally significant. In multivariate analysis for OS and DFS, stage, types of operation, histologic type were also found to be statistically significant. Treatment failure occurred in 14 patients. The main pattern of failure was found to be distant metastasis. Time to distant metastasis was from 3 to 86 months (median, 12 months). There were no grade 3 or 4 complications. Stage, types of operation, and histologic type could be the predictive prognostic factors in patients. We contemplated postoperative radiation as effective and safe treatment method for EC. Additional treatment would be needed to reduce distant metastasis.

  17. Intensity modulated radiotherapy of non-small-cell lung cancer incorporating SPECT ventilation imaging.

    Science.gov (United States)

    Munawar, Iram; Yaremko, Brian P; Craig, Jeff; Oliver, Michael; Gaede, Stewart; Rodrigues, George; Yu, Edward; Reid, Robert Henderson; Leung, Eugene; Urbain, Jean-Luc; Chen, Jeff; Wong, Eugene

    2010-04-01

    The authors performed this retrospective study to investigate the impact of using ventilation scans obtained from single photon emission computed tomography (SPECT) in selecting beam directions in intensity modulated radiation therapy (IMRT) planning in lung cancer radiotherapy to spare dosimetrically well ventilated lung. For ten consecutive stage III non-small-cell lung cancer patients, the authors obtained both ventilation/perfusion SPECT scans and four-dimensional CT scans for treatment planning purposes. Each ventilation scan was registered with the corresponding planning CT and ventilation volumes corresponding to either > or = 50% (vv50) or > or = 70% (vv70) of the maximum SPECT count were automatically segmented. For each patient, three IMRT plans were generated: One using nine equally spaced beams optimized according to nonfunctional lung based mean lung dose and lung v20; a second using nine equally spaced beams optimized to avoid vv50 and vv70; and a third plan using only three beams with gantry angles chosen based on minimum mean ventilated lung dose calculated for each conformal beam at every 10 degrees gantry angle avoiding vv50 and vv70. Resultant dose volume histogram indices were calculated for each plan and were compared with respect to calculated SPECT-based ventilation parameters in order to quantify the potential utility of ventilation SPECT in this setting. Two patient groups were identified based on (i) the overlap volume between PTV and vv50 and (ii) the average angular mean ventilated lung dose (AAMvLD). The first parameter quantifies the proximity of the PTV to well ventilated lung and the second parameter quantifies the degree of ventilation that surrounds the PTV. For group 1 patients, 5% of the vv50 overlapped the PTV. Group 1 was further classified into subgroups 1A and 1B: For subgroup 1A, AAMvLD is >18 Gy, implying that the functional lung surrounds the PTV; for subgroup 1B, AAMvLD is ventilated lung does not completely surround PTV

  18. Basic radiotherapy physics and biology

    CERN Document Server

    Chang, David S; Das, Indra J; Mendonca, Marc S; Dynlacht, Joseph R

    2014-01-01

    This book is a concise and well-illustrated review of the physics and biology of radiation therapy intended for radiation oncology residents, radiation therapists, dosimetrists, and physicists. It presents topics that are included on the Radiation Therapy Physics and Biology examinations and is designed with the intent of presenting information in an easily digestible format with maximum retention in mind. The inclusion of mnemonics, rules of thumb, and reader-friendly illustrations throughout the book help to make difficult concepts easier to grasp. Basic Radiotherapy Physics and Biology is a

  19. Quality and safety in radiotherapy

    CERN Document Server

    Pawlicki, Todd

    2010-01-01

    The first text to focus solely on quality and safety in radiotherapy, this work encompasses not only traditional, more technically oriented, quality assurance activities, but also general approaches of quality and safety. It includes contributions from experts both inside and outside the field to present a global view. The task of assuring quality is no longer viewed solely as a technical, equipment-dependent endeavor. Instead, it is now recognized as depending on both the processes and the people delivering the service. Divided into seven broad categories, the text covers: Quality Management

  20. Radiotherapy in patients with connective tissue diseases.

    Science.gov (United States)

    Giaj-Levra, Niccolò; Sciascia, Savino; Fiorentino, Alba; Fersino, Sergio; Mazzola, Rosario; Ricchetti, Francesco; Roccatello, Dario; Alongi, Filippo

    2016-03-01

    The decision to offer radiotherapy in patients with connective tissue diseases continues to be challenging. Radiotherapy might trigger the onset of connective tissue diseases by increasing the expression of self-antigens, diminishing regulatory T-cell activity, and activating effectors of innate immunity (dendritic cells) through Toll-like receptor-dependent mechanisms, all of which could potentially lead to breaks of immune tolerance. This potential risk has raised some debate among radiation oncologists about whether patients with connective tissue diseases can tolerate radiation as well as people without connective tissue diseases. Because the number of patients with cancer and connective tissue diseases needing radiotherapy will probably increase due to improvements in medical treatment and longer life expectancy, the issue of interactions between radiotherapy and connective tissue diseases needs to be clearer. In this Review, we discuss available data and evidence for patients with connective tissue diseases treated with radiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Geometrical and dosimetrical uncertainties in hypofractionated radiotherapy of the lung: A review.

    Science.gov (United States)

    Schwarz, Marco; Cattaneo, Giovanni Mauro; Marrazzo, Livia

    2017-04-01

    The application of high precision hypofractionated regimes (a.k.a. stereotactic body radiotherapy (SBRT)) to the treatment of lung cancer is a 'success story' of radiotherapy. From the technical perspective, lung SBRT is a challenging technique as all aspects of the treatment workflow, from imaging to dose calculation to treatment delivery, should be carefully handled in order to ensure consistency between planned and delivered dose. In this review such technical aspects are presented and discussed, looking at what has been developed over the years. The use of imaging techniques such as slow-CT, breath-hold CT, four-dimensional CT and mid-ventilation is reviewed, presenting the main characteristics of each approach but not necessarily to single out 'the best' solution. Concerning dose calculation, a number of studies clearly separate dose algorithms that should be considered inadequate for lung SBRT (e.g. simple pencil beam algorithms) from approaches such as convolution algorithms, Monte Carlo, and solution of the transport equation, that are much better at handling the combination of small fields and heterogenenous geometries that make dose calculation not trivial. Patient positioning and management of intrafraction motion have been two areas of significant developments, to the point where it is difficult to identify which solution represents the best compromise between technical complexity and clinical effectiveness. The review analyses several of these methods, outlining the residual uncertainties associated with each of them. Last but not least, two subjects are discussed, adaptive therapy and particle therapy, that may represent in the near future additional tools for the technical improvement of lung SBRT. Copyright © 2017. Published by Elsevier Ltd.

  2. Investment in radiotherapy infrastructure positively affected the economic status of an oncology hospital

    Science.gov (United States)

    Śmigielska, Mirella; Milecki, Piotr

    2012-01-01

    Background Radiotherapy is among the most efficient treatment methods of cancer. However, a radiotherapy base needs a substantial financial investment, especially before the beginning of its operation, and in some cases, in developing countries such a huge investment may cause some financial disturbances for a hospital concerned. Aim To assess the influence of investments modernizing the radiotherapy base in the period between 2000 and 2007 on the financial condition of the oncology hospital in the region with population of about 3 million. Material and methods Financial reports and medical statistics for the period between 2000 and 2007 from the studied oncology hospital and a recognized staffing model, as well as data on epidemiological situation of the region have been used to calculate the economic effects of financial investment in the radiotherapy base. Results The growth of RT therapeutic potential has been driven by two cost-effective investment programmes. The total amount invested in both programmes was PLN 127,191,000. The number of radiotherapy patients treated in the hospital increased from 2301 in 2000 to 4799 in 2007 with a the same number of five therapeutic machines, although all five of them were replaced over that period. Investments modernizing the radiotherapy base lead to a significant increase in depreciation and operating costs, which adversely affects financial results of the hospital. Conclusion Long term trends showed that investments had positive influence on hospital performance shown both in increased income and larger number of patients treated. PMID:24377017

  3. Efficacy of Rasayana Avaleha as adjuvant to radiotherapy and chemotherapy in reducing adverse effects.

    Science.gov (United States)

    Vyas, Purvi; Thakar, A B; Baghel, M S; Sisodia, Arvind; Deole, Yogesh

    2010-10-01

    Cancer is the most dreadful disease affecting mankind. The available treatments such as chemotherapy and radiotherapy have cytotoxic effects, which are hazardous to the normal cells of the patient, causing many unnecessary effects. This further leads to complications of the therapy, impaired health, and deterioration of quality of life, resulting in mandatory stoppage of the treatment. In the present study, the efficacy of an Ayurvedic formulation, Rasayana Avaleha, has been evaluated as an adjuvant medication to modern radiotherapy and chemotherapy. A total of 36 cancer patients were registered in this trial and were divided into two groups, group A and group B. In group A, the patients were treated with radiotherapy and chemotherapy along with adjuvant Rasayana Avaleha (RT + CT + RA), while in group B only radiotherapy and chemotherapy (RT + CT) were given, as the control group. After assessing the results, it was observed that Rasayana Avaleha gave better results in controlling the adverse effect of chemotherapy and radiotherapy in comparison with the control group. Therefore, Rasayana Avaleha has proved to be an effective adjuvant therapy in protecting patients from the adverse effects of chemotherapy and radiotherapy.

  4. Optimization of human cancer radiotherapy

    CERN Document Server

    Swan, George W

    1981-01-01

    The mathematical models in this book are concerned with a variety of approaches to the manner in which the clinical radiologic treatment of human neoplasms can be improved. These improvements comprise ways of delivering radiation to the malignan­ cies so as to create considerable damage to tumor cells while sparing neighboring normal tissues. There is no unique way of dealing with these improvements. Accord­ ingly, in this book a number of different presentations are given. Each presentation has as its goal some aspect of the improvement, or optimization, of radiotherapy. This book is a collection of current ideas concerned with the optimization of human cancer radiotherapy. It is hoped that readers will build on this collection and develop superior approaches for the understanding of the ways to improve therapy. The author owes a special debt of thanks to Kathy Prindle who breezed through the typing of this book with considerable dexterity. TABLE OF CONTENTS Chapter GENERAL INTRODUCTION 1. 1 Introduction 1...

  5. Craniospinal radiotherapy in adult medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Selek, U.; Zorlu, F.; Hurmuz, P.; Cengiz, M.; Gurkaynak, M. [Hacettepe Univ., Ankara (Turkey). Dept. of Radiation Oncology; Turker, A. [Hacettepe Univ., Ankara (Turkey). Dept. of Internal Medicine; Soylemezoglu, F. [Hacettepe Univ., Ankara (Turkey). Dept. of Pathology

    2007-05-15

    Purpose: To evaluate the outcome and prognostic factors of adult patients with medulloblastoma. Patients and Methods: 26 adult medulloblastoma patients with a median age of 27 were subjected to craniospinal radiotherapy. A dose of 30.6 Gy with 1.8 Gy/fraction/day was prescribed to M0 patients, while 36 Gy were to be applied in patients with positive cerebrospinal liquor findings. The posterior fossa was boosted to 54 Gy. While 20 patients underwent external-beam radiotherapy alone, only six received sequential adjuvant chemotherapy. Results: Male/female ratio was 1.2. Preradiotherapy Karnofsky performance status was recorded as median 100%. 50% were classified as poor risk (n = 10, subtotal resection; n = 3, M+). The median follow-up time was 46.5 months. The 5-year actuarial survival rates for recurrence-free, distant metastasis-free, disease-free, and overall survival were 82.5%, 90.8%, 73.5%, and 89.7%, respectively. Patient characteristics, treatment factors and tumor characteristics failed to show any significance in univariate analysis. Grade 3 or 4 late morbidities were not observed. Conclusion: Yet, the current standard of care seems to remain craniospinal irradiation after maximal surgical resection of the primary neoplasm without clear indications for adjuvant chemotherapy. (orig.)

  6. [Percutaneous radiotherapy of bone metastases].

    Science.gov (United States)

    Schüller, H; Wisser, L; Pauleit, D

    1997-09-01

    Bone metastases causing pain syndromes and imminent pathologic fractures are among the main reasons for radiotherapy in patients suffering from malignant tumors. The indication is much influenced by the radiologic findings. Surgical methods are to be chosen in the first place in cases of pathologic fractures or patients with a high risk of such fractures. Different authors recommend various therapeutic regimens. Effective pain control can be achieved with one single dose of radiation. Doses of 6 to 40 Gy applied in one to 19 days are also efficient. Side effects, especially nausea and vomiting occur in 25% of cases; this number rises to 50% in cases of half body irradiation. Visible changes of bone mineral density may be noticed about 6 weeks after termination of radiotherapy. About 70% of osteolytic metastases show progressive sclerosis whereas osteosclerotic lesions may show both increase or decline of bone mass. In spite many years of experience the optimal strategy for radiation therapy of bone metastasis has not been defined; further studies are needed.

  7. Standard-Fractionated Radiotherapy for Optic Nerve Sheath Meningioma: Visual Outcome Is Predicted by Mean Eye Dose

    Energy Technology Data Exchange (ETDEWEB)

    Abouaf, Lucie [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Girard, Nicolas [Radiotherapy-Oncology Department, Lyon Sud Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Lefort, Thibaud [Neuro-Radiology Department, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); D' hombres, Anne [Claude Bernard University, Lyon (France); Tilikete, Caroline; Vighetto, Alain [Neuro-Ophthalmology Unit, Pierre-Wertheimer Hospital, Hospices Civils de Lyon, Lyon (France); Claude Bernard University, Lyon (France); Mornex, Francoise, E-mail: francoise.mornex@chu-lyon.fr [Claude Bernard University, Lyon (France)

    2012-03-01

    Purpose: Radiotherapy has shown its efficacy in controlling optic nerve sheath meningiomas (ONSM) tumor growth while allowing visual acuity to improve or stabilize. However, radiation-induced toxicity may ultimately jeopardize the functional benefit. The purpose of this study was to identify predictive factors of poor visual outcome in patients receiving radiotherapy for ONSM. Methods and Materials: We conducted an extensive analysis of 10 patients with ONSM with regard to clinical, radiologic, and dosimetric aspects. All patients were treated with conformal radiotherapy and subsequently underwent biannual neuroophthalmologic and imaging assessments. Pretreatment and posttreatment values of visual acuity and visual field were compared with Wilcoxon's signed rank test. Results: Visual acuity values significantly improved after radiotherapy. After a median follow-up time of 51 months, 6 patients had improved visual acuity, 4 patients had improved visual field, 1 patient was in stable condition, and 1 patient had deteriorated visual acuity and visual field. Tumor control rate was 100% at magnetic resonance imaging assessment. Visual acuity deterioration after radiotherapy was related to radiation-induced retinopathy in 2 patients and radiation-induced mature cataract in 1 patient. Study of radiotherapy parameters showed that the mean eye dose was significantly higher in those 3 patients who had deteriorated vision. Conclusions: Our study confirms that radiotherapy is efficient in treating ONSM. Long-term visual outcome may be compromised by radiation-induced side effects. Mean eye dose has to be considered as a limiting constraint in treatment planning.

  8. Psychological and physical distress of cancer patients during radiotherapy

    CERN Document Server

    König, A

    2001-01-01

    Purpose: patients undergoing radiotherapy have physical and psychological symptoms related to the underlying disease and the treatment. In order to give the best possible support to the patients, more knowledge about the amount and the changing of distress in the course of radiotherapy is of essentially importance. Methods: The distress was measured in a consecutive sample of cancer patients (n=82) undergoing radiotherapy. Each patient was given the EORTC-QLQ-C30, the HADS and a special questionnaire which ascertain radiotherapy-specific items before starting the radiotherapy, at the onset of radiotherapy, in the third week of radiotherapy and 3 weeks after the end of radiotherapy. Results: within the first week of treatment the psychological distress of the patients is increasing; 98.8 % of the patients are 'moderate distressed', 46 % 'severe distressed'. General physical symptoms seem not to be affected by the radiotherapy, there is no changing. The distress caused by the organization of the radiotherapy is...

  9. Concurrent chemotherapy and radiotherapy for cervical cancer.

    Science.gov (United States)

    Martín-Martínez, A; Molano, F; Lloret, M; Falcón-Vizcaino, O; García-Hernández, J A

    2003-01-01

    To compare the results obtained following treatment, from a group of patients with locally advanced cervical cancer (Stage IB or higher) treated with concurrent chemotherapy and radiotherapy in relation to a group of patients treated exclusively with radiotherapy. All patients treated with concurrent chemotherapy and radiotherapy at the Gynaecologic Oncology Unit of the University Hospital Materno Infantil of the Canaries between 1999 and 2000, both inclusive, were included. The first group to be considered was formed by patients who received combined treatment. The second group of patients received radiotherapy exclusively, having been treated in previous years (1997-1998 period). The results were compared in relation to survival in the two following years from treatment (2000-2001) in the group of combined treatment and years 1999-2000 in the group that received only radiotherapy. To compare the survival of both groups the chi-square test and Odds Ratio were utilised. The groups compared are homogeneous when looking at the stage of the disease when diagnosed, the histological type of tumour and its degree of cellular differentiation, the CAT results and tumoral markers. Survival of more than two years was observed in the group treated with concurrent chemotherapy and radiotherapy in relation to the group treated exclusively with radiotherapy; chi-square 9.92, p < 0.01, OR: 0.1 (0.01-0.6).

  10. Predictors for trismus in patients receiving radiotherapy.

    Science.gov (United States)

    van der Geer, S Joyce; Kamstra, Jolanda I; Roodenburg, Jan L N; van Leeuwen, Marianne; Reintsema, Harry; Langendijk, Johannes A; Dijkstra, Pieter U

    2016-11-01

    Trismus, a restricted mouth opening in head and neck cancer patients may be caused by tumor infiltration in masticatory muscles, radiation-induced fibrosis or scarring after surgery. It may impede oral functioning severely. The aims of our study were to determine: (1) the incidence of trismus at various time points; and (2) the patient, tumor, and treatment characteristics that predict the development of trismus after radiotherapy in head and neck cancer patients using a large database (n = 641). Maximal mouth opening was measured prior to and 6, 12, 18, 24, 36, and 48 months after radiotherapy. Patient, tumor, and treatment characteristics were analyzed as potential predictors for trismus using a multivariable logistic regression analysis. At six months after radiotherapy, 28.1% of the patients without trismus prior to radiotherapy developed trismus for the first time. At subsequent time points the incidence declined. Over a total period of 48 months after radiotherapy, the incidence of trismus was 3.6 per 10 person years at risk. Patients who had tumors located in the oral cavity, oropharynx or nasopharynx, and the salivary glands or ear, and who had a longer overall treatment time of radiotherapy, were more likely to develop trismus in the first six months after radiotherapy. Maximal mouth opening was a predictor for developing trismus at all time points. Incidence of trismus is 3.6 per 10 person years at risk. Tumor localization and overall treatment time of radiotherapy are predictors for developing trismus the first six months after radiotherapy. Maximal mouth opening is a significant predictor for developing trismus at all time points. Regular measurements of maximal mouth opening are needed to predict trismus.

  11. MRI of occult sacral insufficiency fractures following radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mammone, J.F. [Dept. of Radiology, Thomas Jefferson Univ. Hospital, and Jefferson Medical Coll., Philadelphia, PA (United States); Schweitzer, M.E. [Dept. of Radiology, Thomas Jefferson Univ. Hospital, and Jefferson Medical Coll., Philadelphia, PA (United States)

    1995-02-01

    Following radiation therapy, marrow abnormalities noted on magnetic resonance imaging (MRI) are frequent and may mimic metastases. Specific radiotherapy changes are usually easily identifiable; however, traumatic lesions cause more interpretive difficulties. We assessed the incidence and MRI characteristics of insufficiency fractures in this population. During a 5-year span (1987-1991), 546 patients received pelvic radiotherapy for primary malignancies. MRI was performed in 25 of these patients at least 3 months after treatment. The mean dose in this group was 53 Gy. These MRI scans were retrospectively reviewed for the appearance of the sacrum with particular attention to the presence of insufficiency fractures. This was correlated with clinical course and scintigraphic findings. Presumed insufficiency fractures on MRI paralleled the sacral side of the sacroiliac joint, enhanced with Gd-DTPA, were most prominent or initially seen anteriorly, and had ill-defined margins on all imaging sequences. The incidence of occult sacral insufficiency fractures was at least 20%. Insufficiency fractures of the sacrum in the post-radiotherapy patient are a relatively frequent occurrence which can mimic metastases. Consideration of this phenomenon and knowledge of differential features may avoid overdiagnosis of osseous metastases. (orig.)

  12. Carotid artery stenosis after neck radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Shimamura, Munehisa; Hashimoto, Yoichiro; Kasuya, Junji; Terasaki, Tadashi [Kumamoto City Hospital (Japan); Uchino, Makoto

    2000-02-01

    Carotid artery stenosis sometimes occurs after cervical radiotherapy. We report a 70-year-old woman with a history of radiotherapy for thyroid cancer at the age of 28 years. She had no signs and symptoms except the skin lesion at the irradiation site. Duplex ultrasonography revealed heterogeneous plaques showing 50% stenosis of bilateral common carotid arteries. Those lesions were observed within segment of irradiation, where atheromatous plaque usually seldom occurs. These indicated that the carotid stenosis was induced by radiotherapy. Although the efficacy of antiplatelet therapy for radiation-induced plaque is not clear, the plaques remained unchanged for 4 years in spite of aspirin administration. (author)

  13. Monte Carlo Treatment Planning for Advanced Radiotherapy

    DEFF Research Database (Denmark)

    Cronholm, Rickard

    This Ph.d. project describes the development of a workflow for Monte Carlo Treatment Planning for clinical radiotherapy plans. The workflow may be utilized to perform an independent dose verification of treatment plans. Modern radiotherapy treatment delivery is often conducted by dynamically...... modulating the intensity of the field during the irradiation. The workflow described has the potential to fully model the dynamic delivery, including gantry rotation during irradiation, of modern radiotherapy. Three corner stones of Monte Carlo Treatment Planning are identified: Building, commissioning...

  14. Radiotherapy versus combined modality in early stages

    DEFF Research Database (Denmark)

    Specht, L; Carde, P; Mauch, P

    1992-01-01

    In early stage Hodgkin's disease the optimal choice of treatment for the individual patient is still an unresolved issue. So far, twenty-two randomized trials of radiotherapy alone versus radiotherapy plus combination chemotherapy have been carried out worldwide. The preliminary results of a global...... be reduced, and that the stress of experiencing a relapse is avoided in many patients. The major argument against the use of chemotherapy up front is: that by careful staging and selection of patients and by careful radiotherapy techniques the number of patients exposed to potentially toxic chemotherapy may...

  15. Second Malignant Neoplasms and Cardiovascular Disease Following Radiotherapy

    Science.gov (United States)

    Ng, Andrea K.; Allan, James M.; Pui, Ching-Hon; Kennedy, Ann R.; Xu, X. George; Purdy, James A.; Applegate, Kimberly; Yahalom, Joachim; Constine, Louis S.; Gilbert, Ethel S.; Boice, John D.

    2012-01-01

    Second malignant neoplasms (SMNs) and cardiovascular disease (CVD) are among the most serious and life-threatening late adverse effects experienced by the growing number of cancer survivors worldwide and are due in part to radiotherapy. The National Council on Radiation Protection and Measurements (NCRP) convened an expert scientific committee to critically and comprehensively review associations between radiotherapy and SMNs and CVD, taking into account radiobiology; genomics; treatment (ie, radiotherapy with or without chemotherapy and other therapies); type of radiation; and quantitative considerations (ie, dose–response relationships). Major conclusions of the NCRP include: 1) the relevance of older technologies for current risk assessment when organ-specific absorbed dose and the appropriate relative biological effectiveness are taken into account and 2) the identification of critical research needs with regard to newer radiation modalities, dose–response relationships, and genetic susceptibility. Recommendation for research priorities and infrastructural requirements include 1) long-term large-scale follow-up of extant cancer survivors and prospectively treated patients to characterize risks of SMNs and CVD in terms of radiation dose and type; 2) biological sample collection to integrate epidemiological studies with molecular and genetic evaluations; 3) investigation of interactions between radiotherapy and other potential confounding factors, such as age, sex, race, tobacco and alcohol use, dietary intake, energy balance, and other cofactors, as well as genetic susceptibility; 4) focusing on adolescent and young adult cancer survivors, given the sparse research in this population; and 5) construction of comprehensive risk prediction models for SMNs and CVD to permit the development of follow-up guidelines and prevention and intervention strategies. PMID:22312134

  16. Art therapy using famous painting appreciation maintains fatigue levels during radiotherapy in cancer patients

    Science.gov (United States)

    Koom, Woong Sub; Choi, Mi Yeon; Lee, Jeongshim; Park, Eun Jung; Kim, Ju Hye; Kim, Sun-Hyun; Kim, Yong Bae

    2016-01-01

    Purpose: The purpose of this study was to evaluate the efficacy of art therapy to control fatigue in cancer patients during course of radiotherapy and its impact on quality of life (QoL). Materials and Methods: Fifty cancer patients receiving radiotherapy received weekly art therapy sessions using famous painting appreciation. Fatigue and QoL were assessed using the Brief Fatigue Inventory (BFI) Scale and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) at baseline before starting radiotherapy, every week for 4 weeks during radiotherapy, and at the end of radiotherapy. Mean changes of scores over time were analyzed using a generalized linear mixed model. Results: Of the 50 patients, 34 (68%) participated in 4 sessions of art therapy. Generalized linear mixed models testing for the effect of time on mean score changes showed no significant changes in scores from baseline for the BFI and FACIT-F. The mean BFI score and FACIT-F total score changed from 3.1 to 2.7 and from 110.7 to 109.2, respectively. Art therapy based on the appreciation of famous paintings led to increases in self-esteem by increasing self-realization and forming social relationships. Conclusion: Fatigue and QoL in cancer patients with art therapy do not deteriorate during a period of radiotherapy. Despite the single-arm small number of participants and pilot design, this study provides a strong initial demonstration that art therapy of appreciation for famous painting is worthy of further study for fatigue and QoL improvement. Further, it can play an important role in routine practice in cancer patients during radiotherapy. PMID:27306778

  17. Acute and subacute cardiac complications following radiotherapy in patients with left breast cancer

    Directory of Open Access Journals (Sweden)

    Salari

    2008-08-01

    Full Text Available "nBackground: Radiation to some parts of the heart is unavoidable in the therapeutic course of primary tumors in many kinds of cancer, including breast cancer. The aim of this study was to assess the frequency of acute and subacute cardiac complications following radiotherapy in patients with left breast cancer. "nMethods: In this study, we enrolled 53 patients with left breast cancer who underwent mastectomy or lumpectomy between September 2005 and September 2006 in Imam Khomeini Hospital Complex, and subsequently underwent chemotherapy with anthracyclines (<450mg/m2 and Endoxan plus taxane/fFluorouracil followed by radiotherapy. In all patients, electrocardiography and echocardiography were performed before initiation of radiotherapy, immediately after radiotherapy and again three and six months later to check for radiotherapy-induced cardiac complications such as pericardial effusion, valvular lesions, left ventricular dysfunction, conduction system disturbances and other variables. "nResults: Thirty-nine patients completed the follow-up period. Among these, 10 (25.6% patients experienced cardiac complications following radiotherapy. Among these, mild pericardial effusion in seven (53.85% patients, mild mitral regurgitation in three cases (23.08% and Right Bundle Branch Block (RBBB in two cases (15.38% were the most common complications. We found no correlation between cardiac complication and tumor dose, dose fraction and type of chemotherapy protocol. We noted no cases of new or more serious complications, such as cardiomyopathies or coronary artery disease, nor any changes in ejection fraction by the end of the follow-up period. "nConclusion: In patients with left breast cancer, acute and subacute cardiac complications following radiotherapy are not serious and have no clinical significance. Further studies are needed for more assessments in this area.

  18. Art therapy using famous painting appreciation maintains fatigue levels during radiotherapy in cancer patients.

    Science.gov (United States)

    Koom, Woong Sub; Choi, Mi Yeon; Lee, Jeongshim; Park, Eun Jung; Kim, Ju Hye; Kim, Sun-Hyun; Kim, Yong Bae

    2016-06-01

    The purpose of this study was to evaluate the efficacy of art therapy to control fatigue in cancer patients during course of radiotherapy and its impact on quality of life (QoL). Fifty cancer patients receiving radiotherapy received weekly art therapy sessions using famous painting appreciation. Fatigue and QoL were assessed using the Brief Fatigue Inventory (BFI) Scale and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) at baseline before starting radiotherapy, every week for 4 weeks during radiotherapy, and at the end of radiotherapy. Mean changes of scores over time were analyzed using a generalized linear mixed model. Of the 50 patients, 34 (68%) participated in 4 sessions of art therapy. Generalized linear mixed models testing for the effect of time on mean score changes showed no significant changes in scores from baseline for the BFI and FACIT-F. The mean BFI score and FACIT-F total score changed from 3.1 to 2.7 and from 110.7 to 109.2, respectively. Art therapy based on the appreciation of famous paintings led to increases in self-esteem by increasing self-realization and forming social relationships. Fatigue and QoL in cancer patients with art therapy do not deteriorate during a period of radiotherapy. Despite the single-arm small number of participants and pilot design, this study provides a strong initial demonstration that art therapy of appreciation for famous painting is worthy of further study for fatigue and QoL improvement. Further, it can play an important role in routine practice in cancer patients during radiotherapy.

  19. Art therapy using famous painting appreciation maintains fatigue levels during radiotherapy in cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Koom, Woong Sub; Lee, Jeong Shin; Kim, Yong Bae [Dept. of Radiation Oncology, Yonsei University College of Medicine, Seoul (Korea, Republic of); Choi, Mi Yeon; Park, Eun Jung; Kim, Ju Hye; Kim, Sun Hyun [Graduate School of Clinical Art Therapy, CHA University, Pocheon (Korea, Republic of)

    2016-06-15

    The purpose of this study was to evaluate the efficacy of art therapy to control fatigue in cancer patients during course of radiotherapy and its impact on quality of life (QoL). Fifty cancer patients receiving radiotherapy received weekly art therapy sessions using famous painting appreciation. Fatigue and QoL were assessed using the Brief Fatigue Inventory (BFI) Scale and the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) at baseline before starting radiotherapy, every week for 4 weeks during radiotherapy, and at the end of radiotherapy. Mean changes of scores over time were analyzed using a generalized linear mixed model. Of the 50 patients, 34 (68%) participated in 4 sessions of art therapy. Generalized linear mixed models testing for the effect of time on mean score changes showed no significant changes in scores from baseline for the BFI and FACIT-F. The mean BFI score and FACIT-F total score changed from 3.1 to 2.7 and from 110.7 to 109.2, respectively. Art therapy based on the appreciation of famous paintings led to increases in self-esteem by increasing self-realization and forming social relationships. Fatigue and QoL in cancer patients with art therapy do not deteriorate during a period of radiotherapy. Despite the single-arm small number of participants and pilot design, this study provides a strong initial demonstration that art therapy of appreciation for famous painting is worthy of further study for fatigue and QoL improvement. Further, it can play an important role in routine practice in cancer patients during radiotherapy.

  20. Simulation of dosimetric consequences of 4D-CT-based motion margin estimation for proton radiotherapy using patient tumor motion data

    Science.gov (United States)

    Koybasi, Ozhan; Mishra, Pankaj; St. James, Sara; Lewis, John H.; Seco, Joao

    2014-02-01

    For the radiation treatment of lung cancer patients, four-dimensional computed tomography (4D-CT) is a common practice used clinically to image tumor motion and subsequently determine the internal target volume (ITV) from the maximum intensity projection (MIP) images. ITV, which is derived from short pre-treatment 4D-CT scan (variability. Inaccurate tumor localization may result in under-dosage of the tumor or over-dosage of the surrounding tissues. The purpose of this study is therefore to assess the degree of tumor under-dosage in case of regular and irregular breathing for proton radiotherapy using ITV-based treatment planning. We place a spherical lesion into a modified XCAT phantom that is also capable of producing 4D images based on irregular breathing, and move the tumor according to real tumor motion data, which is acquired over multiple days by tracking gold fiducial markers implanted into the lung tumors of patients. We derive ITVs by taking the union of all tumor positions during 6 s of tumor motion in the phantom using the first day patient tumor tracking data. This is equivalent to ITVs generated clinically from cine-mode 4D-CT MIP images. The treatment plans created for different ITVs are then implemented on dynamic phantoms with tumor motion governed by real tumor tracking data from consecutive days. By comparing gross tumor volume dose distribution on days of ‘treatment’ with the ITV dose distribution, we evaluate the deviation of the actually delivered dose from the predicted dose. Our results have shown that the proton treatment planning on ITV derived from pre-treatment cine-mode 4D-CT can result in under-dosage (dose covering 95% of volume) of the tumor by up to 25.7% over 3 min of treatment for the patient with irregular respiratory motion. Tumor under-dosage is less significant for the patient with relatively regular breathing. We have demonstrated that proton therapy using the pre-treatment 4D-CT based ITV method can lead to significant

  1. Introduction to Radiotherapy with Photon and Electron Beams and Treatment Planning from Conformal Radiotherapy to IMRT

    Science.gov (United States)

    Wilkens, Jan J.

    2007-11-01

    Besides surgery and chemotherapy, radiation therapy is one of the three main treatment options for cancer patients. This paper provides an introduction to the basic principles of radiotherapy with photons and electrons. It includes a brief summary of the physical properties for photon and electron beams as well as a description of treatment machines used to create these beams. The second part introduces the treatment planning process as it is commonly employed in radiotherapy. It covers dose calculation algorithms, conventional planning strategies for three-dimensional conformal radiotherapy, and optimization techniques for intensity modulated radiotherapy (IMRT).

  2. Adjuvant radiotherapy for stage I endometrial cancer

    Science.gov (United States)

    Kong, Anthony; Johnson, Nick; Kitchener, Henry C; Lawrie, Theresa A

    2014-01-01

    Background This is an updated version of the original Cochrane review published in Issue 2, 2007. The role of radiotherapy (both pelvic external beam radiotherapy (EBRT) and vaginal intracavity brachytherapy (VBT)) in stage I endometrial cancer following hysterectomy remains controversial. Objectives To assess the efficacy of adjuvant radiotherapy following surgery for stage I endometrial cancer. Search methods We searched The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and the Specialised Register to end-2005 for the original review, and extended the search to January 2012 for the update. Selection criteria We included randomised controlled trials (RCTs) that compared post-operative adjuvant radiotherapy (either EBRTor VBT, or both) versus no radiotherapy or VBT in women with stage I endometrial cancer. Data collection and analysis Two review authors independently assessed trials and extracted data to a specifically designed data collection form. The primary outcome was overall survival. Secondary outcomes were endometrial cancer-related deaths, locoregional recurrence and distant recurrence. Meta-analyses were performed using Cochrane Review Manager Software 5.1. Main results We included eight trials. Seven trials (3628 women) compared EBRT with no EBRT (or VBT), and one trial (645 women) compared VBTwith no additional treatment. We considered six of the eight trials to be of a high quality. Time-to-event data were not available for all trials and all outcomes. EBRT (with or without VBT) compared with no EBRT (or VBT alone) for stage I endometrial carcinoma significantly reduced locoregional recurrence (time-to-event data: five trials, 2965 women; Hazard Ratio (HR) 0.36, 95% Confidence Interval (CI) 0.25 to 0.52; and dichotomous data: seven trials, 3628 women; Risk Ratio (RR) 0.33, 95% CI 0.23 to 0.47). This reduced risk of locoregional recurrence did not translate into improved overall survival (time-to-event data: five trials, 2

  3. Correlating metabolic and anatomic responses of primary lung cancers to radiotherapy by combined F-18 FDG PET-CT imaging

    Directory of Open Access Journals (Sweden)

    Grills Inga

    2007-05-01

    Full Text Available Abstract Background To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy. Methods 36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters was correlated with that of maximum standard uptake value (SUV of the primary lung cancer before and after conventional radiotherapy. Results There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p Conclusion Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone.

  4. Immunotherapy Combined with Large Fractions of Radiotherapy: Stereotactic Radiosurgery for Brain Metastases—Implications for Intraoperative Radiotherapy after Resection

    Directory of Open Access Journals (Sweden)

    Carsten Herskind

    2017-07-01

    Full Text Available Brain metastases (BM affect approximately a third of all cancer patients with systemic disease. Treatment options include surgery, whole-brain radiotherapy, or stereotactic radiosurgery (SRS while chemotherapy has only limited activity. In cases where patients undergo resection before irradiation, intraoperative radiotherapy (IORT to the tumor bed may be an alternative modality, which would eliminate the repopulation of residual tumor cells between surgery and postoperative radiotherapy. Accumulating evidence has shown that high single doses of ionizing radiation can be highly efficient in eliciting a broad spectrum of local, regional, and systemic tumor-directed immune reactions. Furthermore, immune checkpoint blockade (ICB has proven effective in treating antigenic BM and, thus, combining IORT with ICB might be a promising approach. However, it is not known if a low number of residual tumor cells in the tumor bed after resection is sufficient to act as an immunizing event opening the gate for ICB therapies in the brain. Because immunological data on tumor bed irradiation after resection are lacking, a rationale for combining IORT with ICB must be based on mechanistic insight from experimental models and clinical studies on unresected tumors. The purpose of the present review is to examine the mechanisms by which large radiation doses as applied in SRS and IORT enhance antitumor immune activity. Clinical studies on IORT for brain tumors, and on combined treatment of SRS and ICB for unresected BM, are used to assess the safety, efficacy, and immunogenicity of IORT plus ICB and to suggest an optimal treatment sequence.

  5. Dermatologic radiotherapy and breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, H.; Gorson, R.O.; Lassen, M.

    1982-03-01

    This study was set up to provide quantitative data to evaluate unsubstantiated claims that improper dermatologic radiation techniques may cause breast cancer. A thin mylar window ionization rate meter placed at the location of the right breast of an Alderson-RANDO anthropomorphic phantom was used to measure direct and scatter radiation reaching the female breast during radiotherapy of the facial region (as given for acne). The results indicate that scatter doses are very small; they are influenced by radiation quality and the use or nonuse of a treatment cone. Quantitative risk estimates show that the very small risk of breast cancer induction can be reduced even further by the use of proper radiation protection measures.

  6. Tomodensitometry images: integration in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dessy, F.; Hoornaert, M.T. [Jolimont Hospital, Haine Saint Paul (France). Cancer and Nuclear Medicine Dept.; Malchair, F. [Biomed Engineering, Boncelles (France)

    1995-12-01

    With a view to utilization of CT scan images in radiotherapy, the effective energy and the linearity of four different scanners (Siemens somatom CR, HiQS, Plus and Picker PQ 2000) and two non standard scanners, simulators with CT option (Webb 1990) (Varian Ximatron and Oldelft Simulx CT) has been measured using the method described by White and Speller in 1980. When the linearity relation in presented using the density or the electron density as the abscissa, a blurred area where two different components of equal density or electron density can have two different Hounsfield`s numbers. Using the linearity relation, the density of Rando`s lung heterogeneity is determined. We calculated a treatment planning (TP) using this value and made a comparison between the TP and the real absorbed dose with was measured using diodes. The comparison between the TP and the relative Absorbed doses showed a difference of up to 4.5%.

  7. Radiogenomics and radiotherapy response modeling

    Science.gov (United States)

    El Naqa, Issam; Kerns, Sarah L.; Coates, James; Luo, Yi; Speers, Corey; West, Catharine M. L.; Rosenstein, Barry S.; Ten Haken, Randall K.

    2017-08-01

    Advances in patient-specific information and biotechnology have contributed to a new era of computational medicine. Radiogenomics has emerged as a new field that investigates the role of genetics in treatment response to radiation therapy. Radiation oncology is currently attempting to embrace these recent advances and add to its rich history by maintaining its prominent role as a quantitative leader in oncologic response modeling. Here, we provide an overview of radiogenomics starting with genotyping, data aggregation, and application of different modeling approaches based on modifying traditional radiobiological methods or application of advanced machine learning techniques. We highlight the current status and potential for this new field to reshape the landscape of outcome modeling in radiotherapy and drive future advances in computational oncology.

  8. Proposition of resolution tending to create an inquiry commission concerning the safety conditions of the radiotherapy practices; Proposition de resolution tendant a creer une commission d'enquete concernant les conditions de securite des pratiques de radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-10-15

    Towards the number of radiotherapy acts made every year and the increase of the number of the revealed accidents, it is absolutely indispensable to have an feedback experience and an assessment of the existing means today to control the radioprotection. This work has to allow to give propositions to improve the radiotherapy quality and safety, and provide the patients safety before, during and after the ionizing radiation exposure. (N.C.)

  9. P53 over-expression in laryngeal carcinoma is not predictive of response to radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tan, L.K.S. [University of Texas Medical Branch, Galveston, TX (United States). Dept. of Otolaryngology]|[National University Hospital, Singapore (Singapore); Ogden, G.R. [Dundee Univ. (United Kingdom). Dept. of Dental Surgery and Periodontology

    1997-05-01

    It has been suggested that alterations involving the p53 gene may influence tumour response to radiotherapy. p53 expression was assessed in 90 formalin-fixed paraffin-embedded laryngeal carcinoma that were subsequently treated with radiotherapy. The polyclonal antibody DO1 (1 in 50 dilution) was used, together with an avidin-biotin immunoperoxidase technique, but in the absence of any additional antigen retrieval techniques. p53 expression was assessed and correlated with various clinicopathological parameters. Using Chi square analysis, no significant difference between p53 positive and p53 negative lesions was found for response to radiotherapy, as measured by survival and recurrence rates. Furthermore, no correlation with p53 expression was found for tumour size, nodal metastasis, sex, age, alcohol intake, tobacco habit and histological grade. (author).

  10. Stereotactic body radiotherapy a practical guide

    CERN Document Server

    Gaya, Andrew

    2015-01-01

    Collecting the key information in this burgeoning field into a single volume, this handbook for clinical oncology trainees and consultants covers all of the basic aspects of stereotactic radiotherapy systems and treatment and includes plenty of case studies.

  11. Glioblastoma after radiotherapy for pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Young; Park, Kyung Ran; KIm, Jun Joo; Lee, Chong In; Kim, Myung Soon; Jung, Soon Hee [Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of)

    1999-12-01

    A 39-year-old woman developed a glioblastoma about 7 years and 10 months after local radiotherapy (45 Gy) for pituitary adenoma. Clinical and histopathological details are presented, and previously reported cases of radiation-induced glioma are reviewed.

  12. Estimating the Risks of Breast Cancer Radiotherapy

    DEFF Research Database (Denmark)

    Taylor, Carolyn; Correa, Candace; Duane, Frances K

    2017-01-01

    Purpose Radiotherapy reduces the absolute risk of breast cancer mortality by a few percentage points in suitable women but can cause a second cancer or heart disease decades later. We estimated the absolute long-term risks of modern breast cancer radiotherapy. Methods First, a systematic literature...... review was performed of lung and heart doses in breast cancer regimens published during 2010 to 2015. Second, individual patient data meta-analyses of 40,781 women randomly assigned to breast cancer radiotherapy versus no radiotherapy in 75 trials yielded rate ratios (RRs) for second primary cancers...... and cause-specific mortality and excess RRs (ERRs) per Gy for incident lung cancer and cardiac mortality. Smoking status was unavailable. Third, the lung or heart ERRs per Gy in the trials and the 2010 to 2015 doses were combined and applied to current smoker and nonsmoker lung cancer and cardiac mortality...

  13. MRI-guided radiotherapy for renal tumours

    NARCIS (Netherlands)

    Stam, M.K.

    2013-01-01

    The current surgical treatment for renal cell carcinoma (RCC) experiences complications due to the invasiveness of the treatment. Minimally invasive alternative treatments, such as radiofrequency and cryogen ablation, have fewer complications but a lower local control. Radiotherapy is an established

  14. The predicted relative risk of premature ovarian failure for three radiotherapy modalities in a girl receiving craniospinal irradiation.

    Science.gov (United States)

    Pérez-Andújar, A; Newhauser, W D; Taddei, P J; Mahajan, A; Howell, R M

    2013-05-21

    In girls and young women, irradiation of the ovaries can reduce the number of viable ovarian primordial follicles, which may lead to premature ovarian failure (POF) and subsequently to sterility. One strategy to minimize this late effect is to reduce the radiation dose to the ovaries. A primary means of reducing dose is to choose a radiotherapy technique that avoids irradiating nearby normal tissue; however, the relative risk of POF (RRPOF) due to the various therapeutic options has not been assessed. This study compared the predicted RRPOF after craniospinal proton radiotherapy, conventional photon radiotherapy (CRT) and intensity-modulated photon radiotherapy (IMRT). We calculated the equivalent dose delivered to the ovaries of an 11-year-old girl from therapeutic and stray radiation. We then predicted the percentage of ovarian primordial follicles killed by radiation and used this as a measure of the RRPOF; we also calculated the ratio of the relative risk of POF (RRRPOF) among the three radiotherapies. Proton radiotherapy had a lower RRPOF than either of the other two types. We also tested the sensitivity of the RRRPOF between photon and proton therapies to the anatomic position of the ovaries, i.e., proximity to the treatment field (2 ≤ RRRPOF ≤ 10). We found that CRT and IMRT have higher risks of POF than passive-scattering proton radiotherapy (PRT) does, regardless of uncertainties in the ovarian location. Overall, PRT represents a lower RRPOF over the two other modalities.

  15. The predicted relative risk of premature ovarian failure for three radiotherapy modalities in a girl receiving craniospinal irradiation

    Science.gov (United States)

    Pérez-Andújar, A.; Newhauser, W. D.; Taddei, P. J.; Mahajan, A.; Howell, R. M.

    2013-05-01

    In girls and young women, irradiation of the ovaries can reduce the number of viable ovarian primordial follicles, which may lead to premature ovarian failure (POF) and subsequently to sterility. One strategy to minimize this late effect is to reduce the radiation dose to the ovaries. A primary means of reducing dose is to choose a radiotherapy technique that avoids irradiating nearby normal tissue; however, the relative risk of POF (RRPOF) due to the various therapeutic options has not been assessed. This study compared the predicted RRPOF after craniospinal proton radiotherapy, conventional photon radiotherapy (CRT) and intensity-modulated photon radiotherapy (IMRT). We calculated the equivalent dose delivered to the ovaries of an 11-year-old girl from therapeutic and stray radiation. We then predicted the percentage of ovarian primordial follicles killed by radiation and used this as a measure of the RRPOF; we also calculated the ratio of the relative risk of POF (RRRPOF) among the three radiotherapies. Proton radiotherapy had a lower RRPOF than either of the other two types. We also tested the sensitivity of the RRRPOF between photon and proton therapies to the anatomic position of the ovaries, i.e., proximity to the treatment field (2 ≤ RRRPOF ≤ 10). We found that CRT and IMRT have higher risks of POF than passive-scattering proton radiotherapy (PRT) does, regardless of uncertainties in the ovarian location. Overall, PRT represents a lower RRPOF over the two other modalities.

  16. The result of radiotherapy for pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. J.; Yang, K. M.; Suh, S. H. [Inje Univ., Seoul (Korea,