WorldWideScience

Sample records for guided focused ultrasound

  1. CT and Ultrasound Guided Stereotactic High Intensity Focused Ultrasound (HIFU)

    Science.gov (United States)

    Wood, Bradford J.; Yanof, J.; Frenkel, V.; Viswanathan, A.; Dromi, S.; Oh, K.; Kruecker, J.; Bauer, C.; Seip, R.; Kam, A.; Li, K. C. P.

    2006-05-01

    animals and humans for HIFU-induced ablation and drug delivery. Integrated CT-guided focused ultrasound holds promise for tissue ablation, enhancing local drug delivery, and CT thermometry for monitoring ablation in near real-time.

  2. MR-guided focused ultrasound: a potentially disruptive technology.

    Science.gov (United States)

    Bradley, William G

    2009-07-01

    A disruptive technology is a technological innovation that overturns the existing dominant technologies in a market. Magnetic resonance (MR)-guided focused ultrasound (MRgFUS) is a noninvasive procedure based on the combination of real-time MR anatomic guidance, MR thermometry, and high-intensity focused ultrasound. Several hundred transducer elements become convergent at a point under MR guidance, leading to heating and coagulation necrosis. Outside the focal point, there is no significant heating. There is no need to break the skin for procedures in the body or to perform a craniotomy for procedures in the brain. This lack of invasiveness is what makes MRgFUS so disruptive compared with surgery. At present, MRgFUS has been used for the ablation of uterine fibroids, breast tumors, painful bony metastases, and liver tumors. In the brain, it has been used for the ablation of glioblastomas and for functional neurosurgery. Phantom and animal studies suggest future applications for prostate cancer and acute stroke treatment.

  3. MR-guided focused ultrasound surgery, present and future

    Energy Technology Data Exchange (ETDEWEB)

    Schlesinger, David, E-mail: djs9c@virginia.edu [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 and Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia 22908 (United States); Benedict, Stanley [Department of Radiation Oncology, University of California Davis, Davis, California 95817 (United States); Diederich, Chris [Department of Radiation Oncology, University of California San Francisco, San Francisco, California 94115 (United States); Gedroyc, Wladyslaw [Department of Medicine, Imperial College, London SW7 2AZ (United Kingdom); Klibanov, Alexander [Departments of Medicine, Cardiovascular Medicine, and Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908 (United States); Larner, James [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 (United States)

    2013-08-01

    MR-guided focused ultrasound surgery (MRgFUS) is a quickly developing technology with potential applications across a spectrum of indications traditionally within the domain of radiation oncology. Especially for applications where focal treatment is the preferred technique (for example, radiosurgery), MRgFUS has the potential to be a disruptive technology that could shift traditional patterns of care. While currently cleared in the United States for the noninvasive treatment of uterine fibroids and bone metastases, a wide range of clinical trials are currently underway, and the number of publications describing advances in MRgFUS is increasing. However, for MRgFUS to make the transition from a research curiosity to a clinical standard of care, a variety of challenges, technical, financial, clinical, and practical, must be overcome. This installment of the Vision 20/20 series examines the current status of MRgFUS, focusing on the hurdles the technology faces before it can cross over from a research technique to a standard fixture in the clinic. It then reviews current and near-term technical developments which may overcome these hurdles and allow MRgFUS to break through into clinical practice.

  4. MR-guided focused ultrasound surgery, present and future

    International Nuclear Information System (INIS)

    Schlesinger, David; Benedict, Stanley; Diederich, Chris; Gedroyc, Wladyslaw; Klibanov, Alexander; Larner, James

    2013-01-01

    MR-guided focused ultrasound surgery (MRgFUS) is a quickly developing technology with potential applications across a spectrum of indications traditionally within the domain of radiation oncology. Especially for applications where focal treatment is the preferred technique (for example, radiosurgery), MRgFUS has the potential to be a disruptive technology that could shift traditional patterns of care. While currently cleared in the United States for the noninvasive treatment of uterine fibroids and bone metastases, a wide range of clinical trials are currently underway, and the number of publications describing advances in MRgFUS is increasing. However, for MRgFUS to make the transition from a research curiosity to a clinical standard of care, a variety of challenges, technical, financial, clinical, and practical, must be overcome. This installment of the Vision 20/20 series examines the current status of MRgFUS, focusing on the hurdles the technology faces before it can cross over from a research technique to a standard fixture in the clinic. It then reviews current and near-term technical developments which may overcome these hurdles and allow MRgFUS to break through into clinical practice

  5. A long arm for ultrasound: a combined robotic focused ultrasound setup for magnetic resonance-guided focused ultrasound surgery.

    Science.gov (United States)

    Krafft, Axel J; Jenne, Jürgen W; Maier, Florian; Stafford, R Jason; Huber, Peter E; Semmler, Wolfhard; Bock, Michael

    2010-05-01

    Focused ultrasound surgery (FUS) is a highly precise noninvasive procedure to ablate pathogenic tissue. FUS therapy is often combined with magnetic resonance (MR) imaging as MR imaging offers excellent target identification and allows for continuous monitoring of FUS induced temperature changes. As the dimensions of the ultrasound (US) focus are typically much smaller than the targeted volume, multiple sonications and focus repositioning are interleaved to scan the focus over the target volume. Focal scanning can be achieved electronically by using phased-array US transducers or mechanically by using dedicated mechanical actuators. In this study, the authors propose and evaluate the precision of a combined robotic FUS setup to overcome some of the limitations of the existing MRgFUS systems. Such systems are typically integrated into the patient table of the MR scanner and thus only provide an application of the US wave within a limited spatial range from below the patient. The fully MR-compatible robotic assistance system InnoMotion (InnoMedic GmbH, Herxheim, Germany) was originally designed for MR-guided interventions with needles. It offers five pneumatically driven degrees of freedom and can be moved over a wide range within the bore of the magnet. In this work, the robotic system was combined with a fixed-focus US transducer (frequency: 1.7 MHz; focal length: 68 mm, and numerical aperture: 0.44) that was integrated into a dedicated, in-house developed treatment unit for FUS application. A series of MR-guided focal scanning procedures was performed in a polyacrylamide-egg white gel phantom to assess the positioning accuracy of the combined FUS setup. In animal experiments with a 3-month-old domestic pig, the system's potential and suitability for MRgFUS was tested. In phantom experiments, a total targeting precision of about 3 mm was found, which is comparable to that of the existing MRgFUS systems. Focus positioning could be performed within a few seconds

  6. Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain

    Science.gov (United States)

    Arvanitis, Costas D.; Livingstone, Margaret S.; McDannold, Nathan

    2013-07-01

    Several emerging therapies with potential for use in the brain, harness effects produced by acoustic cavitation—the interaction between ultrasound and microbubbles either generated during sonication or introduced into the vasculature. Systems developed for transcranial MRI-guided focused ultrasound (MRgFUS) thermal ablation can enable their clinical translation, but methods for real-time monitoring and control are currently lacking. Acoustic emissions produced during sonication can provide information about the location, strength and type of the microbubble oscillations within the ultrasound field, and they can be mapped in real-time using passive imaging approaches. Here, we tested whether such mapping can be achieved transcranially within a clinical brain MRgFUS system. We integrated an ultrasound imaging array into the hemisphere transducer of the MRgFUS device. Passive cavitation maps were obtained during sonications combined with a circulating microbubble agent at 20 targets in the cingulate cortex in three macaques. The maps were compared with MRI-evident tissue effects. The system successfully mapped microbubble activity during both stable and inertial cavitation, which was correlated with MRI-evident transient blood-brain barrier disruption and vascular damage, respectively. The location of this activity was coincident with the resulting tissue changes within the expected resolution limits of the system. While preliminary, these data clearly demonstrate, for the first time, that it is possible to construct maps of stable and inertial cavitation transcranially, in a large animal model, and under clinically relevant conditions. Further, these results suggest that this hybrid ultrasound/MRI approach can provide comprehensive guidance for targeted drug delivery via blood-brain barrier disruption and other emerging ultrasound treatments, facilitating their clinical translation. We anticipate that it will also prove to be an important research tool that will

  7. Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain

    International Nuclear Information System (INIS)

    Arvanitis, Costas D; McDannold, Nathan; Livingstone, Margaret S

    2013-01-01

    Several emerging therapies with potential for use in the brain, harness effects produced by acoustic cavitation—the interaction between ultrasound and microbubbles either generated during sonication or introduced into the vasculature. Systems developed for transcranial MRI-guided focused ultrasound (MRgFUS) thermal ablation can enable their clinical translation, but methods for real-time monitoring and control are currently lacking. Acoustic emissions produced during sonication can provide information about the location, strength and type of the microbubble oscillations within the ultrasound field, and they can be mapped in real-time using passive imaging approaches. Here, we tested whether such mapping can be achieved transcranially within a clinical brain MRgFUS system. We integrated an ultrasound imaging array into the hemisphere transducer of the MRgFUS device. Passive cavitation maps were obtained during sonications combined with a circulating microbubble agent at 20 targets in the cingulate cortex in three macaques. The maps were compared with MRI-evident tissue effects. The system successfully mapped microbubble activity during both stable and inertial cavitation, which was correlated with MRI-evident transient blood–brain barrier disruption and vascular damage, respectively. The location of this activity was coincident with the resulting tissue changes within the expected resolution limits of the system. While preliminary, these data clearly demonstrate, for the first time, that it is possible to construct maps of stable and inertial cavitation transcranially, in a large animal model, and under clinically relevant conditions. Further, these results suggest that this hybrid ultrasound/MRI approach can provide comprehensive guidance for targeted drug delivery via blood–brain barrier disruption and other emerging ultrasound treatments, facilitating their clinical translation. We anticipate that it will also prove to be an important research tool that

  8. Ultrasound guided supraclavicular block.

    LENUS (Irish Health Repository)

    Hanumanthaiah, Deepak

    2013-09-01

    Ultrasound guided regional anaesthesia is becoming increasingly popular. The supraclavicular block has been transformed by ultrasound guidance into a potentially safe superficial block. We reviewed the techniques of performing supraclavicular block with special focus on ultrasound guidance.

  9. Ultrasound-guided high-intensity focused ultrasound treatment for abdominal wall endometriosis: Preliminary results

    International Nuclear Information System (INIS)

    Wang Yang; Wang Wei; Wang Longxia; Wang Junyan; Tang Jie

    2011-01-01

    Purpose: To evaluate the safety and therapeutic efficacy of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation for the treatment of abdominal wall endometriosis (AWE). Materials and methods: Twenty-one consecutive patients with AWE were treated as outpatients by US-guided HIFU ablation under conscious sedation. The median size of the AWE was 2.4 cm (range 1.0-5.3 cm). An acoustic power of 200-420 W was used, intermittent HIFU exposure of 1 s was applied. Treatment was considered complete when the entire nodule and its nearby 1 cm margin become hyperechoic on US. Pain relief after HIFU ablation was observed and the treated nodule received serial US examinations during follow-up. Results: All AWE was successfully ablated after one session of HIFU ablation, the ablation time lasted for 5-48 min (median 13 min), no major complications occurred. The cyclic pain disappeared in all patients during a mean follow-up of 18.7 months (range 3-31 months). The treated nodules gradually shank over time, 16 nodules became unnoticeable on US during follow-up. Conclusion: US-guided HIFU ablation appears to be safe and effective for the treatment of AWE.

  10. Ultrasound-guided high-intensity focused ultrasound treatment for abdominal wall endometriosis: Preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yang [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Wang Wei, E-mail: wangyang301301@yahoo.com.cn [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China); Wang Longxia; Wang Junyan; Tang Jie [Department of Ultrasound, Chinese PLA General Hospital, 28 Fuxing Road, Beijing 100853 (China)

    2011-07-15

    Purpose: To evaluate the safety and therapeutic efficacy of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation for the treatment of abdominal wall endometriosis (AWE). Materials and methods: Twenty-one consecutive patients with AWE were treated as outpatients by US-guided HIFU ablation under conscious sedation. The median size of the AWE was 2.4 cm (range 1.0-5.3 cm). An acoustic power of 200-420 W was used, intermittent HIFU exposure of 1 s was applied. Treatment was considered complete when the entire nodule and its nearby 1 cm margin become hyperechoic on US. Pain relief after HIFU ablation was observed and the treated nodule received serial US examinations during follow-up. Results: All AWE was successfully ablated after one session of HIFU ablation, the ablation time lasted for 5-48 min (median 13 min), no major complications occurred. The cyclic pain disappeared in all patients during a mean follow-up of 18.7 months (range 3-31 months). The treated nodules gradually shank over time, 16 nodules became unnoticeable on US during follow-up. Conclusion: US-guided HIFU ablation appears to be safe and effective for the treatment of AWE.

  11. Review of magnetic resonance-guided focused ultrasound in the treatment of uterine fibroids

    Directory of Open Access Journals (Sweden)

    Pedro Felipe Magalhães Peregrino

    Full Text Available Uterine leiomyoma is the most frequently occurring solid pelvic tumor in women during the reproductive period. Magnetic resonance-guided high-intensity focused ultrasound is a promising technique for decreasing menorrhagia and dysmenorrhea in symptomatic women. The aim of this study is to review the role of Magnetic resonance-guided high-intensity focused ultrasound in the treatment of uterine fibroids in symptomatic patients. We performed a review of the MEDLINE and Cochrane databases up to April 2016. The analysis and data collection were performed using the following keywords: Leiomyoma, High-Intensity Focused Ultrasound Ablation, Ultrasonography, Magnetic Resonance Imaging, Menorrhagia. Two reviewers independently performed a quality assessment; when there was a disagreement, a third reviewer was consulted. Nineteen studies of Magnetic resonance-guided high-intensity focused ultrasound-treated fibroid patients were selected. The data indicated that tumor size was reduced and that symptoms were improved after treatment. There were few adverse effects, and they were not severe. Some studies have reported that in some cases, additional sessions of Magnetic resonance-guided high-intensity focused ultrasound or other interventions, such as myomectomy, uterine artery embolization or even hysterectomy, were necessary. This review suggests that Magnetic resonance-guided high-intensity focused ultrasound is a safe and effective technique. However, additional evidence from future studies will be required before the technique can be recommended as an alternative treatment for fibroids.

  12. MR-guided focused ultrasound. Current and future applications

    International Nuclear Information System (INIS)

    Trumm, C.G.; Peller, M.; Clevert, D.A.; Stahl, R.; Reiser, M.; Napoli, A.; Matzko, M.

    2013-01-01

    High-intensity focused ultrasound (synonyms FUS and HIFU) under magnetic resonance imaging (MRI) guidance (synonyms MRgFUS and MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. The combination of FUS with MRI for planning, (near) real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. The MRgFUS procedure is clinically established in particular for the treatment of symptomatic uterine fibroids, followed by palliative ablation of painful bone metastases. Furthermore, promising results have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier. (orig.) [de

  13. [MR-guided focused ultrasound. Current and future applications].

    Science.gov (United States)

    Trumm, C G; Napoli, A; Peller, M; Clevert, D-A; Stahl, R; Reiser, M; Matzko, M

    2013-03-01

    High-intensity focused ultrasound (synonyms FUS and HIFU) under magnetic resonance imaging (MRI) guidance (synonyms MRgFUS and MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. The combination of FUS with MRI for planning, (near) real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. The MRgFUS procedure is clinically established in particular for the treatment of symptomatic uterine fibroids, followed by palliative ablation of painful bone metastases. Furthermore, promising results have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier.

  14. MR-Guided Focused Ultrasound for the Treatment of Uterine Fibroids

    International Nuclear Information System (INIS)

    Hesley, Gina K.; Gorny, Krzysztof R.; Woodrum, David A.

    2013-01-01

    Magnetic resonance imaging–guided focused ultrasound (MRgFUS) ablation of uterine fibroids provides a minimally invasive outpatient technique for targeting and treating symptomatic uterine fibroids. Magnetic resonance imaging provides a guidance platform that has high temporal and spatial resolution for guiding, as well as thermal monitoring of the procedure. The high-intensity focused ultrasound provides a mechanism for delivering large amounts of energy directly into the fibroid without causing detrimental effects to the nontarget tissues. Early and intermediate follow-up of patients treated with MRgFUS provided promising results on the efficacy of the technique for providing symptom relief to patients. As more long-term follow-up data are published, the efficacy of this technique can be compared to more invasive surgical and minimally invasive catheter treatments.

  15. TU-B-210-00: MR-Guided Focused Ultrasound Therapy in Oncology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    MR guided focused ultrasound (MRgFUS), or alternatively high-intensity focused ultrasound (MRgHIFU), is approved for thermal ablative treatment of uterine fibroids and pain palliation in bone metastases. Ablation of malignant tumors is under active investigation in sites such as breast, prostate, brain, liver, kidney, pancreas, and soft tissue. Hyperthermia therapy with MRgFUS is also feasible, and may be used in conjunction with radiotherapy and for local targeted drug delivery. MRI allows in situ target definition and provides continuous temperature monitoring and subsequent thermal dose mapping during HIFU. Although MRgHIFU can be very precise, treatment of mobile organs is challenging and advanced techniques are required because of artifacts in MR temperature mapping, the need for intercostal firing, and need for gated HIFU or tracking of the lesion in real time. The first invited talk, “MR guided Focused Ultrasound Treatment of Tumors in Bone and Soft Tissue”, will summarize the treatment protocol and review results from treatment of bone tumors. In addition, efforts to extend this technology to treat both benign and malignant soft tissue tumors of the extremities will be presented. The second invited talk, “MRI guided High Intensity Focused Ultrasound – Advanced Approaches for Ablation and Hyperthermia”, will provide an overview of techniques that are in or near clinical trials for thermal ablation and hyperthermia, with an emphasis of applications in abdominal organs and breast, including methods for MRTI and tracking targets in moving organs. Learning Objectives: Learn background on devices and techniques for MR guided HIFU for cancer therapy Understand issues and current status of clinical MRg HIFU Understand strategies for compensating for organ movement during MRgHIFU Understand strategies for strategies for delivering hyperthermia with MRgHIFU CM - research collaboration with Philips.

  16. Magnetic resonance–guided interstitial high-intensity focused ultrasound for brain tumor ablation

    Science.gov (United States)

    MacDonell, Jacquelyn; Patel, Niravkumar; Rubino, Sebastian; Ghoshal, Goutam; Fischer, Gregory; Burdette, E. Clif; Hwang, Roy; Pilitsis, Julie G.

    2018-01-01

    Currently, treatment of brain tumors is limited to resection, chemotherapy, and radiotherapy. Thermal ablation has been recently explored. High-intensity focused ultrasound (HIFU) is being explored as an alternative. Specifically, the authors propose delivering HIFU internally to the tumor with an MRI-guided robotic assistant (MRgRA). The advantage of the authors’ interstitial device over external MRI-guided HIFU (MRgHIFU) is that it allows for conformal, precise ablation and concurrent tissue sampling. The authors describe their workflow for MRgRA HIFU delivery. PMID:29385926

  17. Feasibility of MRI-guided Focused Ultrasound as Organ-Sparing Treatment for Testicular Cancer

    Science.gov (United States)

    Staruch, Robert; Curiel, Laura; Chopra, Rajiv; Hynynen, Kullervo

    2009-04-01

    High cure rates for testicular cancer have prompted interest in organ-sparing surgery for patients with bilateral disease or single testis. Focused ultrasound (FUS) ablation could offer a noninvasive approach to organ-sparing surgery. The objective of this study was to determine the feasibility of using MR thermometry to guide organ-sparing focused ultrasound surgery in the testis. The testes of anesthetized rabbits were sonicated in several discrete locations using a single-element focused transducer operating at 2.787MHz. Focal heating was visualized with MR thermometry, using a measured PRF thermal coefficient of -0.0089±0.0003 ppm/° C. Sonications at 3.5-14 acoustic watts applied for 30 seconds produced maximum temperature elevations of 10-80° C, with coagulation verified by histology. Coagulation of precise volumes in the testicle is feasible with MRI-guided focused ultrasound. Variability in peak temperature for given sonication parameters suggests the need for online temperature feedback control.

  18. Optimizing MR imaging-guided navigation for focused ultrasound interventions in the brain

    Science.gov (United States)

    Werner, B.; Martin, E.; Bauer, R.; O'Gorman, R.

    2017-03-01

    MR imaging during transcranial MR imaging-guided Focused Ultrasound surgery (tcMRIgFUS) is challenging due to the complex ultrasound transducer setup and the water bolus used for acoustic coupling. Achievable image quality in the tcMRIgFUS setup using the standard body coil is significantly inferior to current neuroradiologic standards. As a consequence, MR image guidance for precise navigation in functional neurosurgical interventions using tcMRIgFUS is basically limited to the acquisition of MR coordinates of salient landmarks such as the anterior and posterior commissure for aligning a stereotactic atlas. Here, we show how improved MR image quality provided by a custom built MR coil and optimized MR imaging sequences can support imaging-guided navigation for functional tcMRIgFUS neurosurgery by visualizing anatomical landmarks that can be integrated into the navigation process to accommodate for patient specific anatomy.

  19. Noninvasive treatment of focal adenomyosis with MR-guided focused ultrasound in two patients

    International Nuclear Information System (INIS)

    Polina, Laveena; Nyapathy, Vinay; Mishra, Anindita; Yellamanthili, Himabindu; Vallabhaneni, Mythri P

    2012-01-01

    Adenomyosis is a common benign gynecological disorder presenting with dysmenorrhea, menorrhagia, and pressure symptoms. Magnetic resonance imaging–guided focused ultrasound surgery (MRgFUS) utilizes precisely focused USG waves to generate and maintain high temperatures within the targeted tissue to achieve protein denaturation and coagulative necrosis. The heat generated is monitored using MRI images acquired in real-time in three planes. We present two cases of focal adenomyosis treated with MRgFUS showing good symptomatic relief at 3 and 6 months follow-up

  20. NMR guided focused ultrasound for myoma therapy - results from the first radiology-gynecology expert meeting

    International Nuclear Information System (INIS)

    Beck, A.; Charite Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Berlin; David, M.; Kroencke, T.; Charite Universitaetsmedizin Berlin, Campus Charite Mitte, Berlin

    2013-01-01

    The contribution on the results from the first radiology-gynecology expert meeting concerning NMR guided focused ultrasound (MRgFUS) for myoma therapy covers the following topics: structural prerequisites for MRgFUS therapy; required examinations before MRgFUS therapy; indication for MRgFUS therapy; success criteria for the MRgFUS therapy; contraindications; MRgFUS therapy for patients that want to have children; side effects and complications of MRgFUS therapy; post-examination after MRgFUS therapy.

  1. MRI-Guided Focused Ultrasound as a New Method of Drug Delivery

    Directory of Open Access Journals (Sweden)

    M. Thanou

    2013-01-01

    Full Text Available Ultrasound-mediated drug delivery under the guidance of an imaging modality can improve drug disposition and achieve site-specific drug delivery. The term focal drug delivery has been introduced to describe the focal targeting of drugs in tissues with the help of imaging and focused ultrasound. Focal drug delivery aims to improve the therapeutic profile of drugs by improving their specificity and their permeation in defined areas. Focused-ultrasound- (FUS- mediated drug delivery has been applied with various molecules to improve their local distribution in tissues. FUS is applied with the aid of microbubbles to enhance the permeability of bioactive molecules across BBB and improve drug distribution in the brain. Recently, FUS has been utilised in combination with MRI-labelled liposomes that respond to temperature increase. This strategy aims to “activate” nanoparticles to release their cargo locally when triggered by hyperthermia induced by FUS. MRI-guided FUS drug delivery provides the opportunity to improve drug bioavailability locally and therefore improve the therapeutic profiles of drugs. This drug delivery strategy can be directly translated to clinic as MRg FUS is a promising clinically therapeutic approach. However, more basic research is required to understand the physiological mechanism of FUS-enhanced drug delivery.

  2. Endogenous Catalytic Generation of O2 Bubbles for In Situ Ultrasound-Guided High Intensity Focused Ultrasound Ablation.

    Science.gov (United States)

    Liu, Tianzhi; Zhang, Nan; Wang, Zhigang; Wu, Meiying; Chen, Yu; Ma, Ming; Chen, Hangrong; Shi, Jianlin

    2017-09-26

    High intensity focused ultrasound (HIFU) surgery generally suffers from poor precision and low efficiency in clinical application, especially for cancer therapy. Herein, a multiscale hybrid catalytic nanoreactor (catalase@MONs, abbreviated as C@M) has been developed as a tumor-sensitive contrast and synergistic agent (C&SA) for ultrasound-guided HIFU cancer surgery, by integrating dendritic-structured mesoporous organosilica nanoparticles (MONs) and catalase immobilized in the large open pore channels of MONs. Such a hybrid nanoreactor exhibited sensitive catalytic activity toward H 2 O 2 , facilitating the continuous O 2 gas generation in a relatively mild manner even if incubated with 10 μM H 2 O 2 , which finally led to enhanced ablation in the tissue-mimicking PAA gel model after HIFU exposure mainly resulting from intensified cavitation effect. The C@M nanoparticles could be accumulated within the H 2 O 2 -enriched tumor region through enhanced permeability and retention effect, enabling durable contrast enhancement of ultrasound imaging, and highly efficient tumor ablation under relatively low power of HIFU exposure in vivo. Very different from the traditional perfluorocarbon-based C&SA, such an on-demand catalytic nanoreactor could realize the accurate positioning of tumor without HIFU prestimulation and efficient HIFU ablation with a much safer power output, which is highly desired in clinical HIFU application.

  3. Magnetic Resonance-Guided High-Intensity-Focused Ultrasound for Palliation of Painful Skeletal Metastases: A Pilot Study.

    Science.gov (United States)

    Chan, Michael; Dennis, Kristopher; Huang, Yuexi; Mougenot, Charles; Chow, Edward; DeAngelis, Carlo; Coccagna, Jennifer; Sahgal, Arjun; Hynynen, Kullervo; Czarnota, Gregory; Chu, William

    2017-10-01

    Bone is one of the most common sites of metastases, with bone metastases-related pain representing a significant source of morbidity among patients with cancer. Magnetic resonance-guided focused ultrasound is a noninvasive, outpatient modality with the potential for treating painful bone metastases. The aim of this study is to report our initial experience with magnetic resonance-guided focused ultrasound in the treatment of bone metastases and our preliminary analysis of urinary cytokine levels after therapy. This was a single-center pilot study of 10 patients with metastatic cancer to investigate the feasibility of magnetic resonance-guided focused ultrasound for primary pain control in device-accessible skeletal metastases. Treatments were performed on a clinical magnetic resonance-guided focused ultrasound system using a volumetric ablation technique. Primary efficacy was assessed using Brief Pain Inventory scores and morphine equivalent daily dose intake at 3 time points: before, day 14, and day 30 after the magnetic resonance-guided focused ultrasound treatment. Urine cytokines were measured 3 days before treatment and 2 days after the treatment. Of the 10 patients, 8 were followed up 14 days and 6 were followed up 30 days after the treatment. At day 14, 3 patients (37.5%) exhibited partial pain response and 4 patients (50%) exhibited an indeterminate response, and at day 30 after the treatment, 5 patients (83%) exhibited partial pain response. No treatment-related adverse events were recorded. Of the urine cytokines measured, only Transforming growth factor alpha (TGFα) demonstrated an overall decrease, with a trend toward statistical significance ( P = .078). Our study corroborates magnetic resonance-guided focused ultrasound as a feasible and safe modality as a primary, palliative treatment for painful bone metastases and contributes to the limited body of literature using magnetic resonance-guided focused ultrasound for this clinical indication.

  4. Image-guided focused ultrasound ablation of breast cancer: current status, challenges, and future directions

    NARCIS (Netherlands)

    Schmitz, A.C.; Gianfelice, D.; Daniel, B.L.; Mali, W.P.T.M.; Bosch, M.A.A.J. van den

    2008-01-01

    Image-guided focussed ultrasound (FUS) ablation is a noninvasive procedure that has been used for treatment of benign or malignant breast tumours. Image-guidance during ablation is achieved either by using real-time ultrasound (US) or magnetic resonance imaging (MRI). The past decade phase I

  5. Power cavitation-guided blood-brain barrier opening with focused ultrasound and microbubbles

    Science.gov (United States)

    Burgess, M. T.; Apostolakis, I.; Konofagou, E. E.

    2018-03-01

    Image-guided monitoring of microbubble-based focused ultrasound (FUS) therapies relies on the accurate localization of FUS-stimulated microbubble activity (i.e. acoustic cavitation). Passive cavitation imaging with ultrasound arrays can achieve this, but with insufficient spatial resolution. In this study, we address this limitation and perform high-resolution monitoring of acoustic cavitation-mediated blood-brain barrier (BBB) opening with a new technique called power cavitation imaging. By synchronizing the FUS transmit and passive receive acquisition, high-resolution passive cavitation imaging was achieved by using delay and sum beamforming with absolute time delays. Since the axial image resolution is now dependent on the duration of the received acoustic cavitation emission, short pulses of FUS were used to limit its duration. Image sets were acquired at high-frame rates for calculation of power cavitation images analogous to power Doppler imaging. Power cavitation imaging displays the mean intensity of acoustic cavitation over time and was correlated with areas of acoustic cavitation-induced BBB opening. Power cavitation-guided BBB opening with FUS could constitute a standalone system that may not require MRI guidance during the procedure. The same technique can be used for other acoustic cavitation-based FUS therapies, for both safety and guidance.

  6. Magnetic Resonance Imaging-Guided Focused Ultrasound Surgery for the Treatment of Symptomatic Uterine Fibroids

    Directory of Open Access Journals (Sweden)

    Laura Geraci

    2017-01-01

    Full Text Available Uterine fibroids, the most common benign tumor in women of childbearing age, may cause symptoms including pelvic pain, menorrhagia, dysmenorrhea, pressure, urinary symptoms, and infertility. Various approaches are available to treat symptomatic uterine fibroids. Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS represents a recently introduced noninvasive safe and effective technique that can be performed without general anesthesia, in an outpatient setting. We review the principles of MRgFUS, describing patient selection criteria for the treatments performed at our center and we present a series of five selected patients with symptomatic uterine fibroids treated with this not yet widely known technique, showing its efficacy in symptom improvement and fibroid volume reduction.

  7. Magnetic Resonance Imaging-Guided Focused Ultrasound Surgery for the Treatment of Symptomatic Uterine Fibroids.

    Science.gov (United States)

    Geraci, Laura; Napoli, Alessandro; Catalano, Carlo; Midiri, Massimo; Gagliardo, Cesare

    2017-01-01

    Uterine fibroids, the most common benign tumor in women of childbearing age, may cause symptoms including pelvic pain, menorrhagia, dysmenorrhea, pressure, urinary symptoms, and infertility. Various approaches are available to treat symptomatic uterine fibroids. Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) represents a recently introduced noninvasive safe and effective technique that can be performed without general anesthesia, in an outpatient setting. We review the principles of MRgFUS, describing patient selection criteria for the treatments performed at our center and we present a series of five selected patients with symptomatic uterine fibroids treated with this not yet widely known technique, showing its efficacy in symptom improvement and fibroid volume reduction.

  8. Magnetic resonance imaging-guided focused ultrasound to increase localized blood-spinal cord barrier permeability.

    Science.gov (United States)

    Payne, Allison H; Hawryluk, Gregory W; Anzai, Yoshimi; Odéen, Henrik; Ostlie, Megan A; Reichert, Ethan C; Stump, Amanda J; Minoshima, Satoshi; Cross, Donna J

    2017-12-01

    Spinal cord injury (SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound (MRgFUS) as a non-invasive approach to increase permeability in the blood-spinal cord barrier (BSCB). We hypothesize that localized, controlled sonoporation of the BSCB by MRgFUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRgFUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRgFUS blood spinal cord barrier opening. Then, in normal rats, MRgFUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.

  9. Feasibility of MRI-guided high intensity focused ultrasound treatment for adenomyosis

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Tien-Ying [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Zhang, Lian; Chen, Wenzhi [Clinical Center of Tumor Therapy of 2nd Affiliated Hospital of Chongqing Medical University, Chongqing 400010 (China); Liu, Yinjiang; He, Min; Huang, Xiu [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Orsi, Franco [Interventional Radiology Unit, European Institute of Oncology, 435 Via Ripamonti, 20141 Milan (Italy); Wang, Zhibiao, E-mail: wangzhibiao@haifu.com.cn [State Key Laboratory of Ultrasound Engineering in Medicine, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Clinical Center of Tumor Therapy of 2nd Affiliated Hospital of Chongqing Medical University, Chongqing 400010 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer We tested the feasibility of MRIgHIFU ablation for adenomyosis. Black-Right-Pointing-Pointer Patients were treated with MRIgHIFU under conscious sedation. Black-Right-Pointing-Pointer Patient symptoms were assessed using SSS and UFS-QOL. Black-Right-Pointing-Pointer The mean SSS and UFS-QOL showed significant improvements at follow up. Black-Right-Pointing-Pointer No serious complications were observed 62.5 {+-} 21.6. -- Abstract: Purpose: To test the feasibility of MRI-guided high intensity focused ultrasound ablation for adenomyosis. Materials and methods: Patients with symptomatic adenomyosis were treated with MRI-guided high intensity focused ultrasound (MRIgHIFU). Under conscious sedation, MRIgHIFU was performed by a clinical MRI-compatible focused ultrasound tumour therapeutic system (JM15100, Haifu{sup Registered-Sign} Technology Co. Ltd., Chongqing, China) which is combined with a 1.5 T MRI system (Magnetom Symphony, Siemens Healthcare, Erlangen, Germany). MRI was used to calculate the volume of the uterus and lesion. Non-perfused volume of the targeted lesions was evaluated immediately after MRIgHIFU. Patient symptoms were assessed using symptom severity score (SSS) and uterine fibroids symptoms and quality of life questionnaire (UFS-QOL). Results: Ten patients with mean age of 40.3 {+-} 4 years with an average lesion size of 56.9 {+-} 12.7 mm in diameter were treated. Non-perfused volume and the percentage of non-perfused volume obtained from contrast-enhanced T1 Magnetic resonance images immediately post-treatment were 66.6 {+-} 49.4 cm{sup 3} and 62.5 {+-} 21.6%, respectively. The mean SSS and UFS-QOL showed significant improvements of 25%, 16% and 25% at 3, 6 and 12 months follow up, respectively, to pre-treatment scores. No serious complications were observed. Conclusion: Based on the results from this study, MRIgHIFU treatment appears to be a safe and feasible modality to ablate adenomyosis lesion and

  10. MO-DE-202-01: Image-Guided Focused Ultrasound Surgery and Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, K. [National Cancer Institute (United States)

    2016-06-15

    At least three major trends in surgical intervention have emerged over the last decade: a move toward more minimally invasive (or non-invasive) approach to the surgical target; the development of high-precision treatment delivery techniques; and the increasing role of multi-modality intraoperative imaging in support of such procedures. This symposium includes invited presentations on recent advances in each of these areas and the emerging role for medical physics research in the development and translation of high-precision interventional techniques. The four speakers are: Keyvan Farahani, “Image-guided focused ultrasound surgery and therapy” Jeffrey H. Siewerdsen, “Advances in image registration and reconstruction for image-guided neurosurgery” Tina Kapur, “Image-guided surgery and interventions in the advanced multimodality image-guided operating (AMIGO) suite” Raj Shekhar, “Multimodality image-guided interventions: Multimodality for the rest of us” Learning Objectives: Understand the principles and applications of HIFU in surgical ablation. Learn about recent advances in 3D–2D and 3D deformable image registration in support of surgical safety and precision. Learn about recent advances in model-based 3D image reconstruction in application to intraoperative 3D imaging. Understand the multi-modality imaging technologies and clinical applications investigated in the AMIGO suite. Understand the emerging need and techniques to implement multi-modality image guidance in surgical applications such as neurosurgery, orthopaedic surgery, vascular surgery, and interventional radiology. Research supported by the NIH and Siemens Healthcare.; J. Siewerdsen; Grant Support - National Institutes of Health; Grant Support - Siemens Healthcare; Grant Support - Carestream Health; Advisory Board - Carestream Health; Licensing Agreement - Carestream Health; Licensing Agreement - Elekta Oncology.; T. Kapur, P41EB015898; R. Shekhar, Funding: R42CA137886 and R41CA192504

  11. MO-DE-202-01: Image-Guided Focused Ultrasound Surgery and Therapy

    International Nuclear Information System (INIS)

    Farahani, K.

    2016-01-01

    At least three major trends in surgical intervention have emerged over the last decade: a move toward more minimally invasive (or non-invasive) approach to the surgical target; the development of high-precision treatment delivery techniques; and the increasing role of multi-modality intraoperative imaging in support of such procedures. This symposium includes invited presentations on recent advances in each of these areas and the emerging role for medical physics research in the development and translation of high-precision interventional techniques. The four speakers are: Keyvan Farahani, “Image-guided focused ultrasound surgery and therapy” Jeffrey H. Siewerdsen, “Advances in image registration and reconstruction for image-guided neurosurgery” Tina Kapur, “Image-guided surgery and interventions in the advanced multimodality image-guided operating (AMIGO) suite” Raj Shekhar, “Multimodality image-guided interventions: Multimodality for the rest of us” Learning Objectives: Understand the principles and applications of HIFU in surgical ablation. Learn about recent advances in 3D–2D and 3D deformable image registration in support of surgical safety and precision. Learn about recent advances in model-based 3D image reconstruction in application to intraoperative 3D imaging. Understand the multi-modality imaging technologies and clinical applications investigated in the AMIGO suite. Understand the emerging need and techniques to implement multi-modality image guidance in surgical applications such as neurosurgery, orthopaedic surgery, vascular surgery, and interventional radiology. Research supported by the NIH and Siemens Healthcare.; J. Siewerdsen; Grant Support - National Institutes of Health; Grant Support - Siemens Healthcare; Grant Support - Carestream Health; Advisory Board - Carestream Health; Licensing Agreement - Carestream Health; Licensing Agreement - Elekta Oncology.; T. Kapur, P41EB015898; R. Shekhar, Funding: R42CA137886 and R41CA192504

  12. Theranostic Gd(III)-lipid microbubbles for MRI-guided focused ultrasound surgery.

    Science.gov (United States)

    Feshitan, Jameel A; Vlachos, Fotis; Sirsi, Shashank R; Konofagou, Elisa E; Borden, Mark A

    2012-01-01

    We have synthesized a biomaterial consisting of Gd(III) ions chelated to lipid-coated, size-selected microbubbles for utility in both magnetic resonance and ultrasound imaging. The macrocyclic ligand DOTA-NHS was bound to PE headgroups on the lipid shell of pre-synthesized microbubbles. Gd(III) was then chelated to DOTA on the microbubble shell. The reaction temperature was optimized to increase the rate of Gd(III) chelation while maintaining microbubble stability. ICP-OES analysis of the microbubbles determined a surface density of 7.5 × 10(5) ± 3.0 × 10(5) Gd(III)/μm(2) after chelation at 50 °C. The Gd(III)-bound microbubbles were found to be echogenic in vivo during high-frequency ultrasound imaging of the mouse kidney. The Gd(III)-bound microbubbles also were characterized by magnetic resonance imaging (MRI) at 9.4 T by a spin-echo technique and, surprisingly, both the longitudinal and transverse proton relaxation rates were found to be roughly equal to that of no-Gd(III) control microbubbles and saline. However, the relaxation rates increased significantly, and in a dose-dependent manner, after sonication was used to fragment the Gd(III)-bound microbubbles into non-gas-containing lipid bilayer remnants. The longitudinal (r(1)) and transverse (r(2)) molar relaxivities were 4.0 ± 0.4 and 120 ± 18 mM(-1)s(-1), respectively, based on Gd(III) content. The Gd(III)-bound microbubbles may find application in the measurement of cavitation events during MRI-guided focused ultrasound therapy and to track the biodistribution of shell remnants. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Focal point determination in magnetic resonance-guided focused ultrasound using tracking coils.

    Science.gov (United States)

    Svedin, Bryant T; Beck, Michael J; Hadley, J Rock; Merrill, Robb; de Bever, Joshua T; Bolster, Bradley D; Payne, Allison; Parker, Dennis L

    2017-06-01

    To develop a method for rapid prediction of the geometric focus location in MR coordinates of a focused ultrasound (US) transducer with arbitrary position and orientation without sonicating. Three small tracker coil circuits were designed, constructed, attached to the transducer housing of a breast-specific MR-guided focused US (MRgFUS) system with 5 degrees of freedom, and connected to receiver channel inputs of an MRI scanner. A one-dimensional sequence applied in three orthogonal directions determined the position of each tracker, which was then corrected for gradient nonlinearity. In a calibration step, low-level heating located the US focus in one transducer position orientation where the tracker positions were also known. Subsequent US focus locations were determined from the isometric transformation of the trackers. The accuracy of this method was verified by comparing the tracking coil predictions to thermal center of mass calculated using MR thermometry data acquired at 16 different transducer positions for MRgFUS sonications in a homogeneous gelatin phantom. The tracker coil predicted focus was an average distance of 2.1 ± 1.1 mm from the thermal center of mass. The one-dimensional locator sequence and prediction calculations took less than 1 s to perform. This technique accurately predicts the geometric focus for a transducer with arbitrary position and orientation without sonicating. Magn Reson Med 77:2424-2430, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  14. Feasibility of ultrasound-guided high intensity focused ultrasound ablating uterine fibroids with hyperintense on T2-weighted MR imaging

    International Nuclear Information System (INIS)

    Zhao, Wen-Peng; Chen, Jin-Yun; Zhang, Lian; Li, Quan; Qin, Juan

    2013-01-01

    Purpose: To retrospectively investigate whether uterine fibroids with hyperintense on pretreatment T2-weighted magnetic resonance imaging (MRI) could be treated with ultrasound-guided high intensity focused ultrasound (USgHIFU). Materials and methods: 282 patients with 282 symptomatic uterine fibroids who underwent USgHIFU treatment were retrospectively analyzed. Based on the signal intensity of T2-weighted MRI, uterine fibroids were classified as hypointense, isointense and hyperintense. Hyperintense fibroids were subjectively further subdivided into heterogeneous hyperintense, slightly homogeneous hyperintense and markedly homogeneous hyperintense based on the signal intensity of fibroid relative to myometrium and endometrium on T2-weighted MRI. Enhanced MRI was performed within one month after HIFU treatment. Non-perfused volume (NPV, indicative of successful ablation) ratio, treatment time, treatment efficiency, energy effect ratio and adverse events were recorded. Results: The median volume of uterine fibroids was 70.3 cm 3 (interquartile range, 41.1–132.5 cm 3 ). The average NPV ratio, defined as non-perfused volume divided by the fibroid volume after HIFU treatment, was 76.8 ± 19.0% (range, 0–100%) in the 282 patients. It was 86.3 ± 11.9% (range, 40.9–100.0%) in the group with hypointense fibroids, 77.1 ± 16.5% (range, 32.2–100.0%) in isointense fibroids, and 67.6 ± 23.9% (range, 0–100.0%) in hyperintense fibroids. The lowest NPV ratio, lowest treatment efficiency, more treatment time, more sonication energy and pain scores were observed in the slightly homogeneous hyperintense fibroids, and the NPV ratio was 55.8 ± 26.7% (range, 0–83.9%) in this subgroup. Conclusion: Based on our results, the heterogeneous and markedly homogeneous hyperintense fibroids were suitable for USgHIFU, and only the slightly homogeneous hyperintense fibroids should be excluded

  15. A framework for continuous target tracking during MR-guided high intensity focused ultrasound thermal ablations in the abdomen

    NARCIS (Netherlands)

    Zachiu, Cornel; Denis de Senneville, Baudouin; Dmitriev, Ivan D.; Moonen, Chrit T.W.; Ries, Mario

    2017-01-01

    Background: During lengthy magnetic resonance-guided high intensity focused ultrasound (MRg-HIFU) thermal ablations in abdominal organs, the therapeutic work-flow is frequently hampered by various types of physiological motion occurring at different time-scales. If left un-addressed this can lead to

  16. Histopathology of breast cancer after magnetic resonance-guided high-intensity focused ultrasound and radiofrequency ablation

    NARCIS (Netherlands)

    Knuttel, Floor; Waaijer, Laurien; Merckel, LG; van den Bosch, Maurice A A J; Witkamp, Arjen J.; Deckers, Roel; van Diest, Paul J.

    AIMS: Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation and radiofrequency ablation (RFA) are being researched as possible substitutes for surgery in breast cancer patients. The histopathological appearance of ablated tissue has not been studied in great detail. This

  17. Effects of magnetic resonance-guided high-intensity focused ultrasound ablation on bone mechanical properties and modeling

    NARCIS (Netherlands)

    Yeoh, S.Y.; Arias Moreno, A.J.; Rietbergen, van B.; Hoeve, ter N.D.; Diest, van P.J.; Grull, H.

    2015-01-01

    Background Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is a promising technique for palliative treatment of bone pain. In this study, the effects of MR-HIFU ablation on bone mechanics and modeling were investigated. Methods A total of 12 healthy rat femurs were ablated

  18. Open-source, small-animal magnetic resonance-guided focused ultrasound system.

    Science.gov (United States)

    Poorman, Megan E; Chaplin, Vandiver L; Wilkens, Ken; Dockery, Mary D; Giorgio, Todd D; Grissom, William A; Caskey, Charles F

    2016-01-01

    MR-guided focused ultrasound or high-intensity focused ultrasound (MRgFUS/MRgHIFU) is a non-invasive therapeutic modality with many potential applications in areas such as cancer therapy, drug delivery, and blood-brain barrier opening. However, the large financial costs involved in developing preclinical MRgFUS systems represent a barrier to research groups interested in developing new techniques and applications. We aim to mitigate these challenges by detailing a validated, open-source preclinical MRgFUS system capable of delivering thermal and mechanical FUS in a quantifiable and repeatable manner under real-time MRI guidance. A hardware and software package was developed that includes closed-loop feedback controlled thermometry code and CAD drawings for a therapy table designed for a preclinical MRI scanner. For thermal treatments, the modular software uses a proportional integral derivative controller to maintain a precise focal temperature rise in the target given input from MR phase images obtained concurrently. The software computes the required voltage output and transmits it to a FUS transducer that is embedded in the delivery table within the magnet bore. The delivery table holds the FUS transducer, a small animal and its monitoring equipment, and a transmit/receive RF coil. The transducer is coupled to the animal via a water bath and is translatable in two dimensions from outside the magnet. The transducer is driven by a waveform generator and amplifier controlled by real-time software in Matlab. MR acoustic radiation force imaging is also implemented to confirm the position of the focus for mechanical and thermal treatments. The system was validated in tissue-mimicking phantoms and in vivo during murine tumor hyperthermia treatments. Sonications were successfully controlled over a range of temperatures and thermal doses for up to 20 min with minimal temperature overshoot. MR thermometry was validated with an optical temperature probe, and focus

  19. Does the phase of menstrual cycle affect MR-guided focused ultrasound surgery of uterine leiomyomas?

    International Nuclear Information System (INIS)

    So, Minna J.; Fennessy, Fiona M.; Zou, Kelly H.; McDannold, Nathan; Hynynen, Kullervo; Jolesz, Ferenc A.; Stewart, Elizabeth A.; Rybicki, Frank J.; Tempany, Clare M.

    2006-01-01

    Purpose: To determine whether the phase of menstrual cycle at the time of MR-guided focused ultrasound surgery (MRgFUS) treatment for uterine leiomyomas affects treatment outcome. Methods: We enrolled all patients participating in a prospective phase III clinical trial from our center who completed 6 months of clinical and imaging follow-up. Patients with irregular cycles and those on oral contraceptives were excluded. Data prospectively documenting the date of the last menstrual period (LMP) at the time of treatment, length and duration of cycle, and raw symptom severity score (SSS) from the Uterine Fibroid Symptom and Quality of Life questionnaire, at baseline and 6 months were collected. Proliferative phase patients were determined retrospectively as those who were treated within less than 14 days from LMP; secretory phase patients were classified as those who were treated greater than 14 days from LMP. Results: A total of 58 patients were enrolled. There was no significant difference in the mean SSS at baseline and mean SSS at 6 months between patients treated in the proliferative versus secretory phase of the cycle. No significant difference in the SSS change from baseline to 6 months was seen between the two groups. Conclusions: Menstrual cycle phase does not influence MRgFUS treatment outcome. Symptomatic improvement occurs with treatment during either phase of the menstrual cycle. Thus, the scheduling of MRgFUS treatment need not be based upon the phase of the menstrual cycle

  20. MRI-guided focused ultrasound thalamotomy in non-ET tremor syndromes.

    Science.gov (United States)

    Fasano, Alfonso; Llinas, Maheleth; Munhoz, Renato P; Hlasny, Eugen; Kucharczyk, Walter; Lozano, Andres M

    2017-08-22

    To report the 6-month single-blinded results of unilateral thalamotomy with MRI-guided focused ultrasound (MRgFUS) in patients with tremors other than essential tremor. Three patients with tremor due to Parkinson disease, 2 with dystonic tremor in the context of cervicobrachial dystonia and writer's cramp, and 1 with dystonia gene-associated tremor underwent MRgFUS targeting the ventro-intermedius nucleus (Vim) of the dominant hemisphere. The primary endpoint was the reduction of lateralized items of the Tremor Rating Scale of contralateral hemibody assessed by a blinded rater. All patients achieved a statistically significant, immediate, and sustained improvement of the contralateral tremor score by 42.2%, 52.0%, 55.9%, and 52.9% at 1 week and 1, 3, and 6 months after the procedure, respectively. All patients experienced transient side effects and 2 patients experienced persistent side effects at the time of last evaluation: hemitongue numbness and hemiparesis with hemihypoesthesia. Vim MRgFUS is a promising, incision-free, but nevertheless invasive technique to effectively treat tremors other than essential tremor. Future studies on larger samples and longer follow-up will further define its effectiveness and safety. NCT02252380. This study provides Class IV evidence that for patients with tremor not caused by essential tremor, MRgFUS of the Vim improves the tremor of the contralateral hemibody at 6 months. © 2017 American Academy of Neurology.

  1. Does the phase of menstrual cycle affect MR-guided focused ultrasound surgery of uterine leiomyomas?

    Energy Technology Data Exchange (ETDEWEB)

    So, Minna J. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Fennessy, Fiona M. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Zou, Kelly H. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); McDannold, Nathan [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Hynynen, Kullervo [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Jolesz, Ferenc A. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Stewart, Elizabeth A. [Department of Obstetrics and Gynecology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Rybicki, Frank J. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States); Tempany, Clare M. [Department of Radiology, Brigham and Women' s Hospital/Harvard Medical School, Boston, MA (United States)]. E-mail: ctempanyafdhal@partners.org

    2006-08-15

    Purpose: To determine whether the phase of menstrual cycle at the time of MR-guided focused ultrasound surgery (MRgFUS) treatment for uterine leiomyomas affects treatment outcome. Methods: We enrolled all patients participating in a prospective phase III clinical trial from our center who completed 6 months of clinical and imaging follow-up. Patients with irregular cycles and those on oral contraceptives were excluded. Data prospectively documenting the date of the last menstrual period (LMP) at the time of treatment, length and duration of cycle, and raw symptom severity score (SSS) from the Uterine Fibroid Symptom and Quality of Life questionnaire, at baseline and 6 months were collected. Proliferative phase patients were determined retrospectively as those who were treated within less than 14 days from LMP; secretory phase patients were classified as those who were treated greater than 14 days from LMP. Results: A total of 58 patients were enrolled. There was no significant difference in the mean SSS at baseline and mean SSS at 6 months between patients treated in the proliferative versus secretory phase of the cycle. No significant difference in the SSS change from baseline to 6 months was seen between the two groups. Conclusions: Menstrual cycle phase does not influence MRgFUS treatment outcome. Symptomatic improvement occurs with treatment during either phase of the menstrual cycle. Thus, the scheduling of MRgFUS treatment need not be based upon the phase of the menstrual cycle.

  2. Positioning device for MRI-guided high intensity focused ultrasound system

    Energy Technology Data Exchange (ETDEWEB)

    Damianou, Christakis [Frederick Institute of Technology (FIT), Limassol (Cyprus); MEDSONIC, LTD, Limassol (Cyprus); Ioannides, Kleanthis [Polikliniki Igia, Limassol (Cyprus); Milonas, Nicos [Frederick Institute of Technology (FIT), Limassol (Cyprus)

    2008-04-15

    A prototype magnetic resonance imaging (MRI)- compatible positioning device was used to move an MRI-guided high intensity focused ultrasound (HIFU) transducer. The positioning device has three user-controlled degrees of freedom that allow access to various targeted lesions. The positioning device was designed and fabricated using construction materials selected for compatibility with high magnetic fields and fast switching magnetic field gradients encountered inside MRI scanners. The positioning device incorporates only MRI compatible materials such as piezoelectric motors, plastic sheets, brass screws, plastic pulleys and timing belts. The HIFU/MRI system includes the multiple subsystems (a) HIFU system, (b) MR imaging, (c) Positioning device (robot) and associate drivers, (d) temperature measurement, (e) cavitation detection, (f) MRI compatible camera, and (g) Soft ware. The MRI compatibility of the system was successfully demonstrated in a clinical high-field MRI scanner. The ability of the robot to accurately move the transducer thus creating discrete and overlapping lesions in biological tissue was tested successfully. A simple, cost effective, portable positioning device has been developed which can be used in virtually any clinical MRI scanner since it can be sited on the scanner's table. The propagation of HIFU can use either a lateral or superior-inferior approach. Discrete and large lesions were created successfully with reproducible results. (orig.)

  3. Dynamic T2-mapping during magnetic resonance guided high intensity focused ultrasound ablation of bone marrow

    International Nuclear Information System (INIS)

    Waspe, Adam C.; Looi, Thomas; Mougenot, Charles; Amaral, Joao; Temple, Michael; Sivaloganathan, Siv; Drake, James M.

    2012-01-01

    Focal bone tumor treatments include amputation, limb-sparing surgical excision with bone reconstruction, and high-dose external-beam radiation therapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is an effective non-invasive thermotherapy for palliative management of bone metastases pain. MR thermometry (MRT) measures the proton resonance frequency shift (PRFS) of water molecules and produces accurate ( 2 , since T 2 increases linearly in fat during heating. T 2 -mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T 2 . Calibration of T 2 -based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T 2 and temperature with a thermocouple. A positive T 2 temperature dependence in bone marrow of 20 ms/°C was observed. Dynamic T 2 -mapping should enable accurate temperature monitoring during MR-HIFU treatment of bone marrow and shows promise for improving the safety and reducing the invasiveness of pediatric bone tumor treatments.

  4. Focused ultrasound in ophthalmology

    Directory of Open Access Journals (Sweden)

    Silverman RH

    2016-09-01

    Full Text Available Ronald H Silverman1,2 1Department of Ophthalmology, Columbia University Medical Center, 2F.L. Lizzi Center for Biomedical Engineering, Riverside Research, New York, NY, USA Abstract: The use of focused ultrasound to obtain diagnostically significant information about the eye goes back to the 1950s. This review describes the historical and technological development of ophthalmic ultrasound and its clinical application and impact. Ultrasound, like light, can be focused, which is crucial for formation of high-resolution, diagnostically useful images. Focused, single-element, mechanically scanned transducers are most common in ophthalmology. Specially designed transducers have been used to generate focused, high-intensity ultrasound that through thermal effects has been used to treat glaucoma (via cilio-destruction, tumors, and other pathologies. Linear and annular transducer arrays offer synthetic focusing in which precise timing of the excitation of independently addressable array elements allows formation of a converging wavefront to create a focus at one or more programmable depths. Most recently, linear array-based plane-wave ultrasound, in which the array emits an unfocused wavefront and focusing is performed solely on received data, has been demonstrated for imaging ocular anatomy and blood flow. While the history of ophthalmic ultrasound extends back over half-a-century, new and powerful technologic advances continue to be made, offering the prospect of novel diagnostic capabilities. Keywords: ophthalmic ultrasound, ultrasound biomicroscopy (UBM, high-intensity focused ultrasound (HIFU, ultrafast imaging, Doppler imaging 

  5. Efficacy of Magnetic Resonance-guided Focused Ultrasound Surgery for Bone Metastases Pain Palliation

    Science.gov (United States)

    Kawasaki, Motohiro; Nanba, Hirofumi; Kato, Tomonari; Tani, Toshikazu; Ushida, Takahiro

    2011-09-01

    Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is a novel treatment method that achieves non-invasive thermal ablation by focusing many ultrasound waves on a target tissue with real-time monitoring of the location and temperature of the target during the procedure. We investigated the palliative effect on pain and safety of MRgFUS in painful bone metastases. Six patients (mean age, 65.8 years) who met eligibility criteria for the clinical study approved by our Institutional Ethics Committee based on the cooperative protocol were treated with MRgFUS. Targeted sites included the sacrum (n = 1), ilium (n = 2), scapula (n = 2), and femur (n = 1). The mean follow-up period was 9.2 months. All procedures were performed as a single-session treatment using the treatment system that is integrated into the patient table of a magnetic resonance image (MRI) scanner. Endpoints were change in the intensity of pain due to bone metastases from before to after the treatment, as measured on a numerical rating scale, pain interference with daily activities as determined by the Brief pain inventory (BPI), change in images, and safety. Pain relief was obtained in all patients early after treatment, with a reduction in the mean pain score from 6.0±1.3 at baseline to 1.2±1.0 at the end of follow-up as well as in pain interference with daily activities. The mean time required for a single-session treatment was 83.7±37.0 min, with a mean number of sonications required of 13.3±3.7 and mean energy applied of 846.4±273.5 J. No significant growth of tumors was observed, nor were there treatment-related adverse events. These results suggest that MRgFUS has a non-invasive palliative effect on the localized pain in patients with bone metastasis. MRgFUS could become an option in treatment strategies for painful bone metastases in the future.

  6. Treatment of uterine leiomyoma with magnetic resonance-guided focused ultrasound surgery (MRgFUS)

    International Nuclear Information System (INIS)

    Fukunishi, Hidenobu

    2007-01-01

    Uterine leiomyoma is the most common pelvic tumor in women. Although hysterectomy has long been the standard treatment for uterine myoma, some uterus-preserving alternatives are available today. Among these, magnetic resonance-guided focused ultrasound surgery (MRgFUS) is a minimally-invasive procedure that uses high intensity ultrasound waves to ablate tissue. The present study investigates the efficacy of MRgFUS in the treatment of uterine myoma and the histopathological features on extirpated myoma tissue, when alternative surgical treatment is requisite. The Ethics Committee of Shinsuma Hospital approved the treatment of uterine myoma by MRgFUS, and written informed consent was obtained from all of the patients in compliance with the principles of good clinical practice. Between June 2004 and March 2007, 81 premenopausal patients with 125 myomas confirmed by T2-weighted MRI were treated by MRgFUS. The myomas were classified into 3 types based on signal intensity of T2-weighted images type I, low intensity; type II, intermediate intensity and type III, high intensity. The ablation (the non-perfused ratio of gadolinium injection) was about 55% in type I and type II, and 38% in type III. There was no correlation between the ablation ratio and the location or the size of the myoma. The uterine muscle was spared ablation when 2 combined myomas were treated as one tumor, suggesting that the vascularity was richer in the uterine muscle layer than in the myoma Sufficient ablation of the myoma near the Os sacrum is not able to attain immediately after the treatment; however, in several cases a complete non-perfusion margin was observed 3 or 6 months after the treatment. These cases yield very satisfactory results and it is meaningful to search for the reason why such good results were induced. Alternative treatment such as hysterectomy, myomectomy, trans cervical resection (TCR) or uterine artery embolization (UAE) was indicated for 13.6% of the patients. Here, we

  7. Magnetic resonance imaging-guided focused ultrasound ablation of uterine fibroids. Early clinical experience

    International Nuclear Information System (INIS)

    Mikami, Koji; Osuga, Keigo; Tomoda, Kaname; Nakamura, Hironobu; Murakami, Takamichi; Okada, Atsuya

    2008-01-01

    The aim of this study was to assess the feasibility and effectiveness of magnetic resonance (MRI)-guided focused ultrasound (MRIgFUS) ablation for uterine fibroids and to identify the candidates for this treatment. A total of 48 patients with a symptomatic uterine fibroid underwent MRIgFUS. The percent ablation volume was calculated, and the patients' characteristics and the MR imaging features of the fibroids that might predict the effect of this treatment were assessed. Changes in the symptoms related to the uterine fibroid were assessed at 6 and 12 months. The planned target zone were successfully treated in 32 patients with bulk-related and menstrual symptoms but unsuccessfully treated in the remaining 16 patients. These 16 patients were obese or their uterine fibroid showed heterogeneous high signal intensity on T2-weighted images. The 32 successfully treated patients were followed up for 6 months. At the 6-month follow-up, bulk-related and menstrual symptoms were diminished in 60% and 51% of patients, respectively. Among them, 17 patients were followed up for 12 months, and 9 of them who showed alleviation of bulk-related symptoms at 6 months had further improvement. The mean percent ablation volume of those nine patients was 51%. In 5 (33%) of the 15 patients with alleviation of menstrual symptoms at 6 months, the symptoms became worse at 12 months. There was a significant difference in the mean percent ablation volume between patients with alleviation of menstrual symptoms and those without (54% vs. 37%; P=0.03). MRIgFUS ablation is a safe, effective treatment for nonobese patients with symptomatic fibroids that show low signal intensity on T2-weighted images. Ablation of more than 50% of the fibroid volume may be needed with a short-term follow-up. (author)

  8. Workflow and intervention times of MR-guided focused ultrasound - Predicting the impact of new techniques.

    Science.gov (United States)

    Loeve, Arjo J; Al-Issawi, Jumana; Fernandez-Gutiérrez, Fabiola; Langø, Thomas; Strehlow, Jan; Haase, Sabrina; Matzko, Matthias; Napoli, Alessandro; Melzer, Andreas; Dankelman, Jenny

    2016-04-01

    Magnetic resonance guided focused ultrasound surgery (MRgFUS) has become an attractive, non-invasive treatment for benign and malignant tumours, and offers specific benefits for poorly accessible locations in the liver. However, the presence of the ribcage and the occurrence of liver motion due to respiration limit the applicability MRgFUS. Several techniques are being developed to address these issues or to decrease treatment times in other ways. However, the potential benefit of such improvements has not been quantified. In this research, the detailed workflow of current MRgFUS procedures was determined qualitatively and quantitatively by using observation studies on uterine MRgFUS interventions, and the bottlenecks in MRgFUS were identified. A validated simulation model based on discrete events simulation was developed to quantitatively predict the effect of new technological developments on the intervention duration of MRgFUS on the liver. During the observation studies, the duration and occurrence frequencies of all actions and decisions in the MRgFUS workflow were registered, as were the occurrence frequencies of motion detections and intervention halts. The observation results show that current MRgFUS uterine interventions take on average 213min. Organ motion was detected on average 2.9 times per intervention, of which on average 1.0 actually caused a need for rework. Nevertheless, these motion occurrences and the actions required to continue after their detection consumed on average 11% and up to 29% of the total intervention duration. The simulation results suggest that, depending on the motion occurrence frequency, the addition of new technology to automate currently manual MRgFUS tasks and motion compensation could potentially reduce the intervention durations by 98.4% (from 256h 5min to 4h 4min) in the case of 90% motion occurrence, and with 24% (from 5h 19min to 4h 2min) in the case of no motion. In conclusion, new tools were developed to predict how

  9. Sampling strategies for subsampled segmented EPI PRF thermometry in MR guided high intensity focused ultrasound

    Science.gov (United States)

    Odéen, Henrik; Todd, Nick; Diakite, Mahamadou; Minalga, Emilee; Payne, Allison; Parker, Dennis L.

    2014-01-01

    Purpose: To investigate k-space subsampling strategies to achieve fast, large field-of-view (FOV) temperature monitoring using segmented echo planar imaging (EPI) proton resonance frequency shift thermometry for MR guided high intensity focused ultrasound (MRgHIFU) applications. Methods: Five different k-space sampling approaches were investigated, varying sample spacing (equally vs nonequally spaced within the echo train), sampling density (variable sampling density in zero, one, and two dimensions), and utilizing sequential or centric sampling. Three of the schemes utilized sequential sampling with the sampling density varied in zero, one, and two dimensions, to investigate sampling the k-space center more frequently. Two of the schemes utilized centric sampling to acquire the k-space center with a longer echo time for improved phase measurements, and vary the sampling density in zero and two dimensions, respectively. Phantom experiments and a theoretical point spread function analysis were performed to investigate their performance. Variable density sampling in zero and two dimensions was also implemented in a non-EPI GRE pulse sequence for comparison. All subsampled data were reconstructed with a previously described temporally constrained reconstruction (TCR) algorithm. Results: The accuracy of each sampling strategy in measuring the temperature rise in the HIFU focal spot was measured in terms of the root-mean-square-error (RMSE) compared to fully sampled “truth.” For the schemes utilizing sequential sampling, the accuracy was found to improve with the dimensionality of the variable density sampling, giving values of 0.65 °C, 0.49 °C, and 0.35 °C for density variation in zero, one, and two dimensions, respectively. The schemes utilizing centric sampling were found to underestimate the temperature rise, with RMSE values of 1.05 °C and 1.31 °C, for variable density sampling in zero and two dimensions, respectively. Similar subsampling schemes

  10. A simulation model for predicting the temperature during the application of MR-guided focused ultrasound for stroke treatment using pulsed ultrasound

    Science.gov (United States)

    Hadjisavvas, V.; Damianou, C.

    2011-09-01

    In this paper a simulation model for predicting the temperature during the application of MR-guided focused ultrasound for stroke treatment using pulsed ultrasound is presented. A single element spherically focused transducer of 5 cm diameter, focusing at 10 cm and operating at either 0.5 MHz or 1 MHz was considered. The power field was estimated using the KZK model. The temperature was estimated using the bioheat equation. The goal was to extract the acoustic parameters (power, pulse duration, duty factor and pulse repetition frequency) that maintain a temperature increase of less than 1 °C during the application of a pulse ultrasound protocol. It was found that the temperature change increases linearly with duty factor. The higher the power, the lower the duty factor needed to keep the temperature change to the safe limit of 1 °C. The higher the frequency the lower the duty factor needed to keep the temperature change to the safe limit of 1 °C. Finally, the deeper the target, the higher the duty factor needed to keep the temperature change to the safe limit of 1 °C. The simulation model was tested in brain tissue during the application of pulse ultrasound and the measured temperature was in close agreement with the simulated temperature. This simulation model is considered to be very useful tool for providing acoustic parameters (frequency, power, duty factor, pulse repetition frequency) during the application of pulsed ultrasound at various depths in tissue so that a safe temperature is maintained during the treatment. This model could be tested soon during stroke clinical trials.

  11. MR-Guided Pulsed High-Intensity Focused Ultrasound Enhancement of Gene Therapy Combined With Androgen Deprivation and Radiotherapy for Prostate Cancer Treatment

    Science.gov (United States)

    2009-09-01

    ultrasound . J. Acoust. Soc.Am. 72 1926-1932, (1982) (7) Neppiras E A. Acoustic cavitation . Physics reports 61(3): 159-251, (1980) (8) ter Haar G R, Daniels...Guided Pulsed High-Intensity Focused Ultrasound Enhancement of 5b. GRANT NUMBER W81XWH-08-1-0469 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...failing to This work is aimed to study MR guided high intensity focused ultrasound (MRgHIFU) enhancement of gene therapy for Prostate Cancer. The

  12. MR-Guided High-Intensity Focused Ultrasound Ablation of Breast Cancer with a Dedicated Breast Platform

    International Nuclear Information System (INIS)

    Merckel, Laura G.; Bartels, Lambertus W.; Köhler, Max O.; Bongard, H. J. G. Desirée van den; Deckers, Roel; Mali, Willem P. Th. M.; Binkert, Christoph A.; Moonen, Chrit T.; Gilhuijs, Kenneth G. A.; Bosch, Maurice A. A. J. van den

    2013-01-01

    Optimizing the treatment of breast cancer remains a major topic of interest. In current clinical practice, breast-conserving therapy is the standard of care for patients with localized breast cancer. Technological developments have fueled interest in less invasive breast cancer treatment. Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is a completely noninvasive ablation technique. Focused beams of ultrasound are used for ablation of the target lesion without disrupting the skin and subcutaneous tissues in the beam path. MRI is an excellent imaging method for tumor targeting, treatment monitoring, and evaluation of treatment results. The combination of HIFU and MR imaging offers an opportunity for image-guided ablation of breast cancer. Previous studies of MR-HIFU in breast cancer patients reported a limited efficacy, which hampered the clinical translation of this technique. These prior studies were performed without an MR-HIFU system specifically developed for breast cancer treatment. In this article, a novel and dedicated MR-HIFU breast platform is presented. This system has been designed for safe and effective MR-HIFU ablation of breast cancer. Furthermore, both clinical and technical challenges are discussed, which have to be solved before MR-HIFU ablation of breast cancer can be implemented in routine clinical practice.

  13. Image-guided Navigation of Single-element Focused Ultrasound Transducer

    Science.gov (United States)

    Kim, Hyungmin; Chiu, Alan; Park, Shinsuk; Yoo, Seung-Schik

    2014-01-01

    The spatial specificity and controllability of focused ultrasound (FUS), in addition to its ability to modify the excitability of neural tissue, allows for the selective and reversible neuromodulation of the brain function, with great potential in neurotherapeutics. Intra-operative magnetic resonance imaging (MRI) guidance (in short, MRg) has limitations due to its complicated examination logistics, such as fixation through skull screws to mount the stereotactic frame, simultaneous sonication in the MRI environment, and restrictions in choosing MR-compatible materials. In order to overcome these limitations, an image-guidance system based on optical tracking and pre-operative imaging data is developed, separating the imaging acquisition for guidance and sonication procedure for treatment. Techniques to define the local coordinates of the focal point of sonication are presented. First, mechanical calibration detects the concentric rotational motion of a rigid-body optical tracker, attached to a straight rod mimicking the sonication path, pivoted at the virtual FUS focus. The spatial error presented in the mechanical calibration was compensated further by MRI-based calibration, which estimates the spatial offset between the navigated focal point and the ground-truth location of the sonication focus obtained from a temperature-sensitive MR sequence. MRI-based calibration offered a significant decrease in spatial errors (1.9±0.8 mm; 57% reduction) compared to the mechanical calibration method alone (4.4±0.9 mm). Using the presented method, pulse-mode FUS was applied to the motor area of the rat brain, and successfully stimulated the motor cortex. The presented techniques can be readily adapted for the transcranial application of FUS to intact human brain. PMID:25232203

  14. Reflection-artifact-free photoacoustic imaging using PAFUSion (photoacoustic-guided focused ultrasound)

    Science.gov (United States)

    Kuniyil Ajith Singh, Mithun; Jaeger, Michael; Frenz, Martin; Steenbergen, Wiendelt

    2016-03-01

    Reflection artifacts caused by acoustic inhomogeneities are a main challenge to deep-tissue photoacoustic imaging. Photoacoustic transients generated by the skin surface and superficial vasculature will propagate into the tissue and reflect back from echogenic structures to generate reflection artifacts. These artifacts can cause problems in image interpretation and limit imaging depth. In its basic version, PAFUSion mimics the inward travelling wave-field from blood vessel-like PA sources by applying focused ultrasound pulses, and thus provides a way to identify reflection artifacts. In this work, we demonstrate reflection artifact correction in addition to identification, towards obtaining an artifact-free photoacoustic image. In view of clinical applications, we implemented an improved version of PAFUSion in which photoacoustic data is backpropagated to imitate the inward travelling wave-field and thus the reflection artifacts of a more arbitrary distribution of PA sources that also includes the skin melanin layer. The backpropagation is performed in a synthetic way based on the pulse-echo acquisitions after transmission on each single element of the transducer array. We present a phantom experiment and initial in vivo measurements on human volunteers where we demonstrate significant reflection artifact reduction using our technique. The results provide a direct confirmation that reflection artifacts are prominent in clinical epi-photoacoustic imaging, and that PAFUSion can reduce these artifacts significantly to improve the deep-tissue photoacoustic imaging.

  15. MR-guided pulsed high intensity focused ultrasound enhancement of docetaxel combined with radiotherapy for prostate cancer treatment

    International Nuclear Information System (INIS)

    Mu Zhaomei; Ma, C-M; Chen Xiaoming; Cvetkovic, Dusica; Chen Lili; Pollack, Alan

    2012-01-01

    The purpose of this study is to evaluate the efficacy of the enhancement of docetaxel by pulsed focused ultrasound (pFUS) in combination with radiotherapy (RT) for treatment of prostate cancer in vivo. LNCaP cells were grown in the prostates of male nude mice. When the tumors reached a designated volume by MRI, tumor bearing mice were randomly divided into seven groups (n = 5): (1) pFUS alone; (2) RT alone; (3) docetaxel alone; (4) docetaxel + pFUS; (5) docetaxel + RT; (6) docetaxel + pFUS + RT, and (7) control. MR-guided pFUS treatment was performed using a focused ultrasound treatment system (InSightec ExAblate 2000) with a 1.5T GE MR scanner. Animals were treated once with pFUS, docetaxel, RT or their combinations. Docetaxel was given by i.v. injection at 5 mg kg −1 before pFUS. RT was given 2 Gy after pFUS. Animals were euthanized 4 weeks after treatment. Tumor volumes were measured on MRI at 1 and 4 weeks post-treatment. Results showed that triple combination therapies of docetaxel, pFUS and RT provided the most significant tumor growth inhibition among all groups, which may have potential for the treatment of prostate cancer due to an improved therapeutic ratio. (paper)

  16. MR-guided pulsed high intensity focused ultrasound enhancement of docetaxel combined with radiotherapy for prostate cancer treatment

    Science.gov (United States)

    Mu, Zhaomei; Ma, C.-M.; Chen, Xiaoming; Cvetkovic, Dusica; Pollack, Alan; Chen, Lili

    2012-01-01

    The purpose of this study is to evaluate the efficacy of the enhancement of docetaxel by pulsed focused ultrasound (pFUS) in combination with radiotherapy (RT) for treatment of prostate cancer in vivo. LNCaP cells were grown in the prostates of male nude mice. When the tumors reached a designated volume by MRI, tumor bearing mice were randomly divided into seven groups (n = 5): (1) pFUS alone; (2) RT alone; (3) docetaxel alone; (4) docetaxel + pFUS (5) docetaxel + RT (6) docetaxel + pFUS + RT, and (7) control. MR-guided pFUS treatment was performed using a focused ultrasound treatment system (InSightec ExAblate 2000) with a 1.5T GE MR scanner. Animals were treated once with pFUS, docetaxel, RT or their combinations. Docetaxel was given by i.v. injection at 5 mg kg-1 before pFUS. RT was given 2 Gy after pFUS. Animals were euthanized 4 weeks after treatment. Tumor volumes were measured on MRI at 1 and 4 weeks post-treatment. Results showed that triple combination therapies of docetaxel, pFUS and RT provided the most significant tumor growth inhibition among all groups, which may have potential for the treatment of prostate cancer due to an improved therapeutic ratio.

  17. Successful Magnetic Resonance Imaging-Guided Focused Ultrasound Surgery for Recurrent Uterine Fibroid Previously Treated with Uterine Artery Embolization

    Directory of Open Access Journals (Sweden)

    Sang-Wook Yoon

    2010-01-01

    Full Text Available A 45-year-old premenopausal woman was referred to our clinic due to recurring symptoms of uterine fibroids, nine years after a uterine artery embolization (UAE. At the time of screening, the patient presented with bilateral impairment and narrowing of the uterine arteries, which increased the risk of arterial perforation during repeated UAE procedures. The patient was subsequently referred for magnetic resonance imaging-guided focused ultrasound surgery (MRgFUS treatment. Following the treatment, the patient experienced a significant improvement in symptoms (symptom severity score was reduced from 47 to 12 by 1 year post-treatment. MR images at 3 months showed a 49% decrease in fibroid volume. There were no adverse events during the treatment or the follow-up period. This case suggests that MRgFUS can be an effective treatment option for patients with recurrent fibroids following previous UAE treatment.

  18. Osteoid osteoma: Magnetic resonance guided high intensity focused ultrasound for entirely non-invasive treatment. A prospective developmental study

    Science.gov (United States)

    Napoli, A.; de Soccio, V.; Cartocci, G.; Boni, F.; Anzidei, M.; Catalano, C.

    2017-03-01

    To determine the effect of acoustic energy delivered during MR guided Focused Ultrasound (MRgFUS) treatment of symptomatic osteoid osteomas. This prospective, IRB approved study involved 15 consecutive patients (11 m; 4f; mean age, 21) with clinical and imaging diagnosis of Osteoid Osteoma; all patients underwent MRgFUS ablation (ExAblate, InSightec; Discovery 750 MR unit, GE). Lesions located in the vertebral body were excluded, while lesions in proximity to joints or neurovascular bundles were included. Treatment success was determined at clinical and imaging follow-up at 1, 6 and 12 months post-treatment. A visual Analog Pain Score (VAS) was used to assess changes in symptoms. Bone changes at nidus site were evaluated on the basis of CT and dynamic ce-MR imaging (Gd-Bopta; Bracco) pre- and post-treatment. Treatment was carried out using a variable number of sonications (mean 4±1.8) with a mean energy deposition of 866±211 J. There were no treatment- or anesthesia-related complications. A statistically significant (p=0.001) difference was noted between the overall pre- and post-treatment mean VAS scores (8.3±1.6 and 0.6±1.5, respectively). Two treatments were conducted in patients with prior CTgRFA failure and needed two different session for achieving complete clinical successful. At imaging, edema and hyperemia associated with typical osteoid osteoma, gradually disappeared in all lesions. No apparent relationship between nidus vascular extinction and successful outcome was found. Variable reabsorption degree of sclerotic reaction was observed with nidus disappearance in 4 cases (27%). Treatment of osteoid osteoma using MR guided Focused Ultrasound can be performed safely with a high rate of success and without treatment related morbidity; our results indicated also a positive trend to bone rearrangement after treatment.

  19. MR-guided high intensity focused ultrasound thermoablation under temperature mapping monitoring for the treatment of uterine fibroids

    International Nuclear Information System (INIS)

    Xu Yonghua; Fu Zhongxiang; Yang Lixia; Chen Wenzhi; Liu Yingjiang; Ye Fangwei; Wang Zhibiao

    2010-01-01

    Objective: To assess the feasibility and effectiveness of MR-guided high intensity focused ultrasound (MRgHIFU) thermoablation under temperature mapping monitoring for the treatment of uterine fibroids. Methods: MRgHIFU was carried out in 52 patients with a total of 61 uterine fibroids. The mean age was (39.6 ± 7.3) years (ranged between 23-56 years), and the average diameter of the fibroids was(6.1 ± 2.1) cm (ranged between 1.2-10.7 cm). This procedure was accomplished by a JM-HIFU system (Mode JM15100, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Avanto TIM, Siemens, Germany), which provided real-time guidance and temperature mapping. Contrast-enhanced MR imaging was performed both immediately and three months after MRgHIFU treatment in order to evaluate the efficacy of thermal ablation. The treatment time and adverse events were recorded. The percentage of ablation volume was calculated after the procedure. The changes in the size of the uterine fibroid and in the clinical symptoms three months after the procedure were evaluated. Results: The mean fibroid volume for each case before and three months after MRgHIFU treatment was (113.3 ± 87.7) cm 3 and (58.1 ± 45.0) cm 3 respectively(P 3 (ranged between 7.7-282.9 cm 3 ) of fibroid volume was (19.8 ± 8.8) minutes. The mean energy of focused ultrasound delivered into the ablated fibroid tissue was (7.1 ± 6.7) J/mm 3 (ranged between 0.9-32.1 J/mm 3 ). The symptoms were relieved, the mean overall points decreased from (24.7 ± 4.8) to (16.7 ± 3.2) after therapy (P < 0.05). One patient experienced mild skin burn (small blisters), which subsided within two days. No other adverse events and complications were observed. Two patients got pregnant at three months after the treatment. Conclusion: MR-guided high intensity focused ultrasound treatment is a safe, effective and non-invasive technique for ablating uterine fibroids. A single thermoablation procedure is enough to

  20. Quality of MR thermometry during palliative MR-guided high-intensity focused ultrasound (MR-HIFU) treatment of bone metastases

    NARCIS (Netherlands)

    Lam, Mie K; Huisman, Merel; Nijenhuis, Robbert J; van den Bosch, Maurice; Viergever, Max A; Moonen, Chrit Tw; Bartels, LW

    2015-01-01

    BACKGROUND: Magnetic resonance (MR)-guided high-intensity focused ultrasound has emerged as a clinical option for palliative treatment of painful bone metastases, with MR thermometry (MRT) used for treatment monitoring. In this study, the general image quality of the MRT was assessed in terms of

  1. Volumetric MR-Guided High-Intensity Focused Ultrasound with Direct Skin Cooling for the Treatment of Symptomatic Uterine Fibroids : Proof-of-Concept Study

    NARCIS (Netherlands)

    Ikink, Marlijne E; van Breugel, Johanna M M; Schubert, Gerald; Nijenhuis, Robbert J; Bartels, LW; Moonen, Chrit T W; van den Bosch, Maurice A A J

    2015-01-01

    Objective. To prospectively assess the safety and technical feasibility of volumetric magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation with direct skin cooling (DISC) during treatment of uterine fibroids. Methods. In this proof-of-concept study, eight patients were

  2. [Ultrasound guided percutaneous nephrolithotripsy].

    Science.gov (United States)

    Guliev, B G

    2014-01-01

    The study was aimed to the evaluation of the effectiveness and results of ultrasound guided percutaneous nephrolithotripsy (PNL) for the treatment of patients with large stones in renal pelvis. The results of PNL in 138 patients who underwent surgery for kidney stones from 2011 to 2013 were analyzed. Seventy patients (Group 1) underwent surgery with combined ultrasound and radiological guidance, and 68 patients (Group 2)--only with ultrasound guidance. The study included patients with large renal pelvic stones larger than 2.2 cm, requiring the formation of a single laparoscopic approach. Using the comparative analysis, the timing of surgery, the number of intra- and postoperative complications, blood loss and length of stay were evaluated. Percutaneous access was successfully performed in all patients. Postoperative complications (exacerbation of chronic pyelonephritis, gross hematuria) were observed in 14.3% of patients in Group 1 and in 14.7% of patients in Group 2. Bleeding requiring blood transfusion, and injuries of adjacent organs were not registered. Efficacy of PNL in the Group 1 was 95.7%; 3 (4.3%) patients required additional interventions. In Group 2, the effectiveness of PNL was 94.1%, 4 (5.9%) patients additionally underwent extracorporeal lithotripsy. There were no significant differences in the effectiveness of PNL, the volume of blood loss and duration of hospitalization. Ultrasound guided PNL can be performed in large pelvic stones and sufficient expansion of renal cavities, thus reducing radiation exposure of patients and medical staff.

  3. First clinical experience with a dedicated MRI-guided high-intensity focused ultrasound system for breast cancer ablation

    Energy Technology Data Exchange (ETDEWEB)

    Merckel, Laura G.; Knuttel, Floor M.; Peters, Nicky H.G.M.; Mali, Willem P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, HP E 01.132, Utrecht (Netherlands); Deckers, Roel; Moonen, Chrit T.W.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Dalen, Thijs van [Diakonessenhuis Utrecht, Department of Surgery, Utrecht (Netherlands); Schubert, Gerald [Philips Healthcare, Best (Netherlands); Weits, Teun [Diakonessenhuis Utrecht, Department of Radiology, Utrecht (Netherlands); Diest, Paul J. van [University Medical Center Utrecht, Department of Pathology, Utrecht (Netherlands); Vaessen, Paul H.H.B. [University Medical Center Utrecht, Department of Anesthesiology, Utrecht (Netherlands); Gorp, Joost M.H.H. van [Diakonessenhuis Utrecht, Department of Pathology, Utrecht (Netherlands)

    2016-11-15

    To assess the safety and feasibility of MRI-guided high-intensity focused ultrasound (MR-HIFU) ablation in breast cancer patients using a dedicated breast platform. Patients with early-stage invasive breast cancer underwent partial tumour ablation prior to surgical resection. MR-HIFU ablation was performed using proton resonance frequency shift MR thermometry and an MR-HIFU system specifically designed for breast tumour ablation. The presence and extent of tumour necrosis was assessed by histopathological analysis of the surgical specimen. Pearson correlation coefficients were calculated to assess the relationship between sonication parameters, temperature increase and size of tumour necrosis at histopathology. Ten female patients underwent MR-HIFU treatment. No skin redness or burns were observed in any of the patients. No correlation was found between the applied energy and the temperature increase. In six patients, tumour necrosis was observed with a maximum diameter of 3-11 mm. In these patients, the number of targeted locations was equal to the number of areas with tumour necrosis. A good correlation was found between the applied energy and the size of tumour necrosis at histopathology (Pearson = 0.76, p = 0.002). Our results show that MR-HIFU ablation with the dedicated breast system is safe and results in histopathologically proven tumour necrosis. (orig.)

  4. [Neuroprotective subthalamotomy in Parkinson's disease. The role of magnetic resonance-guided focused ultrasound in early surgery].

    Science.gov (United States)

    Guridi, Jorge; Marigil, Miguel; Becerra, Victoria; Parras, Olga

    Subthalamic nucleus hyperactivity in Parkinson's disease may be a very early phenomenon. Its start is not well known, and it may occur during the pre-symptomatic disease stage. Glutamatergic hyperactivity may be neurotoxic over the substantia nigra compacta dopaminergic neurons. If this occurred, the excitatory neurotransmitter, glutamate, should affect the neurons that maintain a high turnover as a compensatory mechanism. Would a subthalamic nucleus lesion decrease this hyperactivity and thus be considered as a neuroprotective mechanism for dopaminergic neurons? The authors hypothesise about the possibility to perform surgery on a subthalamic nucleus lesion at a very early stage in order to avoid the neurotoxic glutamatergic effect over the dopaminergic neurons, and therefore be considered as a neuroprotective surgery able to alter the progress of the disease during early motor symptoms. In this regard, magnetic resonance-guided focused ultrasound techniques open a new window in the stereotactic armamentarium. Copyright © 2016 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Factors associated with successful magnetic resonance-guided focused ultrasound treatment: efficiency of acoustic energy delivery through the skull.

    Science.gov (United States)

    Chang, Won Seok; Jung, Hyun Ho; Zadicario, Eyal; Rachmilevitch, Itay; Tlusty, Tal; Vitek, Shuki; Chang, Jin Woo

    2016-02-01

    Magnetic resonance-guided focused ultrasound surgery (MRgFUS) was recently introduced as treatment for movement disorders such as essential tremor and advanced Parkinson's disease (PD). Although deep brain target lesions are successfully generated in most patients, the target area temperature fails to increase in some cases. The skull is one of the greatest barriers to ultrasonic energy transmission. The authors analyzed the skull-related factors that may have prevented an increase in target area temperatures in patients who underwent MRgFUS. The authors retrospectively reviewed data from clinical trials that involved MRgFUS for essential tremor, idiopathic PD, and obsessive-compulsive disorder. Data from 25 patients were included. The relationships between the maximal temperature during treatment and other factors, including sex, age, skull area of the sonication field, number of elements used, skull volume of the sonication field, and skull density ratio (SDR), were determined. Among the various factors, skull volume and SDR exhibited relationships with the maximum temperature. Skull volume was negatively correlated with maximal temperature (p = 0.023, r(2) = 0.206, y = 64.156 - 0.028x, whereas SDR was positively correlated with maximal temperature (p = 0.009, r(2) = 0.263, y = 49.643 + 11.832x). The other factors correlate with the maximal temperature, although some factors showed a tendency to correlate. Some skull-related factors correlated with the maximal target area temperature. Although the number of patients in the present study was relatively small, the results offer information that could guide the selection of MRgFUS candidates.

  6. Efficacy and safety of ultrasound-guided high intensity focused ultrasound ablation of symptomatic uterine fibroids in Black women: a preliminary study.

    Science.gov (United States)

    Zhang, C; Jacobson, H; Ngobese, Z E; Setzen, R

    2017-08-01

    To evaluate the therapeutic effect and safety of ultrasound-guided high-intensity focused ultrasound (USgHIFU) treatment on symptomatic uterine fibroids in Black women. A feasibility study. Gynaecological department in a teaching hospital in South Africa. Premenopausal women with uterus fibroids. Twenty-six patients with 53 fibroids who underwent USgHIFU treatment were enrolled. The USgHIFU treatment information was recorded, including treatment time, sonication time and total energy. Adverse events were also observed and recorded during and after treatment. Safety and efficacy of USgHIFU for the treatment of uterine fibroids in Black women. The median volume of fibroids was 52.7 (interquartile range, 18.6-177.4) cm 3 . According to USgHIFU treatment plan, total energy of 298.6 ± 169.3 kJ (range, 76.0-889.2) within treatment time of 90.3 ± 43.3 minutes (range, 14.0-208.0), in which sonication time of 774.0 ± 432.9 seconds (range, 190.0-2224.0) was used to ablate fibroids. The average ablation rate was 80.6 ± 9.7% (range, 46.5-94.5%). During the procedure, 69.2% of the patients reported lower abdominal pain, 57.7% sciatic/buttock pain, 38.5% burning skin, and 34.6% transient leg pain. No severe complications were observed. USgHIFU is feasible and safe to use to treat symptomatic uterine fibroids in Black women. Multiple uterine fibroids are more frequently detected in Black women. USgHIFU is feasible and safe for the treatment of uterine fibroids in Black women. © 2017 Royal College of Obstetricians and Gynaecologists.

  7. HematoPorphyrin Monomethyl Ether polymer contrast agent for ultrasound/photoacoustic dual-modality imaging-guided synergistic high intensity focused ultrasound (HIFU) therapy.

    Science.gov (United States)

    Yan, Sijing; Lu, Min; Ding, Xiaoya; Chen, Fei; He, Xuemei; Xu, Chunyan; Zhou, Hang; Wang, Qi; Hao, Lan; Zou, Jianzhong

    2016-08-18

    This study is to prepare a hematoporphyrin monomethyl ether (HMME)-loaded poly(lactic-co-glycolic acid) (PLGA) microcapsules (HMME/PLGA), which could not only function as efficient contrast agent for ultrasound (US)/photoacoustic (PA) imaging, but also as a synergistic agent for high intensity focused ultrasound (HIFU) ablation. Sonosensitizer HMME nanoparticles were integrated into PLGA microcapsules with the double emulsion evaporation method. After characterization, the cell-killing and cell proliferation-inhibiting effects of HMME/PLGA microcapsules on ovarian cancer SKOV3 cells were assessed. The US/PA imaging-enhancing effects and synergistic effects on HIFU were evaluated both in vitro and in vivo. HMME/PLGA microcapsules were highly dispersed with well-defined spherical morphology (357 ± 0.72 nm in diameter, PDI = 0.932). Encapsulation efficiency and drug-loading efficiency were 58.33 ± 0.95% and 4.73 ± 0.15%, respectively. The HMME/PLGA microcapsules remarkably killed the SKOV3 cells and inhibited the cell proliferation, significantly enhanced the US/PA imaging results and greatly enhanced the HIFU ablation effects on ovarian cancer in nude mice by the HMME-mediated sono-dynamic chemistry therapy (SDT). HMME/PLGA microcapsules represent a potential multifunctional contrast agent for HIFU diagnosis and treatment, which might provide a novel strategy for the highly efficient imaging-guided non-invasive HIFU synergistic therapy for cancers by SDT in clinic.

  8. T1-weighted MRI as a substitute to CT for refocusing planning in MR-guided focused ultrasound

    International Nuclear Information System (INIS)

    Wintermark, Max; Sumer, Suna; Lau, Benison; Cupino, Alan; Tustison, Nicholas J; Demartini, Nicholas; Elias, William J; Kassell, Neal; Patrie, James T; Xin, Wenjun; Eames, Matt; Snell, John; Hananel, Arik; Aubry, Jean-Francois

    2014-01-01

    Precise focusing is essential for transcranial MRI-guided focused ultrasound (TcMRgFUS) to minimize collateral damage to non-diseased tissues and to achieve temperatures capable of inducing coagulative necrosis at acceptable power deposition levels. CT is usually used for this refocusing but requires a separate study (CT) ahead of the TcMRgFUS procedure. The goal of this study was to determine whether MRI using an appropriate sequence would be a viable alternative to CT for planning ultrasound refocusing in TcMRgFUS. We tested three MRI pulse sequences (3D T1 weighted 3D volume interpolated breath hold examination (VIBE), proton density weighted 3D sampling perfection with applications optimized contrasts using different flip angle evolution and 3D true fast imaging with steady state precision T2-weighted imaging) on patients who have already had a CT scan performed. We made detailed measurements of the calvarial structure based on the MRI data and compared those so-called ‘virtual CT’ to detailed measurements of the calvarial structure based on the CT data, used as a reference standard. We then loaded both standard and virtual CT in a TcMRgFUS device and compared the calculated phase correction values, as well as the temperature elevation in a phantom. A series of Bland–Altman measurement agreement analyses showed T1 3D VIBE as the optimal MRI sequence, with respect to minimizing the measurement discrepancy between the MRI derived total skull thickness measurement and the CT derived total skull thickness measurement (mean measurement discrepancy: 0.025; 95% CL (−0.22–0.27); p = 0.825). The T1-weighted sequence was also optimal in estimating skull CT density and skull layer thickness. The mean difference between the phase shifts calculated with the standard CT and the virtual CT reconstructed from the T1 dataset was 0.08 ± 1.2 rad on patients and 0.1 ± 0.9 rad on phantom. Compared to the real CT, the MR-based correction showed a 1 °C drop on the

  9. Methodology on quantification of sonication duration for safe application of MR guided focused ultrasound for liver tumour ablation.

    Science.gov (United States)

    Mihcin, Senay; Karakitsios, Ioannis; Le, Nhan; Strehlow, Jan; Demedts, Daniel; Schwenke, Michael; Haase, Sabrina; Preusser, Tobias; Melzer, Andreas

    2017-12-01

    Magnetic Resonance Guided Focused Ultrasound (MRgFUS) for liver tumour ablation is a challenging task due to motion caused by breathing and occlusion due the ribcage between the transducer and the tumour. To overcome these challenges, a novel system for liver tumour ablation during free breathing has been designed. The novel TRANS-FUSIMO Treatment System (TTS, EUFP7) interacts with a Magnetic Resonance (MR) scanner and a focused ultrasound transducer to sonicate to a moving target in liver. To meet the requirements of ISO 13485; a quality management system for medical device design, the system needs to be tested for certain process parameters. The duration of sonication and, the delay after the sonication button is activated, are among the parameters that need to be quantified for efficient and safe ablation of tumour tissue. A novel methodology is developed to quantify these process parameters. A computerised scope is programmed in LabVIEW to collect data via hydrophone; where the coordinates of fiber-optic sensor assembly was fed into the TRANS-FUSIMO treatment software via Magnetic Resonance Imaging (MRI) to sonicate to the tip of the sensor, which is synchronised with the clock of the scope, embedded in a degassed water tank via sensor assembly holder. The sonications were executed for 50 W, 100 W, 150 W for 10 s to quantify the actual sonication duration and the delay after the emergency stop by two independent operators for thirty times. The deviation of the system from the predefined specs was calculated. Student's-T test was used to investigate the user dependency. The duration of sonication and the delay after the sonication were quantified successfully with the developed method. TTS can sonicate with a maximum deviation of 0.16 s (Std 0.32) from the planned duration and with a delay of 14 ms (Std 0.14) for the emergency stop. Student's T tests indicate that the results do not depend on operators (p > .05). The evidence obtained via this

  10. Targeted Vessel Ablation for More Efficient Magnetic Resonance-Guided High-Intensity Focused Ultrasound Ablation of Uterine Fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Voogt, Marianne J., E-mail: m.voogt@umcutrecht.nl [University Medical Center Utrecht, Department of Radiology (Netherlands); Stralen, Marijn van [University Medical Center Utrecht, Image Sciences Institute (Netherlands); Ikink, Marlijne E. [University Medical Center Utrecht, Department of Radiology (Netherlands); Deckers, Roel; Vincken, Koen L.; Bartels, Lambertus W. [University Medical Center Utrecht, Image Sciences Institute (Netherlands); Mali, Willem P. Th. M.; Bosch, Maurice A. A. J. van den [University Medical Center Utrecht, Department of Radiology (Netherlands)

    2012-10-15

    Purpose: To report the first clinical experience with targeted vessel ablation during magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) treatment of symptomatic uterine fibroids. Methods: Pretreatment T1-weighted contrast-enhanced magnetic resonance angiography was used to create a detailed map of the uterine arteries and feeding branches to the fibroids. A three-dimensional overlay of the magnetic resonance angiography images was registered on 3D T2-weighted pretreatment imaging data. Treatment was focused primarily on locations where supplying vessels entered the fibroid. Patients were followed 6 months after treatment with a questionnaire to assess symptoms and quality of life (Uterine Fibroid Symptom and Quality of Life) and magnetic resonance imaging to quantify shrinkage of fibroid volumes. Results: In two patients, three fibroids were treated with targeted vessel ablation during MR-HIFU. The treatments resulted in almost total fibroid devascularization with nonperfused volume to total fibroid volume ratios of 84, 68, and 86%, respectively, of treated fibroids. The predicted ablated volumes during MR-HIFU in patients 1 and 2 were 45, 40, and 82 ml, respectively, while the nonperfused volumes determined immediately after treatment were 195, 92, and 190 ml respectively, which is 4.3 (patient 1) and 2.3 (patient 2) times higher than expected based on the thermal dose distribution. Fibroid-related symptoms reduced after treatment, and quality of life improved. Fibroid volume reduction ranged 31-59% at 6 months after treatment. Conclusion: Targeted vessel ablation during MR-HIFU allowed nearly complete fibroid ablation in both patients. This technique may enhance the use of MR-HIFU for fibroid treatment in clinical practice.

  11. Predicting variation in subject thermal response during transcranial magnetic resonance guided focused ultrasound surgery: Comparison in seventeen subject datasets

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, Urvi, E-mail: urvi.vyas@gmail.com; Ghanouni, Pejman; Halpern, Casey H.; Pauly, Kim Butts [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Elias, Jeff [Department of Neurological Surgery, University of Virginia, Charlottesville, Virginia 22908 (United States)

    2016-09-15

    Purpose: In transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) treatments, the acoustic and spatial heterogeneity of the skull cause reflection, absorption, and scattering of the acoustic beams. These effects depend on skull-specific parameters and can lead to patient-specific thermal responses to the same transducer power. In this work, the authors develop a simulation tool to help predict these different experimental responses using 3D heterogeneous tissue models based on the subject CT images. The authors then validate and compare the predicted skull efficiencies to an experimental metric based on the subject thermal responses during tcMRgFUS treatments in a dataset of seventeen human subjects. Methods: Seventeen human head CT scans were used to create tissue acoustic models, simulating the effects of reflection, absorption, and scattering of the acoustic beam as it propagates through a heterogeneous skull. The hybrid angular spectrum technique was used to model the acoustic beam propagation of the InSightec ExAblate 4000 head transducer for each subject, yielding maps of the specific absorption rate (SAR). The simulation assumed the transducer was geometrically focused to the thalamus of each subject, and the focal SAR at the target was used as a measure of the simulated skull efficiency. Experimental skull efficiency for each subject was calculated using the thermal temperature maps from the tcMRgFUS treatments. Axial temperature images (with no artifacts) were reconstructed with a single baseline, corrected using a referenceless algorithm. The experimental skull efficiency was calculated by dividing the reconstructed temperature rise 8.8 s after sonication by the applied acoustic power. Results: The simulated skull efficiency using individual-specific heterogeneous models predicts well (R{sup 2} = 0.84) the experimental energy efficiency. Conclusions: This paper presents a simulation model to predict the variation in thermal responses

  12. SU-E-J-04: Integration of Interstitial High Intensity Therapeutic Ultrasound Applicators On a Clinical MRI-Guided High Intensity Focused Ultrasound Treatment Planning Software Platform

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Partanen, A [Philips Healthcare, Andover, Massachusetts (United States); Ghoshal, G; Burdette, E [Acoustic MedSystems Inc., Savoy, IL (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: Interstitial high intensity therapeutic ultrasound (HITU) applicators can be used to ablate tissue percutaneously, allowing for minimally-invasive treatment without ionizing radiation [1,2]. The purpose of this study was to evaluate the feasibility and usability of combining multielement interstitial HITU applicators with a clinical magnetic resonance imaging (MRI)-guided focused ultrasound software platform. Methods: The Sonalleve software platform (Philips Healthcare, Vantaa, Finland) combines anatomical MRI for target selection and multi-planar MRI thermometry to provide real-time temperature information. The MRI-compatible interstitial US applicators (Acoustic MedSystems, Savoy, IL, USA) had 1–4 cylindrical US elements, each 1 cm long with either 180° or 360° of active surface. Each applicator (4 Fr diameter, enclosed within a 13 Fr flexible catheter) was inserted into a tissue-mimicking agar-silica phantom. Degassed water was circulated around the transducers for cooling and coupling. Based on the location of the applicator, a virtual transducer overlay was added to the software to assist targeting and to allow automatic thermometry slice placement. The phantom was sonicated at 7 MHz for 5 minutes with 6–8 W of acoustic power for each element. MR thermometry data were collected during and after sonication. Results: Preliminary testing indicated that the applicator location could be identified in the planning images and the transducer locations predicted within 1 mm accuracy using the overlay. Ablation zones (thermal dose ≥ 240 CEM43) for 2 active, adjacent US elements ranged from 18 mm × 24 mm (width × length) to 25 mm × 25 mm for the 6 W and 8 W sonications, respectively. Conclusion: The combination of interstitial HITU applicators and this software platform holds promise for novel approaches in minimally-invasive MRI-guided therapy, especially when bony structures or air-filled cavities may preclude extracorporeal HIFU.[1] Diederich et al

  13. SU-E-J-162: Quality Assurance Procedures for MR Guided Focused Ultrasound Treatment of Bone Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L; Chen, X; Wang, B; Gupta, R; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2014-06-01

    Purpose: The purpose of this work is to develop and verify our quality assurance (QA) procedures to ensure the safety and efficacy of MR-guided focused ultrasound (MRgFUS) treatment of bone metastases. Methods: A practical QA program was developed. Monthly and daily QA (DQA) procedures were performed. The major QA items included the checks of the machine hardware, software and patient safety features. Briefly, these checks/tests include: 1) the cooling system reservoir and treatment table; 2) power to the treatment table; 3) the MR coil; 4) the transducer position with MRI; 5) image display on the treatment work station; 6) the effective focal spot in 3 directions using MR thermometry; and 7) all the safety devices including a sonication lamp, and the emergency stop-sonication switches. In order to avoid patient skin burn, it is important to remove gas bubbles in the interfaces between the treatment table and the gel pad, and the gel pad and patients skin during the patient setup. Our QA procedures have been verified and evaluated through patient treatments. Seven patients with scapula, humeral head, sacrum, ilium, pubic ramus and acetabular bone metastases were treated using MRgFUS. Results: Our study showed that all seven patients tolerated the MRgFUS treatment well. No skin toxicity or other complications were observed. The pain score (0–10) using the visual analog scale (VAS) was significantly reduced from 8.0 ± 1.1 before treatment to 4.7 ± 3.0, 3.0 ± 1.5, 3.2 ± 2.8 and 3.4 ± 1.5 at one day, one month, two months and three months after the MRgFUS treatment, respectively. Conclusion: We demonstrated that with the appropriate QA procedures, MRgFUS is a safe, effective and noninvasive treatment modality for palliation of bone metastases.

  14. SU-E-J-162: Quality Assurance Procedures for MR Guided Focused Ultrasound Treatment of Bone Metastasis

    International Nuclear Information System (INIS)

    Chen, L; Chen, X; Wang, B; Gupta, R; Ma, C

    2014-01-01

    Purpose: The purpose of this work is to develop and verify our quality assurance (QA) procedures to ensure the safety and efficacy of MR-guided focused ultrasound (MRgFUS) treatment of bone metastases. Methods: A practical QA program was developed. Monthly and daily QA (DQA) procedures were performed. The major QA items included the checks of the machine hardware, software and patient safety features. Briefly, these checks/tests include: 1) the cooling system reservoir and treatment table; 2) power to the treatment table; 3) the MR coil; 4) the transducer position with MRI; 5) image display on the treatment work station; 6) the effective focal spot in 3 directions using MR thermometry; and 7) all the safety devices including a sonication lamp, and the emergency stop-sonication switches. In order to avoid patient skin burn, it is important to remove gas bubbles in the interfaces between the treatment table and the gel pad, and the gel pad and patients skin during the patient setup. Our QA procedures have been verified and evaluated through patient treatments. Seven patients with scapula, humeral head, sacrum, ilium, pubic ramus and acetabular bone metastases were treated using MRgFUS. Results: Our study showed that all seven patients tolerated the MRgFUS treatment well. No skin toxicity or other complications were observed. The pain score (0–10) using the visual analog scale (VAS) was significantly reduced from 8.0 ± 1.1 before treatment to 4.7 ± 3.0, 3.0 ± 1.5, 3.2 ± 2.8 and 3.4 ± 1.5 at one day, one month, two months and three months after the MRgFUS treatment, respectively. Conclusion: We demonstrated that with the appropriate QA procedures, MRgFUS is a safe, effective and noninvasive treatment modality for palliation of bone metastases

  15. SU-F-J-225: Histology Study of MR Guided Pulsed Focused Ultrasound On Treatment of Prostate Cancer in Vivo

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L; Cvetkovic, D; Chen, X; Wang, B; Gupta, R; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2016-06-15

    Purpose: Our previous study demonstrated significant tumor growth delay in the mice treated with pulsed high intensity focused ultrasound (pHIFU). The purpose of this study is to understand the cell killing mechanisms of pHIFU. Methods: Prostate cancer cells (LNCaP), were grown orthotopically in 17 nude mice. Tumor-bearing mice were treated using pHIFU with an acoustic power of 25W, pulse width 100msec and 300 pulses in one sonication under MR guidance. Mutiple sonications were used to cover the whole tumor volume. The temperature (less than 40 degree centigrade in the focal spot) was monitored using MR thermometry. Animals were euthanized at pre-determined time points (n=2) after treatment: 0 hours; 6 hrs; 24 hrs; 48 hrs; 4 days and 7 days. Two tumorbearing mice were used as control. Three tumor-bearing mice were treated with radiation (RT, 2 Gy) using 6 MV photon beams. RT treated mice were euthanized at 0 hr, 6 hrs and 24 hrs. The tumors were processed for immunohistochemical (IHC) staining for PARP (a surrogate of apoptosis). A multispectral imaging analysis system was used to quantify the expression of PARP staining. Cell apoptosis was calculated based on the PARP expression level using the DAB analysis software. Results: Our data showed that PARP related apoptosis peaked at 48 hrs and 7 days in pHIFU treated mice, which is comparable to that for the RT group at 24 hrs. The preliminary results from this study were consistent with our previous study on tumor growth delay using pHIFU. Conclusion: Our results demonstrated that non-thermal pHIFU increased apoptotic tumor cell death through the PARP related pathway. MR guided pHIFU may have a great potential as a safe, noninvasive treatment modality for cancer therapy. This treatment modality may synergize with PARP inhibitors to achieve better therapeutic result.

  16. Midterm Results after Uterine Artery Embolization Versus MR-Guided High-Intensity Focused Ultrasound Treatment for Symptomatic Uterine Fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Froeling, V., E-mail: vera.froeling@charite.de; Meckelburg, K., E-mail: katrin.meckelburg@charite.de; Scheurig-Muenkler, C., E-mail: christian.scheurig-muenkler@charite.de; Schreiter, N. F., E-mail: nils.schreiter@charite.de; Kamp, J., E-mail: julia.kamp@charite.de; Maurer, M. H., E-mail: martin.maurer@charite.de; Beck, A., E-mail: alexander.beck@charite.de; Hamm, B., E-mail: bernd.hamm@charite.de; Kroencke, T. J., E-mail: Thomas.kroencke@charite.de [Charite-Universitaetsmedizin Berlin, Department of Radiology (Germany)

    2013-12-15

    Purpose: To compare the rate of reintervention and midterm changes in symptom severity (SS) and Total health-related quality of life (HRQoL) scores after uterine artery embolization (UAE) and magnetic resonance-guided high-intensity focused ultrasound (MR-g HIFU) for symptomatic uterine fibroids. Methods: Eighty women (median age 38.3 years), equally eligible for MR-g HIFU and UAE who underwent one of both treatments between 2002 and 2009 at our institution, were included. The primary end point of the study was defined as the rate of reintervention after both therapies. The secondary outcome was defined as changes in SS and Total HRQoL scores after treatment. SS and Total HRQoL scores before treatment and at midterm follow-up (median 13.3 months) were assessed by the uterine fibroid symptom and quality-of-life questionnaire (UFS-QoL) and compared. Results: The rate of reintervention was significantly lower after UAE than after MR-g HIFU (p = 0.002). After both treatments, SS and Total HRQoL scores improved significantly from baseline to follow-up (UAE: p < 0.001, p < 0.001; MR-g HIFU: p = 0.002, p < 0.001). Total HRQoL scores were significantly higher after UAE than after MR-g HIFU (p = 0.032). Changes in the SS scores did not differ significantly for both treatments (p = 0.061). Conclusion: UAE and MR-g HIFU significantly improved the health-related quality of life of women with symptomatic uterine fibroids. After UAE, the change in Total HRQoL score improvement was significantly better, and a significantly lower rate of reintervention was observed.

  17. Midterm Results after Uterine Artery Embolization Versus MR-Guided High-Intensity Focused Ultrasound Treatment for Symptomatic Uterine Fibroids

    International Nuclear Information System (INIS)

    Froeling, V.; Meckelburg, K.; Scheurig-Muenkler, C.; Schreiter, N. F.; Kamp, J.; Maurer, M. H.; Beck, A.; Hamm, B.; Kroencke, T. J.

    2013-01-01

    Purpose: To compare the rate of reintervention and midterm changes in symptom severity (SS) and Total health-related quality of life (HRQoL) scores after uterine artery embolization (UAE) and magnetic resonance–guided high-intensity focused ultrasound (MR-g HIFU) for symptomatic uterine fibroids. Methods: Eighty women (median age 38.3 years), equally eligible for MR-g HIFU and UAE who underwent one of both treatments between 2002 and 2009 at our institution, were included. The primary end point of the study was defined as the rate of reintervention after both therapies. The secondary outcome was defined as changes in SS and Total HRQoL scores after treatment. SS and Total HRQoL scores before treatment and at midterm follow-up (median 13.3 months) were assessed by the uterine fibroid symptom and quality-of-life questionnaire (UFS-QoL) and compared. Results: The rate of reintervention was significantly lower after UAE than after MR-g HIFU (p = 0.002). After both treatments, SS and Total HRQoL scores improved significantly from baseline to follow-up (UAE: p < 0.001, p < 0.001; MR-g HIFU: p = 0.002, p < 0.001). Total HRQoL scores were significantly higher after UAE than after MR-g HIFU (p = 0.032). Changes in the SS scores did not differ significantly for both treatments (p = 0.061). Conclusion: UAE and MR-g HIFU significantly improved the health-related quality of life of women with symptomatic uterine fibroids. After UAE, the change in Total HRQoL score improvement was significantly better, and a significantly lower rate of reintervention was observed

  18. SU-E-T-245: MR Guided Focused Ultrasound Increased PARP Related Apoptosis On Prostate Cancer in Vivo

    International Nuclear Information System (INIS)

    Chen, L; Chen, X; Cvetkovic, D; Gupta, R; Yang, D; Ma, C

    2014-01-01

    Purpose: Our previous study demonstrated that significant tumor growth delay was observed in the mice treated with pulsed high intensity focused ultrasound (pHIFU). The purpose of this study is to understand the cell killing mechanisms of pHIFU. Methods: Prostate cancer cells (LNCaP), were grown orthotopically in 17 nude mice. Tumor-bearing mice were treated using pHIFU with an acoustic power of 25W, pulse width 100msec and 300 pulses in one sonication under MR guidance. Mutiple sonications were used to cover the whole tumor volume. Temperature (less than 40 degree centigrade in the focal spot) was monitored using MR thermometry. Animals were euthanized at pre-determined time points (n=2) after treatment: 0 hours; 6 hrs; 24 hrs; 48 hrs; 4 days and 7 days. Two tumorbearing mice were used as control. Three tumor-bearing mice were treated with radiation (RT, 2 Gy) using 6 MV photon beams. RT treated mice were euthanized at 0 hr, 6 hrs and 24 hrs. The tumors were processed for immunohistochemical (IHC) staining for PARP (a surrogate of apoptosis). A multispectral imaging analysis system was used to quantify the expression of PARP staining. Cell apoptosis was calculated based on the PARP expression level, which is the intensity of the DAB reaction. Results: Our data showed that PARP related apoptosis peaked at 48 hrs and 7 days in pHIFU treated mice, which is comparable to that for the RT group at 24 hrs. The preliminary results from this study were consistent with our previous study on tumor growth delay using pHIFU. Conclusion: Our results demonstrated that non-thermal pHIFU increased apoptotic tumor cell death through the PARP related pathway. MR guided pHIFU may have a great potential as a safe, noninvasive treatment modality for cancer therapy. This treatment modality might be able to synergize with PARP inhibitors to achieve better result

  19. SU-F-J-225: Histology Study of MR Guided Pulsed Focused Ultrasound On Treatment of Prostate Cancer in Vivo

    International Nuclear Information System (INIS)

    Chen, L; Cvetkovic, D; Chen, X; Wang, B; Gupta, R; Ma, C

    2016-01-01

    Purpose: Our previous study demonstrated significant tumor growth delay in the mice treated with pulsed high intensity focused ultrasound (pHIFU). The purpose of this study is to understand the cell killing mechanisms of pHIFU. Methods: Prostate cancer cells (LNCaP), were grown orthotopically in 17 nude mice. Tumor-bearing mice were treated using pHIFU with an acoustic power of 25W, pulse width 100msec and 300 pulses in one sonication under MR guidance. Mutiple sonications were used to cover the whole tumor volume. The temperature (less than 40 degree centigrade in the focal spot) was monitored using MR thermometry. Animals were euthanized at pre-determined time points (n=2) after treatment: 0 hours; 6 hrs; 24 hrs; 48 hrs; 4 days and 7 days. Two tumorbearing mice were used as control. Three tumor-bearing mice were treated with radiation (RT, 2 Gy) using 6 MV photon beams. RT treated mice were euthanized at 0 hr, 6 hrs and 24 hrs. The tumors were processed for immunohistochemical (IHC) staining for PARP (a surrogate of apoptosis). A multispectral imaging analysis system was used to quantify the expression of PARP staining. Cell apoptosis was calculated based on the PARP expression level using the DAB analysis software. Results: Our data showed that PARP related apoptosis peaked at 48 hrs and 7 days in pHIFU treated mice, which is comparable to that for the RT group at 24 hrs. The preliminary results from this study were consistent with our previous study on tumor growth delay using pHIFU. Conclusion: Our results demonstrated that non-thermal pHIFU increased apoptotic tumor cell death through the PARP related pathway. MR guided pHIFU may have a great potential as a safe, noninvasive treatment modality for cancer therapy. This treatment modality may synergize with PARP inhibitors to achieve better therapeutic result.

  20. Dynamic T{sub 2}-mapping during magnetic resonance guided high intensity focused ultrasound ablation of bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Waspe, Adam C.; Looi, Thomas; Mougenot, Charles; Amaral, Joao; Temple, Michael; Sivaloganathan, Siv; Drake, James M. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Philips Healthcare Canada, Markham, ON, L6C 2S3 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada); Department of Applied Mathematics, University of Waterloo, Waterloo, ON, N2L 3G1 (Canada); Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, ON, M5G 1X8 (Canada)

    2012-11-28

    Focal bone tumor treatments include amputation, limb-sparing surgical excision with bone reconstruction, and high-dose external-beam radiation therapy. Magnetic resonance guided high intensity focused ultrasound (MR-HIFU) is an effective non-invasive thermotherapy for palliative management of bone metastases pain. MR thermometry (MRT) measures the proton resonance frequency shift (PRFS) of water molecules and produces accurate (<1 Degree-Sign C) and dynamic (<5s) thermal maps in soft tissues. PRFS-MRT is ineffective in fatty tissues such as yellow bone marrow and, since accurate temperature measurements are required in the bone to ensure adequate thermal dose, MR-HIFU is not indicated for primary bone tumor treatments. Magnetic relaxation times are sensitive to lipid temperature and we hypothesize that bone marrow temperature can be determined accurately by measuring changes in T{sub 2}, since T{sub 2} increases linearly in fat during heating. T{sub 2}-mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T{sub 2}. Calibration of T{sub 2}-based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T{sub 2} and temperature with a thermocouple. A positive T{sub 2} temperature dependence in bone marrow of 20 ms/ Degree-Sign C was observed. Dynamic T{sub 2}-mapping should enable accurate temperature monitoring during MR-HIFU treatment of bone marrow and shows promise for improving the safety and reducing the invasiveness of pediatric bone tumor treatments.

  1. Cavitation-enhanced MR-guided focused ultrasound ablation of rabbit tumors in vivo using phase shift nanoemulsions

    Science.gov (United States)

    Kopechek, Jonathan A.; Park, Eun-Joo; Zhang, Yong-Zhi; Vykhodtseva, Natalia I.; McDannold, Nathan J.; Porter, Tyrone M.

    2014-07-01

    Advanced tumors are often inoperable due to their size and proximity to critical vascular structures. High intensity focused ultrasound (HIFU) has been developed to non-invasively thermally ablate inoperable solid tumors. However, the clinical feasibility of HIFU ablation therapy has been limited by the long treatment times (on the order of hours) and high acoustic intensities required. Studies have shown that inertial cavitation can enhance HIFU-mediated heating by generating broadband acoustic emissions that increase tissue absorption and accelerate HIFU-induced heating. Unfortunately, initiating inertial cavitation in tumors requires high intensities and can be unpredictable. To address this need, phase-shift nanoemulsions (PSNE) have been developed. PSNE consist of lipid-coated liquid perfluorocarbon droplets that are less than 200 nm in diameter, thereby allowing passive accumulation in tumors through leaky tumor vasculature. PSNE can be vaporized into microbubbles in tumors in order to nucleate cavitation activity and enhance HIFU-mediated heating. In this study, MR-guided HIFU treatments were performed on intramuscular rabbit VX2 tumors in vivo to assess the effect of vaporized PSNE on acoustic cavitation and HIFU-mediated heating. HIFU pulses were delivered for 30 s using a 1.5 MHz, MR-compatible transducer, and cavitation emissions were recorded with a 650 kHz ring hydrophone while temperature was monitored using MR thermometry. Cavitation emissions were significantly higher (P cavitation which correlates with enhanced HIFU-mediated heating in tumors. This suggests that PSNE could potentially be used to reduce the time and/or acoustic intensity required for HIFU-mediated heating, thereby increasing the feasibility and clinical efficacy of HIFU thermal ablation therapy.

  2. Pilot study: safety and effectiveness of simple ultrasound-guided high-intensity focused ultrasound ablating uterine leiomyoma with a diameter greater than 10 cm.

    Science.gov (United States)

    Hou, Ruijie; Wang, Liwei; Li, Shaoping; Rong, Fengmin; Wang, Yuanyuan; Qin, Xuena; Wang, Shijin

    2018-02-01

    The study aimed to prospectively investigate whether uterine leiomyoma greater than 10 cm in diameter could be treated with simple ultrasound-guided high-intensity focused ultrasound (USgHIFU) in one-time treatment. A total of 36 patients with 36 symptomatic uterine leiomyoma greater than 10 cm in diameter who underwent simple USgHIFU treatment alone were analysed. Enhanced MRI was performed before and after HIFU treatment, and all patients had follow-up for 6 months after treatment. Symptom severity scores, treatment time, treatment speed, ablation rate, energy effect ratio, uterine leiomyoma regression rate, adverse events, liver and kidney functions, coagulation function and routine blood count were included in the study endpoints. The mean diameter of uterine leiomyoma was 11.2 ± 1.3 cm (10.0-14.3 cm). The median treatment time and treatment speed were 104.0 min (90.0-140.0 min) and 118.8 cm 3  h -1  (86.2-247.1 cm 3  h -1 ), respectively. The ablation rate of uterine leiomyoma was 71.9 ± 20.4% (32.1-100.0%), and the regression rate of uterine leiomyoma was 40.8 ± 7.5% (25.6-59.9%) at 6 months after treatment. The mean symptom severity scores decreased by an average of approximately 8.6 ± 2.3 (5-14) points. There were no significant changes in haemogram and blood chemical indexes of patients, except for the transient elevation of aspartate aminotransferase, total bilirubin and white blood cells after treatment. No serious adverse reactions occurred. According to our preliminary results, simple USgHIFU is a safe and effective single-treatment method of treating uterine leiomyoma greater than 10 cm in diameter and is an almost innocuous alternative therapeutic strategy. Advances in knowledge: The conclusions indicate simple USgHIFU is safe and effective as one-time treatment of uterine leiomyoma greater than 10 cm in diameter, it could be a promising therapeutic strategy.

  3. Ultrasound guided high-intensity focused ultrasound combined with gonadotropin releasing hormone analogue (GnRHa) ablating uterine leiomyoma with homogeneous hyperintensity on T2 weighted MR imaging.

    Science.gov (United States)

    Yang, Shenghua; Kong, Fanjing; Hou, Ruijie; Rong, Fengmei; Ma, Nana; Li, Shaoping; Yang, Jun

    2017-05-01

    The study aimed to evaluate the safety and efficiency of ultrasound-guided high-intensity focused ultrasound (USgHIFU) combined with gonadotropin-releasing hormone analogue (GnRHa)-ablating symptomatic uterine leiomyoma with homogeneous hyperintensity on T 2 weighted MRI prospectively. A total of 34 patients with 42 symptomatic uterine leiomyomas with homogeneous hyperintensity on T 2 weighted MRI were enrolled in our study. In the patient who had multiple uterine leiomyomas, only one dominant leiomyoma was treated. According to the principles of voluntariness, 18 patients underwent a 3-month therapy of GnRHa (once a month) before the high-intensity focused ultrasound (HIFU) treatment, while 16 patients received only HIFU treatment. Enhanced MRI was performed before and after GnRHa and HIFU treatment. Evaluation of the main indicators included treatment time, sonication time, treatment efficiency, non-perfused volume (NPV) (indicative of successful ablation) ratio and energy effect ratio; adverse events were also recorded. The treatment time and sonication time of the combination group were 102.0 min (55.8-152.2 min) and 25.4 min (12.2-34.1 min); however, they were 149.0 min (87.0-210.0 min) and 38.9 min (14.0-46.7 min) in the simple USgHIFU group. The treatment and sonication time for the combination group was significantly shorter than that for the simple USgHIFU group. Treatment efficiency, NPV ratio and energy effect ratio were 46.7 mm 3  s -1 (28.5-95.8 mm 3  s -1 ), 69.2 ± 29.8% (35.5-97.4%) and 9.9 KJ mm -3 (4.5-15.7 KJ mm -3 ) in the combination group, respectively; but, the lowest treatment efficiency, lowest NPV ratio and more energy effect ratio were observed in the simple HIFU group, which were 16.8 mm 3  s -1 (8.9-32.9 mm 3  s -1 ), 50.2 ± 27.3% (0-78.6%) and 23.8 KJ mm -3 (12.4-46.2 KJ mm -3 ), respectively. Pain scores in the combination group were 3.0 ± 0.5 points (2-4 points

  4. Cavitation-enhanced MR-guided focused ultrasound ablation of rabbit tumors in vivo using phase shift nanoemulsions

    OpenAIRE

    Kopechek, Jonathan A; Park, Eun-Joo; Zhang, Yong-Zhi; Vykhodtseva, Natalia I; McDannold, Nathan J; Porter, Tyrone M

    2014-01-01

    Advanced tumors are often inoperable due to their size and proximity to critical vascular structures. High intensity focused ultrasound (HIFU) has been developed to non-invasively thermally ablate inoperable solid tumors. However, the clinical feasibility of HIFU ablation therapy has been limited by the long treatment times (on the order of hours) and high acoustic intensities required. Studies have shown that inertial cavitation can enhance HIFU-mediated heating by generating broadband acous...

  5. Magnetic Resonance–Guided High-Intensity Focused Ultrasound Hyperthermia for Recurrent Rectal Cancer: MR Thermometry Evaluation and Preclinical Validation

    Energy Technology Data Exchange (ETDEWEB)

    Chu, William, E-mail: William.Chu@sunnybrook.ca [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Staruch, Robert M. [Clinical Sites Research Program, Philips Research, Cambridge, Massachusetts (United States); Pichardo, Samuel [Thunder Bay Regional Research Institute, Thunder Bay, Ontario (Canada); Physics and Electrical Engineering, Lakehead University, Thunder Bay, Ontario (Canada); Tillander, Matti; Köhler, Max O. [MR Therapy, Philips Healthcare, Vantaa (Finland); Huang, Yuexi [Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Ylihautala, Mika [MR Therapy, Philips Healthcare, Vantaa (Finland); McGuffin, Merrylee [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Czarnota, Gregory [Department of Radiation Oncology, Sunnybrook Health Sciences Centre and the University of Toronto, Toronto, Ontario (Canada); Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada); Hynynen, Kullervo [Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario (Canada)

    2016-07-15

    Purpose: To evaluate the feasibility of magnetic resonance–guided high-intensity focused ultrasound (MR-HIFU) mild hyperthermia in deep tissue targets for enhancing radiation therapy and chemotherapy in the context of recurrent rectal cancer. A preclinical study was performed to evaluate the safety and performance of MR-HIFU mild hyperthermia. A prospective imaging study was performed in volunteers with rectal cancer to evaluate MR thermometry quality near the rectum and accessibility of rectal tumors using MR-HIFU. Methods and Materials: Mild hyperthermia was performed in pig thigh (9 sonications, 6 pigs) using a clinical MR-HIFU system. Targets near the rectal wall and deep thigh were evaluated. Thermal maps obtained in 6 planes every 3.2 seconds were used to control sonications in 18-mm diameter treatment regions at temperatures of 42°C to 42.5°C for 10 to 60 minutes. Volunteer imaging-only studies to assess the quality of MR thermometry (without heating) were approved by the institutional research ethics board. Anatomic and MR thermometry images were acquired in consenting volunteers with rectal cancer. In 3 of 6 study participants, rectal filling with saline was used to reduce motion-related MR thermometry artifacts near the tumor. Results: In pigs, mean target temperature matched the desired hyperthermia temperature within 0.2°C; temporal standard deviation ≤0.5°C. With optimized control thresholds, no undesired tissue damage was observed. In human volunteers, MR temperature measurements had adequate precision and stability, especially when rectal filling was used to reduce bowel motion. Conclusions: In pigs, MR-HIFU can safely deliver mild hyperthermia (41°C-43°C) to a targeted volume for 30 minutes. In humans, careful patient selection and preparation will enable adequate targeting for recurrent rectal cancers and sufficient MR temperature mapping stability to control mild hyperthermia. These results enable human trials of MR-HIFU hyperthermia.

  6. Clinical outcome of magnetic-resonance-guided focused ultrasound surgery (MRgFUS) in the treatment of symptomatic uterine fibroids

    International Nuclear Information System (INIS)

    Kamp, J.E.K.; Scheurig-Muenkler, C.; Beck, A.; David, M.; Hengst, S.

    2013-01-01

    Purpose: To investigate the clinical outcome of magnetic-resonance-guided focused ultrasound surgery (MRgFUS) treatment for symptomatic uterine fibroids in premenopausal women using the validated USF-QOL (Uterine Fibroid Symptom and Quality of Life) Questionnaire. Materials and Methods: 54 patients with symptomatic uterine fibroids were enrolled in this prospective study. The patients completed the UFS-QOL Questionnaire prior to MRgFUS treatment as well as after 3, 6, and 12 months. Results: The rate of technical success was 91.5 % (95.2 % after subtraction of screening errors). 6/54 patients (11 %) had other treatments (surgery, n = 4; UAE, n = 2), 8/54 (15 %) dropped out due to pregnancy, and 8/54 were lost to follow-up. The remaining group showed considerable symptom relief as early as after 3 months. The median overall quality of life score increased from 64.7 (quartile range QR: 49.8 - 77.6) before treatment to 77.6 (QR: 61.4 - 87.1) (p < 0.001), 78.4 (QR: 66.4 - 89.7) (p < 0.001), and 82.8 (QR: 69.8 - 92.2) (p < 0.001) at 3, 6, and 12 months, respectively. The corresponding median symptom severity score decreased from 46.9 (QR: 28.1 - 56.2) to 34.4 (QR: 21.9 - 43.7) at 3 months (p = 0.003) and 28.1 at 6 and 12 months (QR: 18.7 - 38.3, QR: 15.6 - 34.4) (p < 0.001, p = 0.002). The rate of complications requiring treatment was 9 %, and the rate of overall complications was 39 %. No major complications occurred. Conclusion: Our results indicate significant alleviation of fibroid-related symptoms within 12 months of MRgFUS with improvement beginning as early as 3 months after treatment. We observed no major complications, and some women became pregnant after MRgFUS. There was a low treatment failure rate of 11 %. (orig.)

  7. Magnetic Resonance–Guided High-Intensity Focused Ultrasound Hyperthermia for Recurrent Rectal Cancer: MR Thermometry Evaluation and Preclinical Validation

    International Nuclear Information System (INIS)

    Chu, William; Staruch, Robert M.; Pichardo, Samuel; Tillander, Matti; Köhler, Max O.; Huang, Yuexi; Ylihautala, Mika; McGuffin, Merrylee; Czarnota, Gregory; Hynynen, Kullervo

    2016-01-01

    Purpose: To evaluate the feasibility of magnetic resonance–guided high-intensity focused ultrasound (MR-HIFU) mild hyperthermia in deep tissue targets for enhancing radiation therapy and chemotherapy in the context of recurrent rectal cancer. A preclinical study was performed to evaluate the safety and performance of MR-HIFU mild hyperthermia. A prospective imaging study was performed in volunteers with rectal cancer to evaluate MR thermometry quality near the rectum and accessibility of rectal tumors using MR-HIFU. Methods and Materials: Mild hyperthermia was performed in pig thigh (9 sonications, 6 pigs) using a clinical MR-HIFU system. Targets near the rectal wall and deep thigh were evaluated. Thermal maps obtained in 6 planes every 3.2 seconds were used to control sonications in 18-mm diameter treatment regions at temperatures of 42°C to 42.5°C for 10 to 60 minutes. Volunteer imaging-only studies to assess the quality of MR thermometry (without heating) were approved by the institutional research ethics board. Anatomic and MR thermometry images were acquired in consenting volunteers with rectal cancer. In 3 of 6 study participants, rectal filling with saline was used to reduce motion-related MR thermometry artifacts near the tumor. Results: In pigs, mean target temperature matched the desired hyperthermia temperature within 0.2°C; temporal standard deviation ≤0.5°C. With optimized control thresholds, no undesired tissue damage was observed. In human volunteers, MR temperature measurements had adequate precision and stability, especially when rectal filling was used to reduce bowel motion. Conclusions: In pigs, MR-HIFU can safely deliver mild hyperthermia (41°C-43°C) to a targeted volume for 30 minutes. In humans, careful patient selection and preparation will enable adequate targeting for recurrent rectal cancers and sufficient MR temperature mapping stability to control mild hyperthermia. These results enable human trials of MR-HIFU hyperthermia.

  8. Effects of magnetic resonance-guided high-intensity focused ultrasound ablation on bone mechanical properties and modeling.

    Science.gov (United States)

    Yeo, Sin Yuin; Arias Moreno, Andrés J; van Rietbergen, Bert; Ter Hoeve, Natalie D; van Diest, Paul J; Grüll, Holger

    2015-01-01

    Magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) is a promising technique for palliative treatment of bone pain. In this study, the effects of MR-HIFU ablation on bone mechanics and modeling were investigated. A total of 12 healthy rat femurs were ablated using 10 W for 46 ± 4 s per sonication with 4 sonications for each femur. At 7 days after treatments, all animals underwent MR and single photon emission computed tomography/computed tomography (SPECT/CT) imaging. Then, six animals were euthanized. At 1 month following ablations, the remaining six animals were scanned again with MR and SPECT/CT prior to euthanization. Thereafter, both the HIFU-treated and contralateral control bones of three animals from each time interval were processed for histology, whereas the remaining bones were subjected to micro-CT (μCT), three-point bending tests, and micro-finite element (micro-FE) analyses. At 7 days after HIFU ablations, edema formation around the treated bones coupled with bone marrow and cortical bone necrosis was observed on MRI and histological images. SPECT/CT and μCT images revealed presence of bone modeling through an increased uptake of (99m)Tc-MDP and formation of woven bone, respectively. At 31 days after ablations, as illustrated by imaging and histology, healing of the treated bone and the surrounding soft tissue was noted, marked by decreased in amount of tissue damage, formation of scar tissue, and sub-periosteal reaction. The results of three-point bending tests showed no significant differences in elastic stiffness, ultimate load, and yield load between the HIFU-treated and contralateral control bones at 7 days and 1 month after treatments. Similarly, the elastic stiffness and Young's moduli determined by micro-FE analyses at both time intervals were not statistically different. Multimodality imaging and histological data illustrated the presence of HIFU-induced bone damage at the cellular level, which activated the

  9. Cavitation-enhanced MR-guided focused ultrasound ablation of rabbit tumors in vivo using phase shift nanoemulsions

    International Nuclear Information System (INIS)

    Kopechek, Jonathan A; Porter, Tyrone M; Park, Eun-Joo; Zhang, Yong-Zhi; Vykhodtseva, Natalia I; McDannold, Nathan J

    2014-01-01

    Advanced tumors are often inoperable due to their size and proximity to critical vascular structures. High intensity focused ultrasound (HIFU) has been developed to non-invasively thermally ablate inoperable solid tumors. However, the clinical feasibility of HIFU ablation therapy has been limited by the long treatment times (on the order of hours) and high acoustic intensities required. Studies have shown that inertial cavitation can enhance HIFU-mediated heating by generating broadband acoustic emissions that increase tissue absorption and accelerate HIFU-induced heating. Unfortunately, initiating inertial cavitation in tumors requires high intensities and can be unpredictable. To address this need, phase-shift nanoemulsions (PSNE) have been developed. PSNE consist of lipid-coated liquid perfluorocarbon droplets that are less than 200 nm in diameter, thereby allowing passive accumulation in tumors through leaky tumor vasculature. PSNE can be vaporized into microbubbles in tumors in order to nucleate cavitation activity and enhance HIFU-mediated heating. In this study, MR-guided HIFU treatments were performed on intramuscular rabbit VX2 tumors in vivo to assess the effect of vaporized PSNE on acoustic cavitation and HIFU-mediated heating. HIFU pulses were delivered for 30 s using a 1.5 MHz, MR-compatible transducer, and cavitation emissions were recorded with a 650 kHz ring hydrophone while temperature was monitored using MR thermometry. Cavitation emissions were significantly higher (P < 0.05) after PSNE injection and this was well correlated with enhanced HIFU-mediated heating in tumors. The peak temperature rise induced by sonication was significantly higher (P < 0.05) after PSNE injection. For example, the mean per cent change in temperature achieved at 5.2 W of acoustic power was 46 ± 22% with PSNE injection. The results indicate that PSNE nucleates cavitation which correlates with enhanced HIFU-mediated heating in tumors. This suggests that PSNE could

  10. [Magnetic resonance guided focused ultrasound surgery for pain palliation of bone metastases: early experience of clinical application in China].

    Science.gov (United States)

    Gu, Jianjun; Wang, Han; Tang, Na; Hua, Yingqi; Yang, Haiyan; Qiu, Yimin; Ge, Renbin; Zhou, Ying; Wang, Wenwen; Zhang, Guixiang

    2015-11-03

    To evaluate the safety and efficacy of magnetic resonance guided focused ultrasound surgery (MRgFUS) in treatment for pain palliation of bone metastases. Eighty-one patients of painful bone metastases were volunteered to screen for this study in Shanghai General Hospital from June 2014 to February 2015. Twenty-three patients among them were treated by MRgFUS, who was more than 18-years old, having the ability to fully understand the informed consent of the research, suffering with pain of numeric rating scale (NRS) ≥ 4, non-received radiotherapy or chemotherapy for pain palliation of bone metastases in the past two weeks. The NRS, the standard question of Brief Pain Inventory (BPI-QoL), and the standard question of Europe Organization for Research and Treatment of Cancer Quality of Life Questionnaire- Bone Metastases 22 (EORTC QLQ-BM22) were respectively recorded before and 1-week, 1-month, 3-month after the treatment. The related adverse events of MRgFUS were observed and recorded in 3 months after the treatment as well. (1)Twenty-three metastatic bone tumor lesions of 23 patients were treated by MRgFUS, the treatment data was as follows: the mean treatment time was (88 ± 33) minutes, the mean sonication number was 13 ± 8. (2) Adverse events included: pain in therapy area 3/23, which spontaneous relieving within one week; numbness in lower limb (1/23), which relieved after physiotherapy. (3) The NRS of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 6.0 ± 1.5, 3.7 ± 1.7,3.1 ± 2.0, and 2.2 ± 1.0,which significantly decreased after the treatment (P<0.01). (4) The BPI-QoL score of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 39 ± 16, 27 ± 18, 26 ± 18, and 21 ± 18, which significantly decreased after the treatment (P<0.01). (5) The EORTC QLQ-BM22 score of before treatment and at 1-week, 1-month, and 3-month after treatment respectively was 52 ± 13, 44 ± 12, 42 ± 12, and 39

  11. Patient selection guidelines in MR-guided focused ultrasound surgery of uterine fibroids: a pictorial guide to relevant findings in screening pelvic MRI

    International Nuclear Information System (INIS)

    Yoon, Sang-Wook; Kim, Kyoung Ah; Lee, Chan; Na, Young-Jeong; Jung, Sang-Geun; Kim, Seung-Jo; Cha, Sun Hee; Yu, Jeong-Sik

    2008-01-01

    Uterine leiomyomas (fibroids), the most common benign tumor in women of childbearing age, can cause symptoms including dysmenorrhea, menorrhagia, urinary symptoms, pain and infertility. Hysterectomy is a common approach to treating uterine fibroids, and less invasive surgical approaches such as myomectomy and uterine artery embolization also have been shown to alleviate symptoms. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is the only totally non-invasive surgical approved method for treating uterine fibroids. In clinical trials, MRgFUS resulted in significant relief of uterine fibroid symptoms. The safe and effective use of MRgFUS is affected by fibroid type and location, position relative to adjacent anatomical structures and the presence of co-existent pelvic disease. Additionally, successful outcomes with MRgFUS have been correlated with the volume of fibroids ablated during the procedure. Thus, selection of patients in whom sufficient fibroid volumes can be treated safely using the MRgFUS system is critical for successful outcomes. The MR images in this pictorial essay provide examples of uterine fibroids for which MRgFUS should be considered and is designed to facilitate the selection of patients for whom MRgFUS is most likely to provide sustained symptom relief. (orig.)

  12. Patient selection guidelines in MR-guided focused ultrasound surgery of uterine fibroids: a pictorial guide to relevant findings in screening pelvic MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sang-Wook; Kim, Kyoung Ah [Pochon CHA University Bundang CHA General Hospital, Department of Diagnostic Radiology, College of Medicine, Gyunggi-do (Korea); Lee, Chan; Na, Young-Jeong; Jung, Sang-Geun; Kim, Seung-Jo [Pochon CHA University Bundang CHA General Hospital, Comprehensive Gynecologic Cancer Center, College of Medicine, Gyunggi-do (Korea); Cha, Sun Hee [Pochon CHA University Bundang CHA General Hospital, Department of Obstetrics and Gynecology, College of Medicine, Gyunggi-do (Korea); Yu, Jeong-Sik [YongDong Severance Hospital, Department of Diagnostic Radiology, Yonsei University College of Medicine, Seoul (Korea)

    2008-12-15

    Uterine leiomyomas (fibroids), the most common benign tumor in women of childbearing age, can cause symptoms including dysmenorrhea, menorrhagia, urinary symptoms, pain and infertility. Hysterectomy is a common approach to treating uterine fibroids, and less invasive surgical approaches such as myomectomy and uterine artery embolization also have been shown to alleviate symptoms. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is the only totally non-invasive surgical approved method for treating uterine fibroids. In clinical trials, MRgFUS resulted in significant relief of uterine fibroid symptoms. The safe and effective use of MRgFUS is affected by fibroid type and location, position relative to adjacent anatomical structures and the presence of co-existent pelvic disease. Additionally, successful outcomes with MRgFUS have been correlated with the volume of fibroids ablated during the procedure. Thus, selection of patients in whom sufficient fibroid volumes can be treated safely using the MRgFUS system is critical for successful outcomes. The MR images in this pictorial essay provide examples of uterine fibroids for which MRgFUS should be considered and is designed to facilitate the selection of patients for whom MRgFUS is most likely to provide sustained symptom relief. (orig.)

  13. Successful Use of Magnetic Resonance-Guided Focused Ultrasound Surgery for Long-Term Pain Palliation in a Patient Suffering from Metastatic Bone Tumor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Eun; Yoon, Sang Wook; Kim, Kyoung Ah; Lee, Jong Tae [Dept. of Diagnostic Radiology, CHA Bundang Medical Center, CHA University College of Medicine, Seongnam (Korea, Republic of); Shay, Lilach [InSightec. Ltd, Hifa, (Israel); Lee, Kyong Sik [Dept. of General Surgery, CHA Bundang Medical Center, CHA University College of Medicine, Seongnam (Korea, Republic of)

    2011-08-15

    Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a clinically effective, non-invasive treatment for thermal ablation of various soft tissue tumors, and is effective in pain palliation following radiation therapy, as has been demonstrated in the initial studies of bone metastases. The current study evaluated the safety and clinical efficacy of MRgFUS for pain palliation prior to radiation therapy, in a patient with a solitary metastatic bone lesion. This is the first case report of MRgFUS treatment with a 1-year follow-up in a patient.

  14. Successful Use of Magnetic Resonance-Guided Focused Ultrasound Surgery for Long-Term Pain Palliation in a Patient Suffering from Metastatic Bone Tumor

    International Nuclear Information System (INIS)

    Lee, Ji Eun; Yoon, Sang Wook; Kim, Kyoung Ah; Lee, Jong Tae; Shay, Lilach; Lee, Kyong Sik

    2011-01-01

    Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a clinically effective, non-invasive treatment for thermal ablation of various soft tissue tumors, and is effective in pain palliation following radiation therapy, as has been demonstrated in the initial studies of bone metastases. The current study evaluated the safety and clinical efficacy of MRgFUS for pain palliation prior to radiation therapy, in a patient with a solitary metastatic bone lesion. This is the first case report of MRgFUS treatment with a 1-year follow-up in a patient.

  15. Opening the Blood-Brain Barrier with MR Imaging-guided Focused Ultrasound: Preclinical Testing on a Trans-Human Skull Porcine Model.

    Science.gov (United States)

    Huang, Yuexi; Alkins, Ryan; Schwartz, Michael L; Hynynen, Kullervo

    2017-01-01

    Purpose To develop and test a protocol in preparation for a clinical trial on opening the blood-brain barrier (BBB) with magnetic resonance (MR) imaging-guided focused ultrasound for the delivery of chemotherapy drugs to brain tumors. Materials and Methods The procedures were approved by the institutional animal care committee. A trans-human skull porcine model was designed for the preclinical testing. Wide craniotomies were applied in 11 pigs (weight, approximately 15 kg). A partial human skull was positioned over the animal's brain. A modified clinical MR imaging-guided focused ultrasound brain system was used with a 3.0-T MR unit. The ultrasound beam was steered during sonications over a 3 × 3 grid at 3-mm spacing. Acoustic power levels of 3-20 W were tested. Bolus injections of microbubbles at 4 μL/kg were tested for each sonication. Levels of BBB opening, hemorrhage, and cavitation signal were measured with MR imaging, histologic examination, and cavitation receivers, respectively. A cavitation safety algorithm was developed on the basis of logistic regression of the measurements and tested to minimize the risk of hemorrhage. Results BBB openings of approximately 1 cm 3 in volume were visualized with gadolinium-enhanced MR imaging after sonication at an acoustic power of approximately 5 W. Gross examination of histologic specimens helped confirm Evans blue (bound to macromolecule albumin) extravasation, and hematoxylin-eosin staining helped detect only scattered extravasation of red blood cells. In cases where cavitation signals were higher than thresholds, sonications were terminated immediately without causing hemorrhage. Conclusion With a trans-human skull porcine model, this study demonstrated BBB opening with a 230-kHz system in preparation for a clinical trial. © RSNA, 2016 Online supplemental material is available for this article.

  16. MR-guided focused ultrasound. Current and future applications; MR-gesteuerter fokussierter Ultraschall. Aktuelle und potenzielle Indikationen

    Energy Technology Data Exchange (ETDEWEB)

    Trumm, C.G.; Peller, M.; Clevert, D.A.; Stahl, R.; Reiser, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen-Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Napoli, A. [Sapienza Universitaet Rom, Abteilung fuer Radiologie (Department of Radiological Sciences), MRgFUS and Cardiovascular Imaging Unit, Rom (Italy); Matzko, M. [Klinikum Dachau, Abteilung fuer diagnostische und interventionelle Radiologie, Dachau (Germany)

    2013-03-15

    High-intensity focused ultrasound (synonyms FUS and HIFU) under magnetic resonance imaging (MRI) guidance (synonyms MRgFUS and MR-HIFU) is a completely non-invasive technology for accurate thermal ablation of a target tissue while neighboring tissues and organs are preserved. The combination of FUS with MRI for planning, (near) real-time monitoring and outcome assessment of treatment markedly enhances the safety of the procedure. The MRgFUS procedure is clinically established in particular for the treatment of symptomatic uterine fibroids, followed by palliative ablation of painful bone metastases. Furthermore, promising results have been shown for the treatment of adenomyosis, malignant tumors of the prostate, breast and liver and for various intracranial applications, such as thermal ablation of brain tumors, functional neurosurgery and transient disruption of the blood-brain barrier. (orig.) [German] MRT-gesteuerter hochintensiver fokussierter Ultraschall (MRgFUS bzw. MR-HIFU) ist ein nichtinvasives Verfahren zur praezisen Thermoablation eines Zielgewebes. Bei dieser Methode werden benachbarte Gewebe und Organe geschont. Die Kombination des fokussierten Ultraschalls (FUS) mit der MRT zwecks Planung und Monitoring (nahezu) in Echtzeit sowie zur Erfolgskontrolle von Behandlungen traegt wesentlich zur Sicherheit dieser Methode bei. MRgFUS ist klinisch v. a. zur Behandlung von symptomatischen Uterusmyomen etabliert, gefolgt von der palliativen Ablation von Knochenmetastasen. Weitere vielversprechende Anwendungsgebiete des MRgFUS sind die Adenomyose des Uterus, die Behandlung von Prostata-, Mamma- und Lebertumoren sowie der intrakranielle Einsatz. (orig.)

  17. Feasibility of magnetic resonance imaging-guided high intensity focused ultrasound therapy for ablating uterine fibroids in patients with bowel lies anterior to uterus

    International Nuclear Information System (INIS)

    Zhang Lian; Chen Wenzhi; Liu Yinjiang; Hu Xiao; Zhou Kun; Chen Li; Peng Song; Zhu Hui; Zou Huiling; Bai Jin; Wang Zhibiao

    2010-01-01

    Purpose: To prospectively evaluate the feasibility of magnetic resonance (MR) imaging-guided high intensity focused ultrasound (HIFU) therapeutic ablation of uterine fibroids in patients with bowel lies anterior to uterus. Materials and methods: Twenty-one patients with 23 uterine fibroids underwent MR imaging-guided high intensity focused ultrasound treatment, with a mean age of 39.4 ± 6.9 (20-49) years, with fibroids average measuring 6.0 ± 1.6 (range, 2.9-9.5) cm in diameter. After being compressed with a degassed water balloon on abdominal wall, MR imaging-guided high intensity focused ultrasound treatment was performed under conscious sedation by using fentanyl and midazolam. This procedure was performed by a Haifu JM focused ultrasound tumour therapeutic system (JM2.5C, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Symphony, Siemens, Germany), which provides real-time guidance and control. Contrast-enhanced MR imaging was performed to evaluate the efficacy of thermal ablation immediately and 3 months after HIFU treatment. The treatment time and adverse events were recorded. Results: The mean fibroid volume was 97.0 ± 78.3 (range, 12.7-318.3) cm 3 . According to the treatment plan, an average 75.0 ± 11.4% (range, 37.8-92.4%) of the fibroid volume was treated. The mean fibroid volume immediately after HIFU was 109.7 ± 93.1 (range, 11.9-389.6) cm 3 , slightly enlarged because of edema. The average non-perfused volume was 83.3 ± 71.7 (range, 7.7-282.9) cm 3 , the average fractional ablation, which was defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 76.9 ± 18.7% (range, 21.0-97.0%). There were no statistically significant differences between the treatment volume and the non-perfused volume. Follow-up magnetic resonance imaging (MRI) at 3 months obtained in 12 patients, the fibroid volume decreased by 31.4 ± 29.3% (range, -1.9 to 60.0%) in average, with paired t

  18. Feasibility of magnetic resonance imaging-guided high intensity focused ultrasound therapy for ablating uterine fibroids in patients with bowel lies anterior to uterus

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lian; Chen Wenzhi [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Liu Yinjiang; Hu Xiao [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Zhou Kun [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Chen Li [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Peng Song; Zhu Hui [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); Zou Huiling [National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Bai Jin [Institute of Ultrasound Engineering in Medicine of Chongqing University of Medical Sciences, Chongqing 400016 (China); Wang Zhibiao [Clinical Center for Tumour Therapy of 2nd Affiliated Hospital of Chongqing University of Medical Sciences, Chongqing 400010 (China); National Engineering Research Center of Ultrasound Medicine, Chongqing 400010 (China); Institute of Ultrasound Engineering in Medicine of Chongqing University of Medical Sciences, Chongqing 400016 (China)], E-mail: wangzhibiao@haifu.com.cn

    2010-02-15

    Purpose: To prospectively evaluate the feasibility of magnetic resonance (MR) imaging-guided high intensity focused ultrasound (HIFU) therapeutic ablation of uterine fibroids in patients with bowel lies anterior to uterus. Materials and methods: Twenty-one patients with 23 uterine fibroids underwent MR imaging-guided high intensity focused ultrasound treatment, with a mean age of 39.4 {+-} 6.9 (20-49) years, with fibroids average measuring 6.0 {+-} 1.6 (range, 2.9-9.5) cm in diameter. After being compressed with a degassed water balloon on abdominal wall, MR imaging-guided high intensity focused ultrasound treatment was performed under conscious sedation by using fentanyl and midazolam. This procedure was performed by a Haifu JM focused ultrasound tumour therapeutic system (JM2.5C, Chongqing Haifu Technology Co., Ltd., China), in combination with a 1.5-Tesla MRI system (Symphony, Siemens, Germany), which provides real-time guidance and control. Contrast-enhanced MR imaging was performed to evaluate the efficacy of thermal ablation immediately and 3 months after HIFU treatment. The treatment time and adverse events were recorded. Results: The mean fibroid volume was 97.0 {+-} 78.3 (range, 12.7-318.3) cm{sup 3}. According to the treatment plan, an average 75.0 {+-} 11.4% (range, 37.8-92.4%) of the fibroid volume was treated. The mean fibroid volume immediately after HIFU was 109.7 {+-} 93.1 (range, 11.9-389.6) cm{sup 3}, slightly enlarged because of edema. The average non-perfused volume was 83.3 {+-} 71.7 (range, 7.7-282.9) cm{sup 3}, the average fractional ablation, which was defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 76.9 {+-} 18.7% (range, 21.0-97.0%). There were no statistically significant differences between the treatment volume and the non-perfused volume. Follow-up magnetic resonance imaging (MRI) at 3 months obtained in 12 patients, the fibroid volume decreased by 31.4 {+-} 29.3% (range, -1.9 to 60

  19. Fast lesion mapping during HIFU treatment using harmonic motion imaging guided focused ultrasound (HMIgFUS) in vitro and in vivo

    Science.gov (United States)

    Han, Yang; Wang, Shutao; Payen, Thomas; Konofagou, Elisa

    2017-04-01

    The successful clinical application of high intensity focused ultrasound (HIFU) ablation depends on reliable monitoring of the lesion formation. Harmonic motion imaging guided focused ultrasound (HMIgFUS) is an ultrasound-based elasticity imaging technique, which monitors HIFU ablation based on the stiffness change of the tissue instead of the echo intensity change in conventional B-mode monitoring, rendering it potentially more sensitive to lesion development. Our group has shown that predicting the lesion location based on the radiation force-excited region is feasible during HMIgFUS. In this study, the feasibility of a fast lesion mapping method is explored to directly monitor the lesion map during HIFU. The harmonic motion imaging (HMI) lesion map was generated by subtracting the reference HMI image from the present HMI peak-to-peak displacement map, as streamed on the computer display. The dimensions of the HMIgFUS lesions were compared against gross pathology. Excellent agreement was found between the lesion depth (r 2  =  0.81, slope  =  0.90), width (r 2  =  0.85, slope  =  1.12) and area (r 2  =  0.58, slope  =  0.75). In vivo feasibility was assessed in a mouse with a pancreatic tumor. These findings demonstrate that HMIgFUS can successfully map thermal lesions and monitor lesion development in real time in vitro and in vivo. The HMIgFUS technique may therefore constitute a novel clinical tool for HIFU treatment monitoring.

  20. [Ultrasound-guided peripheral catheterization].

    Science.gov (United States)

    Salleras-Duran, Laia; Fuentes-Pumarola, Concepció

    2016-01-01

    Peripheral catheterization is a technique that can be difficult in some patients. Some studies have recently described the use of ultrasound to guide the venous catheterization. To describe the success rate, time required, complications of ultrasound-guided peripheral venous catheterization. and patients and professionals satisfaction The search was performed in databases (Medline-PubMed, Cochrane Library, CINAHL and Cuiden Plus) for studies published about ultrasound-guided peripheral venous catheterization performed on patients that provided results on the success of the technique, complications, time used, patient satisfaction and the type of professional who performed the technique. A total of 21 studies were included. Most of them get a higher success rate 80% in the catheterization ecoguide and time it is not higher than the traditional technique. The Technical complications analyzed were arterial puncture rates and lower nerve 10%. In all studies measuring and comparing patient satisfaction in the art ecoguide is greater. Various professional groups perform the technique. The use of ultrasound for peripheral pipes has a high success rate, complications are rare and the time used is similar to that of the traditional technique. The technique of inserting catheters through ultrasound may be learned by any professional group performing venipuncture. Finally, it gets underscores the high patient satisfaction with the use of this technique. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  1. A dual-mode hemispherical sparse array for 3D passive acoustic mapping and skull localization within a clinical MRI guided focused ultrasound device

    Science.gov (United States)

    Crake, Calum; Brinker, Spencer T.; Coviello, Christian M.; Livingstone, Margaret S.; McDannold, Nathan J.

    2018-03-01

    Previous work has demonstrated that passive acoustic imaging may be used alongside MRI for monitoring of focused ultrasound therapy. However, past implementations have generally made use of either linear arrays originally designed for diagnostic imaging or custom narrowband arrays specific to in-house therapeutic transducer designs, neither of which is fully compatible with clinical MR-guided focused ultrasound (MRgFUS) devices. Here we have designed an array which is suitable for use within an FDA-approved MR-guided transcranial focused ultrasound device, within the bore of a 3 Tesla clinical MRI scanner. The array is constructed from 5  ×  0.4 mm piezoceramic disc elements arranged in pseudorandom fashion on a low-profile laser-cut acrylic frame designed to fit between the therapeutic elements of a 230 kHz InSightec ExAblate 4000 transducer. By exploiting thickness and radial resonance modes of the piezo discs the array is capable of both B-mode imaging at 5 MHz for skull localization, as well as passive reception at the second harmonic of the therapy array for detection of cavitation and 3D passive acoustic imaging. In active mode, the array was able to perform B-mode imaging of a human skull, showing the outer skull surface with good qualitative agreement with MR imaging. Extension to 3D showed the array was able to locate the skull within  ±2 mm/2° of reference points derived from MRI, which could potentially allow registration of a patient to the therapy system without the expense of real-time MRI. In passive mode, the array was able to resolve a point source in 3D within a  ±10 mm region about each axis from the focus, detect cavitation (SNR ~ 12 dB) at burst lengths from 10 cycles to continuous wave, and produce 3D acoustic maps in a flow phantom. Finally, the array was used to detect and map cavitation associated with microbubble activity in the brain in nonhuman primates.

  2. Neuronavigation-guided focused ultrasound-induced blood-brain barrier opening: A preliminary study in swine

    Science.gov (United States)

    Liu, Hao-Li; Tsai, Hong-Chieh; Lu, Yu-Jen; Wei, Kuo-Chen

    2012-11-01

    FUS-induced BBB opening is a promising technique for noninvasive and local delivery of drugs into the brain. Here we propose the novel use of a neuronavigation system to guide the FUS-induced BBB opening procedure, and investigate its feasibility in vivo in large animals. We developed an interface between the neuronavigator and FUS to allow guidance of the focal energy produced by the FUS transducer. The system was tested in 29 pigs by more than 40 sonication procedures and evaluated by MRI. Gd-DTPA concentration was quantitated in vivo by MRI R1 relaxometry and compared by ICP-OES assay. Brain histology after FUS exposure was investigated by HE and TUNEL staining. Neuronavigation could successfully guide the focal beam with comparable precision to neurosurgical stereotactic procedures (2.3 ± 0.9 mm). FUS pressure of 0.43 MPa resulted in consistent BBB-opening. Neuronavigation-guided BBB-opening increased Gd-DTPA deposition by up to 1.83 mM (140% increase). MR relaxometry demonstrated high correlation to ICP-OES measurements (r2 = 0.822), suggesting that Gd-DTPA deposition can be directly measured by imaging. Neuronavigation could provide sufficient precision for guiding FUS to temporally and locally open the BBB. Gd-DTPA deposition in the brain could be quantified by MR relaxometry, providing a potential tool for the in vivo quantification of therapeutic agents in CNS disease treatment.

  3. Ultrashort echo-time MRI versus CT for skull aberration correction in MR-guided transcranial focused ultrasound: In vitro comparison on human calvaria.

    Science.gov (United States)

    Miller, G Wilson; Eames, Matthew; Snell, John; Aubry, Jean-François

    2015-05-01

    Transcranial magnetic resonance-guided focused ultrasound (TcMRgFUS) brain treatment systems compensate for skull-induced beam aberrations by adjusting the phase and amplitude of individual ultrasound transducer elements. These corrections are currently calculated based on a preacquired computed tomography (CT) scan of the patient's head. The purpose of the work presented here is to demonstrate the feasibility of using ultrashort echo-time magnetic resonance imaging (UTE MRI) instead of CT to calculate and apply aberration corrections on a clinical TcMRgFUS system. Phantom experiments were performed in three ex-vivo human skulls filled with tissue-mimicking hydrogel. Each skull phantom was imaged with both CT and UTE MRI. The MR images were then segmented into "skull" and "not-skull" pixels using a computationally efficient, threshold-based algorithm, and the resulting 3D binary skull map was converted into a series of 2D virtual CT images. Each skull was mounted in the head transducer of a clinical TcMRgFUS system (ExAblate Neuro, Insightec, Israel), and transcranial sonications were performed using a power setting of approximately 750 acoustic watts at several different target locations within the electronic steering range of the transducer. Each target location was sonicated three times: once using aberration corrections calculated from the actual CT scan, once using corrections calculated from the MRI-derived virtual CT scan, and once without applying any aberration correction. MR thermometry was performed in conjunction with each 10-s sonication, and the highest single-pixel temperature rise and surrounding-pixel mean were recorded for each sonication. The measured temperature rises were ∼ 45% larger for aberration-corrected sonications than for noncorrected sonications. This improvement was highly significant (p skull-induced ultrasound aberration corrections. Their results suggest that UTE MRI could be used instead of CT to implement such corrections on

  4. MRI-guided focused ultrasound (MRgFUS) to treat facet joint osteoarthritis low back pain - case series of an innovative new technique

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, Evan M.; Platt, Michael W. [St Mary' s Hospital, Imperial College Healthcare NHS Trust, Department of Anaesthesia and Pain Medicine, London (United Kingdom); Gedroyc, Wladyslaw [St Mary' s Hospital, Imperial College Healthcare NHS Trust, Department of Radiology, London (United Kingdom)

    2012-12-15

    To evaluate the safety and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) to treat facet joint osteoarthritis pain. Patients with a positive response to facet joint interventions were recruited from Pain and Spinal Clinics. Treatments were performed at the levels of pain according to symptomatology, previous invasive treatment and MRI grading of facet joint osteoarthritis. Both safety and efficacy data were collected. Pain palliation was evaluated using a validated pain numerical rating scale (NRS), Oswestry disability questionnaire (ODQ), Brief Pain Inventory (BPI) and the EuroQol (EQ-5D) health state score Eighteen patients were treated. There were no major adverse events. At 6/12 we found a reduction in both the NRS (average/worst) pain scores (60.2 %/51.2 %). This was associated with 45.9 % improvement in the ODQ score and 61.9 % reduction in the BPI interference score. We observed an improvement in the EuroQol (EQ-5D) health state score based on UK coefficients of +0.379 (0.317 to 0.696). Our phase I observational pilot study has evaluated an innovative new technique that is both non-invasive and radiation free. It is the first description of this procedure in the literature. In all patients the technique was safe, free of complications, effective and well tolerated. (orig.)

  5. Improved survival in rats with glioma using MRI-guided focused ultrasound and microbubbles to disrupt the blood-brain barrier and deliver Doxil

    Science.gov (United States)

    Aryal, Muna; Zhi Zhang, Yong; Vykhodtseva, Natalia; Park, Juyoung; Power, Chanikarn; McDannold, Nathan

    2012-02-01

    Blood-brain-barrier (BBB) limits the transportation of most neuropeptides, proteins (enzymes, antibodies), chemotherapeutic agents, and genes that have therapeutic potential for the treatment of brain diseases. Different methods have been used to overcome this limitation, but they are invasive, non-targeted, or require the development of new drugs. We have developed a method that uses MRI-guided focused ultrasound (FUS) combined with circulating microbubbles to temporarily open BBB in and around brain tumors to deliver chemotherapy agents. Here, we tested whether this noninvasive technique could enhance the effectiveness of a chemotherapy agent (Doxil). Using 690 kHz FUS transducer and microbubble (Definity), we induced BBB disruption in intracranially-implanted 9L glioma tumors in rat's brain in three weekly sessions. Animals who received BBB disruption and Doxil had a median survival time of 34.5 days, which was significantly longer than that found in control animals which is 16, 18.5, 21 days who received no treatment, BBB disruption only and Doxil only respectively This work demonstrates that FUS technique has promise in overcoming barriers to drug delivery, which are particularly stark in the brain due to the BBB.

  6. MRI-guided focused ultrasound (MRgFUS) to treat facet joint osteoarthritis low back pain - case series of an innovative new technique

    International Nuclear Information System (INIS)

    Weeks, Evan M.; Platt, Michael W.; Gedroyc, Wladyslaw

    2012-01-01

    To evaluate the safety and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) to treat facet joint osteoarthritis pain. Patients with a positive response to facet joint interventions were recruited from Pain and Spinal Clinics. Treatments were performed at the levels of pain according to symptomatology, previous invasive treatment and MRI grading of facet joint osteoarthritis. Both safety and efficacy data were collected. Pain palliation was evaluated using a validated pain numerical rating scale (NRS), Oswestry disability questionnaire (ODQ), Brief Pain Inventory (BPI) and the EuroQol (EQ-5D) health state score Eighteen patients were treated. There were no major adverse events. At 6/12 we found a reduction in both the NRS (average/worst) pain scores (60.2 %/51.2 %). This was associated with 45.9 % improvement in the ODQ score and 61.9 % reduction in the BPI interference score. We observed an improvement in the EuroQol (EQ-5D) health state score based on UK coefficients of +0.379 (0.317 to 0.696). Our phase I observational pilot study has evaluated an innovative new technique that is both non-invasive and radiation free. It is the first description of this procedure in the literature. In all patients the technique was safe, free of complications, effective and well tolerated. (orig.)

  7. Cranial nerve threshold for thermal injury induced by MRI-guided high-intensity focused ultrasound (MRgHIFU): preliminary results on an optic nerve model.

    Science.gov (United States)

    Harnof, Sagi; Zibly, Zion; Cohen, Zvi; Shaw, Andrew; Schlaff, Cody; Kassel, Neal F

    2013-04-01

    Future clinical applications of magnetic resonance imaging-guided high-intensity focused ultrasound (MRgHIFU) are moving toward the management of different intracranial pathologies. We sought to validate the production, safety, and efficacy of thermal injury to cranial nerves generated by MRgHIFU. In this study, five female domestic pigs underwent a standard bifrontal craniectomy under general anesthesia. Treatment was then given using an MRgHIFU system to induce hyperthermic ablative sonication (6 to 10 s; 50 to 2000 J.) Histological analyses were done to confirm nerve damage; temperature measured on the optic nerve was approximately 53.4°C (range: 39°C to 70°C.) Histology demonstrated a clear definition between a necrotic, transitional zone, and normal tissue. MRgHIFU induces targeted thermal injury to nervous tissue within a specific threshold of 50°C to 60°C with the tissue near the sonication center yielding the greatest effect; adjacent tissue showed minimal changes. Additional studies utilizing this technology are required to further establish accurate threshold parameters for optic nerve thermo-ablation.

  8. Volumetric MR-Guided High-Intensity Focused Ultrasound with Direct Skin Cooling for the Treatment of Symptomatic Uterine Fibroids: Proof-of-Concept Study

    Directory of Open Access Journals (Sweden)

    Marlijne E. Ikink

    2015-01-01

    Full Text Available Objective. To prospectively assess the safety and technical feasibility of volumetric magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU ablation with direct skin cooling (DISC during treatment of uterine fibroids. Methods. In this proof-of-concept study, eight patients were consecutively selected for clinical MR-HIFU ablation of uterine fibroids with the use of an additional DISC device to maintain a constant temperature (T≈20°C at the interface between the HIFU table top and the skin. Technical feasibility was verified by successful completion of MR-HIFU ablation. Contrast-enhanced T1-weighted MRI was used to measure the treatment effect (nonperfused volume (NPV ratio. Safety was evaluated by recording of adverse events (AEs within 30 days’ follow-up. Results. All MR-HIFU treatments were successfully completed in an outpatient setting. The median NPV ratio was 0.56 (IQR [0.27–0.72]. Immediately after treatment, two patients experienced coldness related discomfort which resolved at the same day. No serious (device-related AEs were reported. Specifically, no skin burns, cold injuries, or subcutaneous edema were observed. Conclusion. This study showed that it is safe and technically feasible to complete a volumetric MR-HIFU ablation with DISC. This technique may reduce the risk of thermal injury to the abdominal wall during MR-HIFU ablation of uterine fibroids. This trial is registered with NTR4189.

  9. Intracranial inertial cavitation threshold and thermal ablation lesion creation using MRI-guided 220-kHz focused ultrasound surgery: preclinical investigation.

    Science.gov (United States)

    Xu, Zhiyuan; Carlson, Carissa; Snell, John; Eames, Matt; Hananel, Arik; Lopes, M Beatriz; Raghavan, Prashant; Lee, Cheng-Chia; Yen, Chun-Po; Schlesinger, David; Kassell, Neal F; Aubry, Jean-Francois; Sheehan, Jason

    2015-01-01

    In biological tissues, it is known that the creation of gas bubbles (cavitation) during ultrasound exposure is more likely to occur at lower rather than higher frequencies. Upon collapsing, such bubbles can induce hemorrhage. Thus, acoustic inertial cavitation secondary to a 220-kHz MRI-guided focused ultrasound (MRgFUS) surgery is a serious safety issue, and animal studies are mandatory for laying the groundwork for the use of low-frequency systems in future clinical trials. The authors investigate here the in vivo potential thresholds of MRgFUS-induced inertial cavitation and MRgFUS-induced thermal coagulation using MRI, acoustic spectroscopy, and histology. Ten female piglets that had undergone a craniectomy were sonicated using a 220-kHz transcranial MRgFUS system over an acoustic energy range of 5600-14,000 J. For each piglet, a long-duration sonication (40-second duration) was performed on the right thalamus, and a short sonication (20-second duration) was performed on the left thalamus. An acoustic power range of 140-300 W was used for long-duration sonications and 300-700 W for short-duration sonications. Signals collected by 2 passive cavitation detectors were stored in memory during each sonication, and any subsequent cavitation activity was integrated within the bandwidth of the detectors. Real-time 2D MR thermometry was performed during the sonications. T1-weighted, T2-weighted, gradient-recalled echo, and diffusion-weighted imaging MRI was performed after treatment to assess the lesions. The piglets were killed immediately after the last series of posttreatment MR images were obtained. Their brains were harvested, and histological examinations were then performed to further evaluate the lesions. Two types of lesions were induced: thermal ablation lesions, as evidenced by an acute ischemic infarction on MRI and histology, and hemorrhagic lesions, associated with inertial cavitation. Passive cavitation signals exhibited 3 main patterns identified as

  10. Treatment of Movement Disorders With Focused Ultrasound

    Directory of Open Access Journals (Sweden)

    Paul S Fishman

    2017-05-01

    Full Text Available Although the use of ultrasound as a potential therapeutic modality in the brain has been under study for several decades, relatively few neuroscientists or neurologists are familiar with this technology. Stereotactic brain lesioning had been widely used as a treatment for medically refractory patients with essential tremor (ET, Parkinson disease (PD, and dystonia but has been largely replaced by deep brain stimulation (DBS surgery, with advantages both in safety and efficacy. However, DBS is associated with complications including intracerebral hemorrhage, infection, and hardware malfunction. The occurrence of these complications has spurred interest in less invasive stereotactic brain lesioning methods including magnetic resonance imaging–guided high intensity–focused ultrasound (FUS surgery. Engineering advances now allow sound waves to be targeted noninvasively through the skull to a brain target. High intensities of sonic energy can create a coagulation lesion similar to that of older radiofrequency stereotactic methods, but without opening the skull, recent Food and Drug Administration approval of unilateral thalamotomy for treatment of ET. Clinical studies of stereotactic FUS for aspects of PD are underway. Moderate intensity, pulsed FUS has also demonstrated the potential to safely open the blood-brain barrier for localized delivery of therapeutics including proteins, genes, and cell-based therapy for PD and related disorders. The goal of this review is to provide basic and clinical neuroscientists with a level of understanding to interact with medical physicists, biomedical engineers, and radiologists to accelerate the application of this powerful technology to brain disease

  11. Feasibility Study on MR-Guided High-Intensity Focused Ultrasound Ablation of Sciatic Nerve in a Swine Model: Preliminary Results

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, Elena A., E-mail: kayee@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Medical Physics (United States); Gutta, Narendra Babu, E-mail: gnbabu.aiims@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States); Monette, Sebastien, E-mail: monettes@mskcc.org [The Rockefeller University, Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medical College (United States); Gulati, Amitabh, E-mail: gulatia@mskcc.org; Loh, Jeffrey, E-mail: jeffreyloh@gmail.com [Memorial Sloan Kettering Cancer Center, Department of Anesthesiology-Critical Care (United States); Srimathveeravalli, Govindarajan, E-mail: srimaths@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States); Ezell, Paula C., E-mail: paula.ezell@intusurg.com [The Rockefeller University, Tri-Institutional Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medical College (United States); Erinjeri, Joseph P., E-mail: erinjerj@mskcc.org; Solomon, Stephen B., E-mail: solomons@mskcc.org; Maybody, Majid, E-mail: maybodym@mskcc.org [Memorial Sloan Kettering Cancer Center, Department of Radiology (United States)

    2015-08-15

    IntroductionSpastic patients often seek neurolysis, the permanent destruction of the sciatic nerve, for better pain management. MRI-guided high-intensity focused ultrasound (MRgHIFU) may serve as a noninvasive alternative to the prevailing, more intrusive techniques. This in vivo acute study is aimed at performing sciatic nerve neurolysis using a clinical MRgHIFU system.MethodsThe HIFU ablation of sciatic nerves was performed in swine (n = 5) using a HIFU system integrated with a 3 T MRI scanner. Acute lesions were confirmed using T1-weighted contrast-enhanced (CE) MRI and histopathology using hematoxylin and eosin staining. The animals were euthanized immediately following post-ablation imaging.ResultsReddening and mild thickening of the nerve and pallor of the adjacent muscle were seen in all animals. The HIFU-treated sections of the nerves displayed nuclear pyknosis of Schwann cells, vascular hyperemia, perineural edema, hyalinization of the collagenous stroma of the nerve, myelin sheet swelling, and loss of axons. Ablations were visible on CE MRI. Non-perfused volume of the lesions (5.8–64.6 cc) linearly correlated with estimated lethal thermal dose volume (4.7–34.2 cc). Skin burn adjacent to the largest ablated zone was observed in the first animal. Bilateral treatment time ranged from 55 to 138 min, and preparation time required 2 h on average.ConclusionThe acute pilot study in swine demonstrated the feasibility of a noninvasive neurolysis of the sciatic nerve using a clinical MRgHIFU system. Results revealed that acute HIFU nerve lesions were detectable on CE MRI, gross pathology, and histology.

  12. In vivo characterization of tissue thermal properties of the kidney during local hyperthermia induced by MR-guided high-intensity focused ultrasound.

    Science.gov (United States)

    Cornelis, François; Grenier, Nicolas; Moonen, Chrit T; Quesson, Bruno

    2011-08-01

    The purpose of this study was to evaluate quantitatively in vivo the tissue thermal properties during high-intensity focused ultrasound (HIFU) heating. For this purpose, a total of 52 localized sonications were performed in the kidneys of six pigs with HIFU monitored in real time by volumetric MR thermometry. The kidney perfusion was modified by modulation of the flow in the aorta by insertion of an inflatable angioplasty balloon. The resulting temperature data were analyzed using the bio-heat transfer model in order to validate the model under in vivo conditions and to estimate quantitatively the absorption (α), thermal diffusivity (D) and perfusion (w(b)) of renal tissue. An excellent correspondence was observed between the bio-heat transfer model and the experimental data. The absorption and thermal diffusivity were independent of the flow, with mean values (± standard deviation) of 20.7 ± 5.1 mm(3) K J(-1) and 0.23 ± 0.11 mm(2) s(-1), respectively, whereas the perfusion decreased significantly by 84% (p < 0.01) with arterial flow (mean values of w(b) of 0.06 ± 0.02 and 0.008 ± 0.007 mL(-1) mL s(-1)), as predicted by the model. The quantitative analysis of the volumetric temperature distribution during nondestructive HIFU sonication allows the determination of the thermal parameters, and may therefore improve the quality of the planning of noninvasive therapy with MR-guided HIFU. Copyright © 2010 John Wiley & Sons, Ltd.

  13. Preservation of the endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound ablation of submucosal uterine fibroids

    International Nuclear Information System (INIS)

    Kim, Young-sun; Kim, Tae-Joong; Lee, Jeong-Won; Kim, Byoung-Gie; Lim, Hyo Keun; Rhim, Hyunchul; Jung, Sin-Ho; Ahn, Joong Hyun

    2017-01-01

    To evaluate the integrity of endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of submucosal uterine fibroids based on contrast-enhanced MRI findings, and to identify the risk factors for endometrial impairment. In total, 117 submucosal fibroids (diameter: 5.9 ± 3.0 cm) in 101 women (age: 43.6 ± 4.4 years) treated with MR-HIFU ablation were retrospectively analysed. Endometrial integrity was assessed with contrast-enhanced T1-weighted images at immediate (n = 101), 3-month (n = 62) and 12-month (n = 15) follow-ups. Endometrial impairment was classified into grades 0 (continuous endometrium), 1 (pin-point, full-thickness discontinuity), 2 (between grade 1 and 3), or 3 (full-thickness discontinuity >1 cm). Risk factors were assessed with generalized estimating equation (GEE) analysis. Among 117 fibroids, grades 0, 1, 2 and 3 endometrial impairments were observed at initial examination in 56.4%, 24.8%, 13.7% and 4.3%, respectively. Among 37 fibroid cases of endometrial impairment for which follow-ups were conducted, 30 showed improvements at 3- and/or 12-month follow-up. GEE analysis revealed the degree of endometrial protrusion was significantly associated with severity of endometrial injury (P < 0.0001). After MR-HIFU ablation of submucosal fibroids, endometrial enhancement was preserved intact or minimally impaired in most cases. Impaired endometrium, which is more common after treating endometrially-protruded fibroids, may recover spontaneously. (orig.)

  14. Preservation of the endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound ablation of submucosal uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-sun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); Uterine Fibroid Integrated Management Center, MINT Intervention Hospital, Department of Radiology, Seoul (Korea, Republic of); Kim, Tae-Joong; Lee, Jeong-Won; Kim, Byoung-Gie [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of); Lim, Hyo Keun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); SAIHST, Sungkyunkwan University, Department of Health Sciences and Technology, Seoul (Korea, Republic of); Rhim, Hyunchul [Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Seoul (Korea, Republic of); Jung, Sin-Ho [SAIHST, Sungkyunkwan University, Department of Health Sciences and Technology, Seoul (Korea, Republic of); Samsung Medical Center, Department of Biostatistics and Clinical Epidemiology, Seoul (Korea, Republic of); Ahn, Joong Hyun [Samsung Biomedical Research Institute, Samsung Medical Center, Biostatistics Team, Seoul (Korea, Republic of)

    2017-09-15

    To evaluate the integrity of endometrial enhancement after magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of submucosal uterine fibroids based on contrast-enhanced MRI findings, and to identify the risk factors for endometrial impairment. In total, 117 submucosal fibroids (diameter: 5.9 ± 3.0 cm) in 101 women (age: 43.6 ± 4.4 years) treated with MR-HIFU ablation were retrospectively analysed. Endometrial integrity was assessed with contrast-enhanced T1-weighted images at immediate (n = 101), 3-month (n = 62) and 12-month (n = 15) follow-ups. Endometrial impairment was classified into grades 0 (continuous endometrium), 1 (pin-point, full-thickness discontinuity), 2 (between grade 1 and 3), or 3 (full-thickness discontinuity >1 cm). Risk factors were assessed with generalized estimating equation (GEE) analysis. Among 117 fibroids, grades 0, 1, 2 and 3 endometrial impairments were observed at initial examination in 56.4%, 24.8%, 13.7% and 4.3%, respectively. Among 37 fibroid cases of endometrial impairment for which follow-ups were conducted, 30 showed improvements at 3- and/or 12-month follow-up. GEE analysis revealed the degree of endometrial protrusion was significantly associated with severity of endometrial injury (P < 0.0001). After MR-HIFU ablation of submucosal fibroids, endometrial enhancement was preserved intact or minimally impaired in most cases. Impaired endometrium, which is more common after treating endometrially-protruded fibroids, may recover spontaneously. (orig.)

  15. Synthetic focusing in ultrasound modulated tomography

    KAUST Repository

    Kuchment, Peter; Kunyansky, Leonid

    2010-01-01

    Several hybrid tomographic methods utilizing ultrasound modulation have been introduced lately. Success of these methods hinges on the feasibility of focusing ultrasound waves at an arbitrary point of interest. Such focusing, however, is difficult to achieve in practice. We thus propose a way to avoid the use of focused waves through what we call synthetic focusing, i.e. by reconstructing the would-be response to the focused modulation from the measurements corresponding to realistic unfocused waves. Examples of reconstructions from simulated data are provided. This non-technical paper describes only the general concept, while technical details will appear elsewhere. © 2010 American Institute of Mathematical Sciences.

  16. Synthetic focusing in ultrasound modulated tomography

    KAUST Repository

    Kuchment, Peter

    2010-09-01

    Several hybrid tomographic methods utilizing ultrasound modulation have been introduced lately. Success of these methods hinges on the feasibility of focusing ultrasound waves at an arbitrary point of interest. Such focusing, however, is difficult to achieve in practice. We thus propose a way to avoid the use of focused waves through what we call synthetic focusing, i.e. by reconstructing the would-be response to the focused modulation from the measurements corresponding to realistic unfocused waves. Examples of reconstructions from simulated data are provided. This non-technical paper describes only the general concept, while technical details will appear elsewhere. © 2010 American Institute of Mathematical Sciences.

  17. Perfusion volume correlates, percentage of involution, and clinical efficacy at diverse follow-up survey times after MR-guided focused ultrasound surgery in uterine fibroids: first report in a Mexican mestizo population

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco-Choque, Ana Luz; Fernandez-de Lara, Yeni; Vivas-Bonilla, Ingrid; Romero-Trejo, Cecilia [Medica Sur Clinic and Foundation, Magnetic Resonance Unit, Mexico City (Mexico); Villa, Antonio R. [UNAM, Division de Investigacion, Facultad de Medicina, Mexico City (Mexico); Roldan-Valadez, Ernesto [Medica Sur Clinic and Foundation, Magnetic Resonance Unit, Mexico City (Mexico); Medica Sur Clinic and Foundation, Coordination of Research and Innovation, Magnetic Resonance Unit, Mexico City (Mexico)

    2015-10-15

    To evaluate the clinical efficacy of magnetic resonance-guided focused ultrasound surgery in a Mexican mestizo population. This retrospective study included 159 women (mean age 37 ± 6.4 years, range 22-53 years) from 2008 to 2010. Two hundred sixty-eight symptomatic uterine fibroids were treated using MR-guided focused ultrasound surgery. Parameters included initial perfused volume, final perfused volume, non-perfused volume (NPV), and treated volume ratio (TVR). Follow-up up to 15 months assessed treatment efficacy and symptomatic relief. Non-parametric statistics and the Kaplan-Meier method were performed. T{sub 2}-weighted hypointense fibroids showed a frequency of 93.6 %; isointense and hyperintense fibroids had frequencies of 5.60 and 1.1 %. There was a negative correlation between NPV and age (r = -0.083, p = 0.307) and treatment time (r = -0.253, p = 0.001). Median TVR was 96.0 % in small fibroids and 76.5 % in large fibroids. Involution of 50 % and 80 % was achieved at months 6-7 and month 11, respectively. Relief of symptoms was significant (p < 0.05). Our data show that higher TVR attained immediately post-treatment of MRgFUS favours higher involution percentages at follow-up; however, careful patient selection and use of pretreatment imaging are important components for predicting success using MR-guided focused ultrasound surgery. (orig.)

  18. Effect of biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging, on ultrasound-guided high-intensity focused ultrasound ablation.

    Science.gov (United States)

    Zhao, Wen-Peng; Chen, Jin-Yun; Chen, Wen-Zhi

    2015-02-01

    The aims of this study were to assess the effects of the biological characteristics of different types of uterine fibroids, as assessed with T2-weighted magnetic resonance imaging (MRI), on ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation. Thirty-five patients with 39 symptomatic uterine fibroids who underwent myomectomy or hysterectomy were enrolled. Before surgery, the uterine fibroids were subdivided into hypo-intense, iso-intense, heterogeneous hyper-intense and homogeneous hyper-intense categories based on signal intensity on T2-weighted MRI. Tissue density and moisture content were determined in post-operative samples and normal uterine tissue, the isolated uterine fibroids were subjected to USgHIFU, and the extent of ablation was measured using triphenyltetrazolium chloride. Hematoxylin and eosin staining and sirius red staining were undertaken to investigate the organizational structure of the uterine fibroids. Estrogen and progesterone receptor expression was assayed via immunohistochemical staining. The mean diameter of uterine fibroids was 6.9 ± 2.8 cm. For all uterine fibroids, the average density and moisture content were 10.7 ± 0.7 mg/mL and 75.7 ± 2.4%, respectively; and for the homogeneous hyper-intense fibroids, 10.3 ± 0.5 mg/mL and 76.6 ± 2.3%. The latter subgroup had lower density and higher moisture content compared with the other subgroups. After USgHIFU treatment, the extent of ablation of the hyper-intense fibroids was 102.7 ± 42.1 mm(2), which was significantly less than those of the hypo-intense and heterogeneous hyper-intense fibroids. Hematoxylin and eosin staining and sirius red staining revealed that the homogeneous hyper-intense fibroids had sparse collagen fibers and abundant cells. Immunohistochemistry results revealed that estrogen and progesterone receptors were highly expressed in the homogeneous hyper-intense fibroids. This study revealed that lower density, higher moisture content, sparse collagen

  19. Focus Group Guide

    Science.gov (United States)

    2017-07-01

    home for the arrival of school- aged children. TIP: Do not conduct focus groups in a command conference room in the command group area. Doing so...organizational effectiveness and equal opportunity/equal employment opportunity/fair treatment and sexual assault and response factors (which are listed on the... Sexual Harassment (C) Sex Harassment Retaliation (D) Discrimination - Sex (E) Discrimination - Race (F) Discrimination - Disability (G

  20. Ultrasound guided synovial biopsy of the wrist

    NARCIS (Netherlands)

    van Vugt, R. M.; van Dalen, A.; Bijlsma, J. W.

    1997-01-01

    Seven patients (4 female and 3 male, mean age 46) with arthritis of the wrist (n = 7) without known etiology were evaluated. High-definition ultrasound equipment was used for localization of synovial hypertrophy, suitable for ultrasound guided biopsy without risk. A 18-gauge diameter Tru-cut biopsy

  1. Manipulation of Microbubble Clusters Using Focused Ultrasound

    Science.gov (United States)

    Matsuzaki, Hironobu; Osaki, Taichi; Kawaguchi, Kei; Unga, Johan; Ichiyanagi, Mitsuhisa; Azuma, Takashi; Suzuki, Ryo; Maruyama, Kazuo; Takagi, Shu

    2017-11-01

    In recent years, microbubbles (MBs) are expected to be utilized for the ultrasound drug delivery system (DDS). For the MB-DDS, it is important to establish a method of controlling bubbles and bubble clusters using ultrasound field. The objective of this study is to clarify behaviors of bubble clusters with various physical conditions. MBs in the ultrasound field are subjected to the primary Bjerknes force. The force traps MBs at the focal region of the focused ultrasound field. The trapped MBs form a bubble cluster at the region. A bubble cluster continues growing with absorbing surrounding bubbles until it reaches a maximum size beyond which it disappears from the focal region. In the present study, two kinds of MBs are used for the experiment. One is Sonazoid with average diameter of 2.6 um and resonant frequency of 5 MHz. The other is developed by Teikyo Univ., with average diameter of 1.5 um and presumed resonant frequency of 4 MHz. The bubble cluster's behaviors are analyzed using the high-speed camera. Sonazoid clusters have larger critical size than the other in every frequency, and its cluster size is inversely proportional to the ultrasound frequency, while Teikyo-bubble clusters have different tendency. These results are discussed in the presentation.

  2. [Endoscopic ultrasound guided rendezvous for biliary drainage].

    Science.gov (United States)

    Knudsen, Marie Høxbro; Vilmann, Peter; Hassan, Hazem; Karstensen, John Gésdal

    2015-04-27

    Endoscopic retrograde cholangiography (ERCP) is currently standard treatment for biliary drainage. Endoscopic ultrasound guided rendezvous (EUS-RV) is a novel method to overcome an unsuccessful biliary drainage procedure. Under endoscopic ultrasound guidance a guidewire is passed via a needle from the stomach or duodenum to the common bile duct and from there on to the duodenum enabling ERCP. With a relatively high rate of success EUS-RV should be considered as an alternative to biliary drainage and surgical intervention.

  3. Magnetic Resonance-Guided High-Intensity Focused Ultrasound (MRgHIFU) for Treatment of Symptomatic Uterine Fibroids: An Economic Analysis

    Science.gov (United States)

    Babashov, V; Palimaka, S; Blackhouse, G; O'Reilly, D

    2015-01-01

    Background Uterine fibroids, or leiomyomas, are the most common benign tumours in women of childbearing age. Some women experience symptoms (e.g., heavy bleeding) that require aggressive forms of treatment such as uterine artery embolization (UAE), myomectomy, magnetic resonance-guided high-intensity focused ultrasound (MRgHIFU), and even hysterectomy. It is important to note that hysterectomy is not appropriate for women who desire future childbearing. Objectives The objective of this analysis was to evaluate the cost-effectiveness and budgetary impact of implementing MRgHIFU as a treatment option for symptomatic uterine fibroids in premenopausal women for whom drugs have been ineffective. Review Methods We performed an original cost-effectiveness analysis to assess the long-term costs and effects of MRgHIFU compared with hysterectomy, myomectomy, and UAE as a strategy for treating symptomatic uterine fibroids in premenopausal women aged 40 to 51 years. We explored a number of scenarios, e.g., comparing MRgHIFU with uterine-preserving procedures only, considering MRgHIFU-eligible patients only, and eliminating UAE as a treatment option. In addition, we performed a one-year budget impact analysis, using data from Ontario administrative sources. Four scenarios were explored in the budgetary impact analysis: MRgHIFU funded at 2 centres MRgHIFU funded at 2 centres and replacing only uterine-preserving procedures MRgHIFU funded at 6 centres MRgHIFU funded at 6 centres and replacing only uterine-preserving procedures Analyses were conducted from the Ontario public payer perspective. Results The base case determined that the uterine artery embolization (UAE) treatment strategy was the cost-effective option at commonly accepted willingness-to-pay values. Compared with hysterectomy, UAE was calculated as having an incremental cost-effectiveness ratio (ICER) of $46,480 per quality-adjusted life-year (QALY) gained. The MRgHIFU strategy was extendedly dominated by a

  4. Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid An ... Aspiration Biopsy of the Thyroid? What is Ultrasound-Guided Fine Needle Aspiration Biopsy of the Thyroid? During ...

  5. Guiding tissue regeneration with ultrasound in vitro and in vivo

    Science.gov (United States)

    Dalecki, Diane; Comeau, Eric S.; Raeman, Carol H.; Child, Sally Z.; Hobbs, Laura; Hocking, Denise C.

    2015-05-01

    Developing new technologies that enable the repair or replacement of injured or diseased tissues is a major focus of regenerative medicine. This paper will discuss three ultrasound technologies under development in our laboratories to guide tissue regeneration both in vitro and in vivo. A critical obstacle in tissue engineering is the need for rapid and effective tissue vascularization strategies. To address this challenge, we are developing acoustic patterning techniques for microvascular tissue engineering. Acoustic radiation forces associated with ultrasound standing wave fields provide a rapid, non-invasive approach to spatially pattern cells in three dimensions without affecting cell viability. Acoustic patterning of endothelial cells leads to the rapid formation of microvascular networks throughout the volumes of three-dimensional hydrogels, and the morphology of the resultant microvessel networks can be controlled by design of the ultrasound field. A second technology under development uses ultrasound to noninvasively control the microstructure of collagen fibers within engineered tissues. The microstructure of extracellular matrix proteins provides signals that direct cell functions critical to tissue regeneration. Thus, controlling collagen microfiber structure with ultrasound provides a noninvasive approach to regulate the mechanical properties of biomaterials and control cellular responses. The third technology employs therapeutic ultrasound to enhance the healing of chronic wounds. Recent studies demonstrate increased granulation tissue thickness and collagen deposition in murine dermal wounds exposed to pulsed ultrasound. In summary, ultrasound technologies offer noninvasive approaches to control cell behaviors and extracellular matrix organization and thus hold great promise to advance tissue regeneration in vitro and in vivo.

  6. Ultrasound- and MRI-Guided Prostate Biopsy

    Science.gov (United States)

    ... assistance of a nurse and an MR imaging technologist. As with the ultrasound procedure, you may receive antibiotics, sedatives and pain medication before the biopsy. The MRI-guided procedure may use contrast ... A nurse or technologist will insert an intravenous (IV) catheter into a ...

  7. Ultrasound-guided forceps for pleural biopsy

    Directory of Open Access Journals (Sweden)

    Gamal Agmy

    2014-04-01

    Clinical implications: Ultrasound-guided forceps for pleural biopsy can overcome many of the limitations of the conventional needle biopsy procedures, provides multiple biopsy specimens of the parietal pleura that are inaccessible to the biopsy needle, and can be carried out easily and safely even in sick and obese patients. The diagnostic yield is nearly similar to thoracoscopy.

  8. Ultrasound guided local steroid injection versus extracorporeal ...

    African Journals Online (AJOL)

    Nayera Saber

    2011-12-17

    Dec 17, 2011 ... Results: There was a statistically significant reduction in plantar fascia .... Several previous studies evaluate the effects of either local ... The choice of ultrasound guided technique of steroid injection was related to the accuracy of application and supe- ..... chronic proximal plantar fasciitis: a meta analysis.

  9. MRI monitoring of focused ultrasound sonications near metallic hardware.

    Science.gov (United States)

    Weber, Hans; Ghanouni, Pejman; Pascal-Tenorio, Aurea; Pauly, Kim Butts; Hargreaves, Brian A

    2018-07-01

    To explore the temperature-induced signal change in two-dimensional multi-spectral imaging (2DMSI) for fast thermometry near metallic hardware to enable MR-guided focused ultrasound surgery (MRgFUS) in patients with implanted metallic hardware. 2DMSI was optimized for temperature sensitivity and applied to monitor focus ultrasound surgery (FUS) sonications near metallic hardware in phantoms and ex vivo porcine muscle tissue. Further, we evaluated its temperature sensitivity for in vivo muscle in patients without metallic hardware. In addition, we performed a comparison of temperature sensitivity between 2DMSI and conventional proton-resonance-frequency-shift (PRFS) thermometry at different distances from metal devices and different signal-to-noise ratios (SNR). 2DMSI thermometry enabled visualization of short ultrasound sonications near metallic hardware. Calibration using in vivo muscle yielded a constant temperature sensitivity for temperatures below 43 °C. For an off-resonance coverage of ± 6 kHz, we achieved a temperature sensitivity of 1.45%/K, resulting in a minimum detectable temperature change of ∼2.5 K for an SNR of 100 with a temporal resolution of 6 s per frame. The proposed 2DMSI thermometry has the potential to allow MR-guided FUS treatments of patients with metallic hardware and therefore expand its reach to a larger patient population. Magn Reson Med 80:259-271, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  10. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    International Nuclear Information System (INIS)

    Ellens, N; Farahani, K

    2015-01-01

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  11. SU-E-J-03: Characterization of the Precision and Accuracy of a New, Preclinical, MRI-Guided Focused Ultrasound System for Image-Guided Interventions in Small-Bore, High-Field Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, N [Johns Hopkins University, Baltimore, Maryland (United States); Farahani, K [National Cancer Institute, Bethesda, MD (United States)

    2015-06-15

    Purpose: MRI-guided focused ultrasound (MRgFUS) has many potential and realized applications including controlled heating and localized drug delivery. The development of many of these applications requires extensive preclinical work, much of it in small animal models. The goal of this study is to characterize the spatial targeting accuracy and reproducibility of a preclinical high field MRgFUS system for thermal ablation and drug delivery applications. Methods: The RK300 (FUS Instruments, Toronto, Canada) is a motorized, 2-axis FUS positioning system suitable for small bore (72 mm), high-field MRI systems. The accuracy of the system was assessed in three ways. First, the precision of the system was assessed by sonicating regular grids of 5 mm squares on polystyrene plates and comparing the resulting focal dimples to the intended pattern, thereby assessing the reproducibility and precision of the motion control alone. Second, the targeting accuracy was assessed by imaging a polystyrene plate with randomly drilled holes and replicating the hole pattern by sonicating the observed hole locations on intact polystyrene plates and comparing the results. Third, the practicallyrealizable accuracy and precision were assessed by comparing the locations of transcranial, FUS-induced blood-brain-barrier disruption (BBBD) (observed through Gadolinium enhancement) to the intended targets in a retrospective analysis of animals sonicated for other experiments. Results: The evenly-spaced grids indicated that the precision was 0.11 +/− 0.05 mm. When image-guidance was included by targeting random locations, the accuracy was 0.5 +/− 0.2 mm. The effective accuracy in the four rodent brains assessed was 0.8 +/− 0.6 mm. In all cases, the error appeared normally distributed (p<0.05) in both orthogonal axes, though the left/right error was systematically greater than the superior/inferior error. Conclusions: The targeting accuracy of this device is sub-millimeter, suitable for many

  12. Spatial filters for focusing ultrasound images

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gori, Paola

    2001-01-01

    , but the approach always yields point spread functions better or equal to a traditional dynamically focused image. Finally, the process was applied to in-vivo clinical images of the liver and right kidney from a 28 years old male. The data was obtained with a single element transducer focused at 100 mm....... A new method for making spatial matched filter focusing of RF ultrasound data is proposed based on the spatial impulse response description of the imaging. The response from a scatterer at any given point in space relative to the transducer can be calculated, and this gives the spatial matched filter...... for synthetic aperture imaging for single element transducers. It is evaluated using the Field II program. Data from a single 3 MHz transducer focused at a distance of 80 mm is processed. Far from the transducer focal region, the processing greatly improves the image resolution: the lateral slice...

  13. Outcomes of ultrasound guided renal mass biopsies.

    Science.gov (United States)

    Sutherland, Edward L; Choromanska, Agnieszka; Al-Katib, Sayf; Coffey, Mary

    2018-06-01

    The purpose of this study was to evaluate the rate of nondiagnostic ultrasound-guided renal mass biopsies (RMBs) at our institution and to determine what patient, procedural, and focal renal mass (FRM) factors were associated with nondiagnostic ultrasound-guided RMBs. Eighty-two ultrasound-guided renal mass biopsies performed between January 2014 and October 2016 were included in our study. Biopsy outcomes (diagnostic vs. nondiagnostic) and patient, procedural, and FRM characteristics were retrospectively reviewed and recorded. Univariate statistical analyses were performed to identify biopsy characteristics that were indicative of nondiagnostic biopsy. Ultrasound-guided RMBs were diagnostic in 70 out of 82 cases (85%) and non-diagnostic in 12 cases (15%). Among the diagnostic biopsies, 54 (77%) were malignant cases, 94% of which were renal cell carcinoma (RCC). Of the 12 nondiagnostic cases, the final diagnosis was RCC in 4 cases and angiomyolipoma in one case; seven of the nondiagnostic cases were lost to follow-up. A weak association (p = 0.04) was found between the number of needle passes and the biopsy outcome. None of the remaining collected RMB characteristics showed a significant correlation with a diagnostic or nondiagnostic RMB. Six patients (7%) experienced complications. Ultrasound-guided renal mass biopsy is a safe and effective method for the diagnosis of renal masses with a low rate of nondiagnostic outcomes. A nondiagnostic biopsy should not be treated as a surrogate for a diagnosis since a significant number of patients with nondiagnostic biopsies have subsequently been shown to have renal malignancies. Repeat biopsy should be considered in such cases.

  14. Ultrasound-guided drug delivery in cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chowdhury, Sayan Mullick; Lee, Tae Hwa; Willmann, Jugen K. [Dept. of Radiology, Stanford University School of Medicine, Stanford (United States)

    2017-07-15

    Recent advancements in ultrasound and microbubble (USMB) mediated drug delivery technology has shown that this approach can improve spatially confined delivery of drugs and genes to target tissues while reducing systemic dose and toxicity. The mechanism behind enhanced delivery of therapeutics is sonoporation, the formation of openings in the vasculature, induced by ultrasound-triggered oscillations and destruction of microbubbles. In this review, progress and challenges of USMB mediated drug delivery are summarized, with special focus on cancer therapy.

  15. Ultrasound-guided drug delivery in cancer

    Directory of Open Access Journals (Sweden)

    Sayan Mullick Chowdhury

    2017-07-01

    Full Text Available Recent advancements in ultrasound and microbubble (USMB mediated drug delivery technology has shown that this approach can improve spatially confined delivery of drugs and genes to target tissues while reducing systemic dose and toxicity. The mechanism behind enhanced delivery of therapeutics is sonoporation, the formation of openings in the vasculature, induced by ultrasound-triggered oscillations and destruction of microbubbles. In this review, progress and challenges of USMB mediated drug delivery are summarized, with special focus on cancer therapy.

  16. Intensity dependence of focused ultrasound lesion position

    Science.gov (United States)

    Meaney, Paul M.; Cahill, Mark D.; ter Haar, Gail R.

    1998-04-01

    Knowledge of the spatial distribution of intensity loss from an ultrasonic beam is critical to predicting lesion formation in focused ultrasound surgery. To date most models have used linear propagation models to predict the intensity profiles needed to compute the temporally varying temperature distributions. These can be used to compute thermal dose contours that can in turn be used to predict the extent of thermal damage. However, these simulations fail to adequately describe the abnormal lesion formation behavior observed for in vitro experiments in cases where the transducer drive levels are varied over a wide range. For these experiments, the extent of thermal damage has been observed to move significantly closer to the transducer with increasing transducer drive levels than would be predicted using linear propagation models. The simulations described herein, utilize the KZK (Khokhlov-Zabolotskaya-Kuznetsov) nonlinear propagation model with the parabolic approximation for highly focused ultrasound waves, to demonstrate that the positions of the peak intensity and the lesion do indeed move closer to the transducer. This illustrates that for accurate modeling of heating during FUS, nonlinear effects must be considered.

  17. Ultrasound-guided sacroiliac joint injection technique.

    LENUS (Irish Health Repository)

    Harmon, Dominic

    2008-07-01

    We describe a case report and technique for using a portable ultrasound scanner and a curvilinear transducer (4-5MHz) (SonoSite Micromaxx SonoSite, Inc. 21919 30th Drive SE Bothwell W. A.) to guide sacroiliac joint (SIJ) injection. A 42-year-old male presented with chronic lower back pain centered on his left SIJ. His pain averaged 7 out of 10 (numerical rating scale). For the ultrasound-guided SIJ injection the patient was placed in the prone position. The ultrasound transducer was oriented in a transverse orientation at the level of the sacral hiatus. Here the sacral cornuae were identified. Moving the transducer laterally from here, the lateral edge of the sacrum was identified. This bony edge was followed in a cephalad direction with the transducer maintained in a transverse orientation. A second bony contour, the ileum, was identified. The cleft between both bony contours represented the sacroiliac joint. This was found at 4.5 cm depth. Real-time imaging was used to direct a 22G spinal needle into the SIJ, where solution was injected under direct vision. The patient\\'s pain intensity decreased to a 2 out of 10 (numerical rating scale). Function improved and the patient was able to return to work. These improvements were maintained at 16 weeks. Ultrasound guidance does not expose patients and personnel to radiation and is readily accessible. Ultrasound-guided SIJ injections may have particular applications in the management of chronic lower back pain in certain clinical scenarios (e.g. pregnancy). Future studies to demonstrate efficacy and reproducibility are needed.

  18. Ultrasound-guided removal of Implanon devices.

    LENUS (Irish Health Repository)

    Persaud, T

    2008-11-01

    Our study has shown that ultrasound-guided localisation and removal of Implanon rods is safe, practical and highly successful. Over a 4-year period, 119 patients had successful, uncomplicated removal of their subdermal devices.The technique is particularly useful for removal of the device when it is not palpable or when an attempt at removal of a palpable device has not been successful.

  19. Externally Delivered Focused Ultrasound for Renal Denervation.

    Science.gov (United States)

    Neuzil, Petr; Ormiston, John; Brinton, Todd J; Starek, Zdenek; Esler, Murray; Dawood, Omar; Anderson, Thomas L; Gertner, Michael; Whitbourne, Rob; Schmieder, Roland E

    2016-06-27

    The aim of this study was to assess clinical safety and efficacy outcomes of renal denervation executed by an externally delivered, completely noninvasive focused therapeutic ultrasound device. Renal denervation has emerged as a potential treatment approach for resistant hypertension. Sixty-nine subjects received renal denervation with externally delivered focused ultrasound via the Kona Medical Surround Sound System. This approach was investigated across 3 consecutive studies to optimize targeting, tracking, and dosing. In the third study, treatments were performed in a completely noninvasive way using duplex ultrasound image guidance to target the therapy. Short- and long-term safety and efficacy were evaluated through use of clinical assessments, magnetic resonance imaging scans prior to and 3 and 24 weeks after renal denervation, and, in cases in which a targeting catheter was used to facilitate targeting, fluoroscopic angiography with contrast. All patients tolerated renal denervation using externally delivered focused ultrasound. Office blood pressure (BP) decreased by 24.6 ± 27.6/9.0 ± 15.0 mm Hg (from baseline BP of 180.0 ± 18.5/97.7 ± 13.7 mm Hg) in 69 patients after 6 months and 23.8 ± 24.1/10.3 ± 13.1 mm Hg in 64 patients with complete 1-year follow-up. The response rate (BP decrease >10 mm Hg) was 75% after 6 months and 77% after 1 year. The most common adverse event was post-treatment back pain, which was reported in 32 of 69 patients and resolved within 72 h in most cases. No intervention-related adverse events involving motor or sensory deficits were reported. Renal function was not altered, and vascular safety was established by magnetic resonance imaging (all patients), fluoroscopic angiography (n = 48), and optical coherence tomography (n = 5). Using externally delivered focused ultrasound and noninvasive duplex ultrasound, image-guided targeting was associated with substantial BP reduction without any major safety signals. Further

  20. Endoscopic Ultrasound-Guided Biliary Drainage

    International Nuclear Information System (INIS)

    Artifon, Everson L.A.; Ferreira, Fla'vio C.; Sakai, Paulo

    2012-01-01

    To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

  1. Endoscopic Ultrasound-Guided Biliary Drainage

    Energy Technology Data Exchange (ETDEWEB)

    Artifon, Everson L.A.; Ferreira, Fla& #x27; vio C.; Sakai, Paulo [University of Saeo Paulo, Saeo Paulo (Brazil)

    2012-02-15

    To demonstrate a comprehensive review of published articles regarding endoscopic ultrasound (EUS)-guided biliary drainage. Review of studies regarding EUS-guided biliary drainage including case reports, case series and previous reviews. EUS-guided hepaticogastrostomy, coledochoduodenostomy and choledoantrostomy are advanced biliary and pancreatic endoscopy procedures, and together make up the echo-guided biliary drainage. Hepaticogastrostomy is indicated in cases of hilar obstruction, while the procedure of choice is the coledochoduodenostomy or choledochoantrostomy in distal lesions. Both procedures must be performed only after unsuccessful ERCPs. The indication of these procedures must be made under a multidisciplinary view while sharing information with the patient or legal guardian. Hepaticogastrostomy and coledochoduodenostomy or choledochoantrostomy are feasible when performed by endoscopists with expertise in biliopancreatic endoscopy. Advanced echo-endoscopy should currently be performed under a rigorous protocol in educational institutions.

  2. Existing Evidence on Ultrasound-Guided Injections in Sports Medicine.

    Science.gov (United States)

    Daniels, Eldra W; Cole, David; Jacobs, Bret; Phillips, Shawn F

    2018-02-01

    Office-based ultrasonography has become increasingly available in many settings, and its use to guide joint and soft tissue injections has increased. Numerous studies have been conducted to evaluate the use of ultrasound-guided injections over traditional landmark-guided injections, with a rapid growth in the literature over the past few years. A comprehensive review of the literature was conducted to demonstrate increased accuracy of ultrasound-guided injections regardless of anatomic location. In the upper extremity, ultrasound-guided injections have been shown to provide superior benefit to landmark-guided injections at the glenohumeral joint, the subacromial space, the biceps tendon sheath, and the joints of the hand and wrist. Ultrasound-guided injections of the acromioclavicular and the elbow joints have not been shown to be more efficacious. In the lower extremity, ultrasound-guided injections at the knee, ankle, and foot have superior efficacy to landmark-guided injections. Conclusive evidence is not available regarding improved efficacy of ultrasound-guided injections of the hip, although landmark-guided injection is performed less commonly at the hip joint. Ultrasound-guided injections are overall more accurate than landmark-guided injections. While current studies indicate that ultrasound guidance improves efficacy and cost-effectiveness of many injections, these studies are limited and more research is needed.

  3. WE-G-12A-01: High Intensity Focused Ultrasound Surgery and Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Farahani, K [National Cancer Institute, Rockville, MD (United States); O' Neill, B [The Methodist Hospital Research Institute, Houston, TX (United States)

    2014-06-15

    More and more emphasis is being made on alternatives to invasive surgery and the use of ionizing radiation to treat various diseases including cancer. Novel screening, diagnosis, treatment and monitoring of response to treatment are also hot areas of research and new clinical technologies. Ultrasound(US) has gained traction in all of the aforementioned areas of focus. Especially with recent advances in the use of ultrasound to noninvasively treat various diseases/organ systems. This session will focus on covering MR-guided focused ultrasound and the state of the art clinical applications, and the second speaker will survey the more cutting edge technologies e.g. Focused Ultrasound (FUS) mediated drug delivery, principles of cavitation and US guided FUS. Learning Objectives: Fundamental physics and physical limitations of US interaction with tissue and nanoparticles The alteration of tissue transport using focused ultrasound US control of nanoparticle drug carriers for targeted release The basic principles of MRI-guided focused ultrasound (MRgFUS) surgery and therapy the current state of the art clinical applications of MRgFUS requirements for quality assurance and treatment planning.

  4. Impact of Focused Ultrasound-enhanced Drug Delivery on Survival in Rats with Glioma

    Science.gov (United States)

    Treat, Lisa Hsu; Zhang, Yongzhi; McDannold, Nathan; Hynynen, Kullervo

    2009-04-01

    Malignancies of the brain remain difficult to treat with chemotherapy because the selective permeability of the blood-brain barrier (BBB) blocks many potent agents from reaching their target. Previous studies have illustrated the feasibility of drug and antibody delivery across the BBB using MRI-guided focused ultrasound. In this study, we investigated the impact of focused ultrasound-enhanced delivery of doxorubicin on survival in rats with aggressive glioma. Sprague-Dawley rats were implanted with 9 L gliosarcoma cells in the brain. Eight days after implantation, each rat received one of the following: (1) no treatment (control), (2) a single treatment with microbubble-enhanced MRI-guided focused ultrasound (FUS only), (3) a single treatment with i.v. liposomal doxorubicin (DOX only), or (4) a single treatment with microbubble-enhanced MRI-guided focused ultrasound and concurrent i.v. injections of liposomal doxorubicin (FUS+DOX). The survival time from implantation to death or euthanasia was recorded. We observed a modest but significant increase in median survival time in rats treated with combined MRI-guided focused ultrasound chemotherapy, compared to chemotherapy alone (p0.10). Our study demonstrates for the first time a therapeutic benefit achieved with ultrasound-enhanced drug delivery across the blood-brain barrier. This confirmation of efficacy in an in vivo tumor model indicates that targeted drug delivery using MRI-guided focused ultrasound has the potential to have a major impact on the treatment of patients with brain tumors and other neurological disorders.

  5. Ultrasound guided pleural biopsy in undiagnosed exudative pleural effusion patients

    Directory of Open Access Journals (Sweden)

    Adel S. Ahmed

    2016-04-01

    In conclusion: Thoracic ultrasound (TUS guided pleural biopsy had a diagnostic yield which was slightly lower but comparable to both CT guided pleural biopsy and medical thoracoscopic pleural biopsy (MT.

  6. Trans-abdominal ultrasound evaluation of high-intensity focused ultrasound treatment of uterine leiomyoma

    International Nuclear Information System (INIS)

    Miao Wei; Huang Jin; Wang Junhua; Wang Yuling

    2010-01-01

    Objective: To determine the value of dynamic trans-abdominal ultrasound after high-intensity focused ultrasound (HIFU) treatment of uterine leiomyomas. Methods: The trans-abdominal ultrasound images of 63 patients before and after HIFU treatment of uterine leiomyomas were compared. Results: The volume and blood flow of leiomyomas were reduced after the HIFU treatment. Conclusion: Trans-abdominal ultrasound is a valuable method for evaluating the results of HIFU treatment of uterine leiomyomas. (authors)

  7. High intensity focused ultrasound treatment of small renal masses: Clinical effectiveness and technological advances

    Science.gov (United States)

    Nabi, G.; Goodman, C.; Melzer, A.

    2010-01-01

    The review summarises the technological advances in the application of high-intensity focused ultrasound for small renal masses presumed to be cancer including the systematic review of its clinical application. Current progress in the area of magnetic resonance image guided ultrasound ablation is also appraised. Specifically, organ tracking and real time monitoring of temperature changes during the treatment are discussed. Finally, areas of future research interest are outlined. PMID:21116349

  8. High intensity focused ultrasound treatment of small renal masses: Clinical effectiveness and technological advances

    OpenAIRE

    Nabi, G.; Goodman, C.; Melzer, A.

    2010-01-01

    The review summarises the technological advances in the application of high-intensity focused ultrasound for small renal masses presumed to be cancer including the systematic review of its clinical application. Current progress in the area of magnetic resonance image guided ultrasound ablation is also appraised. Specifically, organ tracking and real time monitoring of temperature changes during the treatment are discussed. Finally, areas of future research interest are outlined.

  9. Laser-nucleated acoustic cavitation in focused ultrasound.

    Science.gov (United States)

    Gerold, Bjoern; Kotopoulis, Spiros; McDougall, Craig; McGloin, David; Postema, Michiel; Prentice, Paul

    2011-04-01

    Acoustic cavitation can occur in therapeutic applications of high-amplitude focused ultrasound. Studying acoustic cavitation has been challenging, because the onset of nucleation is unpredictable. We hypothesized that acoustic cavitation can be forced to occur at a specific location using a laser to nucleate a microcavity in a pre-established ultrasound field. In this paper we describe a scientific instrument that is dedicated to this outcome, combining a focused ultrasound transducer with a pulsed laser. We present high-speed photographic observations of laser-induced cavitation and laser-nucleated acoustic cavitation, at frame rates of 0.5×10(6) frames per second, from laser pulses of energy above and below the optical breakdown threshold, respectively. Acoustic recordings demonstrated inertial cavitation can be controllably introduced to the ultrasound focus. This technique will contribute to the understanding of cavitation evolution in focused ultrasound including for potential therapeutic applications. © 2011 American Institute of Physics

  10. Ultrasound guided electrochemotherapy for the treatment of a clear ...

    African Journals Online (AJOL)

    Ultrasound guided biopsy yielded a diagnosis of clear cell thymoma upon histopathology. After complete staging procedures, the owner elected to treat the cat with electrochemotherapy (ECT) using systemic bleomycin. Two sessions of ultrasound guided ECT were performed at two week intervals with trains of biphasic ...

  11. WE-EF-BRA-12: Magnetic Resonance- Guided High-Intensity Focused Ultrasound for Localized Ablation of Head and Neck Tissue Structures: A Feasibility Study in An Animal Model

    International Nuclear Information System (INIS)

    Partanen, A; Ellens, N; Noureldine, S; Tufano, R; Burdette, E; Farahani, K

    2015-01-01

    Purpose: High-intensity focused ultrasound (HIFU) ablation is feasible in the head and neck [1]. This study aims to expand upon these findings to assess the feasibility of treatment planning and monitoring via magnetic resonance imaging (MRI) guidance using a clinical MR-guided HIFU platform. Methods: Two 31 kg pigs were anaesthetized, shaved, and positioned prone on the HIFU table (Sonalleve, Philips Healthcare, Vantaa, Finland). The necks were acoustically coupled to the integrated transducer using gel pads and degassed water. MR imaging verified acoustic coupling and facilitated target selection in the thyroid and thymus. Targets were thermally ablated with 130–200 W of acoustic power over a period of 16 s at a frequency of 1.2 MHz while being monitored through real-time, multi-planar MR-thermometry. Contrast-enhanced MR imaging was used to assess treatment efficacy. Post-treatment, animals were euthanized and sonicated tissues were harvested for histology assessment. Results: MR-thermometry, post-contrast-imaging, and gross pathology demonstrated that the system was capable of causing localized thermal ablation in both the thyroid and the thymus without damaging the aerodigestive tract. In one animal, superficial bruising was observed in the ultrasound beam path. Otherwise, there were no adverse events. Analysis of the tissue histology found regions of damage consistent with acute thermal injury at the targeted locations. Conclusion: It is feasible to use a clinical MR-guided HIFU platform for extracorporeal ablation of porcine head and neck tissues. MR guidance and thermometry are sufficient to target and monitor treatment in the thyroid region, despite the presence of the inhomogeneous aerodigestive tract. Further study is necessary to assess efficacy and survival using a tumor model, and to examine what modifications should be made to the transducer positioning system and associated patient positioning aids to adapt it for clinical head and neck targets

  12. Scaled signal intensity of uterine fibroids based on T2-weighted MR images: a potential objective method to determine the suitability for magnetic resonance-guided focused ultrasound surgery of uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun [CHA University, Comprehensive Gynecologic Cancer Center, CHA Bundang Medical Center, Gyunggi-do (Korea, Republic of); Yoon, Sang-Wook [CHA University, Department of Diagnostic Radiology, CHA Bundang Medical Center, Sungnam-si, Gyunggi-do (Korea, Republic of); Sokolov, Amit [InSightec Ltd., Haifa (Israel)

    2015-12-15

    Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a non-invasive method to treat uterine fibroids. To help determine the patient suitability for MRgFUS, we propose a new objective measure: the scaled signal intensity (SSI) of uterine fibroids in T2 weighted MR images (T2WI). Forty three uterine fibroids in 40 premenopausal women were included in this retrospective study. SSI of each fibroid was measured from the screening T2WI by standardizing its mean signal intensity to a 0-100 scale, using reference intensities of rectus abdominis muscle (0) and subcutaneous fat (100). Correlation between the SSI and the non-perfused volume (NPV) ratio (a measure for treatment success) was calculated. Pre-treatment SSI showed a significant inverse-correlation with post treatment NPV ratio (p < 0.05). When dichotomizing NPV ratio at 45 %, the optimal cut off value of the SSI was found to be 16.0. A fibroid with SSI value 16.0 or less can be expected to have optimal responses. The SSI of uterine fibroids in T2WI can be suggested as an objective parameter to help in patient selection for MRgFUS. (orig.)

  13. Scaled signal intensity of uterine fibroids based on T2-weighted MR images: a potential objective method to determine the suitability for magnetic resonance-guided focused ultrasound surgery of uterine fibroids.

    Science.gov (United States)

    Park, Hyun; Yoon, Sang-Wook; Sokolov, Amit

    2015-12-01

    Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) is a non-invasive method to treat uterine fibroids. To help determine the patient suitability for MRgFUS, we propose a new objective measure: the scaled signal intensity (SSI) of uterine fibroids in T2 weighted MR images (T2WI). Forty three uterine fibroids in 40 premenopausal women were included in this retrospective study. SSI of each fibroid was measured from the screening T2WI by standardizing its mean signal intensity to a 0-100 scale, using reference intensities of rectus abdominis muscle (0) and subcutaneous fat (100). Correlation between the SSI and the non-perfused volume (NPV) ratio (a measure for treatment success) was calculated. Pre-treatment SSI showed a significant inverse-correlation with post treatment NPV ratio (p < 0.05). When dichotomizing NPV ratio at 45 %, the optimal cut off value of the SSI was found to be 16.0. A fibroid with SSI value 16.0 or less can be expected to have optimal responses. The SSI of uterine fibroids in T2WI can be suggested as an objective parameter to help in patient selection for MRgFUS. • Signal intensity of fibroid in MR images predicts treatment response to MRgFUS. • Signal intensity is standardized into scaled form using adjacent tissues as references. • Fibroids with SSI less than 16.0 are expected to have optimal responses.

  14. Percutaneous antegrade pyelgraphy guided by ultrasound

    International Nuclear Information System (INIS)

    Kim, Jin Gyoo; Chung, Chun Phil; Lee, Suk Hong; Sol, Chang Hyo; Kim, Byung Soo

    1985-01-01

    The authors performed percutaneous antegrade pyelography guided by ultrasound on 33 patients, from June 1982 to October 1984, at the Department of Radiology, Busan National University Hospital. The results obtained were as follows: 1. Of the 31 cases, 17 cases (51.5%) were female and 16 cases (48.5%) were male, and age distribution was nearly even, but most prevalent age group was third decade. 2. Comparing intravenous pyelographic findings with ultrasonographic findings, pyelographically nonvisualized kidney 15 cases (45.5%) were hydronephrosis 12 cases, multiple cysts 2 cases, and intrarenal cystic mass 1 case, ultrasonographically. Pyelographically hydronephrosis 9 cases (27.3%) were all hydronephrosis, ultrasonographically. Intrarenal mass 5 cases (15.2%) were all intrarenal cystic mass, NVK with air kidney 1 case (3.0%) was air in perirenal space, partial NVK 1 case (3.0%) was perirenal fluid, suprarenal mass 1 case (3.0%) was suprarenal intrarenal and huge perirenal cystic masses, ultrasonographically. 3. On technical reliability of antegrade pyelography under ultrasound guide, 31 cases (93.9%) could be done fluid aspiration and visualization, and 2 cases (6.1%) could be only done fluid aspiration but failed visualization. 31 successful cases were visualization of collecting systems 23 cases, visualization of cyst 6 case, and visualization of perirenal space 2 cases. 2 partical successful cases were perirenal injection 1 case and parenchymal injection 1 case. 4. On fluid aspiration, 22 cases (66.7%) were clear, but 11 cases (33.3%) were not clear, which were pus 7 cases, turbid urine 2 cases, bloody urine 1 case, and bloody pus and air 1 case. 5. Comparing ultrasonographic findings with antegrade pyelographic findings, ultrasonographiclly hydronephrosis 21 cases revealed obstruction in 16 cases, antegrade pyelographicaaly, which were consisted of ureteral stricture 14 case, ureteral stone 1 case, and ureteral mass 1 case, non-obstruction in 4 cases, which

  15. Ultrasound-guided botulinum toxin injections

    Directory of Open Access Journals (Sweden)

    S. E. Khatkova

    2016-01-01

    Full Text Available One of the key conditions for achieving the desirable result during botulinum toxin therapy for muscular dystonia, spasticity, and other diseases accompanied by spasm, pain, and autonomic dysfunction (dystonias, spasticity, etc. is the proper administration of the agent into the muscles directly involved in the pathological process. The exact entry of botulinum toxin into the target muscles is essential for successful and safe treatment because its injection into a normal muscle may cause side effects. The most common errors are the incorrect depth and incorrect direction of a needle on insertion. Therefore, the exact injection of the agent particularly into the shallow and deep muscles is a difficult task even for an experienced specialist and requires the use of controlling methods.The European Consensus on Botulinum Toxin Therapy points out that various injection techniques are needed for the better identification of necessary muscles. However, there are currently no reports on the clear advantage of any technique. In our country, injections using palpation and anatomical landmarks have been widely used in routine practice so far; electromyographic monitoring and electrostimulation have been less frequently applied. In recent years, the new method ultrasound-guided injection has continued to grow more popular. This effective, accessible, and easy-to-use method makes it possible to manage a real-time injection process and to ensure the exact entry of the agent into the muscle. This paper is dedicated to a comparative analysis of different injection methods and to a description of the ultrasound-guided technique and its advantages over others. 

  16. International consensus on use of focused ultrasound for painful bone metastases : Current status and future directions

    NARCIS (Netherlands)

    Huisman, Merel; ter Haar, Gail; Napoli, Alessandro; Hananel, Arik; Ghanouni, Pejman; Lövey, György; Nijenhuis, Robbert J; van den Bosch, Maurice A A J; Rieke, Viola; Majumdar, Sharmila; Marchetti, Luca; Pfeffer, Raphael M; Hurwitz, Mark D

    2015-01-01

    Focused ultrasound surgery (FUS), in particular magnetic resonance guided FUS (MRgFUS), is an emerging non-invasive thermal treatment modality in oncology that has recently proven to be effective for the palliation of metastatic bone pain. A consensus panel of internationally recognised experts in

  17. Integrated ultrasound and magnetic resonance imaging for simultaneous temperature and cavitation monitoring during focused ultrasound therapies.

    Science.gov (United States)

    Arvanitis, Costas D; McDannold, Nathan

    2013-11-01

    Ultrasound can be used to noninvasively produce different bioeffects via viscous heating, acoustic cavitation, or their combination, and these effects can be exploited to develop a wide range of therapies for cancer and other disorders. In order to accurately localize and control these different effects, imaging methods are desired that can map both temperature changes and cavitation activity. To address these needs, the authors integrated an ultrasound imaging array into an MRI-guided focused ultrasound (MRgFUS) system to simultaneously visualize thermal and mechanical effects via passive acoustic mapping (PAM) and MR temperature imaging (MRTI), respectively. The system was tested with an MRgFUS system developed for transcranial sonication for brain tumor ablation in experiments with a tissue mimicking phantom and a phantom-filled ex vivo macaque skull. In experiments on cavitation-enhanced heating, 10 s continuous wave sonications were applied at increasing power levels (30-110 W) until broadband acoustic emissions (a signature for inertial cavitation) were evident. The presence or lack of signal in the PAM, as well as its magnitude and location, were compared to the focal heating in the MRTI. Additional experiments compared PAM with standard B-mode ultrasound imaging and tested the feasibility of the system to map cavitation activity produced during low-power (5 W) burst sonications in a channel filled with a microbubble ultrasound contrast agent. When inertial cavitation was evident, localized activity was present in PAM and a marked increase in heating was observed in MRTI. The location of the cavitation activity and heating agreed on average after registration of the two imaging modalities; the distance between the maximum cavitation activity and focal heating was -3.4 ± 2.1 mm and -0.1 ± 3.3 mm in the axial and transverse ultrasound array directions, respectively. Distortions and other MRI issues introduced small uncertainties in the PAM

  18. Transvaginal Ultrasound-Guided Aspiration of Pelvic Abscesses

    Directory of Open Access Journals (Sweden)

    P. J. Corsi

    1999-01-01

    Full Text Available Objective: To assess the utility of a less invasive approach to the care of women with a pelvic abscess, we retrospectively reviewed the outcome of women with pelvic abscesses managed by transvaginal ultrasound-guided aspiration.

  19. [Focused ultrasound therapy: current status and potential applications in neurosurgery].

    Science.gov (United States)

    Dervishi, E; Aubry, J-F; Delattre, J-Y; Boch, A-L

    2013-12-01

    High Intensity Focused Ultrasound (HIFU) therapy is an innovative approach for tissue ablation, based on high intensity focused ultrasound beams. At the focus, HIFU induces a temperature elevation and the tissue can be thermally destroyed. In fact, this approach has been tested in a number of clinical studies for the treatment of several tumors, primarily the prostate, uterine, breast, bone, liver, kidney and pancreas. For transcranial brain therapy, the skull bone is a major limitation, however, new adaptive techniques of phase correction for focusing ultrasound through the skull have recently been implemented by research systems, paving the way for HIFU therapy to become an interesting alternative to brain surgery and radiotherapy. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Focused ultrasound for treatment of uterine myoma: From experimental model to clinical practice

    Directory of Open Access Journals (Sweden)

    Terzić Milan

    2008-01-01

    Full Text Available It is well known that focused ultrasound has a biologic effect on tissue. High intensity focused ultrasound (HIFU on a small target area raises the temperature of the tissue enough to denaturate proteins and cause irreversible cell damage. The tight focus of the ultrasound energy allows delivery of the intended dose to a very precise location. The resulting coagulation necrosis is relatively painless. The application of this method in the human clinical setting has required pilot studies on an animal model. Although the treatment had a high success rate, there was a significant percentage of complications, mainly attributed to the technical drawbacks of the procedure. Therefore, this method has been modified for use in humans, and the HIFU is now guided, monitored and controlled by magnetic resonance imaging (MRI. In October 2004, Food and Drug Adiministration (FDA approved MRI guided focused ultrasound treatment of uterine fibroids in humans. Since then, successful treatment of uterine myomas by HIFU has been performed in thousands of women.

  1. Acupuncture sensation during ultrasound guided acupuncture needling

    Science.gov (United States)

    Park, Jongbae J.; Akazawa, Margeaux; Ahn, Jaeki; Beckman-Harned, Selena; Lin, Feng-Chang; Lee, Kwangjae; Fine, Jason; Davis, Robert T; Langevin, Helene

    2014-01-01

    Background Although acupuncture sensation (also known as de qi) is a cornerstone of traditional acupuncture therapy, most research has accepted the traditional method of defining acupuncture sensation only through subjective patient reports rather than on any quantifiable physiological basis. Purpose To preliminarily investigate the frequency of key sensations experienced while needling to specific, quantifiable tissue levels (TLs) guided by ultrasound (US) imaging. Methods Five participants received needling at two acupuncture points and two control points at four TLs. US scans were used to determine when each TL was reached. Each volunteer completed 32 sets of modified Southampton Needle Sensation Questionnaires. Part one of the study tested sensations experienced at each TL and part two compared the effect of oscillation alone versus oscillation + rotation. Results In all volunteers, the frequency of pricking, sharp sensations was significantly greater in shallower TLs than deeper (p=0.007); the frequency of sensations described as deep, dull and heavy, as spreading, and as electric shocks was significantly greater in deeper TLs than shallower (p=0.002). Sensations experienced did not significantly differ between real and control points within each of three TLs (p>0.05) except TL 4 (p=0.006). The introduction of needle rotation significantly increased deep, dull, heavy sensations, but not pricking and sharp sensations; within each level, the spectrum of sensation experienced during both oscillation + rotation and oscillation alone did not significantly differ between acupuncture and control points. Conclusion The preliminary study indicates a strong connection between acupuncture sensation and both tissue depth and needle rotation. Furthermore, the new methodology has been proven feasible. A further study with an objective measurement is warranted. PMID:21642648

  2. Comparison of ultrasound-guided versus anatomical landmark ...

    African Journals Online (AJOL)

    Background Femoral vein cannulation may be required during major surgery in infants and children and may prove to be life saving under certain conditions. This study compared ultrasound (US)-guided cannulation of the femoral vein in infants with the traditional anatomical landmark-guided technique. Methods Eighty ...

  3. A review of transrectal ultrasound guided prostate biopsies: Is there ...

    African Journals Online (AJOL)

    Objective: We compared our institution's initial experience with transrectal ultrasound-guided (TRUS) prostate biopsies in a single arm prospective study to a historical cohort of finger guided (FG) biopsies. The primary outcome measure was prostate cancer detection. We documented our findings on TRUS including the ...

  4. ultrasound-guided shoulder arthrogram injection

    African Journals Online (AJOL)

    2008-10-15

    Oct 15, 2008 ... Using an aseptic technique and without moving the ultrasound transducer from the desired transverse plane, the needle is advanced into the joint space through the rotator cuff interval, using real-time ultrasound guidance (Fig.2). The needle is inserted into the shoulder approximately midway between the ...

  5. Ultrasound guided core biopsy of suspicious mammographic calcifications using high frequency and power Doppler ultrasound

    International Nuclear Information System (INIS)

    Teh, W.L.; Wilson, A.R.M; Evans, A.J.; Burrell, H.; Pinder, S.E.; Ellis, I.O.

    2000-01-01

    AIM: The pre-operative diagnosis of suspicious mammographic microcalcifications usually requires stereotactic needle biopsy. The aim of this study was to evaluate if high frequency 13 MHz ultrasound (HFUS) and power Doppler (PD) can aid visualization and biopsy of microcalcifications. MATERIALS AND METHODS: Forty-four consecutive patients presenting with microcalcifications without associated mammographic or palpable masses were examined with HFUS and PD. Ultrasound-guided core biopsy (USCB) was performed where possible. Stereotactic biopsy was carried out when US-guided biopsy was unsuccessful. Surgery was performed if a diagnosis of malignancy was made on core biopsy or if the repeat core biopsy was non-diagnostic. RESULTS: Forty-one patients (93%) had ultrasound abnormalities corresponding to mammographic calcification. USCB was performed on 37 patients. In 29/37, USCB obtained a definitive result (78.4%). USCB was non-diagnostic in 4/9 benign (44.4%) and 4/28 (14.3%) malignant lesions biopsied. The complete and absolute sensitivities for malignancy using USCB were 85.7% (24/28) and 81% (23/28), respectively. USCB correctly identified invasive disease in 12/23 (52.2%) cases. There was no significant difference in the presence of abnormal flow on PD between benign and malignant lesions. However, abnormal PD vascularity was present in 43.5% of invasive cancer and was useful in directing successful biopsy in eight cases. CONCLUSION: The combination of high frequency US with PD is useful in the detection and guidance of successful needle biopsy of microcalcifications particularly where there is an invasive focus within larger areas of DCIS. Teh, W.L. (2000)

  6. Usefulness of ultrasound-guided mammotome biopsy for microcalcification

    International Nuclear Information System (INIS)

    Kim, You Me; Park, Hee Boong; Ryu, Jin Woo

    2005-01-01

    To evaluate the usefulness of ultrasound-guided mammotome biopsy for microcalcification and to suggest a new approach for the localization of microcalcifications which are not detected on ultrasound. Twenty-one calcific lesions in 21 women (aged 33-56 years) underwent ultrasound-guided, vacuum-assisted, mammotome biopsy and a mean of 14 specimens per lesion were obtained. Calcification retrieval was defined as identification of calcifications on specimen radiographs. In the 13 cases of calcifications which were not detected on ultrasound imaging, mammotome biopsy was performed after localization of one or two needles at the microcalcifications under mammography-guidance. Radiographs of the specimens and histologic findings were reviewed and scheduled follow-up imaging was performed for evaluation of the complications of biopsy. Ultrasound-guided, vacuum-assisted, mammotome biopsy removed all calcifications in 21 lesions. Eight (38%) lesions showed visible calcification on the ultrasound while 13 (62%) lesions were invisible, which underwent mammotome biopsy after needle localization under mammography-guidance. Surgery revealed DCIS in 1 (4.8%) of 21 lesions, infiltrating ductal carcinoma in two (9.5%), fibroadenomas with calcifications in 6 (28.6%), fibroadenmas with adenosis in 2(9.5%), and fibrocystic change with calcifications in 10 (47.6%). Clinical significant complications did not occur on follow-up examination in any of the cases. Ultrasound-guided, vacuum-assisted, mammotome biopsy was an effective method for microcalcifications on mammogram. The results suggested that mammotome biopsy after mammogram-guided, needle localization is a good alternative method for the diagnosis of microcalcifications which are undetectable in the ultrasound images

  7. Usefulness of ultrasound-guided mammotome biopsy for microcalcification

    Energy Technology Data Exchange (ETDEWEB)

    Kim, You Me [Dankook University Hospital, Seoul (Korea, Republic of); Park, Hee Boong [Park Breast Clinic, Seoul (Korea, Republic of); Ryu, Jin Woo [Cheonan Choongmu Hospital, Cheonan (Korea, Republic of)

    2005-08-15

    To evaluate the usefulness of ultrasound-guided mammotome biopsy for microcalcification and to suggest a new approach for the localization of microcalcifications which are not detected on ultrasound. Twenty-one calcific lesions in 21 women (aged 33-56 years) underwent ultrasound-guided, vacuum-assisted, mammotome biopsy and a mean of 14 specimens per lesion were obtained. Calcification retrieval was defined as identification of calcifications on specimen radiographs. In the 13 cases of calcifications which were not detected on ultrasound imaging, mammotome biopsy was performed after localization of one or two needles at the microcalcifications under mammography-guidance. Radiographs of the specimens and histologic findings were reviewed and scheduled follow-up imaging was performed for evaluation of the complications of biopsy. Ultrasound-guided, vacuum-assisted, mammotome biopsy removed all calcifications in 21 lesions. Eight (38%) lesions showed visible calcification on the ultrasound while 13 (62%) lesions were invisible, which underwent mammotome biopsy after needle localization under mammography-guidance. Surgery revealed DCIS in 1 (4.8%) of 21 lesions, infiltrating ductal carcinoma in two (9.5%), fibroadenomas with calcifications in 6 (28.6%), fibroadenmas with adenosis in 2(9.5%), and fibrocystic change with calcifications in 10 (47.6%). Clinical significant complications did not occur on follow-up examination in any of the cases. Ultrasound-guided, vacuum-assisted, mammotome biopsy was an effective method for microcalcifications on mammogram. The results suggested that mammotome biopsy after mammogram-guided, needle localization is a good alternative method for the diagnosis of microcalcifications which are undetectable in the ultrasound images.

  8. Ultrasound-guided core needle biopsy for breast cancer

    International Nuclear Information System (INIS)

    Naqvi, S.Q.H.; Solangi, R.A.; Memon, M.; Solangi, R.A.

    2008-01-01

    To evaluate the efficacy of ultrasound-guided core needle biopsy (US-CNB) as a preoperative diagnostic modality for breast cancer. Females with solid and/or intermediate breast lesions visualized on ultrasonography. Apart from clinical work-up, all the above mentioned patients underwent ultrasound-guided core needle biopsy and excisional biopsy of their breast lesions. The histopathological diagnosis on ultrasound-guided core needle biopsy was then compared with the findings of the excisional biopsy. Out of the total 93 cases, 47(50.5%) had benign lesions on ultrasound; US-CNB showed 24 as fibroadenomata, four with chronic non-specific mastitis, five chronic suppurative mastitis, one tuberculosis, four fat necrosis, two lactational adenoma and seven cases with benign ductal hyperplasia without atypia. Nine (9.7%) cases showed suspicious abnormality on ultrasound; US-CNB revealed five cases with atypical ductal hyperplasia, one ductal carcinoma in situ and three invasive ductal carcinoma. Thirty seven (39.8%) cases were highly suggestive of malignancy on ultrasound; US-CNB showed 34 as invasive ductal carcinoma, two invasive lobular and one medullary carcinoma. Excisional biopsy confirmed the diagnosis of ultrasound-guided core needle biopsy in all cases except four; one case of chronic suppurative mastitis was diagnosed as that of tuberculosis and three cases of atypial ductal hyperplasia as invasive ductal carcinoma. Hence there was no false positive case, but four (4.3%) false negative cases. The sensitivity of the US-CNB was thus 100% and specificity 91.1%. Ultrasound guided core needle biopsy is a satisfactory procedure for the histopathological diagnosis of breast lesions. Any unsatisfactory, suspicious or atypical change on US-CNB should be followed by an open biopsy. (author)

  9. High-intensity focused ultrasound in the treatment of breast tumours.

    Science.gov (United States)

    Peek, Mirjam C L; Wu, Feng

    2018-01-01

    High-intensity focused ultrasound (HIFU) is a minimally invasive technique that has been used for the treatment of both benign and malignant tumours. With HIFU, an ultrasound (US) beam propagates through soft tissue as a high-frequency pressure wave. The US beam is focused at a small target volume, and due to the energy building up at this site, the temperature rises, causing coagulative necrosis and protein denaturation within a few seconds. HIFU is capable of providing a completely non-invasive treatment without causing damage to the directly adjacent tissues. HIFU can be either guided by US or magnetic resonance imaging (MRI). Guided imaging is used to plan the treatment, detect any movement during the treatment and monitor response in real-time. This review describes the history of HIFU, the HIFU technique, available devices and gives an overview of the published literature in the treatment of benign and malignant breast tumours with HIFU.

  10. The future perspectives in transrectal prostate ultrasound guided biopsy

    Directory of Open Access Journals (Sweden)

    Sung Il Hwang

    2014-12-01

    Full Text Available Prostate cancer is one of the most common neoplasms in men. Transrectal ultrasound (TRUS-guided systematic biopsy has a crucial role in the diagnosis of prostate cancer. However, it shows limited value with gray-scale ultrasound alone because only a small number of malignancies are visible on TRUS. Recently, new emerging technologies in TRUS-guided prostate biopsy were introduced and showed high potential in the diagnosis of prostate cancer. High echogenicity of ultrasound contrast agent reflect the increased status of angiogenesis in tumor. Molecular imaging for targeting specific biomarker can be also used using ultrasound contrast agent for detecting angiogenesis or surface biomarker of prostate cancer. The combination of TRUS-guided prostate biopsy and ultrasound contrast agents can increase the accuracy of prostate cancer diagnosis. Elastography is an emerging ultrasound technique that can provide the information regarding tissue elasticity and stiffness. Tumors are usually stiffer than the surrounding soft tissue. In two types of elastography techniques, shearwave elastography has many potential in that it can provide quantitative information on tissue elasticity. Multiparametric magnetic resonance imaging (MRI from high resolution morphologic and functional magnetic resonance (MR technique enables to detect more prostate cancers. The combination of functional techniques including apparent diffusion coefficient map from diffusion weighted imaging, dynamic contrast enhanced MR and MR spectroscopy are helpful in the localization of the prostate cancer. MR-ultrasound (US fusion image can enhance the advantages of both two modalities. With MR-US fusion image, targeted biopsy of suspicious areas on MRI is possible and fusion image guided biopsy can provide improved detection rate. In conclusion, with recent advances in multiparametric-MRI, and introduction of new US techniques such as contrast-enhanced US and elastography, TRUS-guided biopsy

  11. Numerical simulations of clinical focused ultrasound functional neurosurgery

    Science.gov (United States)

    Pulkkinen, Aki; Werner, Beat; Martin, Ernst; Hynynen, Kullervo

    2014-04-01

    A computational model utilizing grid and finite difference methods were developed to simulate focused ultrasound functional neurosurgery interventions. The model couples the propagation of ultrasound in fluids (soft tissues) and solids (skull) with acoustic and visco-elastic wave equations. The computational model was applied to simulate clinical focused ultrasound functional neurosurgery treatments performed in patients suffering from therapy resistant chronic neuropathic pain. Datasets of five patients were used to derive the treatment geometry. Eight sonications performed in the treatments were then simulated with the developed model. Computations were performed by driving the simulated phased array ultrasound transducer with the acoustic parameters used in the treatments. Resulting focal temperatures and size of the thermal foci were compared quantitatively, in addition to qualitative inspection of the simulated pressure and temperature fields. This study found that the computational model and the simulation parameters predicted an average of 24 ± 13% lower focal temperature elevations than observed in the treatments. The size of the simulated thermal focus was found to be 40 ± 13% smaller in the anterior-posterior direction and 22 ± 14% smaller in the inferior-superior direction than in the treatments. The location of the simulated thermal focus was off from the prescribed target by 0.3 ± 0.1 mm, while the peak focal temperature elevation observed in the measurements was off by 1.6 ± 0.6 mm. Although the results of the simulations suggest that there could be some inaccuracies in either the tissue parameters used, or in the simulation methods, the simulations were able to predict the focal spot locations and temperature elevations adequately for initial treatment planning performed to assess, for example, the feasibility of sonication. The accuracy of the simulations could be improved if more precise ultrasound tissue properties (especially of the

  12. Ultrasound-controlled neuronavigator-guided brain surgery.

    Science.gov (United States)

    Koivukangas, J; Louhisalmi, Y; Alakuijala, J; Oikarinen, J

    1993-07-01

    The development of a unique neurosurgical navigator is described and a preliminary series of seven cases of intracerebral lesions approached with the assistance of this neuronavigation system under ultrasound control is presented. The clinical series included five low-grade astrocytomas, one chronic intracerebral hematoma, and one porencephalic cyst. Management procedures included biopsy in all cases, drainage of the hematoma, and endoscopy and fenestration for the cyst. The features of the neuronavigation system are interactive reconstructions of preoperative computerized tomography and magnetic resonance imaging data, corresponding intraoperative ultrasound images, versatility of the interchangeable end-effector instruments, graphic presentation of instruments on the reconstructed images, and voice control of the system. The principle of a common axis in the reconstructed images served to align the navigational pointer, biopsy guide, endoscope guide, ultrasound transducer, and surgical microscope to the brain anatomy. Intraoperative ultrasound imaging helped to verify the accuracy of the neuronavigator and check the results of the procedures. The arm of the neuronavigation system served as a holder for instruments, such as the biopsy guide, endoscope guide, and ultrasound transducer, in addition to functioning as a navigational pointer. Also, the surgical microscope was aligned with the neuronavigator for inspection and biopsy of the hematoma capsule to rule out tumor etiology. Voice control freed the neurosurgeon from manual exercises during start-up and calibration of the system.

  13. High-intensity focused ultrasound for potential treatment of polycystic ovary syndrome: toward a noninvasive surgery.

    Science.gov (United States)

    Shehata, Islam A; Ballard, John R; Casper, Andrew J; Hennings, Leah J; Cressman, Erik; Ebbini, Emad S

    2014-02-01

    To investigate the feasibility of using high-intensity focused ultrasound (HIFU), under dual-mode ultrasound arrays (DMUAs) guidance, to induce localized thermal damage inside ovaries without damage to the ovarian surface. Laboratory feasibility study. University-based laboratory. Ex vivo canine and bovine ovaries. DMUA-guided HIFU. Detection of ovarian damage by ultrasound imaging, gross pathology, and histology. It is feasible to induce localized thermal damage inside ovaries without damage to the ovarian surface. DMUA provided sensitive imaging feedback regarding the anatomy of the treated ovaries and the ablation process. Different ablation protocols were tested, and thermal damage within the treated ovaries was histologically characterized. The absence of damage to the ovarian surface may eliminate many of the complications linked to current laparoscopic ovarian drilling (LOD) techniques. HIFU may be used as a less traumatic tool to perform LOD. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  14. Ultrasound guided percutaneous fine needle aspiration biopsy ...

    African Journals Online (AJOL)

    )-guided percutaneous fine needle aspiration biopsy (PFNAB)/US-guided percutaneous needle core biopsy (PNCB) of abdominal lesions is efficacious in diagnosis, is helpful in treatment choice, to evaluate whether various other investigations ...

  15. Non-Thermal High-Intensity Focused Ultrasound for Breast Cancer Therapy

    Science.gov (United States)

    2013-07-01

    Comet assay reveals DNA strand breaks induced by ultrasonic cavitation in vitro, Ultrasound in medicine & biology 1995; 21: 841-8. 3. Dalecki D...doxorubicin, focused ultrasound , HIFU, prostate cancer I. INTRODUCTION Pulsed high-intensity focused ultrasound (pFUS) is able to create acoustic cavitation ... ultrasound for breast cancer therapy PRINCIPAL INVESTIGATOR: Chang Ming (Charlie) Ma, Ph.D

  16. Improved heating efficiency with High-Intensity Focused Ultrasound using a new ultrasound source excitation.

    Science.gov (United States)

    Bigelow, Timothy A

    2009-01-01

    High-Intensity Focused Ultrasound (HIFU) is quickly becoming one of the best methods to thermally ablate tissue noninvasively. Unlike RF or Laser ablation, the tissue can be destroyed without inserting any probes into the body minimizing the risk of secondary complications such as infections. In this study, the heating efficiency of HIFU sources is improved by altering the excitation of the ultrasound source to take advantage of nonlinear propagation. For ultrasound, the phase velocity of the ultrasound wave depends on the amplitude of the wave resulting in the generation of higher harmonics. These higher harmonics are more efficiently converted into heat in the body due to the frequency dependence of the ultrasound absorption in tissue. In our study, the generation of the higher harmonics by nonlinear propagation is enhanced by transmitting an ultrasound wave with both the fundamental and a higher harmonic component included. Computer simulations demonstrated up to a 300% increase in temperature increase compared to transmitting at only the fundamental for the same acoustic power transmitted by the source.

  17. Ultrasound guided reduction of childhood intussusception

    International Nuclear Information System (INIS)

    Yoon, Chong Hyun; Kim, Han Suk

    1986-01-01

    Following on from diagnosis using ultrasound, hydrostatic reduction using saline enema under ultrasound guidance was tried in 20 cases of childhood intussusception. The conclusions were as follows: 1. Success rates of saline enema under ultrasound guidance during a first-8 month period (P1) and a second-10 month period (P2) were 55.6% (5/9) and 54.5% (6/11) respectively. Average success rate was 55% (11/20). 2. During the periods of P1 and P2, no case was reduced by barium enema in 6 cases of failed reduction with saline enema. 3. During the period of P2, 5 cases of successful reduction with saline enema were confirmed by clinical follow-up without barium enema. 4. During the periods of P1 and P2, 9 cases of failed reduction with saline enema were operated, resulting in 6 cases of segmental resection and 3 cases of manual reduction. 5. The obvious advantages of this method are: 1. No radiation hazard. 2. No fear of barium peritonitis. 3. Detection of leading point. 6. With above results, this method could completely replace barium enema. And ultrasonography should be the initial study in the evaluation of intussusception in children and then if necessary, saline enema under ultrasound guidance should be done.

  18. MRI-guided vacuum-assisted breast biopsy: comparison with stereotactically guided and ultrasound-guided techniques

    Energy Technology Data Exchange (ETDEWEB)

    Imschweiler, Thomas; Freiwald, Bianka; Kubik-Huch, Rahel A. [Kantonspital Baden AG, Institute for Radiology, Baden (Switzerland); Haueisen, Harald [Kantonspital Aarau AG, Institute for Radiology, Aarau (Switzerland); Kampmann, Gert [Clinica Sant' Anna, Lugano, Sorengo (Switzerland); Rageth, Luzi [Adjumed Services AG, Zurich (Switzerland); Seifert, Burkhardt [Institute for Social and Preventive Medicine, University of Zurich, Division of Biostatistics, Zuerich (Switzerland); Rageth, Christoph [Breast Centre, Zurich (Switzerland)

    2014-01-15

    To analyse the development of MRI-guided vacuum-assisted biopsy (VAB) in Switzerland and to compare the procedure with stereotactically guided and ultrasound-guided VAB. We performed a retrospective analysis of VABs between 2009 and 2011. A total of 9,113 VABs were performed. Of these, 557 were MRI guided. MRI-guided VAB showed the highest growth rate (97 %) of all three procedures. The technical success rates for MRI-guided, stereotactically guided and ultrasound-guided VAB were 98.4 % (548/557), 99.1 % (5,904/5,960) and 99.6 % (2,585/2,596), respectively. There were no significant differences (P = 0.12) between the MRI-guided and the stereotactically guided procedures. The technical success rate for ultrasound-guided VAB was significantly higher than that for MRI-guided VAB (P < 0.001). There were no complications using MRI-guided VAB requiring open surgery. The malignancy diagnosis rate for MRI-guided VAB was similar to that for stereotactically guided VAB (P = 0.35). MRI-guided VAB is a safe and accurate procedure that provides insight into clinical breast findings. (orig.)

  19. Ultrasound-guided percutaneous biopsy of digestive tract lesions

    International Nuclear Information System (INIS)

    Gil, S.; Martin, I.; Ballesteros, J. M.; Gomez, C.; Marco, S. F.; Fernandez, P.

    1999-01-01

    To present our experience in ultrasound-guided percutaneous biopsy of lesions located in the digestive tract. We performed ultrasound-guided percutaneous biopsy in 14 patients (10 men and 4 women) ranging in age from 7 to 71 years (mean; 519 years). The lesions were located throughout the digestive tract, from the pyriform sinus to the sigmoid colon. The biopsy was carried out with a 5 MHz convex probe equipped with a device to direct the needle. An 18G automatic needle or a 20G Chiba needle was used to obtain specimens for histological study in every case, and additional samples were collected with a 22G needle for cytological examination in 13 of the patients. The ultrasound images corresponded to pseudokidney in 9 cases and extrinsic masses in 5. The diagnosis was obtained from the histological examination in every case (100%) and from cytology in 6 (44.4%), the latter results were less specific. The only complication corresponded to a case of bilioperitoneum. Ultrasound-guided percutaneous biopsy is a suitable technique for the histological diagnosis of those lesions of the digestive tract that are visible in ultrasound images, but that for some reason can not be examined by endoscopic biopsy. (Author) 20 refs

  20. Amoebic liver abscess: Drained by ultrasound guided percutaneous ...

    African Journals Online (AJOL)

    Summary: Amoebic Liver Abscess in a 20-month-old child: A case of amoebic liver abscess in a Nigerian child is presented. Management consisted of 10days course of Metronidazole and 5days course of Tinidazole without improvement. This was followed by four sessions of ultrasound guided percutaneous needle ...

  1. Ultrasound-guided wire localization of lesions detected on ...

    African Journals Online (AJOL)

    Background: Wire localization for planned surgical treatment in the management of breast cancer is underutilized in our environment. The objective of this study is to assess the role of ultrasound-guided wire localization of breast masses detected on screening mammography and its impact on biopsy and breast ...

  2. Ultrasound-guided endoscopic transgastric drainage of a post ...

    African Journals Online (AJOL)

    Despite of a number of techniques in the armentarium of the paediatric surgeon, the management of pancreatic pseudocysts remains a challenge. We report on a case of a 5-year-old child with a post-traumatic pancreatic pseudocyst who was successfully treated with endoscopic ultrasound-guided transgastric approach.

  3. Practice guidelines for endoscopic ultrasound-guided celiac plexus neurolysis

    DEFF Research Database (Denmark)

    Wyse, Jonathan M; Battat, Robert; Sun, Siyu

    2017-01-01

    OBJECTIVES: The objective of guideline was to provide clear and relevant consensus statements to form a practical guideline for clinicians on the indications, optimal technique, safety and efficacy of endoscopic ultrasound guided celiac plexus neurolysis (EUS-CPN). METHODS: Six important clinical...

  4. Practice guidelines for endoscopic ultrasound-guided celiac plexus neurolysis

    NARCIS (Netherlands)

    Wyse, J.M. (Jonathan M.); Battat, R. (Robert); Sun, S. (Siyu); A. Saftoiu (Adrian); Siddiqui, A.A. (Ali A.); Leong, A.T. (Ang Tiing); Arias, B.L.A. (Brenda Lucia Arturo); Fabbri, C. (Carlo); Adler, D.G. (Douglas G.); Santo, E. (Erwin); Kalaitzakis, E. (Evangelos); Artifon, E. (Everson); Mishra, G. (Girish); Okasha, H.H. (Hussein Hassan); J.-W. Poley (Jan-Werner); Guo, J. (Jintao); Vila, J.J. (Juan J.); Lee, L.S. (Linda S.); Sharma, M. (Malay); Bhutani, M.S. (Manoop S.); M. Giovannini (Marcello); Kitano, M. (Masayuki); Eloubeidi, M.A. (Mohamad Ali); Khashab, M.A. (Mouen A.); Nguyen, N.Q. (Nam Q.); Saxena, P. (Payal); Vilmann, P. (Peter); Fusaroli, P. (Pietro); Garg, P.K. (Pramod Kumar); Ho, S. (Sammy); Mukai, S. (Shuntaro); Carrara, S. (Silvia); Sridhar, S. (Subbaramiah); S. Lakhtakia (S.); Rana, S.S. (Surinder S.); Dhir, V. (Vinay); Sahai, A.V. (Anand V.)

    2017-01-01

    textabstractObjectives: The objective of guideline was to provide clear and relevant consensus statements to form a practical guideline for clinicians on the indications, optimal technique, safety and efficacy of endoscopic ultrasound guided celiac plexus neurolysis (EUS-CPN). Methods: Six important

  5. A retrospective analysis of ultrasound-guided large core needle ...

    African Journals Online (AJOL)

    A retrospective analysis of ultrasound-guided large core needle biopsies of breast lesions at a regional public hospital in Durban, KwaZulu-Natal, South Africa. ... Objective: To assess the influence of technical variables on the diagnostic yield of breast specimens obtained by using US-LCNB, and the sensitivity of detecting ...

  6. Ultrasound-guided continuous phrenic nerve block for persistent hiccups.

    NARCIS (Netherlands)

    Renes, S.H.; Geffen, G.J. van; Rettig, H.C.; Gielen, M.J.M.; Scheffer, G.J.

    2010-01-01

    BACKGROUND: Phrenic nerve block can be performed and repeated if necessary for persistent hiccups, when conservative and pharmacological treatment is unsuccessful. We report the first description of an in-plane ultrasound (US)-guided phrenic nerve block (PhNB) with a catheter, after US investigation

  7. Ultrasound-guided nerve block for inguinal hernia repair

    DEFF Research Database (Denmark)

    Bærentzen, Finn; Maschmann, Christian; Jensen, Kenneth

    2012-01-01

    Open inguinal hernia repair in adults is considered a minor surgical procedure but can be associated with significant pain. We aimed to evaluate acute postoperative pain management in male adults randomized to receive an ultrasound-guided ilioinguinal and iliohypogastric nerve block administered...

  8. Ultrasound-guided needle aspiration of parotid abscess

    Directory of Open Access Journals (Sweden)

    André Takahashi

    2012-01-01

    Full Text Available Ultrasound (US has been used as a tool for parotid abscess diagnosis and treatment. The present article aimed to report a case of 72-year-old woman with parotid abscess treated by US-guided needle aspiration and conventional surgical drainage. Along with the clinical report, indications, advantages, and limitations of the method are discussed.

  9. Ultrasound guided percutaneous fine needle aspiration biopsy ...

    African Journals Online (AJOL)

    2011-06-15

    Jun 15, 2011 ... guided PFNAB/US-guided PNCB was the diagnostic test in 23.33% cases. It confirmed a highly ..... provides guidance in multiple axial, longitudinal and .... Source of Support: Nil, Con.ict of Interest: None declared. Gani, et al.

  10. Technical characterization of an ultrasound source for noninvasive thermoablation by high-intensity focused ultrasound.

    Science.gov (United States)

    Köhrmann, K U; Michel, M S; Steidler, A; Marlinghaus, E; Kraut, O; Alken, P

    2002-08-01

    To develop a generator for high-intensity focused ultrasound (HIFU, a method of delivering ultrasonic energy with resultant heat and tissue destruction to a tight focus at a selected depth within the body), designed for extracorporeal coupling to allow various parenchymal organs to be treated. The ultrasound generated by a cylindrical piezo-ceramic element is focused at a depth of 10 cm using a parabolic reflector with a diameter of 10 cm. A diagnostic B-mode ultrasonographic transducer is integrated into the source to allow the focus to be located in the target area. The field distribution of the sound pressure was measured in degassed water using a needle hydrophone. An ultrasound-force balance was used to determine the acoustic power. These measurements allowed the spatially averaged sound intensity to be calculated. The morphology and extent of tissue necrosis induced by HIFU was examined on an ex-vivo kidney model. The two-dimensional field distribution resulted in an approximately ellipsoidal focus of 32 x 4 mm (- 6 dB). The spatially maximum averaged sound intensity was 8591 W/cm2 at an electrical power of 400 W. The lesion caused to the ex-vivo kidney at this maximum generator power with a pulse duration of 2 s was a clearly delineated ellipsoidal coagulation necrosis up to 8.8 x 2.3 mm (length x width) and with central liquefied necrosis of 7.9 x 1.9 mm. This newly developed ultrasound generator with a focal length of 10 cm can induce clear necrosis in parenchymal tissue. Because of its specific configuration and the available power range of the ultrasound generator, there is potential for therapeutic noninvasive ablation of tissue deep within a patient's body.

  11. Neurologic Outcomes After Low-Volume, Ultrasound-Guided Interscalene Block and Ambulatory Shoulder Surgery.

    Science.gov (United States)

    Rajpal, Gaurav; Winger, Daniel G; Cortazzo, Megan; Kentor, Michael L; Orebaugh, Steven L

    2016-01-01

    Postoperative neurologic symptoms after interscalene block and shoulder surgery have been reported to be relatively frequent. Reports of such symptoms after ultrasound-guided block have been variable. We evaluated 300 patients for neurologic symptoms after low-volume, ultrasound-guided interscalene block and arthroscopic shoulder surgery. Patients underwent ultrasound-guided interscalene block with 16 to 20 mL of 0.5% bupivacaine or a mix of 0.2% bupivacaine/1.2% mepivacaine solution, followed by propofol/ketamine sedation for ambulatory arthroscopic shoulder surgery. Patients were called at 10 days for evaluation of neurologic symptoms, and those with persistent symptoms were called again at 30 days, at which point neurologic evaluation was initiated. Details of patient demographics and block characteristics were collected to assess any association with persistent neurologic symptoms. Six of 300 patients reported symptoms at 10 days (2%), with one of these patients having persistent symptoms at 30 days (0.3%). This was significantly lower than rates of neurologic symptoms reported in preultrasound investigations with focused neurologic follow-up and similar to other studies performed in the ultrasound era. There was a modest correlation between the number of needle redirections during the block procedure and the presence of postoperative neurologic symptoms. Ultrasound guidance of interscalene block with 16- to 20-mL volumes of local anesthetic solution results in a lower frequency of postoperative neurologic symptoms at 10 and 30 days as compared with investigations in the preultrasound period.

  12. Ultrasound probe and needle-guide calibration for robotic ultrasound scanning and needle targeting.

    Science.gov (United States)

    Kim, Chunwoo; Chang, Doyoung; Petrisor, Doru; Chirikjian, Gregory; Han, Misop; Stoianovici, Dan

    2013-06-01

    Image-to-robot registration is a typical step for robotic image-guided interventions. If the imaging device uses a portable imaging probe that is held by a robot, this registration is constant and has been commonly named probe calibration. The same applies to probes tracked by a position measurement device. We report a calibration method for 2-D ultrasound probes using robotic manipulation and a planar calibration rig. Moreover, a needle guide that is attached to the probe is also calibrated for ultrasound-guided needle targeting. The method is applied to a transrectal ultrasound (TRUS) probe for robot-assisted prostate biopsy. Validation experiments include TRUS-guided needle targeting accuracy tests. This paper outlines the entire process from the calibration to image-guided targeting. Freehand TRUS-guided prostate biopsy is the primary method of diagnosing prostate cancer, with over 1.2 million procedures performed annually in the U.S. alone. However, freehand biopsy is a highly challenging procedure with subjective quality control. As such, biopsy devices are emerging to assist the physician. Here, we present a method that uses robotic TRUS manipulation. A 2-D TRUS probe is supported by a 4-degree-of-freedom robot. The robot performs ultrasound scanning, enabling 3-D reconstructions. Based on the images, the robot orients a needle guide on target for biopsy. The biopsy is acquired manually through the guide. In vitro tests showed that the 3-D images were geometrically accurate, and an image-based needle targeting accuracy was 1.55 mm. These validate the probe calibration presented and the overall robotic system for needle targeting. Targeting accuracy is sufficient for targeting small, clinically significant prostatic cancer lesions, but actual in vivo targeting will include additional error components that will have to be determined.

  13. MRI feedback temperature control for focused ultrasound surgery

    International Nuclear Information System (INIS)

    Vanne, A; Hynynen, K

    2003-01-01

    A temperature feedback controller routine using a physical model for temperature evolution was developed for use with focused ultrasound surgery. The algorithm for the controller was a multi-input, single-output linear quadratic regulator (LQR) derived from Pennes' bioheat transfer equation. The controller was tested with simulated temperature data that had the same characteristics as those obtained with magnetic resonance imaging (MRI). The output of the controller was the appropriate power level to be used by the transducer. Tissue parameters estimated prior to the simulated treatments were used to determine the controller parameters. The controller performance was simulated in three dimensions with varying system parameters, and sufficient temperature tracking was achieved. The worst-case overshoot was 7 deg. C and the steady-state error was 5 deg. C. The simulated behaviour of the controller suggests satisfactory performance and that the controller may be useful in controlling the power output during MRI-monitored ultrasound surgery

  14. How to achieve ultrasound-guided femoral venous access: the new standard of care in the electrophysiology laboratory.

    Science.gov (United States)

    Wiles, Benedict M; Child, Nicholas; Roberts, Paul R

    2017-06-01

    Bedside vascular ultrasound machines are increasingly available. They are used to facilitate safer vascular access across a number of different specialties. In the electrophysiology laboratory however, where patients are frequently anticoagulated and require the insertion of multiple venous sheaths, anatomical landmark techniques predominate. Despite the high number of vascular complications associated with electrophysiological procedures and the increasing evidence to support its use in electrophysiology, ultrasound remains underutilised. A new standard of care is required. A comprehensive technical report, providing a detailed explanation of this important technique, will provide other electrophysiology centres with the knowledge and justification for adopting ultrasound guidance as their standard practice. We review the increasing body of evidence which demonstrates that routine ultrasound usage can substantially improve the safety of femoral venous access in the electrophysiology laboratory. We offer a comprehensive technical report to guide operators through the process of ultrasound-guided venous access, with a specific focus on the electrophysiology laboratory. Additionally, we detail a novel technique which utilises real-time colour Doppler ultrasound to accurately identify needle tip location during venous puncture. The use of vascular ultrasound to guide femoral venous cannulation is rapid, inexpensive and easily learnt. Ultrasound is readily available and offers the potential to significantly reduce vascular complications in the unique setting of the electrophysiology laboratory. Ultrasound guidance to achieve femoral venous access should be the new standard of care in electrophysiology.

  15. Ultrasound-guided biopsy and drainage

    International Nuclear Information System (INIS)

    Ott, R.C.; Wellauer, J.

    1985-01-01

    This book discusses the ultrasound (US) biopsy techniques, cytology, histology, and physics. The emphasis is on use of US guidance, as the authors find that virtually all lesions are visible at US scanning and they thus save valuable time on the computer tomographic scanner. The authors present in great detail their considerable work in designing needles that are readily visible at US scanning and can also collect good cytologic and histologic material. Biopsy techniques are discussed separately for each organ system. The accuracy of these techniques in over 3,000 of the author's cases is presented

  16. Ultrasound-guided central venous access using Google Glass.

    Science.gov (United States)

    Wu, Teresa S; Dameff, Christian J; Tully, Jeffrey L

    2014-12-01

    The use of ultrasound during invasive bedside procedures is quickly becoming the standard of care. Ultrasound machine placement during procedures often requires the practitioner to turn their head during the procedure to view the screen. Such turning has been implicated in unintentional hand movements in novices. Google Glass is a head-mounted computer with a specialized screen capable of projecting images and video into the view of the wearer. Such technology may help decrease unintentional hand movements. Our aim was to evaluate whether or not medical practitioners at various levels of training could use Google Glass to perform an ultrasound-guided procedure, and to explore potential advantages of this technology. Forty participants of varying training levels were randomized into two groups. One group used Google Glass to perform an ultrasound-guided central line. The other group used traditional ultrasound during the procedure. Video recordings of eye and hand movements were analyzed. All participants from both groups were able to complete the procedure without difficulty. Google Glass wearers took longer to perform the procedure at all training levels (medical student year 1 [MS1]: 193 s vs. 77 s, p > 0.5; MS4: 197s vs. 91s, p ≤ 0.05; postgraduate year 1 [PGY1]: 288s vs. 125 s, p > 0.5; PGY3: 151 s vs. 52 s, p ≤ 0.05), and required more needle redirections (MS1: 4.4 vs. 2.0, p > 0.5; MS4: 4.8 vs. 2.8, p > 0.5; PGY1: 4.4 vs. 2.8, p > 0.5; PGY3: 2.0 vs. 1.0, p > 0.5). In this study, it was possible to perform ultrasound-guided procedures with Google Glass. Google Glass wearers, on average, took longer to gain access, and had more needle redirections, but less head movements were noted. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Endobronchial ultrasound elastography: a new method in endobronchial ultrasound-guided transbronchial needle aspiration.

    Science.gov (United States)

    Jiang, Jun-Hong; Turner, J Francis; Huang, Jian-An

    2015-12-01

    TBNA through the flexible bronchoscope is a 37-year-old technology that utilizes a TBNA needle to puncture the bronchial wall and obtain specimens of peribronchial and mediastinal lesions through the flexible bronchoscope for the diagnosis of benign and malignant diseases in the mediastinum and lung. Since 2002, the Olympus Company developed the first generation ultrasound equipment for use in the airway, initially utilizing an ultrasound probe introduced through the working channel followed by incoroporation of a fixed linear ultrasound array at the distal tip of the bronchoscope. This new bronchoscope equipped with a convex type ultrasound probe on the tip was subsequently introduced into clinical practice. The convex probe (CP)-EBUS allows real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) of mediastinal and hilar lymph nodes. EBUS-TBNA is a minimally invasive procedure performed under local anesthesia that has been shown to have a high sensitivity and diagnostic yield for lymph node staging of lung cancer. In 10 years of EBUS development, the Olympus Company developed the second generation EBUS bronchoscope (BF-UC260FW) with the ultrasound image processor (EU-M1), and in 2013 introduced a new ultrasound image processor (EU-M2) into clinical practice. FUJI company has also developed a curvilinear array endobronchial ultrasound bronchoscope (EB-530 US) that makes it easier for the operator to master the operation of the ultrasonic bronchoscope. Also, the new thin convex probe endobronchial ultrasound bronchoscope (TCP-EBUS) is able to visualize one to three bifurcations distal to the current CP-EBUS. The emergence of EBUS-TBNA has also been accompanied by innovation in EBUS instruments. EBUS elastography is, then, a new technique for describing the compliance of structures during EBUS, which may be of use in the determination of metastasis to the mediastinal and hilar lymph nodes. This article describes these new EBUS

  18. Ultrasound Guided Percutaneous Nephrostomy: Experience at ...

    African Journals Online (AJOL)

    Background: Obstructive uropathy is a common problem in urologic practice; temporary relief of obstruction in the upper tract poses a significant challenge. Ultrasound‑guided percutaneous nephrostomy (PCN) is an option for upper tract drainage; compared to fluoroscopic guidance, it is readily available, affordable, and not ...

  19. Toward real-time temperature monitoring in fat and aqueous tissue during magnetic resonance-guided high-intensity focused ultrasound using a three-dimensional proton resonance frequency T1 method.

    Science.gov (United States)

    Diakite, Mahamadou; Odéen, Henrik; Todd, Nick; Payne, Allison; Parker, Dennis L

    2014-07-01

    To present a three-dimensional (3D) segmented echoplanar imaging (EPI) pulse sequence implementation that provides simultaneously the proton resonance frequency shift temperature of aqueous tissue and the longitudinal relaxation time (T1 ) of fat during thermal ablation. The hybrid sequence was implemented by combining a 3D segmented flyback EPI sequence, the extended two-point Dixon fat and water separation, and the double flip angle T1 mapping techniques. High-intensity focused ultrasound (HIFU) heating experiments were performed at three different acoustic powers on excised human breast fat embedded in ex vivo porcine muscle. Furthermore, T1 calibrations with temperature in four different excised breast fat samples were performed, yielding an estimate of the average and variation of dT1 /dT across subjects. The water only images were used to mask the complex original data before computing the proton resonance frequency shift. T1 values were calculated from the fat-only images. The relative temperature coefficients were found in five fat tissue samples from different patients and ranged from 1.2% to 2.6%/°C. The results demonstrate the capability of real-time simultaneous temperature mapping in aqueous tissue and T1 mapping in fat during HIFU ablation, providing a potential tool for treatment monitoring in organs with large fat content, such as the breast. Copyright © 2013 Wiley Periodicals, Inc.

  20. The comparative study of CT guided and ultrasound guided percutaneous ethanol injection in the treatment of intra-abdominal cyst

    International Nuclear Information System (INIS)

    Li Heping; Yang Jianyong; Chen Wei; Zhuang Wenquan; Huang Yulian; Chen Jianye

    2005-01-01

    Objective: An comparative study of the interventional approach of CT guided and ultiasound guided percutaneous ethanol injection(PEI) in the treatment of intra-abdominal cyst. Methods: CT guided PEI was performed in the treatment of intra-abdominal cyst in 38 patients while ultrasound guided PEI was performed in 45 cases. Results: The puncture procedure of CT guided PEI was totally performed 83 times in treating 56 intra-abdominal cysts in 38 patients and CT guided PEI was unsuccessful in 6 patients. The puncture procedure of ultrasound guided PEI were performed 87 times in treating 71 intra-abdominal cysts in 55 patients and ultrasound guided PEI only failed only in 1 patient. Conclusion: Ultrasound guided PEI is superior to CT guided PEI in the treatment of intra-abdominal cyst. (authors)

  1. Pre-puncture ultrasound guided epidural insertion before vaginal delivery.

    Science.gov (United States)

    Nassar, Mahmoud; Abdelazim, Ibrahim A

    2015-10-01

    Palpation method is widely used in clinical practice to identify the puncture site during combined spinal-epidural (CSE) blocks. Tuffier's line, is an anatomical landmark between two iliac crests (inter-cristal), which is widely used to identify the puncture site during CSE blocks is not always an indicator for specific vertebral level or inter-vertebral space. One hundred and Ten (110) women were scheduled for normal vaginal delivery and were randomized into two equal groups; palpation group and an ultrasound guided group to detect the efficacy of puncture ultrasound before CSE blocks to increase chances of successful CSE procedure on the first attempt and to reduce the number of attempts or punctures during insertion of CSE catheter. There were no significant differences between two studied groups regarding; maternal age, weight and height, while, there was a significant difference between two studied groups regarding; parity. Percentage of successful CSE procedure on the first attempt was significantly higher (67.27%) in ultrasound compared to palpation group (40%). Number of punctures (attempts) were significantly less in ultrasound (1.2 ± 0.6) compared to palpation group (2.3 ± 0.8) and the number of redirections was also significantly less in ultrasound (1.4 ± 0.5) compared to palpation group (2.8 ± 1.6). Although, time to identify puncture site was significantly longer in ultrasound compared to palpation group and total procedure time was longer in ultrasound (9.1 ± 1.5 min) compared to palpation group (6.2 ± 1.2 min), there was no significant difference between two studied groups regarding; time to identify puncture site and total procedure time. Two cases of dural puncture in palpation versus no cases in ultrasound group and two cases of intravascular catheter placement (one in each group), with no significant difference between two groups. Pre- puncture ultrasound guided epidural insertion before vaginal delivery, increases the chance of a

  2. EFSUMB Guidelines on Interventional Ultrasound (INVUS), Part IV - EUS-guided interventions

    DEFF Research Database (Denmark)

    Jenssen, C; Hocke, M; Fusaroli, P

    2016-01-01

    The fourth part of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Guidelines on Interventional Ultrasound describes general aspects of endoscopic ultrasound-guided diagnostic and therapeutic interventions and assesses the evidence for endoscopic ultrasound-gu...

  3. Ultrasound-guided interventional therapy for recurrent ovarian chocolate cysts.

    Science.gov (United States)

    Wang, Lu-Lu; Dong, Xiao-Qiu; Shao, Xiao-Hui; Wang, Si-Ming

    2011-10-01

    The aim of this study was to determine the effectiveness of ultrasound-guided interventional therapy in the treatment of postoperative recurrent chocolate cysts. The 198 patients enrolled in this study were divided into three groups. In group 1, the saline washing group, the cavity of the cyst was washed thoroughly with warm saline. In group 2, the ethanol short-time retention group, after washing with saline, the cyst was injected with 95% ethanol with a volume of half of the fluid aspirated from the cyst. Ten minutes later, the rest of the ethanol was aspirated. In group 3, the ethanol retention group, the procedures were the same as with the ethanol short-time retention group, except that 95% of the ethanol was retained in the cyst. An ultrasound examination was performed in the third, sixth and 12th months after therapy. The chocolate cyst cure rate was significantly higher in the ethanol retention group (96%, 66/69) than in the ethanol short-time retention group (82%, 56/68) and no case was cured in the first group (saline washing). We conclude that ultrasound-guided injection and 95% ethanol retention are an effective therapy for the treatment of postoperative recurrent chocolate cysts. Copyright © 2011 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  4. High Intensity Focused Ultrasound Ablation of Pancreatic Neuroendocrine Tumours: Report of Two Cases

    International Nuclear Information System (INIS)

    Orgera, Gianluigi; Krokidis, Miltiadis; Monfardini, Lorenzo; Bonomo, Guido; Della Vigna, Paolo; Fazio, Nicola; Orsi, Franco

    2011-01-01

    We describe the use of ultrasound-guided high-intensity focused ultrasound (HIFU) for ablation of two pancreatic neuroendocrine tumours (NETs; insulinomas) in two inoperable young female patients. Both suffered from episodes of severe nightly hypoglycemia that was not efficiently controlled by medical treatment. After HIFU ablation, local disease control and symptom relief were achieved without postinterventional complications. The patients remained free of symptoms during 9-month follow-up. The lesions appeared to be decreased in volume, and there was decreased enhancing pattern in the multidetector computed tomography control (MDCT). HIFU is likely to be a valid alternative for symptoms control in patients with pancreatic NETs. However, currently the procedure should be reserved for inoperable patients for whom symptoms cannot be controlled by medical therapy.

  5. Ultrasound guided aspiration cytology of neck mass except thyroid mass

    International Nuclear Information System (INIS)

    Kim, Myeong Jin; Lee, Jong Tae; Yoo, Hyung Sik; Suh, Jung Ho; Park, Cheong Soo; Lee, Gwang Gil

    1988-01-01

    Results of ultrasound guided aspiration cytology of extrathyroidal neck masses of 73 patients were reviewed. Included cases were 23 malignant lesions; 16 metastatic tumors, 4 lymphomas, 3 salivary gland tumors and 50 benign lesions: 24 tuberculous lymphadenites, 15 abscess, 3 benign lymph node hyperplasias, etc. There were one case of false negative and none of false positive result for malignancy. In two cases of malignancy, insufficient cellular material was obtained. In one case of lymphoma, and a benign lymph node hyperplasia, it was difficult to distinguish between benignancy and malignancy on cytologic smear. For the malignant lesions, sensitivity was 83%, specificity was 98%, and overall accuracy was 93%. There were none who had suffered adverse effect from the procedure. Ultrasound guided aspiration cytology seems to be simple, accurate and safe diagnostic modality for neck masses especially in condition that malignancy can not be excluded

  6. Ultrasound-guided antegrade pyelography of renal transplants

    International Nuclear Information System (INIS)

    Wernecke, K.; Heckemann, R.; Rehwald, U.; Ringert, R.H.; Essen Univ.

    1983-01-01

    The indications for, and technique of, ultrasound-guided antegrade pyelography of renal transplants are illustrated by eight patients. Because of the detailed anatomical information which the antegrade method provides, it is superior to other diagnostic methods for the investigation of ureteric obstruction or fistulae. The severity of renal pelvis dilatation as shown by sonography must not be taken as a criterian for the grade of obstruction, since transplants may show dilated collecting systems, even in the absence of obstruction. In our view, real time sonography with a suitable probe provides the best means of achieving successful puncture of the renal pelvis. The combination of ultrasound-guided puncture and radiological contrast examination of the ureter is the best diagnostic method available and lead, in all eight cases, to immediate and definitive treatment. (orig.)

  7. In vitro characterization of perfluorocarbon droplets for focused ultrasound therapy

    Energy Technology Data Exchange (ETDEWEB)

    Schad, Kelly C; Hynynen, Kullervo, E-mail: khynynen@sri.utoronto.c [Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, Ontario M4N 3M5 (Canada); Department of Medical Biophysics, University of Toronto (Canada)

    2010-09-07

    Focused ultrasound therapy can be enhanced with microbubbles by thermal and cavitation effects. However, localization of treatment is difficult as bioeffects can occur outside of the target region. Spatial control of bubbles can be achieved by ultrasound-induced conversion of liquid perfluorocarbon droplets to gas bubbles. This study was undertaken to determine the acoustic parameters for bubble production by droplet conversion and how it depends on the acoustic conditions and droplet physical parameters. Lipid-encapsulated droplets containing dodecafluoropentane were manufactured with sizes ranging from 1.9 to 7.2 {mu}m in diameter and diluted to a concentration of 8 x 10{sup 6} droplets mL{sup -1}. The droplets were sonicated in vitro with a focused ultrasound transducer and varying frequency and exposure under flow conditions through an acoustically transparent vessel. The sonications were 10 ms in duration at frequencies of 0.578, 1.736 and 2.855 MHz. The pressure threshold for droplet conversion was measured with an active transducer operating in pulse-echo mode and simultaneous measurements of broadband acoustic emissions were performed with passive acoustic detection. The results show that droplets cannot be converted at low frequency without broadband emissions occurring. However, the pressure threshold for droplet conversion decreased with increasing frequency, exposure and droplet size. The pressure threshold for broadband emissions was independent of the droplet size and was 2.9, 4.4 and 5.3 MPa for 0.578, 1736 and 2.855 MHz, respectively. In summary, we have demonstrated that droplet conversion is feasible for clinically relevant sized droplets and acoustic exposures.

  8. In vitro characterization of perfluorocarbon droplets for focused ultrasound therapy

    International Nuclear Information System (INIS)

    Schad, Kelly C; Hynynen, Kullervo

    2010-01-01

    Focused ultrasound therapy can be enhanced with microbubbles by thermal and cavitation effects. However, localization of treatment is difficult as bioeffects can occur outside of the target region. Spatial control of bubbles can be achieved by ultrasound-induced conversion of liquid perfluorocarbon droplets to gas bubbles. This study was undertaken to determine the acoustic parameters for bubble production by droplet conversion and how it depends on the acoustic conditions and droplet physical parameters. Lipid-encapsulated droplets containing dodecafluoropentane were manufactured with sizes ranging from 1.9 to 7.2 μm in diameter and diluted to a concentration of 8 x 10 6 droplets mL -1 . The droplets were sonicated in vitro with a focused ultrasound transducer and varying frequency and exposure under flow conditions through an acoustically transparent vessel. The sonications were 10 ms in duration at frequencies of 0.578, 1.736 and 2.855 MHz. The pressure threshold for droplet conversion was measured with an active transducer operating in pulse-echo mode and simultaneous measurements of broadband acoustic emissions were performed with passive acoustic detection. The results show that droplets cannot be converted at low frequency without broadband emissions occurring. However, the pressure threshold for droplet conversion decreased with increasing frequency, exposure and droplet size. The pressure threshold for broadband emissions was independent of the droplet size and was 2.9, 4.4 and 5.3 MPa for 0.578, 1736 and 2.855 MHz, respectively. In summary, we have demonstrated that droplet conversion is feasible for clinically relevant sized droplets and acoustic exposures.

  9. In vitro characterization of perfluorocarbon droplets for focused ultrasound therapy

    Science.gov (United States)

    Schad, Kelly C.; Hynynen, Kullervo

    2010-09-01

    Focused ultrasound therapy can be enhanced with microbubbles by thermal and cavitation effects. However, localization of treatment is difficult as bioeffects can occur outside of the target region. Spatial control of bubbles can be achieved by ultrasound-induced conversion of liquid perfluorocarbon droplets to gas bubbles. This study was undertaken to determine the acoustic parameters for bubble production by droplet conversion and how it depends on the acoustic conditions and droplet physical parameters. Lipid-encapsulated droplets containing dodecafluoropentane were manufactured with sizes ranging from 1.9 to 7.2 µm in diameter and diluted to a concentration of 8 × 106 droplets mL-1. The droplets were sonicated in vitro with a focused ultrasound transducer and varying frequency and exposure under flow conditions through an acoustically transparent vessel. The sonications were 10 ms in duration at frequencies of 0.578, 1.736 and 2.855 MHz. The pressure threshold for droplet conversion was measured with an active transducer operating in pulse-echo mode and simultaneous measurements of broadband acoustic emissions were performed with passive acoustic detection. The results show that droplets cannot be converted at low frequency without broadband emissions occurring. However, the pressure threshold for droplet conversion decreased with increasing frequency, exposure and droplet size. The pressure threshold for broadband emissions was independent of the droplet size and was 2.9, 4.4 and 5.3 MPa for 0.578, 1736 and 2.855 MHz, respectively. In summary, we have demonstrated that droplet conversion is feasible for clinically relevant sized droplets and acoustic exposures.

  10. Pulmonary Vein Isolation by High Intensity Focused Ultrasound

    Directory of Open Access Journals (Sweden)

    Matthias Antz

    2007-04-01

    Full Text Available Pulmonary vein isolation (PVI using radiofrequency current (RFC ablation is a potentially curative treatment option for patients with atrial fibrillation (AF. The shortcomings of the RFC technology (technically challenging, long procedure times, complications steadily kindle the interest in new energy sources and catheter designs. High intensity focused ultrasound (HIFU has the ability to precisely focus ultrasound waves in a defined area with a high energy density. HIFU balloon catheters (BC positioned at the PV ostia appear to be an ideal tool to transmit the ablation energy in a circumferential manner to the PV ostia and may therefore bear substantial advantage over conventional ablation catheters in PVI procedures. In clinical trials the HIFU BC has shown promising success rates similar to RFC catheter ablation for PVI in patients with AF. However, procedure times are still long and serious complications have been observed. Therefore, it may be a valuable alternative to the conventional techniques in selected patients but further clinical trials have to be initiated.

  11. Gaussian representation of high-intensity focused ultrasound beams.

    Science.gov (United States)

    Soneson, Joshua E; Myers, Matthew R

    2007-11-01

    A method for fast numerical simulation of high-intensity focused ultrasound beams is derived. The method is based on the frequency-domain representation of the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, and assumes for each harmonic a Gaussian transverse pressure distribution at all distances from the transducer face. The beamwidths of the harmonics are constrained to vary inversely with the square root of the harmonic number, and as such this method may be viewed as an extension of a quasilinear approximation. The technique is capable of determining pressure or intensity fields of moderately nonlinear high-intensity focused ultrasound beams in water or biological tissue, usually requiring less than a minute of computer time on a modern workstation. Moreover, this method is particularly well suited to high-gain simulations since, unlike traditional finite-difference methods, it is not subject to resolution limitations in the transverse direction. Results are shown to be in reasonable agreement with numerical solutions of the full KZK equation in both tissue and water for moderately nonlinear beams.

  12. Ultrasound-guided genitourinary interventions: principles and techniques

    Directory of Open Access Journals (Sweden)

    Byung Kwan Park

    2017-10-01

    Full Text Available Ultrasound (US is often used to guide various interventional procedures in the genitourinary (GU tract because it can provide real-time imaging without any radiation hazard. Moreover, US can clearly visualize the pathway of an aspiration or biopsy needle to ensure the safety of the intervention. US guidance also helps clinicians to access lesions via the transabdominal, transhepatic, transvaginal, transrectal, and transperineal routes. Hence, US-guided procedures are useful for radiologists who wish to perform GU interventions. However, US-guided procedures and interventions are difficult for beginners because they involve a steep initial learning curve. The purpose of this review is to describe the basic principles and techniques of US-guided GU interventions.

  13. An ultrasound needle insertion guide in a porcine phantom model.

    Science.gov (United States)

    Whittaker, S; Lethbridge, G; Kim, C; Keon Cohen, Z; Ng, I

    2013-08-01

    We compared nerve blockade with and without the Infiniti(TM) needle guide in an ultrasound in-plane porcine simulation. We recruited 30 anaesthetists with varying blockade experience. Using the guide, the needle tip was more visible (for a median (IQR [range]) of 67 (56-100]) % of the time; and invisible for 2 (1-4 [0-19]) s) than when the guide was not used (respectively 23 (13-43 [0-80]) % and 25 (9-52 [1-198]) s; both p < 0.001). The corresponding block times were 8 (6-10 [3-28]) s and 32 (15-67 [5-225]) s, respectively; p < 0.001. The needle guide reduced the block time and the time that the needle was invisible, irrespective of anaesthetist experience. Anaesthesia © 2013 The Association of Anaesthetists of Great Britain and Ireland.

  14. Ultrasound-guided genitourinary interventions: principles and techniques

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Kwan [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2017-10-15

    Ultrasound (US) is often used to guide various interventional procedures in the genitourinary (GU) tract because it can provide real-time imaging without any radiation hazard. Moreover, US can clearly visualize the pathway of an aspiration or biopsy needle to ensure the safety of the intervention. US guidance also helps clinicians to access lesions via the transabdominal, transhepatic, transvaginal, transrectal, and transperineal routes. Hence, US-guided procedures are useful for radiologists who wish to perform GU interventions. However, US-guided procedures and interventions are difficult for beginners because they involve a steep initial learning curve. The purpose of this review is to describe the basic principles and techniques of US-guided GU interventions.

  15. Ultrasound-mediated Optical Imaging and Focusing in Scattering Media

    Science.gov (United States)

    Suzuki, Yuta

    Because of its non-ionizing and molecular sensing nature, light has been an attractive tool in biomedicine. Scanning an optical focus allows not only high-resolution imaging but also manipulation and therapy. However, due to multiple photon scattering events, conventional optical focusing using an ordinary lens is limited to shallow depths of one transport mean free path (lt'), which corresponds to approximately 1 mm in human tissue. To overcome this limitation, ultrasonic modulation (or encoding ) of diffuse light inside scattering media has enabled us to develop both deep-tissue optical imaging and focusing techniques, namely, ultrasound-modulated optical tomography (UOT) and time-reversed ultrasonically encoded (TRUE) optical focusing. While UOT measures the power of the encoded light to obtain an image, TRUE focusing generates a time-reversed (or phase-conjugated) copy of the encoded light, using a phase-conjugate mirror to focus light inside scattering media beyond 1 lt'. However, despite extensive progress in both UOT and TRUE focusing, the low signal-to-noise ratio in encoded-light detection remains a challenge to meeting both the speed and depth requirements for in vivo applications. This dissertation describes technological advancements of both UOT and TRUE focusing, in terms of their signal detection sensitivities, operational depths, and operational speeds. The first part of this dissertation describes sensitivity improvements of encoded-light detection in UOT, achieved by using a large area (˜5 cm x 5 cm) photorefractive polymer. The photorefractive polymer allowed us to improve the detection etendue by more than 10 times that of previous detection schemes. It has enabled us to resolve absorbing objects embedded inside diffused media thicker than 80 lt', using moderate light power and short ultrasound pulses. The second part of this dissertation describes energy enhancement and fluorescent excitation using TRUE focusing in turbid media, using

  16. Faculty staff-guided versus self-guided ultrasound training for internal medicine residents.

    Science.gov (United States)

    Alba, George A; Kelmenson, Daniel A; Noble, Vicki E; Murray, Alice F; Currier, Paul F

    2013-11-01

    Ultrasonography is of growing importance within internal medicine (IM), but the optimal method of training doctors to use it is uncertain. In this study, the authors provide the first objective comparison of two approaches to training IM residents in ultrasonography. In this randomised trial, a simulation-based ultrasound training curriculum was implemented during IM intern orientation at a tertiary care teaching hospital. All 72 incoming interns attended a lecture and were given access to online modules. Interns were then randomly assigned to a 4-hour faculty-guided (FG) or self-guided (SG) ultrasound training session in a simulation laboratory with both human and manikin models. Interns were asked to self-assess their competence in ultrasonography and underwent an objective structured clinical examination (OSCE) to assess their competence in basic and procedurally oriented ultrasound tasks. The primary outcome was the score on the OSCE. Faculty-guided training was superior to self-guided training based on the OSCE scores. Subjects in the FG training group achieved significantly higher OSCE scores on the two subsets of task completion (0.9-point difference, 95% confidence interval [CI] 0.27-1.54; p = 0.008) and ultrasound image quality (2.43-point difference, 95% CI 1.5-3.36; p training groups demonstrated an increase in self-assessed competence after their respective training sessions and there was little difference between the groups. Subjects rated the FG training group much more favourably than the SG training group. Both FG and SG ultrasound training curricula can improve the self-reported competence of IM interns in ultrasonography. However, FG training was superior to SG training in both skills acquisition and intern preference. Incorporating mandatory ultrasound training into IM residencies can address the perceived need for ultrasound training, improve confidence and procedural skills, and may enhance patient safety. However, the optimal training method

  17. Endoscopic ultrasound-guided transmural drainage of postoperative pancreatic collections.

    Science.gov (United States)

    Tilara, Amy; Gerdes, Hans; Allen, Peter; Jarnagin, William; Kingham, Peter; Fong, Yuman; DeMatteo, Ronald; D'Angelica, Michael; Schattner, Mark

    2014-01-01

    Pancreatic leak is a major cause of morbidity after pancreatectomy. Traditionally, peripancreatic fluid collections have been managed by percutaneous or operative drainage. Data for endoscopic ultrasound (EUS)-guided drainage of postoperative fluid collections are limited. Here we report on the safety, efficacy, and timing of EUS-guided drainage of postoperative peripancreatic collections. This is a retrospective review of 31 patients who underwent EUS-guided drainage of fluid collections after pancreatic resection. Technical success was defined as successful transgastric deployment of at least one double pigtail plastic stent. Clinical success was defined as resolution of the fluid collection on follow-up CT scan and resolution of symptoms. Early drainage was defined as initial transmural stent placement within 30 days after surgery. Endoscopic ultrasound-guided drainage was performed effectively with a technical success rate of 100%. Clinical success was achieved in 29 of 31 patients (93%). Nineteen of the 29 patients (65%) had complete resolution of their symptoms and collection with the first endoscopic procedure. Repeat drainage procedures, including some with necrosectomy, were required in the remaining 10 patients, with eventual resolution of collection and symptoms. Two patients who did not achieve durable clinical success required percutaneous drainage by interventional radiology. Seventeen (55%) of 31 patients had successful early drainage completed within 30 days of their operation. Endoscopic ultrasound-guided drainage of fluid collections after pancreatic resection is safe and effective. Early drainage (collections was not associated with increased complications in this series. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  18. Ultrasound-guided peripheral and truncal blocks in pediatric patients

    Directory of Open Access Journals (Sweden)

    Mohamed Bilal Delvi

    2011-01-01

    Full Text Available Ultrasound has added a feather in the cap of the anesthesiologists as real-time nerve localization and drug deposition around the nerve structure under real-time guidance is now a reality, as the saying "seeing is believing" has been proven true with the advent of ultrasound in anesthesia. Pediatric patients are a unique group regarding their anatomical and physiological features in comparison with adults; regional blocks in adults with the anatomical landmark and surface marking are almost uniform across the adult population. The landmark technique in pediatric patients is not reliable in all patients due to the variability in the age and size; the advent of ultrasound in assisting nerve localization has changed the way regional blocks are achieved in children and the range of blocks performed on adults can now be performed on pediatric patients; with advances in the technology and dexterity of ultrasound equipment, the chances of success of blocks has increased with a smaller dose of the local anesthetic in comparison to the traditional methods. Anesthesiologists are now able to perform blocks with more accuracy and avoid complications like intravascular injection and injury to the pleura and peritoneum during routine practice with the assistance of high-frequency transducers and top of the range portable ultrasound machines; catheters can be inserted to provide a continuous analgesia in the postoperative period. This review article describes the common peripheral blocks in pediatric patients; the readers are encouraged to gain experience by attending workshops, hands-on practice under supervision, and conduct random controlled trials pertaining to ultrasound-guided blocks in the pediatric age group. The recent literature is encouraging and further research is promising; a wide range of blocks being described in detail by many prominent experts from all over the world.

  19. Noninvasive transcranial stimulation of rat abducens nerve by focused ultrasound.

    Science.gov (United States)

    Kim, Hyungmin; Taghados, Seyed Javid; Fischer, Krisztina; Maeng, Lee-So; Park, Shinsuk; Yoo, Seung-Schik

    2012-09-01

    Nonpharmacologic and nonsurgical transcranial modulation of the nerve function may provide new opportunities in evaluation and treatment of cranial nerve diseases. This study investigates the possibility of using low-intensity transcranial focused ultrasound (FUS) to selectively stimulate the rat abducens nerve located above the base of the skull. FUS (frequencies of 350 kHz and 650 kHz) operating in a pulsed mode was applied to the abducens nerve of Sprague-Dawley rats under stereotactic guidance. The abductive eyeball movement ipsilateral to the side of sonication was observed at 350 kHz, using the 0.36-msec tone burst duration (TBD), 1.5-kHz pulse repetition frequency (PRF), and the overall sonication duration of 200 msec. Histologic and behavioral monitoring showed no signs of disruption in the blood brain barrier (BBB), as well as no damage to the nerves and adjacent brain tissue resulting from the sonication. As a novel functional neuro-modulatory modality, the pulsed application of FUS has potential for diagnostic and therapeutic applications in diseases of the peripheral nervous system. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  20. WE-H-209-00: Carson/Zagzebski Distinguished Lectureship: Image Guided Ultrasound Therapy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    Focused ultrasound has been shown to be the only method that allows noninvasive thermal coagulation of tissues and recently this potential has been explored for image-guided drug delivery. In this presentation, the advances in ultrasound phased array technology for energy delivery, exposure monitoring and control will be discussed. Experimental results from novel multi-frequency transmit/receive arrays will be presented. In addition, the feasibility of fully electronically focused and steered high power arrays with many thousands of transducer elements will be discussed. Finally, some of the recent clinical and preclinical results for the treatment of brain disease will be reviewed. Learning Objectives: Introduce FUS therapy principles and modern techniques Discuss use of FUS for drug delivery Cover the technology required to deliver FUS and monitor therapy Present clinical examples of the uses of these techniques This research was supported by funding from The Canada Research Chair Program, Grants from CIHR and NIH (no. EB003268).; K. Hynynen, Canada Foundation for Innovation; Canadian Institutes of Health Research; Focused Ultrasound Surgery Foundation; Canada Research Chair Program; Natural Sciences and Engineering Research Council of Canada; Ontario Research Fund; National Institutes of Health; Canadian Cancer Society Research Institute; The Weston Brain Institute; Harmonic Medical; Focused Ultrasound Instruments.

  1. High-intensity focused ultrasound treatment of placenta accreta after vaginal delivery: a preliminary study.

    Science.gov (United States)

    Bai, Y; Luo, X; Li, Q; Yin, N; Fu, X; Zhang, H; Qi, H

    2016-04-01

    To evaluate the safety and efficiency of high-intensity focused ultrasound (HIFU) in the treatment of placenta accreta after vaginal delivery. Enrolled into this study between September 2011 and September 2013 were 12 patients who had been diagnosed with placenta accreta following vaginal delivery and who had stable vital signs. All patients were treated using an ultrasound-guided HIFU treatment system. As indication of the effectiveness of the treatment we considered decreased vascular index on color Doppler imaging, decrease in size of residual placenta compared with pretreatment size on assessment by three-dimensional ultrasound with Virtual Organ Computer-aided Analysis, reduced signal intensity and degree of enhancement on magnetic resonance imaging and avoidance of hysterectomy following treatment. To assess the safety of HIFU treatment, we recorded side effects, hemorrhage, infection, sex steroid levels, return of menses and subsequent pregnancy. Patients were followed up in this preliminary study until December 2013. The 12 patients receiving HIFU treatment had an average postpartum hospital stay of 6.8 days and an average period of residual placental involution of 36.9 days. HIFU treatment did not apparently increase the risk of infection or hemorrhage and no patient required hysterectomy. In all patients menstruation recommenced after an average of 80.2 days, and sex steroid levels during the middle luteal phase of the second menstrual cycle were normal. Two patients became pregnant again during the follow-up period. This preliminary study suggests that ultrasound-guided HIFU is a safe and effective non-invasive method to treat placenta accreta patients after vaginal delivery who have stable vital signs and desire to preserve fertility. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

  2. A novel ultrasound-guided shoulder arthroscopic surgery

    Science.gov (United States)

    Tyryshkin, K.; Mousavi, P.; Beek, M.; Chen, T.; Pichora, D.; Abolmaesumi, P.

    2006-03-01

    This paper presents a novel ultrasound-guided computer system for arthroscopic surgery of the shoulder joint. Intraoperatively, the system tracks and displays the surgical instruments, such as arthroscope and arthroscopic burrs, relative to the anatomy of the patient. The purpose of this system is to improve the surgeon's perception of the three-dimensional space within the anatomy of the patient in which the instruments are manipulated and to provide guidance towards the targeted anatomy. Pre-operatively, computed tomography images of the patient are acquired to construct virtual threedimensional surface models of the shoulder bone structure. Intra-operatively, live ultrasound images of pre-selected regions of the shoulder are captured using an ultrasound probe whose three-dimensional position is tracked by an optical camera. These images are used to register the surface model to the anatomy of the patient in the operating room. An initial alignment is obtained by matching at least three points manually selected on the model to their corresponding points identified on the ultrasound images. The registration is then improved with an iterative closest point or a sequential least squares estimation technique. In the present study the registration results of these techniques are compared. After the registration, surgical instruments are displayed relative to the surface model of the patient on a graphical screen visible to the surgeon. Results of laboratory experiments on a shoulder phantom indicate acceptable registration results and sufficiently fast overall system performance to be applicable in the operating room.

  3. Ultrasound-guided percutaneous core needle biopsy of splenic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Park, SangIk; Shin, Yong Moon; Won, Hyung Jin; Kim, Pyo Nyun; Lee, Moon Gyu [Dept. of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2017-05-15

    To evaluate the safety and efficacy of ultrasound-guided percutaneous core needle biopsy of splenic lesions. This retrospective study included 30 patients who underwent percutaneous core needle biopsy of their splenic lesions using 18- or 20-gauge needles between January 2001 and July 2016 in a single tertiary care center. The characteristics of the splenic lesions were determined by reviewing the ultrasound and computed tomography examinations. Acquisition rate and diagnostic accuracy were calculated, using pathologic results of the splenectomy specimen, clinical course and/or imaging follow-up as a reference standard. Post-procedure complications were identified from electronic medical records, laboratory findings and computed tomography images. Seventy-three specimens were obtained from the 30 patients and splenectomy was performed in 2 patients. Twenty-nine of the 30 patients had focal splenic lesions, while the remaining patient had homogeneous splenomegaly. Acquisition rate and diagnostic accuracy were 80.0% (24/30) and 76.7% (23/30), respectively. Perisplenic hemorrhage without hemodynamic instability developed in one patient. Ultrasound-guided percutaneous core needle biopsy of splenic lesions is a safe method for achieving a histopathologic diagnosis and can be considered as an alternative to splenectomy in patients with a high risk of splenectomy-related complications.

  4. Ultrasound-guided percutaneous core needle biopsy of splenic lesions

    International Nuclear Information System (INIS)

    Park, SangIk; Shin, Yong Moon; Won, Hyung Jin; Kim, Pyo Nyun; Lee, Moon Gyu

    2017-01-01

    To evaluate the safety and efficacy of ultrasound-guided percutaneous core needle biopsy of splenic lesions. This retrospective study included 30 patients who underwent percutaneous core needle biopsy of their splenic lesions using 18- or 20-gauge needles between January 2001 and July 2016 in a single tertiary care center. The characteristics of the splenic lesions were determined by reviewing the ultrasound and computed tomography examinations. Acquisition rate and diagnostic accuracy were calculated, using pathologic results of the splenectomy specimen, clinical course and/or imaging follow-up as a reference standard. Post-procedure complications were identified from electronic medical records, laboratory findings and computed tomography images. Seventy-three specimens were obtained from the 30 patients and splenectomy was performed in 2 patients. Twenty-nine of the 30 patients had focal splenic lesions, while the remaining patient had homogeneous splenomegaly. Acquisition rate and diagnostic accuracy were 80.0% (24/30) and 76.7% (23/30), respectively. Perisplenic hemorrhage without hemodynamic instability developed in one patient. Ultrasound-guided percutaneous core needle biopsy of splenic lesions is a safe method for achieving a histopathologic diagnosis and can be considered as an alternative to splenectomy in patients with a high risk of splenectomy-related complications

  5. High-Intensity Focused Ultrasound Treatment for Advanced Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Yufeng Zhou

    2014-01-01

    Full Text Available Pancreatic cancer is under high mortality but has few effective treatment modalities. High-intensity focused ultrasound (HIFU is becoming an emerging approach of noninvasively ablating solid tumor in clinics. A variety of solid tumors have been tried on thousands of patients in the last fifteen years with great success. The principle, mechanism, and clinical outcome of HIFU were introduced first. All 3022 clinical cases of HIFU treatment for the advanced pancreatic cancer alone or in combination with chemotherapy or radiotherapy in 241 published papers were reviewed and summarized for its efficacy, pain relief, clinical benefit rate, survival, Karnofsky performance scale (KPS score, changes in tumor size, occurrence of echogenicity, serum level, diagnostic assessment of outcome, and associated complications. Immune response induced by HIFU ablation may become an effective way of cancer treatment. Comments for a better outcome and current challenges of HIFU technology are also covered.

  6. Ultrasound-Guided Regional Anesthesia Simulation Training: A Systematic Review.

    Science.gov (United States)

    Chen, Xiao Xu; Trivedi, Vatsal; AlSaflan, AbdulHadi A; Todd, Suzanne Clare; Tricco, Andrea C; McCartney, Colin J L; Boet, Sylvain

    Ultrasound-guided regional anesthesia (UGRA) has become the criterion standard of regional anesthesia practice. Ultrasound-guided regional anesthesia teaching programs often use simulation, and guidelines have been published to help guide URGA education. This systematic review aimed to examine the effectiveness of simulation-based education for the acquisition and maintenance of competence in UGRA. Studies identified in MEDLINE, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, and ERIC were included if they assessed simulation-based UGRA teaching with outcomes measured at Kirkpatrick level 2 (knowledge and skills), 3 (transfer of learning to the workplace), or 4 (patient outcomes). Two authors independently reviewed all identified references for eligibility, abstracted data, and appraised quality. After screening 176 citations and 45 full-text articles, 12 studies were included. Simulation-enhanced training improved knowledge acquisition (Kirkpatrick level 2) when compared with nonsimulation training. Seven studies measuring skill acquisition (Kirkpatrick level 2) found that simulation-enhanced UGRA training was significantly more effective than alternative teaching methods or no intervention. One study measuring transfer of learning into the clinical setting (Kirkpatrick level 3) found no difference between simulation-enhanced UGRA training and non-simulation-based training. However, this study was discontinued early because of technical challenges. Two studies examined patient outcomes (Kirkpatrick level 4), and one of these found that simulation-based UGRA training improved patient outcomes compared with didactic teaching. Ultrasound-guided regional anesthesia knowledge and skills significantly improved with simulation training. The acquired UGRA skills may be transferred to the clinical setting; however, further studies are required to confirm these changes translate to improved patient outcomes.

  7. Guided interventions in musculoskeletal ultrasound: what's the evidence?

    International Nuclear Information System (INIS)

    Davidson, J.; Jayaraman, S.

    2011-01-01

    Increasing histological and radiological understanding of the processes involved in soft-tissue injury is leading to novel targeted treatments. A number of reviews have recommended that these treatments should be performed with image guidance. This review describes current ultrasound-guided interventions and injections, together with the level of evidence for these. Discussion of guided interventions will include; percutaneous lavage (barbotage), brisement, dry needling, electrocoagulation, and of guided injections; corticosteroids, autologous substances (blood and platelet rich plasma), sclerosants, and prolotherapy (hyperosmolar dextrose). Representative imaging illustrating some of these techniques is included for correlation with the methods described. As these procedures are often performed in sportspeople, it is essential that the radiologist is aware of prohibited substances and methods outlined in an annual publication from the World Anti-Doping Association (WADA). Finally, future directions, including the use of autologous substances, mesenchymal and stem cells will be discussed.

  8. Ultrasound-guided injection for plantar fasciitis: A brief review

    Directory of Open Access Journals (Sweden)

    A S Nair

    2016-01-01

    Full Text Available Plantar fasciitis (PF is a distressing condition experienced by many patients. Although self-limiting, it tends to become a chronic ailment if the precipitating factors are not addressed. One of the modality of treating PF is intra-lesional corticosteroid injection. This was done using palpation technique earlier but nowadays many specialists use ultrasound (US imaging as a guide to give injection accurately instead of inadvertently damaging the plantar fascia or injecting into surrounding soft tissue, both of which can have serious implications. We did a literature search in Medline, Scopus, and Embase databases to find out articles describing US-guided corticosteroid injection for treating PF and whether guided injection was effective than injection given by palpation.

  9. Endoscopic ultrasound-guided radiofrequency ablation of the pancreas

    DEFF Research Database (Denmark)

    Silviu, Ungureanu Bogdan; Daniel, Pirici; Claudiu, Mărgăritescu

    2015-01-01

    ultrasound (EUS)-guided radiofrequency ablation (RFA) probe through a 19G needle in order to achieve a desirable necrosis area in the pancreas. Radiofrequency ablation of the head of the pancreas was performed on 10 Yorkshire pigs with a weight between 25 kg and 35 kg and a length of 40-70 cm. Using an EUS...... analysis revealed increased values of amylase, alkaline phosphatase, and gamma-glutamyl transpeptidase on the 3rd day but a decrease on the 5th day. After necropsy and isolation of the pancreas, the ablated area was easily found, describing a solid necrosis. The pathological examination revealed...

  10. Transcranial focused ultrasound stimulation of human primary visual cortex

    Science.gov (United States)

    Lee, Wonhye; Kim, Hyun-Chul; Jung, Yujin; Chung, Yong An; Song, In-Uk; Lee, Jong-Hwan; Yoo, Seung-Schik

    2016-09-01

    Transcranial focused ultrasound (FUS) is making progress as a new non-invasive mode of regional brain stimulation. Current evidence of FUS-mediated neurostimulation for humans has been limited to the observation of subjective sensory manifestations and electrophysiological responses, thus warranting the identification of stimulated brain regions. Here, we report FUS sonication of the primary visual cortex (V1) in humans, resulting in elicited activation not only from the sonicated brain area, but also from the network of regions involved in visual and higher-order cognitive processes (as revealed by simultaneous acquisition of blood-oxygenation-level-dependent functional magnetic resonance imaging). Accompanying phosphene perception was also reported. The electroencephalo graphic (EEG) responses showed distinct peaks associated with the stimulation. None of the participants showed any adverse effects from the sonication based on neuroimaging and neurological examinations. Retrospective numerical simulation of the acoustic profile showed the presence of individual variability in terms of the location and intensity of the acoustic focus. With exquisite spatial selectivity and capability for depth penetration, FUS may confer a unique utility in providing non-invasive stimulation of region-specific brain circuits for neuroscientific and therapeutic applications.

  11. MO-AB-210-03: Workshop [Advancements in high intensity focused ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Z. [University of Chicago (United States)

    2015-06-15

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  12. Models to teach lung sonopathology and ultrasound-guided thoracentesis

    Directory of Open Access Journals (Sweden)

    Jacek A. Wojtczak

    2014-12-01

    Full Text Available Lung sonography allows rapid diagnosis of lung emergencies such as pulmonary edema, hemothorax or pneumothorax. The ability to timely diagnose an intraoperative pneumothorax is an important skill for the anesthesiologist. However, lung ultrasound exams require an interpretation of not only real images but also complex acoustic artifacts such as A-lines and B-lines. Therefore, appropriate training to gain proficiency is important. Simulated environment using ultrasound phantom models allows controlled, supervised learning. We have developed hybrid models that combine dry or wet polyurethane foams, porcine rib cages and human hand simulating a rib cage. These models simulate fairly accurately pulmonary sonopathology and allow supervised teaching of lung sonography with the immediate feedback. In-vitro models can also facilitate learning of procedural skills, improving transducer and needle positioning and movement, rapid recognition of thoracic anatomy and hand – eye coordination skills. We described a new model to teach an ultrasound guided thoracentesis. This model consists of the experimenter’s hand placed on top of the water-filled container with a wet foam. Metacarpal bones of the human hand simulate a rib cage and a wet foam simulates a diseased lung immersed in the pleural fluid. Positive fluid flow offers users feedback when a simulated pleural effusion is accurately assessed.

  13. High-intensity focused ultrasound ablation around the tubing.

    Science.gov (United States)

    Siu, Jun Yang; Liu, Chenhui; Zhou, Yufeng

    2017-01-01

    High-intensity focused ultrasound (HIFU) has been emerging as an effective and noninvasive modality in cancer treatment with very promising clinical results. However, a small vessel in the focal region could be ruptured, which is an important concern for the safety of HIFU ablation. In this study, lesion formation in the polyacrylamide gel phantom embedded with different tubing (inner diameters of 0.76 mm and 3 mm) at varied flow speeds (17-339 cm/s) by HIFU ablation was photographically recorded. Produced lesions have decreased length (~30%) but slightly increased width (~6%) in comparison to that without the embedded tubing. Meanwhile, bubble activities during the exposures were measured by passive cavitation detection (PCD) at the varied pulse repetition frequency (PRF, 10-30 Hz) and duty cycle (DC, 10%-20%) of the HIFU bursts. High DC and low flow speed were found to produce stronger bubble cavitation whereas no significant influence of the PRF. In addition, high-speed photography illustrated that the rupture of tubing was produced consistently after the first HIFU burst within 20 ms and then multiple bubbles would penetrate into the intraluminal space of tubing through the rupture site by the acoustic radiation force. Alignment of HIFU focus to the anterior surface, middle, and posterior surface of tubing led to different characteristics of vessel rupture and bubble introduction. In summary, HIFU-induced vessel rupture is possible as shown in this phantom study; produced lesion sizes and shapes are dependent on the focus alignment to the tubing, flow speed, and tubing properties; and bubble cavitation and the formation liquid jet may be one of the major mechanisms of tubing rupture as shown in the high-speed photography.

  14. Localizing and Assessing Amputee Pain with Intense Focused Ultrasound

    Science.gov (United States)

    2016-10-01

    active ultrasound images the target of iFU stimulation. Ultrasound device – integrated ig-iFU system. The imaging transducer was mounted within a...meditation, spinal cord stimulation, psychotherapy , continued watchful waiting, among other choices (28). Future research Future studies might consider

  15. Gelatin model for training ultrasound-guided puncture

    Directory of Open Access Journals (Sweden)

    Alexandre Campos Moraes Amato

    2015-09-01

    Full Text Available BACKGROUND: It is indispensable that members of the medical profession receive the technical training needed to enable them to rapidly obtain effective vascular access. Training procedures should be used judiciously to familiarize students with the technique. However, existing models are expensive or ineffective, and models need to be developed that are similar to what will be encountered in real patients.OBJECTIVES: To demonstrate creation and application of a gelatin model for training ultrasound-guided puncture.METHOS: The model was made using a mixture of colorless gelatin and water in a transparent plastic receptacle with two pairs of orifices of different diameters, through which two plastic tubes were inserted, to simulate blood vessels.RESULTS: The model was a close approximation to the real medical procedure in several aspects, since gelatin has a similar consistency to human tissues, providing a more faithful reproduction of the tactile sensation at the moment when the needle reaches the interior of a vessel and its contents are aspirated.CONCLUSIONS: The method proposed here can be used to easily construct a low-cost model using everyday materials that is suitable for large-scale training of ultrasound-guided puncture.

  16. Multifunctional pulse generator for high-intensity focused ultrasound system

    Science.gov (United States)

    Tamano, Satoshi; Yoshizawa, Shin; Umemura, Shin-Ichiro

    2017-07-01

    High-intensity focused ultrasound (HIFU) can achieve high spatial resolution for the treatment of diseases. A major technical challenge in implementing a HIFU therapeutic system is to generate high-voltage high-current signals for effectively exciting a multichannel HIFU transducer at high efficiencies. In this paper, we present the development of a multifunctional multichannel generator/driver. The generator can produce a long burst as well as an extremely high-voltage short pulse of pseudosinusoidal waves (trigger HIFU) and second-harmonic superimposed waves for HIFU transmission. The transmission timing, waveform, and frequency can be controlled using a field-programmable gate array (FPGA) via a universal serial bus (USB) microcontroller. The hardware is implemented in a compact printed circuit board. The test results of trigger HIFU reveal that the power consumption and the temperature rise of metal-oxide semiconductor field-effect transistors were reduced by 19.9% and 38.2 °C, respectively, from the previous design. The highly flexible performance of the novel generator/driver is demonstrated in the generation of second-harmonic superimposed waves, which is useful for cavitation-enhanced HIFU treatment, although the previous design exhibited difficulty in generating it.

  17. Robotic Assisted Laparoscopic Prostatectomy after High Intensity Focused Ultrasound Failure

    Directory of Open Access Journals (Sweden)

    Leon Telis

    2017-01-01

    Full Text Available Background. Prostate cancer is the most common cancer diagnosed in men. As new focal therapies become more popular in treatment of prostate cancer, failure cases requiring salvage therapy with either surgical or other techniques are being reported. Objective. To report the options in treatment of prostate cancer after recurrence or failure of the primary treatment modality. Methods. We report a salvage robotic assisted laparoscopic radical prostatectomy (RALP for prostate cancer recurrence following high intensity focused ultrasound treatment (HIFU in the United States. Results. A 67-year-old man who underwent HIFU treatment for prostate adenocarcinoma 2 years prior was presented with a rising prostate specific antigen of 6.1 ng/mL to our clinic. A biopsy proven recurrent disease in the area of previous treatment documented the failure of treatment. The patient elected to undergo a salvage RALP. The operation time was 159 minutes. The patient was discharged from the hospital on postoperative day 1 with no complications. The catheter was removed on post-op day 10. The patient reserved sexual function and urinary continence. The PSA levels on 6 months’ follow-up are undetectable. Conclusions. Salvage RALP is an effective and safe treatment choice for recurrent prostate adenocarcinoma following failed HIFU treatment if operated by an experienced surgeon.

  18. Microwave ablation of liver metastases guided by contrast-enhanced ultrasound

    DEFF Research Database (Denmark)

    Lorentzen, T; Skjoldbye, B O; Nolsoe, C P

    2011-01-01

    The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS).......The aim of our study was to evaluate the efficacy of microwave (MW) ablation of liver metastases guided by B-mode ultrasound (US) and contrast-enhanced US (CEUS)....

  19. Ultrasound-guided drainage of subcutaneous abscesses on the trunk is feasible

    DEFF Research Database (Denmark)

    Kjær, Søren; Rud, Bo; Bay-Nielsen, Morten

    2013-01-01

    Subcutaneous trunk abscesses are frequent, and current treatment options generally involve incision. By contrast, the standard care for breast abcesses is ultrasound-guided drainage. The aim of this study was to evaluate the feasibility of ultrasound-guided drainage combined with antibiotics...... in the treatment of subcutaneous abscesses on the trunk....

  20. Technical tips to perform safe and effective ultrasound guided steroid joint injections in children.

    Science.gov (United States)

    Parra, Dimitri A

    2015-01-01

    The aim of this article is to describe the technique used to perform ultrasound guided steroid joint injections in children in a group of joints that can be injected using ultrasound as the only image guidance modality. The technique is described and didactic figures are provided to illustrate key technical concepts. It is very important to be familiar with the sonographic appearance of the pediatric joints and the developing bone when performing ultrasound-guided joint injections in children.

  1. Transvaginal Ultrasound-Guided Biopsy of Deep Pelvic Masses: How We Do It.

    Science.gov (United States)

    Plett, Sara K; Poder, Liina; Brooks, Rebecca A; Morgan, Tara A

    2016-06-01

    The purpose of this review is to discuss the rationale and indications for transvaginal ultrasound-guided biopsy. Transvaginal ultrasound-guided biopsy can be a helpful tool for diagnosis and treatment planning in the evaluation of pelvic masses, particularly when the anatomy precludes a transabdominal or posterior transgluteal percutaneous biopsy approach. A step-by-step summary of the technique with preprocedure and postprocedure considerations is included. © 2016 by the American Institute of Ultrasound in Medicine.

  2. Low-pressure pulsed focused ultrasound with microbubbles promotes an anticancer immunological response.

    Science.gov (United States)

    Liu, Hao-Li; Hsieh, Han-Yi; Lu, Li-An; Kang, Chiao-Wen; Wu, Ming-Fang; Lin, Chun-Yen

    2012-11-11

    High-intensity focused-ultrasound (HIFU) has been successfully employed for thermal ablation of tumors in clinical settings. Continuous- or pulsed-mode HIFU may also induce a host antitumor immune response, mainly through expansion of antigen-presenting cells in response to increased cellular debris and through increased macrophage activation/infiltration. Here we demonstrated that another form of focused ultrasound delivery, using low-pressure, pulsed-mode exposure in the presence of microbubbles (MBs), may also trigger an antitumor immunological response and inhibit tumor growth. A total of 280 tumor-bearing animals were subjected to sonographically-guided FUS. Implanted tumors were exposed to low-pressure FUS (0.6 to 1.4 MPa) with MBs to increase the permeability of tumor microvasculature. Tumor progression was suppressed by both 0.6 and 1.4-MPa MB-enhanced FUS exposures. We observed a transient increase in infiltration of non-T regulatory (non-Treg) tumor infiltrating lymphocytes (TILs) and continual infiltration of CD8+ cytotoxic T-lymphocytes (CTL). The ratio of CD8+/Treg increased significantly and tumor growth was inhibited. Our findings suggest that low-pressure FUS exposure with MBs may constitute a useful tool for triggering an anticancer immune response, for potential cancer immunotherapy.

  3. In vivo photoacoustics and high frequency ultrasound imaging of mechanical high intensity focused ultrasound (HIFU) ablation.

    Science.gov (United States)

    Daoudi, Khalid; Hoogenboom, Martijn; den Brok, Martijn; Eikelenboom, Dylan; Adema, Gosse J; Fütterer, Jürgen J; de Korte, Chris L

    2017-04-01

    The thermal effect of high intensity focused ultrasound (HIFU) has been clinically exploited over a decade, while the mechanical HIFU is still largely confined to laboratory investigations. This is in part due to the lack of adequate imaging techniques to better understand the in-vivo pathological and immunological effects caused by the mechanical treatment. In this work, we explore the use of high frequency ultrasound (US) and photoacoustics (PA) as a potential tool to evaluate the effect of mechanical ablation in-vivo , e.g. boiling histotripsy. Two mice bearing a neuroblastoma tumor in the right leg were ablated using an MRI-HIFU system conceived for small animals and monitored using MRI thermometry. High frequency US and PA imaging were performed before and after the HIFU treatment. Afterwards, the tumor was resected for further assessment and evaluation of the ablated region using histopathology. High frequency US imaging revealed the presence of liquefied regions in the treated area together with fragmentized tissue which appeared with different reflecting proprieties compared to the surrounding tissue. Photoacoustic imaging on the other hand revealed the presence of deoxygenated blood within the tumor after the ablation due to the destruction of blood vessel network while color Doppler imaging confirmed the blood vessel network destruction within the tumor. The treated area and the presence of red blood cells detected by photoacoustics were further confirmed by the histopathology. This feasibility study demonstrates the potential of high frequency US and PA approach for assessing in-vivo the effect of mechanical HIFU tumor ablation.

  4. Ultrasound image based visual servoing for moving target ablation by high intensity focused ultrasound.

    Science.gov (United States)

    Seo, Joonho; Koizumi, Norihiro; Mitsuishi, Mamoru; Sugita, Naohiko

    2017-12-01

    Although high intensity focused ultrasound (HIFU) is a promising technology for tumor treatment, a moving abdominal target is still a challenge in current HIFU systems. In particular, respiratory-induced organ motion can reduce the treatment efficiency and negatively influence the treatment result. In this research, we present: (1) a methodology for integration of ultrasound (US) image based visual servoing in a HIFU system; and (2) the experimental results obtained using the developed system. In the visual servoing system, target motion is monitored by biplane US imaging and tracked in real time (40 Hz) by registration with a preoperative 3D model. The distance between the target and the current HIFU focal position is calculated in every US frame and a three-axis robot physically compensates for differences. Because simultaneous HIFU irradiation disturbs US target imaging, a sophisticated interlacing strategy was constructed. In the experiments, respiratory-induced organ motion was simulated in a water tank with a linear actuator and kidney-shaped phantom model. Motion compensation with HIFU irradiation was applied to the moving phantom model. Based on the experimental results, visual servoing exhibited a motion compensation accuracy of 1.7 mm (RMS) on average. Moreover, the integrated system could make a spherical HIFU-ablated lesion in the desired position of the respiratory-moving phantom model. We have demonstrated the feasibility of our US image based visual servoing technique in a HIFU system for moving target treatment. © 2016 The Authors The International Journal of Medical Robotics and Computer Assisted Surgery Published by John Wiley & Sons Ltd.

  5. Hyperecho in ultrasound images during high-intensity focused ultrasound ablation for hepatocellular carcinomas

    International Nuclear Information System (INIS)

    Fukuda, Hiroyuki; Numata, Kazushi; Nozaki, Akito; Kondo, Masaaki; Morimoto, Manabu; Tanaka, Katsuaki; Ito, Ryu; Ohto, Masao; Ishibashi, Yoshiharu; Oshima, Noriyoshi; Ito, Ayao; Zhu, Hui; Wang Zhibiao

    2011-01-01

    High-intensity focused ultrasound (HIFU) is a noninvasive method that can cause complete coagulation necrosis without requiring the insertion of any instruments. The hyperechoic grayscale change (hyperechoic region) is used as a sign that the treated lesion has been completely coagulated. The purpose of this study was to evaluate the first hyperechoic region during treatment using HIFU ablation according to various conditions, such as the sonication power, the depth of the tumor from the surface of the skin, and the shield rate. HIFU treatment was performed in 20 patients. The HIFU system (Chongqing Haifu Tech, Chongqing, China) was used under ultrasound guidance. Complete coagulation was achieved in 17 cases. Hyperechoic region were detected after HIFU ablation in 17 patients. The size of the hyperechoic region at a depth of >50 mm was significantly smaller than that at a depth of ≤50 mm. The number and power of the sonications for areas at a depth of >50 mm were significantly larger than those for areas at a depth of ≤50 mm. The number and power in cases with a shield rate of 31–60% were significantly larger than those in cases with a shield rate of 0–30%. When the shield rate was 0%, a hyperechoic region occurred, even when a maximum sonication power was not used. In all three cases with tumors located at a depth of greater than 70 mm and a shield rate of larger than 60%, a hyperechoic region was not seen. In conclusion, hyperechoic regions are easy to visualize in cases with tumors located at a depth of ≤50 mm or shield rates of 0–30%.

  6. Image-guided ultrasound phased arrays are a disruptive technology for non-invasive therapy.

    Science.gov (United States)

    Hynynen, Kullervo; Jones, Ryan M

    2016-09-07

    Focused ultrasound offers a non-invasive way of depositing acoustic energy deep into the body, which can be harnessed for a broad spectrum of therapeutic purposes, including tissue ablation, the targeting of therapeutic agents, and stem cell delivery. Phased array transducers enable electronic control over the beam geometry and direction, and can be tailored to provide optimal energy deposition patterns for a given therapeutic application. Their use in combination with modern medical imaging for therapy guidance allows precise targeting, online monitoring, and post-treatment evaluation of the ultrasound-mediated bioeffects. In the past there have been some technical obstacles hindering the construction of large aperture, high-power, densely-populated phased arrays and, as a result, they have not been fully exploited for therapy delivery to date. However, recent research has made the construction of such arrays feasible, and it is expected that their continued development will both greatly improve the safety and efficacy of existing ultrasound therapies as well as enable treatments that are not currently possible with existing technology. This review will summarize the basic principles, current statures, and future potential of image-guided ultrasound phased arrays for therapy.

  7. Improving needle tip identification during ultrasound-guided procedures in anaesthetic practice.

    Science.gov (United States)

    Scholten, H J; Pourtaherian, A; Mihajlovic, N; Korsten, H H M; A Bouwman, R

    2017-07-01

    Ultrasound guidance is becoming standard practice for needle-based interventions in anaesthetic practice, such as vascular access and peripheral nerve blocks. However, difficulties in aligning the needle and the transducer can lead to incorrect identification of the needle tip, possibly damaging structures not visible on the ultrasound screen. Additional techniques specifically developed to aid alignment of needle and probe or identification of the needle tip are now available. In this scoping review, advantages and limitations of the following categories of those solutions are presented: needle guides; alterations to needle or needle tip; three- and four-dimensional ultrasound; magnetism, electromagnetic or GPS systems; optical tracking; augmented (virtual) reality; robotic assistance; and automated (computerised) needle detection. Most evidence originates from phantom studies, case reports and series, with few randomised clinical trials. Improved first-pass success and reduced performance time are the most frequently cited benefits, whereas the need for additional and often expensive hardware is the greatest limitation to widespread adoption. Novice ultrasound users seem to benefit most and great potential lies in education. Future research should focus on reporting relevant clinical parameters to learn which technique will benefit patients most in terms of success and safety. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

  8. Development of a High Intensity Focused Ultrasound (HIFU) Hydrophone System

    International Nuclear Information System (INIS)

    Schafer, Mark E.; Gessert, James

    2009-01-01

    The growing clinical use of High Intensity Focused Ultrasound (HIFU) has driven a need for reliable, reproducible measurements of HIFU acoustic fields. We have previously presented data on a reflective scatterer approach, incorporating several novel features for improved bandwidth, reliability, and reproducibility [Proc. 2005 IEEE Ultrasonics Symposium, 1739-1742]. We now report on several design improvements which have increase the signal to noise ratio of the system, and potentially reduced the cost of implementation. For the scattering element, we now use an artificial sapphire material to provide a more uniform radiating surface. The receiver is a segmented, truncated spherical structure with a 10 cm radius; the scattering element is positioned at the center of the sphere. The receiver is made from 25 micron thick, biaxially stretched PVDF, with a Pt-Au electrode on the front surface. In the new design, a specialized backing material provides the stiffness required to maintain structural stability, while at the same time providing both electrical shielding and ultrasonic absorption. Compared with the previous version, the new receiver design has improved the noise performance by 8-12 dB; the new scattering sphere has reduced the scattering loss by another 14 dB, producing an effective sensitivity of -298 dB re 1 microVolt/Pa. The design trade-off still involves receiver sensitivity with effective spot size, and signal distortion from the scatter structure. However, the reduced cost and improved repeatability of the new scatter approach makes the overall design more robust for routine waveform measurements of HIFU systems.

  9. Prostate Ultrasound

    Medline Plus

    Full Text Available ... ultrasound or with a rectal examination, an ultrasound-guided biopsy can be performed. This procedure involves advancing ... of the Prostate) Prostate Cancer Ultrasound- and MRI-Guided Prostate Biopsy Images related to Ultrasound - Prostate Sponsored ...

  10. Evaluation of ultrasound-guided vascular access in dogs.

    Science.gov (United States)

    Chamberlin, Scott C; Sullivan, Lauren A; Morley, Paul S; Boscan, Pedro

    2013-01-01

    To describe the technique and determine the feasibility, success rate, perceived difficulty, and time to vascular access using ultrasound guidance for jugular vein catheterization in a cardiac arrest dog model. Prospective descriptive study. University teaching hospital. Nine Walker hounds. A total of 27 jugular catheterizations were performed postcardiac arrest using ultrasound guidance. Catheterizations were recorded based on the order in which they were performed and presence/absence of a hematoma around the vein. Time (minutes) until successful vascular access and perceived difficulty in achieving vascular access (scale of 1 = easy to 10 = difficult) were recorded for each catheterization. Mean time to vascular access was 1.9 minutes (95% confidence interval, 1.1-3.4 min) for catheterizations without hematoma, versus 4.3 minutes (1.8-10.1 min) for catheterizations with hematoma (P = 0.1). Median perceived difficulty was 2 of 10 (range 1-7) for catheterizations without hematoma, versus 2 of 10 (range 1-8) for catheterizations with hematoma (P = 0.3). A learning curve was evaluated by comparing mean time to vascular access and perceived difficulty in initial versus subsequent catheterizations. Mean time to vascular access was 2.5 minutes (1.0-6.4 min) in the initial 13 catheterizations versus 3.3 minutes (1.5-7.5 min) in the subsequent 14 catheterizations (P = 0.6). Median perceived difficulty in the first 13 catheterizations (3, range 1-8) was significantly greater (P = 0.049) than median perceived difficulty in the subsequent 14 catheterizations (2, range 1-6). Ultrasound-guided jugular catheterization is associated with a learning curve but is successful in obtaining rapid vascular access in dogs. Further prospective studies are warranted to confirm the utility of this technique in a clinical setting. © Veterinary Emergency and Critical Care Society 2013.

  11. Focused ultrasound subthalamotomy in patients with asymmetric Parkinson's disease: a pilot study.

    Science.gov (United States)

    Martínez-Fernández, Raul; Rodríguez-Rojas, Rafael; Del Álamo, Marta; Hernández-Fernández, Frida; Pineda-Pardo, Jose A; Dileone, Michele; Alonso-Frech, Fernando; Foffani, Guglielmo; Obeso, Ignacio; Gasca-Salas, Carmen; de Luis-Pastor, Esther; Vela, Lydia; Obeso, José A

    2018-01-01

    Ablative neurosurgery has been used to treat Parkinson's disease for many decades. MRI-guided focused ultrasound allows focal lesions to be made in deep brain structures without skull incision. We investigated the safety and preliminary efficacy of unilateral subthalamotomy by focused ultrasound in Parkinson's disease. This prospective, open-label pilot study was done at CINAC (Centro Integral de Neurociencias), University Hospital HM Puerta del Sur in Madrid, Spain. Eligible participants had Parkinson's disease with markedly asymmetric parkinsonism. Patients with severe dyskinesia, history of stereotactic surgery or brain haemorrhage, a diagnosis of an unstable cardiac or psychiatric disease, or a skull density ratio of 0·3 or less were excluded. Enrolled patients underwent focused ultrasound unilateral subthalamotomy. The subthalamic nucleus was targeted by means of brain images acquired with a 3-Tesla MRI apparatus. Several sonications above the definitive ablation temperature of 55°C were delivered and adjusted according to clinical response. The primary outcomes were safety and a change in the motor status of the treated hemibody as assessed with part III of the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS III) in both off-medication and on-medication states at 6 months. Adverse events were monitored up to 48 h after treatment and at scheduled clinic visits at 1, 3, and 6 months after treatment. The study is registered with ClinicalTrials.gov, number NCT02912871. Between April 26 and June 14, 2016, ten patients with markedly asymmetric parkinsonism that was poorly controlled pharmacologically were enrolled for focused ultrasound unilateral subthalamotomy. By 6 months follow-up, 38 incidents of adverse events had been recorded, none of which were serious or severe. Seven adverse events were present at 6 months. Three of these adverse events were directly related to subthalamotomy: off-medication dyskinesia in the treated arm

  12. Laparoscopic Ultrasound-Guided Radiofrequency Ablation of Uterine Fibroids

    International Nuclear Information System (INIS)

    Milic, Andrea; Asch, Murray R.; Hawrylyshyn, Peter A.; Allen, Lisa M.; Colgan, Terence J.; Kachura, John R.; Hayeems, Eran B.

    2006-01-01

    Four patients with symptomatic uterine fibroids measuring less than 6 cm underwent laparoscopic ultrasound-guided radiofrequency ablation (RFA) using multiprobe-array electrodes. Follow-up of the treated fibroids was performed with gadolinium-enhanced magnetic resonance imaging (MRI) and patients' symptoms were assessed by telephone interviews. The procedure was initially technically successful in 3 of the 4 patients and MRI studies at 1 month demonstrated complete fibroid ablation. Symptom improvement, including a decrease in menstrual bleeding and pain, was achieved in 2 patients at 3 months. At 7 months, 1 of these 2 patients experienced symptom worsening which correlated with recurrent fibroid on MRI. The third, initially technically successfully treated patient did not experience any symptom relief after the procedure and was ultimately diagnosed with adenomyosis. Our preliminary results suggest that RFA is a technically feasible treatment for symptomatic uterine fibroids in appropriately selected patients

  13. Ultrasound guided transrectal catheter drainage of pelvic collections.

    Science.gov (United States)

    Thakral, Anuj; Sundareyan, Ramaniwas; Kumar, Sheo; Arora, Divya

    2015-01-01

    The transrectal approach to draining deep-seated pelvic collections may be used to drain The transrectal approach to draining deep-seated pelvic collections may be used to drain intra-abdominal collections not reached by the transabdominal approach. We discuss 6 patients with such pelvic collections treated with transrectal drainage using catheter placement via Seldinger technique. Transrectal drainage helped achieve clinical and radiological resolution of pelvic collections in 6 and 5 of 6 cases, respectively. It simultaneously helped avoid injury to intervening bowel loops and neurovascular structures using real-time visualization of armamentarium used for drainage. Radiation exposure from fluoroscopic/CT guidance was avoided. Morbidity and costs incurred in surgical exploration were reduced using this much less invasive ultrasound guided transrectal catheter drainage of deep-seated pelvic collections.

  14. Ultrasound-guided block of the axillary nerve

    DEFF Research Database (Denmark)

    Rothe, C; Lund, J; Jenstrup, M T

    2012-01-01

    The specific blocking of the axillary nerve has never been investigated clinically. We present four cases illustrating potential applications of the axillary nerve block in the perioperative setting and discuss possible directions for future research in this area. The axillary nerve blocks were all...... performed using a newly developed in-plane ultrasound-guided technique. In one patient undergoing arthroscopic shoulder surgery, we used the axillary nerve block as the only analgesic combined with propofol sedation and spontaneous breathing. Chronic shoulder pain was eliminated after the axillary nerve...... block in two patients. The pain score after arthroscopic shoulder surgery in these two patients remained low until termination of the nerve block. In a fourth patient, severe post-operative pain after osteosynthesis of a displaced proximal humerus fracture was almost eliminated after performing...

  15. Radiofrequency ablation guided by contrast-enhanced ultrasound for hepatic malignancies: Preliminary results

    International Nuclear Information System (INIS)

    Dong, Y.; Wang, W.-P.; Gan, Y.-H.; Huang, B.-J.; Ding, H.

    2014-01-01

    Aim: To evaluate whether contrast-enhanced ultrasound (CEUS)-guided radiofrequency ablation (RFA) can be performed effectively in small hepatic malignancies that are invisible or poorly visualized at traditional grey-scale ultrasonography (US). Materials and methods: The institutional ethics committee approved the study, and all patients provided written informed consent before their enrolment. The study focused on 55 patients (43 men, 12 women, age 57.4 ± 10.9 years) with 60 hepatic lesions from May 2010 to March 2011. All lesions were treated with multipolar radiofrequency ablation (RFA). During the RFA procedure, with the injection of ultrasound contrast agent (sulphur hexafluoride; SonoVue, Bracco Imaging Spa, Milan, Italy), RFA was conducted under CEUS guidance when the optimal depiction of a lesion was obtained. Artificial pleural effusions were used in those cases obstructed by the lungs. Twenty-four hours after RFA, contrast-enhanced MRI was used as the reference standard to evaluate the primary effectiveness rate and complete tumour necrosis. The follow-up time was 12–24 months (median 15 months). Results: Among 60 hepatic malignancies, CEUS detected 57 lesions (95%), which was higher than that at US (26.6%). Artificial pleural effusions were performed in three cases, resulting in the detection of three additional lesions. The insertion of RFA electrodes was monitored by CEUS in all lesions. Immediately after RFA, complete tumour necrosis were achieved in all 60 lesions as apparent at MRI, for a primary effectiveness rate of 100%. Conclusion: CEUS-guided RFA is a promising technique for targeting and improving the efficiency of treatment of hepatic malignancies. - Highlights: • CEUS guided RFA improved the detectability of hepatic malignancies indistinctive on gray-scale ultrasound. • Pre-operation CEUS helped localization of indistinctive hepatic malignancies. • CEUS guided RFA of hepatic malignancies achieved a more complete ablation

  16. Design and tests of an adaptive focusing neutron guide

    International Nuclear Information System (INIS)

    Valicu, Roxana Georgiana

    2012-01-01

    This work contains the Monte Carlo Simulations, as well as the first tests with an adaptive focusing neutron guide for creating a focus that does not depend on the wavelength of the incoming neutrons. All known neutron guides consist of a rectangular shape, built out of four glass plates. The inner side of the guide is coated with a complex structure of metal layers. This reflects and guides the neutrons (in analogy with the reflection of the light). For beam focusing neutron guides with fixed curvature can be built. For most experiments it is important that the beam is focused on to a small surface of the sample. In the case of focusing guides with fixed curvature it has been observed that the focusing (dimension and position of the beam focus) is wavelength dependent. This is why for measurements that are performed with different wavelengths it is very important to change the curvature of the neutron guide in order to obtain optimal results. In this work we have designed, constructed and tested a guide where we can change the curvature during the experiment. In this way we can obtain a variable curvature in horizontal as well as in vertical direction. For a curvature in the horizontal or vertical direction it is not necessary to move all four walls, only two of the opposed plates. The element that changes the curvature of the guide consists of an acting element (piezomotor) as well as a rod that can be operated by the piezomotor and that acts through a lever onto the plate. The action of a force and a consecutive torsion momentum at the free end of the plate changes the curvature of the whole plate in an almost parabolic way. Making use of the Monte Carlo simulations we were able to determine the optimal curvature for each wavelength of a neutron guide for the spectrometer TOFTOF installed at the Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II). First tests have shown that with an adaptive focusing guide one can gain up to a factor three in intensity at

  17. Design and tests of an adaptive focusing neutron guide

    Energy Technology Data Exchange (ETDEWEB)

    Valicu, Roxana Georgiana

    2012-08-23

    This work contains the Monte Carlo Simulations, as well as the first tests with an adaptive focusing neutron guide for creating a focus that does not depend on the wavelength of the incoming neutrons. All known neutron guides consist of a rectangular shape, built out of four glass plates. The inner side of the guide is coated with a complex structure of metal layers. This reflects and guides the neutrons (in analogy with the reflection of the light). For beam focusing neutron guides with fixed curvature can be built. For most experiments it is important that the beam is focused on to a small surface of the sample. In the case of focusing guides with fixed curvature it has been observed that the focusing (dimension and position of the beam focus) is wavelength dependent. This is why for measurements that are performed with different wavelengths it is very important to change the curvature of the neutron guide in order to obtain optimal results. In this work we have designed, constructed and tested a guide where we can change the curvature during the experiment. In this way we can obtain a variable curvature in horizontal as well as in vertical direction. For a curvature in the horizontal or vertical direction it is not necessary to move all four walls, only two of the opposed plates. The element that changes the curvature of the guide consists of an acting element (piezomotor) as well as a rod that can be operated by the piezomotor and that acts through a lever onto the plate. The action of a force and a consecutive torsion momentum at the free end of the plate changes the curvature of the whole plate in an almost parabolic way. Making use of the Monte Carlo simulations we were able to determine the optimal curvature for each wavelength of a neutron guide for the spectrometer TOFTOF installed at the Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II). First tests have shown that with an adaptive focusing guide one can gain up to a factor three in intensity at

  18. Motion compensation with skin contact control for high intensity focused ultrasound surgery in moving organs

    Science.gov (United States)

    Diodato, A.; Cafarelli, A.; Schiappacasse, A.; Tognarelli, S.; Ciuti, G.; Menciassi, A.

    2018-02-01

    High intensity focused ultrasound (HIFU) is an emerging therapeutic solution that enables non-invasive treatment of several pathologies, mainly in oncology. On the other hand, accurate targeting of moving abdominal organs (e.g. liver, kidney, pancreas) is still an open challenge. This paper proposes a novel method to compensate the physiological respiratory motion of organs during HIFU procedures, by exploiting a robotic platform for ultrasound-guided HIFU surgery provided with a therapeutic annular phased array transducer. The proposed method enables us to keep the same contact point between the transducer and the patient’s skin during the whole procedure, thus minimizing the modification of the acoustic window during the breathing phases. The motion of the target point is compensated through the rotation of the transducer around a virtual pivot point, while the focal depth is continuously adjusted thanks to the axial electronically steering capabilities of the HIFU transducer. The feasibility of the angular motion compensation strategy has been demonstrated in a simulated respiratory-induced organ motion environment. Based on the experimental results, the proposed method appears to be significantly accurate (i.e. the maximum compensation error is always under 1 mm), thus paving the way for the potential use of this technique for in vivo treatment of moving organs, and therefore enabling a wide use of HIFU in clinics.

  19. Inexpensive homemade models for ultrasound-guided vein cannulation training.

    Science.gov (United States)

    Di Domenico, Stefano; Santori, Gregorio; Porcile, Elisa; Licausi, Martina; Centanaro, Monica; Valente, Umberto

    2007-11-01

    To test the hypothesis that low-cost homemade models may be used to acquire the basic skills for ultrasound-guided central vein puncture. Training study. University transplantation department. Training was performed using three different homemade models (A, B, and C). Segments of a common rubber tourniquet (V1) and Silastic tube (V2) were used to simulate vessels within agar-based models. Overall cost for each model was less than 5 euro (US$7). For each test (test I, A-V1; II, A-V2; III, B-V1; IV, C-V2), the number of punctures and attempts needed to locate the needle inside the lumen were recorded. Each test was considered completed when participants punctured the vessels at the first attempt for three consecutive times. In test I, the mean number of punctures and attempts were 3.85 +/- 1.26 and 4.95 +/- 3.05; in test II, 4.60 +/- 1.14 and 6.30 +/- 2.51; in test III, 4.80 +/- 1.06 and 4.65 +/- 2.21; and in test IV, 4.45 +/- 1.23 and 6.05 +/- 2.92, respectively. For each test, no statistical difference was found by comparison of number of punctures and attempts for anesthesiologists versus nonanesthesiologists, men versus women, or previous experience versus no experience with central vein cannulation (CVC). Video game users obtained better results than did nonusers in test I (punctures, P = 0.033; attempts, P = 0.038), test II (punctures, P = 0.052; attempts, P = 0.011), and test IV (punctures, P = 0.001; attempts, P = 0.003). A posttraining questionnaire showed favorable opinions about the clarity of the instructions, aptness of the models, and adequacy of the training. In our operative unit, the use of ultrasound guidance for CVC increased from 2% to 23% in the first month after training. Low-cost homemade models are useful in acquiring basic coordination skills for ultrasound-guided CVC.

  20. Ultrasound guided versus landmark guided corticosteroid injection in patients with rotator cuff syndrome: Randomised controlled trial.

    Science.gov (United States)

    Bhayana, Himanshu; Mishra, Puneet; Tandon, Anupama; Pankaj, Amite; Pandey, Rohit; Malhotra, Raskesh

    2018-03-01

    Impingement syndrome is the most common differential in a patient presenting to an orthopaedic OPD with shoulder pain. Impingement syndrome is often managed with subacromial corticosteroid injection, which can be instilled using either landmark guided (LMG) approach or with the assistance of ultrasound (US). This study was envisaged to enquire whether ultrasound assistance improves the accuracy, efficacy or safety profile of the injection. 60 patients of rotator cuff syndrome underwent diagnostic ultrasound. They were randomly assigned to receive subacromial injection of 2 ml (40 mg/ml) methylprenisolone and 2 ml of 1% lignocaine combination either by US assistance (n = 30) or using LMG assistance (n = 30). The patients were evaluated before injection and on follow up visits at day 5, week 3, week 6 and 3rd month by a single assessor. The assessor was blinded of the treatment group to which patient belonged. Clinical assessment included demographic and clinical data, accuracy of injection, VAS (0-100) for pain, Constant score with goniometer evaluation of range of motion, patient's self assessment proforma and post injection side effects if any. Initial demographic, clinical and US findings in the groups exhibited no significant differences. The accuracy of US guided injections (100%) was more when compared from LMG injection (93.3%). Both VAS and Constant score showed significant improvement following steroid injection up to 3 months of follow up. However the differences in the two groups were not significant suggesting comparable efficacy of the two approaches. (Mean VAS score decrease: 27.23 for US and 25.16 for LMG, p guided injections have a higher accuracy of drug placement in the subacromial bursa, there is no difference in terms of clinical outcomes or safety profile of either of the method. Hence US guided injections seems to be unjustified, when compared to equally efficacious and cost effective LMG steroid injection.

  1. Characterization of a focusing parabolic guide using neutron radiography method

    International Nuclear Information System (INIS)

    Kardjilov, Nikolay; Boeni, Peter; Hilger, Andre; Strobl, Markus; Treimer, Wolfgang

    2005-01-01

    The aim of the investigation was to test the focusing properties of a new type of focusing neutron guide (trumpet) with parabolically shaped walls. The guide has a length of 431mm with an entrance area of 16x16mm 2 and an output area of 4x4mm 2 . The interior surfaces were coated with a supermirror-surface m=3 and due to their parabolic shape it was expected that an incident parallel beam can be focused in the focal point of the parabolas. To prove this statement the neutron intensity distribution at different distances behind the guide was recorded by means of a standard, high-resolution radiography detector. The experiments were performed at the V12b instrument at HMI with different levels of beam monochromatization demonstrating maximum intensity gains of about 25. The consideration for using the focusing guide for the purposes of cold neutron radiography will be presented

  2. [Efficacy and safety of ultrasound-guided or neurostimulator-guided bilateral axillary brachial plexus block].

    Science.gov (United States)

    Xu, C S; Zhao, X L; Zhou, H B; Qu, Z J; Yang, Q G; Wang, H J; Wang, G

    2017-10-17

    Objective: To explore the efficacy and safety of bilateral axillary brachial plexus block under the guidance of ultrasound or neurostimulator. Methods: From February 2012 to April 2014, 120 patients undergoing bilateral hand/forearm surgery in Beijing Jishuitan Hospital were enrolled and anaesthetized with bilateral axillary brachial plexus block. All patients were divided into two groups randomly using random number table: the ultrasound-guided group (group U, n =60) and the neurostimulator-guidedgroup (group N, n =60). The block was performed with 0.5% ropivacaine. Patients' age, sex and operation duration were recorded. Moreover, success rate, performance time, onset of sensor and motor block, performance pain, patient satisfaction degree and the incidence of related complications were also documented. Venous samples were collected at selected time points and the total and the plasma concentrations of ropivacaine were analyzed with HPLC. Results: The performance time, the onset of sensor block and the onset of motor block of group U were (8.2±1.5), (14.2± 2.2)and (24.0±3.5)min respectively, which were markedly shorter than those in group N( (14.6±3.9), (19.9±3.8), (28.8±4.2)min, respectively), and the differences were statistically significant( t =11.74, 10.09, 6.73, respectively, all P 0.05). No analgesic was superadded and no other anesthesia methods were applied. No complications were detected perioperatively. Conclusions: The bilateral axillary brachial plexus block under the guidance of ultrasound or neurostimulator are both effective and safe for bilateral hand/forearm surgery. However, the ultrasound-guided block may be more clinically beneficial because of its shorter performance time, rapid onset and higher patient satisfaction degree.

  3. Ultrasound- versus palpation-guided injection of corticosteroid for plantar fasciitis: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Zonghuan Li

    Full Text Available It is controversial whether ultrasound-guided injection of corticosteroid is superior to palpation-guided injection for plantar fasciitis. This meta-analysis was performed to compare the effectiveness of ultrasound-guided and palpation-guided injection of corticosteroid for the treatment of plantar fasciitis.Databases (MEDLINE, Cochrane library and EMBASE and reference lists were searched from their establishment to August 30, 2013 for randomized controlled trials (RCTs comparing ultrasound-guided with palpation-guided injection for plantar fasciitis. The Cochrane risk of bias (ROB tool was used to assess the methodological quality. Outcome measurements were visual analogue scale (VAS, tenderness threshold (TT, heel tenderness index (HTI, response rate, plantar fascia thickness (PFT, hypoechogenicity and heel pad thickness (HPT. The statistical analysis was performed with software RevMan 5.2 and Stata 12.0. When I2<50%, the fixed-effects model was adopted. Otherwise the randomized-effects model was adopted. The Grading of Recommendations Assessment, Development and Evaluation (GRADE system was used to assess the quality of evidence.Five RCTs with 149 patients were identified and analyzed. Compared with palpation-guided injection, ultrasound-guided injection was superior with regard to VAS, TT, response rate, PFT and hypoechogenicity. However, there was no statistical significance between the two groups for HPT and HTI.Ultrasound-guided injection of corticosteroid tends to be more effective than palpation-guided injection. However, it needs to be confirmed by further research.

  4. Ultrasound- versus Palpation-Guided Injection of Corticosteroid for Plantar Fasciitis: A Meta-Analysis

    Science.gov (United States)

    Yu, Aixi; Qi, Baiwen

    2014-01-01

    Background It is controversial whether ultrasound-guided injection of corticosteroid is superior to palpation-guided injection for plantar fasciitis. This meta-analysis was performed to compare the effectiveness of ultrasound-guided and palpation-guided injection of corticosteroid for the treatment of plantar fasciitis. Methods Databases (MEDLINE, Cochrane library and EMBASE) and reference lists were searched from their establishment to August 30, 2013 for randomized controlled trials (RCTs) comparing ultrasound-guided with palpation-guided injection for plantar fasciitis. The Cochrane risk of bias (ROB) tool was used to assess the methodological quality. Outcome measurements were visual analogue scale (VAS), tenderness threshold (TT), heel tenderness index (HTI), response rate, plantar fascia thickness (PFT), hypoechogenicity and heel pad thickness (HPT). The statistical analysis was performed with software RevMan 5.2 and Stata 12.0. When I2<50%, the fixed-effects model was adopted. Otherwise the randomized-effects model was adopted. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to assess the quality of evidence. Results Five RCTs with 149 patients were identified and analyzed. Compared with palpation-guided injection, ultrasound-guided injection was superior with regard to VAS, TT, response rate, PFT and hypoechogenicity. However, there was no statistical significance between the two groups for HPT and HTI. Conclusion Ultrasound-guided injection of corticosteroid tends to be more effective than palpation-guided injection. However, it needs to be confirmed by further research. PMID:24658102

  5. The feasibility of trans-abdominal biopsy by ultrasound guiding during uterine artery embolization for benign diseases of uterus

    International Nuclear Information System (INIS)

    Guo Wenbo; Yang Jianyong; Chen Wei; Zhuang Wenquan; Li Heping; Yao Shuzhong

    2006-01-01

    Objective: To investigate the feasibility of trans-abdominal biopsy by ultrasound guiding during uterine artery embolization (UAE) for uterine fibroids and adenomyosis. Methods: Trans-abdominal biopsies by ultrasound guiding were performed in 62 cases of uterine fibroids or adenomyosis diagnosed pre-UAE. Multi-points in focus were punctured in single lesion and multi-points in every focus of multiple lesions were punctured. The diagnosis before UAE was made according to clinical symptoms, pelvic ultrasound and pelvic magnetic resonance imaging (MRI). The pathological diagnosis by biopsy was comparative to its clinical diagnosis before biopsy. The complications were also observed. Results: Biopsies were performed successfully in 60 cases with pathological examination, including 52 uterine fibroids and 8 adenomyosis cases. The clinical diagnosis of uterine fibroids or adenomyosis was coincident with the pathology except 2 cases of fibroids diagnosed before biopsy were failed to puncture. Conclusion: Trans-abdominal biopsy by ultrasound guiding in uterine artery embolization for benign diseases of uterus is safe and feasible. (authors)

  6. Indications, results, and clinical impact of endoscopic ultrasound (EUS)-guided sampling in gastroenterology

    DEFF Research Database (Denmark)

    Dumonceau, J-M; Polkowski, M; Larghi, A

    2011-01-01

    This article is part of a combined publication that expresses the current view of the European Society of Gastrointestinal Endoscopy (ESGE) about endoscopic ultrasound (EUS)-guided sampling in gastroenterology, including EUS-guided fine needle aspiration (EUS-FNA) and EUS-guided trucut biopsy (EU...

  7. Percutaneous ultrasound-guided renal biopsy: A Libyan experience

    Science.gov (United States)

    Mishra, A.; Tarsin, R.; ElHabbash, B.; Zagan, N.; Markus, R.; Drebeka, S.; AbdElmola, K.; Shawish, T.; Shebani, A.; AbdElmola, T.; ElUsta, A.; Ehtuish, E. F.

    2010-01-01

    This study was done to assess the safety and efficacy of ultrasound-guided percutaneous renal biopsy (PRB), to ascertain the risk factors for complications and determine the optimal period of observation. The radiologist (A.M.) at the National Organ Transplant Centre, Central Hospital, Tripoli, Libya, performed 86 PRBs between February 1, 2006, and January 31, 2008, using an automated biopsy gun with 16-gauge needle. Coagulation profile was done in all the patients. All patients were kept on strict bed rest for six hours post-procedure. Eighty six renal biopsies were performed on 78 patients referred from rheumatology department and eight post-kidney transplant recipients; 23 were males with age range 15 – 56 years and 63 females with age range 16 – 66 years. A mean of 17.5 glomeruli were present in each specimen. A glomerular yield of less than five glomeruli was seen in four biopsies. Class I lupus nephritis (LN) was seen in 1 patient, class II lupus nephritis in 7 patients, class III LN in 13 patients and class IV LN in 29 patients. All the eight renal allografts were diagnosed as acute tubular necrosis or acute interstitial rejection. The risk of post-biopsy bleeding was higher in women, older patients and higher PTT. The overall complication rate was 5.8%. Three complications were observed within six hours of biopsy. No late complication was seen. PRB under real-time ultrasound-guidance is a safe and efficacious procedure to establish the histological diagnosis and should be done as out-patient procedure. Observation time of six hours post-biopsy is optimal. PMID:20835320

  8. Alleviating Pancreatic Cancer-Associated Pain Using Endoscopic Ultrasound-Guided Neurolysis

    Science.gov (United States)

    Takenaka, Mamoru; Kamata, Ken; Yoshikawa, Tomoe; Nakai, Atsushi; Omoto, Shunsuke; Miyata, Takeshi; Yamao, Kentaro; Imai, Hajime; Sakamoto, Hiroki; Kitano, Masayuki; Kudo, Masatoshi

    2018-01-01

    The most common symptom in patients with advanced pancreatic cancer is abdominal pain. This has traditionally been treated with nonsteroidal anti-inflammatory drugs and opioid analgesics. However, these treatments result in inadequate pain control or drug-related adverse effects in some patients. An alternative pain-relief modality is celiac plexus neurolysis, in which the celiac plexus is chemically ablated. This procedure was performed percutaneously or intraoperatively until 1996, when endoscopic ultrasound (EUS)-guided celiac plexus neurolysis was first described. In this transgastric anterior approach, a neurolytic agent is injected around the celiac trunk under EUS guidance. The procedure gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated pain. We focus on two relatively new techniques of EUS-guided neurolysis: EUS-guided celiac ganglia neurolysis and EUS-guided broad plexus neurolysis, which have been developed to improve efficacy. Although the techniques are safe and effective in general, some serious adverse events including ischemic and infectious complications have been reported as the procedure has gained widespread popularity. We summarize reported clinical outcomes of EUS-guided neurolysis in pancreatic cancer (from the PubMed and Embase databases) with a goal of providing information useful in developing strategies for pancreatic cancer-associated pain alleviation. PMID:29462851

  9. Application of focused ultrasounds to the measurement of the dimensions of defects in welds

    International Nuclear Information System (INIS)

    Foulquier, H.; Roule, M.; Saglio, R.; Touffait, A.M.

    1976-01-01

    Non destructive testing using ultrasounds must not only detect eventual defects but also give their nature and dimensions. C.E.A. has studied and developed focused transducers which permit the sizing of defects with high precision [fr

  10. An electro-optic spatial light modulator for thermoelastic generation of programmably focused ultrasound

    Science.gov (United States)

    1984-12-01

    The concept proposed is an electro-optic technique that would make it possible to spatially modulate a high power pulsed laser beam to thermoelastically induce focused ultrasound in a test material. Being a purely electro-optic device, the modulator, and therefore the depth at which the acoustic focus occurs, can be programmed electronically at electronic speeds. If successful, it would become possible to scan ultrasound continuously in three dimensions within the component or structure under test.

  11. Ultrasound-guided lumpectomy of nonpalpable breast cancer versus wire-guided resection: a randomized clinical trial.

    NARCIS (Netherlands)

    Rahusen, F.D.; Bremers, A.J.A.; Fabry, H.F.; Taets van Amerongen, A.H.; Boom, R.P.; Meijer, S.

    2002-01-01

    BACKGROUND: The wire-guided excision of nonpalpable breast cancer often results in tumor resections with inadequate margins. This prospective, randomized trial was undertaken to investigate whether intraoperative ultrasound (US) guidance enables a better margin clearance than the wire-guided

  12. A simple tissue model for practicing ultrasound guided vascular ...

    African Journals Online (AJOL)

    Introduction: The use of ultrasound in anaesthetic practice continues to be more established and the use of ultrasound guidance in establishing vascular access is recommended by various groups. We have developed a tissue model for the practice and skills development in ultrasound vascular access. Method: The tissue ...

  13. Design and validation of an MR-conditional robot for transcranial focused ultrasound surgery in infants

    Energy Technology Data Exchange (ETDEWEB)

    Price, Karl D., E-mail: karl.price@sickkids.ca [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, Ontario M5G 1X8 (Canada); The Department of Mechanical Engineering, The University of Toronto, Toronto, Ontario M5S 3G8 (Canada); Sin, Vivian W. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, Ontario M5G 1X8 (Canada); Mougenot, Charles [Philips Healthcare Canada, Markham, Ontario L6C 2S3 (Canada); Pichardo, Samuel [Electrical Engineering, Lakehead University, Thunder Bay, Ontario P7B 5E1 (Canada); Looi, Thomas [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, Ontario M5G 1X8 (Canada); The Institute of Biomaterials and Biomedical Engineering, The University of Toronto, Toronto, Ontario M5G 3G9 (Canada); Waspe, Adam C. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, Ontario M5G 1X8 (Canada); Department of Medical Imaging, The University of Toronto, Toronto, Ontario M5T 1W7 (Canada); Drake, James M. [Centre for Image Guided Innovation and Therapeutic Intervention, The Hospital for Sick Children, Toronto, Ontario M5G 1X8 (Canada); Department of Neurosurgery, The University of Toronto, Toronto, Ontario M5S 1A1 (Canada); The Institute of Biomaterials and Biomedical Engineering, The University of Toronto, Toronto, Ontario M5G 3G9 (Canada)

    2016-09-15

    Purpose: Current treatment of intraventricular hemorrhage (IVH) involves cerebral shunt placement or an invasive brain surgery. Magnetic resonance-guided focused ultrasound (MRgFUS) applied to the brains of pediatric patients presents an opportunity to treat IVH in a noninvasive manner, termed “incision-less surgery.” Current clinical and research focused ultrasound systems lack the capability to perform neonatal transcranial surgeries due to either range of motion or dexterity requirements. A novel robotic system is proposed to position a focused ultrasound transducer accurately above the head of a neonatal patient inside an MRI machine to deliver the therapy. Methods: A clinical Philips Sonalleve MRgFUS system was expanded to perform transcranial treatment. A five degree-of-freedom MR-conditional robot was designed and manufactured using MR compatible materials. The robot electronics and control were integrated into existing Philips electronics and software interfaces. The user commands the position of the robot with a graphical user interface, and is presented with real-time MR imaging of the patient throughout the surgery. The robot is validated through a series of experiments that characterize accuracy, signal-to-noise ratio degeneration of an MR image as a result of the robot, MR imaging artifacts generated by the robot, and the robot’s ability to operate in a representative surgical environment inside an MR machine. Results: Experimental results show the robot responds reliably within an MR environment, has achieved 0.59 ± 0.25 mm accuracy, does not produce severe MR-imaging artifacts, has a workspace providing sufficient coverage of a neonatal brain, and can manipulate a 5 kg payload. A full system demonstration shows these characteristics apply in an application environment. Conclusions: This paper presents a comprehensive look at the process of designing and validating a new robot from concept to implementation for use in an MR environment. An MR

  14. Design and validation of an MR-conditional robot for transcranial focused ultrasound surgery in infants

    International Nuclear Information System (INIS)

    Price, Karl D.; Sin, Vivian W.; Mougenot, Charles; Pichardo, Samuel; Looi, Thomas; Waspe, Adam C.; Drake, James M.

    2016-01-01

    Purpose: Current treatment of intraventricular hemorrhage (IVH) involves cerebral shunt placement or an invasive brain surgery. Magnetic resonance-guided focused ultrasound (MRgFUS) applied to the brains of pediatric patients presents an opportunity to treat IVH in a noninvasive manner, termed “incision-less surgery.” Current clinical and research focused ultrasound systems lack the capability to perform neonatal transcranial surgeries due to either range of motion or dexterity requirements. A novel robotic system is proposed to position a focused ultrasound transducer accurately above the head of a neonatal patient inside an MRI machine to deliver the therapy. Methods: A clinical Philips Sonalleve MRgFUS system was expanded to perform transcranial treatment. A five degree-of-freedom MR-conditional robot was designed and manufactured using MR compatible materials. The robot electronics and control were integrated into existing Philips electronics and software interfaces. The user commands the position of the robot with a graphical user interface, and is presented with real-time MR imaging of the patient throughout the surgery. The robot is validated through a series of experiments that characterize accuracy, signal-to-noise ratio degeneration of an MR image as a result of the robot, MR imaging artifacts generated by the robot, and the robot’s ability to operate in a representative surgical environment inside an MR machine. Results: Experimental results show the robot responds reliably within an MR environment, has achieved 0.59 ± 0.25 mm accuracy, does not produce severe MR-imaging artifacts, has a workspace providing sufficient coverage of a neonatal brain, and can manipulate a 5 kg payload. A full system demonstration shows these characteristics apply in an application environment. Conclusions: This paper presents a comprehensive look at the process of designing and validating a new robot from concept to implementation for use in an MR environment. An MR

  15. Musculoskeletal ultrasound: how to treat calcific tendinitis of the rotator cuff by ultrasound-guided single-needle lavage technique.

    Science.gov (United States)

    Lee, Kenneth S; Rosas, Humberto G

    2010-09-01

    The purpose of this video article is to illustrate the ultrasound appearance of calcium deposition in the rotator cuff and provide a detailed step-by-step protocol for performing the ultrasound-guided single-needle lavage technique for the treatment of calcific tendinitis with emphasis on patient positioning, necessary supplies, real-time lavage technique, and steroid injection into the subacromial subdeltoid bursa. Musculoskeletal ultrasound is well established as a safe, cost-effective imaging tool in diagnosing and treating common musculoskeletal disorders. Calcific tendinitis of the rotator cuff is a common disabling cause of shoulder pain. Although most cases are self-limiting, a subset of patients is refractory to conservative therapy and requires treatment intervention. Ultrasound-guided lavage is an effective and safe minimally-invasive treatment not readily offered in the United States as an alternative to surgery, perhaps because of the limited prevalence of musculoskeletal ultrasound programs and limited training. On completion of this video article, the participant should be able to develop an appropriate diagnostic and therapeutic algorithm for the treatment of calcific tendinitis of the rotator cuff using ultrasound.

  16. Comparative study between ultrasound guided TAP block and paravertebral block in upper abdominal surgeries

    Directory of Open Access Journals (Sweden)

    Ruqaya M Elsayed Goda

    2017-01-01

    Conclusion: We concluded that ultrasound guided transverses abdominis plane block and thoracic paravertebral block were safe and effective anesthetic technique for upper abdominal surgery with longer and potent postoperative analgesia in thoracic paravertebral block than transverses abdominis block.

  17. Ultrasound-Guided Intervention for Treatment of Trigeminal Neuralgia: An Updated Review of Anatomy and Techniques

    Directory of Open Access Journals (Sweden)

    Abdallah El-Sayed Allam

    2018-01-01

    Full Text Available Orofacial myofascial pain is prevalent and most often results from entrapment of branches of the trigeminal nerves. It is challenging to inject branches of the trigeminal nerve, a large portion of which are shielded by the facial bones. Bony landmarks of the cranium serve as important guides for palpation-guided injections and can be delineated using ultrasound. Ultrasound also provides real-time images of the adjacent muscles and accompanying arteries and can be used to guide the needle to the target region. Most importantly, ultrasound guidance significantly reduces the risk of collateral injury to vital neurovascular structures. In this review, we aimed to summarize the regional anatomy and ultrasound-guided injection techniques for the trigeminal nerve and its branches, including the supraorbital, infraorbital, mental, auriculotemporal, maxillary, and mandibular nerves.

  18. Proactive error analysis of ultrasound-guided axillary brachial plexus block performance.

    LENUS (Irish Health Repository)

    O'Sullivan, Owen

    2012-07-13

    Detailed description of the tasks anesthetists undertake during the performance of a complex procedure, such as ultrasound-guided peripheral nerve blockade, allows elements that are vulnerable to human error to be identified. We have applied 3 task analysis tools to one such procedure, namely, ultrasound-guided axillary brachial plexus blockade, with the intention that the results may form a basis to enhance training and performance of the procedure.

  19. Size and Ultrasound Features Affecting Results of Ultrasound-Guided Fine-Needle Aspiration of Thyroid Nodules.

    Science.gov (United States)

    Dong, YiJie; Mao, MinJing; Zhan, WeiWei; Zhou, JianQiao; Zhou, Wei; Yao, JieJie; Hu, YunYun; Wang, Yan; Ye, TingJun

    2017-11-09

    Our goal was to assess the diagnostic efficacy of ultrasound (US)-guided fine-needle aspiration (FNA) of thyroid nodules according to size and US features. A retrospective correlation was made with 1745 whole thyroidectomy and hemithyroidectomy specimens with preoperative US-guided FNA results. All cases were divided into 5 groups according to nodule size (≤5, 5.1-10, 10.1-15, 15.1-20, and >20 mm). For target nodules, static images and cine clips of conventional US and color Doppler were obtained. Ultrasound images were reviewed and evaluated by two radiologists with at least 5 years US working experience without knowing the results of pathology, and then agreement was achieved. The Bethesda category I rate was higher in nodules larger than 15 mm (P 20 mm) with several US features tended to yield false-negative FNA results. © 2017 by the American Institute of Ultrasound in Medicine.

  20. Sonochemiluminescence observation of lipid- and polymer-shelled ultrasound contrast agents in 1.2 MHz focused ultrasound field.

    Science.gov (United States)

    Qiao, Yangzi; Cao, Hua; Zhang, Shusheng; Yin, Hui; Wan, Mingxi

    2013-01-01

    Ultrasound contrast agents (UCAs) are frequently added into the focused ultrasound field as cavitation nuclei to enhance the therapeutic efficiency. Since their presence will distort the pressure field and make the process unpredictable, comprehension of their behaviors especially the active zone spatial distribution is an important part of better monitoring and using of UCAs. As shell materials can strongly alter the acoustic behavior of UCAs, two different shells coated UCAs, lipid-shelled and polymer-shelled UCAs, in a 1.2 MHz focused ultrasound field were studied by the Sonochemiluminescence (SCL) method and compared. The SCL spatial distribution of lipid-shelled group differed from that of polymer-shelled group. The shell material and the character of focused ultrasound field work together to the SCL distribution, causing the lipid-shelled group to have a maximum SCL intensity in pre-focal region at lower input power than that of polymer-shelled group, and a brighter SCL intensity in post-focal region at high input power. The SCL inactive area of these two groups both increased with the input power. The general behavior of the UCAs can be studied by both the average SCL intensity and the backscatter signals. As polymer-shelled UCAs are more resistant to acoustic pressure, they had a higher destruction power and showed less reactivation than lipid-shelled ones. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Controlled Hyperthermia with MRI-guided Focused Ultrasound

    DEFF Research Database (Denmark)

    Hokland, Steffen; Salomir, Rares; Pedersen, Michael

    Introduction: Hyperthermia is an appealing oncological treatment since the significant regions of hypoxia contained in most solid tumours are known to be sensitive to the cytotoxic effect of heat. However, due to the seemingly insurmountable technical difficulties associated with delivering thermal......-sensitive promoters and localized drug delivery using thermo-sensitive micro-carriers. Subjects Here we will present some of the recent advances in MRI-FUS, and their technical background. This will include: 1) Real-time MRI-thermometry. 2) FUS-technology. 3) Temporal and Spatial temperature control using MRI...... and penetration depth are governed by the wavelength. Hence for US it is possible to body non-invasively position sub-millimeter focal points in deep seated regions of the. Temperature Control: Most solid tumours cover volumes larger than that of the focal region. This problem may be reduced somewhat...

  2. MR-guided Focused Ultrasound for Uterine Fibroids

    Science.gov (United States)

    ... be present in your body due to prior accidents. Foreign bodies near and especially lodged in the ... a small area of the fibroid, and the process is repeated until the entire ... without causing any chemical changes in the tissues. As the hydrogen atoms ...

  3. Ultrasound-guided versus computed tomography-scan guided biopsy of pleural-based lung lesions.

    Science.gov (United States)

    Khosla, Rahul; McLean, Anna W; Smith, Jessica A

    2016-01-01

    Computed tomography (CT) guided biopsies have long been the standard technique to obtain tissue from the thoracic cavity and is traditionally performed by interventional radiologists. Ultrasound (US) guided biopsy of pleural-based lesions, performed by pulmonologists is gaining popularity and has the advantage of multi-planar imaging, real-time technique, and the absence of radiation exposure to patients. In this study, we aim to determine the diagnostic accuracy, the time to diagnosis after the initial consult placement, and the complications rates between the two different modalities. A retrospective study of electronic medical records was done of patients who underwent CT-guided biopsies and US-guided biopsies for pleural-based lesions between 2005 and 2014 and the data collected were analyzed for comparing the two groups. A total of 158 patients underwent 162 procedures during the study period. 86 patients underwent 89 procedures in the US group, and 72 patients underwent 73 procedures in the CT group. The overall yield in the US group was 82/89 (92.1%) versus 67/73 (91.8%) in the CT group (P = 1.0). Average days to the procedure was 7.2 versus 17.5 (P = 0.00001) in the US and CT group, respectively. Complication rate was higher in CT group 17/73 (23.3%) versus 1/89 (1.1%) in the US group (P guided biopsy is similar to that of CT-guided biopsy, with a lower complication rate and a significantly reduced time to the procedure.

  4. Systematic study on the performance of elliptic focusing neutron guides

    International Nuclear Information System (INIS)

    Martin Rodriguez, D.; DiJulio, D.D.; Bentley, P.M.

    2016-01-01

    In neutron scattering experiments there is an increasing trend towards the study of smaller volume samples, which make the use of focusing optics more important. Focusing guide geometries based on conic-sections, such as those with parabolic and elliptic shapes, have been extensively used in both recently built neutron instruments and upgrades of existing hardware. A large fraction of proposed instruments at the European Spallation Source feature the requirement of good performance when measuring on small samples. The optimised design of a focusing system comes after time consuming Monte-Carlo (MC) simulations. Therefore, in order to help reduce the time needed to design such focusing systems, it is necessary to study systematically the performance of focusing guides. In the present work, we perform a theoretical analysis of the focusing properties of neutron beams, and validate them using a combination of Monte-Carlo simulations and Particle Swarm Optimisations (PSOs), where there is a close correspondence between the maximum divergence of the beam and the shape of the guide. The analytical results show that two limits can be considered, which bound a range of conic section shapes that provide optimum performance. Finally, we analyse a more realistic guide example and we give an assessment of the importance of the contribution from multiple reflections in different systems.

  5. Modelling the temperature evolution of bone under high intensity focused ultrasound

    Science.gov (United States)

    ten Eikelder, H. M. M.; Bošnački, D.; Elevelt, A.; Donato, K.; Di Tullio, A.; Breuer, B. J. T.; van Wijk, J. H.; van Dijk, E. V. M.; Modena, D.; Yeo, S. Y.; Grüll, H.

    2016-02-01

    Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has been clinically shown to be effective for palliative pain management in patients suffering from skeletal metastasis. The underlying mechanism is supposed to be periosteal denervation caused by ablative temperatures reached through ultrasound heating of the cortex. The challenge is exact temperature control during sonication as MR-based thermometry approaches for bone tissue are currently not available. Thus, in contrast to the MR-HIFU ablation of soft tissue, a thermometry feedback to the HIFU is lacking, and the treatment of bone metastasis is entirely based on temperature information acquired in the soft tissue adjacent to the bone surface. However, heating of the adjacent tissue depends on the exact sonication protocol and requires extensive modelling to estimate the actual temperature of the cortex. Here we develop a computational model to calculate the spatial temperature evolution in bone and the adjacent tissue during sonication. First, a ray-tracing technique is used to compute the heat production in each spatial point serving as a source term for the second part, where the actual temperature is calculated as a function of space and time by solving the Pennes bio-heat equation. Importantly, our model includes shear waves that arise at the bone interface as well as all geometrical considerations of transducer and bone geometry. The model was compared with a theoretical approach based on the far field approximation and an MR-HIFU experiment using a bone phantom. Furthermore, we investigated the contribution of shear waves to the heat production and resulting temperatures in bone. The temperature evolution predicted by our model was in accordance with the far field approximation and agreed well with the experimental data obtained in phantoms. Our model allows the simulation of the HIFU treatments of bone metastasis in patients and can be extended to a planning tool prior to MR

  6. Modelling the temperature evolution of bone under high intensity focused ultrasound

    International Nuclear Information System (INIS)

    Ten Eikelder, H M M; Bošnački, D; Breuer, B J T; Van Wijk, J H; Van Dijk, E V M; Modena, D; Yeo, S Y; Grüll, H; Elevelt, A; Donato, K; Di Tullio, A

    2016-01-01

    Magnetic resonance-guided high intensity focused ultrasound (MR-HIFU) has been clinically shown to be effective for palliative pain management in patients suffering from skeletal metastasis. The underlying mechanism is supposed to be periosteal denervation caused by ablative temperatures reached through ultrasound heating of the cortex. The challenge is exact temperature control during sonication as MR-based thermometry approaches for bone tissue are currently not available. Thus, in contrast to the MR-HIFU ablation of soft tissue, a thermometry feedback to the HIFU is lacking, and the treatment of bone metastasis is entirely based on temperature information acquired in the soft tissue adjacent to the bone surface. However, heating of the adjacent tissue depends on the exact sonication protocol and requires extensive modelling to estimate the actual temperature of the cortex. Here we develop a computational model to calculate the spatial temperature evolution in bone and the adjacent tissue during sonication. First, a ray-tracing technique is used to compute the heat production in each spatial point serving as a source term for the second part, where the actual temperature is calculated as a function of space and time by solving the Pennes bio-heat equation. Importantly, our model includes shear waves that arise at the bone interface as well as all geometrical considerations of transducer and bone geometry. The model was compared with a theoretical approach based on the far field approximation and an MR-HIFU experiment using a bone phantom. Furthermore, we investigated the contribution of shear waves to the heat production and resulting temperatures in bone. The temperature evolution predicted by our model was in accordance with the far field approximation and agreed well with the experimental data obtained in phantoms. Our model allows the simulation of the HIFU treatments of bone metastasis in patients and can be extended to a planning tool prior to MR

  7. Evaluation of frequency-dependent ultrasound attenuation in transparent medium using focused shadowgraph technique

    Science.gov (United States)

    Iijima, Yukina; Kudo, Nobuki

    2017-07-01

    Acoustic fields of a short-pulsed ultrasound propagating through a transparent medium with ultrasound attenuation were visualized by the focused shadowgraph technique. A brightness waveform and its spatial integrations were derived from a visualized field image and compared with a pressure waveform measured by a membrane hydrophone. The experimental results showed that first-order integration of the brightness wave has good agreement with the pressure waveforms. Frequency-dependent attenuation of the pulse propagating through castor oil was derived from brightness and pressure waveforms, and attenuation coefficients determined from focused shadowgraphy and hydrophone techniques showed good agreement. The results suggest the usefulness of the shadowgraph technique not only for the visualization of ultrasound fields but also for noncontact estimation of rough pressure waveforms and correct ultrasound attenuation.

  8. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    International Nuclear Information System (INIS)

    2015-01-01

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  9. MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

  10. Development and Implementation of an Ultrasound-Guided Peripheral Intravenous Catheter Program for Emergency Nurses.

    Science.gov (United States)

    Edwards, Courtney; Jones, Jodi

    2018-01-01

    Emergency medical care often necessitates placement of peripheral intravenous (PIV) catheters. When traditional methods for obtaining PIV access are not successful, ultrasound guidance is a rescue technique for peripheral vascular placement that improves the quality of patient care. The aim of this training program was to develop a process where emergency nurses would be competent to perform ultrasound guided PIV to improve the quality of patient care delivered while reducing throughput time. Administrative program development required creating a nursing practice statement, procedure guideline, operational plan, and competency validation. A training program comprising both didactic and hands-on training was developed and provided by emergency medicine physicians with formal ultrasound fellowship training. In determining whether the training program was adequate in preparing the student to place an ultrasound-guided PIV, 92.9% of students "agreed" or "strongly agreed." In having confidence in their ability to obtain an ultrasound guided PIV catheter placement, 35.7% of respondents "agreed" and 64.3% "strongly agreed." In finding it difficult to be successful in achieving ultrasound guided PIV catheter placement, 71.4% of students "strongly disagreed" and 14.3% "disagreed." All students (100%) felt it was a feasible task to train nurses to successfully place ultrasound-guided PIV catheters and 71.4% of students strongly support continuing to provide this training program and competency validation. Establishment of an effective didactic and hands-on training program resulted in emergency department nurses becoming competent in placement of ultrasound guided PIV catheters to provide optimal patient care. Copyright © 2017 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

  11. Ultrasound-guided compression repair of pseudoaneurysms of brachial and femoral arteries - 2 cases-

    International Nuclear Information System (INIS)

    Kim, Hak Soo; Choi, Yeon Hyeon; Kim, Ji Eun; Lee, Sang Hoon; Kim, Myung A; Kim, Tae Kyoung; Cho, Jae Min

    1994-01-01

    Ultrasound-guided compression repair of postcatherization pseudoaneurysm has been reported recently. We successfuly treated two cases of cardiac catherization-related pseudoaneurysms of brachial and femoral arteries with compression repair technique under color Doppler US-guidance. We regard US-guided compression repair as a saft and effective first-line treatment for catherization-related pseudoaneurysm

  12. Glenohumeral joint injection: a comparative study of ultrasound and fluoroscopically guided techniques before MR arthrography.

    NARCIS (Netherlands)

    Rutten, M.J.; Collins, J.M.; Maresch, B.J.; Smeets, J.H.R.; Janssen, C.M.; Kiemeney, L.A.L.M.; Jager, G.J.

    2009-01-01

    To assess the variability in accuracy of contrast media introduction, leakage, required time and patient discomfort in four different centres, each using a different image-guided glenohumeral injection technique. Each centre included 25 consecutive patients. The ultrasound-guided anterior (USa) and

  13. Ultrasound Guided Nerve Root Injection in Patients with Cervical Spondylytic Radicular Pain

    Directory of Open Access Journals (Sweden)

    LT Choong

    2009-05-01

    Full Text Available Selective cervical nerve root injection using a mixture of corticosteroid and lignocaine is a treatment option for managing cervical radiculopathic pain. The procedure is usually performed under image guided fluoroscopy or Computerized Tomograhy. Ultrasound-guided cervical nerve root block does not expose the patients and personnel to radiation. During injection, the fluid is mostly visualized in a real-time fashion. This retrospective study reviewed the effectiveness of ultrasound in guiding cervical peri-radicular injection for pain relief in patients with recalcitrant cervical radiculopathy. There were no complications reported in this series.

  14. Potential mechanism in sonodynamic therapy and focused ultrasound induced apoptosis in sarcoma 180 cells in vitro.

    Science.gov (United States)

    Tang, Wei; Liu, Quanhong; Wang, Xiaobing; Wang, Pan; Zhang, Jing; Cao, Bing

    2009-12-01

    Sonodynamic therapy employs a combination of ultrasound and a sonosensitizer to enhance the cytotoxic effect of ultrasound and promote apoptosis. However, the mechanism underlying the synergistic effect of ultrasound and hematoporphyrin is still unclear. In this study, we investigated mechanism of the induction of apoptosis by sonodynamic therapy in Sarcoma 180 cells. The cell suspension was treated by 1.75-MHz focused continuous ultrasound at an acoustic power (I(SATA)) of 1.4+/-0.07 W/cm(2) for 3 min in the absence or presence of 20 microg/ml hematoporphyrin. The proportion of apoptotic cells was determined by flow cytometry. We then analyzed the reactive oxygen species generation and localization by confocal microscopy. Western blotting and reverse transcriptase-polymerase chain reaction were used to analyze the expression of caspase-8, caspase-9, poly(ADP)-ribose polymerase, and nuclear factor-kappaB. The findings of our study indicate that ultrasound treatment induced the activation of nuclear factor-kappaB as an early stress response. When cells were pretreated with hematoporphyrin, the initial response to the therapy was the formation of (1)O(2) in the mitochondria. Our results primarily demonstrate that the mechanisms of induction of apoptosis by ultrasound and hematoporphyrin-sonodynamic therapies are very different. Our findings can provide a basis for explaining the synergistic effect of ultrasound and hematoporphyrin.

  15. High intensity focused ultrasound technology, its scope and applications in therapy and drug delivery.

    Science.gov (United States)

    Phenix, Christopher Peter; Togtema, Melissa; Pichardo, Samuel; Zehbe, Ingeborg; Curiel, Laura

    2014-01-01

    Ultrasonography is a safe, inexpensive and wide-spread diagnostic tool capable of producing real-time non-invasive images without significant biological effects. However, the propagation of higher energy, intensity and frequency ultrasound waves through living tissues can induce thermal, mechanical and chemical effects useful for a variety of therapeutic applications. With the recent development of clinically approved High Intensity Focused Ultrasound (HIFU) systems, therapeutic ultrasound is now a medical reality. Indeed, HIFU has been used for the thermal ablation of pathological lesions; localized, minimally invasive ultrasound-mediated drug delivery through the transient formation of pores on cell membranes; the temporary disruption of skin and the blood brain barrier; the ultrasound induced break-down of blood clots; and the targeted release of drugs using ultrasound and temperature sensitive drug carriers. This review seeks to engage the pharmaceutical research community by providing an overview on the biological effects of ultrasound as well as highlighting important therapeutic applications, current deficiencies and future directions.

  16. Success of ultrasound-guided versus landmark-guided arthrocentesis of hip, ankle, and wrist in a cadaver model.

    Science.gov (United States)

    Berona, Kristin; Abdi, Amin; Menchine, Michael; Mailhot, Tom; Kang, Tarina; Seif, Dina; Chilstrom, Mikaela

    2017-02-01

    The objectives of this study were to evaluate emergency medicine resident-performed ultrasound for diagnosis of effusions, compare the success of a landmark-guided (LM) approach with an ultrasound-guided (US) technique for hip, ankle and wrist arthrocentesis, and compare change in provider confidence with LM and US arthrocentesis. After a brief video on LM and US arthrocentesis, residents were asked to identify artificially created effusions in the hip, ankle and wrist in a cadaver model and to perform US and LM arthrocentesis of the effusions. Outcomes included success of joint aspiration, time to aspiration, and number of attempts. Residents were surveyed regarding their confidence in identifying effusions with ultrasound and performing LM and US arthrocentesis. Eighteen residents completed the study. Sensitivity of ultrasound for detecting joint effusion was 86% and specificity was 90%. Residents were successful with ultrasound in 96% of attempts and with landmark 89% of attempts (p=0.257). Median number of attempts was 1 with ultrasound and 2 with landmarks (p=0.12). Median time to success with ultrasound was 38s and 51s with landmarks (p=0.23). After the session, confidence in both US and LM arthrocentesis improved significantly, however the post intervention confidence in US arthrocentesis was higher than LM (4.3 vs. 3.8, p<0.001). EM residents were able to successfully identify joint effusions with ultrasound, however we were unable to detect significant differences in actual procedural success between the two modalities. Further studies are needed to define the role of ultrasound for arthrocentesis in the emergency department. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Focused Ultrasound for Essential Tremor: Review of the Evidence and Discussion of Current Hurdles

    Directory of Open Access Journals (Sweden)

    Mohammad Rohani

    2017-05-01

    Full Text Available Background. While there is no breakthrough progress in the medical treatment of essential tremor (ET, in the past decades several remarkable achievements happened in the surgical field, such as radiofrequency thalamotomy, thalamic deep brain stimulation and gamma knife thalamotomy. The most recent advance in this area is magnetic resonance-guided focused ultrasound (MRgFUS. Methods. Purpose of this review is to discuss the new developments and trials of MRgFUS in the treatment of ET and other tremor disorders. Results. MRgFUS is an incision-less surgery performed without anesthesia and ionizing radiation (no risk of cumulative dose and delayed side effects. Studies have shown the safety and effectiveness of unilateral MRgFUS-thalamotomy in the treatment of ET. It has been successfully used in few patients with Parkinson's disease-related tremor and fewer patients with Fragile X-associated Tremor/Ataxia Syndrome. Safety and long-term effects of the procedure are still unclear, as temporary and permanent adverse events have been reported as well as reoccurrence of tremor. Discussion. MRgFUS is a promising new surgical approach with still a number of unknowns and unsolved issues. It represents a valuable option particularly for patients who refused or could not be candidate for other procedures, deep brain stimulation in particular. 

  18. Focused ultrasound as a tool to input sensory information to humans (Review)

    Science.gov (United States)

    Gavrilov, L. R.; Tsirulnikov, E. M.

    2012-01-01

    This review is devoted to the analysis of studies and implementations related to the use of focused ultrasound for functional effects on neuroreceptor structures. Special attention was paid to the stimulation of neuroreceptor structures in order to input sensory information to humans. This branch of medical and physiological acoustics appeared in Russia in the early 1970s and was being efficiently developed up to the late 1980s. Then, due to lack of financial support, only individual researchers remained at this field and, as a result, we have no full- fledged theoretical research and practical implementations in this area yet. Many promising possibilities of using functional effects of focused ultrasound in medicine and physiology have remained unimplemented for a long time. However, new interesting ideas and approaches have appeared in recent years. Very recently, very questionable projects have been reported related to the use of ultrasound for targeted functional effects on the human brain performed in some laboratories. In this review, the stages of the development of scientific research devoted to the functional effects of focused ultrasound are described. By activating the neuroreceptor structures of the skin by means pulses of focused ultrasound, one can cause all the sensations perceived by human beings through the skin in everyday life, such as tactile sensations, thermal (heat and cold), tickling, itching, and various types of pain. Stimulation of the ear labyrinth of humans with normal hearing using amplitude-modulated ultrasound causes auditory sensations corresponding to an audio modulating signal (pure tones, music, speech, etc.). Activation of neuroreceptor structures by means of focused ultrasound is used for the diagnosis of various neurological and skin diseases, as well as hearing disorders. It has been shown that the activation is related to the mechanical action of ultrasound, for example, by the radiation force, as well as to the direct

  19. Ultrasound-guided injection of triamcinolone and bupivacaine in the management of De Quervain's disease.

    Science.gov (United States)

    Jeyapalan, Kanagaratnam; Choudhary, Surabhi

    2009-11-01

    The aim of this study was to describe the technique and usefulness of ultrasound-guided intrasynovial injection of triamcinolone and bupivacaine in treatment of de Quervain's disease. A total of 17 patients with symptomatic De Quervain's disease were included in this study. The procedure involved confirmation of diagnosis with ultrasound followed by guided injection of a mixture of 20 mg of triamcinolone (40 mg/ml) and 1 ml of 0.5% bupivacaine. Ultrasound guidance with a high resolution 15-Mhz footprint probe was used for injection into the first dorsal extensor compartment tendon sheath (E1). The response to ultrasound-guided injection was ascertained at the post procedure outpatient clinic appointment according to the follow-up clinic notes. There were 14 female and 3 male patients aged 29 to 74 years. Mean duration of symptoms was 8.9 months. One patient had an atypical septum in the first extensor compartment and the extensor pollicis brevis alone was involved. The mean post-injection follow-up was at 6.75 weeks. One patient was lost to follow-up. Fifteen out of 16 patients had significant symptomatic relief (93.75%). There were no immediate or delayed complications. Recurrence of symptoms was seen in 3 (20%) patients. Ultrasound-guided injection of triamcinolone and bupivacaine is safe and useful in controlling symptoms of De Quervain's disease. Correct needle placement with ultrasound guidance avoids intratendinous injection as well as local complications like fat atrophy and depigmentation.

  20. PLUS: open-source toolkit for ultrasound-guided intervention systems.

    Science.gov (United States)

    Lasso, Andras; Heffter, Tamas; Rankin, Adam; Pinter, Csaba; Ungi, Tamas; Fichtinger, Gabor

    2014-10-01

    A variety of advanced image analysis methods have been under the development for ultrasound-guided interventions. Unfortunately, the transition from an image analysis algorithm to clinical feasibility trials as part of an intervention system requires integration of many components, such as imaging and tracking devices, data processing algorithms, and visualization software. The objective of our paper is to provide a freely available open-source software platform-PLUS: Public software Library for Ultrasound-to facilitate rapid prototyping of ultrasound-guided intervention systems for translational clinical research. PLUS provides a variety of methods for interventional tool pose and ultrasound image acquisition from a wide range of tracking and imaging devices, spatial and temporal calibration, volume reconstruction, simulated image generation, and recording and live streaming of the acquired data. This paper introduces PLUS, explains its functionality and architecture, and presents typical uses and performance in ultrasound-guided intervention systems. PLUS fulfills the essential requirements for the development of ultrasound-guided intervention systems and it aspires to become a widely used translational research prototyping platform. PLUS is freely available as open source software under BSD license and can be downloaded from http://www.plustoolkit.org.

  1. Ultrasound-guided radiofrequency neurotomy in cervical spine: sonoanatomic study of a new technique in cadavers

    International Nuclear Information System (INIS)

    Lee, S.-H.; Kang, C.H.; Lee, S.-H.; Derby, R.; Yang, S.N.; Lee, J.E.; Kim, J.H.; Kim, S.S.; Lee, J.-H.

    2008-01-01

    Aim: To develop an ultrasound-guided technique for radiofrequency (RF) cervical medial branch neurotomy and to validate the accuracy of this new method. Materials and methods: Five non-embalmed, fresh cadavers were used; three male and two female cadavers with a median age at death of 67.2 years (range 50-84 years). This study was conducted in two parts. First, two of the cadavers were used to define the sonographic target point for RF cervical medial branch neurotomy using high-resolution ultrasound (12 to 5 MHz). The needles were guided to five consecutive cervical medial branches in the cadavers under ultrasound guidance. Subsequently, the position of the ultrasound-guided needle was verified using C-arm fluoroscopy. Ultrasound-guided RF neurotomy was performed to the C5 medial branches in all five cadavers. In the three cadavers not used in the first part of the study, ultrasound-guided RF neurotomy without C-arm fluoroscopic confirmation was performed to the C3-C7 medial branches. The accuracy of neurotomy was assessed by pathological examination of the cervical medial branches obtained through cadaver dissection. Results: In all five cadavers, the sonographic target point was identified in all C3-C7 segments with the 12 to 5 MHz linear transducer. In all 20 needle placements for the first and second cadavers, C-arm fluoroscopy validated proper needle tip positions. In all five cadavers, successful neurotomy was pathologically confirmed in 30 of 34 cervical medial branches. Conclusions: Ultrasound-guided cervical medial branch neurotomy was successfully performed in 30 of 34 cervical medial branches in five cadavers. However, before eliminating fluoroscopic validation of final needle tip positioning, the technique should be validated in symptomatic patients

  2. Percutaneous subclavian artery stent-graft placement following failed ultrasound guided subclavian venous access

    Directory of Open Access Journals (Sweden)

    Szkup Peter

    2006-05-01

    Full Text Available Abstract Background Ultrasound guidance for central and peripheral venous access has been proven to improve success rates and reduce complications of venous cannulation. Appropriately trained and experienced operators add significantly to diminished patient morbidity related to venous access procedures. We discuss a patient who required an arterial stent-graft to prevent arterial hemorrhage following inadvertent cannulation of the proximal, ventral, right subclavian artery related to unsuccessful ultrasound guided access of the subclavian vein. Case presentation During pre-operative preparation for aortic valve replacement and aorto-coronary bypass surgery an anesthetist attempted ultrasound guided venous access. The ultrasound guided attempt to access the right jugular vein failed and the ultrasound guided attempt at accessing the subclavian vein resulted in inappropriate placement of an 8.5 F sheath in the arterial system. Following angiographic imaging and specialist consultations, an arterial stent-graft was deployed in the right subclavian artery rather than perform an extensive anterior chest wall resection and dissection to extract the arterial sheath. The patient tolerated the procedure, without complication, despite occlusion of the right internal mammary artery and the right vertebral artery. There were no neurologic sequelae. There was no evidence of hemorrhage after subclavian artery sheath extraction and stent-graft implantation. Conclusion The attempted ultrasound guided puncture of the subclavian vein resulted in placement of an 8.5 F subclavian artery catheter. Entry of the catheter into the proximal subclavian artery beneath the medial clavicle, the medial first rib and the manubrium suggests that the operator, most likely, did not directly visualize the puncture needle enter the vessel with the ultrasound. The bones of the anterior chest impede the ultrasound beam and the vessels in this area would not be visible to ultrasound

  3. The effect of ultrasound-guided compression immediately after transrectal ultrasound-guided prostate biopsy on postbiopsy bleeding: a randomized controlled pilot study.

    Science.gov (United States)

    Park, Bong Hee; Kim, Jung Im; Bae, Sang Rak; Lee, Yong Seok; Kang, Sung Hak; Han, Chang Hee

    2017-08-01

    To evaluate whether ultrasound-guided compression performed immediately after transrectal ultrasound (TRUS)-guided prostate biopsy decreases bleeding complications. We prospectively evaluated a total of 148 consecutive patients who underwent TRUS-guided prostate biopsy between March 2015 and July 2016. Systematic 12-core prostate biopsy was performed in all patients. Of these, 100 patients were randomly assigned to one of two groups: the compression group (n = 50) underwent TRUS-guided compression on bleeding biopsy tracts immediately after prostate biopsy, while the non-compression group (n = 50) underwent TRUS-guided prostate biopsy alone. The incidence rate and duration of hematuria, hematospermia, and rectal bleeding were compared between the two groups. The incidence rates of hematuria and hematospermia were not significantly different between the two groups (60 vs. 64%, p = 0.68; 22 vs. 30%, p = 0.362, respectively, for compression vs. non-compression group). The rectal bleeding incidence was significantly lower in the compression group as compared to the non-compression group (20 vs. 44%, p = 0.01). However, there were no significant differences in the median duration of hematuria, hematospermia, or rectal bleeding between the two groups (2, 8, and 2 days vs. 2, 10, and 1 days, p > 0.05, respectively, for compression vs. non-compression group). TRUS-guided compression [p = 0.004, odds ratio (OR) 0.25] and patient age (p = 0.013, OR 0.93) were significantly protective against the occurrence of rectal bleeding after prostate biopsy in multivariable analysis. Although it has no impact on other complications, ultrasound-guided compression on bleeding biopsy tracts performed immediately after TRUS-guided prostate biopsy is an effective and practical method to treat or decrease rectal bleeding.

  4. Focusing of high power ultrasound beams and limiting values of shock wave parameters

    Science.gov (United States)

    Bessonova, O. V.; Khokhlova, V. A.; Bailey, M. R.; Canney, M. S.; Crum, L. A.

    2009-10-01

    In this work, the influence of nonlinear and diffraction effects on amplification factors of focused ultrasound systems is investigated. The limiting values of acoustic field parameters obtained by focusing of high power ultrasound are studied. The Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation was used for the numerical modeling. Solutions for the nonlinear acoustic field were obtained at output levels corresponding to both pre- and post-shock formation conditions in the focal area of the beam in a weakly dissipative medium. Numerical solutions were compared with experimental data as well as with known analytic predictions.

  5. Urinary morbidity following ultrasound-guided transperineal prostate seed implantation

    International Nuclear Information System (INIS)

    Gelblum, Daphna Y.; Potters, Louis; Ashley, Richard; Waldbaum, Robert; Wang Xiaohong; Leibel, Steven

    1999-01-01

    Purpose: To assess the urinary morbidity experienced by patients undergoing ultrasound-guided, permanent transperineal seed implantation for adenocarcinoma of the prostate. Methods and Materials: Between September 1992 and September 1997, 693 consecutive patients presented with a diagnosis of clinically localized adenocarcinoma of the prostate, and were treated with ultrasound-guided transperineal interstitial permanent brachytherapy (TPIPB). Ninety-three patients are excluded from this review, having received neoadjuvant antiandrogen therapy. TPIPB was performed with 125 I in 165 patients and with 103 Pd in 435 patients. Patients treated with implant alone received 160 Gy with 125 I (pre TG43) or 120 Gy with 103 Pd. One hundred two patients received preimplant, pelvic external beam radiation (XRT) to a dose of either 41.4 or 45 Gy because of high-risk features including PSA ≥ 10 and/or Gleason score ≥ 7. Combined modality patients received 120 Gy and 90 Gy, respectively for 125 I or 103 Pd. All patients underwent postimplant cystoscopy and placement of an indwelling Foley catheter for 24-48 h. Follow-up was at 5 weeks after implant, every 3 months for the first 2 years, and then every 6 months for subsequent years. Patients completed AUA urinary symptom scoring questionnaires at initial consultation and at each follow-up visit. Urinary toxicity was classified by the RTOG toxicity scale with the following adaptations; grade 1 urinary toxicity was symptomatic nocturia or frequency requiring none or minimal medical intervention such as phenazopyridine; grade 2 urinary toxicity was early obstructive symptomatology requiring alpha-blocker therapy; and grade 3 toxicity was considered that requiring indwelling catheters or posttreatment transurethral resection of the prostate for symptom relief. Log-rank analysis and Chi-square testing was performed to assess AUA score, prostate size, isotope selection, and the addition of XRT as possible prognosticators of

  6. Safe and stable noninvasive focal gene delivery to the mammalian brain following focused ultrasound.

    Science.gov (United States)

    Stavarache, Mihaela A; Petersen, Nicholas; Jurgens, Eric M; Milstein, Elizabeth R; Rosenfeld, Zachary B; Ballon, Douglas J; Kaplitt, Michael G

    2018-04-27

    OBJECTIVE Surgical infusion of gene therapy vectors has provided opportunities for biological manipulation of specific brain circuits in both animal models and human patients. Transient focal opening of the blood-brain barrier (BBB) by MR-guided focused ultrasound (MRgFUS) raises the possibility of noninvasive CNS gene therapy to target precise brain regions. However, variable efficiency and short follow-up of studies to date, along with recent suggestions of the potential for immune reactions following MRgFUS BBB disruption, all raise questions regarding the viability of this approach for clinical translation. The objective of the current study was to evaluate the efficiency, safety, and long-term stability of MRgFUS-mediated noninvasive gene therapy in the mammalian brain. METHODS Focused ultrasound under the control of MRI, in combination with microbubbles consisting of albumin-coated gas microspheres, was applied to rat striatum, followed by intravenous infusion of an adeno-associated virus serotype 1/2 (AAV1/2) vector expressing green fluorescent protein (GFP) as a marker. Following recovery, animals were followed from several hours up to 15 months. Immunostaining for GFP quantified transduction efficiency and stability of expression. Quantification of neuronal markers was used to determine histological safety over time, while inflammatory markers were examined for evidence of immune responses. RESULTS Transitory disruption of the BBB by MRgFUS resulted in efficient delivery of the AAV1/2 vector to the targeted rodent striatum, with 50%-75% of striatal neurons transduced on average. GFP transgene expression appeared to be stable over extended periods of time, from 2 weeks to 6 months, with evidence of ongoing stable expression as long as 16 months in a smaller cohort of animals. No evidence of substantial toxicity, tissue injury, or neuronal loss was observed. While transient inflammation from BBB disruption alone was noted for the first few days, consistent

  7. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... guide biopsy of breast cancer ( see the Ultrasound-Guided Breast Biopsy page . diagnose a variety of heart ... Articles and Media Angioplasty and Vascular Stenting Ultrasound-Guided Breast Biopsy Obstetric Ultrasound Ultrasound - Prostate Biopsies - Overview ...

  8. Endobronchial ultrasound-guided transbronchial needle aspiration for lung cancer staging: early experience in Brazil*,**

    Science.gov (United States)

    Figueiredo, Viviane Rossi; Cardoso, Paulo Francisco Guerreiro; Jacomelli, Márcia; Demarzo, Sérgio Eduardo; Palomino, Addy Lidvina Mejia; Rodrigues, Ascédio José; Terra, Ricardo Mingarini; Pego-Fernandes, Paulo Manoel; Carvalho, Carlos Roberto Ribeiro

    2015-01-01

    Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive, safe and accurate method for collecting samples from mediastinal and hilar lymph nodes. This study focused on the initial results obtained with EBUS-TBNA for lung cancer and lymph node staging at three teaching hospitals in Brazil. Methods: This was a retrospective analysis of patients diagnosed with lung cancer and submitted to EBUS-TBNA for mediastinal lymph node staging. The EBUS-TBNA procedures, which involved the use of an EBUS scope, an ultrasound processor, and a compatible, disposable 22 G needle, were performed while the patients were under general anesthesia. Results: Between January of 2011 and January of 2014, 149 patients underwent EBUS-TBNA for lymph node staging. The mean age was 66 ± 12 years, and 58% were male. A total of 407 lymph nodes were sampled by EBUS-TBNA. The most common types of lung neoplasm were adenocarcinoma (in 67%) and squamous cell carcinoma (in 24%). For lung cancer staging, EBUS-TBNA was found to have a sensitivity of 96%, a specificity of 100%, and a negative predictive value of 85%. Conclusions: We found EBUS-TBNA to be a safe and accurate method for lymph node staging in lung cancer patients. PMID:25750671

  9. Endobronchial ultrasound-guided transbronchial needle aspiration for lung cancer staging: early experience in Brazil,

    Directory of Open Access Journals (Sweden)

    Viviane Rossi Figueiredo

    2015-02-01

    Full Text Available Objective: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA is a minimally invasive, safe and accurate method for collecting samples from mediastinal and hilar lymph nodes. This study focused on the initial results obtained with EBUS-TBNA for lung cancer and lymph node staging at three teaching hospitals in Brazil. Methods: This was a retrospective analysis of patients diagnosed with lung cancer and submitted to EBUS-TBNA for mediastinal lymph node staging. The EBUS-TBNA procedures, which involved the use of an EBUS scope, an ultrasound processor, and a compatible, disposable 22 G needle, were performed while the patients were under general anesthesia. Results: Between January of 2011 and January of 2014, 149 patients underwent EBUS-TBNA for lymph node staging. The mean age was 66 ± 12 years, and 58% were male. A total of 407 lymph nodes were sampled by EBUS-TBNA. The most common types of lung neoplasm were adenocarcinoma (in 67% and squamous cell carcinoma (in 24%. For lung cancer staging, EBUS-TBNA was found to have a sensitivity of 96%, a specificity of 100%, and a negative predictive value of 85%. Conclusions: We found EBUS-TBNA to be a safe and accurate method for lymph node staging in lung cancer patients.

  10. Endobronchial ultrasound-guided transbronchial needle aspiration for lung cancer staging: early experience in Brazil.

    Science.gov (United States)

    Figueiredo, Viviane Rossi; Cardoso, Paulo Francisco Guerreiro; Jacomelli, Márcia; Demarzo, Sérgio Eduardo; Palomino, Addy Lidvina Mejia; Rodrigues, Ascédio José; Terra, Ricardo Mingarini; Pego-Fernandes, Paulo Manoel; Carvalho, Carlos Roberto Ribeiro

    2015-01-01

    Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a minimally invasive, safe and accurate method for collecting samples from mediastinal and hilar lymph nodes. This study focused on the initial results obtained with EBUS-TBNA for lung cancer and lymph node staging at three teaching hospitals in Brazil. This was a retrospective analysis of patients diagnosed with lung cancer and submitted to EBUS-TBNA for mediastinal lymph node staging. The EBUS-TBNA procedures, which involved the use of an EBUS scope, an ultrasound processor, and a compatible, disposable 22 G needle, were performed while the patients were under general anesthesia. Between January of 2011 and January of 2014, 149 patients underwent EBUS-TBNA for lymph node staging. The mean age was 66 ± 12 years, and 58% were male. A total of 407 lymph nodes were sampled by EBUS-TBNA. The most common types of lung neoplasm were adenocarcinoma (in 67%) and squamous cell carcinoma (in 24%). For lung cancer staging, EBUS-TBNA was found to have a sensitivity of 96%, a specificity of 100%, and a negative predictive value of 85%. We found EBUS-TBNA to be a safe and accurate method for lymph node staging in lung cancer patients.

  11. A practical guide to ultrasound in obstetrics and gynecology

    International Nuclear Information System (INIS)

    Sauerbrei, E.E.; Nguyen, K.T.; Nolan, R.L.

    1986-01-01

    This book reviews the indications for ultrasound during pregnancy and establishes guidelines for conducting obstetrical ultrasound examinations. A selection of scans follows. These scans depict normal female pelvic anatomy; the nongravid uterus; the ovaries and adnexae; early pregnancy (the embryonic period); the placenta; the membranes, amniotic fluid, and umbilical cord; the uterus and adnexae in pregnancy; and the fetus. The book contains information on making accurate fetal measurements and calculations

  12. Targeted disruption of the blood-brain barrier with focused ultrasound: association with cavitation activity

    International Nuclear Information System (INIS)

    McDannold, N; Vykhodtseva, N; Hynynen, K

    2006-01-01

    Acoustic emission was monitored during focused ultrasound exposures in conjunction with an ultrasound contrast agent (Optison (registered) ) in order to determine if cavitation activity is associated with the induction of blood-brain barrier disruption (BBBD). Thirty-four locations were sonicated (frequency: 260 kHz) at targets 10 mm deep in rabbit brain (N = 9). The sonications were applied at peak pressure amplitudes ranging from 0.11 to 0.57 MPa (burst length: 10 ms; repetition frequency of 1 Hz; duration: 20 s). Acoustic emission was recorded with a focused passive cavitation detector. This emission was recorded at each location during sonications with and without Optison (registered) . Detectable wideband acoustic emission was observed only at 0.40 and 0.57 MPa. BBBD was observed in contrast MRI after sonication at 0.29-0.57 MPa. The appearance of small regions of extravasated erythrocytes appeared to be associated with this wideband emission signal. The results thus suggest that BBBD resulting from focused ultrasound pulses in the presence of Optison (registered) can occur without indicators for inertial cavitation in vivo, wideband emission and extravasation. If inertial cavitation is not responsible for the BBBD, other ultrasound/microbubble interactions are likely the source. A significant increase in the emission signal due to Optison (registered) at the second and third harmonics of the ultrasound driving frequency was found to correlate with BBBD and might be useful as an online method to indicate when the disruption occurs

  13. A successful model to learn and implement ultrasound-guided venous catheterization in apheresis.

    Science.gov (United States)

    Gopalasingam, Nigopan; Thomsen, Anna-Marie Eller; Folkersen, Lars; Juhl-Olsen, Peter; Sloth, Erik

    2017-12-01

    Apheresis treatments can be performed with peripheral venous catheters (PVC), although central venous catheters (CVC) are inserted when PVCs fail or patient with history of difficult vascular access prior to the apheresis. Ultrasound guidance for PVC has shown promising results in other settings. To investigate if ultrasound guidance for PVC could be implemented among apheresis nurses. Second, how implementation of ultrasound guidance affected the number of CVCs used for apheresis per patient. Apheresis nurses completed a systematic training program for ultrasound-guided vascular access. All independent catheterizations were registered during the implementation stage. The number of CVCs in the pre- and postimplementation stages of the ultrasound guidance was compared. Six nurses completed the training program within a median of 48 days (range 38-83 days). In 77 patients, 485 independent ultrasound-guided PVC placements were performed during the implementation stage. All apheresis treatments (485/485) were accomplished using PVCs without requiring CVC as rescue. During the preimplementation stage, 125 of 273 (45.8%) procedures required a CVC for completion of apheresis procedures; during the postimplementation stage only 30 of 227 (13.2%) procedures required a CVC (p < 0.001). In the postimplementation stage, no CVCs were placed as rescue caused by failed PVCs but were only placed for patients where the ultrasound machine was unavailable. It indicates an effective success rate of 100% for ultrasound-guided PVC use. This study showed that ultrasound guidance could be implemented among apheresis nurses as a routine tool eliminating the need of CVC as a rescue. © 2017 Wiley Periodicals, Inc.

  14. Noninvasive Label-Free Detection of Micrometastases in the Lymphatics with Ultrasound-Guided Photoacoustic Imaging

    Science.gov (United States)

    2015-10-01

    imaging can be used to guide dissection. We have also successfully integrated a programmable ultrasound machine ( Verasonics Vantage ) and tunable pulsed...Mobile HE) with the programmable ultrasound machine ( Verasonics Vantage ). We have synchronized the signals to enable interleaved acquisition of US...transducer (L11-4v, Verasonics Inc.) and build a housing which effectively couples fiber optic light delivery. o What opportunities for training and

  15. Standards of the Polish Ultrasound Society – update. Ultrasound examination of thyroid gland and ultrasound-guided thyroid biopsy

    Directory of Open Access Journals (Sweden)

    Anna Trzebińska

    2014-03-01

    Full Text Available Ultrasonography is a primary imaging technique in patients with suspected thyroid disease. It allows to assess the location, size and echostructures of the thyroid gland as well as detect focal lesions, along with indication of their size, echogenicity, echostructure and vascularity. Based on these features, ultrasound examination allows to predict abnormal focal lesions for biopsy and monitor the biopsy needle track. This paper presents the standards of thyroid ultrasound examination regarding ultrasound apparatus technical requirements, scanning techniques, readings, measurements, and the description of the examination. It discusses the ultrasound features of increased malignancy risk in focal lesions (nodules found in the thyroid gland. It presents indications for fine needle aspiration biopsy of the thyroid gland for the visibility of single nodules (focal lesions and numerous lesions as well as discusses contraindications for thyroid biopsy. It describes the biopsy technique, possible complications and rules for post-biopsy monitoring of benign lesions. The paper is an update of the Standards of the Polish Ultrasound Society issued in 2011. It has been prepared on the basis of current literature, taking into account the information contained in the following publications: Thyroid ultrasound examination and Recommendations of the Polish Ultrasound Society for the performance of the FNAB of the thyroid.

  16. Ultrasound-guided thoracenthesis: the V-point as a site for optimal drainage positioning.

    Science.gov (United States)

    Zanforlin, A; Gavelli, G; Oboldi, D; Galletti, S

    2013-01-01

    In the latest years the use of lung ultrasound is increasing in the evaluation of pleural effusions, because it makes follow-up easier and drainage more efficient by providing guidance on the most appropriate sampling site. However, no standardized approach for ultrasound-guided thoracenthesis is actually available. To evaluate our usual ultrasonographic landmark as a possible standard site to perform thoracenthesis by assessing its value in terms of safety and efficiency (success at first attempt, drainage as complete as possible). Hospitalized patients with non organized pleural effusion underwent thoracenthesis after ultrasound evaluation. The point showing on ultrasound the maximum thickness of the effusion ("V-point") was chosen for drainage. 45 ultrasound guided thoracenthesis were performed in 12 months. In 22 cases there were no complications; 16 cases of cough, 2 cases of mild dyspnea without desaturation, 4 cases of mild pain; 2 cases of complications requiring medical intervention occurred. No case of pneumothorax related to the procedure was detected. In all cases drainage was successful on the first attempt. The collected values of maximum thickness at V-point (min 3.4 cm - max 15.3 cm) and drained fluid volume (min 70 ml - max 2000 ml) showed a significative correlation (p measure of the maximum thickness at V-point provides high efficiency to ultrasound guided thoracentesis and allows to estimate the amount of fluid in the pleural cavity. It is also an easy parameter that makes the proposed method quick to learn and apply.  

  17. [An easy, safe and affective method for the treatment of intussusception: ultrasound-guided hydrostatic reduction].

    Science.gov (United States)

    Ülger, Fatma Esra Bahadır; Ülger, Aykut; Karakaya, Ali Erdal; Tüten, Fatih; Katı, Ömer; Çolak, Mustafa

    2014-03-01

    Intussusception is one of the important causes of intestinal obstruction in children. Hydrostatic reduction under ultrasound guidance is a popular treatment method for intussusception. In the present study, we aimed to explain the demographic characteristics of and treatment approaches in patients diagnosed with intussusception by ultrasound. Forty-one patients diagnosed with intussusception by ultrasound between August 2011 and May 2013 were retrospectively analyzed. Twenty-four of these patients who had no contraindications had been treated with ultrasound-guided hydrostatic reduction. Twenty-four of the patients were male and 17 were female, a 1.4/1 male-to-female ratio. The majority of the patients were between the ages of 6-24 months and 2-5 years. The mean age was 31.12±26.32 months (range 3-125). Patients were more frequently diagnosed in April and May. Seventeen patients who had clinical contraindications enrolled directly for surgery. In 20 of the 24 patients who underwent ultrasound-guided hydrostatic reduction, reduction was achieved. Three experienced recurrence. In two of these patients, successful reduction was achieved with the second attempt. The remaining patient was enrolled for surgery. Hydrostatic reduction was performed 26 times on these 24 patients, and in 22, success was achieved (84.6%). No procedure-related complications occurred in the patients. Ultrasound-guided hydrostatic reduction, with its high success rates and lack of radiation risk, should be the first choice therapeutic approach for children diagnosed with intussusception.

  18. Contrast-enhanced ultrasound-guided radiofrequency ablation in inconspicuous hepatocellular carcinoma on B-mode ultrasound.

    Science.gov (United States)

    Kim, Eui Joo; Kim, Yun Soo; Shin, Seung Kak; Kwon, Oh Sang; Choi, Duck Joo; Kim, Ju Hyun

    2017-11-01

    B-mode ultrasound (US) has difficulty targeting small hepatocellular carcinomas (HCCs) with poor conspicuity during radiofrequency ablation (RFA). Contrast-enhanced ultrasound (CEUS) can improve visualization of small or inconspicuous HCCs. This study was conducted to evaluate the effectiveness of CEUS-guided RFA electrode insertion during the arterial phase in inconspicuous HCCs. Ninety-three treatment-naïve HCCs from 80 patients treated with RFA from August 2012 to December 2014 were retrospectively reviewed. Seventy-five HCCs from 65 patients underwent B-mode US-guided RFA, and 15 HCCs from 14 patients that were inconspicuous on B-mode US underwent CEUS-guided RFA during the arterial phase after injection of sulfur hexafluoride microbubbles (SonoVue®). Technical success was assessed by contrast-enhanced computed tomography within 1 week and 3 months after the procedure. The mean size of HCCs treated with CEUS-guided RFA was smaller than that of HCCs treated with B-mode US-guided RFA (1.17±0.36 vs. 1.63±0.55 cm, p=0.003). Technical success rates of CEUS-guided RFA within 1 week and 3 months were 100% (15/15) and 93.3% (14/15), respectively. Technical success rates of B-mode US-guided RFA were 97.3% (73/75) and 94.5% (69/73), respectively. CEUS-guided RFA is highly efficacious for ablation of very small and inconspicuous HCCs.

  19. Backscattering analysis of high frequency ultrasonic imaging for ultrasound-guided breast biopsy

    Science.gov (United States)

    Cummins, Thomas; Akiyama, Takahiro; Lee, Changyang; Martin, Sue E.; Shung, K. Kirk

    2017-03-01

    A new ultrasound-guided breast biopsy technique is proposed. The technique utilizes conventional ultrasound guidance coupled with a high frequency embedded ultrasound array located within the biopsy needle to improve the accuracy in breast cancer diagnosis.1 The array within the needle is intended to be used to detect micro- calcifications indicative of early breast cancers such as ductal carcinoma in situ (DCIS). Backscattering analysis has the potential to characterize tissues to improve localization of lesions. This paper describes initial results of the application of backscattering analysis of breast biopsy tissue specimens and shows the usefulness of high frequency ultrasound for the new biopsy related technique. Ultrasound echoes of ex-vivo breast biopsy tissue specimens were acquired by using a single-element transducer with a bandwidth from 41 MHz to 88 MHz utilizing a UBM methodology, and the backscattering coefficients were calculated. These values as well as B-mode image data were mapped in 2D and matched with each pathology image for the identification of tissue type for the comparison to the pathology images corresponding to each plane. Microcalcifications were significantly distinguished from normal tissue. Adenocarcinoma was also successfully differentiated from adipose tissue. These results indicate that backscattering analysis is able to quantitatively distinguish tissues into normal and abnormal, which should help radiologists locate abnormal areas during the proposed ultrasound-guided breast biopsy with high frequency ultrasound.

  20. Transbiliary intravascular ultrasound-guided diagnostic biopsy of an inaccessible pancreatic head mass

    Directory of Open Access Journals (Sweden)

    Jeffrey Forris Beecham Chick, MD, MPH, DABR

    2017-06-01

    Full Text Available Percutaneous image-guided biopsies of pancreatic malignancies may prove challenging and nondiagnostic due to a variety of anatomic considerations. For patients with complex post-surgical anatomy, such as a Roux-en-Y gastric bypass, diagnosis via endoscopic ultrasound with fine-needle aspiration may not be possible because of an inability to reach the proximal duodenum. This report describes the first diagnostic case of transbiliary intravascular ultrasound-guided biopsy of a pancreatic head mass in a patient with prior Roux-en-Y gastric bypass for which a diagnosis could not be achieved via percutaneous and endoscopic approaches. Transbiliary intravascular ultrasound-guided biopsy resulted in a diagnosis of pancreatic adenocarcinoma, allowing the initiation of chemotherapy.

  1. Disinfection of a probe used in ultrasound-guided prostate biopsy.

    Science.gov (United States)

    Rutala, William A; Gergen, Maria F; Weber, David J

    2007-08-01

    Transrectal ultrasound (TRUS)-guided prostate biopsies are among the most common outpatient diagnostic procedures in urology clinics and carry the risk of introducing pathogens that may lead to infection. To investigate the effectiveness of procedures for disinfecting a probe used in ultrasound-guided prostate biopsy. The effectiveness of disinfection was determined by inoculating 10(7) colony forming units (cfu) of Pseudomonas aeruginosa at the following 3 sites on the probe: the interior lumen of the biopsy needle guide, the outside surface of the biopsy needle guide, and the interior lumen of the ultrasound probe where the needle guide passes through the transducer. Each site was investigated separately. After inoculation, the probe was immersed in 2% glutaraldehyde for 20 minutes and then assessed for the level of microbial contamination. The results demonstrated that disinfection (ie, a reduction in bacterial load of greater than 7 log(10) cfu) could be achieved if the needle guide was removed from the probe. However, if the needle guide was left in the probe channel during immersion in 2% glutaraldehyde, disinfection was not achieved (ie, the reduction was approximately 1 log(10) cfu). Recommendations for probe disinfection are provided and include disassembling the device and immersing the probe and the needle guide separately in a high-level disinfectant.

  2. Numerical evaluation of the skull for human neuromodulation with transcranial focused ultrasound

    Science.gov (United States)

    Mueller, Jerel K.; Ai, Leo; Bansal, Priya; Legon, Wynn

    2017-12-01

    Objective. Transcranial focused ultrasound is an emerging field for human non-invasive neuromodulation, but its dosing in humans is difficult to know due to the skull. The objective of the present study was to establish modeling methods based on medical images to assess skull differences between individuals on the wave propagation of ultrasound. Approach. Computational models of transcranial focused ultrasound were constructed using CT and MR scans to solve for intracranial pressure. We explored the effect of including the skull base in models, different transducer placements on the head, and differences between 250 kHz or 500 kHz acoustic frequency for both female and male models. We further tested these features using linear, nonlinear, and elastic simulations. To better understand inter-subject skull thickness and composition effects we evaluated the intracranial pressure maps between twelve individuals at two different skull sites. Main results. Nonlinear acoustic simulations resulted in virtually identical intracranial pressure maps with linear acoustic simulations. Elastic simulations showed a difference in max pressures and full width half maximum volumes of 15% at most. Ultrasound at an acoustic frequency of 250 kHz resulted in the creation of more prominent intracranial standing waves compared to 500 kHz. Finally, across twelve model human skulls, a significant linear relationship to characterize intracranial pressure maps was not found. Significance. Despite its appeal, an inherent problem with the use of a noninvasive transcranial ultrasound method is the difficulty of knowing intracranial effects because of the skull. Here we develop detailed computational models derived from medical images of individuals to simulate the propagation of neuromodulatory ultrasound across the skull and solve for intracranial pressure maps. These methods allow for a much better understanding of the intracranial effects of ultrasound for an individual in order to

  3. Ultrasound Guided Needle Aspiration versus Surgical Drainage in the management of breast abscesses: a Ugandan experience

    Directory of Open Access Journals (Sweden)

    Chandika Alphonce B

    2012-01-01

    Full Text Available Abstract Background Despite breast abscess becoming less common in developed countries, it has remained one of the leading causes of morbidity in women in developing countries. A randomized controlled trial was conducted at Mulago hospital complex in Kampala Uganda to establish whether ultrasound guided needle aspiration is a feasible alternative treatment option for breast abscesses. Results A total of 65 females with breast abscess were analyzed, of these 33 patients were randomized into the ultrasound guided needle aspiration and 32 patients in the Incision and drainage arm. The mean age was 23.12, most of them were lactating (66.2%, primipararous (44.6% with peripheral abscesses (73.8% located in the upper lateral quadrant (56%.The mean breast size was 3.49 cm. The two groups were comparably in demographic characteristic and breast abscess size. Survival analysis showed no difference in breast abscess healing rate between the two groups (Log rank 0.24 df 1 and P = 0.63. Incision and drainage was found to be more costly than ultrasound guided aspiration (cost effective ratio of 2.85. Conclusion Ultrasound guided needle aspiration is therefore a feasible and cost effective treatment option for both lactating and non lactating breast abscesses with a diameter up to 5 cm by ultrasound in an immune competent patient

  4. Comparison of Ultrasound-Guided and Fluoroscopy-Assisted Antegrade Common Femoral Artery Puncture Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Slattery, Michael M.; Goh, Gerard S.; Power, Sarah; Given, Mark F.; McGrath, Frank P.; Lee, Michael J., E-mail: mlee@rcsi.ie [Beaumont Hospital, Department of Radiology (Ireland)

    2015-06-15

    PurposeTo prospectively compare the procedural time and complication rates of ultrasound-guided and fluoroscopy-assisted antegrade common femoral artery (CFA) puncture techniques.Materials and MethodsHundred consecutive patients, undergoing a vascular procedure for which an antegrade approach was deemed necessary/desirable, were randomly assigned to undergo either ultrasound-guided or fluoroscopy-assisted CFA puncture. Time taken from administration of local anaesthetic to vascular sheath insertion in the superficial femoral artery (SFA), patients’ age, body mass index (BMI), fluoroscopy radiation dose, haemostasis method and immediate complications were recorded. Mean and median values were calculated and statistically analysed with unpaired t tests.ResultsSixty-nine male and 31 female patients underwent antegrade puncture (mean age 66.7 years). The mean BMI was 25.7 for the ultrasound-guided (n = 53) and 25.3 for the fluoroscopy-assisted (n = 47) groups. The mean time taken for the ultrasound-guided puncture was 7 min 46 s and for the fluoroscopy-assisted technique was 9 min 41 s (p = 0.021). Mean fluoroscopy dose area product in the fluoroscopy group was 199 cGy cm{sup 2}. Complications included two groin haematomas in the ultrasound-guided group and two retroperitoneal haematomas and one direct SFA puncture in the fluoroscopy-assisted group.ConclusionUltrasound-guided technique is faster and safer for antegrade CFA puncture when compared to the fluoroscopic-assisted technique alone.

  5. Ultrasound guided TAP block versus ultrasound guided caudal block for pain relief in children undergoing lower abdominal surgeries

    Directory of Open Access Journals (Sweden)

    Wafaa Mohamed Alsadek

    2015-04-01

    Conclusion: TAP block and caudal block under ultrasound guidance proved to be safe with no recorded complications either intra or postoperatively. Patient and parent satisfaction was markedly observed in case of TAP block.

  6. [The effect of focused ultrasound on the physicochemical properties of Sarcoma 180 cell membrane].

    Science.gov (United States)

    Li, Tao; Hao, Qiao; Wang, Xiaobing; Liu, Quanhong

    2009-10-01

    This study was amied to detect the changes in the cell membrane of Sarcoma 180 (S180) cells induced by focused ultrasound and to probe the underlying mechanism. The viability of tumor cells was examined at various intensities and different treatment times by ultrasound at the frequency of 2.2MHz. Flow cytometry and fluorescence microscopy were used to detect the loading of fluorescein isothiocyanate dextran (FD500) which signifies the change of membrane permeability. The results showed that after the cells were treated by ultrasound, especially when irradiated for 60s, the number of fluorescent cell, which represented the transient change of membrane permeabilization with cell survival, increased significantly. Then the damage of cell membrane was evaluated by the measurement of lactate dehydrogenase (LDH) release which became more severe as the radiation time was increasing. The generation of lipid peroxidation was estimated using the Thibabituric Acid (TBA) method after irradiation. The results reveal that the instant cell damage effects induced by ultrasound may be related to the improved membrane lipid peroxidation levels post-treatment. The physicochemical properties of S180 cell membrane were changed by focused ultrasound. The findings also imply an exposure time-dependent pattern and suggest that the lipid peroxidation produced by acoustic cavitation may play important roles in these actions.

  7. Targeted Ultrasound-Guided Perineural Hydrodissection of the Sciatic Nerve for the Treatment of Piriformis Syndrome.

    Science.gov (United States)

    Burke, Christopher J; Walter, William R; Adler, Ronald S

    2018-05-01

    Piriformis syndrome is a common cause of lumbar, gluteal, and thigh pain, frequently associated with sciatic nerve symptoms. Potential etiologies include muscle injury or chronic muscle stretching associated with gait disturbances. There is a common pathological end pathway involving hypertrophy, spasm, contracture, inflammation, and scarring of the piriformis muscle, leading to impingement of the sciatic nerve. Ultrasound-guided piriformis injections are frequently used in the treatment of these pain syndromes, with most of the published literature describing injection of the muscle. We describe a safe, effective ultrasound-guided injection technique for the treatment of piriformis syndrome using targeted sciatic perineural hydrodissection followed by therapeutic corticosteroid injection.

  8. Ultrasound guided percutaneous fine needle aspiration biopsy of the liver with focal lesion

    International Nuclear Information System (INIS)

    Ko, Gang Seok; Yang, Hyun Cheol; Park, Byoung Lan; Kim, Byoung Geun; Sohn, Jang Sihn

    1985-01-01

    The ultrasound-guided fine needle aspirations were performed in order to diagnose a suspected neoplastic or infectious disease in 52 patients with focal liver disease. Of these, neoplastic lesions were suspected in 31 patients and infectious lesions in 21 patients ultrasonically and/or clinically. The overall accuracy for both suspected malignant and infectious disease was 79% (41/52). The primary indication for fine needle aspiration was to document the presence of malignancy and to avoid a diagnostic laparotomy, and to drain hepatic abscess. Consequently we were convinced that the ultrasound-guided percutaneous fine needle aspiration biopsy in the focal liver disease is the best method for a conclusive diagnosis

  9. Septic bursitis after ultrasound-guided percutaneous treatment of rotator cuff calcific tendinopathy.

    Science.gov (United States)

    Sconfienza, Luca Maria; Randelli, Filippo; Sdao, Silvana; Sardanelli, Francesco; Randelli, Pietro

    2014-08-01

    Calcific tendinopathy of the rotator cuff is a common condition. Ultrasound-guided percutaneous aspiration is one of several options to treat this condition. The main advantages of this procedure are short duration, good outcome, and low cost. Furthermore, only minor complications have been reported in the literature, namely, vagal reactions during the procedure and mild postprocedural pain. We report the first case of septic bursitis after ultrasound-guided percutaneous treatment of calcific tendinopathy. Although this is generally considered a very safe procedure, a risk of infection should be taken into account. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  10. Ultrasound-guided hydrostatic reduction of intestinal intussusception: description of three cases

    Directory of Open Access Journals (Sweden)

    Martha Hanemann Kim

    2008-09-01

    Full Text Available With the objective of reporting the technique of ultrasound-guided hydrostatic reduction of intestinal intussusception, three cases with confirmed diagnosis of the disease submitted to reduction with this technique are described. All cases had successful reductions with no complications. One patient experienced a recurrence of the invagination eight days after treatment, which was surgically corrected. The technique of hydrostatic reversal of intestinal intussusception guided by ultrasound may be used in place of the conventional barium enema, since it is a minimally invasive and safe method, with high rates of success and few complications.

  11. Simulation Based Investigation of Focusing Phased Array Ultrasound in Dissimilar Metal Welds

    Directory of Open Access Journals (Sweden)

    Hun-Hee Kim

    2016-02-01

    Full Text Available Flaws at dissimilar metal welds (DMWs, such as reactor coolant systems components, Control Rod Drive Mechanism (CRDM, Bottom Mounted Instrumentation (BMI etc., in nuclear power plants have been found. Notably, primary water stress corrosion cracking (PWSCC in the DMWs could cause significant reliability problems at nuclear power plants. Therefore, phased array ultrasound is widely used for inspecting surface break cracks and stress corrosion cracks in DMWs. However, inspection of DMWs using phased array ultrasound has a relatively low probability of detection of cracks, because the crystalline structure of welds causes distortion and splitting of the ultrasonic beams which propagates anisotropic medium. Therefore, advanced evaluation techniques of phased array ultrasound are needed for improvement in the probability of detection of flaws in DMWs. Thus, in this study, an investigation of focusing and steering phased array ultrasound in DMWs was carried out using a time reversal technique, and an adaptive focusing technique based on finite element method (FEM simulation. Also, evaluation of focusing performance of three different focusing techniques was performed by comparing amplitude of phased array ultrasonic signals scattered from the targeted flaw with three different time delays.

  12. Amide proton transfer imaging of high intensity focused ultrasound-treated tumor tissue

    NARCIS (Netherlands)

    Hectors, S.J.C.G.; Jacobs, I.; Strijkers, G.J.; Nicolay, K.

    2014-01-01

    Purpose: In this study, the suitability of amide proton transfer (APT) imaging as a biomarker for the characterization of high intensity focused ultrasound (HIFU)-treated tumor tissue was assessed. Methods: APT imaging was performed on tumor-bearing mice before (n=15), directly after (n=15) and at 3

  13. Amide Proton Transfer Imaging of High Intensity Focused Ultrasound-Treated Tumor Tissue

    NARCIS (Netherlands)

    Hectors, Stefanie J. C. G.; Jacobs, Igor; Strijkers, Gustav J.; Nicolay, Klaas

    2014-01-01

    PurposeIn this study, the suitability of amide proton transfer (APT) imaging as a biomarker for the characterization of high intensity focused ultrasound (HIFU)-treated tumor tissue was assessed. MethodsAPT imaging was performed on tumor-bearing mice before (n=15), directly after (n=15) and at 3

  14. T1 ρ mapping for the evaluation of high intensity focused ultrasound tumor treatment

    NARCIS (Netherlands)

    Hectors, Stefanie J. C. G.; Moonen, Rik P. M.; Strijkers, Gustav J.; Nicolay, Klaas

    2015-01-01

    This study was aimed to assess the effects of High Intensity Focused Ultrasound (HIFU) thermal ablation on tumor T1ρ . In vivo T1ρ measurements of murine tumors at various spin-lock amplitudes (B1 = 0-2000 Hz) were performed before (n = 13), directly after (n = 13) and 3 days (n = 7) after HIFU

  15. Ultrasound-Guided Single-Injection Infraclavicular Block Versus Ultrasound-Guided Double-Injection Axillary Block: A Noninferiority Randomized Controlled Trial.

    Science.gov (United States)

    Boivin, Ariane; Nadeau, Marie-Josée; Dion, Nicolas; Lévesque, Simon; Nicole, Pierre C; Turgeon, Alexis F

    2016-01-01

    Single-injection ultrasound-guided infraclavicular block is a simple, reliable, and effective technique. A simplified double-injection ultrasound-guided axillary block technique with a high success rate recently has been described. It has the advantage of being performed in a superficial and compressible location, with a potentially improved safety profile. However, its effectiveness in comparison with single-injection infraclavicular block has not been established. We hypothesized that the double-injection ultrasound-guided axillary block would show rates of complete sensory block at 30 minutes noninferior to the single-injection ultrasound-guided infraclavicular block. After approval by our research ethics committee and written informed consent, adults undergoing distal upper arm surgery were randomized to either group I, ultrasound-guided single-injection infraclavicular block, or group A, ultrasound-guided double-injection axillary block. In group I, 30 mL of 1.5% mepivacaine was injected posterior to the axillary artery. In group A, 25 mL of 1.5% mepivacaine was injected posteromedial to the axillary artery, after which 5 mL was injected around the musculocutaneous nerve. Primary outcome was the rate of complete sensory block at 30 minutes. Secondary outcomes were the onset of sensory and motor blocks, surgical success rates, performance times, and incidence of complications. All outcomes were assessed by a blinded investigator. The noninferiority of the double-injection ultrasound-guided axillary block was considered if the limits of the 90% confidence intervals (CIs) were within a 10% margin of the rate of complete sensory block of the infraclavicular block. At 30 minutes, the rate of complete sensory block was 79% in group A (90% CI, 71%-85%) compared with 91% in group I (90% CI, 85%-95%); the upper limit of CI of group A is thus included in the established noninferiority margin of 10%. The rate of complete sensory block was lower in group A (proportion

  16. A retrospective comparison of microwave ablation and high intensity focused ultrasound for treating symptomatic uterine fibroids

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Wen-Peng, E-mail: zwp215@163.com; Han, Zhi-Yu, E-mail: hanzhiyu301@hotmail.com; Zhang, Jing, E-mail: zjbch@sina.com; Liang, Ping, E-mail: liangping301@hotmail.com

    2015-03-15

    Highlights: •Both HIFU and PMWA are thermal ablation techniques and they all provide safe and reliable alternative treatment methods for uterine fibroids. •However, whether there are obvious difference between these two kinds of approaches in improving symptom, treatment time, ablation rate, regression rate and adverse events, until now, there are no clinical trials which have been performed to compare the therapeutic effects of HIFU and PMWA. •In this research, we retrospectively compare the results of these two treatment methods. •To our knowledge, our study is the first directly comparing long-term outcome after PMWA and HIFU in patients with uterine fibroids. -- Abstract: Objectives: To retrospectively compare the effectiveness and safety of percutaneous microwave ablation (PMWA) and ultrasound-guided high-intensity focused ultrasound (USgHIFU) for treating symptomatic uterine fibroids. Methods: Seventy-three women with symptomatic uterine fibroids who met the inclusion criteria were enrolled in our study from September 2012 to December 2013. Thirty-one patients with forty uterine fibroids underwent PMWA, and forty-two patients with fifty-one uterine fibroids underwent USgHIFU. A contrast-enhanced MRI was performed before and after treatment, and all patients were followed up for 6 months. Assessment endpoints included symptom severity scores (SSS), treatment time, ablation rate, fibroid regression rate and adverse events. Results: The mean age of the patients in our study was 35.4 ± 6.2 years (range, 21–49 years), and the median volume of uterine fibroids was 95.7 cm{sup 3} (60.3–131.5 cm{sup 3}). The ablation rate of uterine fibroids was 79.8 ± 18.2% and 77.1 ± 14.9% in the PMWA group and the USgHIFU group, respectively, and showed no significant difference between the groups. Changes in SSS after PMWA were similar in the PMWA group (47.7 pre-treatment vs. 29.9 post-treatment) and USgHIFU group (42.1 pre-treatment vs. 24.6 post-treatment). The

  17. Ultrasound-guided fine needle aspiration versus core needle biopsy: comparison of post-biopsy hematoma rates and risk factors.

    Science.gov (United States)

    Chae, In Hye; Kim, Eun-Kyung; Moon, Hee Jung; Yoon, Jung Hyun; Park, Vivian Y; Kwak, Jin Young

    2017-07-01

    To compare post-biopsy hematoma rates between ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy, and to investigate risk factors for post-biopsy hematoma. A total of 5304 thyroid nodules which underwent ultrasound guided biopsy were included in this retrospective study. We compared clinical and US features between patients with and without post-biopsy hematoma. Associations between these features and post-biopsy hematoma were analyzed. Post-biopsy hematoma rate was 0.8% (43/5121) for ultrasound guided-fine needle aspiration and 4.9% (9/183) for ultrasound guided-core needle biopsy (P core needle biopsy (9/179, 5.0%) than with ultrasound guided-fine needle aspiration (9/1138, 0.8%) (P core needle biopsy was the only significant risk factor for post-biopsy hematoma (adjusted Odds Ratio, 6.458, P core needle biopsy than in ultrasound guided-fine needle aspiration and ultrasound guided-core needle biopsy was the only independent factor of post-biopsy hematoma in thyroid nodules.

  18. The role of ultrasound-guided triamcinolone injection in the treatment of de Quervain's disease: treatment and a diagnostic tool?

    NARCIS (Netherlands)

    Hajder, E.; de Jonge, M. C.; van der Horst, C. M. A. M.; Obdeijn, M. C.

    2013-01-01

    The purpose of this study was to describe the technique and usefulness of ultrasound-guided intrasheath injection of triamcinolone in the treatment of de Quervain's disease (dQD). Our study was retrospective in design. Seventy-one wrists of 62 patients who were treated with an ultrasound-guided

  19. An estimation of the minimum effective anesthetic volume of 2% lidocaine in ultrasound-guided axillary brachial plexus block.

    LENUS (Irish Health Repository)

    O'Donnell, Brian D

    2009-07-01

    Ultrasound guidance facilitates precise needle and injectate placement, increasing axillary block success rates, reducing onset times, and permitting local anesthetic dose reduction. The minimum effective volume of local anesthetic in ultrasound-guided axillary brachial plexus block is unknown. The authors performed a study to estimate the minimum effective anesthetic volume of 2% lidocaine with 1:200,000 epinephrine (2% LidoEpi) in ultrasound-guided axillary brachial plexus block.

  20. Yield and Safety Profile of Ultrasound Guided Fine Needle Aspiration Cytology (FNAC) of Lymph Nodes

    International Nuclear Information System (INIS)

    Sattar, A.; Wahab, S.; Javed, A.; Shamim, S. H.

    2016-01-01

    Objective: To determine the re-biopsy rate, positive yield and safety profile of ultrasound guided fine needle aspiration cytology (FNAC) in cervical lymph nodes in terms of its complications and repeat procedures. Study Design: An analytical study. Place and Duration of Study: Department of Vascular and Interventional Radiology, Dow University Hospital, Dow University of Health Sciences, Karachi, from June to December 2013. Methodology: Eighty neck swellings, which were found to be lymph nodes on ultrasound, underwent ultrasound guided FNAC, from outpatients. Lymph nodes which were included in the study were those that were not easily palpable, located near major blood vessels, where patient refused of direct palpation and wanted image guided FNAC, those directly sent by physician for image guided FNAC and where blind biopsy remained inconclusive. Patients who refused on explanation or did not give consent were excluded. Complications and repeat biopsy were noted. Result: This study consisted of 80 cases, of which 51 cases (63.75 percentage) were female and 29 cases (36.25 percentage) were male. Repeat biopsy was required in 1 case (1.6 percentage). There were no procedure-related complications. A total of 44 cases (55 percentage) revealed evidence suggesting or confirming the existence of tuberculosis. Rest of the others showed other benign lesions, reactive lymphadenopathy and malignancy. Conclusion: Ultrasound guided FNAC is a safe procedure with low re-biopsy rate that aids diagnosis. The predominant cause of cervical lymphadenopathy in this study was tuberculous lymphadenitis. (author)

  1. Understanding focused ion beam guided anodic alumina nanopore development

    International Nuclear Information System (INIS)

    Chen Bo; Lu, Kathy; Tian Zhipeng

    2011-01-01

    Graphical abstract: Display Omitted Highlights: → We study the effect of FIB patterning on pore evolution during anodization. → FIB patterned concaves with 1.5 nm depth can effectively guide nanopore growth. → The edge effect of FIB guided patterns causes nanopores to bend. → Anodization window is enlarged to 50-80 V for 150 nm interpore distance hexagonal arrays. - Abstract: Focused ion beam (FIB) patterning in combination with anodization has shown great promise in creating unique pore patterns. This work is aimed to understand the effect of the FIB patterned sites in guiding anodized pore development. Highly ordered porous anodic alumina has been created with the guidance of FIB created patterns on electropolished aluminum followed by oxalic acid anodization. Shallow concaves created by the FIB with only 1.5 nm depth can effectively guide the growth of ordered nanopore patterns. With the guidance of the FIB pattern, the anodization rate is much faster and the nanopore growth direction bends at the boundary of the FIB patterned and un-patterned regions. FIB patterning also enlarges the anodization window; ordered nanopore arrays with 150 nm interpore distances can be produced under an applied potential from 50 V to 80 V. The fundamental understanding of these unique processes is discussed.

  2. Evaluating imaging-pathology concordance and discordance after ultrasound-guided breast biopsy

    Science.gov (United States)

    2018-01-01

    Ultrasound (US)-guided breast biopsy has become the main method for diagnosing breast pathology, and it has a high diagnostic accuracy, approaching that of open surgical biopsy. However, methods for confirming adequate lesion retrieval after US-guided biopsy are relatively limited and false-negative results are unavoidable. Determining imaging-pathology concordance after US-guided biopsy is essential for validating the biopsy result and providing appropriate management. In this review article, we briefly present the results of US-guided breast biopsy; describe general aspects to consider when establishing imaging-pathology concordance; and review the various categories of imaging-pathology correlations and corresponding management strategies. PMID:29169231

  3. Role of Ultrasound Guided Biopsy of Thoracic Lesions | Elameen ...

    African Journals Online (AJOL)

    Objective: This prospective study is to evaluate and enhance the role of ultrasound in biopsy guidance of thoracic lesions. Methods: 55 patients were subjected for fine needle aspiration (FNA) and/or core needle biopsy (CNB) from peripheral chest lesions in Ribat University Hospital during the period from April 2011 and ...

  4. Transperineal seed-implantation guided by biplanar transrectal ultrasound

    DEFF Research Database (Denmark)

    Holm, Hans Henrik; Torp-Pedersen, S; Myschetzky, P

    1990-01-01

    A new method for precise transperineal placement of therapeutic sources in prostatic cancer is described. The method is a modification of the technique described in 1983 by Holm and coworkers. Insertion of needles is monitored by transverse as well as longitudinal transrectal ultrasound....

  5. Ultrasound-guided peripheral nerve blocks: what are the benefits?

    DEFF Research Database (Denmark)

    Nielsen, Zbigniew Jerzy Koscielniak

    2008-01-01

    with the MESH terms 'nerve block' and 'ultrasonography'. The following limits were applied: studies with abstracts, only in humans, published in core clinical journals. Trial type: meta-analysis, randomized-controlled trial and clinical trial. RESULTS: When peripheral nerves are adequately imaged by ultrasound...

  6. Variables determining the success of ultrasound-guided hydrostatic ...

    African Journals Online (AJOL)

    Department of Pediatric Surgery, Faculty of Medicine, Tanta University Hospitals,. Tanta, Egypt ... Ultrasound was performed using warm normal saline 0.9% through a Foley's catheter that was passed into the rectum. Irritable infants received slow intrave- nous diazepam ... duplication cyst) and resection (13.6%) Table 4.

  7. Ultrasound-guided cryoablation of breast fibroadenoma: a pilot trial.

    Science.gov (United States)

    Golatta, Michael; Harcos, Aba; Pavlista, David; Danes, Jan; Klein, Rafi; Simovich, Paola; Gruber, Ines; Hahn, Markus

    2015-06-01

    The aim of the study was to evaluate cryoablation (CA) under ultrasound guidance in the office setting with liquid nitrogen system for patients with fibroadenoma (FA). For this prospective multicenter trial, an office-based cryosurgical system was used to treat histological confirmed benign FA with a maximum dimension of 3 cm. Sixty CA procedures were performed under ultrasound guidance. A freeze-thaw-freeze treatment cycle was performed according to the size of the FA. During the CA procedure continuous ultrasound monitoring was performed, verifying engulfment of the FA. Patients attended four follow-up visits at 1 week, 3, 6 months and 1 year and underwent ultrasound, physical examination and photography. Data were collected and analyzed in 60 cases. 59 of 60 FA (98 %) were fully engulfed by the ice ball. No serious adverse events occurred related to the IceSense3 system. At the 1-year follow-up, the FAs were gone in 93% of the cases. Prior to CA procedure, 76% of the FAs were palpable. Afterwards in some cases (22%), a scar/cryo lesion was palpable. 28% of the patients reported pain, described as mild or moderate, compared to 2% after 1 year. Cosmetic results at 12 months follow-up were reported as good or excellent in 100% by physician and in 97% by patients. The cryodestruction of the FA using liquid nitrogen system proved functional and safe, while showing meaningful reduction in volume, palpability, pain and cosmetic satisfying outcomes.

  8. Transperineal seed-implantation guided by biplanar transrectal ultrasound

    International Nuclear Information System (INIS)

    Holm, H.H.; Torp-Pedersen, S.; Myschetzky, P.

    1990-01-01

    A new method for precise transperineal placement of therapeutic sources in prostatic cancer is described. The method is a modification of the technique described in 1983 by Holm and coworkers. Insertion of needles is monitored by transverse as well as longitudinal transrectal ultrasound

  9. Simultaneous acoustic stimulation of human primary and secondary somatosensory cortices using transcranial focused ultrasound.

    Science.gov (United States)

    Lee, Wonhye; Chung, Yong An; Jung, Yujin; Song, In-Uk; Yoo, Seung-Schik

    2016-10-26

    Transcranial focused ultrasound (FUS) is gaining momentum as a novel non-invasive brain stimulation method, with promising potential for superior spatial resolution and depth penetration compared to transcranial magnetic stimulation or transcranial direct current stimulation. We examined the presence of tactile sensations elicited by FUS stimulation of two separate brain regions in humans-the primary (SI) and secondary (SII) somatosensory areas of the hand, as guided by individual-specific functional magnetic resonance imaging data. Under image-guidance, acoustic stimulations were delivered to the SI and SII areas either separately or simultaneously. The SII areas were divided into sub-regions that are activated by four types of external tactile sensations to the palmar side of the right hand-vibrotactile, pressure, warmth, and coolness. Across the stimulation conditions (SI only, SII only, SI and SII simultaneously), participants reported various types of tactile sensations that arose from the hand contralateral to the stimulation, such as the palm/back of the hand or as single/neighboring fingers. The type of tactile sensations did not match the sensations that are associated with specific sub-regions in the SII. The neuro-stimulatory effects of FUS were transient and reversible, and the procedure did not cause any adverse changes or discomforts in the subject's mental/physical status. The use of multiple FUS transducers allowed for simultaneous stimulation of the SI/SII in the same hemisphere and elicited various tactile sensations in the absence of any external sensory stimuli. Stimulation of the SII area alone could also induce perception of tactile sensations. The ability to stimulate multiple brain areas in a spatially restricted fashion can be used to study causal relationships between regional brain activities and their cognitive/behavioral outcomes.

  10. Ultrasound/Magnetic Resonance Image Fusion Guided Lumbosacral Plexus Block – A Clinical Study

    DEFF Research Database (Denmark)

    Strid, JM; Pedersen, Erik Morre; Søballe, Kjeld

    2014-01-01

    in a double-blinded randomized controlled trial with crossover design. MR datasets will be acquired and uploaded in an advanced US system (Epiq7, Phillips, Amsterdam, Netherlands). All volunteers will receive SSPS blocks with lidocaine added gadolinium contrast guided by US/MR image fusion and by US one week......Background and aims Ultrasound (US) guided lumbosacral plexus block (Supra Sacral Parallel Shift [SSPS]) offers an alternative to general anaesthesia and perioperative analgesia for hip surgery.1 The complex anatomy of the lumbosacral region hampers the accuracy of the block, but it may be improved...... by guidance of US and magnetic resonance (MR) image fusion and real-time 3D electronic needle tip tracking.2 We aim to estimate the effect and the distribution of lidocaine after SSPS guided by US/MR image fusion compared to SSPS guided by ultrasound. Methods Twenty-four healthy volunteers will be included...

  11. Ultrasound-guided percutaneous cholecysto-cholangiography for the exclusion of biliary atresia in infants

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Kyung Min; Ryeom, Hun Kyu; Choe, Byung Ho; Kim, Kap Cheol; Kim, Jong Yeol; Lee, Jong Min; Kim, Hye Jeong; Lee, Hee Jung [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2006-08-15

    The aim of this study is to determine the feasibility and effectiveness of performing an ultrasound-guided percutaneous cholecysto-cholangiogram (PCC) for excluding biliary atresia as the cause of neonatal jaundice. Between Oct. 2003 and Feb. 2005, six ultrasound-guided PCC procedures were performed to five jaundiced infants (4 females and 1 male; mean age: 60 days old) for whom possibility of biliary atresia could not be ruled out by the DISIDA scan as the cause of their neonatal jaundice. Gallbladder puncture was performed under ultrasound guidance with a 23-gauge needle. Contrast material injection during fluoroscopic examination was performed after dilatation of the gallbladder lumen with normal saline under ultrasound guidance. The criteria used for excluding biliary atresia were complete visualization of the extrahepatic biliary trees and/or contrast excretion into the duodenum. The complications and final diagnosis was assessed according to the clinical and laboratory findings. The procedures were successful in all the patients without any complication. Biliary atresia could be ruled out in all the patients. The final diagnosis was neonatal cytomegalovirus hepatitis in two patients, total parenteral nutrition-associated cholestasis in two patients, and combined cytomegalovirus hepatitis and total parenteral nutrition-associated cholestasis in one patient. Ultrasound-guided PCC is a feasible and effective method for the early definitive exclusion of biliary atresia as the cause of neonatal jaundice. By the technique of injecting normal saline before contrast injection, PCC can be done even in a totally collapsed or very small gallbladder.

  12. Ultrasound-guided percutaneous cholecysto-cholangiography for the exclusion of biliary atresia in infants

    International Nuclear Information System (INIS)

    Shin, Kyung Min; Ryeom, Hun Kyu; Choe, Byung Ho; Kim, Kap Cheol; Kim, Jong Yeol; Lee, Jong Min; Kim, Hye Jeong; Lee, Hee Jung

    2006-01-01

    The aim of this study is to determine the feasibility and effectiveness of performing an ultrasound-guided percutaneous cholecysto-cholangiogram (PCC) for excluding biliary atresia as the cause of neonatal jaundice. Between Oct. 2003 and Feb. 2005, six ultrasound-guided PCC procedures were performed to five jaundiced infants (4 females and 1 male; mean age: 60 days old) for whom possibility of biliary atresia could not be ruled out by the DISIDA scan as the cause of their neonatal jaundice. Gallbladder puncture was performed under ultrasound guidance with a 23-gauge needle. Contrast material injection during fluoroscopic examination was performed after dilatation of the gallbladder lumen with normal saline under ultrasound guidance. The criteria used for excluding biliary atresia were complete visualization of the extrahepatic biliary trees and/or contrast excretion into the duodenum. The complications and final diagnosis was assessed according to the clinical and laboratory findings. The procedures were successful in all the patients without any complication. Biliary atresia could be ruled out in all the patients. The final diagnosis was neonatal cytomegalovirus hepatitis in two patients, total parenteral nutrition-associated cholestasis in two patients, and combined cytomegalovirus hepatitis and total parenteral nutrition-associated cholestasis in one patient. Ultrasound-guided PCC is a feasible and effective method for the early definitive exclusion of biliary atresia as the cause of neonatal jaundice. By the technique of injecting normal saline before contrast injection, PCC can be done even in a totally collapsed or very small gallbladder

  13. Subacute posteromedial impingement of the ankle in athletes: MR imaging evaluation and ultrasound guided therapy

    International Nuclear Information System (INIS)

    Messiou, Christina; Robinson, Philip; O'Connor, Philip J.; Grainger, Andrew

    2006-01-01

    To describe the use of MR imaging and efficacy of ultrasound-guided steroid injection in the diagnosis and management of athletes with clinical posteromedial impingement of the ankle. A retrospective analysis of imaging findings on MR was undertaken in nine elite athletes with clinical posteromedial ankle impingement. MR studies from six professional athletes with posterolateral pain were also reviewed as an imaging control group. The two reviewing radiologists were blinded to the clinical details and the proportion of control and study subjects. The nine study athletes also underwent diagnostic ultrasound and ultrasound-guided injection of steroid and anaesthetic into the posteromedial capsular abnormality. Follow-up was by telephone interview. Posteromedial capsular thickening was seen only in athletes with posteromedial impingement (7/9). Posteromedial synovitis was present in all athletes with posteromedial impingement; however, posterior and posterolateral synovitis was also seen in these athletes. Mild posteromedial synovitis was present in two control athletes. Ultrasound identified abnormal posteromedial soft tissue thickening deep to tibialis posterior between the medial malleolus and talus in all nine athletes. After injection all athletes returned to their previous level of sport, with eight of the nine not experiencing any residual or recurrent symptoms. If MR imaging excludes significant coexistent abnormality, ultrasound can localise posteromedial soft tissue abnormality and guide injection therapy, allowing return to athletic activity without surgical intervention. (orig.)

  14. Computational exploration of wave propagation and heating from transcranial focused ultrasound for neuromodulation

    Science.gov (United States)

    Mueller, Jerel K.; Ai, Leo; Bansal, Priya; Legon, Wynn

    2016-10-01

    Objective. While ultrasound is largely established for use in diagnostic imaging, its application for neuromodulation is relatively new and crudely understood. The objective of the present study was to investigate the effects of tissue properties and geometry on the wave propagation and heating in the context of transcranial neuromodulation. Approach. A computational model of transcranial-focused ultrasound was constructed and validated against empirical data. The models were then incrementally extended to investigate a number of issues related to the use of ultrasound for neuromodulation, including the effect on wave propagation of variations in geometry of skull and gyral anatomy as well as the effect of multiple tissue and media layers, including scalp, skull, CSF, and gray/white matter. In addition, a sensitivity analysis was run to characterize the influence of acoustic properties of intracranial tissues. Finally, the heating associated with ultrasonic stimulation waveforms designed for neuromodulation was modeled. Main results. The wave propagation of a transcranially focused ultrasound beam is significantly influenced by the cranial domain. The half maximum acoustic beam intensity profiles are insensitive overall to small changes in material properties, though the inclusion of sulci in models results in greater peak intensity values compared to a model without sulci (1%-30% greater). Finally, heating using currently employed stimulation parameters in humans is highest in bone (0.16 °C) and is negligible in brain (4.27 × 10-3 °C) for a 0.5 s exposure. Significance. Ultrasound for noninvasive neuromodulation holds great promise and appeal for its non-invasiveness, high spatial resolution and deep focal lengths. Here we show gross brain anatomy and biological material properties to have limited effect on ultrasound wave propagation and to result in safe heating levels in the skull and brain.

  15. Intravascular ultrasound guided directional atherectomy versus directional atherectomy guided by angiography for the treatment of femoropopliteal in-stent restenosis

    Science.gov (United States)

    Krishnan, Prakash; Tarricone, Arthur; K-Raman, Purushothaman; Majeed, Farhan; Kapur, Vishal; Gujja, Karthik; Wiley, Jose; Vasquez, Miguel; Lascano, Rheoneil A.; Quiles, Katherine G.; Distin, Tashanne; Fontenelle, Ran; Atallah-Lajam, Farah; Kini, Annapoorna; Sharma, Samin

    2017-01-01

    Background: The aim of this study was to compare 1-year outcomes for patients with femoropopliteal in-stent restenosis using directional atherectomy guided by intravascular ultrasound (IVUS) versus directional atherectomy guided by angiography. Methods and results: This was a retrospective analysis for patients with femoropopliteal in-stent restenosis treated with IVUS-guided directional atherectomy versus directional atherectomy guided by angiography from a single center between March 2012 and February 2016. Clinically driven target lesion revascularization was the primary endpoint and was evaluated through medical chart review as well as phone call follow up. Conclusions: Directional atherectomy guided by IVUS reduces clinically driven target lesion revascularization for patients with femoropopliteal in-stent restenosis. PMID:29265002

  16. Laser-Induced Focused Ultrasound for Cavitation Treatment: Toward High-Precision Invisible Sonic Scalpel.

    Science.gov (United States)

    Lee, Taehwa; Luo, Wei; Li, Qiaochu; Demirci, Hakan; Guo, L Jay

    2017-10-01

    Beyond the implementation of the photoacoustic effect to photoacoustic imaging and laser ultrasonics, this study demonstrates a novel application of the photoacoustic effect for high-precision cavitation treatment of tissue using laser-induced focused ultrasound. The focused ultrasound is generated by pulsed optical excitation of an efficient photoacoustic film coated on a concave surface, and its amplitude is high enough to produce controllable microcavitation within the focal region (lateral focus <100 µm). Such microcavitation is used to cut or ablate soft tissue in a highly precise manner. This work demonstrates precise cutting of tissue-mimicking gels as well as accurate ablation of gels and animal eye tissues. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Ultrasound-guided procedures around the wrist and hand: How to do

    International Nuclear Information System (INIS)

    Orlandi, Davide; Corazza, Angelo; Silvestri, Enzo; Serafini, Giovanni; Savarino, Edoardo Vincenzo; Garlaschi, Giacomo; Mauri, Giovanni; Cimmino, Marco Amedeo; Sconfienza, Luca Maria

    2014-01-01

    Ultrasound has emerged as a low-cost, radiation-free and effective imaging technique to detect joint abnormalities and to guide percutaneous procedures. Being superficial, wrist and hand tendons and joints represent a good target to perform such procedures using ultrasound guidance. This kind of approach allows for a clear and real-time visualization of the needles during their whole path. In this setting, the knowledge of technical aspects and tips is essential to act in the most accurate way on target tissues that can be as small as a few millimetres. The aim of this review is to summarize the local treatments of inflammatory and degenerative disease described in literature (such as treatment of De Quervain's tenosynovitis, trigger finger, trapezio-metacarpal joint osteoarthritis, etc.), emphasizing precautions and tricks based on day-by-day experience that may help to improve the outcome of percutaneous ultrasound-guided procedures around the wrist and hand

  18. Ultrasound-Guided Femoral Nerve Block to Facilitate the Closed Reduction of a Dislocated Hip Prosthesis

    Directory of Open Access Journals (Sweden)

    Edward Carlin

    2017-10-01

    Full Text Available Prosthetic hip dislocation is a common but unfortunate complication in patients who have undergone total hip arthroplasty. Successful closed reduction in the emergency department leads to a reduced length of stay and rate of hospitalization. 1, 2 The use of regional anesthesia by femoral nerve block represents a novel approach for controlling pain in patients with hip pathologies. 3 Ultrasound-guided approaches have been used with great success for controlling pain in patients with hip fractures. 4, 5 Here we report the case of a 90-year-old male who presented with a dislocated hip prosthesis, which was subsequently corrected with closed reduction following delivery of regional anesthesia to the femoral nerve under ultrasound guidance. To our knowledge, this represents the first reported use of an ultrasound-guided femoral nerve block to facilitate closed reduction of a dislocated prosthetic hip, and highlights a novel approach that avoids the use of procedural sedation in an elderly patient.

  19. Ultrasound-guided procedures around the wrist and hand: How to do

    Energy Technology Data Exchange (ETDEWEB)

    Orlandi, Davide; Corazza, Angelo [Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Genova, Via L.B. Alberti 4, 16132 Genova (Italy); Silvestri, Enzo [Diagnostica per Immagini, Ospedale Evangelico Internazionale, Corso Solferino 29A, 16100 Genova (Italy); Serafini, Giovanni [Dipartimento di Diagnostica per Immagini, Ospedale Santa Corona, Via XXV Aprile 38, 17037 Pietra Ligure, Savona (Italy); Savarino, Edoardo Vincenzo [Dipartimento di Scienze Chirurgiche, Oncologiche e Gastroenterologiche, Università degli Studi di Padova, Via Giustiniani, Padova (Italy); Garlaschi, Giacomo [Dipartimento di Scienze per la Salute, Università degli Studi di Genova, Via L.B. Alberti 4, 16132 Genova (Italy); Mauri, Giovanni [Servizio di Radiologia, IRCCS Policlinico San Donato, Piazza Malan 2, San Donato Milanese, Milano (Italy); Cimmino, Marco Amedeo [Dipartimento di Medicina Interna, Università degli Studi di Genova, Via L.B. Alberti 4, 16132 Genova (Italy); Sconfienza, Luca Maria, E-mail: io@lucasconfienza.it [Servizio di Radiologia, IRCCS Policlinico San Donato, Piazza Malan 2, San Donato Milanese, Milano (Italy); Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Piazza Malan 2, San Donato Milanese, Milano (Italy)

    2014-07-15

    Ultrasound has emerged as a low-cost, radiation-free and effective imaging technique to detect joint abnormalities and to guide percutaneous procedures. Being superficial, wrist and hand tendons and joints represent a good target to perform such procedures using ultrasound guidance. This kind of approach allows for a clear and real-time visualization of the needles during their whole path. In this setting, the knowledge of technical aspects and tips is essential to act in the most accurate way on target tissues that can be as small as a few millimetres. The aim of this review is to summarize the local treatments of inflammatory and degenerative disease described in literature (such as treatment of De Quervain's tenosynovitis, trigger finger, trapezio-metacarpal joint osteoarthritis, etc.), emphasizing precautions and tricks based on day-by-day experience that may help to improve the outcome of percutaneous ultrasound-guided procedures around the wrist and hand.

  20. Minimally Invasive Ultrasound-Guided Carpal Tunnel Release: Preliminary Clinical Results.

    Science.gov (United States)

    Henning, P Troy; Yang, Lynda; Awan, Tariq; Lueders, Daniel; Pourcho, Adam M

    2018-04-02

    Ultrasound-guided carpal tunnel release was performed on 14 patients (18 wrists) using dynamic expansion of the transverse safe zone. Our patient population included able-bodied patients and those with impairments. The first 8 cases (12 wrists) underwent the procedure in an operating room, the remainder in an outpatient setting. No complications occurred, and all patients were able to immediately resume use of their hands without therapy. Improvements in the Quick Form of the Disabilities of the Arm, Shoulder, and Hand Index and Boston Carpal Tunnel Questionnaire at 3 months were comparable to results reported with mini-open and endoscopic release. Our results show that ultrasound-guided carpal tunnel release can be safely and effectively performed in an outpatient setting. © 2018 by the American Institute of Ultrasound in Medicine.

  1. Efficacy of Ablation Therapy for Secondary Hyperparathyroidism by Ultrasound Guided Percutaneous Thermoablation.

    Science.gov (United States)

    Zhao, Junfeng; Qian, Linxue; Zu, Yuan; Wei, Ying; Hu, Xiangdong

    2016-05-01

    The objective of this study was to explore the value of ultrasound-guided percutaneous microwave thermoablation to treat secondary hyperparathyroidism (SHPT). One hundred and thirty-eight parathyroid glands from 56 patients with SHPT were ablated in this study. All the parathyroid glands were evaluated by real-time contrast-enhanced ultrasound before, during and after ablation. Changes in serum parathyroid hormone (sPTH) levels were measured before treatment and at 1 h, 1 wk, 1 mo and 6 mo after thermoablation treatment. All 56 cases had a 1-mo follow-up, and 34 cases had a 6-mo follow-up. The sPTH level of the 54 cases 1 mo after ablation was significantly lower than that before (p 0.05). Ultrasound-guided percutaneous microwave thermoablation is a feasible and effective non-surgical alternative treatment for SHPT patients. Copyright © 2016. Published by Elsevier Inc.

  2. Feasibility of contrast-enhanced ultrasound-guided biopsy of sentinel lymph nodes in dogs.

    Science.gov (United States)

    Gelb, Hylton R; Freeman, Lynetta J; Rohleder, Jacob J; Snyder, Paul W

    2010-01-01

    Our goal was to develop and validate a technique to identify the sentinel lymph nodes of the mammary glands of healthy dogs with contrast-enhanced ultrasound, and evaluate the feasibility of obtaining representative samples of a sentinel lymph node under ultrasound guidance using a new biopsy device. Three healthy intact female adult hounds were anesthetized and each received an injection of octafluoropropane-filled lipid microspheres and a separate subcutaneous injection of methylene blue dye around a mammary gland. Ultrasound was then used to follow the contrast agent through the lymphatic channel to the sentinel lymph node. Lymph node biopsy was performed under ultrasound guidance, followed by an excisional biopsy of the lymph nodes and a regional mastectomy procedure. Excised tissues were submitted for histopathologic examination and evaluated as to whether they were representative of the node. The ultrasound contrast agent was easily visualized with ultrasound leading up to the sentinel lymph nodes. Eight normal lymph nodes (two inguinal, one axillary in two dogs; two inguinal in one dog) were identified and biopsied. Lymphoid tissue was obtained from all biopsy specimens. Samples from four of eight lymph nodes contained both cortical and medullary lymphoid tissue. Contrast-enhanced ultrasound can be successfully used to image and guide minimally invasive biopsy of the normal sentinel lymph nodes draining the mammary glands in healthy dogs. Further work is needed to evaluate whether this technique may be applicable in patients with breast cancer or other conditions warranting evaluation of sentinel lymph nodes in animals.

  3. Ultrasound guided aspiration of breast abscess as an alternative to surgical incision and drainage

    International Nuclear Information System (INIS)

    Naper, M.A.; Shaikh, M.S.; Dholia, K.R.

    2017-01-01

    To evaluate the outcome and assess the success rate of ultrasound guided aspiration of breast abscess as an alternative to surgical incision and drainage. Methodology: A prospective descriptive study was carried out at Department of Surgery, Chandka Medical College Hospital, Larkana, Pakistan, from January 2015 to December 2015. A total of 111 patients of breast abscess who underwent ultrasound guided aspiration without anesthesias with oral antibiotic cover were studied. Females with breast abscess within seven days, and the abscess size was <3cm were included in the study. Males, antibioma and inflammatory carcinoma were excluded from the study. Outcome of success or failure was observed within two weeks and recorded. Results: Out of 111 patients, 68.46% were lactating and 31.53% were non-lactating women, with ages ranging from 18 to 60 years (mean 36.5 years). The successful rate with complete resolution after ultrasound guided aspiration was observed in 94.5%. 80.82% responded after single aspiration, 12.38% after two times aspiration, and 6.66% after multiple aspirations, while 5.4% of patients required incision and drainage. Conclusion: Ultrasound guided aspiration of breast abscess is an effective treatment option with a diameter of <3cm, which can be recommended as a routine outpatient procedure. (author)

  4. Ultrasound-Guided Bipolar Umbilical Cord Occlusion in Complicated Monochorionic Pregnancies

    DEFF Research Database (Denmark)

    Schou, Katrine V; Jensen, Lisa N; Jørgensen, Connie

    2017-01-01

    INTRODUCTION: Ultrasound-guided bipolar umbilical cord occlusion (UCO) is used in complicated monochorionic multiple pregnancies in Denmark. The aim of this study was to assess a learning curve in the procedure of UCO. MATERIALS AND METHODS: One hundred and two monochorionic pregnancies treated...

  5. Distal infrared thermography and skin temperature after ultrasound-guided interscalene brachial plexus block

    DEFF Research Database (Denmark)

    Asghar, Semera; Bjerregaard, Lars S; Lundstrøm, Lars H

    2014-01-01

    thermographic imaging of the hand before and at 1 min intervals for 30 min after an ultrasound-guided IBPB with 20 ml ropivacaine 7.5 mg ml. Cooling of both hands was performed to standardise measurements. MAIN OUTCOME MEASURES: Thermographic changes in skin temperature on the dorsum of the hand. RESULTS: Forty...

  6. A clinical assessment tool for ultrasound-guided axillary brachial plexus block.

    LENUS (Irish Health Repository)

    Sultan, S F

    2012-05-01

    Competency in anesthesia traditionally has been determined subjectively in practice. Optimal training in procedural skills requires valid and reliable forms of assessment. The objective was to examine a procedure-specific clinical assessment tool for ultrasound-guided axillary brachial plexus block for inter-rater reliability and construct validity in a clinical setting.

  7. Endoscopic ultrasound-guided hepaticogastrostomy for advanced cholangiocarcinoma after failed stenting by endoscopic retrograde cholangiopancreatography

    Directory of Open Access Journals (Sweden)

    Sukij Panpimanmas

    2013-10-01

    Conclusion: Endoscopic-ultrasound-guided hepaticogastrostomy is safe and can be a good palliative option for advanced malignant biliary obstruction because it drains internally and is remote from the tumor site, promoting a long patency period of prosthesis and better quality of life.

  8. Efficacy of a single ultrasound-guided injection for the treatment of hip osteoarthritis.

    LENUS (Irish Health Repository)

    Atchia, Ismaël

    2011-01-01

    Intra-articular injection is effective for osteoarthritis, but the best single injection strategy is not known, nor are there established predictors of response. The objectives of this study were to assess and predict response to a single ultrasound-guided injection in moderate to severe hip osteoarthritis.

  9. Ultrasound-guided lateral infraclavicular block evaluated by infrared thermography and distal skin temperature

    DEFF Research Database (Denmark)

    Asghar, Semera; Lundstrøm, Lars Hyldborg; Bjerregaard, Lars Stryhn

    2014-01-01

    of the 2nd and 5th digits. METHODS: We performed an ultrasound-guided lateral infraclavicular block in 45 patients undergoing upper limb surgery. The contralateral hand served as control and we obtained infrared thermographic images of both hands before the block and during the following 30 min. We defined...

  10. Update on the role of ultrasound guided radiofrequency ablation for thyroid nodule treatment

    DEFF Research Database (Denmark)

    Radzina, Maija; Cantisani, Vito; Rauda, Madara

    2017-01-01

    Thyroid nodules can be frequently detected in general population, most of them are benign, however malignant cases are rising in the past decades. Ultrasound (US) is the most common imaging modality to assess thyroid nodular lesions, plan patient work-up and guide minimally invasive treatment...

  11. Feasibility of ultrasound-guided intraarticular contrast injection for MR arthrography

    International Nuclear Information System (INIS)

    Baek, Soo Jin; Lee, Jong Min; Kang, Duck Sick

    2005-01-01

    To assess the feasibility of ultrasound-guided intraarticular contrast injection using the posterior approach for MR arthrography. Between June 2002 and October 2004, 132 patients (29 female, 103 male: mean age, 33.6 years) underwent ultrasound-guided intraarticular contrast media injection (40 ml saline + 10 ml 2% lidocaine + 0.2 ml gadopentetate dimeglumine + 0.4 ml epinephrine) for MR arthrography. The patients were classified into four groups, viz. the no leakage group, the minor leakage with successful intraarticular injection group, the major leakage with unsuccessful intraarticular injection group, and the injection failure group. The 'no leakage' and 'minor leakage' groups were considered to be technical successes, while the 'major leakage' and 'injection failure' groups were regarded as technical failures. The technical success rate of ultrasound-guided intraarticular contrast injection using the posterior approach for MR Arthrography was 99.2% (131/132 patients) and one patients 0.7% (1/132 patients) was included in the 'major leakage' group. Ultrasound-guided intraarticular contrast injection using the posterior approach for MR arthrography was feasible with a high success rate

  12. Perioperative ultrasound-guided wire marking of calcific deposits in calcifying tendinitis of the rotator cuff.

    Science.gov (United States)

    Sigg, Andreas; Draws, Detlev; Stamm, Axel; Pfeiffer, Michael

    2011-03-01

    The identification of a calcific deposit in the rotator cuff can often cause difficulties. A new technique is described to identify the calcific deposit perioperatively with a ultrasound-guided wire. The technique allows a safe direct marking of calcific deposits making the procedure faster especially in difficult cases.

  13. Analgesic effect of ultrasound-guided transversus abdominis plane block after total abdominal hysterectomy

    DEFF Research Database (Denmark)

    Røjskjaer, Jesper O; Gade, Erik; Kiel, Louise B

    2015-01-01

    OBJECTIVE: To assess the effect of bilateral ultrasound-guided transversus abdominis plane block with ropivacaine compared with placebo as part of a multimodal analgesic regimen. DESIGN: A randomized, double-blind, placebo-controlled trial following the CONSORT criteria. SETTING: Hvidovre Univers...

  14. Indications, results, and clinical impact of endoscopic ultrasound (EUS)-guided sampling in gastroenterology

    DEFF Research Database (Denmark)

    Dumonceau, Jean-Marc; Deprez, Pierre H; Jenssen, Christian

    2017-01-01

    For pancreatic solid lesions, ESGE recommends performing endoscopic ultrasound (EUS)-guided sampling as first-line procedure when a pathological diagnosis is required. Alternatively, percutaneous sampling may be considered in metastatic disease.Strong recommendation, moderate quality evidence.In ...

  15. Value of Artisanal Simulators to Train Veterinary Students in Performing Invasive Ultrasound-Guided Procedures

    Science.gov (United States)

    Hage, Maria Cristina F. N. S.; Massaferro, Ana Beatriz; Lopes, Érika Rondon; Beraldo, Carolina Mariano; Daniel, Jéssika

    2016-01-01

    Pericardial effusion can lead to cardiac tamponade, which endangers an animal's life. Ultrasound-guided pericardiocentesis is used to remove abnormal liquid; however, it requires technical expertise. In veterinary medical education, the opportunity to teach this procedure to save lives during emergencies is rare; therefore, simulators are…

  16. Safety and Efficacy of Ultrasound-Guided Fiducial Marker Implantation for CyberKnife Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Hyun; Hong, Seong; Sook; Kim, Jung Hoon; Park, Hyun Jeong; Chang, Yun Woo; Chang, A Ram [Soonchunhyang University Seoul Hospital, Seoul (Korea, Republic of); Kwon, Seok Beom [Hallym University College of Medicine, Chuncheon (Korea, Republic of)

    2012-06-15

    To evaluate the safety and technical success rate of an ultrasound-guided fiducial marker implantation in preparation for CyberKnife radiation therapy. We retrospectively reviewed 270 percutaneous ultrasound-guided fiducial marker implantations in 77 patients, which were performed from June 2008 through March 2011. Of 270 implantations, 104 were implanted in metastatic lymph nodes, 96 were in the liver, 39 were in the pancreas, and 31 were in the prostate. During and after the implantation, major and minor procedure-related complications were documented. We defined technical success as the implantation enabling adequate treatment planning and CT simulation. The major and minor complication rates were 1% and 21%, respectively. One patient who had an implantation in the liver suffered severe abdominal pain, biloma, and pleural effusion, which were considered as major complication. Abdominal pain was the most common complication in 11 patients (14%). Among nine patients who had markers inserted in the prostate, one had transient hematuria for less than 24 hours, and the other experienced transient voiding difficulty. Of the 270 implantations, 261 were successful (97%). The reasons for unsuccessful implantations included migration of fiducial markers (five implantations, 2%) and failure to discriminate the fiducial markers (three implantations, 1%). Among the unsuccessful implantation cases, six patients required additional procedures (8%). The symptomatic complications following ultrasound-guided percutaneous implantation of fiducial markers are relatively low. However, careful consideration of the relatively higher rate of migration and discrimination failure is needed when performing ultrasound-guided percutaneous implantations of fiducial markers.

  17. Weakening Pin Bone Attachment in Fish Fillets Using High-Intensity Focused Ultrasound.

    Science.gov (United States)

    Skjelvareid, Martin H; Stormo, Svein Kristian; Þórarinsdóttir, Kristín Anna; Heia, Karsten

    2017-09-18

    High Intensity Focused Ultrasound (HIFU) can be used for the localized heating of biological tissue through the conversion of sound waves into heat. Although originally developed for human medicine, HIFU may also be used to weaken the attachment of pin bones in fish fillets to enable easier removal of such bones. This was shown in the present study, where a series of experiments were performed on HIFU phantoms and fillets of cod and salmon. In thin objects such as fish fillets, the heat is mainly dissipated at the surfaces. However, bones inside the fillet absorb ultrasound energy more efficiently than the surrounding tissue, resulting in a "self-focusing" heating of the bones. Salmon skin was found to effectively block the ultrasound, resulting in a significantly lower heating effect in fillets with skin. Cod skin partly blocked the ultrasound, but only to a small degree, enabling HIFU treatment through the skin. The treatment of fillets to reduce the pin bone attachment yielded an average reduction in the required pulling force by 50% in cod fillets with skin, with little muscle denaturation, and 72% in skinned fillets, with significant muscle denaturation. Salmon fillets were treated from the muscle side of the fillet to circumvent the need for penetration through skin. The treatment resulted in a 30% reduction in the peak pulling force and 10% reduction in the total pulling work, with a slight denaturation of the fillet surface.

  18. Ultrasound guided double injection of blood into cisterna magna: a rabbit model for treatment of cerebral vasospasm.

    Science.gov (United States)

    Chen, Yongchao; Zhu, Youzhi; Zhang, Yu; Zhang, Zixuan; Lian, Juan; Luo, Fucheng; Deng, Xuefei; Wong, Kelvin K L

    2016-02-06

    Double injection of blood into cisterna magna using a rabbit model results in cerebral vasospasm. An unacceptably high mortality rate tends to limit the application of model. Ultrasound guided puncture can provide real-time imaging guidance for operation. The aim of this paper is to establish a safe and effective rabbit model of cerebral vasospasm after subarachnoid hemorrhage with the assistance of ultrasound medical imaging. A total of 160 New Zealand white rabbits were randomly divided into four groups of 40 each: (1) manual control group, (2) manual model group, (3) ultrasound guided control group, and (4) ultrasound guided model group. The subarachnoid hemorrhage was intentionally caused by double injection of blood into their cisterna magna. Then, basilar artery diameters were measured using magnetic resonance angiography before modeling and 5 days after modeling. The depth of needle entering into cisterna magna was determined during the process of ultrasound guided puncture. The mortality rates in manual control group and model group were 15 and 23 %, respectively. No rabbits were sacrificed in those two ultrasound guided groups. We found that the mortality rate in ultrasound guided groups decreased significantly compared to manual groups. Compared with diameters before modeling, the basilar artery diameters after modeling were significantly lower in manual and ultrasound guided model groups. The vasospasm aggravated and the proportion of severe vasospasms was greater in ultrasound guided model group than that of manual group. In manual model group, no vasospasm was found in 8 % of rabbits. The ultrasound guided double injection of blood into cisterna magna is a safe and effective rabbit model for treatment of cerebral vasospasm.

  19. Lower Extremity Injury Patterns in Elite Ballet Dancers: Ultrasound/MRI Imaging Features and an Institutional Overview of Therapeutic Ultrasound Guided Percutaneous Interventions.

    Science.gov (United States)

    Rehmani, Razia; Endo, Yoshimi; Bauman, Phillip; Hamilton, William; Potter, Hollis; Adler, Ronald

    2015-10-01

    Altered biomechanics from repetitive microtrauma, such as long practice hours in en pointe (tip of the toes) or demi pointe (balls of the feet) predispose ballet dancers to a multitude of musculoskeletal pathologies particularly in the lower extremities. Both ultrasound and magnetic resonance imaging (MRI) are radiation-sparing modalities which can be used to confidently evaluate these injuries, with ultrasound (US) offering the added utility of therapeutic intervention at the same time in experienced hands. The purposes of this paper were: (1) to illustrate the US and MRI features of lower extremity injury patterns in ballet dancers, focusing on pathologies commonly encountered at a single orthopedic hospital; (2) to present complementary roles of both ultrasound and MRI in the evaluation of these injuries whenever possible; (3) to review and present our institutional approach towards therapeutic ultrasound-guided interventions by presenting explicit cases. Online searches were performed using the search criteria of "ballet biomechanics" and "ballet injuries." The results were then further narrowed down by limiting articles published in the past 15 years, modality (US and MRI), anatomical region (foot and ankle, hip and knee) and to major radiology, orthopedics, and sports medicine journals. Performing ballet poses major stress to lower extremities and predisposes dancer to several musculoskeletal injuries. These can be adequately evaluated by both US and MRI. US is useful for evaluating superficial structures such as soft tissues, tendons, and ligaments, particularly in the foot and ankle. MRI provides superior resolution of deeper structures such as joints, bone marrow, and cartilage. In addition, US can be used as a therapeutic tool for providing quick symptomatic improvement in these athletes for who "time is money". Performing ballet may cause major stress to the lower extremities, predominantly affecting the foot and ankle, followed by the knee and hip. US

  20. Effects of human hair on trans-cranial focused ultrasound efficacy in an ex-vivo cadaver model

    Science.gov (United States)

    Hananel, Arik; Snell, John W.; Kassell, Neal F.; Eames, Matthew D. C.

    2012-11-01

    Current practice before a trans-cranial MR guided Focused ultrasound procedure is shaving the patient head on treatment day. Here we present an initial attempt to evaluate the feasibility of trans-cranial FUS, in an unshaved, ex-vivo cadaver skull. We have sonicated using 220kHz and 710kHz head transducers, a cadaver skull filled with tissue mimicking phantom and covered with a wig made of human hair to evaluate feasibility of acoustic energy transfer in a full size model. Heating at focal point was measured using MR proton resonance shift thermometry. Results showed negligible effect of hair in 220kHz, and an 18% drop in temperature elevation when using 710kHz.

  1. Current status of high-intensity focused ultrasound for the management of uterine adenomyosis

    International Nuclear Information System (INIS)

    Cheng, Vincent Y. T.

    2017-01-01

    While high-intensity focused ultrasound has been used for some time in the management of uterine fibroids, its effectiveness and safety in managing adenomyosis is less well established. A literature review was performed of all eligible reports using this modality as a treatment for adenomyosis. Relevant publications were obtained from the PubMed electronic database from inception through March 2016. Eleven articles, including information from 1,150 treatments and follow-up data from 990 patients, were reviewed. High-intensity focused ultrasound appears to be effective and safe in the management of symptomatic adenomyosis, and can be considered as an alternative uterine-sparing option for women with this condition

  2. Driving Circuitry for Focused Ultrasound Noninvasive Surgery and Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Kullervo Hynynen

    2011-01-01

    Full Text Available Recent works on focused ultrasound (FUS have shown great promise for cancer therapy. Researchers are continuously trying to improve system performance, which is resulting in an increased complexity that is more apparent when using multi-element phased array systems. This has led to significant efforts to reduce system size and cost by relying on system integration. Although ideas from other fields such as microwave antenna phased arrays can be adopted in FUS, the application requirements differ significantly since the frequency range used in FUS is much lower. In this paper, we review recent efforts to design efficient power monitoring, phase shifting and output driving techniques used specifically for high intensity focused ultrasound (HIFU.

  3. Current status of high-intensity focused ultrasound for the management of uterine adenomyosis

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Vincent Y. T. [Dept. of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong (China)

    2017-04-15

    While high-intensity focused ultrasound has been used for some time in the management of uterine fibroids, its effectiveness and safety in managing adenomyosis is less well established. A literature review was performed of all eligible reports using this modality as a treatment for adenomyosis. Relevant publications were obtained from the PubMed electronic database from inception through March 2016. Eleven articles, including information from 1,150 treatments and follow-up data from 990 patients, were reviewed. High-intensity focused ultrasound appears to be effective and safe in the management of symptomatic adenomyosis, and can be considered as an alternative uterine-sparing option for women with this condition.

  4. Lysis of Chlamydomonas reinhardtii by high-intensity focused ultrasound as a function of exposure time.

    Science.gov (United States)

    Bigelow, Timothy A; Xu, Jin; Stessman, Dan J; Yao, Linxing; Spalding, Martin H; Wang, Tong

    2014-05-01

    Efficient lysis of microalgae for lipid extraction is an important concern when processing biofuels. Historically, ultrasound frequencies in the range of 10-40 kHz have been utilized for this task. However, greater efficiencies might be achievable if higher frequencies could be used. In our study, we evaluated the potential of using 1.1 MHz ultrasound to lyse microalgae for biofuel production while using Chlamydomonas reinhardtii as a model organism. The ultrasound was generated using a spherically focused transducer with a focal length of 6.34 cm and an active diameter of 6.36 cm driven by 20 cycle sine-wave tone bursts at a pulse repetition frequency of 2 kHz (3.6% duty cycle). The time-average acoustic power output was 26.2 W while the spatial-peak-pulse-average intensity (ISPPA) for each tone burst was 41 kW/cm(2). The peak compressional and rarefactional pressures at the focus were 102 and 17 MPa, respectively. The exposure time was varied for the different cases in the experiments from 5s to 9 min and cell lysis was assessed by quantifying the percentage of protein and chlorophyll release into the supernate as well as the lipid extractability. Free radical generation and lipid oxidation for the different ultrasound exposures were also determined. We found that there was a statistically significant increase in lipid extractability for all of the exposures compared to the control. The longer exposures also completely fragmented the cells releasing almost all of the protein and chlorophyll into the supernate. The cavitation activity did not significantly increase lipid oxidation while there was a minor trend of increased free radical production with increased ultrasound exposure. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Ultrasound guided pleural biopsy in undiagnosed exudative pleural effusion patients

    OpenAIRE

    Adel S. Ahmed; Mostafa I. Ragab; Alaa eldin M. Elgazaar; Nagwan A. Ismail

    2016-01-01

    Introduction: Pleural biopsy for pathological confirmation is the standard diagnostic procedure for pleural diseases, transthoracic ultrasonography (TUS) has evolved as an important imaging tool for diagnosing pleural and pulmonary conditions. Aim of the study: To assess the diagnostic yield of TUS guided pleural biopsy versus both CT guided and thoracoscopic pleural biopsy in the diagnosis of undiagnosed exudative pleural effusion. Patients and methods: The study was conducted at chest...

  6. Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU).

    Science.gov (United States)

    Grondin, Julien; Payen, Thomas; Wang, Shutao; Konofagou, Elisa E

    2015-11-03

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An oscillatory motion is generated at the focus of a 93-element and 4.5 MHz center frequency HIFU transducer by applying a 25 Hz amplitude-modulated signal using a function generator. A 64-element and 2.5 MHz imaging transducer with 68kPa peak pressure is confocally placed at the center of the HIFU transducer to acquire the radio-frequency (RF) channel data. In this protocol, real-time monitoring of thermal ablation using HIFU with an acoustic power of 7 W on canine livers in vitro is described. HIFU treatment is applied on the tissue during 2 min and the ablated region is imaged in real-time using diverging or plane wave imaging up to 1,000 frames/second. The matrix of RF channel data is multiplied by a sparse matrix for image reconstruction. The reconstructed field of view is of 90° for diverging wave and 20 mm for plane wave imaging and the data are sampled at 80 MHz. The reconstruction is performed on a Graphical Processing Unit (GPU) in order to image in real-time at a 4.5 display frame rate. 1-D normalized cross-correlation of the reconstructed RF data is used to estimate axial displacements in the focal region. The magnitude of the peak-to-peak displacement at the focal depth decreases during the thermal ablation which denotes stiffening of the tissue due to the formation of a lesion. The displacement signal-to-noise ratio (SNRd) at the focal area for plane wave was 1.4 times higher than for diverging wave showing that plane wave imaging appears to produce better displacement maps quality for HMIFU than diverging wave imaging.

  7. High-intensity focused ultrasound to treat primary hyperparathyroidism: a feasibility study in four patients

    DEFF Research Database (Denmark)

    Kovatcheva, Roussanka D; Vlahov, Jordan D; Shinkov, Alexander D

    2010-01-01

    Many patients with primary hyperparathyroidism either decline or are not candidates for surgical parathyroidectomy. There are drawbacks to medical therapy as well as percutaneous ethanol injection as alternative therapies for primary hyperparathyroidism. Therefore, in this pilot study, our aim...... was to test the feasibility, safety, and efficacy of a newly developed noninvasive high-intensity focused ultrasound (HIFU) technique for the nonsurgical management of primary hyperparathyroidism....

  8. Laser-enhanced cavitation during high intensity focused ultrasound: An in vivo study

    OpenAIRE

    Cui, Huizhong; Zhang, Ti; Yang, Xinmai

    2013-01-01

    Laser-enhanced cavitation during high intensity focused ultrasound (HIFU) was studied in vivo using a small animal model. Laser light was employed to illuminate the sample concurrently with HIFU radiation. The resulting cavitation was detected with a passive cavitation detector. The in vivo measurements were made under different combinations of HIFU treatment depths, laser wavelengths, and HIFU durations. The results demonstrated that concurrent light illumination during HIFU has the potentia...

  9. Ultrasound-guided approach for axillary brachial plexus, femoral nerve, and sciatic nerve blocks in dogs.

    Science.gov (United States)

    Campoy, Luis; Bezuidenhout, Abraham J; Gleed, Robin D; Martin-Flores, Manuel; Raw, Robert M; Santare, Carrie L; Jay, Ariane R; Wang, Annie L

    2010-03-01

    To describe an ultrasound-guided technique and the anatomical basis for three clinically useful nerve blocks in dogs. Prospective experimental trial. Four hound-cross dogs aged 2 +/- 0 years (mean +/- SD) weighing 30 +/- 5 kg and four Beagles aged 2 +/- 0 years and weighing 8.5 +/- 0.5 kg. Axillary brachial plexus, femoral, and sciatic combined ultrasound/electrolocation-guided nerve blocks were performed sequentially and bilaterally using a lidocaine solution mixed with methylene blue. Sciatic nerve blocks were not performed in the hounds. After the blocks, the dogs were euthanatized and each relevant site dissected. Axillary brachial plexus block Landmark blood vessels and the roots of the brachial plexus were identified by ultrasound in all eight dogs. Anatomical examination confirmed the relationship between the four ventral nerve roots (C6, C7, C8, and T1) and the axillary vessels. Three roots (C7, C8, and T1) were adequately stained bilaterally in all dogs. Femoral nerve block Landmark blood vessels (femoral artery and femoral vein), the femoral and saphenous nerves and the medial portion of the rectus femoris muscle were identified by ultrasound in all dogs. Anatomical examination confirmed the relationship between the femoral vessels, femoral nerve, and the rectus femoris muscle. The femoral nerves were adequately stained bilaterally in all dogs. Sciatic nerve block. Ultrasound landmarks (semimembranosus muscle, the fascia of the biceps femoris muscle and the sciatic nerve) could be identified in all of the dogs. In the four Beagles, anatomical examination confirmed the relationship between the biceps femoris muscle, the semimembranosus muscle, and the sciatic nerve. In the Beagles, all but one of the sciatic nerves were stained adequately. Ultrasound-guided needle insertion is an accurate method for depositing local anesthetic for axillary brachial plexus, femoral, and sciatic nerve blocks.

  10. Cavitation-enhanced delivery of a replicating oncolytic adenovirus to tumors using focused ultrasound.

    Science.gov (United States)

    Bazan-Peregrino, Miriam; Rifai, Bassel; Carlisle, Robert C; Choi, James; Arvanitis, Costas D; Seymour, Leonard W; Coussios, Constantin C

    2013-07-10

    Oncolytic viruses (OV) and ultrasound-enhanced drug delivery are powerful novel technologies. OV selectively self-amplify and kill cancer cells but their clinical use has been restricted by limited delivery from the bloodstream into the tumor. Ultrasound has been previously exploited for targeted release of OV in vivo, but its use to induce cavitation, microbubble oscillations, for enhanced OV tumor extravasation and delivery has not been previously reported. By identifying and optimizing the underlying physical mechanism, this work demonstrates that focused ultrasound significantly enhances the delivery and biodistribution of systemically administered OV co-injected with microbubbles. Up to a fiftyfold increase in tumor transgene expression was achieved, without any observable tissue damage. Ultrasound exposure parameters were optimized as a function of tumor reperfusion time to sustain inertial cavitation, a type of microbubble activity, throughout the exposure. Passive detection of acoustic emissions during treatment confirmed inertial cavitation as the mechanism responsible for enhanced delivery and enabled real-time monitoring of successful viral delivery. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Toward a real-time system for temporal enhanced ultrasound-guided prostate biopsy.

    Science.gov (United States)

    Azizi, Shekoofeh; Van Woudenberg, Nathan; Sojoudi, Samira; Li, Ming; Xu, Sheng; Abu Anas, Emran M; Yan, Pingkun; Tahmasebi, Amir; Kwak, Jin Tae; Turkbey, Baris; Choyke, Peter; Pinto, Peter; Wood, Bradford; Mousavi, Parvin; Abolmaesumi, Purang

    2018-03-27

    We have previously proposed temporal enhanced ultrasound (TeUS) as a new paradigm for tissue characterization. TeUS is based on analyzing a sequence of ultrasound data with deep learning and has been demonstrated to be successful for detection of cancer in ultrasound-guided prostate biopsy. Our aim is to enable the dissemination of this technology to the community for large-scale clinical validation. In this paper, we present a unified software framework demonstrating near-real-time analysis of ultrasound data stream using a deep learning solution. The system integrates ultrasound imaging hardware, visualization and a deep learning back-end to build an accessible, flexible and robust platform. A client-server approach is used in order to run computationally expensive algorithms in parallel. We demonstrate the efficacy of the framework using two applications as case studies. First, we show that prostate cancer detection using near-real-time analysis of RF and B-mode TeUS data and deep learning is feasible. Second, we present real-time segmentation of ultrasound prostate data using an integrated deep learning solution. The system is evaluated for cancer detection accuracy on ultrasound data obtained from a large clinical study with 255 biopsy cores from 157 subjects. It is further assessed with an independent dataset with 21 biopsy targets from six subjects. In the first study, we achieve area under the curve, sensitivity, specificity and accuracy of 0.94, 0.77, 0.94 and 0.92, respectively, for the detection of prostate cancer. In the second study, we achieve an AUC of 0.85. Our results suggest that TeUS-guided biopsy can be potentially effective for the detection of prostate cancer.

  12. Nonthermal ablation with microbubble-enhanced focused ultrasound close to the optic tract without affecting nerve function.

    Science.gov (United States)

    McDannold, Nathan; Zhang, Yong-Zhi; Power, Chanikarn; Jolesz, Ferenc; Vykhodtseva, Natalia

    2013-11-01

    Tumors at the skull base are challenging for both resection and radiosurgery given the presence of critical adjacent structures, such as cranial nerves, blood vessels, and brainstem. Magnetic resonance imaging-guided thermal ablation via laser or other methods has been evaluated as a minimally invasive alternative to these techniques in the brain. Focused ultrasound (FUS) offers a noninvasive method of thermal ablation; however, skull heating limits currently available technology to ablation at regions distant from the skull bone. Here, the authors evaluated a method that circumvents this problem by combining the FUS exposures with injected microbubble-based ultrasound contrast agent. These microbubbles concentrate the ultrasound-induced effects on the vasculature, enabling an ablation method that does not cause significant heating of the brain or skull. In 29 rats, a 525-kHz FUS transducer was used to ablate tissue structures at the skull base that were centered on or adjacent to the optic tract or chiasm. Low-intensity, low-duty-cycle ultrasound exposures (sonications) were applied for 5 minutes after intravenous injection of an ultrasound contrast agent (Definity, Lantheus Medical Imaging Inc.). Using histological analysis and visual evoked potential (VEP) measurements, the authors determined whether structural or functional damage was induced in the optic tract or chiasm. Overall, while the sonications produced a well-defined lesion in the gray matter targets, the adjacent tract and chiasm had comparatively little or no damage. No significant changes (p > 0.05) were found in the magnitude or latency of the VEP recordings, either immediately after sonication or at later times up to 4 weeks after sonication, and no delayed effects were evident in the histological features of the optic nerve and retina. This technique, which selectively targets the intravascular microbubbles, appears to be a promising method of noninvasively producing sharply demarcated lesions in

  13. Ultrasound-guided core needle biopsy in diagnosis of abdominal and pelvic neoplasm in pediatric patients.

    Science.gov (United States)

    Wang, Hailing; Li, Fangxuan; Liu, Juntian; Zhang, Sheng

    2014-01-01

    Ultrasound-guided core needle biopsy of abdominal and pelvic masses in adults has gained tremendous popularity. However, the application of the same treatment in children is not as popular because of apprehensions regarding inadequate tissues for the biopsy and accidental puncture of vital organs. Data of the application of ultrasound-guided core needle biopsy in 105 pediatric patients with clinically or ultrasound-diagnosed abdominopelvic masses were reviewed. Diagnostic procedures were conducted in our institution from May 2011 to May 2013. The biopsies were conducted on 86 malignant lesions and 19 benign lesions. 86 malignant tumors comprised neuroblastomas (30 cases), hepatoblastomas (15 cases), nephroblastomas (11 cases), and primitive neuroectodermal tumors/malignant small round cells (6 cases). Among malignant tumor cases, only a pelvic primitive neuroectodermal tumor did not receive a pathological diagnosis. Therefore, the biopsy accuracy was 98.8 % in malignant tumor. However, the biopsies for one neuroblastomas and one malignant small round cell tumor were inadequate for cytogenetic analysis. Therefore, 96.5 % of the malignant tumor patients received complete diagnosis via biopsy. 19 benign tumors comprised mature teratoma (10 cases), hemangioendothelioma (3 cases), paraganglioma (2 cases), and infection (2 cases). The diagnostic accuracy for benign neoplasm was 100 %. Five patients experienced postoperative complications, including pain (2 patients), bleeding from the biopsy site (2 patients), and wound infection (1 patient). Ultrasound-guided core needle biopsy is an efficient, minimally invasive, accurate, and safe diagnostic method that can be applied in the management of abdominal or pelvic mass of pediatric patients.

  14. Treatment of Partial Rotator Cuff Tear with Ultrasound-guided Platelet-rich Plasma

    Directory of Open Access Journals (Sweden)

    Vetrivel Chezian Sengodan

    2017-01-01

    Full Text Available Background: The treatment of symptomatic partial rotator cuff tear has presented substantial challenge to orthopaedic surgeons as it can vary from conservative to surgical repair. Researches have established the influence of platelet rich plasma in healing damaged tissue. Currently very few data are available regarding the evidence of clinical and radiological outcome of partial rotator cuff tear treated with ultrasound guided platelet rich plasma injection in English literature. Materials and Methods: 20 patients with symptomatic partial rotator cuff tears were treated with ultrasound guided platelet rich plasma injection. Before and after the injection of platelet rich plasma scoring was done with visual analogue score, Constant shoulder score, and UCLA shoulder score at 8 weeks and third month. A review ultrasound was performed 8 weeks after platelet rich plasma injection to assess the rotator cuff status. Results: Our study showed statistically significant improvements in 17 patients in VAS pain score, constant shoulder score and UCLA shoulder score. No significant changes in ROM were noted when matched to the contra-lateral side (P < 0.001 at the 3 month follow-up. The study also showed good healing on radiological evaluation with ultrasonogram 8 weeks after platelet rich plasma injection. Conclusion: Ultrasound guided platelet rich plasma injection for partial rotator cuff tears is an effective procedure that leads to significant decrease in pain, improvement in shoulder functions, much cost-effective and less problematic compared to a surgical treatment.

  15. Two-dimensional mapping of needle visibility with linear and curved array for ultrasound-guided interventional procedure

    Science.gov (United States)

    Susanti, Hesty; Suprijanto, Kurniadi, Deddy

    2018-02-01

    Needle visibility in ultrasound-guided technique has been a crucial factor for successful interventional procedure. It has been affected by several factors, i.e. puncture depth, insertion angle, needle size and material, and imaging technology. The influences of those factors made the needle not always well visible. 20 G needles of 15 cm length (Nano Line, facet) were inserted into water bath with variation of insertion angles and depths. Ultrasound measurements are performed with BK-Medical Flex Focus 800 using 12 MHz linear array and 5 MHz curved array in Ultrasound Guided Regional Anesthesia mode. We propose 3 criteria to evaluate needle visibility, i.e. maximum intensity, mean intensity, and the ratio between minimum and maximum intensity. Those criteria were then depicted into representative maps for practical purpose. The best criterion candidate for representing the needle visibility was criterion 1. Generally, the appearance pattern of the needle from this criterion was relatively consistent, i.e. for linear array, it was relatively poor visibility in the middle part of the shaft, while for curved array, it is relatively better visible toward the end of the shaft. With further investigations, for example with the use of tissue-mimicking phantom, the representative maps can be built for future practical purpose, i.e. as a tool for clinicians to ensure better needle placement in clinical application. It will help them to avoid the "dead" area where the needle is not well visible, so it can reduce the risks of vital structures traversing and the number of required insertion, resulting in less patient morbidity. Those simple criteria and representative maps can be utilized to evaluate general visibility patterns of the needle in vast range of needle types and sizes in different insertion media. This information is also important as an early investigation for future research of needle visibility improvement, i.e. the development of beamforming strategies and

  16. Ultrasound-guided truncal blocks: A new frontier in regional anaesthesia

    Directory of Open Access Journals (Sweden)

    Arunangshu Chakraborty

    2016-01-01

    Full Text Available The practice of regional anaesthesia is rapidly changing with the introduction of ultrasound into the working domain of the anaesthesiologist. New techniques are being pioneered. Among the recent techniques, notable are the truncal blocks, for example, the transversus abdominis plane block, rectus sheath block, hernia block and quadratus lumborum block in the abdomen and the pectoral nerves (Pecs block 1 and 2, serratus anterior plane block and intercostal nerve block. This narrative review covers the brief anatomical discourse along with technical description of the ultrasound-guided truncal blocks.

  17. The clinical value of trans-vaginal ultrasound-guided puncture in the treatment of pelvic abscess

    International Nuclear Information System (INIS)

    Wang Ping; Gong Wei

    2008-01-01

    Objective: To investigate the clinical value of trans-vaginal ultrasound-guided (TVS) puncture in the treatment of pelvic abscess. Methods 30 cases with pelvic abscess were treated by transvaginal ultrasound-guided puncture. The long-dated effects were followed-up. Results: 29 cases were cured by TVS puncture. Operation was performed in 1 patient because of invalid effect. The cure rate was 97%. Conclusion: Ultrasound-guided puncture is a safe and convenient method in the treatment of pelvic abscess. (authors)

  18. Ultrasound-Guided 50% Ethyl Alcohol Injection for Patients With Malleolar and Olecranon Bursitis: A Prospective Pilot Study

    Science.gov (United States)

    Hong, Ji Seong; Lee, Jin Hyung

    2016-01-01

    Objective To evaluate the feasibility and effect of ultrasound-guided ethyl alcohol injection on malleolar and olecranon synovial proliferative bursitis. Methods Twenty-four patients received ultrasound-guided 50% diluted ethyl alcohol injection at the site of synovial proliferative bursitis after aspiration of the free fluid. Results Swelling and symptoms significantly decreased in 13 of the 24 patients without any complications. Eleven patients had partial improvement in swelling and symptoms. Conclusion Ultrasound-guided alcohol injection could be an alternative therapeutic option before surgery in patients with chronic intractable malleolar and olecranon synovial proliferative bursitis. PMID:27152282

  19. Fluoroscopy- vs ultrasound-guided aspiration techniques in the management of periprosthetic joint infection: which is the best?

    Science.gov (United States)

    Randelli, Filippo; Brioschi, Marco; Randelli, Pietro; Ambrogi, Federico; Sdao, Silvana; Aliprandi, Alberto

    2018-01-01

    Fluid samples obtained from an affected joint still play a central role in the diagnosis of periprosthetic joint infection (PJI). It is the only preoperative test able to discover the causative microbiological agent. In the hip, fluid aspiration can be performed through fluoroscopy, ultrasound, or, less commonly, computed tomography. However, there is still a lack of consensus on which method is preferable in terms of efficacy and costbenefit. We, therefore, asked whether (1) the benefits in terms of sensitivity and specificity and (2) the costs were comparable between fluoroscopy- and ultrasound-guided joint aspirations in a suspicious of hip PJI. Between 2013 and 2016, 52 hip aspirations were performed on 49 patients with clinical, radiological, or serological suspicion of PJI, waiting for a revision surgery. The patients were divided in two groups: fluoroscopy- (n = 26) vs ultrasound-guided hip aspiration group (n = 26). These groups were also divided in control and infected patients. The criteria of MusculoSkeletal Infection Society (MSIS) were used, as gold standard, to define PJI. (1) Ultrasound-guided aspiration revealed valid sensitivity (89% vs 60%) and specificity (94% vs 81%) in comparison with fluoroscopic-guided aspiration. (2) The cost analysis was also in favor of ultrasound-guided aspiration (125.30€) than fluoroscopic-guided aspiration (343.58€). We concluded that ultrasound-guided hip aspiration could represent a valid, safe, and less expensive diagnostic alternative to fluoroscopic-guided aspiration in hip PJI.

  20. General Ultrasound Imaging

    Medline Plus

    Full Text Available ... inserted into a man's rectum to view the prostate. Transvaginal ultrasound. The transducer is inserted into a ... Stenting Ultrasound-Guided Breast Biopsy Obstetric Ultrasound Ultrasound - Prostate Biopsies - Overview Images related to General Ultrasound Videos ...

  1. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    International Nuclear Information System (INIS)

    Zhou Xiaodong; Ren Xiaolong; Zhang Jun; He Guangbin; Zheng Minjuan; Tian Xue; Li Li; Zhu Ting; Zhang Min; Wang Lei; Luo Wen

    2007-01-01

    Purpose: To assess the utility of contrast-enhanced ultrasonography (ceUS) in the assessment of the therapeutic response to high intensity focused ultrasound (HIFU) ablation in patients with uterine fibroid. Materials and methods: Sixty-four patients with a total of 64 uterine fibroids (mean: 5.3 ± 1.2 cm; range: 3.2-8.9 cm) treated with HIFU ablation under the ultrasound guidance were evaluated with ceUS after receiving an intravenous bolus injection of a microbubble contrast agent (SonoVue) within 1 week after intervention. We obtained serial ceUS images during the time period from beginning to 5 min after the initiation of the bolus contrast injection. All of the patients underwent a contrast enhanced MRI (ceMRI) and ultrasound guided needle puncture biopsy within 1 week after HIFU ablation. And as a follow-up, all of the patients underwent US at 1, 3, 6 and 12 months after HIFU treatment. The volume change was observed and compared to pre- and post-HIFU ablation. The results of the ceUS were compared with those of the ceMRI in terms of the presence or absence of residual unablated tumor and pathologic change in the treated lesions. Results: On ceUS, diagnostic accuracy was 100%, while residual unablated tumors were found in three uterine fibroids (4.7%) and failed treatment was found in eight uterine fibroids (12.5%). All the 11 fibroids were subjected to additional HIFU ablation. Of the 58 ablated fibroids without residual tumors on both the ceUS and ceMRI after the HIFU ablation, the volumes of all the fibroids decreased in different degrees during the 1 year follow-up USs. And histologic examinations confirmed findings of necrotic and viable tumor tissue, respectively. Conclusion: CEUS is potentially useful for evaluating the early therapeutic effect of percutaneous HIFU ablation for uterine fibroids

  2. Effect of focused ultrasound stimulation at different ultrasonic power levels on the local field potential power spectrum

    International Nuclear Information System (INIS)

    Yuan Yi; Lu Cheng-Biao; Li Xiao-Li

    2015-01-01

    Local field potential (LFP) signals of the rat hippocampus were recorded under noninvasive focused ultrasound stimulation (FUS) with different ultrasonic powers. The LFP mean absolute power was calculated with the Welch algorithm at the delta, theta, alpha, beta, and gamma frequency bands. The experimental results demonstrate that the LFP mean absolute power at different frequency bands increases as the ultrasound power increases. (paper)

  3. Drug Release from Phase-Changeable Nanodroplets Triggered by Low-Intensity Focused Ultrasound

    Science.gov (United States)

    Cao, Yang; Chen, Yuli; Yu, Tao; Guo, Yuan; Liu, Fengqiu; Yao, Yuanzhi; Li, Pan; Wang, Dong; Wang, Zhigang; Chen, Yu; Ran, Haitao

    2018-01-01

    Background: As one of the most effective triggers with high tissue-penetrating capability and non-invasive feature, ultrasound shows great potential for controlling the drug release and enhancing the chemotherapeutic efficacy. In this study, we report, for the first time, construction of a phase-changeable drug-delivery nanosystem with programmable low-intensity focused ultrasound (LIFU) that could trigger drug-release and significantly enhance anticancer drug delivery. Methods: Liquid-gas phase-changeable perfluorocarbon (perfluoropentane) and an anticancer drug (doxorubicin) were simultaneously encapsulated in two kinds of nanodroplets. By triggering LIFU, the nanodroplets could be converted into microbubbles locally in tumor tissues for acoustic imaging and the loaded anticancer drug (doxorubicin) was released after the microbubble collapse. Based on the acoustic property of shell materials, such as shell stiffness, two types of nanodroplets (lipid-based nanodroplets and PLGA-based nanodroplets) were activated by different acoustic pressure levels. Ultrasound irradiation duration and power of LIFU were tested and selected to monitor and control the drug release from nanodroplets. Various ultrasound energies were introduced to induce the phase transition and microbubble collapse of nanodroplets in vitro (3 W/3 min for lipid nanodroplets; 8 W/3 min for PLGA nanodroplets). Results: We detected three steps in the drug-releasing profiles exhibiting the programmable patterns. Importantly, the intratumoral accumulation and distribution of the drug with LIFU exposure were significantly enhanced, and tumor proliferation was substantially inhibited. Co-delivery of two drug-loaded nanodroplets could overcome the physical barriers of tumor tissues during chemotherapy. Conclusion: Our study provides a new strategy for the efficient ultrasound-triggered chemotherapy by nanocarriers with programmable LIFU capable of achieving the on-demand drug release. PMID:29507623

  4. Analysis of "dry" mesothelioma with ultrasound guided biopsies

    NARCIS (Netherlands)

    Stigt, Jos A.; Boers, James E.; Groen, Harry J. M.

    2012-01-01

    Background: Image-guided sampling of the thickened pleura is a sensitive approach in patients with malignant pleural mesothelioma with pleural effusion. Malignant pleural mesothelioma presenting without effusion however is more of a diagnostic challenge. In this study we report the diagnostic yield

  5. Non-invasive peripheral nerve stimulation via focused ultrasound in vivo

    Science.gov (United States)

    Downs, Matthew E.; Lee, Stephen A.; Yang, Georgiana; Kim, Seaok; Wang, Qi; Konofagou, Elisa E.

    2018-02-01

    Focused ultrasound (FUS) has been employed on a wide range of clinical applications to safely and non-invasively achieve desired effects that have previously required invasive and lengthy procedures with conventional methods. Conventional electrical neuromodulation therapies that are applied to the peripheral nervous system (PNS) are invasive and/or non-specific. Recently, focused ultrasound has demonstrated the ability to modulate the central nervous system and ex vivo peripheral neurons. Here, for the first time, noninvasive stimulation of the sciatic nerve eliciting a physiological response in vivo is demonstrated with FUS. FUS was applied on the sciatic nerve in mice with simultaneous electromyography (EMG) on the tibialis anterior muscle. EMG signals were detected during or directly after ultrasound stimulation along with observable muscle contraction of the hind limb. Transecting the sciatic nerve downstream of FUS stimulation eliminated EMG activity during FUS stimulation. Peak-to-peak EMG response amplitudes and latency were found to be comparable to conventional electrical stimulation methods. Histology along with behavioral and thermal testing did not indicate damage to the nerve or surrounding regions. The findings presented herein demonstrate that FUS can serve as a targeted, safe and non-invasive alternative to conventional peripheral nervous system stimulation to treat peripheral neuropathic diseases in the clinic.

  6. Bifurcation of ensemble oscillations and acoustic emissions from early stage cavitation clouds in focused ultrasound

    International Nuclear Information System (INIS)

    Gerold, Bjoern; Prentice, Paul; Rachmilevitch, Itay

    2013-01-01

    The acoustic emissions from single cavitation clouds at an early stage of development in 0.521 MHz focused ultrasound of varying intensity, are detected and directly correlated to high-speed microscopic observations, recorded at 1 × 10 6 frames per second. At lower intensities, a stable regime of cloud response is identified whereby bubble-ensembles exhibit oscillations at half the driving frequency, which is also detected in the acoustic emission spectra. Higher intensities generate clouds that develop more rapidly, with increased nonlinearity evidenced by a bifurcation in the frequency of ensemble response, and in the acoustic emissions. A single bubble oscillation model is subject to equivalent ultrasound conditions and fitted to features in the hydrophone and high-speed spectral data, allowing an effective quiescent radius to be inferred for the clouds that evolve at each intensity. The approach indicates that the acoustic emissions originate from the ensemble dynamics and that the cloud acts as a single bubble of equivalent radius in terms of the scattered field. Jetting from component cavities on the periphery of clouds is regularly observed at higher intensities. The results may be of relevance for monitoring and controlling cavitation in therapeutic applications of focused ultrasound, where the phenomenon has the potential to mediate drug delivery from vasculature. (paper)

  7. High-Intensity Focused Ultrasound (HIFU) in Localized Prostate Cancer Treatment

    International Nuclear Information System (INIS)

    Alkhorayef, Mohammed; Mahmoud, Mustafa Z.; Alzimami, Khalid S.; Sulieman, Abdelmoneim; Fagiri, Maram A.

    2015-01-01

    High-intensity focused ultrasound (HIFU) applies high-intensity focused ultrasound energy to locally heat and destroy diseased or damaged tissue through ablation. This study intended to review HIFU to explain the fundamentals of HIFU, evaluate the evidence concerning the role of HIFU in the treatment of prostate cancer (PC), review the technologies used to perform HIFU and the published clinical literature regarding the procedure as a primary treatment for PC. Studies addressing HIFU in localized PC were identified in a search of internet scientific databases. The analysis of outcomes was limited to journal articles written in English and published between 2000 and 2013. HIFU is a non-invasive approach that uses a precisely delivered ultrasound energy to achieve tumor cell necrosis without radiation or surgical excision. In current urological oncology, HIFU is used clinically in the treatment of PC. Clinical research on HIFU therapy for localized PC began in the 1990s, and the majority of PC patients were treated with the Ablatherm device. HIFU treatment for localized PC can be considered as an alternative minimally invasive therapeutic modality for patients who are not candidates for radical prostatectomy. Patients with lower pre-HIFU PSA level and favourable pathologic Gleason score seem to present better oncologic outcomes. Future advances in technology and safety will undoubtedly expand the HIFU role in this indication as more of patient series are published, with a longer follow-up period

  8. High Intensity Focused Ultrasound for Cancer Therapy--harnessing its non-linearity

    International Nuclear Information System (INIS)

    Haar, Gail ter

    2008-01-01

    In medicine in general, and for cancer treatments in particular, there is a drive to find effective non-invasive therapies. High Intensity Focused Ultrasound (HIFU) represents one such technique. In principle, it is simple--a high energy ultrasound beam is brought to a tight focus within a target which may lie several centimetres below the skin surface (for example, in a tumour of the liver), and is used to destroy a selected tissue volume. The main mechanism for cell killing in a HIFU beam is heat. Ultrasound energy absorption is frequency dependent, the higher frequencies being absorbed most strongly. Significant thermal advantage may therefore be gained from non-linear propagation, which generates higher harmonics, in tissue. Acoustic cavitation and thermal exsolution of gas (boiling) also contribute to tissue damage. This activity leads to the local mechanical disruption of cells. In addition, the non-linear oscillation of these bubbles leads to enhanced energy deposition. The acoustic emissions from such bubbles are characteristic of their behaviour and may be correlated to some extent with the appearance of the disruption produced. The more widespread clinical acceptance of HIFU is awaiting faster, and more efficient, energy delivery and treatment monitoring. A better understanding of the nonlinear aspects of HIFU propagation in tissue is thus important if this technique is to benefit more patients

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

    International Nuclear Information System (INIS)

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

    2000-01-01

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

  10. Combined passive acoustic mapping and magnetic resonance thermometry for monitoring phase-shift nanoemulsion enhanced focused ultrasound therapy

    Science.gov (United States)

    Crake, Calum; Meral, F. Can; Burgess, Mark T.; Papademetriou, Iason T.; McDannold, Nathan J.; Porter, Tyrone M.

    2017-08-01

    Focused ultrasound (FUS) has the potential to enable precise, image-guided noninvasive surgery for the treatment of cancer in which tumors are identified and destroyed in a single integrated procedure. However, success of the method in highly vascular organs has been limited due to heat losses to perfusion, requiring development of techniques to locally enhance energy absorption and heating. In addition, FUS procedures are conventionally monitored using MRI, which provides excellent anatomical images and can map temperature, but is not capable of capturing the full gamut of available data such as the acoustic emissions generated during this inherently acoustically-driven procedure. Here, we employed phase-shift nanoemulsions (PSNE) embedded in tissue phantoms to promote cavitation and hence temperature rise induced by FUS. In addition, we incorporated passive acoustic mapping (PAM) alongside simultaneous MR thermometry in order to visualize both acoustic emissions and temperature rise, within the bore of a full scale clinical MRI scanner. Focal cavitation of PSNE could be resolved using PAM and resulted in accelerated heating and increased the maximum elevated temperature measured via MR thermometry compared to experiments without nanoemulsions. Over time, the simultaneously acquired acoustic and temperature maps show translation of the focus of activity towards the FUS transducer, and the magnitude of the increase in cavitation and focal shift both increased with nanoemulsion concentration. PAM results were well correlated with MRI thermometry and demonstrated greater sensitivity, with the ability to detect cavitation before enhanced heating was observed. The results suggest that PSNE could be beneficial for enhancement of thermal focused ultrasound therapies and that PAM could be a critical tool for monitoring this process.

  11. Ultrasound

    Science.gov (United States)

    Ultrasound is a useful procedure for monitoring the baby's development in the uterus. Ultrasound uses inaudible sound waves to produce a two-dimensional image of the baby while inside the mother's ...

  12. Ultrasound-Guided Angioplasty of Dysfunctional Vascular Access for Haemodialysis. The Pros and Cons

    Energy Technology Data Exchange (ETDEWEB)

    García-Medina, J., E-mail: josegmedina57@gmail.com [“Reina Sofia” University Hospital, Vascular and Interventional Radiology Unit, Department of Radiology (Spain); García-Alfonso, J. J., E-mail: juanjozarandieta@gmail.com [University of Murcia, Faculty of Medicine (Spain)

    2017-05-15

    PurposeTo describe the benefits and the disadvantages of angioplasty in dialysis fistulas using only ultrasound guidance.Materials and MethodsThis is a prospective study in 132 failing or non-maturing arteriovenous accesses that underwent 189 ultrasound-guided balloon angioplasties. The technical success was defined as non-use of X-ray fluoroscopy during the procedure.Results127 procedures (67%) were successfully completed without fluoroscopy. Most failures were due to difficulty to traverse aneurismal segments, as well as anastomotic stenoses. Including initial failures, the primary patency rates at 6, 12 months and 2 years were 75 ± 3, 41 ± 3 and 14 ± 2%, respectively.ConclusionEndovascular repair of the dysfunctional vascular access for haemodialysis under ultrasound guidance is feasible and safe in roughly two-thirds of cases.

  13. Technical guide to evaluate upper limb joints (shoulder, elbow and wrist) by ultrasound

    International Nuclear Information System (INIS)

    Obregon Baez, Luis Rafael

    2014-01-01

    A guideline to follow is offered to radiologists and residents of radiology service of medical imaging, when evaluating by ultrasound the shoulder joints, elbow, wrist. The importance to performing of musculoskeletal ultrasound by its pathology variable is established. The use of appropriate equipment and effective application of the techniques exposed of echography exploration have made enable the valuation of many pathologies with high sensitivity and specificity. The echography has been the musculoskeletal imaging technique that more rapidly has evolved. Currently, this technique has been replaced by magnetic resonance imaging in various clinical fields and also serves as a complement to other techniques. Exposed techniques have been of great benefit for radiologists medical and residents, obtaining with its use a quick guide for the realization of upper limb musculoskeletal ultrasounds. The appropriate and easy techniques are better known for the evaluation of these structures, and so document both sports injuries, as joint and rheumatic diseases [es

  14. Derivation of a Performance Checklist for Ultrasound-Guided Arthrocentesis Using the Modified Delphi Method.

    Science.gov (United States)

    Kunz, Derek; Pariyadath, Manoj; Wittler, Mary; Askew, Kim; Manthey, David; Hartman, Nicholas

    2017-06-01

    Arthrocentesis is an important skill for physicians in multiple specialties. Recent studies indicate a superior safety and performance profile for this procedure using ultrasound guidance for needle placement, and improving quality of care requires a valid measurement of competency using this modality. We endeavored to create a validated tool to assess the performance of this procedure using the modified Delphi technique and experts in multiple disciplines across the United States. We derived a 22-item checklist designed to assess competency for the completion of ultrasound-guided arthrocentesis, which demonstrated a Cronbach's alpha of 0.89, indicating an excellent degree of internal consistency. Although we were able to demonstrate content validity for this tool, further validity evidence should be acquired after the tool is used and studied in clinical and simulated contexts. © 2017 by the American Institute of Ultrasound in Medicine.

  15. Prediction of thermal coagulation from the instantaneous strain distribution induced by high-intensity focused ultrasound

    Science.gov (United States)

    Iwasaki, Ryosuke; Takagi, Ryo; Tomiyasu, Kentaro; Yoshizawa, Shin; Umemura, Shin-ichiro

    2017-07-01

    The targeting of the ultrasound beam and the prediction of thermal lesion formation in advance are the requirements for monitoring high-intensity focused ultrasound (HIFU) treatment with safety and reproducibility. To visualize the HIFU focal zone, we utilized an acoustic radiation force impulse (ARFI) imaging-based method. After inducing displacements inside tissues with pulsed HIFU called the push pulse exposure, the distribution of axial displacements started expanding and moving. To acquire RF data immediately after and during the HIFU push pulse exposure to improve prediction accuracy, we attempted methods using extrapolation estimation and applying HIFU noise elimination. The distributions going back in the time domain from the end of push pulse exposure are in good agreement with tissue coagulation at the center. The results suggest that the proposed focal zone visualization employing pulsed HIFU entailing the high-speed ARFI imaging method is useful for the prediction of thermal coagulation in advance.

  16. Reduced clot debris size using standing waves formed via high intensity focused ultrasound

    Science.gov (United States)

    Guo, Shifang; Du, Xuan; Wang, Xin; Lu, Shukuan; Shi, Aiwei; Xu, Shanshan; Bouakaz, Ayache; Wan, Mingxi

    2017-09-01

    The feasibility of utilizing high intensity focused ultrasound (HIFU) to induce thrombolysis has been demonstrated previously. However, clinical concerns still remain related to the clot debris produced via fragmentation of the original clot potentially being too large and hence occluding downstream vessels, causing hazardous emboli. This study investigates the use of standing wave fields formed via HIFU to disintegrate the thrombus while achieving a reduced clot debris size in vitro. The results showed that the average diameter of the clot debris calculated by volume percentage was smaller in the standing wave mode than in the travelling wave mode at identical ultrasound thrombolysis settings. Furthermore, the inertial cavitation dose was shown to be lower in the standing wave mode, while the estimated cavitation bubble size distribution was similar in both modes. These results show that a reduction of the clot debris size with standing waves may be attributed to the particle trapping of the acoustic potential well which contributed to particle fragmentation.

  17. Ultrasound line-by-line scanning method of spatial-temporal active cavitation mapping for high-intensity focused ultrasound.

    Science.gov (United States)

    Ding, Ting; Zhang, Siyuan; Fu, Quanyou; Xu, Zhian; Wan, Mingxi

    2014-01-01

    This paper presented an ultrasound line-by-line scanning method of spatial-temporal active cavitation mapping applicable in a liquid or liquid filled tissue cavities exposed by high-intensity focused ultrasound (HIFU). Scattered signals from cavitation bubbles were obtained in a scan line immediately after one HIFU exposure, and then there was a waiting time of 2 s long enough to make the liquid back to the original state. As this pattern extended, an image was built up by sequentially measuring a series of such lines. The acquisition of the beamformed radiofrequency (RF) signals for a scan line was synchronized with HIFU exposure. The duration of HIFU exposure, as well as the delay of the interrogating pulse relative to the moment while HIFU was turned off, could vary from microseconds to seconds. The feasibility of this method was demonstrated in tap-water and a tap-water filled cavity in the tissue-mimicking gelatin-agar phantom as capable of observing temporal evolutions of cavitation bubble cloud with temporal resolution of several microseconds, lateral and axial resolution of 0.50 mm and 0.29 mm respectively. The dissolution process of cavitation bubble cloud and spatial distribution affected by cavitation previously generated were also investigated. Although the application is limited by the requirement for a gassy fluid (e.g. tap water, etc.) that allows replenishment of nuclei between HIFU exposures, the technique may be a useful tool in spatial-temporal cavitation mapping for HIFU with high precision and resolution, providing a reference for clinical therapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Endoscopic Ultrasound-guided Drainage of Pancreatic Pseudocysts

    DEFF Research Database (Denmark)

    Ng, Pui Yung; Nytoft Rasmussen, Ditlev; Vilmann, Peter

    2013-01-01

    or by telephonic interview. RESULTS: A total of 61 procedures were performed. The symptoms that indicated drainage were abdominal pain (n = 43), vomiting (n = 7) and jaundice (n = 5). The procedure was technically successful in 57 of the 61 procedures (93%). The immediate complication rate was 5%. At a mean follow......-up of 45 weeks, the treatment success was 75%. The medium term complications appeared in 25% of cases, which included three cases each of stent clogging, stent migration, infection and six cases of recurrence. There was no mortality. CONCLUSION: EUS-guided drainage is an effective treatment for PPC...... with a successful outcome in most of patients. Most of the complications require minimal invasive surgical treatment or repeated EUS-guided drainage procedures....

  19. Evaluation of a Standardized Program for Training Practicing Anesthesiologists in Ultrasound-Guided Regional Anesthesia Skills.

    Science.gov (United States)

    Mariano, Edward R; Harrison, T Kyle; Kim, T Edward; Kan, Jack; Shum, Cynthia; Gaba, David M; Ganaway, Toni; Kou, Alex; Udani, Ankeet D; Howard, Steven K

    2015-10-01

    Practicing anesthesiologists have generally not received formal training in ultrasound-guided perineural catheter insertion. We designed this study to determine the efficacy of a standardized teaching program in this population. Anesthesiologists in practice for 10 years or more were recruited and enrolled to participate in a 1-day program: lectures and live-model ultrasound scanning (morning) and faculty-led iterative practice and mannequin-based simulation (afternoon). Participants were assessed and recorded while performing ultrasound-guided perineural catheter insertion at baseline, at midday (interval), and after the program (final). Videos were scored by 2 blinded reviewers using a composite tool and global rating scale. Participants were surveyed every 3 months for 1 year to report the number of procedures, efficacy of teaching methods, and implementation obstacles. Thirty-two participants were enrolled and completed the program; 31 of 32 (97%) completed the 1-year follow-up. Final scores [median (10th-90th percentiles)] were 21.5 (14.5-28.0) of 30 points compared to 14.0 (9.0-20.0) at interval (P < .001 versus final) and 12.0 (8.5-17.5) at baseline (P < .001 versus final), with no difference between interval and baseline. The global rating scale showed an identical pattern. Twelve of 26 participants without previous experience performed at least 1 perineural catheter insertion after training (P < .001). However, there were no differences in the monthly average number of procedures or complications after the course when compared to baseline. Practicing anesthesiologists without previous training in ultrasound-guided regional anesthesia can acquire perineural catheter insertion skills after a 1-day standardized course, but changing clinical practice remains a challenge. © 2015 by the American Institute of Ultrasound in Medicine.

  20. The role of ultrasound guided percutaneous needle aspiration and lavage (barbotage in the treatment of calcific tendinitis

    Directory of Open Access Journals (Sweden)

    Gamal Niazi

    2015-03-01

    Conclusion: Ultrasound guided aspiration and lavage (barbotage is a highly effective, less aggressive method of treatment in cases of calcific tendinosis, especially for cases with severe pain that does not respond to other conservative methods.

  1. Comparative study between ultrasound guided tap block and paravertebral block in upper abdominal surgeries. Randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ruqaya M. Elsayed

    2017-01-01

    Conclusion: We concluded that ultrasound guided transversus abdominis plane block and thoracic paravertebral block were safe and effective anesthetic technique for upper abdominal surgery with longer and potent postoperative analgesia in thoracic paravertebral block than transversus abdominis block.

  2. Ultrasound-guided supra-acetabular pin placement in pelvic external fixation: description of a surgical technique and results.

    Science.gov (United States)

    Chana-Rodríguez, Francisco; Cuervas-Mons, Manuel; Rojo-Manaute, José; Mora, Félix; Arnal, Juan; Vaquero-Martín, Javier

    2017-11-01

    Pelvic fracture in trauma patients can lead to hemodynamic instability. External fixation is a treatment capable of stabilizing these injuries in the context of damage control surgery. Supra-acetabular pin offers the greater biomechanical stability but requires the use of intraoperative fluoroscopy. The aim of this study was to analyze our results for an ultrasound-guided supra-acetabular pinning. Cross-sectional study with cadaveric specimens. Ultrasound-guided pin placement assessed by fluoroscopy and dissection. Fourteen ultrasound-guided supra-acetabular pins were placed in seven cadaveric specimens. Excellent placement in all cases, evaluated with radiological control. Good qualitative bone fixation after dissection. One femoral cutaneous nerve was not found during anatomic dissection and was assumed injured. Ultrasound-guided supra-acetabular pin placement is a feasible and effective technique. Our study indicates that pin placement without intraoperative fluoroscopy is feasible without compromising the reliability of its placement. © 2017 Elsevier Ltd. All rights reserved.

  3. The Usefulness of Intensivist-Performed Bedside Drainage of Pleural Effusion via Ultrasound-Guided Pigtail Catheter

    Directory of Open Access Journals (Sweden)

    Joo Won Min

    2014-08-01

    CONCLUSIONS: Intensivist-performed bedside drainage of pleural effusion via ultrasound (US-guided pigtail catheter is useful and safe and may be recommended in some patients in an intensive care unit.

  4. Compensated Row-Column Ultrasound Imaging System Using Multilayered Edge Guided Stochastically Fully Connected Random Fields.

    Science.gov (United States)

    Ben Daya, Ibrahim; Chen, Albert I H; Shafiee, Mohammad Javad; Wong, Alexander; Yeow, John T W

    2017-09-06

    The row-column method received a lot of attention for 3-D ultrasound imaging. By reducing the number of connections required to address the 2-D array and therefore reducing the amount of data to handle, this addressing method allows for real time 3-D imaging. Row-column still has its limitations: the issues of sparsity, speckle noise inherent to ultrasound, the spatially varying point spread function, and the ghosting artifacts inherent to the row-column method must all be taken into account when building a reconstruction framework. In this research, we build on a previously published system and propose an edge-guided, compensated row-column ultrasound imaging system that incorporates multilayered edge-guided stochastically fully connected conditional random fields to address the limitations of the row-column method. Tests carried out on simulated and real row-column ultrasound images show the effectiveness of our proposed system over other published systems. Visual assessment show our proposed system's potential at preserving edges and reducing speckle. Quantitative analysis shows that our proposed system outperforms previously published systems when evaluated with metrics such as Peak Signal-to-Noise Ratio, Coefficient of Correlation, and Effective Number of Looks. These results show the potential of our proposed system as an effective tool for enhancing 3-D row-column imaging.

  5. Point-of-Care Ultrasound-Guided Percutaneous Cannulation of Extracorporeal Membrane Oxygenation: Make it Simple.

    Science.gov (United States)

    Ahn, Hong Joon; Lee, Jun Wan; Joo, Ki Hyuk; You, Yeon Ho; Ryu, Seung; Lee, Jin Woong; Kim, Seung Whan

    2017-12-30

    Cannulation of the great vessels is required for extracorporeal membrane oxygenation (ECMO). Currently, there is no guideline for optimal imaging modalities during percutaneous cannulation of ECMO. The purpose of this study was to describe percutaneous cannulation guided by point-of-care ultrasound (POCUS) for ECMO and compare it with fluoroscopy and landmark guidance. Three groups (POCUS-, fluoroscopy-, and landmark-guided) of percutaneous cannulation for ECMO were analyzed retrospectively in a tertiary academic hospital. In the POCUS-guided group, visual confirmation of guidewire and cannula by ultrasound in both the access and return cannula were essential for successful cannulation. Fluoroscopy- and landmark-guided groups were cannulated with the conventional technique. A total of 128 patients were treated by ECMO during the study period, of which 94 (73.4%) cases were venoarterial ECMO. This included 56 cases of extracorporeal cardiopulmonary resuscitation. Also, there were 30 (23.4%) cases of venovenous ECMO and 4 (3.1%) cases of venoarteriovenous ECMO. A total of 71 (55.5%) patients were cannulated under POCUS guidance, and 43 (33.6%) patients were cannulated under fluoroscopy guidance and 14 (10.9%) patients were cannulated by landmark guidance. No surgical cut downs were required. Misplacement of cannula occurred in 3 (2.3%) cases. All three occurred in the landmark-guided group. POCUS-guided cannulation is comparable to fluoroscopy-guided cannulation in terms of avoiding cannula misplacement. In our experience, POCUS-guided cannulation is a useful strategy over fluoroscopy- and landmark-guided cannulation during peripheral ECMO. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Ultrasound-Guided Percutaneous Drainage of Neonatal Pyometrocolpos Under Local Anesthesia

    International Nuclear Information System (INIS)

    Algin, Oktay; Erdogan, Cuneyt; Kilic, Nizamettin

    2011-01-01

    Hydrometrocolpos is an uncommon congenital disorder with cystic dilatation of the vagina and uterus that occurs as a result of accumulated secretions from the reproductive tract due to distal genital tract obstruction. Secondary infection may also occur, resulting in pyometrocolpos, a potentially lethal disease. Immediate drainage of the cystic mass in patients determined to have pyometrocolpos is required to prevent or treat uropathy and septicemia until definitive corrective surgery can be performed. We report an unusual cause of obstructive uropathy in three infants: pyometrocolpos due to lower genital tract atresia. Ultrasound-guided percutaneous drainage of the pyometrocolpos resulted in dramatically improved clinical and laboratory findings in these patients. Ultrasound-guided percutaneous drainage under local anesthesia is a simple, minimally invasive, safe, and effective procedure that facilitates later successful corrective surgery and avoids the need for more complex drainage procedures.

  7. Ultrasound-Guided Drainage of Supralevator Hematoma in a Hemodynamically Stable Patient.

    Science.gov (United States)

    Mukhopadhyay, Debjani; Jennings, Paul E; Banerjee, Mamta; Gada, Ruta

    2015-12-01

    Paravaginal hematomas can be life-threatening. In patients with intact vaginal walls and perineum, they may pose a diagnostic and therapeutic challenge. Supralevator hematomas are much less common than infralevator hematomas. We present a case of puerperal hemorrhagic shock after a normal vaginal delivery in a low-risk parous woman resulting from an occult supralevator hematoma. Because the woman was hemodynamically unstable initially, she underwent a vaginal surgical drainage. A week later, the supravaginal hematoma reformed. At this time the patient was hemodynamically stable, and ultrasound-guided drainage was performed, which resulted in complete resolution of the hematoma within 10 days. In a clinically stable puerperal patient, ultrasound-guided drainage of a supralevator hematoma resulted in rapid and complete resolution of symptoms.

  8. Efficacy of ultrasound-guided thoracentesis catheter drainage for pleural effusion

    Science.gov (United States)

    Cao, Weitian; Wang, Yi; Zhou, Ningming; Xu, Bing

    2016-01-01

    The factors influencing the efficacy of ultrasound-guided thoracentesis catheter drainage were investigated in the present study. A retrospective analysis of clinical data from 435 patients who presented with a pleural effusion was performed. Patients were divided into a control group and an intervention group. Thirty-seven patients in the control group were given standard care using pleural puncture to draw the excess fluid. The 398 patients in the intervention group were treated using ultrasound-guided thoracentesis catheter drainage. The rate of successful drainage of a pleural effusion was significantly higher (Ppleural effusion. The efficacy of the procedure is related to the separation of pleural effusion, drainage tube type and tube diameter. PMID:28105155

  9. Ultrasound guided electrochemotherapy for the treatment of a clear cell thymoma in a cat

    Directory of Open Access Journals (Sweden)

    Enrico Pierluigi Spugnini

    2017-03-01

    Full Text Available A twelve-year-old male castrated domestic shorthair cat was presented for rapidly progressing respiratory distress. The cat was depressed, tachypneic and moderately responsive. Ultrasonography showed a mediastinal mass associated with a significant pleural effusion that needed tapping every five to seven days. Ultrasound guided biopsy yielded a diagnosis of clear cell thymoma upon histopathology. After complete staging procedures, the owner elected to treat the cat with electrochemotherapy (ECT using systemic bleomycin. Two sessions of ultrasound guided ECT were performed at two week intervals with trains of biphasic electric pulses applied using needle electrodes until complete coverage of the area was achieved. The treatment was well tolerated and resulted in partial remission (PR. Additional sessions were performed on a monthly basis. The cat is still in PR after fourteen months. ECT resulted in improved local control and should be considered among the available adjuvant treatments in pets carrying visceral tumors.

  10. Novel ultrasound-responsive chitosan/perfluorohexane nanodroplets for image-guided smart delivery of an anticancer agent: Curcumin.

    Science.gov (United States)

    Baghbani, Fatemeh; Chegeni, Mahdieh; Moztarzadeh, Fathollah; Hadian-Ghazvini, Samaneh; Raz, Majid

    2017-05-01

    Ultrasound-responsive nanodroplets are a class of new emerging smart drug delivery systems which provide image-guided nano-therapy of various diseases, especially cancers. Here, we developed multifunctional smart curcumin-loaded chitosan/perfluorohexane nanodroplets for contrast-ultrasound imaging and on-demand drug delivery. The nanodroplets were synthesized via nanoemulsion process. The optimal formulation with the size of 101.2nm and 77.8% curcumin entrapment was chosen for release study and cytotoxicity evaluation. Sonication at the frequency of 1MHz, 2W/cm 2 for 4min triggered the release of 63.5% of curcumin from optimal formulation (Cur-NDs-2). Ultrasound aided release study indicated that the concentration of perfluorohexane and the degree of acoustic droplet vaporization play important role in ultrasound-active drug release. B-mode ultrasound imaging confirmed strong ultrasound contrast of chitosan nanodroplets even at low concentrations via droplet to bubble transition. Finally, cytotoxicity of the ultrasound-responsive nanodroplets in the presence of ultrasound was evaluated in-vitro on 4T1 human breast cancer cells. Cell growth inhibitory effects of curcumin-loaded nanodroplets significantly increased by ultrasound exposure. According to the obtained results, these ultrasound responsive curcumin-loaded chitosan/perfluorohexane nanodroplets have a great potential for imaged-guided cancer therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Realtime control of multiple-focus phased array heating patterns based on noninvasive ultrasound thermography.

    Science.gov (United States)

    Casper, Andrew; Liu, Dalong; Ebbini, Emad S

    2012-01-01

    A system for the realtime generation and control of multiple-focus ultrasound phased-array heating patterns is presented. The system employs a 1-MHz, 64-element array and driving electronics capable of fine spatial and temporal control of the heating pattern. The driver is integrated with a realtime 2-D temperature imaging system implemented on a commercial scanner. The coordinates of the temperature control points are defined on B-mode guidance images from the scanner, together with the temperature set points and controller parameters. The temperature at each point is controlled by an independent proportional, integral, and derivative controller that determines the focal intensity at that point. Optimal multiple-focus synthesis is applied to generate the desired heating pattern at the control points. The controller dynamically reallocates the power available among the foci from the shared power supply upon reaching the desired temperature at each control point. Furthermore, anti-windup compensation is implemented at each control point to improve the system dynamics. In vitro experiments in tissue-mimicking phantom demonstrate the robustness of the controllers for short (2-5 s) and longer multiple-focus high-intensity focused ultrasound exposures. Thermocouple measurements in the vicinity of the control points confirm the dynamics of the temperature variations obtained through noninvasive feedback. © 2011 IEEE

  12. Real-time ultrasound-guided spinal anaesthesia: a prospective observational study of a new approach.

    LENUS (Irish Health Repository)

    Conroy, P H

    2013-01-01

    Identification of the subarachnoid space has traditionally been achieved by either a blind landmark-guided approach or using prepuncture ultrasound assistance. To assess the feasibility of performing spinal anaesthesia under real-time ultrasound guidance in routine clinical practice we conducted a single center prospective observational study among patients undergoing lower limb orthopaedic surgery. A spinal needle was inserted unassisted within the ultrasound transducer imaging plane using a paramedian approach (i.e., the operator held the transducer in one hand and the spinal needle in the other). The primary outcome measure was the success rate of CSF acquisition under real-time ultrasound guidance with CSF being located in 97 out of 100 consecutive patients within median three needle passes (IQR 1-6). CSF was not acquired in three patients. Subsequent attempts combining landmark palpation and pre-puncture ultrasound scanning resulted in successful spinal anaesthesia in two of these patients with the third patient requiring general anaesthesia. Median time from spinal needle insertion until intrathecal injection completion was 1.2 minutes (IQR 0.83-4.1) demonstrating the feasibility of this technique in routine clinical practice.

  13. Novel needle guide reduces time to perform ultrasound-guided femoral nerve catheter placement: A randomised controlled trial.

    Science.gov (United States)

    Turan, Alparslan; Babazade, Rovnat; Elsharkawy, Hesham; Esa, Wael Ali Sakr; Maheshwari, Kamal; Farag, Ehab; Zimmerman, Nicole M; Soliman, Loran Mounir; Sessler, Daniel I

    2017-03-01

    Ultrasound-guided nerve blocks have become the standard when performing regional nerve blocks in anaesthesia. Infiniti Plus (CIVCO Medical Solutions, Kalona, Iowa, USA) is a needle guide that has been recently developed to help clinicians in performing ultrasound-guided nerve blocks. We tested the hypothesis that femoral nerve catheter placement carried out with the Infiniti Plus needle guide will be quicker to perform than without the Infiniti Plus. Secondary aims were to assess whether the Infiniti Plus needle guide decreased the number of block attempts and also whether it improved needle visibility. A randomised, controlled trial. Cleveland Clinic, Cleveland, Ohio, USA. We enrolled adult patients having elective total knee arthroplasty with a femoral nerve block and femoral nerve catheter. Patients, who were pregnant or those who had preexisting neuropathy involving the surgical limb, coagulopathy, infection at the block site or allergy to local anaesthetics were excluded. Patients were randomised into two groups to receive the ultrasound-guided femoral nerve catheter placement with or without the Infiniti Plus needle guide. The time taken to place the femoral nerve catheter, the number of attempts, the success rate and needle visibility were recorded. We used an overall α of 0.05 for both the primary and secondary analyses; the secondary analyses were Bonferroni corrected to control for multiple comparisons. The median (interquartile range Q1 to Q3) time to perform the femoral nerve catheter placement was 118 (100 to 150) s with Infiniti Plus and 177 (130 to 236) s without Infiniti Plus. Infiniti Plus significantly reduced the time spent performing femoral nerve catheterisation, with estimated ratio of means [(95% confidence interval), P value] of 0.67 [(0.60 to 0.75), P Infiniti Plus compared with no Infiniti Plus. However, Infiniti Plus had no effect on the odds of a successful femoral nerve catheter placement, number of attempts or percentage of perfect

  14. Design and application of model for training ultrasound-guided vascular cannulation in pediatric patients.

    Science.gov (United States)

    Pérez-Quevedo, O; López-Álvarez, J M; Limiñana-Cañal, J M; Loro-Ferrer, J F

    2016-01-01

    Central vascular cannulation is not a risk-free procedure, especially in pediatric patients. Newborn and infants are small and low-weighted, their vascular structures have high mobility because of tissue laxity and their vessels are superficial and with small diameter. These characteristics, together with the natural anatomical variability and poor collaboration of small children, make this technique more difficult to apply. Therefore, ultrasound imaging is increasingly being used to locate vessels and guide vascular access in this population. (a) To present a model that simulates the vascular system for training ultrasound-guided vascular access in pediatrics patients; (b) to ultrasound-guided vascular cannulation in the model. The model consisted of two components: (a) muscular component: avian muscle, (b) vascular component: elastic tube-like structure filled with fluid. 864 ecoguided punctures was realized in the model at different vessel depth and gauge measures were simulated, for two medical operators with different degree of experience. The average depth and diameter of vessel cannulated were 1.16 (0.42)cm and 0.43 (0.1)cm, respectively. The average number of attempts was of 1.22 (0.62). The percentage of visualization of the needle was 74%. The most frequent maneuver used for the correct location, was the modification of the angle of the needle and the relocation of the guidewire in 24% of the cases. The average time for the correct cannulations was 41 (35.8)s. The more frequent complications were the vascular perforation (11.9%) and the correct vascular puncture without possibility of introducing the guidewire (1.2%). The rate of success was 96%. The model simulates the anatomy (vascular and muscular structures) of a pediatric patient. It is cheap models, easily reproducible and a useful tool for training in ultrasound-guided puncture and cannulation. Copyright © 2015 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  15. Ultrasound-guided microwave ablation in the treatment of benign thyroid nodules in 435 patients.

    Science.gov (United States)

    Liu, Yu-Jiang; Qian, Lin-Xue; Liu, Dong; Zhao, Jun-Feng

    2017-09-01

    The objective of the present study was to investigate the effectiveness and safety of ultrasound-guided microwave ablation in the treatment of benign thyroid nodules. A total of 474 benign thyroid nodules in 435 patients who underwent ultrasound-guided microwave ablation from September 2012 to August 2015 were included. Nodule volume and thyroid function were measured before treatment and at 1, 3, 6, and 12 months and subsequently after every 6 months. The nodule volume reduction rate and changes of thyroid function were evaluated. The volume of all thyroid nodules significantly decreased after ultrasound-guided microwave ablation. The average volume was 13.07 ± 0.95 ml before treatment, and 1.14 ± 0.26 ml at 12-months follow-up. The mean volume reduction rate was 90% and the final volume reduction rate was 94%. The volume reduction rate of mainly cystic nodules was significantly higher than that of simple solid and mainly solid nodules (all P microwave ablation is an effective and safe technique for treatment of benign thyroid nodules, and has the potential for clinical applications. Impact statement Ultrasound-guided MWA is an effective and safe technique for the treatment of benign thyroid nodules. It can significantly reduce the nodule volume, improve the patients' clinical symptoms, has less complication, guarantees quick recovery, meets patients' aesthetic needs, and shows less interference on the physiological and psychological aspects of the body. MWA should be a good complement to traditional open surgery and has potentials in clinical applications.

  16. Routine ultrasound guided evacuation of first trimester missed abortion versus blind evacuation

    OpenAIRE

    Mostafa Abdulla Elsayed

    2014-01-01

    Background: The clinical management of miscarriage has changed little over the years and many women undergo surgical uterine evacuation. Surgical evacuation of the uterine contents in missed abortion is a challenge to the obstetrician as it is done blindly. The current study recommends the use of ultrasound guided surgical evacuation. It serves two important advantages; the first is to complete evacuation without the need of additional step. The second is to protect against uterine perforatio...

  17. Safety of Ultrasound-Guided Botulinum Toxin Injections for Sialorrhea as Performed by Pediatric Otolaryngologists.

    Science.gov (United States)

    Shariat-Madar, Bahbak; Chun, Robert H; Sulman, Cecille G; Conley, Stephen F

    2016-05-01

    To evaluate incidence of complications and hospital readmission as a result of ultrasound-guided botulinum toxin injections to manage sialorrhea. Case series with chart review. Children's Hospital of Wisconsin. A case series with chart review was performed of all cases of ultrasound-guided injection of botulinum toxin by pediatric otolaryngologists from March 5, 2010, to September 26, 2014,. Primary outcomes included complications such as dysphagia, aspiration pneumonia, and motor paralysis. Secondary outcomes included hospitalization, intubation, and nasogastric tube placement. There were 48 patients, 111 interventions, and 306 intraglandular injections identified. Botulinum toxin type A and type B were utilized in 4 and 107 operative interventions, respectively. Type A was injected into 4 parotid and 4 submandibular glands, utilizing doses of 20 U per parotid and 30 U per submandibular gland. Type B was injected into 98 parotid and 200 submandibular glands, with average dosing of 923 U per parotid and 1170 U per submandibular gland, respectively. There were 2 instances of subjectively worsening of baseline dysphagia that self-resolved. No cases were complicated by aspiration pneumonia or motor paralysis. No patients required hospital readmission, intubation, or nasogastric tube placement. Prior published data indicated 16% complication incidence with ultrasound-guided injection of botulinum toxin. Our study found a low complication rate (0.6%) with ultrasound-guided injections of botulinum toxin to manage sialorrhea, without cases of aspiration pneumonia or motor paralysis. Of 306 intraglandular injections, there were 2 cases of worsening baseline subjective dysphagia that self-resolved. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  18. Ultrasound-guided interstitial laser photocoagulation of an autonomous thyroid nodule

    DEFF Research Database (Denmark)

    Døssing, Helle; Bennedbaek, Finn Noe; Hegedüs, Laszlo

    2003-01-01

    effects and often necessitates multiple treatment sessions. We present a case of a 17-year-old female successfully treated with ultrasound (US)-guided percutaneous interstitial laser photocoagulation (ILP) for an AFTN. Initially, she had a serum thyrotropin (TSH) of 0.01 mU/L and normal peripheral thyroid.......9 mL (40% reduction) without further alterations during an additional 9 months of follow-up. Side effects were transient thyrotoxicosis and local pain as seen with PEI. To our knowledge, this is the first reported case of ILP used in a patient with a pretoxic thyroid nodule. US-guided thermic tissue...

  19. Palpation- and ultrasound-guided brachial plexus blockade in Hispaniolan Amazon parrots (Amazona ventralis).

    Science.gov (United States)

    da Cunha, Anderson F; Strain, George M; Rademacher, Nathalie; Schnellbacher, Rodney; Tully, Thomas N

    2013-01-01

    To compare palpation-guided with ultrasound-guided brachial plexus blockade in Hispaniolan Amazon parrots. Prospective randomized experimental trial. Eighteen adult Hispaniolan Amazon parrots (Amazona ventralis) weighing 252-295 g. After induction of anesthesia with isoflurane, parrots received an injection of lidocaine (2 mg kg(-1)) in a total volume of 0.3 mL at the axillary region. The birds were randomly assigned to equal groups using either palpation or ultrasound as a guide for the brachial plexus block. Nerve evoked muscle potentials (NEMP) were used to monitor effectiveness of brachial plexus block. The palpation-guided group received the local anesthetic at the space between the pectoral muscle, triceps, and supracoracoideus aticimus muscle, at the insertion of the tendons of the caudal coracobrachial muscle, and the caudal scapulohumeral muscle. For the ultrasound-guided group, the brachial plexus and the adjacent vessels were located with B-mode ultrasonography using a 7-15 MHz linear probe. After location, an 8-5 MHz convex transducer was used to guide injections. General anesthesia was discontinued 20 minutes after lidocaine injection and the birds recovered in a padded cage. Both techniques decreased the amplitude of NEMP. Statistically significant differences in NEMP amplitudes, were observed within the ultrasound-guided group at 5, 10, 15, and 20 minutes after injection and within the palpation-guided group at 10, 15, and 20 minutes after injection. There was no statistically significant difference between the two groups. No effect on motor function, muscle relaxation or wing droop was observed after brachial plexus block. The onset of the brachial plexus block tended to be faster when ultrasonography was used. Brachial plexus injection can be performed in Hispaniolan Amazon parrots and nerve evoked muscle potentials were useful to monitor the effects on nerve conduction in this avian species. Neither technique produced an effective block at the

  20. Ultrasound-guided percutaneous transhepatic biliary drainage: Experiences in 146 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jai Keun [Sohwa Children' s Hospital, Seoul(Korea, Republic of); Yu, Jeong Sik; Kim, Ki Whang; Chung, Soo Yoon; Jeong, Mi Gyoung [Yonsei University College of Medicine, Seoul (Korea, Republic of); Choi, Deuk Lin; Kwon, Gui Hyang; Lee, Hae Kyung [Soonchunhyang University College of Medicine, Seoul (Korea, Republic of)

    1999-03-15

    Percutaneous biliary drainage is an important technique for palliative therapy of obstructive biliary disease and diagnostic information. The purpose of this study is to review and evaluate the experiences of ultrasound-guided percutaneous transhepatic biliary drainage. Ultrasound-guided percutaneous transhepatic biliary drainage was performed on 146 occasions in 134 patients. The causes of biliary obstruction were: benign diseases (19 cases, 14.2%) such as bile duct stones or stricture, cholangiocarcinoma (37 cases, 27.6%), pancreatic carcinoma (35 cases, 26.1%), metastasis (22 cases, 16.5%), gall bladder cancer (14 cases, 10.4%), ampulla of Vater cancer (4 cases, 3.0%), hepatocellular carcinoma (3 cases, 2.2%). Retrospectively reviewing medical records, we found out frequency of external or external/internal biliary drainages, puncture of left or right hepatic duct, and presence of bileinfection. Ultrasound-guided percutaneous transhepatic biliary drainage was compared with conventional biliary drainage of previous reports on the basis of frequency of complications. External (124 procedures, 84.9%) and external/internal biliary drainage (22 procedures, 15.1%) were carried out by puncture of dilated right (59.6%) or left (40.4%) intrahepatic duct. Sixty-nine complications occurred in 47 patients. Catheter related complications (33/69, 47.8%) were most common: catheter dislodgement (17/69, 24.6%), malfunction (9/69, 13.1%), leakage (7/69, 10.1%). Other minor complications such as simple fever (16/69, 23.2%), cholangitis (7/69, 10.1%), hemobilia (4/69, 5.8%), biloma (2/69, 2.9%) and wound infection (1/69, 1.5%) occurred. Major complications including sepsis (4/69, 5.8%) and bile peritonitis (2/69, 2.9%) were also noted. Puncture-related complications such as hemobilia, biloma and bile peritonitis occurred in 8 cases (5.5%). Comparing with conventional X-ray guided drainage, ultrasound-guided percutaneous transhepatic biliary drainage is a safe procedure for

  1. Ultrasound guided needle biopsy of skeletal muscle in neuromuscular disease

    DEFF Research Database (Denmark)

    Lindequist, S; Schrøder, H D; Larsen, C

    1990-01-01

    Guided by ultrasonography percutaneous needle biopsy of skeletal muscle was performed in 24 patients, using the one hand held Biopty system and a 2 mm Tru-Cut needle. The specimens were graded with regard to diagnostic quality and utility and almost all specimens (96%) were of highest quality. Th....... The use of ultrasonography was helpful in selecting a suitable area for the biopsy and vascular structures could be avoided. The procedure was well tolerated and easy to perform, and no complications were recorded....

  2. Using passive cavitation images to classify high-intensity focused ultrasound lesions.

    Science.gov (United States)

    Haworth, Kevin J; Salgaonkar, Vasant A; Corregan, Nicholas M; Holland, Christy K; Mast, T Douglas

    2015-09-01

    Passive cavitation imaging provides spatially resolved monitoring of cavitation emissions. However, the diffraction limit of a linear imaging array results in relatively poor range resolution. Poor range resolution has limited prior analyses of the spatial specificity and sensitivity of passive cavitation imaging in predicting thermal lesion formation. In this study, this limitation is overcome by orienting a linear array orthogonal to the high-intensity focused ultrasound propagation direction and performing passive imaging. Fourteen lesions were formed in ex vivo bovine liver samples as a result of 1.1-MHz continuous-wave ultrasound exposure. The lesions were classified as focal, "tadpole" or pre-focal based on their shape and location. Passive cavitation images were beamformed from emissions at the fundamental, harmonic, ultraharmonic and inharmonic frequencies with an established algorithm. Using the area under a receiver operating characteristic curve (AUROC), fundamental, harmonic and ultraharmonic emissions were found to be significant predictors of lesion formation for all lesion types. For both harmonic and ultraharmonic emissions, pre-focal lesions were classified most successfully (AUROC values of 0.87 and 0.88, respectively), followed by tadpole lesions (AUROC values of 0.77 and 0.64, respectively) and focal lesions (AUROC values of 0.65 and 0.60, respectively). Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  3. Comparison of two ultrasound-guided injection techniques targeting the sacroiliac joint region in equine cadavers.

    Science.gov (United States)

    Stack, John David; Bergamino, Chiara; Sanders, Ruth; Fogarty, Ursula; Puggioni, Antonella; Kearney, Clodagh; David, Florent

    2016-09-20

    To compare the accuracy and distribution of injectate for cranial (CR) and caudomedial (CM) ultrasound-guided injections of equine sacroiliac joints. Both sacroiliac joints from 10 lumbosacropelvic specimens were injected using cranial parasagittal (CR; curved 18 gauge, 25 cm spinal needles) and caudomedial (CM; straight 18 gauge, 15 cm spinal needles) ultrasound-guided approaches. Injectate consisted of 4 ml iodinated contrast and 2 ml methylene blue. Computed tomographical (CT) scans were performed before and after injections. Time for needle guidance and repositioning attempts were recorded. The CT sequences were analysed for accuracy and distribution of contrast. Intra-articular contrast was detected in sacroiliac joints following 15/40 injections. The CR and CM approaches deposited injectate ≤2 cm from sacroiliac joint margins following 17/20 and 20/20 injections, respectively. Median distance of closest contrast to the sacroiliac joint was 0.4 cm (interquartile range [IQR]: 1.5 cm) for CR approaches and 0.6 cm (IQR: 0.95 cm) for CM approaches. Cranial injections resulted in injectate contacting lumbosacral intertransverse joints 15/20 times. Caudomedial injections were perivascular 16/20 times. Safety and efficacy could not be established. Cranial and CM ultrasound-guided injections targeting sacroiliac joints were very accurate for periarticular injection, but accuracy was poor for intra-articular injection. Injectate was frequently found in contact with interosseous sacroiliac ligaments, as well as neurovascular and synovial structures in close vicinity of sacroiliac joints.

  4. Ultrasound-guided percutaneous drainage of meniscal cysts: preliminary clinical experience

    International Nuclear Information System (INIS)

    MacMahon, P.J.; Brennan, D.D.; Duke, D.; Forde, S.; Eustace, S.J.

    2007-01-01

    Aim: To evaluate the efficacy of ultrasound-guided percutaneous drainage of symptomatic meniscal cysts. Materials and methods: Patients with lateral knee joint tenderness and swelling and confirmed meniscal cyst on magnetic resonance imaging (MRI) were consecutively enrolled for ultrasound-guided percutaneous cyst aspiration. Cysts were injected with local anaesthetic and steroid before completion of procedure. All 18 patients (all male, average age 33 years) were subsequently followed up (average time 10 months) and meniscal cyst symptoms assessed by questionnaire. Fischer's exact test used to analyse the data. Results: In every case the procedure was well tolerated, and each patient indicated that they would be willing to have a repeat procedure in the future. Ten patients reported complete resolution of symptoms secondary to therapeutic cyst aspiration and had resumed participation in high-performance sport. Two patients reported a satisfactory sustained response, reporting only occasional 'twinges of pain'. In the remaining six patients, symptoms returned after an initial pain-free period. The pain-free period ranged from 1-8 weeks. In this study, patient outcome did not significantly correlate with any meniscal cyst characteristic. Conclusion: Ultrasound-guided percutaneous aspiration of meniscal cysts is a well-tolerated, simple, and safe procedure. In this small patient series, it was associated with positive early results with favourable outcomes in the mid to long-term. It should be considered in patients unsuitable for surgical debridement or as an interim therapy if surgery is delayed or postponed

  5. In-Plane Ultrasound-Guided Knee Injection Through a Lateral Suprapatellar Approach: A Safe Technique.

    Science.gov (United States)

    Chagas-Neto, Francisco A; Taneja, Atul K; Gregio-Junior, Everaldo; Nogueira-Barbosa, Marcello H

    2017-06-01

    This study aims to describe a technique for in-plane ultrasound-guided knee arthrography through a lateral suprapatellar approach, reporting its accuracy and related complications. A retrospective search was performed for computed tomography and magnetic resonance reports from June 2013 through June 2015. Imaging studies, puncture descriptions, and guided-procedure images were reviewed along with clinical and surgical history. A fellowship-trained musculoskeletal radiologist performed all procedures under sterile technique and ultrasound guidance with the probe in oblique position on the lateral suprapatellar recess after local anesthesia with the patient on dorsal decubitus, hip in neutral rotation, and 30 to 45 degrees of knee flexion. A total of 86 consecutive subjects were evaluated (mean, 55 years). All subjects underwent intra-articular injection of contrast, which was successfully reached in the first attempt in 94.2% of the procedures (81/86), and in the second attempt in 5.8% (5/86) after needle repositioning without a second puncture. There were no postprocedural reports of regional complications at the puncture site, such as significant pain, bleeding, or vascular lesions. Our study demonstrates that in-plane ultrasound-guided injection of the knee in semiflexion approaching the lateral suprapatellar recess is a safe and useful technique to administer intra-articular contrast solution, as an alternative method without radiation exposure.

  6. Outcome of ultrasound-guided small-bore catheter drainage in exudative pleural effusions.

    Science.gov (United States)

    Kiranantawat, Nantaka; Sungsiri, Jitpreedee; Geater, Sarayut L

    2014-05-01

    To evaluate the outcome and safety of ultrasound-guided percutaneous catheter drainage of exudative pleural effusion. The present study was a retrospective analysis of 412 pleural effusions from 373 patients that underwent ultrasound-guided small-bore catheter drainage in exudative pleural effusions between 2004 and 2009. The two most common causes for drainage were parapneumonic effusion or empyema (52.2%) and malignant effusion (30.3%), while the remains were trauma, iatrogenic, and others. Overall clinical success rate was 76.5%. The success rate was lower among malignant pleural effusion (p = 0.003). Causes of effusion were the only independent predictors related to success. Only five (1.2%) patients developed complication during the procedure. Seventy-five of 412 effusions (15.8%) developed complication during the period of drainage; the majority were drain blockage (9%) and accidental dislodgment (4.1%). Ultrasound-guided small-bore catheter drainage was a safe and efficient procedure for exudative pleural effusions.

  7. Diagnostic efficacy of ultrasound-guided core-needle biopsy of peripheral lymph nodes in sarcoidosis.

    Science.gov (United States)

    Boussouar, S; Medjhoul, A; Bernaudin, J F; Tayebjee, O; Soussan, M; Uzunhan, Y; Nunes, H; Kambouchner, M; Martin, A; Valeyre, D; Brillet, P Y

    2015-09-14

    Core-needle biopsy guided by ultrasound can be performed for investigating peripheral lymph node (PLN). The aim of this study was to determine the efficacy of this technique in sarcoidosis. Retrospective review of files of all patients in the database of the radiology department of Avicenne university hospital who underwent PLN biopsies guided by ultrasound from January 2008 to June 2011 (n=292). Cases with either granulomas at histology with the procedure or with a final diagnosis of sarcoidosis were included in the study. The histological specimens were adequate in 282 out of 292 cases (96%) showing non-caseating granulomas in 22 cases (n=20 patients with a final diagnosis of sarcoidosis and n=2 patients with tuberculosis). After reviewing clinical files of the 282 patient, 22 were confirmed to have sarcoidosis, at initial presentation (n=19) or later during flare-up or relapse (n=3) with only 2 patients having no granuloma on PLN biopsy. PLN were palpable in 18 cases and only detected by (18F)FDG-PET/CT showing increased PLN uptake in 4 cases. The sensitivity and specificity of adequate biopsy were 91 and 99% and the positive and negative predictive values were 91 and 99%, respectively. Core-needle biopsy guided by ultrasound has a high efficacy for evidencing granulomas in sarcoidosis patients with PLN involvement either clinically palpable or in the presence of (18F)FDG-PET/CT uptake.

  8. Ultrasound guided electrical impedance tomography for 2D free-interface reconstruction

    Science.gov (United States)

    Liang, Guanghui; Ren, Shangjie; Dong, Feng

    2017-07-01

    The free-interface detection problem is normally seen in industrial or biological processes. Electrical impedance tomography (EIT) is a non-invasive technique with advantages of high-speed and low cost, and is a promising solution for free-interface detection problems. However, due to the ill-posed and nonlinear characteristics, the spatial resolution of EIT is low. To deal with the issue, an ultrasound guided EIT is proposed to directly reconstruct the geometric configuration of the target free-interface. In the method, the position of the central point of the target interface is measured by a pair of ultrasound transducers mounted at the opposite side of the objective domain, and then the position measurement is used as the prior information for guiding the EIT-based free-interface reconstruction. During the process, a constrained least squares framework is used to fuse the information from different measurement modalities, and the Lagrange multiplier-based Levenberg-Marquardt method is adopted to provide the iterative solution of the constraint optimization problem. The numerical results show that the proposed ultrasound guided EIT method for the free-interface reconstruction is more accurate than the single modality method, especially when the number of valid electrodes is limited.

  9. Ultrasound guided electrical impedance tomography for 2D free-interface reconstruction

    International Nuclear Information System (INIS)

    Liang, Guanghui; Ren, Shangjie; Dong, Feng

    2017-01-01

    The free-interface detection problem is normally seen in industrial or biological processes. Electrical impedance tomography (EIT) is a non-invasive technique with advantages of high-speed and low cost, and is a promising solution for free-interface detection problems. However, due to the ill-posed and nonlinear characteristics, the spatial resolution of EIT is low. To deal with the issue, an ultrasound guided EIT is proposed to directly reconstruct the geometric configuration of the target free-interface. In the method, the position of the central point of the target interface is measured by a pair of ultrasound transducers mounted at the opposite side of the objective domain, and then the position measurement is used as the prior information for guiding the EIT-based free-interface reconstruction. During the process, a constrained least squares framework is used to fuse the information from different measurement modalities, and the Lagrange multiplier-based Levenberg–Marquardt method is adopted to provide the iterative solution of the constraint optimization problem. The numerical results show that the proposed ultrasound guided EIT method for the free-interface reconstruction is more accurate than the single modality method, especially when the number of valid electrodes is limited. (paper)

  10. Neuroprotective effects of ultrasound-guided nerve growth factor injections after sciatic nerve injury

    Directory of Open Access Journals (Sweden)

    Hong-fei Li

    2015-01-01

    Full Text Available Nerve growth factor (NGF plays an important role in promoting neuroregeneration after peripheral nerve injury. However, its effects are limited by its short half-life; it is therefore important to identify an effective mode of administration. High-frequency ultrasound (HFU is increasingly used in the clinic for high-resolution visualization of tissues, and has been proposed as a method for identifying and evaluating peripheral nerve damage after injury. In addition, HFU is widely used for guiding needle placement when administering drugs to a specific site. We hypothesized that HFU guiding would optimize the neuroprotective effects of NGF on sciatic nerve injury in the rabbit. We performed behavioral, ultrasound, electrophysiological, histological, and immunohistochemical evaluation of HFU-guided NGF injections administered immediately after injury, or 14 days later, and compared this mode of administration with intramuscular NGF injections. Across all assessments, HFU-guided NGF injections gave consistently better outcomes than intramuscular NGF injections administered immediately or 14 days after injury, with immediate treatment also yielding better structural and functional results than when the treatment was delayed by 14 days. Our findings indicate that NGF should be administered as early as possible after peripheral nerve injury, and highlight the striking neuroprotective effects of HFU-guided NGF injections on peripheral nerve injury compared with intramuscular administration.

  11. Ultrasound guided percutaneous removal of wooden foreign bodies in the extremities with hydro-dissection technique

    Energy Technology Data Exchange (ETDEWEB)

    Park, HeeJin; Lee, So Yeon; Chung, Eun Chul; Rho, Myung Ho [Dept. of Radiology, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, Seoul (Korea, Republic of); Lee, Sung Moon; Son, Eun Seok [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of); Lee, Sun Joo [Dept. of Radiology, Inje University College of Medicine, Busan Paik Hospital, Busan (Korea, Republic of)

    2015-12-15

    We described the technique of ultrasound (US)-guided percutaneous removal of the foreign bodies (FB) with hydro-dissection in the radiologic department and presented video files of several cases.Four patients referred to the radiology department for US evaluation and US-guided percutaneous removal of the FBs in the upper and lower extremities between November, 2006 and November, 2013 were included in this study. The procedures started with US evaluation for the exact location and shape of the FB. A 5 mm-sized skin incision was made at the site of the nearest point from the FB where no passing arteries or tendons were present. We adopted a hydro dissection technique to separate the FB from adjacent tissue using a 2% lidocaine solution. Injected anesthetics detached the FBs from surrounding tissue and thereby facilitated removal. After the tip of the mosquito forceps reached the FB, the wooden FBs were removed. The mean time required for the entire procedure was approximately 20 minutes. There were no significant complications during the US-guided removal or long-term complications after the procedure. All 4 FBs were successfully removed from the soft tissue under US guidance. Ultrasound-guided percutaneous removal of the FBs with hydro-dissection in the radiology department is a less invasive and safe method over surgical removal in the operating room. Additionally, the use of a guide wire and serial dilator may help minimize soft tissue injury and facilitate the introduction of forceps.

  12. Thrombolysis using multi-frequency high intensity focused ultrasound at MHz range: an in vitro study

    International Nuclear Information System (INIS)

    Suo, Dingjie; Guo, Sijia; Jiang, Xiaoning; Jing, Yun; Lin, Weili

    2015-01-01

    High intensity focused ultrasound (HIFU) based thrombolysis has emerged as a promising drug-free treatment approach for ischemic stroke. The large amount of acoustic power required by this approach, however, poses a critical challenge to the future clinical translation. In this study, multi-frequency acoustic waves at MHz range (near 1.5 MHz) were introduced as HIFU excitations to reduce the required power for treatment as well as the treatment time. In vitro bovine blood clots weighing around 150 mg were treated by single-frequency and multi-frequency HIFU. The pulse length was 2 ms for all experiments except the ones where the duty cycle was changed. It was found that dual-frequency thrombolysis efficiency was statistically better than single-frequency under the same acoustic power and excitation condition. When varying the acoustic power but fixing the duty cycle at 5%, it was found that dual-frequency ultrasound can save almost 30% power in order to achieve the same thrombolysis efficiency. In the experiment where the duty cycle was increased from 0.5% to 10%, it was shown that dual-frequency ultrasound can achieve the same thrombolysis efficiency with only half of the duty cycle of single-frequency. Dual-frequency ultrasound could also accelerate the thrombolysis by a factor of 2–4 as demonstrated in this study. No significant differences were found between dual-frequencies with different frequency differences (0.025, 0.05, and 0.1 MHz) and between dual-frequency and triple-frequency. The measured cavitation doses of dual-frequency and triple-frequency excitations were at about the same level but both were significantly higher than that of single-frequency. (paper)

  13. Multi-parametric monitoring and assessment of high-intensity focused ultrasound (HIFU) boiling by harmonic motion imaging for focused ultrasound (HMIFU): an ex vivo feasibility study

    International Nuclear Information System (INIS)

    Hou, Gary Y; Marquet, Fabrice; Wang, Shutao; Konofagou, Elisa E

    2014-01-01

    Harmonic motion imaging for focused ultrasound (HMIFU) is a recently developed high-intensity focused ultrasound (HIFU) treatment monitoring method with feasibilities demonstrated in vitro and in vivo. Here, a multi-parametric study is performed to investigate both elastic and acoustics-independent viscoelastic tissue changes using the Harmonic Motion Imaging (HMI) displacement, axial compressive strain and change in relative phase shift during high energy HIFU treatment with tissue boiling. Forty three (n = 43) thermal lesions were formed in ex vivo canine liver specimens (n = 28). Two-dimensional (2D) transverse HMI displacement maps were also obtained before and after lesion formation. The same method was repeated in 10 s, 20 s and 30 s HIFU durations at three different acoustic powers of 8, 10, and 11 W, which were selected and verified as treatment parameters capable of inducing boiling using both thermocouple and passive cavitation detection (PCD) measurements. Although a steady decrease in the displacement, compressive strain, and relative change in the focal phase shift (Δϕ) were obtained in numerous cases, indicating an overall increase in relative stiffness, the study outcomes also showed that during boiling, a reverse lesion-to-background displacement contrast was detected, indicating potential change in tissue absorption, geometrical change and/or, mechanical gelatification or pulverization. Following treatment, corresponding 2D HMI displacement images of the thermal lesions also mapped consistent discrepancy in the lesion-to-background displacement contrast. Despite the expectedly chaotic changes in acoustic properties with boiling, the relative change in phase shift showed a consistent decrease, indicating its robustness to monitor biomechanical properties independent of the acoustic property changes throughout the HIFU treatment. In addition, the 2D HMI displacement images confirmed and indicated the increase in the thermal lesion size with

  14. Functional Assay of Cancer Cell Invasion Potential Based on Mechanotransduction of Focused Ultrasound

    Directory of Open Access Journals (Sweden)

    Andrew C. Weitz

    2017-08-01

    Full Text Available Cancer cells undergo a number of biophysical changes as they transform from an indolent to an aggressive state. These changes, which include altered mechanical and electrical properties, can reveal important diagnostic information about disease status. Here, we introduce a high-throughput, functional technique for assessing cancer cell invasion potential, which works by probing for the mechanically excitable phenotype exhibited by invasive cancer cells. Cells are labeled with fluorescent calcium dye and imaged during stimulation with low-intensity focused ultrasound, a non-contact mechanical stimulus. We show that cells located at the focus of the stimulus exhibit calcium elevation for invasive prostate (PC-3 and DU-145 and bladder (T24/83 cancer cell lines, but not for non-invasive cell lines (BPH-1, PNT1A, and RT112/84. In invasive cells, ultrasound stimulation initiates a calcium wave that propagates from the cells at the transducer focus to other cells, over distances greater than 1 mm. We demonstrate that this wave is mediated by extracellular signaling molecules and can be abolished through inhibition of transient receptor potential channels and inositol trisphosphate receptors, implicating these proteins in the mechanotransduction process. If validated clinically, our technology could provide a means to assess tumor invasion potential in cytology specimens, which is not currently possible. It may therefore have applications in diseases such as bladder cancer, where cytologic diagnosis of tumor invasion could improve clinical decision-making.

  15. An ex vivo feasibility experimental study on targeted cell surgery by high intensity focused ultrasound

    Science.gov (United States)

    Wang, Zhi Biao; Wu, Junru; Fang, Liao Qiong; Wang, Hua; Li, Fa Qi; Tian, Yun Bo; Gong, Xiao Bo; Zhang, Hong; Zhang, Lian; Feng, Ruo

    2012-10-01

    High intensity focused ultrasound (HIFU) has become a new noninvasive surgical modality in medicine. A portion of tissue seated inside a patient's body may experience coagulative necrosis after a few seconds of insonification by high intensity focused ultrasound (US) generated by an extracorporeal focusing US transducer. The region of tissue affected by coagulative necrosis (CN) usually has an ellipsoidal shape when the thermal effect due to US absorption plays the dominant role. Its long and short axes are parallel and perpendicular to the US propagation direction respectively. It was shown by ex vivo experiments that the dimension of the short and long axes of the tissue which experiences CN can be as small as 50 μm and 250 μm respectively after one second exposure of US pulse (the spatial and pulse average acoustic power is on the order of tens of Watts and the local acoustic spatial and temporal pulse averaged intensity is on the order of 3 × 104 W/cm2) generated by a 1.6 MHz HIFU transducer of 12 cm diameter and 11 cm geometric focal length (f-number = 0.92). The numbers of cells which suffered CN were estimated to be on the order of 40. This result suggests that HIFU is able to interact with tens of cells at/near its focal zone while keeping the neighboring cells minimally affected, and thus the targeted cell surgery may be achievable.

  16. Determination of optimal ultrasound planes for the initialisation of image registration during endoscopic ultrasound-guided procedures.

    Science.gov (United States)

    Bonmati, Ester; Hu, Yipeng; Gibson, Eli; Uribarri, Laura; Keane, Geri; Gurusami, Kurinchi; Davidson, Brian; Pereira, Stephen P; Clarkson, Matthew J; Barratt, Dean C

    2018-06-01

    Navigation of endoscopic ultrasound (EUS)-guided procedures of the upper gastrointestinal (GI) system can be technically challenging due to the small fields-of-view of ultrasound and optical devices, as well as the anatomical variability and limited number of orienting landmarks during navigation. Co-registration of an EUS device and a pre-procedure 3D image can enhance the ability to navigate. However, the fidelity of this contextual information depends on the accuracy of registration. The purpose of this study was to develop and test the feasibility of a simulation-based planning method for pre-selecting patient-specific EUS-visible anatomical landmark locations to maximise the accuracy and robustness of a feature-based multimodality registration method. A registration approach was adopted in which landmarks are registered to anatomical structures segmented from the pre-procedure volume. The predicted target registration errors (TREs) of EUS-CT registration were estimated using simulated visible anatomical landmarks and a Monte Carlo simulation of landmark localisation error. The optimal planes were selected based on the 90th percentile of TREs, which provide a robust and more accurate EUS-CT registration initialisation. The method was evaluated by comparing the accuracy and robustness of registrations initialised using optimised planes versus non-optimised planes using manually segmented CT images and simulated ([Formula: see text]) or retrospective clinical ([Formula: see text]) EUS landmarks. The results show a lower 90th percentile TRE when registration is initialised using the optimised planes compared with a non-optimised initialisation approach (p value [Formula: see text]). The proposed simulation-based method to find optimised EUS planes and landmarks for EUS-guided procedures may have the potential to improve registration accuracy. Further work will investigate applying the technique in a clinical setting.

  17. Ultrasound-guided facet block to low back pain: a case report

    Directory of Open Access Journals (Sweden)

    Ana Ellen Q. Santiago

    2014-07-01

    Full Text Available BACKGROUND: Osteoarthrosis is a common cause of low back pain. The diagnosis is clinical and can be confirmed by imaging studies. Pain treatment and confirmation of diagnosis are made by intra-articular injection of corticosteroid and by local anesthetic use, due to clinical improvement. A direct monitoring of the procedure can be done under fluoroscopy, a classic technique, or else by an ultrasound-guided procedure. CASE REPORT: Female patient, 88 years old, 1.68 m and 72 kg, with facet osteoarthrosis at L2-L3, L3-L4 and L4-L5 for two years. On physical examination, she exhibited pain on lateralization and spinal extension. We opted in favor of an ultrasound-guided facet joint block. A midline spinal longitudinal scan was obtained, with identification of the desired joint space at L3-L4. A 25 G needle was inserted into the skin by the echographic off-plane ultrasound technique. 1 mL of contrast was administered, with confirmation by fluoroscopy. After aspiration of the contrast, 1 mL of solution containing 0.25% bupivacaine hydrochloride and 10 mg of methylprednisolone acetate was injected. Injections into L3-L4, L2-L3 and L1-L2 to the right were applied. CONCLUSIONS: The visualization of the facet joint by ultrasound involves minimal risk, besides reduction of radiation. This option is suitable for a large part of the population. However, fluoroscopy and computed tomography remain as monitoring techniques indicated for patients with specific characteristics, such as obesity, severe degenerative diseases and anatomical malformations, in which the ultrasound technique is still in need of further study.

  18. Ultrasound-guided pigtail catheters for drainage of various pleural diseases.

    Science.gov (United States)

    Liu, Yi-Heng; Lin, Yu-Chao; Liang, Shinn-Jye; Tu, Chih-Yen; Chen, Chia-Hung; Chen, Hung-Jen; Chen, Wei; Shih, Chuen-Ming; Hsu, Wu-Huei

    2010-10-01

    Little is known about the efficacy and safety of ultrasound-guided pigtail catheters for the management of various pleural diseases in the emergency department, ward, and intensive care unit. We conducted a retrospective study in a university hospital during a 1-year interval. A total of 276 patients (178 men and 98 women) underwent 332 pigtail catheters (the drain size ranged from 10F to 16F) under ultrasound guidance. The mean ± SEM patient age was 59 ± 18 years, and mean duration of drainage was 6.1 ± 2 days. A total of 64 drains (19.2%) were inserted for pneumothoraces; 98 drains (29.5%), for malignant effusions; 119 drains (35.8%), for parapneumonic effusions/empyemas; and 38 drains (11.4%), for massive transudate pleural effusions. The overall success rate was 72.9%. The success rate was highest when the drain was used to treat massive transudate effusions (81.6%) and malignant pleural effusions (75.5%), followed by parapneumonic effusions/empyemas (72.2%), hemothoraces (66.6%), and pneumothoraces (64.0%). Only 10 (3.0%) drains had complications due to the procedure, including infection (n = 4, 1.2%), dislodgment (n = 4, 1.2%), wound bleeding at the pigtail catheter puncture area complicated with hemothoraces (n = 1, 0.3%), and lung puncture (n = 1, 0.3%). There was no significant difference in success rate when different catheter sizes were used to treat pleural diseases. Ultrasound-guided pigtail catheters provide a safe and effective method of draining various pleural diseases. We strongly suggest that ultrasound-guided pigtail catheters be considered as the initial draining method for a variety of pleural diseases. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Focused ultrasound transducer spatial peak intensity estimation: a comparison of methods

    Science.gov (United States)

    Civale, John; Rivens, Ian; Shaw, Adam; ter Haar, Gail

    2018-03-01

    Characterisation of the spatial peak intensity at the focus of high intensity focused ultrasound transducers is difficult because of the risk of damage to hydrophone sensors at the high focal pressures generated. Hill et al (1994 Ultrasound Med. Biol. 20 259-69) provided a simple equation for estimating spatial-peak intensity for solid spherical bowl transducers using measured acoustic power and focal beamwidth. This paper demonstrates theoretically and experimentally that this expression is only strictly valid for spherical bowl transducers without a central (imaging) aperture. A hole in the centre of the transducer results in over-estimation of the peak intensity. Improved strategies for determining focal peak intensity from a measurement of total acoustic power are proposed. Four methods are compared: (i) a solid spherical bowl approximation (after Hill et al 1994 Ultrasound Med. Biol. 20 259-69), (ii) a numerical method derived from theory, (iii) a method using measured sidelobe to focal peak pressure ratio, and (iv) a method for measuring the focal power fraction (FPF) experimentally. Spatial-peak intensities were estimated for 8 transducers at three drive powers levels: low (approximately 1 W), moderate (~10 W) and high (20-70 W). The calculated intensities were compared with those derived from focal peak pressure measurements made using a calibrated hydrophone. The FPF measurement method was found to provide focal peak intensity estimates that agreed most closely (within 15%) with the hydrophone measurements, followed by the pressure ratio method (within 20%). The numerical method was found to consistently over-estimate focal peak intensity (+40% on average), however, for transducers with a central hole it was more accurate than using the solid bowl assumption (+70% over-estimation). In conclusion, the ability to make use of an automated beam plotting system, and a hydrophone with good spatial resolution, greatly facilitates characterisation of the FPF, and

  20. Lean Six Sigma Applied to Ultrasound Guided Needle Biopsy in the Head and Neck.

    Science.gov (United States)

    Matt, Bruce H; Woodward-Hagg, Heather K; Wade, Christopher L; Butler, Penny D; Kokoska, Mimi S

    2014-07-01

    (1) Confirm the positive value stream of office-based ultrasound using Lean Six Sigma; (2) demonstrate how ultrasound reduces time to diagnosis, costs, patient inconvenience and travel, exposure to ionizing radiation, intravenous contrast, and laboratory tests. Case series with historical controls using chart review. Tertiary Veterans Administration Hospital (university-affiliated). Patients with a consult request or decision for ultrasound guided fine needle aspiration (USFNA) from 2006 to 2012. Process evaluation using Lean Six Sigma methodologies; years study conducted: 2006-2012; outcome measurements: type of diagnostic tests and imaging studies including CT scans with associated radiation exposure, time to preliminary and final cytopathologic diagnosis, episodes of patient travel. Value stream mapping prior to and after implementing office-based ultrasound confirmed the time from consult request or decision for USFNA to completion of the USFNA was reduced from a range of 0 to 286 days requiring a maximum 17 steps to a range of 0 to 48 days, necessitating only a maximum of 9 steps. Office-based USFNA for evaluation of head and neck lesions reduced costs, time to diagnosis, risks and inconvenience to patients, radiation exposure, unnecessary laboratory, and patient complaints while increasing staff satisfaction. In addition, office-based ultrasound also changed the clinical management of specific patients. Lean Six Sigma reduces waste and optimizes quality and accuracy in manufacturing. This is the first known application of Lean Six Sigma to office-based USFNA in the evaluation of head and neck lesions. The literature supports the value of office-based ultrasound to patients and health care systems. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  1. Preliminary study of ergonomic behavior during simulated ultrasound-guided regional anesthesia using a head-mounted display.

    Science.gov (United States)

    Udani, Ankeet D; Harrison, T Kyle; Howard, Steven K; Kim, T Edward; Brock-Utne, John G; Gaba, David M; Mariano, Edward R

    2012-08-01

    A head-mounted display provides continuous real-time imaging within the practitioner's visual field. We evaluated the feasibility of using head-mounted display technology to improve ergonomics in ultrasound-guided regional anesthesia in a simulated environment. Two anesthesiologists performed an equal number of ultrasound-guided popliteal-sciatic nerve blocks using the head-mounted display on a porcine hindquarter, and an independent observer assessed each practitioner's ergonomics (eg, head turning, arching, eye movements, and needle manipulation) and the overall block quality based on the injectate spread around the target nerve for each procedure. Both practitioners performed their procedures without directly viewing the ultrasound monitor, and neither practitioner showed poor ergonomic behavior. Head-mounted display technology may offer potential advantages during ultrasound-guided regional anesthesia.

  2. An optimum method for pulsed high intensity focused ultrasound treatment of large volumes using the InSightec ExAblate (registered) 2000 system

    Energy Technology Data Exchange (ETDEWEB)

    O' Neill, B E; Karmonik, C; Li, K C P, E-mail: beoneill@tmhs.or [The Methodist Hospital Research Institute, 6565 Fannin, Houston TX 77030 (United States)

    2010-11-07

    Pulsed high intensity focused ultrasound (pHIFU) is a method for delivering ultrasound to tissue while avoiding high temperatures. The technique has been suggested for non-destructively enhancing local uptake of drugs. Side effects include thermal necrosis; therefore, real-time monitoring of tissue temperature is advantageous. This paper outlines a method for improving the treatment efficiency of pHIFU using the MR image-guided InSightec ExAblate (registered) 2000 system, an ultrasound system integrated into a whole body human MRI scanner with the ability to measure temperature at the treatment location in near real time. Thermal measurements obtained during treatment of a tissue phantom were used to determine appropriate heating parameters, and compared to in vivo treatment of rabbit muscle. Optimization of the treatment procedure and ultrasound transducer steering patterns was then conducted with the goal of minimizing treatment time while avoiding overheating. The optimization was performed on the basis of approximate solutions to the standard bioheat equation. The commercial system software of the Exablate (registered) system was modified to assist in this optimization. Depending on the size of the treatment volume, the presented results demonstrate that it is possible to use the technique described to cut treatment times significantly, up to one-third of that required by the current standard treatment cycle.

  3. Contrast-Enhanced Ultrasound Guided Biopsy of Undetermined Abdominal Lesions: A Multidisciplinary Decision-Making Approach

    Directory of Open Access Journals (Sweden)

    Feng Mao

    2017-01-01

    Full Text Available Aim. To investigate the value of contrast-enhanced ultrasound (CEUS guided biopsy of undetermined abdominal lesions in multidisciplinary treatment (MDT decision-making approach. Methods. Between Jan 2012 and Dec 2015, 60 consecutive patients (male, 37; female, 23; mean age, 51.3 years ± 14.6 who presented with undetermined abdominal lesions were included. CEUS and core needle percutaneous biopsy was performed under real-time CEUS guidance in all lesions. Data were recorded and compared with conventional ultrasound (US guidance group (n=75. All CEUS findings and clinical data were evaluated in MDT. Results. CEUS enabled the delimitation of more (88.3% versus 41.3% and larger (14.1 ± 10.7 mm versus 32.3 ± 18.5 mm nonenhanced necrotic areas. More inner (20.0% versus 6.7% and surrounding (18.3% versus 2.7% major vessels were visualized and avoided during biopsies. CEUS-guided biopsy increased the diagnostic accuracy from 93.3% to 98.3%, with correct diagnosis in 57 of 60 lesions (95.0%. The therapeutic plan was influenced by CEUS guided biopsies findings in the majority of patients (98.3%. Conclusion. The combination of CEUS guided biopsy and MDT decision-making approach is useful in the diagnostic work-up and therapeutic management.

  4. Contrast-Enhanced Ultrasound Guided Biopsy of Undetermined Abdominal Lesions: A Multidisciplinary Decision-Making Approach.

    Science.gov (United States)

    Mao, Feng; Dong, Yi; Ji, Zhengbiao; Cao, Jiaying; Wang, Wen-Ping

    2017-01-01

    Aim. To investigate the value of contrast-enhanced ultrasound (CEUS) guided biopsy of undetermined abdominal lesions in multidisciplinary treatment (MDT) decision-making approach. Methods. Between Jan 2012 and Dec 2015, 60 consecutive patients (male, 37; female, 23; mean age, 51.3 years ± 14.6) who presented with undetermined abdominal lesions were included. CEUS and core needle percutaneous biopsy was performed under real-time CEUS guidance in all lesions. Data were recorded and compared with conventional ultrasound (US) guidance group ( n = 75). All CEUS findings and clinical data were evaluated in MDT. Results. CEUS enabled the delimitation of more (88.3% versus 41.3%) and larger (14.1 ± 10.7 mm versus 32.3 ± 18.5 mm) nonenhanced necrotic areas. More inner (20.0% versus 6.7%) and surrounding (18.3% versus 2.7%) major vessels were visualized and avoided during biopsies. CEUS-guided biopsy increased the diagnostic accuracy from 93.3% to 98.3%, with correct diagnosis in 57 of 60 lesions (95.0%). The therapeutic plan was influenced by CEUS guided biopsies findings in the majority of patients (98.3%). Conclusion. The combination of CEUS guided biopsy and MDT decision-making approach is useful in the diagnostic work-up and therapeutic management.

  5. Evolution of Robot-assisted ultrasound-guided breast biopsy systems

    Directory of Open Access Journals (Sweden)

    Mustafa Z. Mahmoud

    2018-01-01

    Full Text Available Robot-assisted ultrasound-guided breast biopsy combines ultrasound (US imaging with a robotic system for medical interventions. This study was designed to provide a literature review of a robotic US-guided breast biopsy system to delineate its efficacious impact on current medical practice. In addition, the strengths and limitations of this approach were also addressed. Articles published in the English language between 2000 and 2016 were appraised in this review. A wide range of systems that bind robotics with US imaging and guided breast biopsy were examined in this article. The fundamental safety and real-time imaging capabilities of US, together with the accuracy and maneuverability of robotic devices, is clearly an effective association with unmatched capabilities. Numerous experimental systems have obvious benefits over old-fashioned techniques, and the future of robot-assisted US-guided breast biopsy will be characterized by increasing levels of automation, and they hold tremendous possibility to impact doctor achievement, patient recovery, and clinical management.

  6. Ultrasound-guided identification of cardiac imaging windows.

    Science.gov (United States)

    Liu, Garry; Qi, Xiu-Ling; Robert, Normand; Dick, Alexander J; Wright, Graham A

    2012-06-01

    Currently, the use of cine magnetic resonance imaging (MRI) to identify cardiac quiescent periods relative to the electrocardiogram (ECG) signal is insufficient for producing submillimeter-resolution coronary MR angiography (MRA) images. In this work, the authors perform a time series comparison between tissue Doppler echocardiograms of the interventricular septum (IVS) and concurrent biplane x-ray angiograms. Our results indicate very close agreement between the diastasis gating windows identified by both the IVS and x-ray techniques. Seven cath lab patients undergoing diagnostic angiograms were simultaneously scanned during a breath hold by ultrasound and biplane x-ray for six to eight heartbeats. The heart rate of each patient was stable. Dye was injected into either the left or right-coronary vasculature. The IVS was imaged using color tissue Doppler in an apical four-chamber view. Diastasis was estimated on the IVS velocity curve. On the biplane angiograms, proximal, mid, and distal regions were identified on the coronary artery (CA). Frame by frame correlation was used to derive displacement, and then velocity, for each region. The quiescent periods for a CA and its subsegments were estimated based on velocity. Using Pearson's correlation coefficient and Bland-Altman analysis, the authors compared the start and end times of the diastasis windows as estimated from the IVS and CA velocities. The authors also estimated the vessel blur across the diastasis windows of multiple sequential heartbeats of each patient. In total, 17 heartbeats were analyzed. The range of heart rate observed across patients was 47-79 beats per minute (bpm) with a mean of 57 bpm. Significant correlations (R > 0.99; p windows. The mean difference in the starting times between IVS and CA quiescent windows was -12.0 ms. The mean difference in end times between IVS and CA quiescent windows was -3.5 ms. In contrast, the correlation between RR interval and both the start and duration of the x

  7. Cost-Effectiveness of Mobile App-Guided Training in Extended Focused Assessment with Sonography for Trauma (eFAST)

    DEFF Research Database (Denmark)

    Nilsson, Philip Morkeberg; Todsen, Tobias; Subhi, Yousif

    2017-01-01

    the cost-effectiveness of mobile app-guided training versus traditional formats such as textbook-guided training. This study evaluated the cost-effectiveness of mobile app-guided versus textbook-guided ultrasound training. Material and methods First-year residents (n?=?38) with no previous ultrasound...... Structured Assessment of Ultrasound Skills (OSAUS) scale. The costs of developing mobile app and textbook material were calculated and used for the analysis of cost-effectiveness. Results 34 participants completed the transfer test. There was no statistically significant difference in test performance...... or diagnostic accuracy between the mobile app-guided (mean-OSAUS 42.3?% [95?%CI38.5?–?46.0?%]) and textbook-guided groups (mean-OSAUS 45.3?% [95?%CI39.3?–?51.3?%]) (d.f. [1.33]?=?0.45, p?=?0.41). However, development costs differed greatly for each instructional format. Textbook-guided training...

  8. AASHTO transportation asset management guide : a focus on implementation executive summary.

    Science.gov (United States)

    2013-06-01

    This AASHTO Transportation Asset Management Executive Summary serves as a companion to the AASHTO Transportation : Asset Management GuideA Focus on Implementation, which takes as a starting point the Transportation : Asset Management Guide publish...

  9. High-Intensity Focused Ultrasound (HIFU) in Uterine Fibroid Treatment: Review Study

    International Nuclear Information System (INIS)

    Mahmoud, Mustafa Z.; Alkhorayef, Mohammed; Alzimami, Khalid S.; Aljuhani, Manal Saud; Sulieman, Abdelmoneim

    2014-01-01

    High-intensity focused ultrasound (HIFU) is a highly precise medical procedure used locally to heat and destroy diseased tissue through ablation. This study intended to review HIFU in uterine fibroid therapy, to evaluate the role of HIFU in the therapy of leiomyomas as well as to review the actual clinical activities in this field including efficacy and safety measures beside the published clinical literature. An inclusive literature review was carried out in order to review the scientific foundation, and how it resulted in the development of extracorporeal distinct devices. Studies addressing HIFU in leiomyomas were identified from a search of the Internet scientific databases. The analysis of literature was limited to journal articles written in English and published between 2000 and 2013. In current gynecologic oncology, HIFU is used clinically in the treatment of leiomyomas. Clinical research on HIFU therapy for leiomyomas began in the 1990s, and the majority of patients with leiomyomas were treated predominantly with HIFUNIT 9000 and prototype single focus ultrasound devices. HIFU is a non-invasive and highly effective standard treatment with a large indication range for all sizes of leiomyomas, associated with high efficacy, low operative morbidity and no systemic side effects. Uterine fibroid treatment using HIFU was effective and safe in treating symptomatic uterine fibroids. Few studies are available in the literature regarding uterine artery embolization (UAE). HIFU provides an excellent option to treat uterine fibroids

  10. Multiple high-intensity focused ultrasound probes for kidney-tissue ablation.

    Science.gov (United States)

    Häcker, Axel; Chauhan, Sunita; Peters, Kristina; Hildenbrand, Ralf; Marlinghaus, Ernst; Alken, Peter; Michel, Maurice Stephan

    2005-10-01

    To investigate kidney-tissue ablation by high-intensity focused ultrasound (HIFU) using multiple and single probes. Ultrasound beams (1.75 MHz) produced by a piezoceramic element (focal distance 80 mm) were focused at the center of renal parenchyma. One of the three probes (mounted on a jig) could also be used for comparison with a single probe at comparable power ratings. Lesion dimensions were examined in perfused and unperfused ex vivo porcine kidneys at different power levels (40, 60, and 80 W) and treatment times (4, 6, and 8 seconds). At identical power levels, the lesions induced by multiple probes were larger than those induced by a single probe. Lesion size increased with increasing pulse duration and generator power. The sizes and shapes of the lesions were predictably repeatable in all samples. Lesions in perfused kidneys were smaller than those in unperfused kidneys. Ex vivo, kidney-tissue ablation by means of multiple HIFU probes offers significant advantages over single HIFU probes in respect of lesion size and formation. These advantages need to be confirmed by tests in vivo at higher energy levels.

  11. The role of ultrasound and ultrasound-guided fine needle aspiration biopsy of lymph nodes in patients with skin tumours

    International Nuclear Information System (INIS)

    Solivetti, Francesco Maria; Elia, Fulvia; Santaguida, Maria Giulia; Guerrisi, Antonino; Visca, Paolo; Cercato, Maria Cecilia; Di Carlo, Aldo

    2014-01-01

    The primary aim of this study was to evaluate the diagnostic accuracy of ultrasound (US) in the study of superficial lymph nodes during the follow-up of patients surgically treated for skin tumours. The secondary objective was to compare positive cytological results with histological reports. From 2004 to 2011, 480 patients (male/female: 285/195; median age 57 years; prevalent skin tumour