WorldWideScience

Sample records for accelerated focused ultrasound

  1. Focused Ultrasound and Lithotripsy.

    Science.gov (United States)

    Ikeda, Teiichiro; Yoshizawa, Shin; Koizumi, Norihiro; Mitsuishi, Mamoru; Matsumoto, Yoichiro

    2016-01-01

    Shock wave lithotripsy has generally been a first choice for kidney stone removal. The shock wave lithotripter uses an order of microsecond pulse durations and up to a 100 MPa pressure spike triggered at approximately 0.5-2 Hz to fragment kidney stones through mechanical mechanisms. One important mechanism is cavitation. We proposed an alternative type of lithotripsy method that maximizes cavitation activity to disintegrate kidney stones using high-intensity focused ultrasound (HIFU). Here we outline the method according to the previously published literature (Matsumoto et al., Dynamics of bubble cloud in focused ultrasound. Proceedings of the second international symposium on therapeutic ultrasound, pp 290-299, 2002; Ikeda et al., Ultrasound Med Biol 32:1383-1397, 2006; Yoshizawa et al., Med Biol Eng Comput 47:851-860, 2009; Koizumi et al., A control framework for the non-invasive ultrasound the ragnostic system. Proceedings of 2009 IEEE/RSJ International Conference on Intelligent Robotics and Systems (IROS), pp 4511-4516, 2009; Koizumi et al., IEEE Trans Robot 25:522-538, 2009). Cavitation activity is highly unpredictable; thus, a precise control system is needed. The proposed method comprises three steps of control in kidney stone treatment. The first step is control of localized high pressure fluctuation on the stone. The second step is monitoring of cavitation activity and giving feedback on the optimized ultrasound conditions. The third step is stone tracking and precise ultrasound focusing on the stone. For the high pressure control we designed a two-frequency wave (cavitation control (C-C) waveform); a high frequency ultrasound pulse (1-4 MHz) to create a cavitation cloud, and a low frequency trailing pulse (0.5 MHz) following the high frequency pulse to force the cloud into collapse. High speed photography showed cavitation collapse on a kidney stone and shock wave emission from the cloud. We also conducted in-vitro erosion tests of model and natural

  2. Prostate Focused Ultrasound Therapy.

    Science.gov (United States)

    Chapelon, Jean-Yves; Rouvière, Olivier; Crouzet, Sébastien; Gelet, Albert

    2016-01-01

    The tremendous progress in engineering and computing power coupled with ultrasound transducer technology and imaging modalities over the past 20 years have encouraged a revival of clinical interest in ultrasound therapy, mainly in High-Intensity Focused Ultrasound (HIFU). So far, the most extensive results from HIFU obtained in urology involve transrectal prostate ablation, which appears to be an effective therapeutic alternative for patients with malignant prostate tumors. Prostate cancer (PCa) is one of the most frequently diagnosed cancers in men. Several treatment options with different therapeutic approaches exist, including HIFU for localized PCa that has been in use for over 15 years. Since the early 2000s, two systems have been marketed for this application, and other devices are currently in clinical trials. HIFU treatment can be used either alone or in combination with (before- or after-) external beam radiotherapy (EBRT) (before or after HIFU) and can be repeated multiple times. HIFU treatment is performed under real-time monitoring with ultrasound or guided by MRI. Two indications are validated today: Primary care treatment and EBRT failure. The results of HIFU for primary care treatment are similar to standard conformal EBRT, even though no randomized comparative studies have been performed and no 10-year follow up data is yet available for HIFU. Salvage HIFU after EBRT failure is increasing with oncological outcomes, similar to those achieved with surgery but with the advantage of fewer adverse effects. HIFU is an evolving technology perfectly adapted for focal treatment. Thus, HIFU focal therapy is another pathway that must be explored when considering the accuracy and reliability for PCa mapping techniques. HIFU would be particularly suited for such a therapy since it is clear that HIFU outcomes and toxicity are relative to the volume of prostate treated. PMID:26486330

  3. 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.

  4. Geometrically focused neutral beam accelerators

    International Nuclear Information System (INIS)

    A more reliable 40 kV, 65 A power supply drain at 0.4 A/cm2, neutral-beam accelerator was developed for the Tandem Mirror Experiment (TMX). Multiple slotted aperture grids of 60% transparency are fabricated from refractory metal wires mounted to form a spherical surface. This geometrically focuses the beam by aiming individual beamlets at the center of curvature of the spherical grid (r = 3.2 m). We attain greater reliability and faster conditioning with geometrical focusing than with the previous technique of electrostatically steering beamlets to a common point. Electrostatic steering, accomplished by offsetting grid wires, is satisfactory if the offset of a beamlet is much less than the distance from the beamlet to the grids. It was found that Pierce Angle entrance grids performed better if sharper edged. A redesigned accelerator grid support structure reduced the number of ceramic-to-metal vacuum joints, and eliminated O rings between precisely aligned parts. The suppressor grid feedthrough is required to withstand a maximum voltage of 15 kV occurring during breakdown, greatly exceeding the operating voltage of 1.5 kV. Convenient fabrication and assembly techniques have been developed. Assembly of accelerators and plasma sources in a clean room appears to reduce the conditioning time. Following the successful testing of the prototype, eight 40 kV accelerators were built for TMX. Furthermore, ten 20 kV versions were built that are modifiable to 40 kV by exchanging the entrance grid

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

    International Nuclear Information System (INIS)

    To demonstrate the feasibility of CT and B-mode Ultrasound (US) targeted HIFU, a prototype coaxial focused ultrasound transducer was registered and integrated to a CT scanner. CT and diagnostic ultrasound were used for HIFU targeting and monitoring, with the goals of both thermal ablation and non-thermal enhanced drug delivery. A 1 megahertz coaxial ultrasound transducer was custom fabricated and attached to a passive position-sensing arm and an active six degree-of-freedom robotic arm via a CT stereotactic frame. The outer therapeutic transducer with a 10 cm fixed focal zone was coaxially mounted to an inner diagnostic US transducer (2-4 megahertz, Philips Medical Systems). This coaxial US transducer was connected to a modified commercial focused ultrasound generator (Focus Surgery, Indianapolis, IN) with a maximum total acoustic power of 100 watts. This pre-clinical paradigm was tested for ability to heat tissue in phantoms with monitoring and navigation from CT and live US. The feasibility of navigation via image fusion of CT with other modalities such as PET and MRI was demonstrated. Heated water phantoms were tested for correlation between CT numbers and temperature (for ablation monitoring). The prototype transducer and integrated CT/US imaging system enabled simultaneous multimodality imaging and therapy. Pre-clinical phantom models validated the treatment paradigm and demonstrated integrated multimodality guidance and treatment monitoring. Temperature changes during phantom cooling corresponded to CT number changes. Contrast enhanced or non-enhanced CT numbers may potentially be used to monitor thermal ablation with HIFU. Integrated CT, diagnostic US, and therapeutic focused ultrasound bridges a gap between diagnosis and therapy. Preliminary results show that the multimodality system may represent a relatively inexpensive, accessible, and simple method of both targeting and monitoring HIFU effects. Small animal pre-clinical models may be translated to large

  6. High-Intensity Focused Ultrasound Therapy: an Overview for Radiologists

    OpenAIRE

    Kim, Young-sun; Rhim, Hyunchul; Choi, Min Joo; Lim, Hyo Keun; Choi, Dongil

    2008-01-01

    High-intensity focused ultrasound therapy is a novel, emerging, therapeutic modality that uses ultrasound waves, propagated through tissue media, as carriers of energy. This completely non-invasive technology has great potential for tumor ablation as well as hemostasis, thrombolysis and targeted drug/gene delivery. However, the application of this technology still has many drawbacks. It is expected that current obstacles to implementation will be resolved in the near future. In this review, w...

  7. Effect of Tissue Inhomogeneity on Nonlinear Propagation of Focused Ultrasound

    Institute of Scientific and Technical Information of China (English)

    LIU Zhen-Bo; FAN Ting-Bo; GUO Xia-Sheng; ZHANG Dong

    2010-01-01

    @@ We study the influence of tissue inhomogeneity on the focused ultrasound based on the phase screen model and the acoustic nonlinear equation.The inhomogeneous tissue is considered as a combination of a homogeneous medium and a phase aberration screen.Six polyethylene(PE)plates with various correlation lengths and standard deviations are made to mimic the inhomogeneity induced by the human body abdominal.Results indicate that the correlation length affects the side lobe structure of the beam pattern; while the standard deviation is associated with the focusing capability.This study provides a theoretical and experimental basis for the development of a precise treatment plan for high intensity focused ultrasound.

  8. An Rf Focused Interdigital Ion Accelerating Structure

    International Nuclear Information System (INIS)

    An Rf Focused Interdigital (RFI) ion accelerating structure will be described. It represents an effective combination of the Wideroee (or interdigital) linac structure, used for many low frequency, heavy ion applications, and the rf electric quadrupole focusing used in the RFQ and RFD linac structures. As in the RFD linac structure, rf focusing is introduced into the RFI linac structure by configuring the drift tubes as two independent pieces operating at different electrical potentials as determined by the rf fields of the linac structure. Each piece (or electrode) of the RFI drift tube supports two fingers pointed inwards towards the opposite end of the drift tube forming a four-finger geometry that produces an rf quadrupole field along the axis of the linac for focusing the beam. However, because of the differences in the rf field configuration along the axis, the scheme for introducing rf focusing into the interdigital linac structure is quite different from that adopted for the RFD linac structure. The RFI linac structure promises to have significant size, efficiency, performance, and cost advantages over existing linac structures for the acceleration of low energy ion beams of all masses (light to heavy). These advantages will be reviewed. A 'cold model' of this new linac structure has been fabricated and the results of rf cavity measurements on this cold model will be presented

  9. Spatial filters for focusing ultrasound images

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gori, Paola

    2001-01-01

    Traditionally focusing is done by taking out one sample in the received signal from each transducer element and then sum these signals. This method does not take into account the temporal or spatial spread of the received signal from a point scatterer and does not make an optimal focus of the data......, 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...... for beamforming the received RF signals from the individual transducer elements. The matched filter is applied on RF signals from individual transducer elements, thus properly taking into account the spatial spread of the received signal. The method can be applied to any transducer and can also be used...

  10. Investigation of Manipulation Technique of Microbubbles Using Focused Ultrasound.

    Science.gov (United States)

    Osaki, Taichi; Inoue, Kazuhito; Matsumoto, Yoichiro; Takagi, Shu; Azuma, Takashi; Ichiyanagi, Mitsuhisa

    2015-11-01

    Recently, it has been thought that the application of ultrasound and microbubbles(MB) is utility to the medical field. Should MB be manipulated contactlessly, it will contribute to the mechanism investigation on the drug delivery system using MB as drug carrier. However no technique has yet to be established that can trap MB at any desired position, manipulate them along any desired path. Accordingly in this research, we investigated whether it was possible to trap MB at desired position, manipulate them along desired paths through experiments aimed at the development of MB manipulation tools that utilize ultrasound. Moreover, we analyzed the microbubble behaviors in ultrasound field. Bubbles in the ultrasound wave field are subjected to the primary Bjerknes force. Our method aimed that MB are trapped at the antinode or the node and manipulated with moving the antinode or node. We fabricated a concave transducer which radiates focused ultrasound and used sonazoid as MB and they were trapped at the focus as a cluster. The transducer moves its own position to move its focus and manipulate MB. Besides, we observed the trapped cluster with several incident frequencies. MB were trapped and manipulated along a locus of alphabet ?M? about 100 µm. From this result, it is implied that MB can be manipulated along any desired path. Moreover, there was the inverse correlation between the trapped cluster size and the incident frequency.

  11. High-Intensity Focused Ultrasound Therapy: an Overview for Radiologists

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Sun; Rhim, Hyun Chul; Lim, Hyo Keun; Choi, Dong Il [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Choi, Min Joo [College of Medicine, Cheju National University, Jeju (Korea, Republic of)

    2008-08-15

    High-intensity focused ultrasound therapy is a novel, emerging, therapeutic modality that uses ultrasound waves, propagated through tissue media, as carriers of energy. This completely non-invasive technology has great potential for tumor ablation as well as hemostasis, thrombolysis and targeted drug/gene delivery. However, the application of this technology still has many drawbacks. It is expected that current obstacles to implementation will be resolved in the near future. In this review, we provide an overview of high-intensity focused ultrasound therapy from the basic physics to recent clinical studies with an interventional radiologist's perspective for the purpose of improving the general understanding of this cutting-edge technology as well as speculating on future developments

  12. Adverse Events of Extracorporeal Ultrasound-Guided High Intensity Focused Ultrasound Therapy

    OpenAIRE

    Tinghe Yu; Jun Luo

    2011-01-01

    BACKGROUND: High-intensity focused ultrasound (HIFU) is considered to be an alternative to surgery. Extracorporeal ultrasound-guided HIFU (USgFU) has been clinically used to treat solid tumors. Preliminary trials in a small sample of a Western population suggested that this modality was safe. Most trials are performed in China thereby providing comprehensive data for understanding the safety profile. The aim of this study was to evaluate adverse events of USgFU therapy. METHODS AND FINDINGS: ...

  13. Controlled Hyperthermia with MRI-guided Focused Ultrasound

    DEFF Research Database (Denmark)

    Hokland, Steffen; Salomir, Rares; Pedersen, Michael

    doses sufficient to induce cellular deactivation thermotherapy is still regarded as an experimental treatment. In contrast to other thermo-therapeutic modalities Focused Ultrasound (FUS) may be employed non-invasively to deliver a highly localized thermal build-up in deep seated regions of the body...... is the vulnerability to motion-artifacts, baseline drift and the fact that the PRF in lipids is independent of temperature. FUS-technology: At moderate intensities absorption of ultrasound (US) in tissue results in a local increase in temperature. As in other wave phenomena the extent of the focal point...

  14. Design and Fabrication of Double-Focused Ultrasound Transducers to Achieve Tight Focusing.

    Science.gov (United States)

    Jang, Jihun; Chang, Jin Ho

    2016-01-01

    Beauty treatment for skin requires a high-intensity focused ultrasound (HIFU) transducer to generate coagulative necrosis in a small focal volume (e.g., 1 mm³) placed at a shallow depth (3-4.5 mm from the skin surface). For this, it is desirable to make the F-number as small as possible under the largest possible aperture in order to generate ultrasound energy high enough to induce tissue coagulation in such a small focal volume. However, satisfying both conditions at the same time is demanding. To meet the requirements, this paper, therefore, proposes a double-focusing technique, in which the aperture of an ultrasound transducer is spherically shaped for initial focusing and an acoustic lens is used to finally focus ultrasound on a target depth of treatment; it is possible to achieve the F-number of unity or less while keeping the aperture of a transducer as large as possible. In accordance with the proposed method, we designed and fabricated a 7-MHz double-focused ultrasound transducer. The experimental results demonstrated that the fabricated double-focused transducer had a focal length of 10.2 mm reduced from an initial focal length of 15.2 mm and, thus, the F-number changed from 1.52 to 1.02. Based on the results, we concluded that the proposed double-focusing method is suitable to decrease F-number while maintaining a large aperture size. PMID:27509500

  15. Design and Fabrication of Double-Focused Ultrasound Transducers to Achieve Tight Focusing

    Science.gov (United States)

    Jang, Jihun; Chang, Jin Ho

    2016-01-01

    Beauty treatment for skin requires a high-intensity focused ultrasound (HIFU) transducer to generate coagulative necrosis in a small focal volume (e.g., 1 mm3) placed at a shallow depth (3–4.5 mm from the skin surface). For this, it is desirable to make the F-number as small as possible under the largest possible aperture in order to generate ultrasound energy high enough to induce tissue coagulation in such a small focal volume. However, satisfying both conditions at the same time is demanding. To meet the requirements, this paper, therefore, proposes a double-focusing technique, in which the aperture of an ultrasound transducer is spherically shaped for initial focusing and an acoustic lens is used to finally focus ultrasound on a target depth of treatment; it is possible to achieve the F-number of unity or less while keeping the aperture of a transducer as large as possible. In accordance with the proposed method, we designed and fabricated a 7-MHz double-focused ultrasound transducer. The experimental results demonstrated that the fabricated double-focused transducer had a focal length of 10.2 mm reduced from an initial focal length of 15.2 mm and, thus, the F-number changed from 1.52 to 1.02. Based on the results, we concluded that the proposed double-focusing method is suitable to decrease F-number while maintaining a large aperture size. PMID:27509500

  16. Acceleration and Focusing of Plasma Flows

    Science.gov (United States)

    Griswold, Martin E.

    The acceleration of flowing plasmas is a fundamental problem that is useful in a wide variety of technological applications. We consider the problem from the perspective of plasma propulsion. Gridded ion thrusters and Hall thrusters are the most commonly used devices to create flowing plasma for space propulsion, but both suffer from fundamental limitations. Gridded ion sources create good quality beams in terms of energy spread and spatial divergence, but the Child-Langmuir law in the non-neutral acceleration region limits the maximum achievable current density. Hall thrusters avoid this limitation by accelerating ions in quasi-neutral plasma but, as a result, produce plumes with high spatial divergence and large energy spread. In addition the more complicated magnetized plasma in the Hall Thruster produces oscillations that can reduce the efficiency of the thruster by increasing electron transport to the anode. We present investigations of three techniques to address the fundamental limitations on the performance of each thruster. First, we propose a method to increase the time-averaged current density (and thus thrust density) produced by a gridded ion source above the Child-Langmuir limit by introducing time-varying boundary conditions. Next, we use an electrostatic plasma lens to focus the Hall thruster plume, and finally we develop a technique to suppress a prominent oscillation that degrades the performance of Hall thrusters. The technique to loosen the constraints on current density from gridded ion thrusters actually applies much more broadly to any space charge limited flow. We investigate the technique with a numerical simulation and by proving a theoretical upper bound. While we ultimately conclude that the approach is not suitable for space propulsion, our results proved useful in another area, providing a benchmark for research into the spontaneously time-dependent current that arises in microdiodes. Next, we experimentally demonstrate a novel

  17. Microwave thermal imaging of scanned focused ultrasound heating: animal experiments

    Science.gov (United States)

    Zhou, Tian; Meaney, Paul M.; Hoopes, P. Jack; Geimer, Shireen D.; Paulsen, Keith D.

    2011-03-01

    High intensity focused ultrasound (HIFU) uses focused ultrasound beams to ablate localized tumors noninvasively. Multiple clinical trials using HIFU treatment of liver, kidney, breast, pancreas and brain tumors have been conducted, while monitoring the temperature distribution with various imaging modalities such as MRI, CT and ultrasound. HIFU has achieved only minimal acceptance partially due to insufficient guidance from the limited temperature monitoring capability and availability. MR proton resonance frequency (PRF) shift thermometry is currently the most effective monitoring method; however, it is insensitive in temperature changes in fat, susceptible to motion artifacts, and is high cost. Exploiting the relationship between dielectric properties (i.e. permittivity and conductivity) and tissue temperature, in vivo dielectric property distributions of tissue during heating were reconstructed with our microwave tomographic imaging technology. Previous phantom studies have demonstrated sub-Celsius temperature accuracy and sub-centimeter spatial resolution in microwave thermal imaging. In this paper, initial animal experiments have been conducted to further investigate its potential. In vivo conductivity changes inside the piglet's liver due to focused ultrasound heating were observed in the microwave images with good correlation between conductivity changes and temperature.

  18. Focusing of ferroelectret air-coupled ultrasound transducers

    Science.gov (United States)

    Gaal, Mate; Bartusch, Jürgen; Dohse, Elmar; Schadow, Florian; Köppe, Enrico

    2016-02-01

    Air-coupled ultrasound has been applied increasingly as a non-destructive testing method for lightweight construction in recent years. It is particularly appropriate for composite materials being used in automotive and aviation industry. Air-coupled ultrasound transducers mostly consist of piezoelectric materials and matching layers. However, their fabrication is challenging and their signal-to-noise ratio often not sufficient for many testing requirements. To enhance the efficiency, air-coupled ultrasound transducers made of cellular polypropylene have been developed. Because of its small density and sound velocity, this piezoelectric ferroelectret matches the small acoustic impedance of air much better than matching layers applied in conventional transducers. In our contribution, we present two different methods of spherical focusing of ferroelectret transducers for the further enhancement of their performance in NDT applications. Measurements on carbon-fiber-reinforced polymer (CFRP) samples and on metal adhesive joints performed with commercially available focused air-coupled ultrasound transducers are compared to measurements executed with self-developed focused ferroelectret transducers.

  19. 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

  20. Numerical simulations of clinical focused ultrasound functional neurosurgery

    International Nuclear Information System (INIS)

    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

  1. Noninvasive measurement of local thermal diffusivity using backscattered ultrasound and focused ultrasound heating.

    Science.gov (United States)

    Anand, Ajay; Kaczkowski, Peter J

    2008-09-01

    Previously, noninvasive methods of estimating local tissue thermal and acoustic properties using backscattered ultrasound have been proposed in the literature. In this article, a noninvasive method of estimating local thermal diffusivity in situ during focused ultrasound heating using beamformed acoustic backscatter data and applying novel signal processing techniques is developed. A high intensity focused ultrasound (HIFU) transducer operating at subablative intensities is employed to create a brief local temperature rise of no more than 10 degrees C. Beamformed radio-frequency (RF) data are collected during heating and cooling using a clinical ultrasound scanner. Measurements of the time-varying "acoustic strain", that is, spatiotemporal variations in the RF echo shifts induced by the temperature related sound speed changes, are related to a solution of the heat transfer equation to estimate the thermal diffusivity in the heated zone. Numerical simulations and experiments performed in vitro in tissue mimicking phantoms and excised turkey breast muscle tissue demonstrate agreement between the ultrasound derived thermal diffusivity estimates and independent estimates made by a traditional hot-wire technique. The new noninvasive ultrasonic method has potential applications in thermal therapy planning and monitoring, physiological monitoring and as a means of noninvasive tissue characterization. PMID:18450361

  2. High intensity focused ultrasound in clinical tumor ablation

    OpenAIRE

    Zhou, Yu-Feng

    2011-01-01

    Recent advances in high intensity focused ultrasound (HIFU), which was developed in the 1940s as a viable thermal tissue ablation approach, have increased its popularity. In clinics, HIFU has been applied to treat a variety of solid malignant tumors in a well-defined volume, including the pancreas, liver, prostate, breast, uterine fibroids, and soft-tissue sarcomas. In comparison to conventional tumor/cancer treatment modalities, such as open surgery, radio- and chemo-therapy, HIFU has the ad...

  3. Salvage radiotherapy after high intensity focused ultrasound for prostate cancer

    OpenAIRE

    Dickinson, Peter; Sundar, Santhanam

    2012-01-01

    High-intensity focused ultrasound (HIFU) is a technique that has been used to treat localised prostate cancer. There is no standard treatment for patients who relapse with prostate cancer following primary treatment with HIFU; here we report the case of a patient who was successfully treated with external beam radiotherapy for disease relapse following HIFU. To date, our patient remains disease free with no toxicity from his treatment.

  4. Nakagami imaging for detecting thermal lesions induced by high-intensity focused ultrasound in tissue.

    Science.gov (United States)

    Rangraz, Parisa; Behnam, Hamid; Tavakkoli, Jahan

    2014-01-01

    High-intensity focused ultrasound induces focalized tissue coagulation by increasing the tissue temperature in a tight focal region. Several methods have been proposed to monitor high-intensity focused ultrasound-induced thermal lesions. Currently, ultrasound imaging techniques that are clinically used for monitoring high-intensity focused ultrasound treatment are standard pulse-echo B-mode ultrasound imaging, ultrasound temperature estimation, and elastography-based methods. On the contrary, the efficacy of two-dimensional Nakagami parametric imaging based on the distribution of the ultrasound backscattered signals to quantify properties of soft tissue has recently been evaluated. In this study, ultrasound radio frequency echo signals from ex vivo tissue samples were acquired before and after high-intensity focused ultrasound exposures and then their Nakagami parameter and scaling parameter of Nakagami distribution were estimated. These parameters were used to detect high-intensity focused ultrasound-induced thermal lesions. Also, the effects of changing the acoustic power of the high-intensity focused ultrasound transducer on the Nakagami parameters were studied. The results obtained suggest that the Nakagami distribution's scaling and Nakagami parameters can effectively be used to detect high-intensity focused ultrasound-induced thermal lesions in tissue ex vivo. These parameters can also be used to understand the degree of change in tissue caused by high-intensity focused ultrasound exposures, which could be interpreted as a measure of degree of variability in scatterer concentration in various parts of the high-intensity focused ultrasound lesion. PMID:24264647

  5. The thresholds and mechanisms of tissue injury by focused ultrasound

    Science.gov (United States)

    Simon, Julianna

    Therapeutic ultrasound is used in clinics around the world to treat ailments such as uterine fibroids, kidney stones, and plantar fasciitis. While many of the therapeutic effects of ultrasound are elicited by hyperthermia, bubbles can also interact with tissue to produce beneficial effects. For example, bubbles are used in boiling histotripsy to de-bulk tissue and are used in shock wave lithotripsy to break kidney stones. However, the same bubbles that break the kidney stones also damage the kidney, which is why bubble damage is a concern in every ultrasound application including fetal imaging. Whether the aim is to emulsify a tumor or image a fetus, understanding the thresholds and mechanisms of tissue injury by bubbles in an ultrasound field is important for all ultrasound applications and was the goal of this dissertation. One specific application of therapeutic ultrasound, known as boiling histotripsy, uses shock wave heating to explosively expand a millimeter-size boiling bubble at the transducer focus and fractionate bulk tissue. Yet it was unclear how the millimeter-size boiling or vapor bubble broke down the tissue into its submicron components. In this dissertation, we experimentally tested the hypothesis that ultrasonic atomization, or the emission of fine droplets from an acoustically excited liquid film, is the mechanism by which the millimeter-size boiling bubble in boiling histotripsy fractionates tissue into its submicron components. Using high speed photography, we showed that tissue can behave as a liquid such that a miniature acoustic fountain forms and atomization occurs within a millimeter-size cavity that approximates the boiling or vapor bubble produced by boiling histotripsy. The end result of tissue atomization was a hole in the tissue surface. After showing that tissue can be eroded by atomization, a series of experiments were conducted to determine the tissue properties that influence atomization. The results indicated that highly

  6. Ultrasound- and MR-guided focused ultrasound surgery for prostate cancer

    OpenAIRE

    Zini, Chiara; Hipp, Elisabeth; Thomas, Stephen; Napoli, Alessandro; Catalano, Carlo; Oto, Aytekin

    2012-01-01

    Prostate cancer (PC) is one of the most frequently diagnosed cancers in men. There are a number of treatment options for PC with a different therapeutic approach between USA and Europe. Radical prostatectomy is one of the most used therapies but focal gland therapy is an emerging approach, especially for localized tumors. In this scenario, high intensity focused ultrasound (HIFU) has been incorporated in certain medical association guidelines. HIFU has been employed for about 10 years especia...

  7. Enhancement of accelerated carbonation of alkaline waste residues by ultrasound.

    Science.gov (United States)

    Araizi, Paris K; Hills, Colin D; Maries, Alan; Gunning, Peter J; Wray, David S

    2016-04-01

    The continuous growth of anthropogenic CO2 emissions into the atmosphere and the disposal of hazardous wastes into landfills present serious economic and environmental issues. Reaction of CO2 with alkaline residues or cementitius materials, known as accelerated carbonation, occurs rapidly under ambient temperature and pressure and is a proven and effective process of sequestering the gas. Moreover, further improvement of the reaction efficiency would increase the amount of CO2 that could be permanently sequestered into solid products. This paper examines the potential of enhancing the accelerated carbonation of air pollution control residues, cement bypass dust and ladle slag by applying ultrasound at various water-to-solid (w/s) ratios. Experimental results showed that application of ultrasound increased the CO2 uptake by up to four times at high w/s ratios, whereas the reactivity at low water content showed little change compared with controls. Upon sonication, the particle size of the waste residues decreased and the amount of calcite precipitates increased. Finally, the sonicated particles exhibited a rounded morphology when observed by scanning electron microscopy. PMID:26905698

  8. Use of High Intensity Focused Ultrasound for Treating Malignant Tumors

    Institute of Scientific and Technical Information of China (English)

    WenzhiChen; ZhibiaoWang; FengWu; JinBai; HuiZhu; JianzhongZou; KequanLi; FanglinXie; ZhilongWang

    2004-01-01

    OBJECTIVE To investigate the efficacy and side effects of high intensity focused ultrasound(HIFU) in the treatment of malignant solid tumors. METHODS Thirty patients who refused surgery and/or were refractory to chemotherapy were treated by HIFU alone, with the efficacy and side effects monitored as follows: observation of vital organ signs; functional assay of important organs; imaging examinations including: digital subtraction angiography (DSA), CT, MRI, single photon emission computed tomography (SPECT), large core needle biopsy, complications and metastasis. RESULTS After HIFU therapy, the vital signs remained stable and the functions of the heart, lung, kidney and liver were also normal. DSA images showed that small or larger arteries were not damaged. After a follow-up of 10-38 months(mean 23.1 months), 26 patients(87%) were alive. The volume of the tumor underwent complete regression in 10 patients. Shrinkage of the tumor volume ≥50% was observed in 13 patients. Eight of 13 patients were examined by large core needle biopsy, all showing necrosis and/or fibrosis though 3 patients(10%) had local recurrence. Two of these were retreated again by HIFU and the locally recurrent tumors were controlled. New metastases developed in 5 patients after H IFU. Two patients suffered from peripheral nerve injuriy and they have recovered during the follow-up. One patient developed skin injury. CONCLUSION High intensity focused ultrasound is effective and safe in the treatment of malignant solid tumors.

  9. Phase Relation of Harmonics in Nonlinear Focused Ultrasound

    Institute of Scientific and Technical Information of China (English)

    Zhe-Fan Peng; Wei-Jun Lin; Shi-Lei Liu; Chang Su; Hai-Lan Zhang; Xiu-Ming Wang

    2016-01-01

    The phase relation of harmonics in high-intensity focused ultrasound is investigated numerically and experimentally.The nonlinear Westervelt equation is solved to model nonlinear focused sound field by using the finite difference time domain method.Experimental waveforms are measured by a robust needle hydrophone.Then the relative phase quantity is introduced and obtained by using the zero-phase filter.The results show that the nth harmonic relative phase quantity is approximately (n-1)π/3 at geometric center and increases along the axial direction.Moreover,the relative phase quantity decreases with the increase of source amplitude.This phase relation gives an explanation of some nonlinear phenomena such as the discrepancy of positive and negative pressure.

  10. Ultrasound imaging and evaluation of lesion induced by High Intensity Focused Ultrasound

    Institute of Scientific and Technical Information of China (English)

    ZHONG Hui; WAN Mingxi; JIANG Yifeng; WANG Supin

    2006-01-01

    The present study was to investigate the differential imaging method for detecting HIFU (High Intensity Focused Ultrasound)-induced lesions and the estimation of variation of attenuation for lesion evaluation with log spectral difference algorithm. Experiment results of bovine muscle and liver in vitro were acquired. Several algorithms for lesion detection - Absolute Difference (AD), Sum Absolute Differences (SAD) and Sum Squared Differences (SSD) - were analyzed with several window sizes and threshold values. Then three attenuation parameters were compared to evaluate the degree of tissue damage. It was found that variation of the mean attenuation △(α) was an effective parameter to evaluate lesions.

  11. In Vivo application and localization of transcranial focused ultrasound using dual-mode ultrasound arrays.

    Science.gov (United States)

    Haritonova, Alyona; Liu, Dalong; Ebbini, Emad S

    2015-12-01

    Focused ultrasound (FUS) has been proposed for a variety of transcranial applications, including neuromodulation, tumor ablation, and blood-brain barrier opening. A flurry of activity in recent years has generated encouraging results demonstrating its feasibility in these and other applications. To date, monitoring of FUS beams has been primarily accomplished using MR guidance, where both MR thermography and elastography have been used. The recent introduction of real-time dual-mode ultrasound array (DMUA) systems offers a new paradigm in transcranial focusing. In this paper, we present first experimental results of ultrasound-guided transcranial FUS (tFUS) application in a rodent brain, both ex vivo and in vivo. DMUA imaging is used for visualization of the treatment region for placement of the focal spot within the brain. This includes the detection and localization of pulsating blood vessels at or near the target point(s). In addition, DMUA imaging is used to monitor and localize the FUS-tissue interactions in real time. In particular, a concave (40 mm radius of curvature), 32-element, 3.5-MHz DMUA prototype was used for imaging and tFUS application in ex vivo and in vivo rat models. The ex vivo experiments were used to evaluate the point spread function of the transcranial DMUA imaging at various points within the brain. In addition, DMUA-based transcranial ultrasound thermography measurements were compared with thermocouple measurements of subtherapeutic tFUS heating in rat brain ex vivo. The ex vivo setting was also used to demonstrate the capability of DMUA to produce localized thermal lesions. The in vivo experiments were designed to demonstrate the ability of the DMUA to apply, monitor, and localize subtherapeutic tFUS patterns that could be beneficial in transient blood-brain barrier opening. The results show that although the DMUA focus is degraded due to the propagation through the skull, it still produces localized heating effects within a sub

  12. Focused ultrasound induces apoptosis in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    GUO Qian; JIANG Li-xin; HU Bing

    2012-01-01

    Background The incidence and mortality rate of pancreatic cancer have increased dramatically in China over recent decades.Focused ultrasound (FU) has been somewhat successful in treating pancreatic cancer.The purpose of this study was to investigate apoptosis in pancreatic cancer cells induced by FU.Methods Suspension of human pancreatic carcinoma cell line PaTu 8988t was radiated by FU,using five doses with different radiation parameters and patterns,including one blank control.Temperature increase of the cell suspension was monitored.Cell apoptosis and death after FU radiation was observed using fluorescence microscopy and was tested by flow cytometer at 3,6,12,24,and 48 hours after ultrasound radiation.Results The maximum cell suspension temperatures following five radiation doses were 28°C,(42.20±2.17)°C,(50.80±0.84)°C,(55.80±2.17)°C,and (65.20±3.11)°C; differences between the doses were statistically significant (P <0.05).The apoptosis rate peaked at 24 hours after radiation,at (0.56±0.15)%,(1.28±0.16)%,(1.84±0.29)%,(5.74±1.15)%,and (2.00±0.84)% for the five doses; differences between the doses were statistically significant (P <0.05).Between doses 1-4,cell apoptosis rates increased as the Tmax increased.In dose 5,as the Tmax was above 60°C,the apoptosis rate decreased.Conclusion Sub-threshold thermal exposures of FU radiation with a continuous radiation pattern could result in higher oercentage of apoptosed cells.

  13. Echinococcus granulosus: protoscolicidal effect of high intensity focused ultrasound.

    Science.gov (United States)

    Zou, Xiaoyi; Wang, Junan; Zhao, Hailong; Zhang, Jing; Wu, Weihua; Ye, Bin

    2009-04-01

    High intensity focused ultrasound (HIFU) is a new non-invasive technique which can cause cell death and tissue necrosis by focusing high-energy ultrasonic waves on a single location. The aim of our work is to investigate the damaging effect of HIFU on Echinococcus granulosus protoscolices, as well as its inhibitory effect on growth of hydatid cysts derived from protoscolices. The damaging effect of HIFU on protoscolices was investigated by following parasite mortality after irradiation, while the inhibitory effect was investigated by infection experiments in vivo. The results demonstrated that HIFU was able to damage protoscolices and the protoscolicidal effect was dose-dependent and showed late-onset. The growth of protoscolices that survived the exposure to HIFU was obviously suppressed in vitro, and the mean weight of hydatid cysts resulting from such protoscolices in the experimental group was less than that in controls. Evidences including the protoscolicidal effect, fragmentized protoscolices and low post exposure temperatures, suggest that cavitation may contribute to the protoscolicidal effect of HIFU. In addition, the structure of the germinal membrane in cysts developing from the irradiated protoscolices was not as normal or intact as that from non-irradiated ones, and morphological changes related to degeneration were observed, suggesting that HIFU could prevent protoscolices from developing normal germinal membrane and consequently stop the proliferation of secondary hydatid cysts. HIFU demonstrated damaging effect on protoscolices, inhibited the growth of protoscolices in vitro and in vivo, and could be a possible therapeutic option for cystic echinococcosis.

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

    International Nuclear Information System (INIS)

    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

  15. 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.

  16. 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.

  17. Clinical Application of High-intensity Focused Ultrasound in Cancer Therapy

    OpenAIRE

    Hsiao, Yi-Hsuan; Kuo, Shou-Jen; Tsai, Horng-Der; Chou, Ming-Chih; Yeh, Guang-Perng

    2016-01-01

    The treatment of cancer is an important issue in both developing and developed countries. Clinical use of ultrasound in cancer is not only for the diagnosis but also for the treatment. Focused ultrasound surgery (FUS) is a noninvasive technique. By using the combination of high-intensity focused ultrasound (HIFU) and imaging method, FUS has the potential to ablate tumor lesions precisely. The main mechanisms of HIFU ablation involve mechanical and thermal effects. Recent advances in HIFU have...

  18. Effects of Dynamic Changes in Ultrasound Attenuation and Blood Perfusion on Lesion Formation of Multiple focus Pattern during Ultrasound Surgery

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chen-xi; BAI Jing-feng; CHEN Ya-zhu

    2007-01-01

    A nonlinear finite-element program was developed to simulate the dynamic evolution of coagulation in tissue considering temperature and thermal-dose dependence of the ultrasound attenuation and blood perfusion rate.The effects of these dynamic parameters on the lesion formation were investigated in the particular case of ultrasound hepatic ablation with bi-focus intensity pattern.The results of simulations were compared that incorporate dynamic changes of ultrasound attenuation and perfusion and results that neglect these effects.The result shows that thermal-dose-dependent ultrasound attenuation is the dominating factor in the full dynamic model.If the dynamic ultrasound attenuation is ignored, a relatively significant underestimation of the temperature rise appears in the focal plane and the region next to the focal plane, resulting in an underestimation in predicting diameter of coagulation.Higher heating intensity leads to greater underestimation.

  19. Extracorporeal High-Intensity Focused Ultrasound Treatment for Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    HuiZhu; FengWu; WenzhiChen; YoudeCao; JinBai; ZhibiaoWang

    2004-01-01

    OBJECTIVE To evaluate the clinical safety and efficacy of using highintensity focused ultrasound (HIFU) therapy, for breast cancer, and to select the appropriate methods in evaluating the therapeutic effects.METHODS A total of 24 patients with breast cancer underwent HIFU treatment 1-2 weeks before receiving modified radical mastectomy. During and after HIFU therapy, changes in blood pressure, breath, pulse and peripheral blood oxygen saturation were monitored. At the same time, the damage of the skin and tissue produced by HIFU at the target region was evaluated as well. Surgically excised samples were used for pathological examinations to evaluate the HIFU-induced destruction of the targeted tissue. Three patients received Tc-ECT and 1 MRI examinations before and after HIFU.RESULTS HIFU treatment had no apparent influence on either the tissue nearby the target or on vital signs of the patients. Pathological, tc-ECT and MRI examinations demonstrated that targeted tissue showed complete coagulative necrosis.CONCLUSION Under the guidance of real-time ultrasonic imaging, HIFU can effectively and safely destroy the breast cancer mass and 99MTc-ECT and MRI examination can be utilized to evaluate the therapeutic effects.HIFU may become one of the options for breast cancer therapy in the future.

  20. Adverse events of extracorporeal ultrasound-guided high intensity focused ultrasound therapy.

    Directory of Open Access Journals (Sweden)

    Tinghe Yu

    Full Text Available BACKGROUND: High-intensity focused ultrasound (HIFU is considered to be an alternative to surgery. Extracorporeal ultrasound-guided HIFU (USgFU has been clinically used to treat solid tumors. Preliminary trials in a small sample of a Western population suggested that this modality was safe. Most trials are performed in China thereby providing comprehensive data for understanding the safety profile. The aim of this study was to evaluate adverse events of USgFU therapy. METHODS AND FINDINGS: Clinical data were searched in 2 Chinese databases. Adverse events of USgFU were summarized and compared with those of magnetic resonance-guided HIFU (MRgFU; for uterine, bone or breast tumor and transrectal ultrasound-guided HIFU (for prostate cancer or benign prostate hyperplasia. USgFU treatment was performed using 7 types of device. Side effects were evaluated in 13262 cases. There were fewer adverse events in benign lesions than in malignant lesions (11.81% vs. 21.65%, p<0.0001. Rates of adverse events greatly varied between the disease types (0-280%, p<0.0001 and between the applied HIFU devices in both malignant (10.58-44.38%, p<0.0001 and benign lesions (1.67-17.57%, p<0.0001. Chronological analysis did not demonstrate a decrease in the rate of adverse events. Based upon evaluable adverse events, incidences in USgFU were consistent with those in MRgFU or transrectal HIFU. Some side effects frequently occurred following transrectal HIFU were not reported in USgFU. Several events including intrahepatic metastasis, intraoperative high fever, and occlusions of the superior mesenteric artery should be of particular concern because they have not been previously noted. The types of adverse events suggested that they were ultrasonic lesions. CONCLUSION: The frequency of adverse events depended on the location of the lesion and the type of HIFU device; however, side effects of USgFU were not yet understood. USgFU did not decrease the incidence of adverse events

  1. Optical focusing inside scattering media with time-reversed ultrasound microbubble encoded (TRUME) light

    CERN Document Server

    Ruan, Haowen; Yang, Changhuei

    2015-01-01

    Focusing light inside scattering media in a freely addressable fashion is challenging, as the wavefront of the scattered light is highly disordered. Recently developed ultrasound-guided wavefront shaping methods are addressing this challenge, albeit with relatively low modulation efficiency and resolution limitations. In this paper, we present a new technique, time-reversed ultrasound microbubble encoded (TRUME) optical focusing, which is able to focus light with improved efficiency and sub-ultrasound wavelength resolution. This method ultrasonically destructs microbubbles, and measures the wavefront change to compute and render a suitable time-reversed wavefront solution for focusing. We demonstrate that the TRUME technique can create an optical focus at the site of bubble destruction with a size of ~2 microns. Due to the nonlinear pressure-to-destruction response, the TRUME technique can break the addressable focus resolution barrier imposed by the ultrasound focus. We experimentally demonstrate a 2-fold ad...

  2. Focusing of ion beam with limit emittance by accelerator tube of electrostatic accelerator

    International Nuclear Information System (INIS)

    Focusing of nonrelativistic ion beam with finite emittance by accelerator tube is considered. Analytical relation between positions of the entrance and exit crossovers as a function of the beam emittance and the accelerator tube parameters was obtained. The comparison of conditions providing crossover to crossover transformation and conditions of entrance crossover optical image forming was carried out. 10 refs.; 3 figs

  3. PULSED-FOCUSING RECIRCULATING LINACS FOR MUON ACCELERATION

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Rolland PAUL

    2014-12-31

    Since the muon has a short lifetime, fast acceleration is essential for high-energy applications such as muon colliders, Higgs factories, or neutrino factories. The best one can do is to make a linear accelerator with the highest possible accelerating gradient to make the accelerating time as short as possible. However, the cost of such a single linear accelerator is prohibitively large due to expensive power sources, cavities, tunnels, and related infrastructure. As was demonstrated in the Thomas Jefferson Accelerator Facility (Jefferson Lab) Continuous Electron Beam Accelerator Facility (CEBAF), an elegant solution to reduce cost is to use magnetic return arcs to recirculate the beam through the accelerating RF cavities many times, where they gain energy on each pass. In such a Recirculating Linear Accelerator (RLA), the magnetic focusing strength diminishes as the beam energy increases in a conventional linac that has constant strength quadrupoles. After some number of passes the focusing strength is insufficient to keep the beam from going unstable and being lost. In this project, the use of fast pulsed quadrupoles in the linac sections was considered for stronger focusing as a function of time to allow more successive passes of a muon beam in a recirculating linear accelerator. In one simulation, it was shown that the number of passes could be increased from 8 to 12 using pulsed magnet designs that have been developed and tested. This could reduce the cost of linac sections of a muon RLA by 8/12, where more improvement is still possible. The expense of a greater number of passes and corresponding number of return arcs was also addressed in this project by exploring the use of ramped or FFAG-style magnets in the return arcs. A better solution, invented in this project, is to use combined-function dipole-quadrupole magnets to simultaneously transport two beams of different energies through one magnet string to reduce costs of return arcs by almost a factor of

  4. PRESAGE® as a new calibration method for high intensity focused ultrasound therapy

    International Nuclear Information System (INIS)

    High Intensity Focused ultrasound (HIFU) is a non-invasive cancer therapy that makes use of the mainly thermal effects of ultrasound to destroy tissue. In order to achieve reliable treatment planning, it is necessary to characterise the ultrasound source (transducer) and to understand how the wave propagates in tissue and the energy deposition in the focal region. This novel exploratory study investigated how HIFU affects PRESAGE®, an optical phantom used for radiotherapy dosimetry, which is potentially a rapid method of calibrating the transducer. Samples, of two different formulations, were exposed to focused ultrasound and imaged using Optical Computed Tomography. First results showed that, PRESAGE® changes colour on ultrasound exposure (darker green regions were observed) with the alterations being related to the acoustic power and sample composition. Future work will involve quantification of these alterations and understanding how to relate them to the mechanisms of action of HIFU

  5. Histopathological changes associated with high intensity focused ultrasound (HIFU) treatment for localised adenocarcinoma of the prostate

    OpenAIRE

    van Leenders, G J L H; Beerlage, H; Ruijter, E.; de la Rosette, J J M C H; van de Kaa, C A

    2000-01-01

    Aims—Investigation of the histopathological changes in prostatectomy specimens of patients with prostate cancer after high intensity focused ultrasound (HIFU) and identification of immunohistochemical markers for tissue damage after HIFU treatment.

  6. Transcranial MR-guided High Intensity Focused Ultrasound for Non-Invasive Functional Neurosurgery

    Science.gov (United States)

    Werner, Beat; Morel, Anne; Zadicario, Eyal; Jeanmonod, Daniel; Martin, Ernst

    2010-03-01

    While the development of transcranial MR-guided High Intensity Focused Ultrasound has been driven mainly by applications for tumor ablation this new intervention method is also very attractive for functional neurosurgery due to its non-invasiveness, the absence of ionizing radiation and the closed-loop intervention control by MRI. Here we provide preliminary data to demonstrate the clinical feasibility, safety and precision of non-invasive functional neurosurgery by transcranial MR-guided High Intensity Focused Ultrasound.

  7. High-Intensity Focused Ultrasound (HIFU) in Localized Prostate Cancer Treatment

    OpenAIRE

    Alkhorayef, Mohammed; Mahmoud, Mustafa Z.; Alzimami, Khalid S.; Sulieman, Abdelmoneim; Fagiri, Maram A.

    2015-01-01

    Summary Background 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. Material/Meth...

  8. High intensity focused ultrasound (HIFU) as the alternative method of treatment of oncourological diseases

    OpenAIRE

    Blyumberg B.I.; Fomkin R.N.; Popkov V.M.

    2012-01-01

    Increasing interest devoted to technology of high intensity focused ultrasound (high-intensity focused ultrasound, HIFU), basically, is explained by a wide spectrum of potential fields of application at minimum invasiveness of the given method. In oncourology HIFU is applied in prostate and kidney cancer. In case of tumors of renal parenchyma the given technique is being clinically tested, while HIFU is currently used in the practice of European oncourologists in treatment of prostate cancer....

  9. Transcranial magnetic resonance imaging-guided focused ultrasound: noninvasive central lateral thalamotomy for chronic neuropathic pain

    OpenAIRE

    Jeanmonod, D.; Werner, B.; Morel, A.; Michels, L; Zadicario, E; Schiff, G.; Martin, E.

    2012-01-01

    Object Recent technological developments open the field of therapeutic application of focused ultrasound to the brain through the intact cranium. The goal of this study was to apply the new transcranial magnetic resonance imaging-guided focused ultrasound (tcMRgFUS) technology to perform noninvasive central lateral thalamotomies (CLTs) as a treatment for chronic neuropathic pain. Methods In 12 patients suffering from chronic therapy-resistant neuropathic pain, tcMRgFUS CLT was propos...

  10. 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.

  11. Electron Beam Focusing in the Linear Accelerator (linac)

    Science.gov (United States)

    Jauregui, Luis

    2015-10-01

    To produce consistent data with an electron accelerator, it is critical to have a well-focused beam. To keep the beam focused, quadrupoles (quads) are employed. Quads are magnets, which focus the beam in one direction (x or y) and defocus in the other. When two or more quads are used in series, a net focusing effect is achieved in both vertical and horizontal directions. At start up there is a 5% calibration error in the linac at Thomas Jefferson National Accelerator Facility. This means that the momentum of particles passing through the quads isn't always what is expected, which affects the focusing of the beam. The objective is to find exactly how sensitive the focusing in the linac is to this 5% error. A linac was simulated, which contained 290 RF Cavities with random electric fields (to simulate the 5% calibration error), and a total momentum kick of 1090 MeV. National Science Foundation, Department of Energy, Jefferson Lab, Old Dominion University.

  12. Full-wave nonlinear ultrasound simulation on distributed clusters with applications in high-intensity focused ultrasound

    CERN Document Server

    Jaros, Jiri; Treeby, Bradley E

    2014-01-01

    Model-based treatment planning and exposimetry for high-intensity focused ultrasound (HIFU) requires the numerical simulation of nonlinear ultrasound propagation through heterogeneous and absorbing media. This is a computationally demanding problem due to the large distances travelled by the ultrasound waves relative to the wavelength of the highest frequency harmonic. Here, the k-space pseudospectral method is used to solve a set of coupled partial differential equations equivalent to a generalised Westervelt equation. The model is implemented in C++ and parallelised using the message passing interface (MPI) for solving large-scale problems on distributed clusters. The domain is partitioned using a 1D slab decomposition, and global communication is performed using a sparse communication pattern. Operations in the spatial frequency domain are performed in transposed space to reduce the communication burden imposed by the 3D fast Fourier transform. The performance of the model is evaluated using grid sizes up ...

  13. High-intensity focused ultrasound ablation for treatment of hepatocellular carcinoma and hypersplenism: preliminary study.

    Science.gov (United States)

    Zhu, Jing; Zhu, Hui; Mei, Zhechuan; Jin, Chengbing; Ran, Lifeng; Zhou, Kun; Yang, Wei; Zhang, Lian; She, Chaokun

    2013-10-01

    The purpose of this work was to preliminarily investigate the efficacy and safety of high-intensity focused ultrasound treatment of hepatocellular carcinoma and hypersplenism. Nine patients with hepatocellular carcinoma complicated by hypersplenism (5 male and 4 female; median age, 56 years; range, 51-66 years) were treated with ultrasound-guided high-intensity focused ultrasound. Complications were recorded. Laboratory examination and magnetic resonance imaging were used to evaluate the efficacy. After high-intensity focused ultrasound treatment, mean spleen ablation ± SD of 28.76% ± 6.1% was discovered; meanwhile, the white blood cell count, platelet count, and liver function of the patients were substantially improved during the follow-up period. In addition, symptoms such as epistaxis and gingival bleeding were ameliorated or even eliminated, and the quality of life was improved. Follow-up imaging showed a nonperfused volume in the spleen and an absence of a tumor blood supply at the treated lesions in the liver. For the first time to our knowledge, high-intensity focused ultrasound ablation was used to treat hepatocellular carcinoma complicated by hypersplenism. High-intensity focused ultrasound may be an effective and safe alternative for treatment of hepatocellular carcinoma complicated by hypersplenism, but further studies are necessary to clarify the mechanisms. PMID:24065267

  14. A new sensitizer DVDMS combined with multiple focused ultrasound treatments: an effective antitumor strategy

    Science.gov (United States)

    Xiong, Wenli; Wang, Pan; Hu, Jianmin; Jia, Yali; Wu, Lijie; Chen, Xiyang; Liu, Quanhong; Wang, Xiaobing

    2015-12-01

    Sonodynamic therapy (SDT) was developed as a promising noninvasive approach. The present study investigated the antitumor effect of a new sensitizer (sinoporphyrin sodium, referred to as DVDMS) combined with multiple ultrasound treatments on sarcoma 180 both in vitro and in vivo. The combined treatment significantly suppressed cell viability, potentiated apoptosis, and markedly inhibited angiogenesis in vivo. In vivo, the tumor weight inhibition ratio reached 89.82% fifteen days after three sonication treatments plus DVDMS. This effect was stronger than one ultrasound alone (32.56%) and than one round of sonication plus DVDMS (59.33%). DVDMS combined with multiple focused ultrasound treatments initiated tumor tissue destruction, induced cancer cell apoptosis, inhibited tumor angiogenesis, suppressed cancer cell proliferation, and decreased VEGF and PCNA expression levels. Moreover, the treatment did not show obvious signs of side effects or induce a drop in body weight. These results indicated that DVDMS combined with multiple focused ultrasounds may be a promising strategy against solid tumor.

  15. Study of focusing characteristics of ultrasound for designing acoustic lens in ultrasonic moxibustion device

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Hyun; Song, Sung Jin; Kim, Hak Joon [School of Mechanical Engineering, Sungkyunkwan University, Suwon (Korea, Republic of); Kim, Ki Bok [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2015-04-15

    Traditional moxibustion therapy can cause severe pain and leave scarring burns at the moxibustion site as it relies on the practitioner's subjective and qualitative treatment. Recently, ultrasound therapy has received attention as an alternative to moxibustion therapy owing to its objectiveness and quantitative nature. However, in order to convert ultrasound energy into heat energy, there is a need to precisely understand the ultrasound-focusing characteristics of the acoustic lens. Therefore, in this study, an FEM simulation was performed for acoustic lenses with different geometries a concave lens and zone lens as the geometry critically influences ultrasound focusing. The acoustic pressure field, amplitude, and focal point were also calculated. Furthermore, the performance of the fabricated acoustic lens was verified by a sound pressure measurement experiment.

  16. Sub-array patterns of spherical-section phased array for high intensity focused ultrasound surgery

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaodong; WANG Xufei; LU Mingzhu; WAN Mingxi

    2005-01-01

    The sub-array field patterns of spherical-section phased array were implemented for noninvasive ultrasound surgery of liver-tumor. The sub-array approach included field calculation, pseudo-inverse method and genetic algorithm. The sub-arrays uncovered by ribs according to scanned images normally emitted ultrasound. The results from different sub-arrays demonstrated quite satisfied acoustic performances, which included qualified focus size and intensity level for ultrasound surgery with single-focus and multi-foci patterns. Moreover, the patterns could decrease power accumulation on the ribs, and avoid damaging normal tissues. Thus the sub-array method provides a promising tool for phased array ultrasound propagating through strong obstacles like human rib cage, and it may broaden the therapeutic area, make the surgery safer and more flexible.

  17. H-Mode Accelerating Structures with PMQ Beam Focusing

    CERN Document Server

    Kurennoy, Sergey S; O'Hara, James F; Olivas, Eric R; Wangler, Thomas P

    2011-01-01

    We have developed high-efficiency normal-conducting RF accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of inter-digital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3-D modeling - electromagnetic computations, multi-particle beam-dynamics simulations with high currents, and thermal-stress analysis - for an IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or ...

  18. 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.

  19. Adapting MRI Acoustic Radiation Force Imaging For In Vivo Human Brain Focused Ultrasound Applications

    OpenAIRE

    Kaye, Elena A.; Pauly, Kim Butts

    2012-01-01

    A variety of MRI acoustic radiation force imaging (MR-ARFI) pulse sequences as the means for image guidance of focused ultrasound therapy have been recently developed and tested ex vivo and in animal models. To successfully translate MR-ARFI guidance into human applications, ensuring that MR-ARFI provides satisfactory image quality in the presence of patient motion and deposits safe amount of ultrasound energy during image acquisition is necessary. The first aim of this work was to study the ...

  20. High-Intensity Focused Ultrasound as Salvage Therapy for Patients With Recurrent Prostate Cancer After Radiotherapy

    OpenAIRE

    Song, Wan; Jung, U Seok; Suh, Yoon Seok; Jang, Hyun Jun; Sung, Hyun Hwan; Jeon, Hwang Gyun; Jeong, Byung Chang; Seo, Seong Il; Jeon, Seong Soo; Choi, Han Yong; Lee, Hyun Moo

    2014-01-01

    Purpose To evaluate the oncologic outcomes and postoperative complications of high-intensity focused ultrasound (HIFU) as a salvage therapy after external-beam radiotherapy (EBRT) failure in patients with prostate cancer. Materials and Methods Between February 2002 and August 2010, we retrospectively reviewed the medical records of all patients who underwent salvage HIFU for transrectal ultrasound-guided, biopsy-proven locally recurred prostate cancer after EBRT failure (by ASTRO definition: ...

  1. High intensity focused ultrasound vs. cryotherapy as primary treatment for prostate cancer

    OpenAIRE

    Ranjan, Pratyush; Saurabh, Gyan; Bansal, Rahul; Gupta, Amit

    2008-01-01

    Prostate cancer is one of the most commonly diagnosed cancers. Here, we will be discussing two upcoming techniques for its management. One is cryotherapy which has returned from oblivion after nearly 150 years armed with latest technology and looking as if its full potential has been recognized now. On the other hand is high intensity focused ultrasound (HIFU), the application of ultrasound to this field is relatively new and hence a lot of excitement and hope. We searched MEDLINE (PubMed 194...

  2. Compensating for bone interfaces and respiratory motion in high-intensity focused ultrasound.

    OpenAIRE

    Tanter, Mickaël; PERNOT, mathieu; Aubry, Jean-François; Montaldo, Gabriel; Marquet, Fabrice; Fink, Mathias

    2007-01-01

    Bursts of focused ultrasound energy a thousand times more intense than diagnostic ultrasound have become a non-invasive option for treating cancer, from breast to prostate or uterine fibroid, during the last decade. Despite this progress, many issues still need to be addressed. First, the distortions caused by defocusing obstacles, such as the skull or ribs, on the ultrasonic therapeutic beam are still being investigated. Multi-element transducer technology must be used in order to achieve su...

  3. 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 (psurvival between those who received stand-alone chemotherapy and those who did not receive any treatment (p>0.10). 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.

  4. Magnetic resonance image-guided versus ultrasound-guided high-intensity focused ultrasound in the treatment of breast cancer

    OpenAIRE

    Pei-Hong Wu; Sheng Li

    2013-01-01

    Image-guided high-intensity focused ultrasound (HIFU) has been used for more than ten years, primarily in the treatment of liver and prostate cancers. HIFU has the advantages of precise cancer ablation and excellent protection of healthy tissue. Breast cancer is a common cancer in women. HIFU therapy, in combination with other therapies, has the potential to improve both oncologic and cosmetic outcomes for breast cancer patients by providing a curative therapy that conserves mammary shape. Cu...

  5. H-Mode Accelerating Structures with PMQ Beam Focusing

    OpenAIRE

    Kurennoy, Sergey S.; Rybarcyk, Lawrence J.; O'Hara, James F.; Olivas, Eric R.; Wangler, Thomas P.

    2011-01-01

    We have developed high-efficiency normal-conducting RF accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of inter-digital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3-D modeling - electromagnetic c...

  6. 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

  7. High intensity focused ultrasound responsive metallo-supramolecular block copolymer micelles.

    Science.gov (United States)

    Liang, Bo; Tong, Rui; Wang, Zhenhua; Guo, Shengwei; Xia, Hesheng

    2014-08-12

    The metal-supramolecular diblock copolymer containing mechano-labile bis(terpyridine)-Cu(II) complex linkage in the junction point was synthesized. These metal-ligand containing amphiphilic copolymers are able to self-assemble in aqueous solution to form spherical micelles with poly(propylene glycol) block forming the hydrophobic core. It is found that high intensity focused ultrasound can open the copolymer micelles and trigger the release of the payload in the micelle. The micellar properties and release kinetics of encapsulated guest molecule in response to ultrasound stimuli were investigated. The weak Cu(II)-terpyridine dynamic bond in the copolymer chain can be cleaved under ultrasound and thus leads to the disruption of the copolymer micelle and the release of loaded cargo. This study will open up a new way for the molecular design of ultrasound modulated drug delivery systems. PMID:25072274

  8. Distribution of temperature elevation caused by moving high-intensity focused ultrasound transducer

    Science.gov (United States)

    Kim, Jungsoon; Jung, Jihee; Kim, Moojoon; Ha, Kanglyeol; Lee, Eunghwa; Lee, Ilkwon

    2015-07-01

    Ultrasonic thermal treatment for dermatology has been developed using a small high-intensity focused ultrasound (HIFU) transducer. The transducer moves horizontally at a constant while it emits focused ultrasound because the treatment needs a high-temperature area in skin tissue over a wide range of depths. In this paper, a tissue-mimicking phantom made of carrageenan and a thermochromic film were adopted to examine the temperature distribution in the phantom noninvasively when the focused ultrasound was irradiated from the moving transducer. The dependence of the high-temperature area on the irradiated acoustic energy and on the movement interval of the HIFU was analyzed experimentally. The results will be useful in ensuring safety and estimating the remedial value of the treatment.

  9. Early Clinical Experience Using High Intensity Focused Ultrasound for Palliation of Inoperable Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Liu Lin Xiong

    2009-03-01

    Full Text Available Objective To evaluate the safety and efficacy of high intensity focused ultrasound for palliation of inoperable pancreatic cancer in humans. Patients Eighty-nine patients with advanced pancreatic cancer were treated with high intensity focused ultrasound. There were 4 patients with stage II, 39 patients with stage III, and 46 patients with stage IV disease. The location of the tumors was as follows: head of pancreas 34 patients, body and/or tail of pancreas 55 patients. Methods Pain relief, local tumor control rate, median survival and complications were observed after high intensity focused ultrasound treatment. Results In the clinical treatments in humans the following local tumor control was seen: complete response, 0%; partial response, 14.6%; no change, 57.3%; progressive disease, 28.1%. Pain relief was achieved in 80.6% of patients who had pain prior to high intensity focused ultrasound therapy. The median survival was 26.0 months for patients with stage II disease, 11.2 months for patients with stage III disease, and 5.4 months for patients with stage IV disease. One-year survival rate was as follows: stage II, 100%; stage III, 41.0%; and stage IV, 6.5%. Twoyear survival rate was as follows: stage II, 75.0%; stage III, 10.3%; and stage IV, 0%. Complications included superficial skin burns (3.4%, subcutaneous fat sclerosis (6.7%, and an asymptomatic pancreatic pseudocyst (1.1%. There were no severe complications or adverse events related to high intensity focused ultrasound therapy seen in any of the patients treated. Conclusions Although this retrospective study has significant limitations, preliminary results suggest that the clinical application of high intensity focused ultrasound for pancreatic cancer appears to be safe and is a promising modality of treatment for palliation of pain related to pancreatic cancer.

  10. Editorial: Focus on Laser- and Beam-Driven Plasma Accelerators

    Science.gov (United States)

    Joshi, Chan; Malka, Victor

    2010-04-01

    The ability of short but intense laser pulses to generate high-energy electrons and ions from gaseous and solid targets has been well known since the early days of the laser fusion program. However, during the past decade there has been an explosion of experimental and theoretical activity in this area of laser-matter interaction, driven by the prospect of realizing table-top plasma accelerators for research, medical and industrial uses, and also relatively small and inexpensive plasma accelerators for high-energy physics at the frontier of particle physics. In this focus issue on laser- and beam-driven plasma accelerators, the latest advances in this field are described. Focus on Laser- and Beam-Driven Plasma Accelerators Contents Slow wave plasma structures for direct electron acceleration B D Layer, J P Palastro, A G York, T M Antonsen and H M Milchberg Cold injection for electron wakefield acceleration X Davoine, A Beck, A Lifschitz, V Malka and E Lefebvre Enhanced proton flux in the MeV range by defocused laser irradiation J S Green, D C Carroll, C Brenner, B Dromey, P S Foster, S Kar, Y T Li, K Markey, P McKenna, D Neely, A P L Robinson, M J V Streeter, M Tolley, C-G Wahlström, M H Xu and M Zepf Dose-dependent biological damage of tumour cells by laser-accelerated proton beams S D Kraft, C Richter, K Zeil, M Baumann, E Beyreuther, S Bock, M Bussmann, T E Cowan, Y Dammene, W Enghardt, U Helbig, L Karsch, T Kluge, L Laschinsky, E Lessmann, J Metzkes, D Naumburger, R Sauerbrey, M. Scḧrer, M Sobiella, J Woithe, U Schramm and J Pawelke The optimum plasma density for plasma wakefield excitation in the blowout regime W Lu, W An, M Zhou, C Joshi, C Huang and W B Mori Plasma wakefield acceleration experiments at FACET M J Hogan, T O Raubenheimer, A Seryi, P Muggli, T Katsouleas, C Huang, W Lu, W An, K A Marsh, W B Mori, C E Clayton and C Joshi Electron trapping and acceleration on a downward density ramp: a two-stage approach R M G M Trines, R Bingham, Z Najmudin

  11. Processing ultrasound backscatter to monitor high-intensity focused ultrasound (HIFU) therapy

    Science.gov (United States)

    Kaczkowski, Peter J.; Anand, Ajay; Bailey, Michael R.

    2005-09-01

    The development of new noninvasive surgical methods such as HIFU for the treatment of cancer and internal bleeding requires simultaneous development of new sensing approaches to guide, monitor, and assess the therapy. Ultrasound imaging using echo amplitude has long been used to map tissue morphology for diagnostic interpretation by the clinician. New quantitative ultrasonic methods that rely on amplitude and phase processing for tissue characterization are being developed for monitoring of ablative therapy. We have been developing the use of full wave ultrasound backscattering for real-time temperature estimation, and to image changes in tissue backscatter spectrum as therapy progresses. Both approaches rely on differential processing of the backscatter signal in time, and precise measurement of phase differences. Noise and artifacts from motion and nonstationary speckle statistics are addressed by constraining inversions for tissue parameters with physical models. We present results of HIFU experiments with static point and scanned HIFU exposures in which temperature rise can be accurately mapped using a new heat transfer equation (HTE) model-constrained inverse approach. We also present results of a recently developed spectral imaging method that elucidates microbubble-mediated nonlinearity not visible as a change in backscatter amplitude. [Work supported by Army MRMC.

  12. Stimulated acceleration and confinement of deuterons in focused discharges

    International Nuclear Information System (INIS)

    The energy spectrum of accelerated D/sup +/ ions with energy 0.1 MeV ≤ E ≤ 7 MeV has been experimentally determined for the confined ions in a plasma focus pinch via the D-D neutron spectrum and for the ejected ions via a variety of ion spectrometers, with or without nanosec time resolution. A strong correlation exists between (i) neutron yield y/sub n/ in a single shot and (ii) escaping ion-beam fluence d/sup 2/phi/dω dE which increases with y/sub n/ as long as y/sub n/ ≤ 2 y, where y-bar/sub n/ is the mean value of y/sub n/ over hundreds of shots with the same filling pressure, capacitor-bank voltage, electrode geometry. In shots with y/sub n/ > 3 y-bar/sub n/ the ion emission falls below the limit of detectability. This is verified by observations of the ion emission in all directions. The insertion of field distortion elements between the electrodes increases y-bar/sub n/ by a factor > 3 without affecting the correlation between ion fluence and y/sub n/ (y-bar/sub n/ > 10/sup 9/ for 6 kJ at 16 kV shots in 6 Torr of D/sub 2/; y/sub n/ > 6 x 10/sup 8/ at 3 Torr). The distribution of the current in the interelectrode plasma region and the induced variations via field distortion elements are monitored by magnetic probes. The magnitude of the observed current-intensity peaks controls ion-accelerated fields and ion confining fields. The characteristics of the confined population of accelerated ions and those of the ejected ions are consistent with an acceleration mechanism which is extremely localized in space (< 100 μm). In parallel with spectrometer data nuclear activation of gaseous target and of solid targets is used as further method for discriminating among different processes of ion acceleration

  13. Acute Cholecystitis Detected by Serial Emergency Department Focused Right Upper Quadrant Ultrasound

    Directory of Open Access Journals (Sweden)

    David Bosch

    2016-06-01

    Full Text Available Acute cholecystitis is a common etiology of acute right upper quadrant pain in patients presenting to the emergency department (ED. The use of ED-focused right upper quadrant ultrasound (RUQ US is becoming more widely utilized to evaluate abdominal pain thought to be hepatobiliary in nature. We describe a case series of two patients with acute cholecystitis detected by serial ED-focused RUQ US. Case 1: A woman presented to the ED with epigastric pain of acute onset. She was initially found to have a mild leukocytosis and cholelithiasis detected by ED-focused RUQ US. Seventy-five minutes later, the patient had a repeat bedside ultrasound by the same sonographer that showed visual evidence of acute cholecystitis that was later confirmed by surgical pathology. She was treated operatively. Case 2: A man with known cholelithiasis presents to the ED with acute-onset RUQ pain. Initial RUQ ultrasound performed by the Department of Radiology (University of Colorado Hospital was equivocal, showing cholelithiasis with a mildly thickened wall and no pericholecystic fluid. A repeat ED-focused RUQ ultrasound 5 hours later showed increased wall thickness and pericholecystic fluid. The patient was subsequently taken for same-day cholecystectomy. This case series demonstrates the dynamic and progressive nature of acute cholecystitis detected by ED-focused RUQ US. It also highlights how serial bedside ultrasonography can reduce harm, appropriately triage patients with hepatobiliary disease and lead to reductions in overall morbidity.

  14. Targeted Drug Delivery to the Brain by MRI-guided Focused Ultrasound

    Science.gov (United States)

    Treat, Lisa Hsu; McDannold, Nathan; Vykhodtseva, Natalia; Zhang, Yongzhi; Tam, Karen; Hynynen, Kullervo

    2006-05-01

    The effect of focused ultrasound on the absorption of liposome-encapsulated doxorubicin in the brain was investigated. By applying focused ultrasound in the presence of microbubble ultrasound contrast agent, we achieved targeted drug delivery to the brain in vivo. Tissue drug concentrations in sonicated brain corresponded with cytotoxic levels measured in various human tumors and were significantly different from those measured in unexposed contralateral control samples (p ⩽ 0.02). In addition, increased MR signal enhancement at the focal location on contrast-enhanced T1-weighted fast spin echo images correlated with increased penetration of doxorubicin into brain tissue (r = 0.85), indicating the potential of MRI to be used as an indicator of blood-brain barrier permeability during treatment. Further investigation is required to evaluate the efficacy of this technique and to optimize its parameters for clinical application.

  15. Clinical Application of High-intensity Focused Ultrasound in Cancer Therapy.

    Science.gov (United States)

    Hsiao, Yi-Hsuan; Kuo, Shou-Jen; Tsai, Horng-Der; Chou, Ming-Chih; Yeh, Guang-Perng

    2016-01-01

    The treatment of cancer is an important issue in both developing and developed countries. Clinical use of ultrasound in cancer is not only for the diagnosis but also for the treatment. Focused ultrasound surgery (FUS) is a noninvasive technique. By using the combination of high-intensity focused ultrasound (HIFU) and imaging method, FUS has the potential to ablate tumor lesions precisely. The main mechanisms of HIFU ablation involve mechanical and thermal effects. Recent advances in HIFU have increased its popularity. Some promising results were achieved in managing various malignancies, including pancreas, prostate, liver, kidney, breast and bone. Other applications include brain tumor ablation and disruption of the blood-brain barrier. We aim at briefly outlining the clinical utility of FUS as a noninvasive technique for a variety of types of cancer treatment. PMID:26918034

  16. Photoacoustic-guided focused ultrasound (PAFUSion for identifying reflection artifacts in photoacoustic imaging

    Directory of Open Access Journals (Sweden)

    Mithun Kuniyil Ajith Singh

    2015-12-01

    Full Text Available Influence of acoustic inhomogeneities and resulting reflection artifacts is an important problem in reflection-mode photoacoustic imaging. Absorption of light by skin and superficial optical absorbers will generate photoacoustic transients, which traverse into the tissue and get reflected from structures having different acoustic impedance. These reflected photoacoustic signals, when reconstructed, may appear in the region of interest, which causes difficulties in image interpretation. We propose a novel method to identify and potentially eliminate reflection artifacts in photoacoustic images using photoacoustic-guided focused ultrasound [PAFUSion]. Our method uses focused ultrasound pulses to mimic the wave field produced by photoacoustic sources and thus provides a way to identify reflection artifacts in clinical combined photoacoustic and pulse-echo ultrasound. Simulation and phantom results are presented to demonstrate the validity and impact of this method. Results show that PAFUSion can identify reflections in photoacoustic images and thus envisages potential for improving photoacoustic imaging of acoustically inhomogeneous tissue.

  17. Tuning the DARHT Axis-II linear induction accelerator focusing

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Carl A. [Los Alamos National Laboratory

    2012-04-24

    Flash radiography of large hydrodynamic experiments driven by high explosives is a well-known diagnostic technique in use at many laboratories, and the Dual-Axis Radiography for Hydrodynamic Testing (DARHT) facility at Los Alamos produces flash radiographs of large hydrodynamic experiments. Two linear induction accelerators (LIAs) make the bremsstrahlung radiographic source spots for orthogonal views of each test. The 2-kA, 20-MeV Axis-I LIA creates a single 60-ns radiography pulse. The 1.7-kA, 16.5-MeV Axis-II LIA creates up to four radiography pulses by kicking them out of a longer pulse that has a 1.6-{mu}s flattop. The Axis-II injector, LIA, kicker, and downstream transport (DST) to the bremsstrahlung converter are described. Adjusting the magnetic focusing and steering elements to optimize the electron-beam transport through an LIA is often called 'tuning.' As in all high-current LIAs, the focusing field is designed to be as close to that of the ideal continuous solenoid as physically possible. In ideal continuous solenoidal transport a smoothly varying beam size can easily be found for which radial forces balance, and the beam is said to be 'matched' to the focusing field. A 'mismatched' beam exhibits unwanted oscillations in size, which are a source of free energy that contributes to emittance growth. This is undesirable, because in the absence of beam-target effects, the radiographic spot size is proportional to the emittance. Tuning the Axis-II LIA is done in two steps. First, the solenoidal focusing elements are set to values designed to provide a matched beam with little or no envelope oscillations, and little or no beam-breakup (BBU) instability growth. Then, steering elements are adjusted to minimize the motion of the centroid of a well-centered beam at the LIA exit. This article only describes the design of the tune for the focusing solenoids. The DARHT Axis-II LIA was required to be re-tuned after installing an

  18. Numerical Study on Focusing of Ultrasounds in Microbubble-enhanced HIFU

    Science.gov (United States)

    Matsumoto, Yoichiro; Okita, Kohei; Takagi, Shu

    2011-11-01

    The injection of microbubbles into the target tissue enhances tissue heating in High-Intensity Focused Ultrasound therapy, via inertial cavitation. The control of the inertial cavitation is required to achieve the efficient tissue ablation. Microbubbles between a transducer and a target disturb the ultrasound propagation depending on the conditions. A method to clear such microbubbles has been proposed by Kajiyama et al. [Physics Procedia 3 (2010) 305-314]. In the method, the irradiation of intense ultrasounds with a burst waveform fragmentize microbubbles in the pathways before the irradiation of ultrasounds for tissue heating. The vitro experiment using a gel containing microbubbles has showed that the method enables to heat the target correctly by controlling the microbubble distribution. Following the experiment, we simulate the focusing of ultrasounds through a mixture containing microbubbles with considering the size and number density distributions in space. The numerical simulation shows that the movement of the heating region from the transducer side to the target by controlling the microbubble distributions. The numerical results elucidate well the experimental ones.

  19. Analytical estimation of ultrasound properties, thermal diffusivity, and perfusion using magnetic resonance-guided focused ultrasound temperature data

    Science.gov (United States)

    Dillon, C. R.; Borasi, G.; Payne, A.

    2016-01-01

    For thermal modeling to play a significant role in treatment planning, monitoring, and control of magnetic resonance-guided focused ultrasound (MRgFUS) thermal therapies, accurate knowledge of ultrasound and thermal properties is essential. This study develops a new analytical solution for the temperature change observed in MRgFUS which can be used with experimental MR temperature data to provide estimates of the ultrasound initial heating rate, Gaussian beam variance, tissue thermal diffusivity, and Pennes perfusion parameter. Simulations demonstrate that this technique provides accurate and robust property estimates that are independent of the beam size, thermal diffusivity, and perfusion levels in the presence of realistic MR noise. The technique is also demonstrated in vivo using MRgFUS heating data in rabbit back muscle. Errors in property estimates are kept less than 5% by applying a third order Taylor series approximation of the perfusion term and ensuring the ratio of the fitting time (the duration of experimental data utilized for optimization) to the perfusion time constant remains less than one.

  20. An ex vivo human lung model for ultrasound-guided high-intensity focused ultrasound therapy using lung flooding.

    Science.gov (United States)

    Wolfram, Frank; Reichenbach, Jürgen R; Lesser, Thomas G

    2014-03-01

    The usability of an ex vivo human lung model for ablation of lung cancer tissue with high-intensity focused ultrasound (HIFU) is described. Lung lobes were flooded with saline, with no gas remaining after complete atelectasis. The tumor was delineated sono-morphologically. Speed of sound, tissue density and ultrasound attenuation were measured for flooded lung and different pulmonary cancer tissues. The acoustic impedance of lung cancer tissue (1.6-1.9 mega-Rayleighs) was higher than that of water, as was its attenuation coefficient (0.31-0.44 dB/cm/MHz) compared with that of the flooded lung (0.12 dB/cm/MHz). After application of HIFU, the temperature in centrally located lung cancer surrounded by the flooded lung increased as high as 80°C, which is sufficient for treatment. On the basis of these preliminary results, ultrasound-guided HIFU ablation of lung cancer, by lung flooding with saline, appears feasible and should be explored in future clinical studies. PMID:24412177

  1. Analytical estimation of ultrasound properties, thermal diffusivity, and perfusion using magnetic resonance-guided focused ultrasound temperature data.

    Science.gov (United States)

    Dillon, C R; Borasi, G; Payne, A

    2016-01-21

    For thermal modeling to play a significant role in treatment planning, monitoring, and control of magnetic resonance-guided focused ultrasound (MRgFUS) thermal therapies, accurate knowledge of ultrasound and thermal properties is essential. This study develops a new analytical solution for the temperature change observed in MRgFUS which can be used with experimental MR temperature data to provide estimates of the ultrasound initial heating rate, Gaussian beam variance, tissue thermal diffusivity, and Pennes perfusion parameter. Simulations demonstrate that this technique provides accurate and robust property estimates that are independent of the beam size, thermal diffusivity, and perfusion levels in the presence of realistic MR noise. The technique is also demonstrated in vivo using MRgFUS heating data in rabbit back muscle. Errors in property estimates are kept less than 5% by applying a third order Taylor series approximation of the perfusion term and ensuring the ratio of the fitting time (the duration of experimental data utilized for optimization) to the perfusion time constant remains less than one. PMID:26741344

  2. An image-guided high intensity focused ultrasound device for uterine fibroids treatment

    International Nuclear Information System (INIS)

    A high intensity focused ultrasound (HIFU) device was developed for treating uterine fibroid tumors. This prototype device enables image-guided therapy by aligning a commercially available abdominal ultrasound image probe to a vaginal HIFU transducer so the HIFU focus is in the image plane. The device was designed based on anatomical constraints of the female pelvic structures. HIFU was generated using a 3.5 MHz PZT-8 crystal, 25.4 mm in diameter, bonded to an aluminum lens. Computer simulations were performed to ensure that effective focusing was achievable at a fixed focal depth of 40 mm. Transducer efficiency was empirically determined to be 58%, and the half pressure maximum focal dimensions were 11 mm in length and 1.2 mm in width. A water-filled latex condom surrounding the transducer provided acoustic coupling, a stand-off, and allowed water circulation for transducer cooling. In vitro experiments in a tissue-mimicking gel phantom and in turkey breast demonstrated ultrasound image-guided lesion formation, or tissue necrosis, at the focus due to HIFU induced thermal and cavitation effects. The HIFU treatment site appeared as a hyperechoic spot on the ultrasound image at intensities above 1250 W/cm2. The results of in vitro experiments and in vivo ergonomic testing in six human volunteers indicated that the device has the potential of providing a nonsurgical approach for uterine fibroid treatment. Future in vivo studies in large animal models and fibroids patients are planned

  3. Systematic review of high-intensity focused ultrasound ablation in the treatment of breast cancer

    NARCIS (Netherlands)

    Peek, M.C.L.; Ahmed, M.; Napoli, A.; Haken, ten B.; McWilliams, S.; Usiskin, S.I.; Pinder, S.E.; Hemelrijck, Van M.; Douek, M.

    2015-01-01

    Background: A systematic review was undertaken to assess the clinical efficacy of non-invasive high-intensity focused ultrasound (HIFU) ablation in the treatment of breast cancer. Methods: MEDLINE/PubMed library databases were used to identify all studies published up to December 2013 that evaluate

  4. Bone metastasis treatment using magnetic resonance-guided high intensity focused ultrasound

    NARCIS (Netherlands)

    Yeo, Sin Yuin; Elevelt, Aaldert; Donato, Katia; van Rietbergen, Bert; ter Hoeve, Natalie D.; van Diest, Paul J.; Grüll, Holger

    2015-01-01

    Objectives: Bone pain resulting from cancer metastases reduces a patient's quality of life. Magnetic Resonance-guided High Intensity Focused Ultrasound (MR-HIFU) is a promising alternative palliative thermal treatment technique for bone metastases that has been tested in a few clinical studies. Here

  5. 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.

  6. Transrectal high-intensity focused ultrasound for the treatment of prostate cancer: Past, present, and future

    OpenAIRE

    Mearini, Luigi; Porena, Massimo

    2010-01-01

    Upon a review of recently published articles on high-intensity focused ultrasound (HIFU) in the treatment of prostate cancer, we evaluated the current status of HIFU as a primary treatment option for localized prostate cancer and its use as salvage therapy when radiation failed. We also briefly discuss current issues in indications, definition of response, and finally the future of HIFU development.

  7. Miniaturized Cell Lysis Device Using Spherically Focused Ultrasound

    Institute of Scientific and Technical Information of China (English)

    李刚; 肖宏; 郭旻; 程京

    2003-01-01

    A prototype of a miniaturized cell lysis device developed using a concave spherical transducer is capable of lysing bacteria without added chemical denaturants, enzymes or microparticles and is capable of efficiently lysing yeast without any mechanical or enzymatic pretreatment.The device is designed for miniature bio-analysis systems where cell lysing is needed to obtain intracellular materials for further analysis such as DNA identification.The device lysis efficiency was evaluated using viable cell counts and microscopy.Additionally, the device efficiency was compared with that of traditional chemical cell lysis methods using standard molecular biological techniques such as agarose gels and ultraviolet (UV) spectroscopy.The results indicate that efficient bacteria and cell disruption can be achieved through a low-voltage-driven and spherically focused high-frequency ultrasonic device.

  8. Ultrasound

    Science.gov (United States)

    Ultrasound is a type of imaging. It uses high-frequency sound waves to look at organs and ... liver, and other organs. During pregnancy, doctors use ultrasound to view the fetus. Unlike x-rays, ultrasound ...

  9. Enhancement of antitumor vaccine in ablated hepatocellular carcinoma by high-intensity focused ultrasound

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate whether tumor debris created by high-intensity focused ultrasound(HIFU)could trigger antitumor immunity in a mouse hepatocellular carcinoma model. METHODS:Twenty C57BL/6J mice bearing H22 hepatocellular carcinoma were used to generate antitumor vaccines.Ten mice underwent HIFU ablation,and the remaining 10 mice received a sham-HIFU procedure with no ultrasound irradiation.Sixty normal mice were randomly divided into HIFU vaccine,tumor vaccine and control groups.These mice were immunized w...

  10. The mechanism of lesion formation by focused ultrasound ablation catheter for treatment of atrial fibrillation

    Science.gov (United States)

    Sinelnikov, Y. D.; Fjield, T.; Sapozhnikov, O. A.

    2009-10-01

    The application of therapeutic ultrasound for the treatment of atrial fibrillation (AF) is investigated. The results of theoretical and experimental investigation of ultrasound ablation catheter are presented. The major components of the catheter are the high power cylindrical piezoelectric element and parabolic balloon reflector. Thermal elevation in the ostia of pulmonary veins is achieved by focusing the ultrasound beam in shape of a torus that transverses the myocardial tissue. High intensity ultrasound heating in the focal zone results in a lesion surrounding the pulmonary veins that creates an electrical conduction blocks and relief from AF symptoms. The success of the ablation procedure largely depends on the correct choice of reflector geometry and ultrasonic power. We present a theoretical model of the catheter’s acoustic field and bioheat transfer modeling of cardiac lesions. The application of an empirically derived relation between lesion formation and acoustic power is shown to correlate with the experimental data. Developed control methods combine the knowledge of theoretical acoustics and the thermal lesion formation simulations with experiment and thereby establish dosimetry that contributes to a safe and effective ultrasound ablation procedure.

  11. 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.

  12. High intensity focused ultrasound ablation: A new therapeutic option for solid tumors

    Directory of Open Access Journals (Sweden)

    Orsi Franco

    2010-01-01

    Full Text Available Surgery has been the standard of care in selected cases with solid tumors. However, a majority of patients are unable to undergo surgical resection because of the tumor sites, advanced stages, or poor general condition. High intensity focused ultrasound (HIFU is a novel non-invasive technique that is capable of producing coagulative necrosis at a precise focal point within the body, without harming overlying and adjacent structures even within the path of the beam. Diagnostic ultrasound was the first imaging modality used for guiding HIFU ablation in the 1990s. Over the last decade, thousands of patients with uterine fibroids, liver cancer, breast cancer, pancreatic cancer, bone tumors, renal cancer have been treated with ultrasound imaging-guided HIFU (USgHIFU worldwide. This USgHIFU system [Chongqing Haifu (HIFU Tech Co., Ltd., Chongqing, China] was first equipped in Asia, now in Europe. Several research groups have demonstrated that HIFU is safe and effective in treating human solid tumors. In 2004, the magnetic resonance guided focused ultrasound surgery (MRgFUS was approved by the United States Food and Drug Administration (FDA for clinical treatments of uterine fibroids. We conclude that HIFU offers patients another choice when no other treatment available or when patients refused surgical operation. This technique may play a key role in future clinical practice.

  13. Toward Deep Brain Monitoring with Superficial EEG Sensors Plus Neuromodulatory Focused Ultrasound.

    Science.gov (United States)

    Darvas, Felix; Mehić, Edin; Caler, Connor J; Ojemann, Jeff G; Mourad, Pierre D

    2016-08-01

    Noninvasive recordings of electrophysiological activity have limited anatomic specificity and depth. We hypothesized that spatially tagging a small volume of brain with a unique electroencephalography (EEG) signal induced by pulsed focused ultrasound could overcome those limitations. As a first step toward testing this hypothesis, we applied transcranial ultrasound (2 MHz, 200-ms pulses applied at 1050 Hz for 1 s at a spatial peak temporal average intensity of 1.4 W/cm(2)) to the brains of anesthetized rats while simultaneously recording EEG signals. We observed a significant 1050-Hz electrophysiological signal only when ultrasound was applied to a living brain. Moreover, amplitude demodulation of the EEG signal at 1050 Hz yielded measurement of gamma band (>30 Hz) brain activity consistent with direct measurements of that activity. These results represent preliminary support for use of pulsed focused ultrasound as a spatial tagging mechanism for non-invasive EEG-based mapping of deep brain activity with high spatial resolution. PMID:27181686

  14. Dual-focus therapeutic ultrasound transducer for production of broad tissue lesions.

    Science.gov (United States)

    Jeong, Jong Seob; Cannata, Jonathan M; Shung, K Kirk

    2010-11-01

    In noninvasive high-intensity focused ultrasound (HIFU) treatment, formation of a large tissue lesion per sonication is desirable for reducing the overall treatment time. The goal of this study is to show the feasibility of enlarging tissue lesion size with a dual-focus therapeutic ultrasound transducer (DFTUT) by increasing the depth-of-focus (DOF). The proposed transducer consists of a disc- and an annular-type element of different radii of curvatures to produce two focal zones. To increase focal depth and to maintain uniform beamwidth of the elongated DOF, each element transmits ultrasound of a different center frequency: the inner element at a higher frequency for near field focusing and the outer element at a lower frequency for far field focusing. By activating two elements at the same time with a single transmitter capable of generating a dual-frequency mixed signal, the overall DOF of the proposed transducer may be extended considerably. A prototype transducer composed of a 4.1 MHz inner element and a 2.7 MHz outer element was fabricated to obtain preliminary experimental results. The feasibility the proposed technique was demonstrated through sound field, temperature and thermal dose simulations. The performance of the prototype transducer was verified by hydrophone measurements and tissue ablation experiments on a beef liver specimen. When several factors affecting the length and the uniformity of elongated DOF of the DFTUT are optimized, the proposed therapeutic ultrasound transducer design may increase the size of ablated tissues in the axial direction and, thus, decreasing the treatment time for a large volume of malignant tissues especially deep-seated targets. PMID:20870346

  15. A numerical study of transcranial focused ultrasound beam propagation at low frequency

    International Nuclear Information System (INIS)

    The feasibility of transcranial ultrasound focusing with a non-moving phased array and without skull-specific aberration correction was investigated using computer simulations. Three cadaver skull CT image data sets were incorporated into an acoustic wave transmission model to simulate transskull ultrasound wave propagation. Using a 0.25 MHz hemispherical array (125 mm radius of curvature, 250 mm diameter, 24 255 elements), the simulated beams could be focused and steered with transducer element driving phases and amplitude adjusted for focal beam steering in water (water-path). A total of 82 foci, spanning wide ranges of distance in the three orthogonal dimensions, were simulated to test the focal beam steering capability inside the three skulls. The acoustic pressure distribution in a volume of 20 x 20 x 20 mm3 centred at each focus was calculated with a 0.5 mm spacing in each axis. Clearly defined foci were retained through the skulls (skull-path) in most cases. The skull-path foci were on average 1.6 ± 0.8 mm shifted from their intended locations. The -3 dB skull-path beam width and length were on average 4.3 ± 1.0 mm and 7.7 ± 1.8 mm, respectively. The skull-path sidelobe levels ranged from 25% to 55% of the peak pressure values. The skull-path peak pressure levels were about 10%-40% of their water-path counterparts. Focusing low-frequency beam through skull without skull-specific aberration correction is possible. This method may be useful for applying ultrasound to disrupt the blood-brain barrier for targeted delivery of therapeutic or diagnostic agents, or to induce microbubbles, or for other uses of ultrasound in brain where the required power levels are low and the sharp focusing is not needed

  16. 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.

  17. A collimated focused ultrasound beam of high acoustic transmission and minimum diffraction achieved by using a lens with subwavelength structures

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Zhou; Tu, Juan; Cheng, Jianchun [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Guo, Xiasheng, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Wu, Junru [Department of Physics, University of Vermont, Burlington, Vermont 05405 (United States); Huang, Pingtong [Department of Ultrasound, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009 (China); Zhang, Dong, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080 (China)

    2015-09-14

    An acoustic focusing lens incorporated with periodically aligned subwavelength grooves corrugated on its spherical surface has been developed. It is demonstrated theoretically and experimentally that acoustic focusing achieved by using the lens can suppress the relative side-lobe amplitudes, enhance the focal gain, and minimize the shifting of the focus. Use of the lens coupled with a planar ultrasound transducer can generate an ultrasound beam with enhanced acoustic transmission and collimation effect, which offers the capability of improving the safety, efficiency, and accuracy of targeted surgery implemented by high intensity focused ultrasound.

  18. 3-point support mechanical steering system for high intensity focused ultrasound

    International Nuclear Information System (INIS)

    We have developed a simple approach for mechanically scanning a focused bowl ultrasound (US) transducer for either hyperthermia or tissue ablation therapies called the 3-point support (3PS) mechanical steering technique. The scanning involves translation of the required 3D motion of the ultrasound transducer to the more manageable linear movement of three support rods. It is a cost-effective alternative, especially compared with electronic scanning and other previous implementations of mechanically scanned systems. The 3PS approach is particularly well suited for integration with our microwave breast imaging technique-the combination of which could be an effective, low-cost thermal therapy/monitoring approach. The results show that the US focus can be moved laterally in a spiral pattern 3 cm below the surface in a gel phantom and that similar patterns can be moved to multiple locations within the phantom volume in succession. The feasibility of simultaneously acquiring microwave thermal images is also demonstrated

  19. Three-Dimensional Quantitative Optical Measurement of Asymmetrically Focused Ultrasound Pressure Field

    Science.gov (United States)

    Shimazaki, Yuta; Harigane, Soichiro; Yoshizawa, Shin; Umemura, Shin-ichiro

    2012-07-01

    High-intensity focused ultrasound (HIFU) is used for the treatment of tumors such as prostate cancer. In the development of this technique, an accurate and fast measurement of the HIFU pressure field is important. A hydrophone is generally used for the measurement, but it might disturb the pressure field and scanning it in the field takes a long time. On the other hand, optical ultrasonic field mapping has the advantages of speed and its nature of not by interfering with the acoustic field. In this study, we reconstructed an asymmetric ultrasound field by optical measurement using a computed tomography (CT) algorithm. The asymmetric field was generated by a focused transducer with four elements. Also, the absolute measurement of ultrasonic pressure was checked by measuring the center of the field of the charge-coupled device (CCD) camera. The results showed overall agreement with those of hydrophone measurement.

  20. High intensity focused ultrasound (HIFU as the alternative method of treatment of oncourological diseases

    Directory of Open Access Journals (Sweden)

    Blyumberg B.I.

    2012-12-01

    Full Text Available Increasing interest devoted to technology of high intensity focused ultrasound (high-intensity focused ultrasound, HIFU, basically, is explained by a wide spectrum of potential fields of application at minimum invasiveness of the given method. In oncourology HIFU is applied in prostate and kidney cancer. In case of tumors of renal parenchyma the given technique is being clinically tested, while HIFU is currently used in the practice of European oncourologists in treatment of prostate cancer. The majority of the references describing the results of HIFU application in prostate cancer is based on data of a number of clinical observations. It has been proved that HIFU is a possible method of treatment of highly — and moderate-differentiated tumors, and local relapses after remote radial therapy.

  1. 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.

  2. 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

    2015-01-01

    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. PMID:26556647

  3. Uterine artery embolisation and magnetic resonance guided focused ultrasound treatment of uterine fibroids

    International Nuclear Information System (INIS)

    Uterine fibroids are the most common benign female tumours during reproductive age. The traditional treatment for this condition is typically hysterectomy. However, there are new technologies on the rise, such as Uterine Artery Embolisation and Magnetic Resonance-guided Focused Ultrasound which are directed towards a minimally invasive or even noninvasive treatment of uterine fibroids. These modern procedures allow for a fast recovery and preservation of fertility. In this work, we presented these alternative procedures and highlighted their and limitations. (authors)

  4. Uterine artery embolisation and magnetic resonance-guided focused ultrasound treatment of uterine fibroids

    International Nuclear Information System (INIS)

    Uterine fibroids are the most common benign female tumours during reproductive age. The traditional treatment for this condition is typically hysterectomy. However, there are new technologies on the rise, such as Uterine Artery Embolisation and Magnetic Resonance-guided Focused Ultrasound which are directed towards a minimally invasive or even noninvasive treatment of uterine fibroids. These modern procedures allow for a fast recovery and preservation of fertility. In this work, we presented these alternative procedures and highlighted their advantages and limitations

  5. Image-Guided Focused Ultrasound-Mediated Regional Brain Stimulation in Sheep.

    Science.gov (United States)

    Lee, Wonhye; Lee, Stephanie D; Park, Michael Y; Foley, Lori; Purcell-Estabrook, Erin; Kim, Hyungmin; Fischer, Krisztina; Maeng, Lee-So; Yoo, Seung-Schik

    2016-02-01

    Non-invasive brain stimulation using focused ultrasound has largely been carried out in small animals. In the present study, we applied stimulatory focused ultrasound transcranially to the primary sensorimotor (SM1) and visual (V1) brain areas in sheep (Dorset, all female, n = 8), under the guidance of magnetic resonance imaging, and examined the electrophysiologic responses. By use of a 250-kHz focused ultrasound transducer, the area was sonicated in pulsed mode (tone-burst duration of 1 ms, duty cycle of 50%) for 300 ms. The acoustic intensity at the focal target was varied up to a spatial peak pulse-average intensity (Isppa) of 14.3 W/cm(2). Sonication of SM1 elicited electromyographic responses from the contralateral hind leg, whereas stimulation of V1 generated electroencephalographic potentials. These responses were detected only above a certain acoustic intensity, and the threshold intensity, as well as the degree of responses, varied among sheep. Post-sonication animal behavior was normal, but minor microhemorrhages were observed from the V1 areas exposed to highly repetitive sonication (every second for ≥500 times for electroencephalographic measurements, Isppa = 6.6-10.5 W/cm(2), mechanical index = 0.9-1.2). Our results suggest the potential translational utility of focused ultrasound as a new brain stimulation modality, yet also call for caution in the use of an excessive number of sonications. PMID:26525652

  6. Novel magnetic/ultrasound focusing system enhances nanoparticle drug delivery for glioma treatment

    OpenAIRE

    Chen, Pin-Yuan; Liu, Hao-Li; Hua, Mu-Yi; Yang, Hung-Wei; Huang, Chiung-Yin; Chu, Po-Chun; Lyu, Lee-Ang; Tseng, I-Chou; Feng, Li-Ying; Tsai, Hong-Chieh; Chen, Shu-Mei; Lu, Yu-Jen; Wang, Jiun-Jie; Yen, Tzu-Chen; Ma, Yunn-Hwa

    2010-01-01

    Malignant glioma is a common and severe primary brain tumor with a high recurrence rate and an extremely high mortality rate within 2 years of diagnosis, even when surgical, radiological, and chemotherapeutic interventions are applied. Intravenously administered drugs have limited use because of their adverse systemic effects and poor blood–brain barrier penetration. Here, we combine 2 methods to increase drug delivery to brain tumors. Focused ultrasound transiently permeabilizes the blood–br...

  7. Focused Ultrasound Surgery for the Treatment of Recurrent Anaplastic Astrocytoma: A Preliminary Report

    Science.gov (United States)

    Park, Jung-Wuk; Jung, Shin; Jung, Tae-Young; Lee, Min-Cheol

    2006-05-01

    Anaplastic glioma is a highly aggressive tumor in the central nervous system. The conventional treatment for patients with anaplstic glioma consists of the combination of surgery, chemotherapy and radiotherapy. However, the effect of the currently available therapies is limited, and the prognosis is very poor in these patients. The purpose of this abstract is to introduce our preliminary experience of using focused ultrasound surgery (FUS) for the treatment of patients with recurrent anaplastic astrocytoma.

  8. Safety and Efficacy of Micro-focused Ultrasound Plus Visualization for the Treatment of Axillary Hyperhidrosis

    OpenAIRE

    Nestor, Mark S.; Park, Hyunhee

    2014-01-01

    Objectives: To evaluate the safety, efficacy, and durability of treating axillary hyperhidrosis with high-intensity micro-focused ultrasound plus visualization. Design: Two randomized double-blind, sham-controlled pilot studies. Measurements: For Study 1, the primary endpoint was response defined as ≥50-percent reduction in baseline sweat production as measured gravimetrically. For Study 2, the primary endpoint was response defined as a reduction of Hyperhidrosis Disease Severity Scale scores...

  9. High-Intensity Focused Ultrasound (HIFU) in Uterine Fibroid Treatment: Review Study

    OpenAIRE

    MAHMOUD, MUSTAFA Z.; Alkhorayef, Mohammed; Alzimami, Khalid S.; Aljuhani, Manal Saud; Sulieman, Abdelmoneim

    2014-01-01

    Summary Background 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. Material/Methods An inclusive literature review was carried out ...

  10. Laser-enhanced cavitation during high intensity focused ultrasound: An in vivo study

    Science.gov (United States)

    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 potential to enhance cavitation effect by reducing cavitation threshold in vivo. PMID:23653486

  11. Cavitation-based third ventriculostomy using MRI-guided focused ultrasound

    Science.gov (United States)

    Alkins, Ryan; Huang, Yuexi; Pajek, Dan; Hynynen, Kullervo

    2014-01-01

    Object Transcranial focused ultrasound is increasingly being investigated as a minimally invasive treatment for a range of intracranial pathologies. At higher peak rarefaction pressures than those used for thermal ablation, focused ultrasound can initiate inertial cavitation and create holes in the brain by fractionation of the tissue elements. The authors investigated the technical feasibility of using MRI-guided focused ultrasound to perform a third ventriculostomy as a possible noninvasive alternative to endoscopic third ventriculostomy for hydrocephalus. Methods A craniectomy was performed in male pigs weighing 13–19 kg to expose the supratentorial brain, leaving the dura mater intact. Seven pigs were treated through the craniectomy, while 2 pigs were treated through ex vivo human skulls placed in the beam path. Registration and targeting was done using T2-weighted MRI sequences. For transcranial treatments a CT scan was used to correct the beam from aberrations due to the skull and maintain a small, high-intensity focus. Sonications were performed at both 650 kHz and 230 kHz at a range of intensities, and the in situ pressures were estimated both from simulations and experimental data to establish a threshold for tissue fractionation in the brain. Results In craniectomized animals at 650 kHz, a peak pressure ≥ 22.7 MPa for 1 second was needed to reliably create a ventriculostomy. Transcranially at this frequency the ExAblate 4000 was unable to generate the required intensity to fractionate tissue, although cavitation was initiated. At 230 kHz, ventriculostomy was successful through the skull with a peak pressure of 8.8 MPa. Conclusions This is the first study to suggest that it is possible to perform a completely noninvasive third ventriculostomy using ultrasound. This may pave the way for future studies and eventually provide an alternative means for the creation of CSF communications in the brain, including perforation of the septum pellucidum or

  12. PATHOMORPHISM OF PROSTATE CANCER DURING HIGH-INTENSITY FOCUSED ULTRASOUND TREATMENT

    OpenAIRE

    R.N. Fomkin; E.S. Voronina; V.M. Popkov; G.N. Maslyakova; B. I. Blyumberg

    2014-01-01

    The purpose of the study was to evaluate the efficiency of prostate cancer (PC) treatment using high-intensity focused ultrasound (HIFU) on the basis of morphometric and immunohistochemical (IHC) analyses of postoperative prostate biopsy specimens. The study subjects were 40 patients with localized and locally advanced PC. The postoperative morphological analysis was made on the basis of standard hematoxylineosin staining and morphometric and IHC studies using the following antibodies: PCNA, ...

  13. High-Intensity Focused Ultrasound for Prostate Cancer: Long-Term Followup and Complications Rate

    OpenAIRE

    Umberto Maestroni; Francesco Dinale; Roberto Minari; Paolo Salsi; Francesco Ziglioli

    2012-01-01

    Introduction. As it is well known, High Intensity Focused Ultrasound (HIFU) is a minimally invasive procedure for prostate cancer. Many investigators reported their series of patients, demonstrating the effectiveness of the treatment. The most majority of Authors, however, do not report the side effects and the complications of the procedure, which is the aim of our study. The diagnosis and management of complications is discussed, and the oncologic outcome is reported in terms of quality of ...

  14. Histological changes in the human prostate after radiotherapy and salvage high intensity focused ultrasound

    OpenAIRE

    Chalasani, Venu; Martinez, Carlos H; Williams, Andrew K.; Kwan, Kevin; Chin, Joseph L.

    2010-01-01

    The histological changes (both macroscopic and microscopic) in the prostate following the combination of external beam radiotherapy and salvage high intensity focused ultrasound (HIFU) have not been previously described. This article describes the case of a 65-year-old male who presented with recurrent localized prostate cancer after undergoing external beam radiotherapy for low-risk prostate cancer. He was treated with salvage HIFU, and 4 weeks later presented with symptoms and signs consist...

  15. A Rectourethral Fistula due to Transrectal High-Intensity Focused Ultrasound Treatment: Diagnosis and Management

    OpenAIRE

    Valeria Fiaschetti; Guglielmo Manenti; Isabelle Di Poce; Maria Fornari; Aurora Ricci; Enrico Finazzi Agrò; Giovanni Simonetti

    2012-01-01

    Colovesical fistula (CVF) is an abnormal connection between the enteric and the urinary systems. The rectourethral fistula (RUF) is a possible but extremely rare complication of treatment of prostate cancer with “transrectal High-Intensity Focused Ultrasound (HIFU) treatment.” We present a case of CVF due to HIFU treatment of recurrent prostate cancer. The case was assessed with cystography completed with a pelvic CT scan—with MPR, MIP, and VR reconstruction—before emptying the bladder. Since...

  16. Urodynamic Evaluation after High-Intensity Focused Ultrasound for Patients with Prostate Cancer

    OpenAIRE

    Luigi Mearini; Elisabetta Nunzi; Silvia Giovannozzi; Luca Lepri; Carolina Lolli; Antonella Giannantoni

    2014-01-01

    This prospective study assesses the impact of high-intensity focused ultrasound (HIFU) on lower urinary tract by comparing pre- and postoperative symptoms and urodynamic changes. Thirty consecutive patients with clinically organ-confined prostate cancer underwent urodynamic study before HIFU and then at 3–6 months after surgery. Continence status and symptoms were analyzed by means of International Prostate Symptoms Score IPSS and International Index Erectile Function IIEF5. As a result, ther...

  17. Results of low threshold to biopsy following high-intensity focused ultrasound for localized prostate cancer

    OpenAIRE

    Richard L Haddad; Tania A Hossack; Woo, Henry H.

    2012-01-01

    Context: There are different treatment options for localized prostate cancer. The success of high-intensity focused ultrasound (HIFU) is based largely on biochemical prostate specific antigen (PSA) results. Aims: To evaluate the impact of using a low PSA threshold to perform prostate biopsies after HIFU in order to more accurately gauge treatment success. Settings and Design: Eleven patients underwent HIFU at Sydney Adventist Hospital in Sydney, 10 as primary and 1 as salvage therapy ...

  18. IN VIVO MONITORING OF FOCUSED ULTRASOUND SURGERY USING LOCAL HARMONIC MOTION

    OpenAIRE

    Curiel, Laura; Chopra, Rajiv; Hynynen, Kullervo

    2008-01-01

    The present study established the feasibility of a technique for monitoring FUS lesion formation in vivo using localized harmonic motion (LHM) measurements. Oscillatory motion (frequencies between 50 and 300 Hz) was generated within tissues by induction of a periodic radiation force with a focused ultrasound (FUS) transducer. The harmonic motion was estimated using cross-correlation of RF ultrasonic signals acquired at different instances during the motion by using a confocal diagnostic ultra...

  19. Modes of elastic plates and shells in water driven by modulated radiation pressure of focused ultrasound

    Science.gov (United States)

    Marston, Philip L.; Daniel, Timothy D.; Abawi, Ahmad T.; Kirsteins, Ivars

    2015-11-01

    The modulated radiation pressure (MRP) of ultrasound has been used for decades to selectively excite low frequency modes associated with surface tension of fluid objects in water. Much less is known about the excitation of low frequency modes of less compliant metallic objects. Here we use MRP of focused ultrasound to excite resonant flexural vibrations of a circular metal plate in water. The source transducer was driven with a double-sideband suppressed carrier voltage as in. The response of the target (detected with a hydrophone) was at twice the modulation frequency and proportional to the square of the drive voltage. Since the radiation pressure of focused beams is spatially localized, mode shapes could be identified by scanning the source along the target while measuring the target's response. Additional measurements were done with an open-ended water-filled copper circular cylindrical shell in which resonant frequencies and mode shapes were also identified. These experiments show how focused ultrasound can be used to identify low-frequency modes of elastic objects without direct contact. Supported by ONR.

  20. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  1. Magnetic resonance image-guided versus ultrasound-guided high-intensity focused ultrasound in the treatment of breast cancer

    Institute of Scientific and Technical Information of China (English)

    Sheng Li; Pei-Hong Wu

    2013-01-01

    Image-guided high-intensity focused ultrasound (HIFU) has been used for more than ten years,primarily in the treatment of liver and prostate cancers.HIFU has the advantages of precise cancer ablation and excellent protection of healthy tissue.Breast cancer is a common cancer in women.HIFU therapy,in combination with other therapies,has the potential to improve both oncologic and cosmetic outcomes for breast cancer patients by providing a curative therapy that conserves mammary shape.Currently,HIFU therapy is not commonly used in breast cancer treatment,and efforts to promote the application of HIFU is expected.In this article,we compare different image-guided models for HIFU and reviewed the status,drawbacks,and potential of HIFU therapy for breast cancer.

  2. Magnetic resonance image-guided versus ultrasound-guided high-intensity focused ultrasound in the treatment of breast cancer.

    Science.gov (United States)

    Li, Sheng; Wu, Pei-Hong

    2013-08-01

    Image-guided high-intensity focused ultrasound (HIFU) has been used for more than ten years, primarily in the treatment of liver and prostate cancers. HIFU has the advantages of precise cancer ablation and excellent protection of healthy tissue. Breast cancer is a common cancer in women. HIFU therapy, in combination with other therapies, has the potential to improve both oncologic and cosmetic outcomes for breast cancer patients by providing a curative therapy that conserves mammary shape. Currently, HIFU therapy is not commonly used in breast cancer treatment, and efforts to promote the application of HIFU is expected. In this article, we compare different image-guided models for HIFU and reviewed the status, drawbacks, and potential of HIFU therapy for breast cancer. PMID:23237221

  3. Single-element focused ultrasound transducer method for harmonic motion imaging.

    Science.gov (United States)

    Maleke, Caroline; Pernot, Mathieu; Konofagou, Elisa E

    2006-07-01

    The harmonic motion imaging (HMI) technique for simultaneous monitoring and generation of ultrasound therapy using two separate focused ultrasound transducer elements was previously demonstrated. In this study, a new HMI technique is described that images tissue displacement induced by a harmonic radiation force using a single focused-ultrasound element. A wave propagation simulation model first indicated that, unlike in the two-beam configuration, the amplitude-modulated beam produced a stable focal zone for the applied harmonic radiation force. The AM beam thus offered the unique advantage of sustaining the application of the spatially-invariant radiation force. Experiments were performed on gelatin phantoms and ex vivo tissues. The radiation force was generated by a 4.68 MHz focused ultrasound (FUS) transducer using a 50 Hz amplitude-modulated wave. A 7.5 MHz pulse-echo transducer was used to acquire rf echoes during the application of the harmonic radiation force. Consecutive rf echoes were acquired with a pulse repetition frequency (PRF) of 6.5 kHz and 1D cross-correlation was performed to estimate the resulting axial tissue displacement. The HMI technique was shown capable of estimating stiffness-dependent displacement amplitudes. Finally, taking advantage of the real-time capability of the HMI technique, temperature-dependent measurements enabled monitoring ofHIFU sonication in ex vivo tissues. The new HMI method may thus enable a highly-localized force and stiffness-dependent measurements as well as real-time and low-cost HIFU monitoring.

  4. High-Frequency Focused Water-Coupled Ultrasound Used for Three-Dimensional Surface Depression Profiling

    Science.gov (United States)

    Roth, Don J.; Whalen, Mike F.; Hendricks, J. Lynne; Bodis, James R.

    2001-01-01

    To interface with other solids, many surfaces are engineered via methods such as plating, coating, and machining to produce a functional surface ensuring successful end products. In addition, subsurface properties such as hardness, residual stress, deformation, chemical composition, and microstructure are often linked to surface characteristics. Surface topography, therefore, contains the signatures of the surface and possibly links to volumetric properties, and as a result serves as a vital link between surface design, manufacturing, and performance. Hence, surface topography can be used to diagnose, monitor, and control fabrication methods. At the NASA Glenn Research Center, the measurement of surface topography is important in developing high-temperature structural materials and for profiling the surface changes of materials during microgravity combustion experiments. A prior study demonstrated that focused air-coupled ultrasound at 1 MHz could profile surfaces with a 25-m depth resolution and a 400-m lateral resolution over a 1.4-mm depth range. In this work, we address the question of whether higher frequency focused water-coupled ultrasound can improve on these specifications. To this end, we employed 10- and 25-MHz focused ultrasonic transducers in the water-coupled mode. The surface profile results seen in this investigation for 25-MHz water-coupled ultrasound, in comparison to those for 1-MHz air-coupled ultrasound, represent an 8 times improvement in depth resolution (3 vs. 25 m seen in practice), an improvement of at least 2 times in lateral resolution (180 vs. 400 m calculated and observed in practice), and an improvement in vertical depth range of 4 times (calculated).

  5. Modeling and Predicting Tissue Movement and Deformation for High Intensity Focused Ultrasound Therapy

    Science.gov (United States)

    Liao, Xiangyun; Yuan, Zhiyong; Lai, Qianfeng; Guo, Jiaxiang; Zheng, Qi; Yu, Sijiao; Tong, Qianqian; Si, Weixin; Sun, Mingui

    2015-01-01

    Purpose In ultrasound-guided High Intensity Focused Ultrasound (HIFU) therapy, the target tissue (such as a tumor) often moves and/or deforms in response to an external force. This problem creates difficulties in treating patients and can lead to the destruction of normal tissue. In order to solve this problem, we present a novel method to model and predict the movement and deformation of the target tissue during ultrasound-guided HIFU therapy. Methods Our method computationally predicts the position of the target tissue under external force. This prediction allows appropriate adjustments in the focal region during the application of HIFU so that the treatment head is kept aligned with the diseased tissue through the course of therapy. To accomplish this goal, we utilize the cow tissue as the experimental target tissue to collect spatial sequences of ultrasound images using the HIFU equipment. A Geodesic Localized Chan-Vese (GLCV) model is developed to segment the target tissue images. A 3D target tissue model is built based on the segmented results. A versatile particle framework is constructed based on Smoothed Particle Hydrodynamics (SPH) to model the movement and deformation of the target tissue. Further, an iterative parameter estimation algorithm is utilized to determine the essential parameters of the versatile particle framework. Finally, the versatile particle framework with the determined parameters is used to estimate the movement and deformation of the target tissue. Results To validate our method, we compare the predicted contours with the ground truth contours. We found that the lowest, highest and average Dice Similarity Coefficient (DSC) values between predicted and ground truth contours were, respectively, 0.9615, 0.9770 and 0.9697. Conclusion Our experimental result indicates that the proposed method can effectively predict the dynamic contours of the moving and deforming tissue during ultrasound-guided HIFU therapy. PMID:25993644

  6. Modeling of Nonlinear Propagation in Multi-layer Biological Tissues for Strong Focused Ultrasound

    Institute of Scientific and Technical Information of China (English)

    FAN Ting-Bo; LIU Zhen-Bo; ZHANG Zhe; ZHANG DONG; GONG Xiu-Fen

    2009-01-01

    A theoretical model of the nonlinear propagation in multi-layered tissues for strong focused ultrasound is proposed. In this model, the spheroidal beam equation (SBE) is utilized to describe the nonlinear sound propagation in each layer tissue, and generalized oblique incidence theory is used to deal with the sound transmission between two layer tissues. Computer simulation is performed on a fat-muscle-liver tissue model under the irradiation of a 1 MHz focused transducer with a large aperture angle of 35°. The results demonstrate that the tissue layer would change the amplitude of sound pressure at the focal region and cause the increase of side petals.

  7. High-Intensity Focused Ultrasound (HIFU) in Localized Prostate Cancer Treatment

    International Nuclear Information System (INIS)

    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. 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.

  9. Study on focusing characteristic of acceleration tube in high current implanter

    International Nuclear Information System (INIS)

    The accelerating tube is one of the most important parts in high current implanter which provides the desired energy and focusing for ion beam. The factors affecting focus characteristic in high current implanter with three gap acceleration tube are discussed. Focusing degrees of different energy ion beam are computed, and the electric field required to prevent beam expansion due to space charge effect are analyzed. The beam envelope inside the three acceleration gap shows a decrease of the beam radius with the increase of the accelerating voltage ratio up to the optimal value. Beyond this optimal value the beam lines make a crossover with the axis of the accelerating tube

  10. Advantage of annular focus generation by sector-vortex array in cavitation-enhanced high-intensity focused ultrasound treatment

    Science.gov (United States)

    Jimbo, Hayato; Takagi, Ryo; Taguchi, Kei; Yoshizawa, Shin; Umemura, Shin-ichiro

    2016-07-01

    High-intensity focused ultrasound (HIFU) is a noninvasive method for cancer treatment. One of the disadvantages of this method is that it has a long total treatment time because of the smallness of the treatment volume by a single exposure. To solve this problem, we have proposed a method of cavitation-enhanced heating, which utilized the heat generated by oscillating the cavitation bubbles, in combination with the method of lateral enlargement of a HIFU focal zone to minimize the surface volume ratio. In a previous study, focal spot scanning at multiple points was employed for the enlargement. This method involves nonlinear propagation and absorption due to the high spatial-peak temporal-peak (SPTP) intensity in addition to the cavitation-enhanced heating. However, it is difficult to predict the size and position of the coagulation volume because they are significantly affected by the nonlinear parameters of the tissue. In this study, a sector vortex method was employed to directly synthesize an annular focal pattern. Since this method can keep the SPTP intensity at a manageably low level, nonlinear propagation and absorption can be minimized. Experimental results demonstrate that the coagulation was generated only in the region where both the cavitation cloud and the heating ultrasound were matched. The proposed method will make the cavitation-enhanced HIFU treatment more accurate and predictable.

  11. High intensity focused ultrasound ablation of pancreatic neuroendocrine tumours: report of two cases.

    Science.gov (United States)

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

    2011-04-01

    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. PMID:20521049

  12. An optimized ultrasound digital beamformer with dynamic focusing implemented on FPGA.

    Science.gov (United States)

    Almekkawy, Mohamed; Xu, Jingwei; Chirala, Mohan

    2014-01-01

    We present a resource-optimized dynamic digital beamformer for an ultrasound system based on a field-programmable gate array (FPGA). A comprehensive 64-channel receive beamformer with full dynamic focusing is embedded in the Altera Arria V FPGA chip. To improve spatial and contrast resolution, full dynamic beamforming is implemented by a novel method with resource optimization. This was conceived using the implementation of the delay summation through a bulk (coarse) delay and fractional (fine) delay. The sampling frequency is 40 MHz and the beamformer includes a 240 MHz polyphase filter that enhances the temporal resolution of the system while relaxing the Analog-to-Digital converter (ADC) bandwidth requirement. The results indicate that our 64-channel dynamic beamformer architecture is amenable for a low power FPGA-based implementation in a portable ultrasound system. PMID:25570695

  13. Novel Non-invasive Treatment With High-intensity Focused Ultrasound (HIFU).

    Science.gov (United States)

    Marinova, M; Rauch, M; Schild, H H; Strunk, H M

    2016-02-01

    Ultrasound is not only used for diagnostic purposes but it also can be applied therapeutically so far that nowadays high-intensity focused ultrasound (HIFU) even represents a novel non-invasive treatment modality for various solid tumors. HIFU works by causing selectively deep tissue destruction of target lesions within the body without harming adjacent and overlying structures. In this article, we present an overview on both the mode of action and requirements for a HIFU treatment as well as on the safety and the current status of indications and possible applications with regard to benign and malignant gynecological diseases. Based on numerous studies and original articles, HIFU proved to be an effective and low-risk treatment option particularly for uterine fibroids and adenomyosis, but it also seems to be effective for breast fibroadenomas or even for breast cancer in special cases and other rare entities. PMID:26251996

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Wen-Peng, E-mail: zwp215@163.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Chen, Jin-Yun, E-mail: chenjinyun2006@126.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Zhang, Lian, E-mail: zhangl@haifu.com.cn [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Clinical Center for Tumor Therapy of 2nd Affiliated Hospital of Chongqing Medical University, 74 Linjiang Road, Chongqing 400010 (China); Li, Quan, E-mail: 1013283493@qq.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Qin, Juan, E-mail: ant000999@163.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); and others

    2013-01-15

    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{sup 3} (interquartile range, 41.1–132.5 cm{sup 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. Feasibility of ultrasound-guided high intensity focused ultrasound ablating uterine fibroids with hyperintense on T2-weighted MR imaging

    International Nuclear Information System (INIS)

    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 cm3 (interquartile range, 41.1–132.5 cm3). 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

  16. Targeted and reversible blood-retinal barrier disruption via focused ultrasound and microbubbles.

    Directory of Open Access Journals (Sweden)

    Juyoung Park

    Full Text Available The blood-retinal barrier (BRB prevents most systemically-administered drugs from reaching the retina. This study investigated whether burst ultrasound applied with a circulating microbubble agent can disrupt the BRB, providing a noninvasive method for the targeted delivery of systemically administered drugs to the retina. To demonstrate the efficacy and reversibility of such a procedure, five overlapping targets around the optic nerve head were sonicated through the cornea and lens in 20 healthy male Sprague-Dawley rats using a 690 kHz focused ultrasound transducer. For BRB disruption, 10 ms bursts were applied at 1 Hz for 60 s with different peak rarefactional pressure amplitudes (0.81, 0.88 and 1.1 MPa. Each sonication was combined with an IV injection of a microbubble ultrasound contrast agent (Definity. To evaluate BRB disruption, an MRI contrast agent (Magnevist was injected IV immediately after the last sonication, and serial T1-weighted MR images were acquired up to 30 minutes. MRI contrast enhancement into the vitreous humor near targeted area was observed for all tested pressure amplitudes, with more signal enhancement evident at the highest pressure amplitude. At 0.81 MPa, BRB disruption was not detected 3 h post sonication, after an additional MRI contrast injection. A day after sonication, the eyes were processed for histology of the retina. At the two lower exposure levels (0.81 and 0.88 MPa, most of the sonicated regions were indistinguishable from the control eyes, although a few tiny clusters of extravasated erythrocytes (petechaie were observed. More severe retinal damage was observed at 1.1 MPa. These results demonstrate that focused ultrasound and microbubbles can offer a noninvasive and targeted means to transiently disrupt the BRB for ocular drug delivery.

  17. Magnetic resonance-guided focused ultrasound surgery for treatment of painful osseous metastases

    Science.gov (United States)

    Hurwitz, Mark; Machtinger, Ronit; Fennessy, Fiona

    2011-03-01

    Magnetic resonance guided focused ultrasound surgery (MRgFUS) is an emerging technology that can non-invasively heat and ablate targeted tissue utilizing ultrasound energy. Use of MR imaging for treatment guidance provides several key advantages over more widely used ultrasound guidance for focused ultrasound ablation. MR allows for precise targeting, detailed beam path visualization, real time non-invasive temperature measurement, and treatment feedback to ensure therapeutic goals are achieved. In the realm of oncology, management of painful bone metastases is a common and daunting clinical problem. The Insightec ExAblate System has been shown in phase I/II trials for treatment of bone metastases to have an excellent safety profile and high rates of pain response. An international multi-center phase III trial for patients with painful bone metastases or multiple myeloma who are not candidates for radiation therapy is currently open. Patients are randomized 3:1 to MRgFUS or sham treatment with crossover to study treatment allowed for sham failures. The primary study endpoint is assessment of pain control over 3 months following treatment. In addition safety, quality of life, cost effectiveness analysis, and patient perceived clinical benefit are also being assessed. Details of the MRgFUS system, technical and clinical therapeutic parameters, use of real time non-invasive MR thermometry, and examples of patient treatments with use of MRgFUS to treat bone metastases will be discussed. New directions in use of MRgFUS including an update on development of a new mobile applicator and integration of MRgFUS in multimodality oncologic care will also be presented.

  18. Electron Acceleration by a Focused Gaussian Laser Pulse in Vacuum

    Institute of Scientific and Technical Information of China (English)

    何峰; 余玮; 陆培祥; 徐涵

    2004-01-01

    By numerically solving the relativistic equations of motion of a single electron in laser fields modeled by a Gaussian laser beam, we get the trajectory and energy of the electron. When the drifting distance is comparable to or even longer than the corresponding Rayleigh length, the evolution of the beam waist cannot be neglected. The asymmetry of intensity in acceleration and deceleration leads to the conclusion that the electron can be accelerated effectively and extracted by the longitudinal ponderomotive force. For intensities above, an electron's energy gain about MeV can be realized, and the energetic electron is parallel with the propagation axis.

  19. High-intensity focused ultrasound for the treatment of solid tumor: Chinese clinical experience

    Science.gov (United States)

    Takeuchi, Akira; Zhang, Hong; Sun, Kun; Hasumura, Hiromi; Liu, Botao; Fu, Yurui; Yang, Zaocheng

    2006-05-01

    As a non-invasive modality, high-intensity focused ultrasound (HIFU) therapy has been received an interest for the treatment of solid tumor. There are some makers of HIFU for the equipment in China. The Sonic CZ901 is developed from the Mianyang stream that has a great advantage for guiding by color Doppler ultrasound imaging. For the research about possibility of this equipment, we evaluate the clinical usefulness to the solid tumor of HIFU treatment at Wujing general hospital in Beijing. We elucidate the result in 28 cases with benign and malignant tumor (Uterine myoma:16, Benign prostatic hypertrophy:5, Benign breast tumor:2, Breast cancer:1, Retroperitoneal tumor:1, Pheochromocytoma:1, Liver cancer: 2) . After 14˜90days, all cases show the reduction of tumor size (Max.3.2cm, Min.1.6cm, :Mean 2.2cm reduced), and the blood flow of tumor completely reduced in 7/23, partially reduced in16/23. Clinical symptoms disappeared in 7, clearly improved in 14, improved in 7. All treatments had no adverse event except for two cases of liver cancer. They felt an abdominal pain that controllable by medicine and it improved within 6hours. It is concluded that HIFU with guide by ultrasound imaging is very safe, painless and effective as the anti-tumor treatment.

  20. Shadow effects in simulated ultrasound images derived from computed tomography images using a focused beam tracing model

    DEFF Research Database (Denmark)

    Pham, An Hoai; Lundgren, Bo; Stage, Bjarne;

    2012-01-01

    developed, which makes the simulated ultrasound images appear more realistic. The method using a focused beam tracing model gives diffuse shadows that are similar to the ones observed in measurements on real objects. Ultrasound images of a cod (Gadus morhua) were obtained with a BK Medical 2202 Pro......Focus ultrasound scanner (BK Medical, Herlev, Denmark) equipped with a dedicated research interface giving access to beamformed radio frequency data. CT images were obtained with an Aquilion ONE Toshiba CT scanner (Toshiba Medical Systems Corp., Tochigi, Japan). CT data were mapped from Hounsfield units...... to backscatter strength, attenuation coefficients, and characteristic acoustic impedance. The focused beam tracing model was used to create maps of the transmission coefficient and scattering strength maps. FIELD II was then used to simulate an ultrasound image of 38.955.34.5 mm, using 106 point scatterers...

  1. Evaluation of pulsed high intensity focused ultrasound exposures on metastasis in a murine model

    OpenAIRE

    Hancock, Hilary; Dreher, Matthew R.; Crawford, Nigel; Pollock, Claire B.; Shih, Jennifer; Wood, Bradford J.; Hunter, Kent; Frenkel, Victor

    2009-01-01

    High intensity focused ultrasound (HIFU) may be employed in two ways: continuous exposures for thermal ablation of tissue (>60°C), and pulsed-exposures for non-ablative effects, including low temperature hyperthermia (37–45°C), and non thermal effects (e.g. acoustic cavitation and radiation forces). Pulsed-HIFU effects may enhance the tissue's permeability for improved delivery of drugs and genes, for example, by opening up gaps between cells in the vasculature and parenchyma. Inducing these ...

  2. HIGH INTENSITY FOCUSED ULTRASOUND FOR TREATMENT UNRESECTABLE MALIGNANT TUMORS IN 75 PATIENTS

    Institute of Scientific and Technical Information of China (English)

    郑国强

    2004-01-01

    Objective: To study preliminary experience of high intensity focused ultrasound (HIFU) for unresectable malignant tumors in 75 patients. Methods: The clinical data of 75 patients with unresectable tumor was analyzed retrospectively. Results: Among 75 patients, ten out of 57 cases achieved good local control in short-term, 5 patients liver tumor, 4 patients with tumor in the chest wall and one patient with bone matestics. Seven patients had skin burn and 2 patients developed intestinal perforations. Conclusion: HIFU is a novel tool for local tumor treatment. HIFU treatment for patients with unresectable tumor in the chest wall is effective.

  3. A boundary condition to the Khokhlov-Zabolotskaya equation for modeling strongly focused nonlinear ultrasound fields

    Energy Technology Data Exchange (ETDEWEB)

    Rosnitskiy, P., E-mail: pavrosni@yandex.ru; Yuldashev, P., E-mail: petr@acs366.phys.msu.ru; Khokhlova, V., E-mail: vera@acs366.phys.msu.ru [Physics Faculty, Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation)

    2015-10-28

    An equivalent source model was proposed as a boundary condition to the nonlinear parabolic Khokhlov-Zabolotskaya (KZ) equation to simulate high intensity focused ultrasound (HIFU) fields generated by medical ultrasound transducers with the shape of a spherical shell. The boundary condition was set in the initial plane; the aperture, the focal distance, and the initial pressure of the source were chosen based on the best match of the axial pressure amplitude and phase distributions in the Rayleigh integral analytic solution for a spherical transducer and the linear parabolic approximation solution for the equivalent source. Analytic expressions for the equivalent source parameters were derived. It was shown that the proposed approach allowed us to transfer the boundary condition from the spherical surface to the plane and to achieve a very good match between the linear field solutions of the parabolic and full diffraction models even for highly focused sources with F-number less than unity. The proposed method can be further used to expand the capabilities of the KZ nonlinear parabolic equation for efficient modeling of HIFU fields generated by strongly focused sources.

  4. Numerical simulation of ultrasound thermotherapy of brain with a scanned focus transducer

    Science.gov (United States)

    Behnia, Sohrab; Ghalichi, Farzan; Jafari, Amin; Bonabi, Ashkan

    2005-04-01

    Brain tumors are one of the most difficult ones to treat. The margin between destruction of the tumor and damage to the surrounding tissue is narrow in the brain. Ultrasound could be an effective treatment because of its ability to propagate deep in tissue and induce temperature rise at the focus while leaving the surrounding tissue intact. This study investigates whether using a fix-focus transducer could destroy brain tumor cells, in a cost effective manner which reduces the treatment time significantly. In this work an appropriate fix-focus transducer was designed considering effective parameters and limitations which are dominant in this case. Then a real 2-D brain model was constructed from a MR image. A piece of the skull bone has been removed to allow ultrasound to propagate into the brain. The resultant pressure field and the temperature rise were calculated by Rayleigh integral and bio-heat equation on the model. The obtained results were promising indicating that toxic temperatures could be obtained in short treatment times. This could be of great advantage especially in treating primary brain tumors.

  5. Impact of microbubble enhanced, pulsed, focused ultrasound on tumor circulation of subcutaneous VX2 cancer

    Institute of Scientific and Technical Information of China (English)

    Li Peijing; Zhu Mei; Xu Yali; Zhao Yang; Gao Shunji; Liu Zheng; Gao Yun-hua

    2014-01-01

    Background Intravascular microbubble-enhanced acoustic cavitation is capable of disrupting the vascular walls of capillaries and small vessels.This study was designed to investigate the impact of microbubble-enhanced,pulsed and focused ultrasound (MEUS) on the blood perfusion of subcutaneous VX2 tumors in rabbits.Methods Subcutaneous VX2 cancers in twenty New Zealand rabbits were treated by combining high-pressure amplitude,pulsed and focused therapeutic ultrasound (TUS) and intravenous microbubble injections.The TUS transducer was operated with a peak negative pressure of 4.6 MPa and a duty cycle of 0.41%.Controls were subcutaneous VX2 cancers treated with TUS or microbubbles only.Contrast-enhanced ultrasound (CEUS) and intravenous Evans Blue (EB) perfusion were performed to assess the tumor circulation.The tumor microvascular disruption was assessed by histological examination.Results CEUS showed that the tumor circulation almost vanished after MEUS treatment.The average peak grayscale value (GSV) of tumor CEUS dropped significantly from 84.1±22.4 to 15.8±10.8 in the MEUS-treated tumors but no significant GSV changes were found in tumors in the two control groups.The mean tumor EB content of the MEUS-treated tumors was significantly lower than that of the controls.Histological examination found scattered tumor microvascular disruption with intercellular edema after MEUS treatment.Conclusion The tumor circulation of VX2 cancers can be arrested or significantly reduced by MEUS due to microvascular disruption.

  6. High-Intensity Focused Ultrasound (HIFU) in Uterine Fibroid Treatment: Review Study

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    Liu Hao-Li

    2012-11-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions 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.

  8. Effect of acoustic streaming on tissue heating due to high-intensity focused ultrasound

    CERN Document Server

    Solovchuk, Maxim A; Thiriet, Marc; Lin, Win-Li

    2011-01-01

    The influences of blood vessels and focused location on temperature distribution during high-intensity focused ultrasound (HIFU) ablation of liver tumors is studied. A three-dimensional acoustics-thermal-fluid coupling model is employed to compute the temperature field in the hepatic cancerous region. The model is based on the linear Westervelt and bioheat equations as well as the nonlinear Navier-Stokes equations for the liver parenchyma and blood vessels. The effect of acoustic streaming is also taken into account in the present HIFU simulation study. Different blood vessel diameters and focal point locations were investigated. We found from this three-dimensional numerical study that in large blood vessels both the convective cooling and acoustic streaming can change considerably the temperature field and the thermal lesion near blood vessels. If the blood vessel is located within the beam width, both acoustic streaming and blood flow cooling effects should be taken into account. The predicted temperature ...

  9. The road to clinical use of high-intensity focused ultrasound for liver cancer: technical and clinical consensus

    OpenAIRE

    Aubry, Jean-Francois; Pauly, Kim,; Moonen, Chrit; Haar, Gail Ter; Ries, Mario; Salomir, Rares; Sokka, Sham; Sekins, Kevin,; Shapira, Yerucham; Ye, Fangwei; Huff-Simonin, Heather; Eames, Matt; Hananel, Arik; Kassell, Neal; Napoli, Alessandro

    2013-01-01

    International audience Clinical use of high-intensity focused ultrasound (HIFU) under ultrasound or MR guidance as a non-invasive method for treating tumors is rapidly increasing. Tens of thousands of patients have been treated for uterine fibroid, benign prostate hyperplasia, bone metastases, or prostate cancer. Despite the methods' clinical potential, the liver is a particularly challenging organ for HIFU treatment due to the combined effect of respiratory-induced liver motion, partial b...

  10. Focused ultrasound-mediated suppression of chemically-induced acute epileptic EEG activity

    Directory of Open Access Journals (Sweden)

    Chung Yong-An

    2011-03-01

    Full Text Available Abstract Background Epilepsy is a common neurological disorder, which is attributed to uncontrollable abnormal hyper-excitability of neurons. We investigated the feasibility of using low-intensity, pulsed radiation of focused ultrasound (FUS to non-invasively suppress epileptic activity in an animal model (rat, which was induced by the intraperitonial injection of pentylenetetrazol (PTZ. Results After the onset of induced seizures, FUS was transcranially administered to the brain twice for three minutes each while undergoing electroencephalographic (EEG monitoring. An air-backed, spherical segment ultrasound transducer (diameter: 6 cm; radius-of-curvature: 7 cm operating at a fundamental frequency of 690 KHz was used to deliver a train of 0.5 msec-long pulses of sonication at a repetitive rate of 100 Hz to the thalamic areas of the brain. The acoustic intensity (130 mW/cm2 used in the experiment was sufficiently within the range of safety guidelines for the clinical ultrasound imaging. The occurrence of epileptic EEG bursts from epilepsy-induced rats significantly decreased after sonication when it was compared to the pre-sonication epileptic state. The PTZ-induced control group that did not receive any sonication showed a sustained number of epileptic EEG signal bursts. The animals that underwent sonication also showed less severe epileptic behavior, as assessed by the Racine score. Histological analysis confirmed that the sonication did not cause any damage to the brain tissue. Conclusions These results revealed that low-intensity, pulsed FUS sonication suppressed the number of epileptic signal bursts using acute epilepsy model in animal. Due to its non-invasiveness and spatial selectivity, FUS may offer new perspectives for a possible non-invasive treatment of epilepsy.

  11. Spatio-temporal analysis of molecular delivery through the blood-brain barrier using focused ultrasound

    International Nuclear Information System (INIS)

    The deposition of gadolinium through ultrasound-induced blood-brain barrier (BBB) openings in the murine hippocampus was investigated. First, wave propagation simulations through the intact mouse skull revealed minimal beam distortion while thermal deposition simulations, at the same sonication parameters used to induce BBB opening in vivo, revealed temperature increases lower than 0.5 0C. The simulation results were validated experimentally in ex vivo skulls (m = 6) and in vitro tissue specimens. Then, in vivo mice (n = 9) were injected with microbubbles (Optison(TM); 25-50 μl) and sonicated (frequency: 1.525 MHz, pressure amplitudes: 0.5-1.1 MPa, burst duration: 20 ms, duty cycle: 20%, durations: 2-4 shots, 30 s per shot, 30 s interval) at the left hippocampus, through intact skin and skull. Sequential, high-resolution, T1-weighted MRI (9.4 Tesla, in-plane resolution: 75 μm, scan time: 45-180 min) with gadolinium (Omniscan(TM); 0.5 ml) injected intraperitoneally revealed a threshold of the BBB opening at 0.67 MPa and BBB closing within 28 h from opening. The contrast-enhancement area and gadolinium deposition path were monitored over time and the influence of vessel density, size and location was determined. Sonicated arteries, or their immediate surroundings, depicted greater contrast enhancement than sonicated homogeneous brain tissue regions. In conclusion, gadolinium was delivered through a transiently opened BBB and contained to a specific brain region (i.e., the hippocampus) using a single-element focused ultrasound transducer. It was also found that the amount of gadolinium deposited in the hippocampal region increased with the acoustic pressure and that the spatial distribution of the BBB opening was determined not only by the ultrasound beam, but also by the vasculature of the targeted brain region

  12. Empirical modeling of renal motion for improved targeting during focused ultrasound surgery.

    Science.gov (United States)

    Abhilash, R H; Chauhan, Sunita

    2013-05-01

    Non-invasive surgery looks at ways of eliminating physical contact with the target tissues while maintaining necessary levels of accuracy. Focused Ultrasound Surgery (FUS) is one such treatment modality, which uses a tightly focused beam of high intensity ultrasound to ablate tumors in various parts of the body. For trans-abdominal access, respiration induced movement of the tissue targets remains a major issue during FUS. Respiration induced movements are known to be significant in liver and kidney. In this paper, we attempt to address this problem using non-linear prediction and modeling techniques as applicable to kidney movement patterns. Kidney movement patterns are known to be three dimensional and vastly complicated compared to movement patterns of the liver. Monitoring and quantification of the nature and extent of kidney movement is yet to be explored in depth for effective compensation and accurate targeting. Apart from the respiratory cycle, the movement of the kidney is also affected by several factors, such as the movement of the ribs, spleen and liver. Modeling of these movements is imperative for motion adaptive FUS. Since kidney movements are highly subject specific, generic statistical models cannot be used for compensation. The system latency and real-time performance of the imaging modality also induce additional parametric dependence in target tracking. In this work, we focus on empirical modeling and prediction of the kidney movement to for error analysis and computing system latency. The accuracy of existing modeling techniques is compared with a newly developed empirical model. From the study conducted in healthy volunteers, it was found that the kidney movement was complex and subject specific and could be effectively modeled using the new shape function based model. The model was further fine-tuned using Kalman filter based predictors and Adaptive Neuro-Fuzzy Inference System (ANFIS) which gave more than 85% accuracy in prediction. PMID

  13. Targeted therapy of animal eyes with tumors by laser-generated focused ultrasound (Conference Presentation)

    Science.gov (United States)

    Lee, Taehwa; Luo, Wei; Demirci, Hakan; Guo, L. Jay

    2016-03-01

    Cavitation therapy based on high-amplitude focused ultrasound (e.g., Histotripsy) has shown great promise in clinical trials. The technique realizes localized treatments of tissues and diseased cells by controlling cavitation zones, which can be even smaller than its acoustic spot sizes. Also, the short pressure pulse used in the technique can minimize the unwanted heat accumulation, which the conventional piezoelectric transducers suffer from due to low operating frequencies and relatively long acoustic pulses. However, this modality requires bulky system composed of array of piezoelectric elements and electric amplifiers in order to obtain high pressure amplitude. Moreover, especially when treating an area much smaller than the acoustic spot size, this approach may be vulnerable to nucleation sites within the focal volume, which can potentially induce cavitation and thus enlarge the total treatment area. Here, we show targeted cell-level therapy by using laser generated ultrasound. By employing a concave lens coated by a carbon nanotube (CNT)-polymer composite, high-amplitude acoustic pressure can be obtained at a tight focal spot (level surgery to remove cells and to kill cells. Some experimental examples are shown using animal eyeballs.

  14. Analysis of clinical effect of high-intensity focused ultrasound on liver cancer

    Institute of Scientific and Technical Information of China (English)

    Chuan-Xing Li; Guo-Liang Xu; Zhen-You Jiang; Jian-Jun Li; Guang-Yu Luo; Hong-Bo Shan; Rong Zhang; Yin Li

    2004-01-01

    AIM: To evaluate the clinical effect of high-intensity focused ultrasound (HIFU) in the treatment of patients with liver cancer.METHODS: HIFU treatment was performed in 100 patients with liver cancer under general anesthesia and by a targeted ultrasound. Evaluation of efficacy was made on the basis of clinical symptoms, liver function tests, AFP,MRI or CT before and after the treatment.RESULTS: After HIFU treatment, clinical symptoms were relieved in 86.6%(71/82) of patients. The ascites disappeared in 6 patients. ALT (95±44) U/L and AST (114±58) U/L before HIFU treatment were reduced to normal in 83.3%(30/36) and 72.9%(35/48) patients,respectively, after the treatment. AFP was lowered by more than 50% in 65.3%(32/49) patients. After HIFU treatment,MRI or CT findings indicated coagulation necrosis and blood supply reduction or disappearance of tumor in the target region.CONCLUSION: HIFU can efficiently treat the patients with liver cancer. It will offer a significant noninvasive therapy for local treatment of liver tumor.

  15. Pathological changes on human breast cancer specimens ablated in vitro with high-intensity focused ultrasound.

    Science.gov (United States)

    Niu, Lingchuan; Wang, Zhibiao; Zou, Wenbing; Zhang, Lian; Xiang, Like; Zhu, Hui; Chen, Wenzhi; Bai, Jin; Wu, Junru

    2010-09-01

    The purpose of this study was to evaluate the pathologic changes of human breast cancer specimens ablated with high-intensity focused ultrasound (HIFU) in vitro. Twenty specimens of pathologically confirmed breast cancer tissue were ablated with ultrasound-guided HIFU. The evaluation methods include histopathologic observation using hematoxylin-eosin staining, electron microscopic imaging, enzyme histochemical and immunohistochemical examination on tumor antigens. Vacuole-like structures in cytoplasm were observed by histopathologic observation but there were no significant changes in cell morphology and nucleus karyotype. Typical phenomena related to coagulation necrosis were observed in electron microscopic studies; the contour of cell structure was still preserved but the structures of cell (all kinds of organelles and nucleus) were damaged or disappeared. Acid phosphatase and succinate dehydrogenase staining showed that tumor cells were inactivated. In immunohistochemical evaluations, estrogen receptor, progesterone receptor, cerbB-2 and P53 expression changed from 85%, 82%, 75% and 80% in nonablation tissue to no expression in ablated tumor tissue, respectively. We, therefore, conclude that breast cancer cells appear normal contour immediately after ablation with HIFU under light microscopic but they were evaluated to be dead by electron microscopic imaging, enzyme histochemical and immunohistochemical examinations. PMID:20800171

  16. High-Intensity Focused Ultrasound: Current Status for Image-Guided Therapy.

    Science.gov (United States)

    Copelan, Alexander; Hartman, Jason; Chehab, Monzer; Venkatesan, Aradhana M

    2015-12-01

    Image-guided high-intensity focused ultrasound (HIFU) is an innovative therapeutic technology, permitting extracorporeal or endocavitary delivery of targeted thermal ablation while minimizing injury to the surrounding structures. While ultrasound-guided HIFU was the original image-guided system, MR-guided HIFU has many inherent advantages, including superior depiction of anatomic detail and superb real-time thermometry during thermoablation sessions, and it has recently demonstrated promising results in the treatment of both benign and malignant tumors. HIFU has been employed in the management of prostate cancer, hepatocellular carcinoma, uterine leiomyomas, and breast tumors, and has been associated with success in limited studies for palliative pain management in pancreatic cancer and bone tumors. Nonthermal HIFU bioeffects, including immune system modulation and targeted drug/gene therapy, are currently being explored in the preclinical realm, with an emphasis on leveraging these therapeutic effects in the care of the oncology patient. Although still in its early stages, the wide spectrum of therapeutic capabilities of HIFU offers great potential in the field of image-guided oncologic therapy. PMID:26622104

  17. Sonablate-500TM Transrectal High-intensity Focused Ultrasound (HIFU) for Benign Prostatic Hyperplasia Patients

    Institute of Scientific and Technical Information of China (English)

    L(U) Jun; HU Weilie; WANG Wei; ZHANG Yuanfeng; CHEN Zhaoyang; YE Zhangqun

    2007-01-01

    To evaluate the safety and efficacy of transrectal high-intensity focused ultrasound (HIFU) in the treatment of benign prostatic hyperplasia (BPH), serial studies were conducted in 150 BPH pa- tients before and 30 min, 1, 2, 6 and 12 month(s) after Sonablate-500TM HIFU treatment. A sili- con-coated indwelling 16F latex catheter was placed during the determination of the therapy zone. Preoperative and postoperative evaluations were made by using the international prostate symptom score (IPSS), quality of life (QOL), uroflowmetric findings and transrectal ultrasound, and incidence of complications. The cystourethrography was done in 23 patients within 1 year postoperatively. The results showed that after HIFU treatment, IPSS and QOL scores were significantly decreased at 1, 2, 6 and 12 month(s) (P<0.01). Maximum urine flow rate (6.0 to 17.2 mL/s, P<0.01), PVR (75.0 to 30.3,P<0.01) and prostatic volume (65.0 to 38.1 mL, P<0.05) were significantly improved 12 months after the operation. Recurrent urinary retention (n=2) and urethrorectal fistula (n=1) occurred at the 15th postoperative day. The duration of the HIFU prostate ablation was 25-90 rain. The mean time for an indwelling catheter was 3-19 days. These data demonstrate that treatment of BPH with Sonab- late-500TM HIFU is safe and effective.

  18. Nonlinear 3-D simulation of high-intensity focused ultrasound therapy in the kidney

    CERN Document Server

    Suomi, Visa; Treeby, Bradley; Cleveland, Robin

    2016-01-01

    Kidney cancer is a severe disease which can be treated non-invasively using high-intensity focused ultrasound (HIFU) therapy. However, tissue in front of the transducer and the deep location of kidney can cause significant losses to the efficiency of the treatment. The effect of attenuation, refraction and reflection due to different tissue types on HIFU therapy of the kidney was studied using a nonlinear ultrasound simulation model. The geometry of the tissue was derived from a computed tomography (CT) dataset of a patient which had been segmented for water, bone, soft tissue, fat and kidney. The combined effect of inhomogeneous attenuation and sound-speed was found to result in an 11.0 dB drop in spatial peak-temporal average (SPTA) intensity in the kidney compared to pure water. The simulation without refraction effects showed a 6.3 dB decrease indicating that both attenuation and refraction contribute to the loss in focal intensity. The losses due to reflections at soft tissue interfaces were less than 0....

  19. The influence of viscosity on the shear strain remotely induced by focused ultrasound in viscoelastic media.

    Science.gov (United States)

    Barannik, E A; Girnyk, S A; Tovstiak, V V; Marusenko, A I; Volokhov, V A; Sarvazyan, A P; Emelianov, S Y

    2004-05-01

    Shear wave elasticity imaging (SWEI), an emerging acoustic technology for medical diagnostics, is based on remote generation of shear waves in tissue by radiation force in the focal region of an ultrasonic beam. In this study, the feasibility of Doppler ultrasonic technique to visualize the remotely induced shear waves was demonstrated. The generation of shear displacement in the focal region of a pulsed 1-MHz ultrasound beam with pulse duration of approximately about 2 ms and intensity levels on the order of 145 W/cm2, and consequent propagation of shear wave in tissue-mimicking and muscle tissue in vitro, were measured. The analysis of temporal behavior of shear displacement within the focal plane allowed estimation of shear wave velocities. The velocities were 4 and 7 m/s in hard phantom and tissue containing phantom, respectively. The measured shear displacements on the order of micrometers in gel-based phantoms are in reasonable agreement with theoretical estimates derived from an earlier developed model of shear wave generation by radiation force of focused ultrasound. The study revealed significant dependence of shear strain on the medium viscosity. The complex oscillatory character of shear strain relaxation in viscoelastic phantom and muscle tissue in vitro was observed. PMID:15139649

  20. Treating glioblastoma multiforme with selective high-dose liposomal doxorubicin chemotherapy induced by repeated focused ultrasound

    Directory of Open Access Journals (Sweden)

    Yang FY

    2012-02-01

    Full Text Available Feng-Yi Yang1, Ming-Che Teng1, Maggie Lu2, Hsiang-Fa Liang2, Yan-Ru Lee1, Chueh-Chuan Yen3, Muh-Lii Liang4,5, Tai-Tong Wong51Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 2Drug Delivery Laboratory, Biomedical Technology and Device Research Laboratories, Industrial Technology Research Institute, Hsinchu, 3Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, 4Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei, 5Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei, TaiwanBackground: High-dose tissue-specific delivery of therapeutic agents would be a valuable clinical strategy. We have previously shown that repeated transcranial focused ultrasound is able to increase the delivery of Evans blue significantly into brain tissue. The present study shows that repeated pulsed high-intensity focused ultrasound (HIFU can be used to deliver high-dose atherosclerotic plaque-specific peptide-1 (AP-1-conjugated liposomes selectively to brain tumors.Methods: Firefly luciferase (Fluc-labeled human GBM8401 glioma cells were implanted into NOD-scid mice. AP-1-conjugated liposomal doxorubicin or liposomal doxorubicin alone was administered followed by pulsed HIFU and the doxorubicin concentration in the treated brains quantified by fluorometer. Growth of the labeled glioma cells was monitored through noninvasive bioluminescence imaging and finally the brain tissue was histologically examined after sacrifice.Results: Compared with the control group, the animals treated with 5 mg/kg injections of AP-1 liposomal doxorubicin or untargeted liposomal doxorubicin followed by repeated pulsed HIFU not only showed significantly enhanced accumulation of drug at the sonicated tumor site but also a significantly elevated tumor-to-normal brain drug

  1. Tapered plasma channels to phase-lock accelerating and focusing forces in laser-plasma accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Rittershofer, W.; Schroeder, C.B.; Esarey, E.; Gruner, F.J.; Leemans, W.P.

    2010-05-17

    Tapered plasma channels are considered for controlling dephasing of a beam with respect to a plasma wave driven by a weakly-relativistic, short-pulse laser. Tapering allows for enhanced energy gain in a single laser plasma accelerator stage. Expressions are derived for the taper, or longitudinal plasma density variation, required to maintain a beam at a constant phase in the longitudinal and/or transverse fields of the plasma wave. In a plasma channel, the phase velocities of the longitudinal and transverse fields differ, and, hence, the required tapering differs. The length over which the tapered plasma density becomes singular is calculated. Linear plasma tapering as well as discontinuous plasma tapering, which moves beams to adjacent plasma wave buckets, are also considered. The energy gain of an accelerated electron in a tapered laser-plasma accelerator is calculated and the laser pulse length to optimize the energy gain is determined.

  2. Jet atomization and cavitation induced by interactions between focused ultrasound and a water surfacea)

    Science.gov (United States)

    Tomita, Y.

    2014-09-01

    Atomization of a jet produced by the interaction of 1 MHz focused ultrasound with a water surface was investigated using high-speed photography. Viewing various aspects of jet behavior, threshold conditions were obtained necessary for water surface elevation and jet breakup, including drop separation and spray formation. In addition, the position of drop atomization, where a single drop separates from the tip of a jet without spraying, showed good correlation with the jet Weber number. For a set of specified conditions, multiple beaded water masses were formed, moving upwards to produce a vigorous jet. Cavitation phenomena occurred near the center of the primary drop-shaped water mass produced at the leading part of the jet; this was accompanied by fine droplets at the neck between the primary and secondary drop-shaped water masses, due to the collapse of capillary waves.

  3. The Efficacy of High-Intensity Focused Ultrasound (HIFU) in Advanced Pancreatic Cancer

    Institute of Scientific and Technical Information of China (English)

    Bo Xie; Jiajun Ling; Weiming Zhang; Xueqin Huang; Jihua Zhen; Yanzhe Huang

    2008-01-01

    OBJECTIVE To observe the efficacy of high-intensity focused ultrasound (HIFU)in the treatment of late-stage pancreatic cancer.METHODS Sixteen patients with advanced pancreatic cancer received HIFU therapy.Evaluation of efficacy was made on the basis of changes in clinical symptoms and variations in the tumor echo and size.RESULTS Clinical symptoms such as pain were significantly alleviated,echo of the tumor was enhanced with B-US and the quality of life such as eating,sleeping and mental status was markedly improved;no serious complications were observed.CONCLUSION The use of HIFU in the treatment of advanced pancreatic cancer is feasible and safe.It is effective in killing the carcinoma cells and alleviaring pain.This technique may offer non-invasive therapy for the treatment of patients with late-stage pancreatic cancer.

  4. Experimental ablation of the pancreas with high intensity focused ultrasound (HIFU in a porcine model

    Directory of Open Access Journals (Sweden)

    Biao Xie, Yu-Yuan Li, Lin Jia, Yu-Qiang Nie, Hong Du, Shu-Man Jiang

    2011-01-01

    Full Text Available The aim of this study was to determine the feasibility and safety of high intensity focused ultrasound's (HIFU in pancreatic diseases. Twelve pigs were divided into three groups. The pancreases of pigs in Group A were ablated directly with HIFU, but those in Group B and C ablated by extracorporeal HIFU. The pigs in Group C were sacrificed at day 7 after HIFU. Serological parameters were determined pre-operation and post-operation. The entire pancreas was removed for histological examination. Each animal tolerate the HIFU ablation well. The complete necrosis was observed in targeted regions. The margins of the necrotic regions were clearly delineated from the surrounding normal tissues. Infiltration of inflammatory cells and phorocytosis on the boundary were found in group C. Blood and urine amylase levels were relatively steady after HIFU. No acute pancreatitis or severe complications occurred. In conclusion, HIFU ablation on the pancreas was safe and effective in experimental pigs.

  5. Influence of the abdominal wall on the nonlinear propagation of focused therapeutic ultrasound

    Institute of Scientific and Technical Information of China (English)

    Liu Zhen-Bo; Fan Ting-Bo; Zhang Dong; Gong Xiu-Fen

    2009-01-01

    y This article theoretically studies the influence of inhomogeneous abdominal walls on focused therapeutic ultrasound based on the phase screen model. An inhomogeneous tissue is considered as a combination of a homogeneous medium and a phase aberration screen. Variations of acoustic parameters such as peak positive pressure, peak negative pressure, and acoustic intensity are discussed with respect to the phase screen statistics of human abdominal walls. Results indicate that the abdominal wall can result in energy loss of the sound in the focal plane. For a typical human abdominal wall with correlation length of 7.9 mm and variance of 0.36, the peak acoustic intensity radiated from a 1 MHz transmitter with a radius of 30 mm can be reduced by about 14% at the focal plane.

  6. Functional Neurosurgery in the Human Thalamus by Transcranial Magnetic Resonance Guided Focused Ultrasound

    Science.gov (United States)

    Werner, Beat; Morel, Anne; Jeanmonod, Daniel; Martin, Ernst

    2009-04-01

    Potential applications of Transcranial Magnetic Resonance guided Focused Ultrasound (TcMRgFUS) include treatment of functional brain disorders, such as Parkinson's disease, dystonia and tremor, neurogenic pain and tinnitus, neuropsychiatric disorders and epilepsy. In this study we demonstrate the feasibility of non-invasive TcMRgFUS ablation of clinically well established targets in the human thalamus that are currently accessed stereotactically by interventional strategies based on the concept of the thalamocortical dysrhythmia (TCD). Thermal hotspots suitable for clinical intervention were created successfully in anatomical preparations of human ex-vivo heads under pseudo clinical conditions. The hotspots could be positioned at the target locations as needed and local energy deposition was sufficient to create tissue ablation. Numerical simulations based on these experimental data predict that the acoustic energy needed to create ablative lesions in-vivo will be within limits that can safely applied.

  7. Investigations on the heating effect of PE-LD induced by high-intensity focused ultrasound.

    Science.gov (United States)

    Oehm, Lukas; Bach, Sascha; Majschak, Jens-Peter

    2016-08-01

    High-intensity focused ultrasound is widely applied in tissue treatment as well as for heating of solid polymer materials. Previous studies investigating the heating effect in polymer materials utilized sound transmission through water or other fluids at low HIFU power. In this study, the ultrasonic transducer possesses a solid sound conductor made of aluminum and a high HIFU power of above 100W was applied to heat solid PE-LD samples. Temperature measurements were performed by calibrated non-invasive infrared thermal imaging. A strong heating effect with heating above melting temperature and evaporation temperature within less than 1s of irradiation was observed. Furthermore, the acoustic coupling defined by the force applied by the ultrasonic applicator to the polymer material was found to be fundamental to induce the heating effect. This investigation reveals HIFU for new applications in the field of polymer processing.

  8. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) treatment for uterine fibroids

    Science.gov (United States)

    Abdullah, BJJ; Subramaniam, RV; Omar, SS; Wragg, P; Ramli, N; Wui, AL; Lee, CC; Yusof, Y

    2010-01-01

    Magnetic Resonance-guided focused Ultrasound Surgery (MRgFUS) is gaining popularity as an alternative to medical and surgical interventions in the management of symptomatic uterine fibroids. Studies have shown that it is an effective non-invasive treatment with minimal associated risks as compared to myomectomy and hysterectomy. MRgFUS can be offered to a majority of patients suffering from symptomatic uterine fibroids. It has been suggested that the use of broader inclusion criteria as well as the mitigation techniques makes it possible to offer MRgFUS to a much larger subset of patients than previously believed. This paper will describe how MRgFUS treatment for uterine fibroids is performed at the University of Malaya Medical Centre, Kuala Lumpur, Malaysia. PMID:21611036

  9. Focused ultrasound-mediated drug delivery through the blood-brain barrier.

    Science.gov (United States)

    Burgess, Alison; Shah, Kairavi; Hough, Olivia; Hynynen, Kullervo

    2015-05-01

    Despite recent advances in blood-brain barrier (BBB) research, it remains a significant hurdle for the pharmaceutical treatment of brain diseases. Focused ultrasound (FUS) is one method to transiently increase permeability of the BBB to promote drug delivery to specific brain regions. An introduction to the BBB and a brief overview of the methods, which can be used to circumvent the BBB to promote drug delivery, is provided. In particular, we discuss the advantages and limitations of FUS technology and the efficacy of FUS-mediated drug delivery in models of disease. MRI for targeting and evaluating FUS treatments, combined with administration of microbubbles, allows for transient, reproducible BBB opening. The integration of a real-time acoustic feedback controller has improved treatment safety. Successful clinical translation of FUS has the potential to transform the treatment of brain disease worldwide without requiring the development of new pharmaceutical agents.

  10. Clinical evaluation of high-intensity focused ultrasound in treating uterus myomas

    International Nuclear Information System (INIS)

    Objective: To explore the safety and efficacy of high-intensity focused ultrasound (HIFU) for the treatment of uterus myomas. Methods: HIFU was performed in 47 patients with symptomatic hysteromyoma, who had a childbearing history and were 26-59 years old. Postoperative follow-up was carried out. Clinical symptoms and the tumor's size were observed before and after the HIFU treatment. The results were compared with each other. Results: After HIFU treatment, the symptoms such as dysmenorrhea and hypermenorrhea were markedly improved. Some patients developed hematuria or lower limb pain, which was relieved after symptomatic management. The average volume of myoma before the treatment was (47.6 ± 24.1) cm3 and it was reduced to (17.7 ± 13.1) cm3 at 6 months after the treatment, the difference was statistically significant (P < 0.05). Conclusion: HIFU is a safe and effective treatment for uterus myomas. (authors)

  11. A Rectourethral Fistula due to Transrectal High-Intensity Focused Ultrasound Treatment: Diagnosis and Management

    Directory of Open Access Journals (Sweden)

    Valeria Fiaschetti

    2012-01-01

    Full Text Available Colovesical fistula (CVF is an abnormal connection between the enteric and the urinary systems. The rectourethral fistula (RUF is a possible but extremely rare complication of treatment of prostate cancer with “transrectal High-Intensity Focused Ultrasound (HIFU treatment.” We present a case of CVF due to HIFU treatment of recurrent prostate cancer. The case was assessed with cystography completed with a pelvic CT scan—with MPR, MIP, and VR reconstruction—before emptying the bladder. Since the CT scan confirmed that the fistula involved solely the urethra and excluded even a minimal involvement of the bladder, it was possible to employ a conservative treatment by positioning a Foley catheter of monthly duration, in order to allow the urethra to rest. Still today, after 6 months, the patient is in a good clinical condition and has not shown yet signs of a recurrence of the fistula.

  12. Investigations on the heating effect of PE-LD induced by high-intensity focused ultrasound.

    Science.gov (United States)

    Oehm, Lukas; Bach, Sascha; Majschak, Jens-Peter

    2016-08-01

    High-intensity focused ultrasound is widely applied in tissue treatment as well as for heating of solid polymer materials. Previous studies investigating the heating effect in polymer materials utilized sound transmission through water or other fluids at low HIFU power. In this study, the ultrasonic transducer possesses a solid sound conductor made of aluminum and a high HIFU power of above 100W was applied to heat solid PE-LD samples. Temperature measurements were performed by calibrated non-invasive infrared thermal imaging. A strong heating effect with heating above melting temperature and evaporation temperature within less than 1s of irradiation was observed. Furthermore, the acoustic coupling defined by the force applied by the ultrasonic applicator to the polymer material was found to be fundamental to induce the heating effect. This investigation reveals HIFU for new applications in the field of polymer processing. PMID:27208613

  13. Preliminary assessment of one-dimensional MR elastography for use in monitoring focused ultrasound therapy

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Le [Mayo Graduate School, Mayo Clinic College of Medicine, Rochester, MN 55905 (United States); Glaser, Kevin J [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States); Rouviere, Olivier [Department of GenitoUrinary Radiology, Hopital E Herriot, 5, place d' Arsonval, 69003 Lyon (France); Gorny, Krzysztof R [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States); Chen, Shigao [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States); Manduca, Armando [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States); Ehman, Richard L [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States); Felmlee, Joel P [Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic Foundation, 200 1st St. SW, Rochester, MN 55905, Rochester, MN 55905 (United States)

    2007-09-21

    The purpose of this work is to assess a fast technique that measures tissue stiffness and temperature during focused ultrasound thermal therapy (FUS). A one-dimensional (1D) MR elastography (MRE) pulse sequence was evaluated for the purpose of obtaining rapid measurements of thermally induced changes in tissue stiffness and temperature for monitoring FUS treatments. The accuracy of the 1D measurement was studied by comparing tissue displacements measured by 1D MRE with those measured by the well-established 2D MRE pulse sequence. The reproducibility of the 1D MRE measurement was assessed, in gel phantoms and ex vivo porcine tissue, for varied FUS intensity levels (31.5-199.9 W cm{sup -2}) and over a range of displacements at the focus (0.1-1 {mu}m). Temperature elevations in agarose gel phantoms were measured using 1D MRE and calibrated using fiberoptic-thermometer-based measurements. The 1D MRE displacement measurements are highly correlated with those obtained with the 2D technique (R{sup 2} = 0.88-0.93), indicating that 1D MRE can successfully measure tissue displacement. Ten repeated trials at each FUS power level yielded a minimum detectable displacement change of 0.2 {mu}m in phantoms and 0.4 {mu}m in tissue (at 95% confidence level). The 1D MRE temperature measurements correlated well with temperature changes measured simultaneously with fiberoptic thermometers (R{sup 2} = 0.97). The 1D MRE technique is capable of detecting tissue displacements as low as 0.4 {mu}m, which is an order of magnitude smaller than 5 {mu}m displacements expected during FUS therapy (Le et al 2005 AIP Conf. Proc.: Ther. Ultrasound 829 186-90). Additionally, 1D MRE was shown to provide adequate measurements of temperature elevations in tissue. These findings indicate that 1D MRE may be an effective tool for monitoring FUS treatments.

  14. MR guided focused ultrasound: technical acceptance measures for a clinical system

    International Nuclear Information System (INIS)

    Magnetic resonance (MR) guided focused ultrasound (MRgFUS) is a hybrid technique which offers efficient and safe focused ultrasound (FUS) treatments of uterine fibroids under MR guidance and monitoring. As a therapy device, MRgFUS requires systematic testing over a wide range of operational parameters prior to use in the clinical environment. We present technical acceptance tests and data for the first clinical MRgFUS system, ExAblate (registered) 2000 (InSightec Inc., Haifa, Israel), that has been FDA approved for treating uterine fibroids. These tests characterize MRgFUS by employing MR temperature measurements in tissue mimicking phantoms. The coronal scan plane is empirically demonstrated to be most reliable for measuring temperature elevations resulting from high intensity ultrasound (US) pulses ('sonications') and shows high sensitivity to changes in sonication parameters. Temperatures measured in the coronal plane were used as a measure of US energy deposited within the focal spot for a range of sonication parameters used in clinical treatments: spot type, spot length, output power, sonication duration, US frequency, and depth of sonication. In addition, MR images acquired during sonications were used to measure effective diameters and lengths of available sonication spot types and lengths. At a constant 60 W output power, the effective spot type diameters were measured to vary between 4.7 ± 0.3 mm and 6.6 ± 0.4 mm; treatment temperatures were found to decrease with increasing spot diameter. Prescribing different spot lengths was found to have no effect on the measured length or on measured temperatures. Tests of MRgFUS positioning accuracy determined errors in the direction parallel to the propagation of the US beam to be significantly greater than those in the perpendicular direction; most sonication spots were erroneously positioned towards the FUS transducer. The tests reported here have been demonstrated to be sufficiently sensitive to detect water

  15. MR guided focused ultrasound: technical acceptance measures for a clinical system

    Energy Technology Data Exchange (ETDEWEB)

    Gorny, K R; Hangiandreou, N J; Hesley, G K; Gostout, B S; McGee, K P; Felmlee, J P [Department of Radiology, Mayo Clinic, Rochester, MN 55905 (United States)

    2006-06-21

    Magnetic resonance (MR) guided focused ultrasound (MRgFUS) is a hybrid technique which offers efficient and safe focused ultrasound (FUS) treatments of uterine fibroids under MR guidance and monitoring. As a therapy device, MRgFUS requires systematic testing over a wide range of operational parameters prior to use in the clinical environment. We present technical acceptance tests and data for the first clinical MRgFUS system, ExAblate (registered) 2000 (InSightec Inc., Haifa, Israel), that has been FDA approved for treating uterine fibroids. These tests characterize MRgFUS by employing MR temperature measurements in tissue mimicking phantoms. The coronal scan plane is empirically demonstrated to be most reliable for measuring temperature elevations resulting from high intensity ultrasound (US) pulses ('sonications') and shows high sensitivity to changes in sonication parameters. Temperatures measured in the coronal plane were used as a measure of US energy deposited within the focal spot for a range of sonication parameters used in clinical treatments: spot type, spot length, output power, sonication duration, US frequency, and depth of sonication. In addition, MR images acquired during sonications were used to measure effective diameters and lengths of available sonication spot types and lengths. At a constant 60 W output power, the effective spot type diameters were measured to vary between 4.7 {+-} 0.3 mm and 6.6 {+-} 0.4 mm; treatment temperatures were found to decrease with increasing spot diameter. Prescribing different spot lengths was found to have no effect on the measured length or on measured temperatures. Tests of MRgFUS positioning accuracy determined errors in the direction parallel to the propagation of the US beam to be significantly greater than those in the perpendicular direction; most sonication spots were erroneously positioned towards the FUS transducer. The tests reported here have been demonstrated to be sufficiently sensitive to

  16. Focused ultrasound solid-liquid extraction for the determination of organic biomarkers in beachrocks.

    Science.gov (United States)

    Blanco-Zubiaguirre, L; Arrieta, N; Iturregui, A; Martinez-Arkarazo, I; Olivares, M; Castro, K; Olazabal, M A; Madariaga, J M

    2015-11-01

    Beachrocks are consolidated coastal sedimentary formations resulting mainly from the relative rapid cementation of beach sediments by different calcium carbonate polymorphs. Although previous works have already studied the elemental composition and the mineral phases composing these cements, few of them have focused their attention on the organic matter present therein. This work describes an extraction methodology based on focused ultrasound solid-liquid extraction (FUSLE), followed by analysis using large volume injection (LVI) in a programmable temperature vaporizer (PTV) combined with gas chromatography-mass spectrometry (GC-MS) in order to determine organics such as polycyclic aromatic hydrocarbons (PAHs) and biomarkers (hopanes), which can increase and confirm the information obtained so far. This goal has been achieved after the optimization of the main parameters affecting the extraction procedure, such as, extraction solvent, FUSLE variables (amplitude, extraction time and pulse time) and also variables affecting the LVI-PTV (vent time, injection speed and cryo-focusing temperature). The developed method rendered results comparable to traditional extraction methods in terms of accuracy (77-109%) and repeatability (RSD<23%). Finally, the analyses performed over real beachrock samples from the Bay of Biscay (Northern Spain) revealed the presence of the 16 EPA priority PAHs, as well as some organic biomarkers which could increase the knowledge about such beachrock formation.

  17. Charged particle driver for ICF using an accelerated, focused compact torus

    International Nuclear Information System (INIS)

    We report the status of evaluating an accelerated and focused compact torus as a driver for ICF. We are studying the acceleration and focusing aspects experimentally in the RACE facility, a recently completed ring generator coupled to a 260 kJ acceleration bank. Compact torus and ICF target interaction is being investigated with PIC codes and LASNEX, a 2D magneto-hydrodynamics code. Final conditions required of the CT are discussed as well as coupling issues such as superthermal electron production. We conclude with an economic evaluation of a few 100 MW reactor driven by a compact torus. 9 refs., 5 figs., 1 tab

  18. Focused Ultrasound Simultaneous Irradiation/MRI Imaging, and Two-Stage General Kinetic Model

    Science.gov (United States)

    Huang, Sheng-Yao; Ko, Chia-En; Chen, Gin-Shin; Chung, I-Fang; Yang, Feng-Yi

    2014-01-01

    Many studies have investigated how to use focused ultrasound (FUS) to temporarily disrupt the blood-brain barrier (BBB) in order to facilitate the delivery of medication into lesion sites in the brain. In this study, through the setup of a real-time system, FUS irradiation and injections of ultrasound contrast agent (UCA) and Gadodiamide (Gd, an MRI contrast agent) can be conducted simultaneously during MRI scanning. By using this real-time system, we were able to investigate in detail how the general kinetic model (GKM) is used to estimate Gd penetration in the FUS irradiated area in a rat's brain resulting from UCA concentration changes after single FUS irradiation. Two-stage GKM was proposed to estimate the Gd penetration in the FUS irradiated area in a rat's brain under experimental conditions with repeated FUS irradiation combined with different UCA concentrations. The results showed that the focal increase in the transfer rate constant of Ktrans caused by BBB disruption was dependent on the doses of UCA. Moreover, the amount of in vivo penetration of Evans blue in the FUS irradiated area in a rat's brain under various FUS irradiation experimental conditions was assessed to show the positive correlation with the transfer rate constants. Compared to the GKM method, the Two-stage GKM is more suitable for estimating the transfer rate constants of the brain treated with repeated FUS irradiations. This study demonstrated that the entire process of BBB disrupted by FUS could be quantitatively monitored by real-time dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). PMID:24949997

  19. Focused ultrasound simultaneous irradiation/MRI imaging, and two-stage general kinetic model.

    Directory of Open Access Journals (Sweden)

    Sheng-Yao Huang

    Full Text Available Many studies have investigated how to use focused ultrasound (FUS to temporarily disrupt the blood-brain barrier (BBB in order to facilitate the delivery of medication into lesion sites in the brain. In this study, through the setup of a real-time system, FUS irradiation and injections of ultrasound contrast agent (UCA and Gadodiamide (Gd, an MRI contrast agent can be conducted simultaneously during MRI scanning. By using this real-time system, we were able to investigate in detail how the general kinetic model (GKM is used to estimate Gd penetration in the FUS irradiated area in a rat's brain resulting from UCA concentration changes after single FUS irradiation. Two-stage GKM was proposed to estimate the Gd penetration in the FUS irradiated area in a rat's brain under experimental conditions with repeated FUS irradiation combined with different UCA concentrations. The results showed that the focal increase in the transfer rate constant of Ktrans caused by BBB disruption was dependent on the doses of UCA. Moreover, the amount of in vivo penetration of Evans blue in the FUS irradiated area in a rat's brain under various FUS irradiation experimental conditions was assessed to show the positive correlation with the transfer rate constants. Compared to the GKM method, the Two-stage GKM is more suitable for estimating the transfer rate constants of the brain treated with repeated FUS irradiations. This study demonstrated that the entire process of BBB disrupted by FUS could be quantitatively monitored by real-time dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI.

  20. 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

  1. A fast boundary element method for the scattering analysis of high-intensity focused ultrasound.

    Science.gov (United States)

    van 't Wout, Elwin; Gélat, Pierre; Betcke, Timo; Arridge, Simon

    2015-11-01

    High-intensity focused ultrasound (HIFU) techniques are promising modalities for the non-invasive treatment of cancer. For HIFU therapies of, e.g., liver cancer, one of the main challenges is the accurate focusing of the acoustic field inside a ribcage. Computational methods can play an important role in the patient-specific planning of these transcostal HIFU treatments. This requires the accurate modeling of acoustic scattering at ribcages. The use of a boundary element method (BEM) is an effective approach for this purpose because only the boundaries of the ribs have to be discretized instead of the standard approach to model the entire volume around the ribcage. This paper combines fast algorithms that improve the efficiency of BEM specifically for the high-frequency range necessary for transcostal HIFU applications. That is, a Galerkin discretized Burton-Miller formulation is used in combination with preconditioning and matrix compression techniques. In particular, quick convergence is achieved with the operator preconditioner that has been designed with on-surface radiation conditions for the high-frequency approximation of the Neumann-to-Dirichlet map. Realistic computations of acoustic scattering at 1 MHz on a human ribcage model demonstrate the effectiveness of this dedicated BEM algorithm for HIFU scattering analysis. PMID:26627749

  2. Cell apoptosis and proliferation inhibition of pancreatic cancer induced by sub-threshold focused ultrasound (FUS)

    International Nuclear Information System (INIS)

    Objective: To evaluate the effects of sub-threshold focused ultrasound (FUS) sonication on the pancreatic cancer cell. Materials and methods: The human pancreatic carcinoma cell line PaTu 8988t suspension and pancreatic carcinoma xenograft in nude mice were sonicated by FUS using sub-threshold doses. The temperature at the focus was controlled at below 60 °C. The cell apoptosis in vitro was tested by flow cytometer at 3, 6, 12, 24 and 48 h after FUS sonication. Colony formation was used to evaluate the cell growth inhibition of FUS in vitro. The tumor volume of the xenograft was measured before and after FUS sonication. Then the slides of the tumor were under hematoxylin–eosin (H and E) staining and TdT-mediated dUTP nick end labeling (TUNEL) to evaluate the effect of FUS on pancreatic carcinoma xenograft in vivo. Results: The maximum cell suspension temperature of the FUS sonication group was 55.8 ± 2.17 °C. The cell apoptosis rate peaked at 24 h after FUS sonication, the differences between the FUS sonication group and control group were statistically significant (P 3 and 1085.23 ± 217.13 mm3 (P < 0.05). H and E staining and TUNEL assay showed both necrotic and apoptotic cells. Conclusion: Sub-threshold FUS sonication could induce cell apoptosis and inhibit the proliferation of pancreatic cancer cells.

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

    NARCIS (Netherlands)

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

    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 us

  4. Treatment time reduction through parameter optimization in magnetic resonance guided high intensity focused ultrasound treatments

    Science.gov (United States)

    Coon, Joshua

    Magnetic Resonance guided High Intensity Focused Ultrasound (MRgHIFU) treatments are a promising modality for cancer treatments in which a focused beam of ultrasound energy is used to kill tumor tissue. However, obstacles still exist to its widespread clinical implementation, including long treatment times. This research demonstrates reductions in treatment times through intelligent selection of the user-controllable parameters, including: the focal zone treatment path, focal zone size, focal zone spacing, and whether to treat one or several focal zone locations at any given time. Several treatments using various combinations of these parameters were simulated using a finite difference method to solve the Pennes bio-heat transfer equation for an ultrasonically heated tissue region with a wide range of acoustic, thermal, geometric, and tumor properties. The total treatment time was iteratively optimized using either a heuristic method or routines included in the Matlab software package, with constraints imposed for patient safety and treatment efficacy. The results demonstrate that large reductions in treatment time are possible through the intelligent selection of user-controllable treatment parameters. For the treatment path, treatment times are reduced by as much as an order of magnitude if the focal zones are arranged into stacks along the axial direction and a middle-front-back ordering is followed. For situations where normal tissue heating constraints are less stringent, these focal zones should have high levels of adjacency to further decrease treatment times; however, adjacency should be reduced in some cases where normal tissue constraints are more stringent. Also, the use of smaller, more concentrated focal zones produces shorter treatment times than larger, more diluted focal zones, a result verified in an agar phantom model. Further, focal zones should be packed using only a small amount of overlap in the axial direction and with a small gap in the

  5. Heating of tissues in vivo by pulsed focused ultrasound to stimulate enhanced HSP expression

    Science.gov (United States)

    Kujawska, Tamara; Wójcik, Janusz; Nowicki, Andrzej

    2011-09-01

    The main aim of this work was numerical modeling of temperature fields induced in soft tissues in vivo by pulsed focused ultrasound during neurodegenerative disease treatment and experimental verification of the proposed model for a rat liver. The new therapeutic approach to neurodegenerative diseases consists of stimulation of enhanced expression of the Heat Shock Proteins (HSP) which are responsible for immunity of cells to stress. During therapy the temperature rise in tissues in vivo should not exceed 6 °C above level of the thermal norm (37 °C). First, the 3D acoustic pressure field, and the rate of heat production per unit volume due to that field, were calculated using our 3D numerical solver capable of predicting nonlinear propagation of pulsed high intensity waves generated from circular focused acoustic sources in multilayer configuration of attenuating media. The two-layer configuration of media (water—rat liver) assumed in calculations fairly well approximated both the real anatomic dimensions of rat liver and the geometric scheme of our experimental set-up. A numerical solution of the Pennes bio-heat transfer equation which accounted for the effects of heat diffusion, blood perfusion and metabolism rates, was employed to calculate the temperature fields induced in the rat liver by the ultrasonic beam. The numerical simulation results were verified experimentally using a thermocouple inserted in the liver of a rat under anesthesia at the beam focus. The quantitative analysis of the obtained results enabled estimation of the effects of several acoustic and thermal parameters of the rat liver in vivo on the temperature rise, as well as determination of exposure time for ultrasonic beams with varied acoustic power generated by a 2-MHz circular transducer of 15-mm diameter and 25-mm focal length, in order to avoid the tissue overheating that leads to cells necrosis, which would be unacceptable in neurodegenerative disease treatment.

  6. Efficient low-beta H-mode accelerating structures with PMQ focusing

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory

    2008-01-01

    We are developing high-efficiency room-temperature RF accelerating structures for beam velocities in the range of a few percent of the speed of light by merging two well-known ideas: H-mode cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ). Combining electromagnetic 3-D modeling with beam dynamics simulations and thermal-stress analysis, we have found that the H-mode structures with PMQ focusing provide a very efficient and practical accelerator for light-ion beams of considerable currents. Such accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications such as a compact deuteron-beam accelerator up to the energy of a few MeV.

  7. Non-thermal ablation of rabbit liver VX2 tumor by pulsed high intensity focused ultrasound with ultrasound contrast agent: Pathological characteristics

    Institute of Scientific and Technical Information of China (English)

    Cheng-Wen Zhou; Fa-Qi Li; Yan Qin; Chun-Mei Liu; Xiao-Lin Zheng; Zhi-Biao Wang

    2008-01-01

    AIM:To investigate the pathological characteristics of non-thermal damage induced by pulsed high intensity focused ultrasound (PHIFU) combined with ultrasound contrast agent (UCA),SonoVue (Bracco SpA,Milan,Italy) in rabbit liver VX2 tumor.METHODS:Liver VX2 tumor models were established in 20 rabbits,which were divided randomly into PHIFU combined with ultrasound contrast agent group (PHIFU + UCA group) and sham group.In the PHIFU + UCA group,0.2 mL of SonoVue was injected intravenously into the tumor,followed by ultrasound exposure of Isp 5900 W/cm2.The rabbits were sacrificed one day after ultrasound exposure.Specimens of the exposed tumor tissues were obtained and observed pathologically under light microscope and transmission electron microscope.The remaining tumor tissues were sent for 2,3,5-Triphenyltetrazolium chloride (TTC) staining.RESULTS:Before TTC staining,tumor tissues in both the sham and the PHIFU + UCA groups resembled gray fish meat.After TTC staining,the tumor tissues were uniformly stained red,with a clear boundary between tumor tissue and normal tissue.Histological examination showed signs of tumor cell injury in PHIFU + UCA group,with cytoplasmic vacuoles of various sizes,chromatin margination and karyopyknosis.Electron microscopic examination revealed tumor cell volume reduction,karyopyknosis,chromatin margination,intercellular space widening,the presence of high electron-density apoptotic bodies and vacuoles in cytoplasm.CONCLUSION:The non-thermal effects of PHIFU combined with UCA can be used to ablate rabbit liver VX2 tumors.

  8. H-mode accelerating structures with PMQ focusing for low-beta ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, Sergey S [Los Alamos National Laboratory; O' Hara, James F [Los Alamos National Laboratory; Olivas, Eric R [Los Alamos National Laboratory; Rybarcyk, Lawrence J [Los Alamos National Laboratory

    2010-01-01

    We are developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. Such IH-PMQ accelerating structures following a short RFQ can be used in the front end of ion linacs or in stand-alone applications, e.g. a compact deuteron-beam accelerator up to the energy of several MeV. Results of combined 3-D modeling for a full IH-PMQ accelerator tank - electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis - are presented. The accelerating field profile in the tank is tuned to provide the best beam propagation using coupled iterations of electromagnetic and beam-dynamics modeling. A cold model of the IH-PMQ tank is being manufactured.

  9. 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.)

  10. Feasibility study on photoacoustic guidance for high-intensity focused ultrasound-induced hemostasis

    Science.gov (United States)

    Nguyen, Van Phuc; Kim, Jeehyun; Ha, Kang-lyeol; Oh, Junghwan; Kang, Hyun Wook

    2014-10-01

    The feasibility of photoacoustic imaging (PAI) application was evaluated to map punctured blood vessels thermally treated by high-intensity focused ultrasound (HIFU) for hemostasis. A single-element HIFU transducer with a central frequency of 2.0 MHz, was used to induce thermal hemostasis on the punctured arteries. The HIFU-treated lesion was imaged and localized by high-contrast PAI guidance. The results showed that complete hemostasis was achieved after treatment of the damaged blood vessels within 25 to 52 s at the acoustic intensity of 3600 W/cm2. The coagulation time for the animal artery was ˜20% longer than that of the phantom possibly due to a lower Young's modulus. The reconstructed PA images were able to distinguish the treated area from the surrounding tissue in terms of augmented signal amplitudes (up to three times). Spectroscopic studies demonstrated that the optimal imaging wavelength was found to be 700 nm in order to reconstruct high-contrast photoacoustic images on HIFU-treated lesions. The proposed PAI integrated with HIFU treatment can be a feasible application to obtain safe and rapid hemostasis for acute arterial bleeding.

  11. PATHOMORPHISM OF PROSTATE CANCER DURING HIGH-INTENSITY FOCUSED ULTRASOUND TREATMENT

    Directory of Open Access Journals (Sweden)

    R. N. Fomkin

    2014-07-01

    Full Text Available The purpose of the study was to evaluate the efficiency of prostate cancer (PC treatment using high-intensity focused ultrasound (HIFU on the basis of morphometric and immunohistochemical (IHC analyses of postoperative prostate biopsy specimens. The study subjects were 40 patients with localized and locally advanced PC. The postoperative morphological analysis was made on the basis of standard hematoxylineosin staining and morphometric and IHC studies using the following antibodies: PCNA, Bcl-2, AMACR, Е-cadherin, and ANDR (Dako. Pre- and post-HIFU therapy histological examination of the routinely hematoxylin-eosin-stained specimens showed that the therapeutic pathomorphism of the tumor corresponded to grades III and IV. It was established that the IHC study should be used as an additional crite-rion for the efficiency of PC therapy after HIFU ablation. In spite of positive clinical, laboratory, instrumental, and objective changes, the patients with high AMACR and Bcl-2 levels and decreased Е-cadherin expression may be considered as a group at risk for prolonged malignant growth or recurrent PC.

  12. Analgesic effect of high intensity focused ultrasound in patients with advanced pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Xinjin Tan; Jian Chen; Li Ren; Ruilu Lin; Zailian Chen

    2013-01-01

    Objective:The aim of this study was to evaluate the analgesic ef ect of high intensity focused ultrasound (HIFU) in patients with advanced pancreatic cancer. Methods:A total of 106 patients with advanced pancreatic cancer accompanied by abdominal pain were treated by HIFU. Pain intensities and quantities of morphine consumption before and after treatment were observed and compared. Results:The average pain intensities before treatment, and at d3, d7 after treatment were 5.80 ± 2.14, 2.73 ± 2.68, 2.45 ± 2.43 respectively (P<0.01). Fifty-nine cases (55.7%) got to extremely ef ective, and 29 cases (27.4%) ef ective. Total ef icient rate was 83.0%. The average quantities of morphine consumption before and after treatment in the patients with grade III pain were 114.9 ± 132.5 mg, 16.8 ± 39.7 mg each person everyday respectively (P<0.01). Conclusion:HIFU can relieve pain suf ered by patients with pancreatic cancer ef ectively. It is a new adjuvant treatment for pancreatic cancer pain.

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

    International Nuclear Information System (INIS)

    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.)

  14. Volumetric feedback ablation of uterine fibroids using magnetic resonance-guided high intensity focused ultrasound therapy

    Energy Technology Data Exchange (ETDEWEB)

    Voogt, M.J.; Mali, W.P.T.M.; Bosch, Maurice A.A.J. van den [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Trillaud, H.; Frulio, N. [Hospital St. Andre, Department of Radiology, Bordeaux (France); Kim, Y.S.; Rhim, H.; Lim, H.K. [Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Barkhausen, J.; Eckey, T. [University Hospital Schleswig-Holstein, Department of Radiology, Luebeck (Germany); Bartels, L.W.; Deckers, R. [University Medical Center Utrecht, Image Sciences Institute, Utrecht (Netherlands); Nieminen, H.J.; Soini, J.; Vaara, T.; Koehler, M.O. [Philips Healthcare, Vantaa (Finland); Mougenot, C. [Philips Healthcare, Toronto (Canada); Keserci, B. [Philips Healthcare, Seoul (Korea, Republic of); Sokka, S. [Philips Healthcare, Andover, MA (United States)

    2012-02-15

    The purpose of this prospective multicenter study was to assess the safety and technical feasibility of volumetric Magnetic Resonance-guided High Intensity Focused Ultrasound (MR-HIFU) ablation for treatment of patients with symptomatic uterine fibroids. Thirty-three patients with 36 fibroids were treated with volumetric MR-HIFU ablation. Treatment capability and technical feasibility were assessed by comparison of the Non-Perfused Volumes (NPVs) with MR thermal dose predicted treatment volumes. Safety was determined by evaluation of complications or adverse events and unintended lesions. Secondary endpoints were pain and discomfort scores, recovery time and length of hospital stay. The mean NPV calculated as a percentage of the total fibroid volume was 21.7%. Correlation between the predicted treatment volumes and NPVs was found to be very strong, with a correlation coefficient r of 0.87. All patients tolerated the treatment well and were treated on an outpatient basis. No serious adverse events were reported and recovery time to normal activities was 2.3 {+-} 1.8 days. This prospective multicenter study proved that volumetric MR-HIFU is safe and technically feasible for the treatment of symptomatic uterine fibroids. (orig.)

  15. Focused ultrasound-enhanced intranasal brain delivery of brain-derived neurotrophic factor

    Science.gov (United States)

    Chen, Hong; Yang, Georgiana Zong Xin; Getachew, Hoheteberhan; Acosta, Camilo; Sierra Sánchez, Carlos; Konofagou, Elisa E.

    2016-06-01

    The objective of this study was to unveil the potential mechanism of focused ultrasound (FUS)-enhanced intranasal (IN) brain drug delivery and assess its feasibility in the delivery of therapeutic molecules. Delivery outcomes of fluorescently-labeled dextrans to mouse brains by IN administration either before or after FUS sonication were compared to evaluate whether FUS enhances IN delivery by active pumping or passive diffusion. Fluorescence imaging of brain slices found that IN administration followed by FUS sonication achieved significantly higher delivery than IN administration only, while pre-treatment by FUS sonication followed by IN administration was not significantly different from IN administration only. Brain-derived neurotrophic factor (BDNF), a promising neurotrophic factor for the treatment of many central nervous system diseases, was delivered by IN followed by FUS to demonstrate the feasibility of this technique and compared with the established FUS technique where drugs are injected intravenously. Immunohistochemistry staining of BDNF revealed that FUS-enhanced IN delivery achieved similar locally enhanced delivery as the established FUS technique. This study suggested that FUS enhances IN brain drug delivery by FUS-induced active pumping of the drug and demonstrated that FUS-enhanced IN delivery is a promising technique for noninvasive and localized delivery of therapeutic molecules to the brain.

  16. Focused ultrasound-mediated sonochemical internalization: an alternative to light-based therapies

    Science.gov (United States)

    Gonzales, Jonathan; Nair, Rohit Kumar; Madsen, Steen J.; Krasieva, Tatiana; Hirschberg, Henry

    2016-07-01

    Activation of sonosensitizers via focused ultrasound (FUS), i.e., sonodynamic therapy has been proposed as an extension to light-activated photodynamic therapy for the treatment of brain as well as other tumors. The use of FUS, as opposed to light, allows treatment to tumor sites buried deep within tissues as well as through the intact skull. We have examined ultrasonic activation of sonosensitizers together with the anticancer agent bleomycin (BLM), i.e., sonochemical internalization (SCI). SCI is a technique that utilizes FUS for the enhanced delivery of endo-lysosomal trapped macromolecules into the cell cytoplasm in a similar manner to light-based photochemical internalization. The released agent can, therefore, exert its full biological activity, in contrast to being degraded by lysosomal hydrolases. Our results indicate that, compared to drug or FUS treatment alone, FUS activation of the sonosensitizer AlPcS2a together with BLM significantly inhibits the ability of treated glioma cells to grow as three-dimensional tumor spheroids in vitro.

  17. 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.

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

    International Nuclear Information System (INIS)

    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

  19. Keratorefractive Effect of High Intensity Focused Ultrasound Keratoplasty on Rabbit Eyes

    Directory of Open Access Journals (Sweden)

    Zhiyu Du

    2016-01-01

    Full Text Available Purpose. To evaluate high intensity focused ultrasound (HIFU as an innovation and noninvasive technique to correct presbyopia by altering corneal curvature in the rabbit eye. Methods. Eighteen enucleated rabbit eyes were treated with a prototype HIFU keratoplasty. According to the therapy power, these eyes were divided three groups: group 1 (1 W, group 2 (2 W, and group 3 (3 W. The change in corneal power was quantified by a Sirius Scheimpflug camera. Light microscopy (LM and transmission electron microscopy (TEM were performed to determine the effect on the corneal stroma. Results. In the treated eyes, the corneal curvature increases from 49.42 ± 0.30 diopters (D and 48.00 ± 1.95 D before procedure to 51.37 ± 1.11 D and 57.00 ± 1.84 D after HIFU keratoplasty application in groups 1 and 3, respectively. The major axis and minor axis of the focal region got longer when the powers of the HIFU got increased; the difference was statistically significant (p<0.05. LM and TEM showed HIFU-induced shrinkage of corneal stromal collagen with little disturbance to the underlying epithelium. Conclusions. We have preliminarily exploited HIFU to establish a new technique for correcting presbyopia. HIFU keratoplasty will be a good application prospect for treating presbyopia.

  20. Treatment of murine tumors using acoustic droplet vaporization-enhanced high intensity focused ultrasound

    Science.gov (United States)

    Zhu, Meili; Jiang, Lixing; Fabiilli, Mario L.; Zhang, Aili; Fowlkes, J. Brian; Xu, Lisa X.

    2013-09-01

    High intensity focused ultrasound (HIFU) can be applied focally and noninvasively to thermally ablate solid tumors. Long treatment times are typically required for large tumors, which can expose patients to certain risks while potentially decreasing the therapeutic efficacy of the treatment. Acoustic droplet vaporization (ADV) is a promising modality that can enhance the efficacy of tumor treatment using HIFU. In this study, the therapeutic effects of combined HIFU and ADV was evaluated in mice bearing subcutaneously-implanted 4T1 tumors. Histological examination showed that the combination of HIFU and ADV generated a mean necrotic area in the tumor that was 2.9-fold larger than with HIFU alone. A significant enhancement of necrosis was found in the periphery of the tumor, where the blood supply was abundant. Seven days after treatment, the tumors treated with combined HIFU and ADV were 30-fold smaller in volume than tumors treated with HIFU alone. The study demonstrates the potential advantage of combining HIFU and ADV in tumor treatment.

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

    International Nuclear Information System (INIS)

    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 T2 increases linearly in fat during heating. T2-mapping using dual echo times during a dynamic turbo spin-echo pulse sequence enabled rapid measurement of T2. Calibration of T2-based thermal maps involved heating the marrow in a bovine femur and simultaneously measuring T2 and temperature with a thermocouple. A positive T2 temperature dependence in bone marrow of 20 ms/°C was observed. Dynamic T2-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.

  2. Image-based control of the magnetic resonance imaging-guided focused ultrasound thermotherapy.

    Science.gov (United States)

    Salomir, Rares; Delemazure, Anne-Sophie; Palussière, Jean; Rouvière, Olivier; Cotton, François; Chapelon, Jean-Yves

    2006-06-01

    Magnetic resonance imaging (MRI)-guided focused ultrasound surgery (FUS) is a full noninvasive approach for localized thermal ablation of deep tissues, coupling the following: (1) a versatile, nonionizing physical agent for therapy and (2) a state-of-the art diagnosis and on-line monitoring tool. A commercially available, Food and Drug Administration-approved device using the MRI-guided FUS exists since 2004 for the ablation of benign tumors (uterine fibroids); however, the ultimate goal of the technological, methodological, and medical research in this field is to provide a clinical-routine tool for fighting localized cancer. When addressing cancer applications, the accurate spatial control of the delivered thermal dose is mandatory. Contiguous destruction of the target volume must be achieved in a minimum time, whereas sparing as much as possible the neighboring healthy tissues and especially when some adjacent regions are critical. This paper reviews some significant developments reported in the literature related to the image-based control of the FUS therapy for kidney, breast, prostate, and brain, including the own experience of the authors on the active feedback control of the temperature during FUS ablation. In addition, preliminary results of an original study of MRI-guided FUS ablation of VX2 carcinoma in kidney, under active temperature control, are described here.

  3. High-Intensity Focused Ultrasound for Prostate Cancer: Long-Term Followup and Complications Rate

    Directory of Open Access Journals (Sweden)

    Umberto Maestroni

    2012-01-01

    Full Text Available Introduction. As it is well known, High Intensity Focused Ultrasound (HIFU is a minimally invasive procedure for prostate cancer. Many investigators reported their series of patients, demonstrating the effectiveness of the treatment. The most majority of Authors, however, do not report the side effects and the complications of the procedure, which is the aim of our study. The diagnosis and management of complications is discussed, and the oncologic outcome is reported in terms of quality of life. Materials and Methods. We report our experience in 89 patients, low-, intermediate-, and high-risk patients according with D’Amico classification. All data collected along the study were analyzed, including side effects and complications of the procedure. Results. Our series demonstrates the effectiveness of the procedure, in line with larger series reported in literature by other investigators. The most important side effects are sexual function impairment and transient incontinence in a minority of cases. Minor complications are reported as well as rare cases of major complications, which can require surgical treatment.

  4. Salvage High-intensity Focused Ultrasound for the Recurrent Prostate Cancer after Radiotherapy

    Science.gov (United States)

    Shoji, S.; Nakano, M.; Omata, T.; Harano, Y.; Nagata, Y.; Usui, Y.; Terachi, T.; Uchida, T.

    2010-03-01

    To investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 20 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and September 1, 2009, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. All men with presumed, organ-confined, recurrent disease following EBRT in 8 patients, brachytherapy in 7 patients or proton therapy in 5 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 16.0 (3-80) months. Biochemical disease-free survival (bDFS) rates in patients with low-intermediate and high risk groups were 86% and 50%, respectively. Side-effects included urethral stricture in 2 of the 16 patients (13%), urinary tract infection or dysuria syndrome in eight (26%), and urinary incontinence in one (6%). Recto-urethral fistula occurred in one patient (6%). Transrectal HIFU is an effective treatment for recurrence after radiotherapy especially in patients with low- and intermediate risk groups.

  5. PATHOMORPHISM OF PROSTATE CANCER DURING HIGH-INTENSITY FOCUSED ULTRASOUND TREATMENT

    Directory of Open Access Journals (Sweden)

    R. N. Fomkin

    2013-01-01

    Full Text Available The purpose of the study was to evaluate the efficiency of prostate cancer (PC treatment using high-intensity focused ultrasound (HIFU on the basis of morphometric and immunohistochemical (IHC analyses of postoperative prostate biopsy specimens. The study subjects were 40 patients with localized and locally advanced PC. The postoperative morphological analysis was made on the basis of standard hematoxylineosin staining and morphometric and IHC studies using the following antibodies: PCNA, Bcl-2, AMACR, Е-cadherin, and ANDR (Dako. Pre- and post-HIFU therapy histological examination of the routinely hematoxylin-eosin-stained specimens showed that the therapeutic pathomorphism of the tumor corresponded to grades III and IV. It was established that the IHC study should be used as an additional crite-rion for the efficiency of PC therapy after HIFU ablation. In spite of positive clinical, laboratory, instrumental, and objective changes, the patients with high AMACR and Bcl-2 levels and decreased Е-cadherin expression may be considered as a group at risk for prolonged malignant growth or recurrent PC.

  6. Urodynamic Evaluation after High-Intensity Focused Ultrasound for Patients with Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Luigi Mearini

    2014-01-01

    Full Text Available This prospective study assesses the impact of high-intensity focused ultrasound (HIFU on lower urinary tract by comparing pre- and postoperative symptoms and urodynamic changes. Thirty consecutive patients with clinically organ-confined prostate cancer underwent urodynamic study before HIFU and then at 3–6 months after surgery. Continence status and symptoms were analyzed by means of International Prostate Symptoms Score IPSS and International Index Erectile Function IIEF5. As a result, there were a significant improvement in bladder outlet, maximum flow at uroflowmetry, and reduction in postvoid residual PVR at 6-month follow-up and a concomitant significant reduction of detrusor pressure at opening and at maximum flow. De novo overactive bladder and impaired bladder compliance were detected in 10% of patients at 3 months, with progressive improvement at longer follow-up. Baseline prostate volume and length of the procedure were predictors of 6-month IPSS score and continence status. In conclusion, following HIFU detrusor overactivity, decreased bladder compliance and urge incontinence represent de novo dysfunction due to prostate and bladder neck injury during surgery. However, urodynamic study shows a progressive improvement in all storage and voiding patterns at 6-month follow-up. Patients with high prostate volume and long procedure length suffered from irritative symptoms even at long term.

  7. High-Intensity Focused Ultrasound (HIFU) for the Treatment of Localized Prostate Cancer using Sonablate-500

    Science.gov (United States)

    Uchida, Toyoaki; Ohkusa, Hiroshi; Yamashita, Hideyuki; Nagata, Yoshihiro

    2005-03-01

    We evaluated 181 patients with localized prostate cancer treated with high-intensity focused ultrasound (HIFU) for biochemical disease-free rate, safety, morbidity and predictors of biochemical outcome. A total of 181 patients underwent HIFU with the Sonablate-500 and with at least 12 months of follow-up. Biochemical failure was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The biochemical disease-free rates at 1, 3 and 5 years in all patients were 84%, 80% and 78%, respectively. The biochemical disease-free rates at 3 years for patients with pretreatment PSA less than 10 ng/ml, 10.01 to 20.0 ng/ml and more than 20.0 ng/ml were 94%, 75% and 35%, respectively (pHIFU therapy appears to be a safe and efficacious minimally invasive therapy for patients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/ml.

  8. Usage of Magnetic Resonance Guided Focused Ultrasound Surgery (mrgfus) in Oncology

    Science.gov (United States)

    Bauer, Yair

    2011-09-01

    Magnetic resonance guided focused ultrasound surgery (MRgFUS) is a non-invasive incision-less surgical approach which limits the tissue destruction to the targeted tumor. Acoustic energy penetrates through intact skin and through the tissues surrounding the tumor without causing any significant bio-effects. Energy deposition takes place mainly at the focal spot where heat induced thermal coagulation of the targeted tissue is accomplished. Real time targeting and image guidance is provided by MRI tumor margin definition and real time thermometry provides closed loop feedback control of energy deposition. The patient lies in the MRI scanner throughout the treatment planning and treatment, and the physician conducts the treatment from the MRgFUS workstation in the adjacent MR control room. The ExAblate system for MRgFUS is commercially available in many countries for treatment of uterine fibroids. The system has also received CE and KFDA approval for pain palliation of bone metastases, and research of other oncologic applications is underway.

  9. Acoustic power measurement of high-intensity focused ultrasound transducer using a pressure sensor.

    Science.gov (United States)

    Zhou, Yufeng

    2015-03-01

    The acoustic power of high-intensity focused ultrasound (HIFU) is an important parameter that should be measured prior to each treatment to guarantee effective and safe outcomes. A new calibration technique was developed that involves estimating the pressure distribution, calculating the acoustic power using an underwater pressure blast sensor, and compensating the contribution of harmonics to the acoustic power. The output of a clinical extracorporeal HIFU system (center frequency of ~1 MHz, p+ = 2.5-57.2 MPa, p(-) = -1.8 to -13.9 MPa, I(SPPA) = 513-22,940 W/cm(2), -6 dB size of 1.6 × 10 mm: lateral × axial) was measured using this approach and then compared with that obtained using a radiation force balance. Similarities were found between each method at acoustic power ranging from 18.2 W to 912 W with an electrical-to-acoustic conversion efficiency of ~42%. The proposed method has advantages of low weight, smaller size, high sensitivity, quick response, high signal-to-noise ratio (especially at low power output), robust performance, and easy operation of HIFU exposimetry measurement.

  10. Three Dimensional Motion Compensation for Real-Time MRI Guided Focused Ultrasound Treatment of Abdominal Organs

    Science.gov (United States)

    Ries, M.; De Senneville, B. D.; Roujol, S.; Hey, S.; Maclair, G.; Köhler, M. O.; Quesson, B.; Moonen, C. T. W.

    2010-03-01

    MR-guided high intensity focused ultrasound (HIFU) has evolved into a promising non-invasive technique for the ablation of pathological tissue in abdominal organs. However, since the high perfusion rates of these organs lead to effective cooling, sustained sonications of 30-90 s are required to achieve a sufficiently high temperature elevation to induce necrosis. This is complicated by the constant displacement of the target due to the respiratory cycle. This study proposes sub-second 3D HIFU-beam steering under MR-guidance for the near real-time compensation of respiratory motion as a possible solution. The target position is observed in 3D space by coupling rapid 2D MR-imaging with prospective slice tracking (PST) based on pencil-beam navigator echoes. Continuous real-time image processing provides temperature maps, thermal dose estimates and the target position at a frequency of 10 Hz and an update latency of less than 120 ms. The suggested method is evaluated with phantom experiments and its feasibility is verified in-vivo with an ablation experiment on a porcine kidney where it allows to achieve a thermal energy deposition which is comparable to static control experiments.

  11. Safety Validation of Repeated Blood-Brain Barrier Disruption Using Focused Ultrasound.

    Science.gov (United States)

    Kobus, Thiele; Vykhodtseva, Natalia; Pilatou, Magdalini; Zhang, Yongzhi; McDannold, Nathan

    2016-02-01

    The purpose of this study was to investigate the effects on the brain of multiple sessions of blood-brain barrier (BBB) disruption using focused ultrasound (FUS) in combination with micro-bubbles over a range of acoustic exposure levels. Six weekly sessions of FUS, using acoustical pressures between 0.66 and 0.80 MPa, were performed under magnetic resonance guidance. The success and degree of BBB disruption was estimated by signal enhancement of post-contrast T1-weighted imaging of the treated area. Histopathological analysis was performed after the last treatment. The consequences of repeated BBB disruption varied from no indications of vascular damage to signs of micro-hemorrhages, macrophage infiltration, micro-scar formations and cystic cavities. The signal enhancement on the contrast-enhanced T1-weighted imaging had limited value for predicting small-vessel damage. T2-weighted imaging corresponded well with the effects on histopathology and could be used to study treatment effects over time. This study demonstrates that repeated BBB disruption by FUS can be performed with no or limited damage to the brain tissue.

  12. Complications of high intensity focused ultrasound in patients with recurrent and metastatic abdominal tumors

    Institute of Scientific and Technical Information of China (English)

    Jian-Jun Li; Guo-Liang Xu; Mo-Fa Gu; Guang-Yu Luo; Zhang Rong; Pei-Hong Wu; Jian-Chuan Xia

    2007-01-01

    AIM: To analyze the local and systemic complications of high intensity focused ultrasound (HIFU) for patients with recurrent and metastatic abdominal tumors.METHODS: From Aug 2001 to Aug 2004, 17 patients with recurrent and metastatic abdominal tumors were enrolled in this study. Real-time sonography was taken, and vital signs, liver and kidney function, skin burns, local reactions, and systemic effects were observed and recored before, during, and after HIFU. CT and MRI were also taken before and after HIFU.RESULTS: All 17 patients had skin burns and pAln in the treatment region; the next common complication was neurapraxia of the stomach and intestines to variable degrees. The other local and systemic complications were relatively rare. Severe complications were present in two patients; one developed a superior mesenteric artery infarction resulting in necrosis of the entire small intestines, and the other one suffered from a perforation in terminal ileum due to HIFU treatment.CONCLUSION: Although HIFU is a one of noninvasive treatments for the recurrent and metastatic abdominal tumors, there are still some common and severe complications which need serious consideration.

  13. Optimization of Focused Ultrasound and Image Based Modeling in Image Guided Interventions

    Science.gov (United States)

    Almekkawy, Mohamed Khaled Ibrahim

    Image-guided high intensity focused ultrasound (HIFU) is becoming increasingly accepted as a form of noninvasive ablative therapy for the treatment of prostate cancer, uterine fibroids and other tissue abnormalities. In principle, HIFU beams can be focused within small volumes which results in forming precise lesions within the target volume (e.g. tumor, atherosclerotic plaque) while sparing the intervening tissue. With this precision, HIFU offers the promise of noninvasive tumor therapy. The goal of this thesis is to develop an image-guidance mode with an interactive image-based computational modeling of tissue response to HIFU. This model could be used in treatment planning and post-treatment retrospective evaluation of treatment outcome(s). Within the context of treatment planning, the challenge of using HIFU to target tumors in organs partially obscured by the rib cage are addressed. Ribs distort HIFU beams in a manner that reduces the focusing gain at the target (tumor) and could cause a treatment-limiting collateral damage. We present a refocusing algorithms to efficiently steer higher power towards the target while limiting power deposition on the ribs, improving the safety and efficacy of tumor ablation. Our approach is based on an approximation of a non-convex to a convex optimization known as the semidefinite relaxation (SDR) technique. An important advantage of the SDR method over previously proposed optimization methods is the explicit control of the sidelobes in the focal plane. A finite-difference time domain (FDTD) heterogeneous propagation model of a 1-MHz concave phased array was used to model the acoustic propagation and temperature simulations in different tissues including ribs. The numerical methods developed for the refocusing problem are also used for retrospective analysis of targeting of atherosclerotic plaques using HIFU. Cases were simulated where seven adjacent HIFU shots (5000 W/cm2, 2 sec exposure time) were focused at the plaque

  14. 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

  15. Computational Complexity Reduction of Synthetic-aperture Focus in Ultrasound Imaging Using Frequency-domain Reconstruction.

    Science.gov (United States)

    Moghimirad, Elahe; Mahloojifar, Ali; Mohammadzadeh Asl, Babak

    2016-05-01

    A new frequency-domain implementation of a synthetic aperture focusing technique is presented in the paper. The concept is based on synthetic aperture radar (SAR) and sonar that is a developed version of the convolution model in the frequency domain. Compared with conventional line-by-line imaging, synthetic aperture imaging has a better resolution and contrast at the cost of more computational load. To overcome this problem, point-by-point reconstruction methods have been replaced by block-processing algorithms in radar and sonar; however, these techniques are relatively unknown in medical imaging. In this paper, we extended one of these methods called wavenumber to medical ultrasound imaging using a simple model of synthetic aperture focus. The model, derived here for monostatic mode, can be generalized to multistatic as well. The method consists of 4 steps: a 2D fast Fourier transform of the data, frequency shift of the data to baseband, interpolation to convert polar coordinates to rectangular ones, and returning the data to the spatial-domain using a 2D inverse Fourier transform. We have also used chirp pulse excitation followed by matched filtering and spotlighting algorithm to compensate the effect of differences in parameters between radar and medical imaging. Computational complexities of the two methods, wavenumber and delay-and-sum (DAS), have been calculated. Field II simulated point data have been used to evaluate the results in terms of resolution and contrast. Evaluations with simulated data show that for typical phantoms, reconstruction by the wavenumber algorithm is almost 20 times faster than classical DAS while retaining the resolution. PMID:25900969

  16. Enhanced high intensity focused ultrasound heat deposition for more efficient hemostasis

    Science.gov (United States)

    Labuda, Cecille Pemberton

    High intensity focused ultrasound (HIFU) is currently being developed for hemorrhage control since it provides rapid energy deposition in the form of heat in the HIFU focal region. When the HIFU focus is targeted on soft tissue wounds, the resulting elevation of tissue temperature cauterizes the tissues thus stopping the bleeding. If HIFU is targeted near blood vessels with millimeter-range diameter, the rate of heat deposition is limited by loss of heat to the blood flow. Maximizing the local heat deposition is important for the achievement of HIFU-induced hemorrhage control, or "hemostasis", near large vessels. In this study, the effect of a fiber device on the heat deposition in the HIFU focal region is investigated in tissue-mimicking flow phantoms with liquid albumen as the heat-sensitive denaturing flow fluid. The effect of the embedded fiber on albumen coagulation in the flow phantom is compared to the degree and rate of albumen coagulation when no fiber is present. The effect of the fiber device on the size of lesions formed in a heat-sensitive tissue-mimicking phantom is also investigated. Finally, finite difference time domain simulations are performed to determine the heat deposition in a tissue-mimicking phantom with a nylon disc embedded and a phantom with the nylon disc removed. The results of this study are quite promising for the possibility of increased efficacy of hemostasis for such a device in concert with HIFU in vessel-containing tissue volumes where HIFU alone is not completely effective.

  17. 76 FR 43119 - Medical Devices; General and Plastic Surgery Devices; Classification of the Focused Ultrasound...

    Science.gov (United States)

    2011-07-20

    ... producing either localized heating for tissue coagulation or for mechanical cellular membrane disruption... expose the eye to ultrasound radiation, as well as specific directions intended to ensure complete... localized heating for tissue coagulation or for mechanical cellular membrane disruption intended...

  18. Focusing characteristics of an accelerating structure with non-circular beam holes

    International Nuclear Information System (INIS)

    High energy linacs of the next generation are required to keep stably high bunch populations and very small beam spots at colliding points, in order to realize high luminosity at TeV energy region. CERN proposed to apply the rf focusing technology which makes a strong focusing force according to the rf phase within a bunch, and rf focusing power is proportional to both the accelerating gradient and the operating frequency. Some computed results of the focusing property of 3 GHz accelerating structures are presented which has non-circular beam holes. The construction of this 3 GHz structure, because an rf technology for 3 GHz is well-established, will be useful in order to know, at an early stage of the development, whether the idea will be successful or not. The 3D code MAFIA was used to investigate the deflecting force caused by the asymmetry of the beam aperture. (R.P.) 5 refs., 14 figs., 3 tabs

  19. Biomechanical assessment and monitoring of thermal ablation using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

    Science.gov (United States)

    Hou, Gary Yi

    Cancer remains, one of the major public health problems in the United States as well as many other countries worldwide. According to According to the World Health Organization, cancer is currently the leading cause of death worldwide, accounting for 7.6 million deaths annually, and 25% of the annual death was due to Cancer during the year of 2011. In the long history of the cancer treatment field, many treatment options have been established up to date. Traditional procedures include surgical procedures as well as systemic therapies such as biologic therapy, chemotherapy, hormone therapy, and radiation therapy. Nevertheless, side-effects are often associated with such procedures due to the systemic delivery across the entire body. Recently technologies have been focused on localized therapy under minimally or noninvasive procedure with imaging-guidance, such as cryoablation, laser ablation, radio-frequency (RF) ablation, and High Intensity F-ocused Ultrasound (HIFU). HIFU is a non-invasive procedure aims to coagulate tissue thermally at a localized focal zone created with noninvasively emitting a set of focused ultrasound beams while the surrounding healthy tissues remain relatively untreated. Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a dynamic, radiation-force-based imaging technique, which utilizes a single HIFU transducer by emitting an Amplitude-modulated (AM) beam to both thermally ablate the tumor while inducing a stable oscillatory tissue displacement at its focal zone. The oscillatory response is then estimated by a cross-correlation based motion tracking technique on the signal collected by a confocally-aligned diagnostic transducer. HMIFU addresses the most critical aspect and one of the major unmet needs of HIFU treatment, which is the ability to perform real-time monitoring and mapping of tissue property change during the HIFU treatment. In this dissertation, both the assessment and monitoring aspects of HMIFU have been investigated

  20. Contrast-enhanced ultrasound for evaluation of high-intensity focused ultrasound treatment of benign uterine diseases: retrospective analysis of contrast safety.

    Science.gov (United States)

    Cheng, Chong-Qing; Zhang, Rui-Tao; Xiong, Yu; Chen, Li; Wang, Jian; Huang, Guo-Hua; Li, Ke-Quan; Zhang, Lian; Bai, Jin

    2015-04-01

    As a noninvasive treatment technique, ultrasound-guided high-intensity focused ultrasound (HIFU) has been considered as a routine treatment for uterine fibroids and adenomyosis in China. Contrast-enhanced ultrasound (CEUS) has been proposed as another option to assess the treatment efficacy during HIFU treatment. The aim of this investigation is to evaluate the adverse effects of HIFU ablation for benign uterine diseases in a group of patients studied with ultrasound contrast agent (UCA), in comparison with a group of patients not exposed to UCA. From November 2010 to December 2013, 2604 patients with benign uterine diseases were treated with HIFU. Among them, 1300 patients were exposed to an UCA, whereas 1304 patients were not.During HIFU procedure, the incidences of leg pain, sacral/buttock pain, groin pain, treatment area pain, and the discomfort "hot" sensation on skin were higher in the patients who were exposed to SonoVue (Bracco, Milan, Italy) than those who were not (20.5% vs 11.7%, 52.5% vs 42.3%, 6.5% vs 4.5%, 68.9% vs 55.4%, and 48.1% vs 42.9%, respectively). Among the postoperative adverse effects, the incidence of lower abdominal pain was significantly higher in patients who were exposed to an UCA than those who were not (51.2% vs 39.9%, P < 0.05). Two patients who were exposed to an UCA had acute renal function failure.In conclusion, UCA may increase the incidences of some common HIFU-related adverse effects during HIFU treatment for benign uterine diseases, but most of which were acceptable and self-limited. After HIFU treatment, renal function should be monitored in patients with a history of hypertension or taking nonsteroidal anti-inflammatory drugs. PMID:25906100

  1. Collective focusing ion accelerator. Final technical report, July 1, 1981-June 30, 1984

    International Nuclear Information System (INIS)

    In the Collective Focusing Ion Accelerator, electrons are confined by an external magnetic field. The electrostatic field of the confined electrons form a Gabor lens which can guide and focus the ions. In a toroidal geometry, ions can be accelerated inductively as in a betatron, focused and held in their circular orbit by a series of Gabor lenses along the torus. The CFIA experiment consists of a glass torus 110 cm major diameter and 12 cm minor diameter. Sixteen magnetic mirror cells are distributed around the torus. Electrons are produced by 16 thermionic injectors (1 injector per cell). The electrons are trapped by a rising magnetic field and form the Gabor lenses. The inductive field was supplied in the CFIA by an iron core with approx.300 cm2 cross section which could accelerate protons to more than 1 MeV. In order to accelerate ions they must be held by the lenses. The electron cloud was investigated in great detail. Early work had shown that the electron cloud oscillates in the radial direction in the mirror cells. These oscillations are very damaging to the focusing quality of the lens. The off-centering and the wobbling of the electrons was studied both in linear and toroidal geometry. The influence of the injector position, voltage, current and other parameters were investigated

  2. Alternating-phase-focused IH-DTL for an injector of heavy-ion medical accelerators

    Science.gov (United States)

    Iwata, Y.; Yamada, S.; Murakami, T.; Fujimoto, T.; Fujisawa, T.; Ogawa, H.; Miyahara, N.; Yamamoto, K.; Hojo, S.; Sakamoto, Y.; Muramatsu, M.; Takeuchi, T.; Mitsumoto, T.; Tsutsui, H.; Watanabe, T.; Ueda, T.

    2006-12-01

    A compact Drift-Tube-Linac (DTL) using an Interdigital H-mode (IH) cavity was designed for an injector of medical accelerators. For beam focusing, the method of Alternating-Phase-Focusing (APF) was applied. The APF IH-DTL can accelerate heavy ions having a charge-to-mass ratio of q/m={1}/{3} up to 4.0 MeV/u. Having optimized an array of synchronous phases for cells, namely arranging drift tubes and gaps appropriately, both longitudinal and transverse focusing strengths were produced just with the rf acceleration field, and therefore no focusing element or cooling equipments had to be installed in the cavity. This allowed us to employ a rather high operating frequency, and hence to design a compact and cost-effective cavity. A further advantage of the APF linac can be found in its operation. Since the parameters to be adjusted are just the level and phase of the input rf, beam tuning can be made with ease. Consequently, the APF linac is suitable for an injector for medical accelerators. Tuning methods of the gap voltages and cavity frequency as well as the design of the cavity for APF IH-DTL have been developed. After constructing the cavity, measurements of the electric field and tuning of the gap voltages were performed. Finally, the rf power was fed into the cavity. In this paper, the design and results of the measurements are described.

  3. Modeling of high-intensity focused ultrasound-induced lesions in the presence of cavitation bubbles

    Science.gov (United States)

    Chavrier; Chapelon; Gelet; Cathignol

    2000-07-01

    The classical "Bio Heat Transfer Equation (BHTE)" model is adapted to take into account the effects of oscillating microbubbles that occur naturally in the tissue during high-intensity focused ultrasound (HIFU) treatment. First, the Gilmore-Akulichev model is used to quantify the acoustic pressure scattered by microbubbles submitted to HIFU. Because this scattered pressure is not monochromatic, the concept of harmonic attenuation is introduced and a global attenuation coefficient is estimated for bubble-filled tissues. The first results show that this global attenuation coefficient varies significantly with respect to several parameters such as the frequency and the density of microbubbles in the medium, but also with respect to the incident acoustic pressure which thus becomes a transcendental function. Under these conditions, a layer-by-layer modeling, in the direction of propagation, is proposed to calculate the ultrasonic beam. Finally, the BHTE is solved and the HIFU-induced lesions are estimated by the calculation of the thermal dose. Using this model, it can be observed first that, when the firing power increases, the lesion develops clearly in the direction of the transducer, with a shape agreeing with in vivo experimentation. Next, it is observed that the lesion can be significantly modified in size and position, if an interface (skin or inner wall) is simulated as a zone with multiple cavitation nuclei. With a firing power increase, it is also shown how a secondary lesion can appear at the interface and how, beyond a certain threshold, this lesion develops at the main lesion expense. Finally, a better in-depth homogeneity of lesions is observed when the acoustic frequency of HIFU is increased.

  4. A new brain drug delivery strategy: focused ultrasound-enhanced intranasal drug delivery.

    Science.gov (United States)

    Chen, Hong; Chen, Cherry C; Acosta, Camilo; Wu, Shih-Ying; Sun, Tao; Konofagou, Elisa E

    2014-01-01

    Central nervous system (CNS) diseases are difficult to treat because of the blood-brain barrier (BBB), which prevents most drugs from entering into the brain. Intranasal (i.n.) administration is a promising approach for drug delivery to the brain, bypassing the BBB; however, its application has been restricted to particularly potent substances and it does not offer localized delivery to specific brain sites. Focused ultrasound (FUS) in combination with microbubbles can deliver drugs to the brain at targeted locations. The present study proposed to combine these two different platform techniques (FUS+i.n.) for enhancing the delivery efficiency of intranasally administered drugs at a targeted location. After i.n. administration of 40 kDa fluorescently-labeled dextran as the model drug, FUS targeted at one region within the caudate putamen of mouse brains was applied in the presence of systemically administered microbubbles. To compare with the conventional FUS technique, in which intravenous (i.v.) drug injection is employed, FUS was also applied after i.v. injection of the same amount of dextran in another group of mice. Dextran delivery outcomes were evaluated using fluorescence imaging of brain slices. The results showed that FUS+i.n. enhanced drug delivery within the targeted region compared with that achieved by i.n. only. Despite the fact that the i.n. route has limited drug absorption across the nasal mucosa, the delivery efficiency of FUS+i.n. was not significantly different from that of FUS+i.v.. As a new drug delivery platform, the FUS+i.n. technique is potentially useful for treating CNS diseases.

  5. Effects of oxytocin on high intensity focused ultrasound (HIFU) ablation of adenomysis: A prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xin [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Zou, Min; Zhang, Cai [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); He, Jia [Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Mao, Shihua [Department of Obstetrics and Gynecology, Three Gorges Central Hospital, Chongqing 404000 (China); Wu, Qingrong [Department of Obstetrics and Gynecology, Fuling Central Hospital, Chongqing 408099 (China); He, Min [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Wang, Jian [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Three Gorges Central Hospital, Chongqing 404000 (China); Zhang, Ruitao [Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Fuling Central Hospital, Chongqing 408099 (China); Zhang, Lian, E-mail: lianwzhang@yahoo.com [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Department of Obstetrics and Gynecology, Chongqing Haifu Hospital, Chongqing 401121 (China)

    2014-09-15

    Objective: To investigate the effects of oxytocin on high-intensity focused ultrasound (HIFU) ablation for the treatment of adenomyosis. Materials and methods: Eighty-six patients with adenomyosis from three hospitals were randomly assigned to the oxytocin group or control group for HIFU treatment. During HIFU treatment, 80 units of oxytocin was added in 500 ml of 0.9% normal saline running at the rate of 2 ml/min (0.32 U/min) in the oxytocin group, while 0.9% normal saline was used in the control group. Both patients and HIFU operators were blinded to oxytocin or saline application. Treatment results, adverse effects were compared. Results: When using oxytocin, the non-perfused volume (NPV) ratio was 80.7 ± 11.6%, the energy-efficiency factor (EEF) was 8.1 ± 9.9 J/mm{sup 3}, and the sonication time required to ablate 1 cm{sup 3} was 30.0 ± 36.0 s/cm{sup 3}. When not using oxytocin, the non-perfused volume ratio was 70.8 ± 16.7%, the EEF was 15.8 ± 19.6 J/mm{sup 3}, and the sonication time required to ablate 1 cm{sup 3} was 58.2 ± 72.7 S/cm{sup 3}. Significant difference in the NPV ratio, EEF, and the sonication time required to ablate 1 cm{sup 3} between the two groups was observed. No oxytocin related adverse effects occurred. Conclusion: Oxytocin could significantly decrease the energy for ablating adenomyosis with HIFU, safely enhance the treatment efficiency.

  6. Reproducibility of Left Atrial Ablation with High Intensity Focused Ultrasound Energy in a Calf Model

    Science.gov (United States)

    Villamizar, Nestor R.; Crow, Jennifer H.; III, Valentino Piacentino; DiBernardo, Louis R.; Daneshmand, Mani A.; Bowles, Dawn E.; Groh, Mark A.; Milano, Carmelo A.

    2014-01-01

    Purpose Achieving transmural tissue ablation may be necessary for successful treatment of atrial fibrillation. The purpose of this study is to evaluate the reproducibility of transmural left atrial (LA) ablation using a high intensity focused ultrasound (HIFU) energy system in a calf model. Methods Nine heparinized bovines underwent a beating-heart LA ablation with a single application of the HIFU device. All animals were acutely sacrificed and the LA was fixed in formalin. Protocolized histological sections (5μm) were obtained throughout each lesion and prepared with Masson's Trichrome and Hematoxylin and Eosin staining. Measurements were performed on a total of 359 slides from the nine lesions. In addition, fresh LA from 18 unused human donor hearts that did not meet criteria for cardiac transplantation were measured at the site where the HIFU device is normally applied. Results Calf LA thickness ranged between 2.5 and 20.1 mm, with a mean of 9.10 mm. HIFU ablation consistently produced a 100% transmural lesion in LA thickness up to 6mm. In addition, a transmural lesion was observed in 91% of tissues that were up to 10 mm thick and in 85% up to 15 mm of thickness. Human LA thickness ranged between 1.2 to 6 mm, with a mean of 3.7 mm. Conclusions Calf LA thickness in this study was greater than human LA thickness. Human LA thickness is generally less than 6mm, and in this range HIFU ablation achieved 100% transmurality. These histological results may correlate with a high success rate of atrial fibrillation ablation using the HIFU system. PMID:20934725

  7. Salvage high-intensity focused ultrasound for the recurrent prostate cancer after radiotherapy in Japan

    Science.gov (United States)

    Shoji, S.; Nakano, M.; Nagata, Y.; Uchida, T.

    2012-10-01

    Aim: to investigate the use of minimally invasive high-intensity focused ultrasound (HIFU) as a salvage therapy in men with localized prostate cancer recurrence following external beam radiotherapy (EBRT), brachytherapy or proton therapy. A review of 22 cases treated using the Sonablate® 500 HIFU device, between August 28, 2002 and April 1, 2010, was carried out. All men had presumed organ-confined, histologically confirmed recurrent prostate adenocarcinoma following radiation therapy. The mean (range) age was 65 (52-80) years with a mean PSA level before radiation therapy of 14.3 (5.7-118) ng/mL. The mean (range) period after radiation therapy to HIFU was 36 (4-96) months. All men with presumed, organ-confined, recurrent disease following EBRT in 14 patients, brachytherapy in 5 patients (4 patients with high-dose brachytherapy with In192 and 1 with low-dose brachytherapy with Au98) or proton therapy in 3 patients treated with salvage HIFU were included. The patients were followed for a mean (range) of 24 months. Biochemical disease-free survival (bDFS) rates in patients with low-, intermediate-and high risk groups were 100%, 86%, and 14%, respectively. All nine patients who received a post HIFU prostate biopsy showed no malignancy. Side-effects included urethral stricture in 4 of the 25 patients (16%) and urinary incontinence in 4 of the 25 patients (16%). Recto-urethral fistula occurred in one patient (4%). Salvage HIFU is a minimally invasive for patients with low-and intermediate risk group with comparable morbidity to other forms of salvage treatment.

  8. Effects of oxytocin on high intensity focused ultrasound (HIFU) ablation of adenomysis: A prospective study

    International Nuclear Information System (INIS)

    Objective: To investigate the effects of oxytocin on high-intensity focused ultrasound (HIFU) ablation for the treatment of adenomyosis. Materials and methods: Eighty-six patients with adenomyosis from three hospitals were randomly assigned to the oxytocin group or control group for HIFU treatment. During HIFU treatment, 80 units of oxytocin was added in 500 ml of 0.9% normal saline running at the rate of 2 ml/min (0.32 U/min) in the oxytocin group, while 0.9% normal saline was used in the control group. Both patients and HIFU operators were blinded to oxytocin or saline application. Treatment results, adverse effects were compared. Results: When using oxytocin, the non-perfused volume (NPV) ratio was 80.7 ± 11.6%, the energy-efficiency factor (EEF) was 8.1 ± 9.9 J/mm3, and the sonication time required to ablate 1 cm3 was 30.0 ± 36.0 s/cm3. When not using oxytocin, the non-perfused volume ratio was 70.8 ± 16.7%, the EEF was 15.8 ± 19.6 J/mm3, and the sonication time required to ablate 1 cm3 was 58.2 ± 72.7 S/cm3. Significant difference in the NPV ratio, EEF, and the sonication time required to ablate 1 cm3 between the two groups was observed. No oxytocin related adverse effects occurred. Conclusion: Oxytocin could significantly decrease the energy for ablating adenomyosis with HIFU, safely enhance the treatment efficiency

  9. Magnetic Resonance-Guided High-Intensity Focused Ultrasound (MR-HIFU) in Treatment of Symptomatic Uterine Myomas

    International Nuclear Information System (INIS)

    Magnetic Resonance-guided High-Intensity Focused Ultrasound (MR-HIFU) is a noninvasive technique for ablation therapy for uterine myomas, where focused ultrasound energy beam generates localized high temperature in the selected area and coagulates chosen tissue, leaving the skin and tissues in between unharmed. Magnetic resonance imaging enables accurate targeting for HIFU as well as temperature monitoring during treatment. MR guidance with 3D anatomical imaging provides reference data for treatment planning, while real-time temperature monitoring aids in controlling ablation process. This review provides basic information regarding methodology, clinical indications for this kind of treatment, expected outcome and patient management during MR-HIFU procedure. The aim of this work is to introduce a new, noninvasive treatment method for uterine leiomyomas and to present a comparison with other currently used methods

  10. Magnetic resonance monitoring of focused ultrasound/magnetic nanoparticle targeting delivery of therapeutic agents to the brain

    OpenAIRE

    Liu, Hao-Li; Hua, Mu-Yi; Yang, Hung-Wei; Huang, Chiung-Yin; Chu, Po-Chun; Wu, Jia-Shin; Tseng, I-Chou; Wang, Jiun-Jie; Yen, Tzu-Chen; Chen, Pin-Yuan; Wei, Kuo-Chen

    2010-01-01

    The superparamagnetic properties of magnetic nanoparticles (MNPs) allow them to be guided by an externally positioned magnet and also provide contrast for MRI. However, their therapeutic use in treating CNS pathologies in vivo is limited by insufficient local accumulation and retention resulting from their inability to traverse biological barriers. The combined use of focused ultrasound and magnetic targeting synergistically delivers therapeutic MNPs across the blood–brain barrier to enter th...

  11. Efficiency of drug delivery enhanced by acoustic pressure during blood–brain barrier disruption induced by focused ultrasound

    OpenAIRE

    Yang, Feng-Yi

    2012-01-01

    Feng-Yi Yang, Pei-Yi LeeDepartment of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, TaiwanPurpose: We evaluated the delivery efficiency of intravenously injected large molecular agents, before and after disruption of the blood–brain barrier (BBB-D), induced by focused ultrasound (FUS) using various acoustic parameters.Materials and methods: Male Sprague-Dawley rats were injected intravenously with Evans blue (EB) before or after BBB-D induction...

  12. Impact of standing wave effects on transcranial focused ultrasound disruption of the blood-brain barrier in a rat model

    OpenAIRE

    O’Reilly, Meaghan A.; Huang, Yuexi; Hynynen, Kullervo

    2010-01-01

    Microbubble mediated disruption of the blood brain barrier (BBB) for targeted drug delivery using focused ultrasound shows great potential as a therapy for a wide range of brain disorders. This technique is currently at the pre-clinical stage and important work is being conducted in animal models. Measurements of standing waves in ex vivo rat skulls were conducted using an optical hydrophone and a geometry dependence was identified. Standing waves could not be eliminated through the use of sw...

  13. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis

    OpenAIRE

    Fouad Aoun; Ksenija Limani; Alexandre Peltier; Quentin Marcelis; Marc Zanaty; Alexandre Chamoun; Marc Vanden Bossche; Thierry Roumeguère; Roland van Velthoven

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ 2 test. Kaplan-Meier curves, log-rank tests, and Cox regression mod...

  14. Single High Intensity Focused Ultrasound Session as a Whole Gland Primary Treatment for Clinically Localized Prostate Cancer: 10-Year Outcomes

    OpenAIRE

    Ksenija Limani; Fouad Aoun; Serge Holz; Marianne Paesmans; Alexandre Peltier; Roland van Velthoven

    2014-01-01

    Objectives. To assess the treatment outcomes of a single session of whole gland high intensity focused ultrasound (HIFU) for patients with localized prostate cancer (PCa). Methods. Response rates were defined using the Stuttgart and Phoenix criteria. Complications were graded according to the Clavien score. Results. At a median follow-up of 94months, 48 (44.4%) and 50 (46.3%) patients experienced biochemical recurrence for Phoenix and Stuttgart definition, respectively. The 5- and 10-year act...

  15. Preliminary safety and efficacy results with robotic high-intensity focused ultrasound : A single center Indian experience

    OpenAIRE

    Mishra, Shashikant; Sharma, Rajan; Garg, Chandra Prakash; Muthu, V.; Ganpule, Arvind; Sabnis, Ravindra B.; Desai, Mahesh R

    2011-01-01

    Background: There are no Indian data of high-intensity focused ultrasound (HIFU). Being an alternative, still experimental modality, reporting short-term safety outcome is paramount. Aims: This study was aimed at to assess the safety and short-term outcome in patients with prostate cancer treated by HIFU. Settings and Design: A retrospective study of case records of 30 patients undergoing HIFU between January 2008 to September 2010 was designed and conducted. Materials and Methods: The proced...

  16. High-Intensity Focused Ultrasound for the Treatment of Wrinkles and Skin Laxity in Seven Different Facial Areas

    OpenAIRE

    Park, Hyunchul; Kim, Eunjin; Kim, Jeongeun; Ro, Youngsuck; Ko, Jooyeon

    2015-01-01

    Background High-intensity focused ultrasound (HIFU) treatment has recently emerged in response to the increasing demand for noninvasive procedures for skin lifting and tightening. Objective This study was aimed at evaluating the clinical efficacy of and patient satisfaction with HIFU treatment for wrinkles and laxity in seven different areas of the face in Asian skin. Methods Twenty Korean patients with facial wrinkle and laxity were analyzed after a single session of HIFU treatment. Two inde...

  17. Light Focusing and Two-Dimensional Imaging Through Scattering Media using the Photoacoustic Transmission-Matrix with an Ultrasound Array

    CERN Document Server

    Chaigne, Thomas; Katz, Ori; Bossy, Emmanuel; Gigan, Sylvain

    2014-01-01

    We implement the photoacoustic transmission-matrix approach on a two-dimensional photoacoustic imaging system, using a 15 MHz linear ultrasound array. Using a black leaf skeleton as a complex absorbing structure, we demonstrate that the photoacoustic transmission-matrix approach allows to reveal structural features that are invisible in conventional photoacoustic images, as well as to selectively control light focusing on absorbing targets, leading to a local enhancement of the photoacoustic signal.

  18. H-mode accelerating structures with permanent-magnet quadrupole beam focusing

    Science.gov (United States)

    Kurennoy, S. S.; Rybarcyk, L. J.; O'Hara, J. F.; Olivas, E. R.; Wangler, T. P.

    2012-09-01

    We have developed high-efficiency normal-conducting rf accelerating structures by combining H-mode resonator cavities and a transverse beam focusing by permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of interdigital H-mode (IH-PMQ) structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. Results of the combined 3D modeling—electromagnetic computations, multiparticle beam-dynamics simulations with high currents, and thermal-stress analysis—for an IH-PMQ accelerator tank are presented. The accelerating-field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of electromagnetic and beam-dynamics modeling. Measurements of a cold model of the IH-PMQ tank show a good agreement with the calculations. Examples of cross-bar H-mode structures with PMQ focusing for higher beam velocities are also presented. H-PMQ accelerating structures following a short radio-frequency quadrupole accelerator can be used both in the front end of ion linacs or in stand-alone applications.

  19. Noninvasive, localized, and transient brain drug delivery using focused ultrasound and microbubbles

    Science.gov (United States)

    Choi, James J.

    In the United States, Alzheimer's disease (AD), Parkinson's disease (PD), and brain cancer caused 72,432, 19,566 and 12,886 deaths in 2006, respectively. Whereas the number of deaths due to major disorders such as heart disease, stroke, and prostate cancer have decreased since 2006, deaths attributed to AD, PD, and brain cancer have not. Treatment options for patients with CNS disorders remain limited despite significant advances in knowledge of CNS disease pathways and development of neurologically potent agents. One of the major obstacles is that the cerebral microvasculature is lined by a specialized and highly regulated blood-brain barrier (BBB) that prevents large agents from entering the brain extracellular space. The purpose of this dissertation is to design a noninvasive, localized, and transient BBB opening system using focused ultrasound (FUS) and determine ultrasound and microbubble conditions that can effectively and safely deliver large pharmacologically-relevant-sized agents to the brain. To meet this end, an in vivo mouse brain drug delivery system using a stereotactic-based targeting method was developed. FUS was applied noninvasively through the intact skin and skull, which allowed for long-term and high-throughput studies. With this system, more than 150 mice were exposed to one of 31 distinct acoustic and microbubble conditions. The feasibility of delivering a large MRI contrast agent was first demonstrated in vivo in both wild-type and transgenic Alzheimer's disease model (APP/PS1) mice. A wide range of acoustic and microbubble conditions were then evaluated for their ability to deliver agents to a target region. Interestingly, the possible design space of parameters was found to be vast and different conditions resulted in distinct spatial distributions and doses delivered. In particular, BBB opening was shown to be dependent on the microbubble diameter, acoustic pressure, pulse repetition frequency (PRF), and pulse length (PL). Each set of

  20. The role of acoustic nonlinearity in tissue heating behind the rib cage using high intensity focused ultrasound phased array

    OpenAIRE

    Yuldashev, Petr V.; Shmeleva, Svetlana M.; Ilyin, Sergey A.; Sapozhnikov, Oleg A.; Gavrilov, Leonid R.; Khokhlova, Vera A.

    2013-01-01

    The goal of this study was to investigate theoretically the effects of nonlinear propagation in a high intensity focused ultrasound (HIFU) field produced by a therapeutic phased array and the resultant heating of tissue behind a rib cage. Three configurations of focusing were simulated: in water, in water with ribs in the beam path, and in water with ribs backed by a layer of soft tissue. The Westervelt equation was used to model the nonlinear HIFU field and a 1 MHz phased array consisting of...

  1. Growth inhibition of high-intensity focused ultrasound on hepatic cancer in vivo

    Institute of Scientific and Technical Information of China (English)

    Xiu-Jie Wang; Shu-Lan Yuan; Yan-Rong Lu; Jie Zhang; Bo-Tao Liu; Wen-Fu Zeng; Yue-Ming He; Yu-Rui Fu

    2005-01-01

    AIM: To investigate the damaging effect of high-intensity focused ultrasound (HIFU) on cancer cells and the inhibitory effect on tumor growth.METHODS: Murine H22 hepatic cancer cells were treated with HIFU at the same intensity for different lengths of time and at different intensities for the same length of timein vitro, the dead cancer cells were determined by trypan blue staining. Two groups of cancer cells treated with HIFU at the lowest and highest intensity were inoculated into mice. Tumor masses were removed and weighed after 2 wk, tumor growth in each group was confirmed pathologically.RESULTS: The death rate of cancer cells treated with HIFU at 1 000 W/cm2 for 0.5, 1, 2, 4, 8, and 12 s was 3.11±1.21%, 13.37±2.56%, 38.84±3.68%, 47.22±5.76%,87.55±7.32%, and 94.33±8.11%, respectively. A positive relationship between the death rates of cancer ceils and the length of HIFU treatment time was found (r = 0.96,P<0.01). The death rate of cancer cells treated with HIFU at the intensity of 100, 200, 400, 600, 800, and 1 000 W/cm2 for 8 s was 26.31±3.26%, 31.00±3.87%, 41.97±5.86%,72.23±8.12%, 94.90±8.67%, and 99.30±9.18%,respectively. A positive relationship between the death rates of cancer cells and the intensities of HIFU treatment was confirmed (r = 0.98, P<0.01). The cancer cells treated with HIFU at 1 000 W/cm2 for 8 s were inoculated into mice ex vivo. The tumor inhibitory rate was 90.35%compared to the control (P<0.01). In the experimental group inoculated with the cancer cells treated with HIFU at 1 000 W/cm2 for 0.5 s, the tumor inhibitory rate was 22.9% (P<0.01). By pathological examination, tumor growth was confirmed in 8 out of 14 mice (57.14%, 8/14)inoculated with the cancer cells treated with HIFU at 1 000 W/cm2 for 8 s, which was significantly lower than that in the control (100%, 15/15, P<0.05).CONCLUSION: HIFU is effective on killing or damage of H22 hepatic cancer cellsin vitro and on inhibiting tumor growth in mice ex vivo.

  2. Therapeutic Effects of Microbubbles Added to Combined High-Intensity Focused Ultrasound and Chemotherapy in a Pancreatic Cancer Xenograft Model

    Science.gov (United States)

    Yu, Mi Hye; Kim, Hae Ri; Kim, Bo Ram; Park, Eun-Joo; Kim, Hoe Suk; Han, Joon Koo; Choi, Byung Ihn

    2016-01-01

    Objective To investigate whether high-intensity focused ultrasound (HIFU) combined with microbubbles enhances the therapeutic effects of chemotherapy. Materials and Methods A pancreatic cancer xenograft model was established using BALB/c nude mice and luciferase-expressing human pancreatic cancer cells. Mice were randomly assigned to five groups according to treatment: control (n = 10), gemcitabine alone (GEM; n = 12), HIFU with microbubbles (HIFU + MB, n = 11), combined HIFU and gemcitabine (HIGEM; n = 12), and HIGEM + MB (n = 13). After three weekly treatments, apoptosis rates were evaluated using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay in two mice per group. Tumor volume and bioluminescence were monitored using high-resolution 3D ultrasound imaging and in vivo bioluminescence imaging for eight weeks in the remaining mice. Results The HIGEM + MB group showed significantly higher apoptosis rates than the other groups (p < 0.05) and exhibited the slowest tumor growth. From week 5, the tumor-volume-ratio relative to the baseline tumor volume was significantly lower in the HIGEM + MB group than in the control, GEM, and HIFU + MB groups (p < 0.05). Despite visible distinction, the HIGEM and HIGEM + MB groups showed no significant differences. Conclusion High-intensity focused ultrasound combined with microbubbles enhances the therapeutic effects of gemcitabine chemotherapy in a pancreatic cancer xenograft model. PMID:27587968

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

    International Nuclear Information System (INIS)

    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

  4. 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

    2014-01-01

    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 seconds 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 percent 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

  5. Reflection-mode photoacoustic microscopy using a hollow focused ultrasound transducer for in vivo imaging of blood vessels

    Institute of Scientific and Technical Information of China (English)

    Yuan Yi; Yang Si-Hua

    2012-01-01

    A reflection-mode photoacoustic microscope using a hollow focused ultrasound transducer is developed for highresolution in vivo imaging.A confocal structure of the laser and the ultrasound is used to improve the system resolution.The axial and lateral resolutions of the system are measured to be~32 μm and~58 μm,respectively.Ex vivo and in vivo modes are tested to validate the imaging capability of the photoacoustic microscope.The adjacent vein and artery can be seen clearly from the reconstructed photoacoustic images.The results demonstrate that the reflectionmode photoacoustic microscope can be used for high-resolution imaging of micro-blood vessels,which would be of great benefit for monitoring the neovascularization in tumor angiogenesis.

  6. Focused ultrasound treatment of abscesses induced by methicillin resistant Staphylococcus aureus: Feasibility study in a mouse model

    International Nuclear Information System (INIS)

    Purpose: To study the therapeutic effect of focused ultrasound on abscesses induced by methicillin-resistantStaphylococcus aureus (MRSA). MRSA is a major nosocomial pathogen where immunocompromised patients are prone to develop infections that are less and less responsive to regular treatments. Because of its capability to induce a rise of temperature at a very precise location, the use of focused ultrasound represents a considerable opportunity for therapy of localized MRSA-related infections. Methods: 50μl of MRSA strain USA400 bacteria suspension at a concentration of 1.32 ± 0.5 × 105 colony forming units (cfu)/μl was injected subcutaneously in the left flank of BALB/c mice. An abscess of 6 ± 2 mm in diameter formed after 48 h. A transducer operating at 3 MHz with a focal length of 50 mm and diameter of 32 mm was used to treat the abscess. The focal point was positioned 2 mm under the skin at the abscess center. Forty-eight hours after injection four ultrasound exposures of 9 s each were applied to each abscess under magnetic resonance imaging guidance. Each exposure was followed by a 1 min pause. These parameters were based on preliminary experiments to ensure repetitive accurate heating of the abscess. Real-time estimation of change of temperature was done using water-proton resonance frequency and a communication toolbox (matMRI) developed inhouse. Three experimental groups of animals each were tested: control, moderate temperature (MT), and high temperature (HT). MT and HT groups reached, respectively, 52.3 ± 5.1 and 63.8 ± 7.5 °C at the end of exposure. Effectiveness of the treatment was assessed by evaluating the bacteria amount of the treated abscess 1 and 4 days after treatment. Myeloperoxidase (MPO) assay evaluating the neutrophil amount was performed to assess the local neutrophil recruitment and the white blood cell count was used to evaluate the systemic inflammatory response after focused ultrasound treatment. Results: Macroscopic

  7. A Focused Low-Intensity Pulsed Ultrasound (FLIPUS) System for Cell Stimulation: Physical and Biological Proof of Principle.

    Science.gov (United States)

    Puts, Regina; Ruschke, Karen; Ambrosi, Thomas H; Kadow-Romacker, Anke; Knaus, Petra; Jenderka, Klaus-Vitold; Raum, Kay

    2016-01-01

    Quantitative ultrasound (QUS) is a promising technique for bone tissue evaluation. Highly focused transducers used for QUS also have the capability to be applied for tissue-regenerative purposes and can provide spatially limited deposition of acoustic energy. We describe a focused low-intensity pulsed ultrasound (FLIPUS) system, which has been developed for the stimulation of cell monolayers in the defocused far field of the transducer through the bottom of the well plate. Tissue culture well plates, carrying the cells, were incubated in a special chamber, immersed in a temperature-controlled water tank. A stimulation frequency of 3.6 MHz provided an optimal sound transmission through the polystyrene well plate. The ultrasound was pulsed for 20 min daily at 100-Hz repetition frequency with 27.8% duty cycle. The calibrated output intensity corresponded to I(SATA) = 44.5 ± 7.1 mW/cm2, which is comparable to the most frequently reported nominal output levels in LIPUS studies. No temperature change by the ultrasound exposure was observed in the well plate. The system was used to stimulate rat mesenchymal stem cells (rMSCs). The applied intensity had no apoptotic effect and enhanced the expression of osteogenic markers, i.e., osteopontin (OPN), collagen 1 (Col-1), the osteoblast-specific transcription factor-Runx-2 and E11 protein, an early osteocyte marker, in stimulated cells on day 5. The proposed FLIPUS setup opens new perspectives for the evaluation of the mechanistic effects of LIPUS. PMID:26552085

  8. Performance of solenoids vs. quadrupoles in focusing and energy selection of laser accelerated protons

    OpenAIRE

    Hofmann, Ingo

    2013-01-01

    Using laser accelerated protons or ions for various applications - for example in particle therapie or short-pulse radiographic diagnostics - requires an effective method of focusing and energy selection. We derive an analytical scaling for the performance of a solenoid compared with a doublet/triplet as function of the energy, which is confirmed by TRACEWIN simulations. The scaling shows that above a few MeV a solenoid needs to be pulsed or super-conducting, whereas the quadrupoles can remai...

  9. The research of intensity focused ultrasound on the treatment of allergic rhinitis%聚焦超声治疗变应性鼻炎研究进展

    Institute of Scientific and Technical Information of China (English)

    林欣然; 张龙城

    2012-01-01

    Allergic rhinitis is a common disease in otorhinolaryngology, there are lots of physiotherapies now, the overview of the research of intensily focused ultrasound on the treatment of allergic rhinitis was mainly reviewed.

  10. Ultrasound-Guided Transesophageal High-Intensity Focused Ultrasound Cardiac Ablation in a Beating Heart: A Pilot Feasibility Study in Pigs.

    Science.gov (United States)

    Bessiere, Francis; N'djin, W Apoutou; Colas, Elodie Constanciel; Chavrier, Françoise; Greillier, Paul; Chapelon, Jean Yves; Chevalier, Philippe; Lafon, Cyril

    2016-08-01

    Catheter ablation for the treatment of arrhythmia is associated with significant complications and often-repeated procedures. Consequently, a less invasive and more efficient technique is required. Because high-intensity focused ultrasound (HIFU) enables the generation of precise thermal ablations in deep-seated tissues without harming the tissues in the propagation path, it has the potential to be used as a new ablation technique. A system capable of delivering HIFU into the heart by a transesophageal route using ultrasound (US) imaging guidance was developed and tested in vivo in six male pigs. HIFU exposures were performed on atria and ventricles. At the time of autopsy, visual inspection identified thermal lesions in the targeted areas in three of the animals. These lesions were confirmed by histologic analysis (mean size: 5.5 mm(2) × 11 mm(2)). No esophageal thermal injury was observed. One animal presented with bradycardia due to an atrio-ventricular block, which provides real-time confirmation of an interaction between HIFU and the electrical circuits of the heart. Thus, US-guided HIFU has the potential to minimally invasively create myocardial lesions without an intra-cardiac device. PMID:27158083

  11. Determining temperature distribution in tissue in the focal plane of the high (>100 W/cm(2)) intensity focused ultrasound beam using phase shift of ultrasound echoes.

    Science.gov (United States)

    Karwat, Piotr; Kujawska, Tamara; Lewin, Peter A; Secomski, Wojciech; Gambin, Barbara; Litniewski, Jerzy

    2016-02-01

    In therapeutic applications of High Intensity Focused Ultrasound (HIFU) the guidance of the HIFU beam and especially its focal plane is of crucial importance. This guidance is needed to appropriately target the focal plane and hence the whole focal volume inside the tumor tissue prior to thermo-ablative treatment and beginning of tissue necrosis. This is currently done using Magnetic Resonance Imaging that is relatively expensive. In this study an ultrasound method, which calculates the variations of speed of sound in the locally heated tissue volume by analyzing the phase shifts of echo-signals received by an ultrasound scanner from this very volume is presented. To improve spatial resolution of B-mode imaging and minimize the uncertainty of temperature estimation the acoustic signals were transmitted and received by 8 MHz linear phased array employing Synthetic Transmit Aperture (STA) technique. Initially, the validity of the algorithm developed was verified experimentally in a tissue-mimicking phantom heated from 20.6 to 48.6 °C. Subsequently, the method was tested using a pork loin sample heated locally by a 2 MHz pulsed HIFU beam with focal intensity ISATA of 129 W/cm(2). The temperature calibration of 2D maps of changes in the sound velocity induced by heating was performed by comparison of the algorithm-determined changes in the sound velocity with the temperatures measured by thermocouples located in the heated tissue volume. The method developed enabled ultrasound temperature imaging of the heated tissue volume from the very inception of heating with the contrast-to-noise ratio of 3.5-12 dB in the temperature range 21-56 °C. Concurrently performed, conventional B-mode imaging revealed CNR close to zero dB until the temperature reached 50 °C causing necrosis. The data presented suggest that the proposed method could offer an alternative to MRI-guided temperature imaging for prediction of the location and extent of the thermal lesion prior to applying the

  12. Determining temperature distribution in tissue in the focal plane of the high (>100 W/cm(2)) intensity focused ultrasound beam using phase shift of ultrasound echoes.

    Science.gov (United States)

    Karwat, Piotr; Kujawska, Tamara; Lewin, Peter A; Secomski, Wojciech; Gambin, Barbara; Litniewski, Jerzy

    2016-02-01

    In therapeutic applications of High Intensity Focused Ultrasound (HIFU) the guidance of the HIFU beam and especially its focal plane is of crucial importance. This guidance is needed to appropriately target the focal plane and hence the whole focal volume inside the tumor tissue prior to thermo-ablative treatment and beginning of tissue necrosis. This is currently done using Magnetic Resonance Imaging that is relatively expensive. In this study an ultrasound method, which calculates the variations of speed of sound in the locally heated tissue volume by analyzing the phase shifts of echo-signals received by an ultrasound scanner from this very volume is presented. To improve spatial resolution of B-mode imaging and minimize the uncertainty of temperature estimation the acoustic signals were transmitted and received by 8 MHz linear phased array employing Synthetic Transmit Aperture (STA) technique. Initially, the validity of the algorithm developed was verified experimentally in a tissue-mimicking phantom heated from 20.6 to 48.6 °C. Subsequently, the method was tested using a pork loin sample heated locally by a 2 MHz pulsed HIFU beam with focal intensity ISATA of 129 W/cm(2). The temperature calibration of 2D maps of changes in the sound velocity induced by heating was performed by comparison of the algorithm-determined changes in the sound velocity with the temperatures measured by thermocouples located in the heated tissue volume. The method developed enabled ultrasound temperature imaging of the heated tissue volume from the very inception of heating with the contrast-to-noise ratio of 3.5-12 dB in the temperature range 21-56 °C. Concurrently performed, conventional B-mode imaging revealed CNR close to zero dB until the temperature reached 50 °C causing necrosis. The data presented suggest that the proposed method could offer an alternative to MRI-guided temperature imaging for prediction of the location and extent of the thermal lesion prior to applying the

  13. Potential of minimally invasive procedures in the treatment of uterine fibroids: a focus on magnetic resonance-guided focused ultrasound therapy

    Directory of Open Access Journals (Sweden)

    Fischer K

    2015-11-01

    Full Text Available Krisztina Fischer,1–3 Nathan J McDannold,1 Clare M Tempany,1 Ferenc A Jolesz,1,† Fiona M Fennessy1,4 1Department of Radiology, 2Renal Division, 3Biomedical Engineering Division, Brigham and Women’s Hospital, 4Department of Radiology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA †Ferenc A Jolesz passed away on December 31, 2014 Abstract: Minimally invasive treatment options are an important part of the uterine fibroid-treatment arsenal, especially among younger patients and in those who plan future pregnancies. This article provides an overview of the currently available minimally invasive therapy options, with a special emphasis on a completely noninvasive option: magnetic resonance-guided focused ultrasound (MRgFUS. In this review, we describe the background of MRgFUS, the patient-selection criteria for MRgFUS, and how the procedure is performed. We summarize the published clinical trial results, and review the literature on pregnancy post-MRgFUS and on the cost-effectiveness of MRgFUS. Keywords: uterine fibroids, MRgFUS, focused ultrasound, minimally invasive treatment 

  14. Long-term Efficacy of Micro-focused Ultrasound with Visualization for Lifting and Tightening Lax Facial and Neck Skin Using a Customized Vectoring Treatment Method

    OpenAIRE

    Werschler, William Philip; Werschler, Pam Schell

    2016-01-01

    Background: Micro-focused ultrasound with visualization has been cleared by the United States Food and Drug Administration to noninvasively lift the eyebrow, lift submental and neck tissue, and improve lines and wrinkles of the décolleté. Objective: The objective of this prospective, open-label pilot study was to evaluate the efficacy and safety of patient-specific, customized micro-focused ultrasound with visualization treatment with vertical vectoring to lift and tighten facial and neck tis...

  15. Evaluation of local density enhancement of microcapsules in artificial blood vessel during exposure to focused ultrasound

    International Nuclear Information System (INIS)

    We have proposed a physical DDS (Drug Delivery System) which makes use of microcapsules of μm size, which may contain a specified drug and also are easily affected by ultrasound exposure near their resonant frequency, to release various kinds of medications. These capsules are easily detected and actuated by ultrasound. However, because of the diffusion of capsules after injection into human body, it was difficult to enhance the efficiency of drug delivery. Thus we have considered a method for controlling the density of capsules in flow which uses acoustic radiation force, which moves the capsules to balance flow resistance. We have experimented with trapping microcapsules or microbubbles in flow of an artificial blood vessel. We have evaluated the effect of radiation force by measuring the trapped area of capsules or bubbles for various frequencies, sound pressures, and exposure times of sinusoidal ultrasound. The trapped area of capsules or bubbles increased with sound pressure and exposure time, and decreased with frequency. From those results, we have derived optimal conditions for trapping the capsules or bubbles.

  16. Evaluation of local density enhancement of microcapsules in artificial blood vessel during exposure to focused ultrasound

    Science.gov (United States)

    Nakamoto, Ryusuke; Masuda, Kohji; Watarai, Nobuyuki; Taguchi, Yuto; Kato, Toshikazu; Yoshinaga, Takashi; Miyamoto, Yoshitaka; Chiba, Toshio

    2011-09-01

    We have proposed a physical DDS (Drug Delivery System) which makes use of microcapsules of μm size, which may contain a specified drug and also are easily affected by ultrasound exposure near their resonant frequency, to release various kinds of medications. These capsules are easily detected and actuated by ultrasound. However, because of the diffusion of capsules after injection into human body, it was difficult to enhance the efficiency of drug delivery. Thus we have considered a method for controlling the density of capsules in flow which uses acoustic radiation force, which moves the capsules to balance flow resistance. We have experimented with trapping microcapsules or microbubbles in flow of an artificial blood vessel. We have evaluated the effect of radiation force by measuring the trapped area of capsules or bubbles for various frequencies, sound pressures, and exposure times of sinusoidal ultrasound. The trapped area of capsules or bubbles increased with sound pressure and exposure time, and decreased with frequency. From those results, we have derived optimal conditions for trapping the capsules or bubbles.

  17. Combination of bubble liposomes and high-intensity focused ultrasound (HIFU) enhanced antitumor effect by tumor ablation.

    Science.gov (United States)

    Hamano, Nobuhito; Negishi, Yoichi; Takatori, Kyohei; Endo-Takahashi, Yoko; Suzuki, Ryo; Maruyama, Kazuo; Niidome, Takuro; Aramaki, Yukihiko

    2014-01-01

    Ultrasound (US) is used in the clinical setting not only for diagnosis but also for therapy. As a therapeutic US technique, high-intensity focused ultrasound (HIFU) can be applied to treat cancer in a clinical setting. Microbubbles increased temperature and improved the low therapeutic efficiency under HIFU; however, microbubbles have room for improvement in size, stability, and targeting ability. To solve these issues, we reported that "Bubble liposomes" (BLs) containing the US imaging gas (perfluoropropane gas) liposomes were suitable for ultrasound imaging and gene delivery. In this study, we examined whether BLs and HIFU could enhance the ablation area of the tumor and the antitumor effect. First, we histologically analyzed the tumor after BLs and HIFU. The ablation area of the treatment of BLs and HIFU was broader than that of HIFU alone. Next, we monitored the temperature of the tumor, and examined the antitumor effect. The temperature increase with BLs and HIFU treatment was faster and higher than that with HIFU alone. Moreover, treatment with BLs and HIFU enhanced the antitumor effect, which was better than with HIFU alone. Thus, the combination of BLs and HIFU could be efficacious for cancer therapy.

  18. A Bayesian approach for energy-based estimation of acoustic aberrations in high intensity focused ultrasound treatment

    CERN Document Server

    Hosseini, Bamdad; Pichardo, Samuel; Constanciel, Elodie; Drake, James M; Stockie, John M

    2016-01-01

    High intensity focused ultrasound is a non-invasive method for treatment of diseased tissue that uses a beam of ultrasound in order to generate heat within a small volume. A common challenge in application of this technique is that heterogeneity of the biological medium can defocus the ultrasound beam. In this study, the problem of refocusing the beam is reduced to the Bayesian inverse problem of estimating the acoustic aberration due to the biological tissue from acoustic radiative force imaging data. The solution to this problem is a posterior probability density on the aberration which is sampled using a Metropolis-within-Gibbs algorithm. The framework is tested using both a synthetic and experimental dataset. This new approach has the ability to obtain a good estimate of the aberrations from a small dataset, as little as 32 sonication tests, which can lead to significant speedup in the treatment process. Furthermore, this framework is very flexible and can work with a wide range of sonication tests and so...

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

    Energy Technology Data Exchange (ETDEWEB)

    Odéen, Henrik, E-mail: h.odeen@gmail.com; Diakite, Mahamadou [Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84108 and Department of Radiology, University of Utah, Salt Lake City, Utah 84108 (United States); Todd, Nick; Minalga, Emilee; Payne, Allison; Parker, Dennis L. [Department of Radiology, University of Utah, Salt Lake City, Utah 84108 (United States)

    2014-09-15

    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

  20. H-mode Accelerating Structures with PMQ Focusing for Low-Beta Beams

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, Sergey S. [Los Alamos National Laboratory; O' Hara, James F. [Los Alamos National Laboratory; Olivas, Eric R. [Los Alamos National Laboratory; Rybarcyk, Lawrence J. [Los Alamos National Laboratory

    2011-01-01

    We report on results of the project developing high-efficiency normal-conducting RF accelerating structures based on inter-digital H-mode (IH) cavities and the transverse beam focusing with permanent-magnet quadrupoles (PMQ), for beam velocities in the range of a few percent of the speed of light. The shunt impedance of IH-PMQ structures is 10-20 times higher than that of a conventional drift-tube linac, while the transverse size is 4-5 times smaller. The H-PMQ accelerating structures following a short RFQ can be used both in the front end of ion linacs or in stand-alone applications. Results of the combined 3-D modeling -- electromagnetic computations, beam-dynamics simulations with high currents, and thermal-stress analysis -- for a full IH-PMQ accelerator tank are presented. The accelerating field profile in the tank is tuned to provide the best propagation of a 50-mA deuteron beam using coupled iterations of EM and beamdynamics modeling. Multi-particle simulations withParmela and CST Particle Studio have been used to confirm the design. Measurement results of a cold model of the IH-PMQ tank are presented.

  1. Real-time monitoring of high-intensity focused ultrasound thermal therapy using the manifold learning method.

    Science.gov (United States)

    Rangraz, Parisa; Behnam, Hamid; Sobhebidari, Pooya; Tavakkoli, Jahan

    2014-12-01

    High-intensity focused ultrasound (HIFU) induces thermal lesions by increasing the tissue temperature in a tight focal region. The main ultrasound imaging techniques currently used to monitor HIFU treatment are standard pulse-echo B-mode ultrasound imaging, ultrasound temperature estimation and elastography-based methods. The present study was carried out on ex vivo animal tissue samples, in which backscattered radiofrequency (RF) signals were acquired in real time at time instances before, during and after HIFU treatment. The manifold learning algorithm, a non-linear dimensionality reduction method, was applied to RF signals whichconstruct B-mode images to detect the HIFU-induced changes among the image frames obtained during HIFU treatment. In this approach, the embedded non-linear information in the region of interest of sequential images is represented in a 2-D manifold with the Isomap algorithm, and each image is depicted as a point on the reconstructed manifold. Four distinct regions are chosen in the manifold corresponding to the four phases of HIFU treatment (before HIFU treatment, during HIFU treatment, immediately after HIFU treatment and 10-min after HIFU treatment). It was found that disorganization of the points is achieved by increasing the acoustic power, and if the thermal lesion has been formed, the regions of points related to pre- and post-HIFU significantly differ. Moreover, the manifold embedding was repeated on 2-D moving windows in RF data envelopes related to pre- and post-HIFU exposure data frames. It was concluded that if mean values of the points related to pre- and post-exposure frames in the reconstructed manifold are estimated, and if the Euclidean distance between these two mean values is calculated and the sliding window is moved and this procedure is repeated for the whole image, a new image based on the Euclidean distance can be formed in which the HIFU thermal lesion is detectable.

  2. Flooded Lung Generates a Suitable Acoustic Pathway for Transthoracic Application of High Intensity Focused Ultrasound in Liver

    Science.gov (United States)

    Lesser, Thomas Günther; Boltze, Carsten; Schubert, Harald; Wolfram, Frank

    2016-01-01

    Background: In recent years, high intensity focused ultrasound (HIFU) has gained increasing clinical interest as a non-invasive method for local therapy of liver malignancies. HIFU treatment of tumours and metastases in the liver dome is limited due to the adjacent ultrasound blocking lung. One-lung flooding (OLF) enables complete sonography of lung and adjoining organs including liver. HIFU liver ablation passing through the flooded lung could enable a direct intercostal beam path and thus improve dose deposition in liver. In this study, we evaluate the feasibility of an ultrasound guided transthoracic, transpulmonary HIFU ablation of liver using OLF. Methods: After right-side lung flooding, ultrasound guided HIFU was applied transthoracic- transpulmonary into liver to create thermal lesions in three pigs. The HIFU beam was targeted five times into liver, two times at the liver surface and three times deeper into the tissue. During autopsy examinations of lung, diaphragm and liver located in the HIFU path were performed. The focal liver lesions and lung tissue out of the beam path were examined histologically. Results: Fifteen thermal liver lesions were generated by transpulmonary HIFU sonication in all targeted regions. The lesions appeared well-demarcated in grey color with a cigar-shaped configuration. The mean length and width of the superficial and deeper lesions were 15.8 mm (range: 13-18 mm) and 5.8 mm (range: 5-7 mm), and 10.9 mm (range: 9-13 mm) and 3.3 mm (range: 2-5 mm), respectively. Histopathological, all liver lesions revealed a homogeneous thermal necrosis lacking vitality. There were no signs of damage of the overlying diaphragm and lung tissue. Conclusions: Flooded lung is a suitable pathway for applying HIFU to the liver, thus enabling a transthoracic, transpulmonary approach. The enlarged acoustic window could enhance the ablation speed for targets in the hepatic dome. PMID:27766022

  3. Harmonic motion imaging for focused ultrasound (HMIFU): a fully integrated technique for sonication and monitoring of thermal ablation in tissues

    International Nuclear Information System (INIS)

    FUS (focused ultrasound), or HIFU (high-intensity-focused ultrasound) therapy, a minimally or non-invasive procedure that uses ultrasound to generate thermal necrosis, has been proven successful in several clinical applications. This paper discusses a method for monitoring thermal treatment at different sonication durations (10 s, 20 s and 30 s) using the amplitude-modulated (AM) harmonic motion imaging for focused ultrasound (HMIFU) technique in bovine liver samples in vitro. The feasibility of HMI for characterizing mechanical tissue properties has previously been demonstrated. Here, a confocal transducer, combining a 4.68 MHz therapy (FUS) and a 7.5 MHz diagnostic (pulse-echo) transducer, was used. The therapy transducer was driven by a low-frequency AM continuous signal at 25 Hz, producing a stable harmonic radiation force oscillating at the modulation frequency. A pulser/receiver was used to drive the pulse-echo transducer at a pulse repetition frequency (PRF) of 5.4 kHz. Radio-frequency (RF) signals were acquired using a standard pulse-echo technique. The temperature near the ablation region was simultaneously monitored. Both RF signals and temperature measurements were obtained before, during and after sonication. The resulting axial tissue displacement was estimated using one-dimensional cross correlation. When temperature at the focal zone was above 48 deg. C during heating, the coagulation necrosis occurred and tissue damage was irreversible. The HMI displacement profiles in relation to the temperature and sonication durations were analyzed. At the beginning of heating, the temperature at the focus increased sharply, while the tissue stiffness decreased resulting in higher HMI displacements. This was confirmed by an increase of 0.8 μm deg. C-1(r = 0.93, p -1, r = -0.92, p -1, prior to and after lesion formation in seven bovine liver samples, respectively. This technique was thus capable of following the protein-denatured lesion formation based on the

  4. The nursing care for patients of hepatocellular carcinoma treated with transcatheter hepatic arterial chemoembolization and high intensive focus ultrasound

    International Nuclear Information System (INIS)

    Objective: To discuss the nursing measures for patients of hepatocellular carcinoma treated with transcatheter hepatic arterial chemoembolization (TACE) and high intensive focus ultrasound(HIFU). Methods: During the period of Aug.2008-Aug. 2009, TACE together with HIFU were performed in 40 patients with hepatocellular carcinoma. The perioperative nursing measures were summarized. Results: During hospitalization no severe complications, such as dangerous infection, intestinal bleeding, etc. occurred in all patients. Conclusion: Correct and proper perioperative nursing care is of significant importance for the prevention of complications and for the therapeutic effectiveness. (authors)

  5. Three-axis MR-conditional robot for high-intensity focused ultrasound for treating prostate diseases transrectally

    OpenAIRE

    Yiallouras, Christos; Ioannides, Kleanthis; Dadakova, Tetiana; Pavlina, Matt; Bock, Michael; Damianou, Christakis

    2015-01-01

    Background A prototype magnetic resonance image (MRI)-conditional robot was developed for navigating a high-intensity focused ultrasound (HIFU) system in order to treat prostate cancer transrectally. Materials and methods The developed robotic device utilizes three PC-controlled axes: a linear axis for motion along the rectum, an angular axis for rotation in the rectum, and a linear axis to lift the robot up and down. Experiments with the system were performed in a 1.5-T MRI system using gel ...

  6. Adjuvant hormone therapy in patients undergoing high-intensity focused ultrasound therapy for locally advanced prostate cancer

    OpenAIRE

    A. I. Neimark; M. A. Tachalov; B. A. Neimark

    2014-01-01

    Objective: to evaluate the efficiency and safety of using the luteinizing hormone releasing hormone leuprorelin with the Atrigel delivery system in doses of 7.5, 22.5, and 45 mg as an adjuvant regimen in high- and moderate-risk cancer patients who have received high-intensity focused ultrasound (HIFU) therapy.Subjects and methods. Moderate- and high-risk locally advanced prostate cancer (PC) patients treated with HIFU (n = 28) and HIFU in combination with hormone therapy during 6 months (n = ...

  7. Feasibility of laser-integrated high intensity focused ultrasound (HIFU) treatment for bladder tumors: in vitro study (Conference Presentation)

    Science.gov (United States)

    Nguyen, Van Phuc; Park, Suhyun; Oh, Junghwan; Kang, Hyun Wook

    2016-02-01

    Previous studies have shown that photothemal therapy combined with high intensity focused ultrasound (HIFU) can provide a promising method to achieve rapid thermal coagulation during surgical procedures. The current study investigated the feasibility of the laser-integrated high intensity focused ultrasound (HIFU) application to treat bladder tumors by enhancing thermal effects and therapeutic depth in vitro. To generate thermal coagulation, a single element HIFU transducer with a central frequency of 2.0 MHz was used to transmit acoustic energy to 15 fresh porcine bladders injected with an artificial tumor (100 µl gelatin and hemoglobin solution) in vitro. Simultaneously, an 80-W 532-nm laser system was also implemented to induce thermal necrosis in the targeted tissue. The intensity of 570 W/cm2 at the focus of HIFU and laser energy of 0.9 W were applied to all the samples for 40 s. The temperature rise increased up to about 1.6 or 3 folds (i.e., ΔT=32±3.8 K for laser-integrated HIFU, ΔT=20±6.5 K for HIFU only, and ΔT=11±5.6 K for laser only). The estimated lesion depth also increased by 1.3 and 2 folds during the dual-thermal treatment, in comparison with the treatment by either HIFU or laser. The results indicated that the laser-integrated HIFU treatment can be an efficient hyperthermic method for tumor coagulation.

  8. HIGH-INTENSITY FOCUSED ULTRASOUND ABLATION OF PATIENTS WITH LOCALLY ADVANCED PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    L. V. Shaplygin

    2014-01-01

    Full Text Available In this study the results of retrospective analysis of treatment of 311 patients in Samara Oncology Center in 2008–2011 with locally advanced prostate cancer are presented. According to the received treatment patients were divided into 3 groups: 103 underwent HIFU, 101 patients had a course of EBRT, 107 patients received only hormone therapy (HT. Overall survival in patients with locally advanced prostate cancer after HIFU therapy was 86.2 %, after EBRT and HT – 66.3% and 18.1 %, respectively. These data indicate a high clinical efficacy of ultrasound ablation. 

  9. HIGH-INTENSITY FOCUSED ULTRASOUND ABLATION OF PATIENTS WITH LOCALLY ADVANCED PROSTATE CANCER

    Directory of Open Access Journals (Sweden)

    L. V. Shaplygin

    2014-07-01

    Full Text Available In this study the results of retrospective analysis of treatment of 311 patients in Samara Oncology Center in 2008–2011 with locally advanced prostate cancer are presented. According to the received treatment patients were divided into 3 groups: 103 underwent HIFU, 101 patients had a course of EBRT, 107 patients received only hormone therapy (HT. Overall survival in patients with locally advanced prostate cancer after HIFU therapy was 86.2 %, after EBRT and HT – 66.3% and 18.1 %, respectively. These data indicate a high clinical efficacy of ultrasound ablation. 

  10. Spatial-temporal three-dimensional ultrasound plane-by-plane active cavitation mapping for high-intensity focused ultrasound in free field and pulsatile flow.

    Science.gov (United States)

    Ding, Ting; Hu, Hong; Bai, Chen; Guo, Shifang; Yang, Miao; Wang, Supin; Wan, Mingxi

    2016-07-01

    Cavitation plays important roles in almost all high-intensity focused ultrasound (HIFU) applications. However, current two-dimensional (2D) cavitation mapping could only provide cavitation activity in one plane. This study proposed a three-dimensional (3D) ultrasound plane-by-plane active cavitation mapping (3D-UPACM) for HIFU in free field and pulsatile flow. The acquisition of channel-domain raw radio-frequency (RF) data in 3D space was performed by sequential plane-by-plane 2D ultrafast active cavitation mapping. Between two adjacent unit locations, there was a waiting time to make cavitation nuclei distribution of the liquid back to the original state. The 3D cavitation map equivalent to the one detected at one time and over the entire volume could be reconstructed by Marching Cube algorithm. Minimum variance (MV) adaptive beamforming was combined with coherence factor (CF) weighting (MVCF) or compressive sensing (CS) method (MVCS) to process the raw RF data for improved beamforming or more rapid data processing. The feasibility of 3D-UPACM was demonstrated in tap-water and a phantom vessel with pulsatile flow. The time interval between temporal evolutions of cavitation bubble cloud could be several microseconds. MVCF beamformer had a signal-to-noise ratio (SNR) at 14.17dB higher, lateral and axial resolution at 2.88times and 1.88times, respectively, which were compared with those of B-mode active cavitation mapping. MVCS beamformer had only 14.94% time penalty of that of MVCF beamformer. This 3D-UPACM technique employs the linear array of a current ultrasound diagnosis system rather than a 2D array transducer to decrease the cost of the instrument. Moreover, although the application is limited by the requirement for a gassy fluid medium or a constant supply of new cavitation nuclei that allows replenishment of nuclei between HIFU exposures, this technique may exhibit a useful tool in 3D cavitation mapping for HIFU with high speed, precision and resolution

  11. Spatial-temporal three-dimensional ultrasound plane-by-plane active cavitation mapping for high-intensity focused ultrasound in free field and pulsatile flow.

    Science.gov (United States)

    Ding, Ting; Hu, Hong; Bai, Chen; Guo, Shifang; Yang, Miao; Wang, Supin; Wan, Mingxi

    2016-07-01

    Cavitation plays important roles in almost all high-intensity focused ultrasound (HIFU) applications. However, current two-dimensional (2D) cavitation mapping could only provide cavitation activity in one plane. This study proposed a three-dimensional (3D) ultrasound plane-by-plane active cavitation mapping (3D-UPACM) for HIFU in free field and pulsatile flow. The acquisition of channel-domain raw radio-frequency (RF) data in 3D space was performed by sequential plane-by-plane 2D ultrafast active cavitation mapping. Between two adjacent unit locations, there was a waiting time to make cavitation nuclei distribution of the liquid back to the original state. The 3D cavitation map equivalent to the one detected at one time and over the entire volume could be reconstructed by Marching Cube algorithm. Minimum variance (MV) adaptive beamforming was combined with coherence factor (CF) weighting (MVCF) or compressive sensing (CS) method (MVCS) to process the raw RF data for improved beamforming or more rapid data processing. The feasibility of 3D-UPACM was demonstrated in tap-water and a phantom vessel with pulsatile flow. The time interval between temporal evolutions of cavitation bubble cloud could be several microseconds. MVCF beamformer had a signal-to-noise ratio (SNR) at 14.17dB higher, lateral and axial resolution at 2.88times and 1.88times, respectively, which were compared with those of B-mode active cavitation mapping. MVCS beamformer had only 14.94% time penalty of that of MVCF beamformer. This 3D-UPACM technique employs the linear array of a current ultrasound diagnosis system rather than a 2D array transducer to decrease the cost of the instrument. Moreover, although the application is limited by the requirement for a gassy fluid medium or a constant supply of new cavitation nuclei that allows replenishment of nuclei between HIFU exposures, this technique may exhibit a useful tool in 3D cavitation mapping for HIFU with high speed, precision and resolution

  12. Electron acceleration by tightly focused radially polarized few-cycle laser pulses

    Institute of Scientific and Technical Information of China (English)

    Liu Jin-Lu; Sheng Zheng-Ming; Zheng Jun

    2012-01-01

    Within the framework of plane-wave angular spectrum analysis of the electromagnetic field structure,a solution valid for tightly focused radially polarized few-cycle laser pulses propagating in vacuum is presented.The resulting field distribution is significantly different from that based on the paraxial approximation for pulses with either small or large beam diameters.We compare the electron accelerations obtained with the two solutions and find that the energy gain obtained with our new solution is usually much larger than that with the paraxial approximation solution.

  13. 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

    2016-01-01

    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. PMID:27535093

  14. 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

    2016-01-01

    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. PMID:27535093

  15. 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

    2016-08-01

    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.

  16. In vivo demonstration of reflection artifact reduction in photoacoustic imaging using synthetic aperture photoacoustic-guided focused ultrasound (PAFUSion).

    Science.gov (United States)

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

    2016-08-01

    Reflection artifacts caused by acoustic inhomogeneities are a critical problem in epi-mode biomedical photoacoustic imaging. High light fluence beneath the probe results in photoacoustic transients, which propagate into the tissue and reflect back from echogenic structures. These reflection artifacts cause problems in image interpretation and significantly impact the contrast and imaging depth. We recently proposed a method called PAFUSion (Photoacoustic-guided focused ultrasound) to identify such reflection artifacts in photoacoustic imaging. In its initial version, PAFUSion mimics the inward-travelling wavefield from small blood vessel-like PA sources by applying ultrasound pulses focused towards these sources, and thus provides a way to identify the resulting reflection artifacts. In this work, we demonstrate reduction of reflection artifacts in phantoms and in vivo measurements on human volunteers. In view of the spatially distributed PA sources that are found in clinical applications, we implemented an improved version of PAFUSion where photoacoustic signals are backpropagated to imitate the inward travelling wavefield and thus the reflection artifacts. The backpropagation is performed in a synthetic way based on the pulse-echo acquisitions after transmission on each single element of the transducer array. The results provide a direct confirmation that reflection artifacts are prominent in clinical epi-photoacoustic imaging, and that PAFUSion can strongly reduce these artifacts to improve deep-tissue photoacoustic imaging. PMID:27570690

  17. Noninvasive focused ultrasound stimulation can modulate phase-amplitude coupling between neuronal oscillations in the rat hippocampus

    Directory of Open Access Journals (Sweden)

    Yi Yuan

    2016-07-01

    Full Text Available Noninvasive focused ultrasound stimulation (FUS can be used to modulate neural activity with high spatial resolution. Phase-amplitude coupling (PAC between neuronal oscillations is tightly associated with cognitive processes, including learning, attention and memory. In this study, we investigated the effect of FUS on PAC between neuronal oscillations and established the relationship between the PAC index and ultrasonic intensity. The rat hippocampus was stimulated using focused ultrasound at different spatial-average pulse-average ultrasonic intensities (3.9 W/cm2, 9.6 W/cm2, and 19.2 W/cm2. The local field potentials (LFPs in the rat hippocampus were recorded before and after FUS. Then, we analyzed PAC between neuronal oscillations using a PAC calculation algorithm. Our results showed that FUS significantly modulated PAC between the theta (4-8 Hz and gamma (30-80 Hz bands and between the alpha (9-13 Hz and ripple (81-200 Hz bands in the rat hippocampus, and PAC increased with incremental increases in ultrasonic intensity.

  18. Noninvasive Focused Ultrasound Stimulation Can Modulate Phase-Amplitude Coupling between Neuronal Oscillations in the Rat Hippocampus

    Science.gov (United States)

    Yuan, Yi; Yan, Jiaqing; Ma, Zhitao; Li, Xiaoli

    2016-01-01

    Noninvasive focused ultrasound stimulation (FUS) can be used to modulate neural activity with high spatial resolution. Phase-amplitude coupling (PAC) between neuronal oscillations is tightly associated with cognitive processes, including learning, attention, and memory. In this study, we investigated the effect of FUS on PAC between neuronal oscillations and established the relationship between the PAC index and ultrasonic intensity. The rat hippocampus was stimulated using focused ultrasound at different spatial-average pulse-average ultrasonic intensities (3.9, 9.6, and 19.2 W/cm2). The local field potentials (LFPs) in the rat hippocampus were recorded before and after FUS. Then, we analyzed PAC between neuronal oscillations using a PAC calculation algorithm. Our results showed that FUS significantly modulated PAC between the theta (4–8 Hz) and gamma (30–80 Hz) bands and between the alpha (9–13 Hz) and ripple (81–200 Hz) bands in the rat hippocampus, and PAC increased with incremental increases in ultrasonic intensity. PMID:27499733

  19. In vivo demonstration of reflection artifact reduction in photoacoustic imaging using synthetic aperture photoacoustic-guided focused ultrasound (PAFUSion).

    Science.gov (United States)

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

    2016-08-01

    Reflection artifacts caused by acoustic inhomogeneities are a critical problem in epi-mode biomedical photoacoustic imaging. High light fluence beneath the probe results in photoacoustic transients, which propagate into the tissue and reflect back from echogenic structures. These reflection artifacts cause problems in image interpretation and significantly impact the contrast and imaging depth. We recently proposed a method called PAFUSion (Photoacoustic-guided focused ultrasound) to identify such reflection artifacts in photoacoustic imaging. In its initial version, PAFUSion mimics the inward-travelling wavefield from small blood vessel-like PA sources by applying ultrasound pulses focused towards these sources, and thus provides a way to identify the resulting reflection artifacts. In this work, we demonstrate reduction of reflection artifacts in phantoms and in vivo measurements on human volunteers. In view of the spatially distributed PA sources that are found in clinical applications, we implemented an improved version of PAFUSion where photoacoustic signals are backpropagated to imitate the inward travelling wavefield and thus the reflection artifacts. The backpropagation is performed in a synthetic way based on the pulse-echo acquisitions after transmission on each single element of the transducer array. The results provide a direct confirmation that reflection artifacts are prominent in clinical epi-photoacoustic imaging, and that PAFUSion can strongly reduce these artifacts to improve deep-tissue photoacoustic imaging.

  20. Collection and focusing of laser accelerated ion beams for therapy applications

    Science.gov (United States)

    Hofmann, Ingo; Meyer-Ter-Vehn, Jürgen; Yan, Xueqing; Orzhekhovskaya, Anna; Yaramyshev, Stepan

    2011-03-01

    Experimental results in laser acceleration of protons and ions and theoretical predictions that the currently achieved energies might be raised by factors 5-10 in the next few years have stimulated research exploring this new technology for oncology as a compact alternative to conventional synchrotron based accelerator technology. The emphasis of this paper is on collection and focusing of the laser produced particles by using simulation data from a specific laser acceleration model. We present a scaling law for the “chromatic emittance” of the collector—here assumed as a solenoid lens—and apply it to the particle energy and angular spectra of the simulation output. For a 10 Hz laser system we find that particle collection by a solenoid magnet well satisfies requirements of intensity and beam quality as needed for depth scanning irradiation. This includes a sufficiently large safety margin for intensity, whereas a scheme without collection—by using mere aperture collimation—hardly reaches the needed intensities.

  1. Use of high-intensity focused ultrasound in the treatment of both benign and malignant prostatic disease

    Science.gov (United States)

    Kernen, Kenneth M.; Miles, Brian J.

    2000-05-01

    Prostate cancer, the most common malignancy in men in the United States, accounts for more than 29% of all male cancers diagnosed and 13% of all cancer deaths. This translates into approximately 200,000 men diagnosed and 37,000 men who will die from the disease this year in this country. A significant number of patients ultimately choose external beam radiation or interstitial radioactive implants (brachytherapy) combined with external beam radiotherapy as their primary treatment. Approximately 25 - 35% of external beam irradiation patients and 20 - 30% of interstitial implants combined with external beam radiotherapy will fail within 10 years. The treatment options for patients with localized radiorecurrent disease include watchful waiting, endocrine therapy, salvage radiotherapy, and salvage radical prostatectomy, cryotherapy and now high intensity focused ultrasound therapy (HIFU). Although some studies regarding watchful waiting demonstrated comparable results to formal treatment for early prostate cancer, other studies have shown metastatic and mortality rates that are significantly higher, and that radiorecurrent patients would have even greater rates of metastasis and progression to death. Prostate cancer cure by means of endocrine therapy is highly unlikely and its role is still one of palliation with a side effect profile which includes hot flashes, osteoporosis, fatigue, loss of muscle mass, anemia, loss of libido and potency. The role of salvage radiotherapy may offer local control, however long term efficacy has yet to be determined. In a recent series, only 50% of the patients were controlled for a mean of four years with salvage radiotherapy. Salvage prostatectomy has the advantage of providing excellent local control and even a cure if the cancer is confined to the prostate or within the surrounding periprostatic tissue. Historically, salvage prostatectomy is technically demanding and fraught with higher complications. In one large series

  2. Self-pinch focusing experiments performed on the KALIF accelerator using the Bappl diode

    International Nuclear Information System (INIS)

    Experiments using the Bappl diode with a subdivided beam drift section were performed on the KALIF accelerator with the objective to investigate the generation of net currents and their influence on the focusing properties of the extracted proton beam. The generation of net currents up to 50% of the diode current was observed for argon gas pressures below 0.1 mbar in the second drift section. The differences in the time histories of various net current monitors might be related to a radial dependency of the net current densities in the beam. A comparison of the focusing properties investigated in shots with and without current neutralization showed only small differences. No enhancement of the power density related to self-pinch effects was found. However, the possibility of beam propagation over a short vacuum distance allows the use of a backlighter target required for laser absorption spectroscopy. (author). 4 figs., 4 refs

  3. Efficiency of drug delivery enhanced by acoustic pressure during blood–brain barrier disruption induced by focused ultrasound

    Directory of Open Access Journals (Sweden)

    Yang FY

    2012-05-01

    Full Text Available Feng-Yi Yang, Pei-Yi LeeDepartment of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, TaiwanPurpose: We evaluated the delivery efficiency of intravenously injected large molecular agents, before and after disruption of the blood–brain barrier (BBB-D, induced by focused ultrasound (FUS using various acoustic parameters.Materials and methods: Male Sprague-Dawley rats were injected intravenously with Evans blue (EB before or after BBB-D induction by pulsed FUS. We used a 1.0 MHz pulsed FUS with four acoustic power settings and an ultrasound contrast agent (UCA at four different doses to induce BBB-D resulting from cavitation. The permeability of the BBB was assessed quantitatively based on the extravasation of EB. Contrast enhanced magnetic resonance imaging (MRI was used to monitor the gadolinium deposition associated with FUS. Histological analysis was performed to examine tissue damage.Results: The accumulation of EB in rat brain was found to be dependent on acoustic power and UCA dosage, regardless of whether EB administration occurred before or after FUS-induced BBB-D. Administration of EB followed by sonication resulted in greater EB extravasation than that for rats subjected to sonication prior to EB injection. To reduce tissue damage, EB extravasation was enhanced by first administering EB by intravenous injection, followed by sonication at reduced acoustic power or UCA dosage. The normalized signal intensity change in rat brains that received the same dose of UCA and sonicated after gadolinium injection was significantly greater than in rats undergoing sonication followed by gadolinium administration. Moreover, contrast enhanced MRI showed a more precise distribution of gadolinium in the brain when gadolinium was administered before sonication.Conclusion: We demonstrated that a compound administered prior to sonication treatment promotes extravasation of the sonicated region. Thus, it is possible to

  4. Ultrasound accelerated Claisen-Schmidt condensation: A green route to chalcones

    Energy Technology Data Exchange (ETDEWEB)

    Calvino, V. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9. E-28040 Madrid (Spain); Picallo, M. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9. E-28040 Madrid (Spain); Lopez-Peinado, A.J. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9. E-28040 Madrid (Spain); Martin-Aranda, R.M. [Dpto. de Quimica Inorganica y Quimica Tecnica, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), C/Senda del Rey, 9. E-28040 Madrid (Spain)]. E-mail: rmartin@ccia.uned.es; Duran-Valle, C.J. [Dpto. de Quimica Inorganica, Facultad de Ciencias, Universidad de Extremadura, Avenida de Elvas s/n., 06071 Badajoz (Spain)

    2006-06-30

    Chalcones have been synthesized under sonochemical irradiation by Claisen-Schmidt condensation between benzaldehyde and acetophenone. Two basic activated carbons (Na and Cs-Norit) have been used as catalysts. The effect of the ultrasound activation has been studied. A substantial enhancing effect in the yield was observed when the carbon catalyst was activated under ultrasonic waves. This 'green' method (combination of alkaline-doped carbon catalyst and ultrasound waves) has been applied to the synthesis of several chalcones with antibacterial properties achieving, in all cases, excellent activities and selectivities. A comparative study under non-sonic activation has showed that the yields are lower in silent conditions, indicating that the sonication exerts a positive effect on the activity of the catalyst. Cs-doped carbon is presented as the optimum catalyst, giving excellent activity for this type of condensation. Cs-Norit carbon catalyst can compete with the traditional NaOH/EtOH when the reaction is carried out under ultrasounds. The role of solvent in this reaction was studied with ethanol. High conversion was obtained in absence of solvent. The carbons were characterized by thermal analysis, nitrogen adsorption and X-ray photoelectron spectroscopy.

  5. Therapeutic response assessment of high intensity focused ultrasound therapy for uterine fibroid: Utility of contrast-enhanced ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Xiaodong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: zhouxd@fmmu.edu.cn; Ren Xiaolong [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)]. E-mail: renxiaolong70@hotmail.com; Zhang Jun [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); He Guangbin [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zheng Minjuan [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Tian Xue [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Li Li [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhu Ting [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Zhang Min [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Wang Lei [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China); Luo Wen [Department of Ultrasonography, Xijing Hospital, Fourth Military Medical University, No. 17 West Changle Road, Xi' an 710032 (China)

    2007-05-15

    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.

  6. Treatment of hepatic tumors by thermal versus mechanical effects of pulsed high intensity focused ultrasound in vivo

    Science.gov (United States)

    Peng, Song; Zhou, Ping; He, Wei; Liao, Manqiong; Chen, Lili; Ma, C.-M.

    2016-09-01

    The purpose of this study is to comparatively assess the thermal versus mechanical effects of pulsed high intensity focused ultrasound (HIFU) treatment on hepatic tumors in vivo. Forty-five rabbits with hepatic VX2 tumors were randomly separated into three groups (15 animals per group) before HIFU ablation. The total HIFU energy (in situ) of 1250 J was used for each tumor for three groups. In groups I and II, animals were treated with 1 MHz pulsed ultrasound at 1 Hz pulsed repetition frequency (PRF), 0.5 duty cycle (0.5 s on and 0.5 s off) and10 s duration for one spot sonication. For group II, in addition to HIFU treatment, microbubbles (SonoVue, Bracco, Milan, Italy) were injected via vein before sonication acting as a synergist. In group III, animals were treated with 1 MHz pulsed ultrasound at 10 Hz PRF, 0.1 duty cycle (0.1 s on and 0.9 s off) and 10 s duration for one sonication. The total treatment spots were calculated according to the tumor volume. Tumors were examined with contrast-enhanced computed tomography (CECT) immediately prior to and post HIFU treatment. Histopathologic assessment was performed 3 h after treatment. Our study showed that all animals tolerated the HIFU treatment well. Our data showed that mechanical HIFU could lead to controlled injury in rabbit hepatic tumors with different histological changes in comparison to thermal HIFU with or without microbubbles.

  7. Hot topics in biomedical ultrasound: ultrasound therapy and its integration with ultrasonic imaging

    Science.gov (United States)

    Everbach, E. Carr

    2005-09-01

    Since the development of biomedical ultrasound imaging from sonar after WWII, there has been a clear divide between ultrasonic imaging and ultrasound therapy. While imaging techniques are designed to cause as little change as possible in the tissues through which ultrasound propagates, ultrasound therapy typically relies upon heating or acoustic cavitation to produce a desirable therapeutic effect. Concerns over the increasingly high acoustic outputs of diagnostic ultrasound scanners prompted the adoption of the Mechanical Index (MI) and Thermal Index (TI) in the early 1990s. Therapeutic applications of ultrasound, meanwhile, have evolved from deep tissue heating in sports medicine to include targeted drug delivery, tumor and plaque ablation, cauterization via high intensity focused ultrasound (HIFU), and accelerated dissolution of blood clots. The integration of ultrasonic imaging and therapy in one device is just beginning, but the promise of improved patient outcomes is balanced by regulatory and practical impediments.

  8. Preliminary Experience Using Extracorporeal High-Intensity Focused Ultrasound For The Treatment Of Kidney And Liver Tumours

    Science.gov (United States)

    Illing, Rowland O.; Kennedy, James E.; Wu, Feng; ter Haar, Gail R.; Phillips, Rachel R.; Protheroe, Andrew S.; Middleton, Mark R.; Cranston, David W.

    2005-03-01

    High-intensity focused ultrasound (HIFU) provides a potentially non-invasive alternative to conventional therapies. We have been using the extracorporeal ultrasound-guided Model-JC Tumor Therapy System (HAIFU™ Technology Co, China) in clinical trials to evaluate the safety and feasibility of treating renal and liver tumours. 30 patients have been treated (22 liver and 8 kidney tumours), all of whom were available for adverse event reporting. Of the 22 liver tumours, 20 are evaluable for response to treatment; 14 were followed up with magnetic resonance imaging (MRI) alone, and 6 with both MRI and histological resection. Evidence of ablation was seen in 20/20 (100%) cases radiologically, and 6/6 (100%) cases histologically. Of the 8 kidney tumours treated, 7 are evaluable; 2 were followed up with MRI alone, and 5 with both MRI and histological resection. Evidence of ablation was seen in 4/7 (57%) radiologically and 1/5 (20%) histologically. Mild, moderate or severe transient pain was reported by 16 (53%), 7 (23%) and 1 (3%) patients, respectively. Superficial skin toxicity was seen in 7 patients (23%). Renal function was unaffected, and all patients were fit for discharge from hospital the day after treatment. Early results show that this technique is feasible, and carries a low morbidity.

  9. Factors influencing the ablative efficiency of high intensity focused ultrasound (HIFU) treatment for adenomyosis: A retrospective study.

    Science.gov (United States)

    Gong, Chunmei; Yang, Bin; Shi, Yarong; Liu, Zhongqiong; Wan, Lili; Zhang, Hong; Jiang, Denghua; Zhang, Lian

    2016-08-01

    Objectives The aim of this study was to investigate factors affecting ablative efficiency of high intensity focused ultrasound (HIFU) for adenomyosis. Materials and methods In all, 245 patients with adenomyosis who underwent ultrasound guided HIFU (USgHIFU) were retrospectively reviewed. All patients underwent dynamic contrast-enhanced magnetic resonance imaging (MRI) before and after HIFU treatment. The non-perfused volume (NPV) ratio, energy efficiency factor (EEF) and greyscale change were set as dependent variables, while the factors possibly affecting ablation efficiency were set as independent variables. These variables were used to build multiple regression models. Results A total of 245 patients with adenomyosis successfully completed HIFU treatment. Enhancement type on T1 weighted image (WI), abdominal wall thickness, volume of adenomyotic lesion, the number of hyperintense points, location of the uterus, and location of adenomyosis all had a linear relationship with the NPV ratio. Distance from skin to the adenomyotic lesion's ventral side, enhancement type on T1WI, volume of adenomyotic lesion, abdominal wall thickness, and signal intensity on T2WI all had a linear relationship with EEF. Location of the uterus and abdominal wall thickness also both had a linear relationship with greyscale change. Conclusion The enhancement type on T1WI, signal intensity on T2WI, volume of adenomyosis, location of the uterus and adenomyosis, number of hyperintense points, abdominal wall thickness, and distance from the skin to the adenomyotic lesion's ventral side can all be used as predictors of HIFU for adenomyosis. PMID:27385316

  10. 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.

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

    International Nuclear Information System (INIS)

    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) cm3 and (58.1 ± 45.0) cm3 respectively(P 3 (ranged between 7.7-282.9 cm3) 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/mm3 (ranged between 0.9-32.1 J/mm3). 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 make

  12. Focused ultrasound treatment of abscesses induced by methicillin resistant Staphylococcus aureus: Feasibility study in a mouse model

    Energy Technology Data Exchange (ETDEWEB)

    Rieck, Birgit [Thunder Bay Regional Research Institute, Thunder Bay, Ontario P7B6V4 (Canada); Bates, David; Pichardo, Samuel, E-mail: spichard@lakeheadu.ca, E-mail: lcuriel@lakeheadu.ca; Curiel, Laura, E-mail: spichard@lakeheadu.ca, E-mail: lcuriel@lakeheadu.ca [Thunder Bay Regional Research Institute, Thunder Bay, Ontario P7B6V4, Canada and Lakehead University, Thunder Bay, Ontario P7B6V4 (Canada); Zhang, Kunyan [Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta T2N 1N4 (Canada); Escott, Nicholas [Department of Pathology, Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario P7B 6V4 (Canada); Mougenot, Charles [Philips Healthcare, Ontario L6C 2S3 (Canada)

    2014-06-15

    Purpose: To study the therapeutic effect of focused ultrasound on abscesses induced by methicillin-resistantStaphylococcus aureus (MRSA). MRSA is a major nosocomial pathogen where immunocompromised patients are prone to develop infections that are less and less responsive to regular treatments. Because of its capability to induce a rise of temperature at a very precise location, the use of focused ultrasound represents a considerable opportunity for therapy of localized MRSA-related infections. Methods: 50μl of MRSA strain USA400 bacteria suspension at a concentration of 1.32 ± 0.5 × 10{sup 5} colony forming units (cfu)/μl was injected subcutaneously in the left flank of BALB/c mice. An abscess of 6 ± 2 mm in diameter formed after 48 h. A transducer operating at 3 MHz with a focal length of 50 mm and diameter of 32 mm was used to treat the abscess. The focal point was positioned 2 mm under the skin at the abscess center. Forty-eight hours after injection four ultrasound exposures of 9 s each were applied to each abscess under magnetic resonance imaging guidance. Each exposure was followed by a 1 min pause. These parameters were based on preliminary experiments to ensure repetitive accurate heating of the abscess. Real-time estimation of change of temperature was done using water-proton resonance frequency and a communication toolbox (matMRI) developed inhouse. Three experimental groups of animals each were tested: control, moderate temperature (MT), and high temperature (HT). MT and HT groups reached, respectively, 52.3 ± 5.1 and 63.8 ± 7.5 °C at the end of exposure. Effectiveness of the treatment was assessed by evaluating the bacteria amount of the treated abscess 1 and 4 days after treatment. Myeloperoxidase (MPO) assay evaluating the neutrophil amount was performed to assess the local neutrophil recruitment and the white blood cell count was used to evaluate the systemic inflammatory response after focused ultrasound treatment. Results: Macroscopic

  13. Ultrasound pregnancy

    Science.gov (United States)

    Pregnancy sonogram; Obstetric ultrasonography; Obstetric sonogram; Ultrasound - pregnancy; IUGR - ultrasound; Intrauterine growth - ultrasound; Polyhydramnios - ultrasound; Oligohydramnios - ultrasound; ...

  14. Cavitation-induced damage in soft tissue phantoms by focused ultrasound bursts

    Science.gov (United States)

    Movahed, Pooya; Kreider, Wayne; Maxwell, Adam D.; Bailey, Michael R.; Hutchens, Shelby B.; Freund, Jonathan B.

    2015-11-01

    Cavitation in soft tissues, similar to that in purely hydrodynamic configurations, is thought to cause tissue injury in therapeutic ultrasound treatments. Our goal is to generalize bubble dynamics models to represent this phenomenon, which we pursue experimentally with observations in tissue-mimicking polyacrylamide and agarose phantoms and semi-analytic generalization of Rayleigh-Plesset-type bubble dynamics models. The phantoms were imaged with high-speed cameras while subjected to a series of multiple pressure wave bursts, of the kind being considered specifically for burst-wave lithotripsy (BWL). The experimental observations show bubble activation at multiple sites during the initial pulses. After multiple pulses, a further onset of cavitation is observed at some new locations suggesting material failure due to fatigue under cyclic loading. A nonlinear strain-energy with strain hardening is used to represent the elasticity of the surrounding medium. Griffith's fracture criterion is then applied in order to determine the onset of material damage. The damaged material is then represented as a Newtonian fluid. By assuming that such a decrease in the fracture toughness occurs under cyclic loading, the fatigue behavior observed in the experiments can be reproduced by our model. This work was supported by NIH grant NIDDK PO1-DK043881.

  15. Evaluation of high intensity focused ultrasound ablation of prostate tumor with hyperpolarized 13C imaging biomarkers

    Science.gov (United States)

    Lee, Jessie E.; Diederich, Chris J.; Salgaonkar, Vasant A.; Bok, Robert; Taylor, Andrew G.; Kurhanewicz, John

    2015-03-01

    Real-time hyperpolarized (HP) 13C MR can be utilized during high-intensity focal ultrasound (HIFU) therapy to improve treatment delivery strategies, provide treatment verification, and thus reduce the need for more radical therapies for lowand intermediate-risk prostate cancers. The goal is to develop imaging biomarkers specific to thermal therapies of prostate cancer using HIFU, and to predict the success of thermal coagulation and identify tissues potentially sensitized to adjuvant treatment by sub-ablative hyperthermic heat doses. Mice with solid prostate tumors received HIFU treatment (5.6 MHz, 160W/cm2, 60 s), and the MR imaging follow-ups were performed on a wide-bore 14T microimaging system. 13C-labeled pyruvate and urea were used to monitor tumor metabolism and perfusion accordingly. After treatment, the ablated tumor tissue had a loss in metabolism and perfusion. In the regions receiving sub-ablative heat dose, a timedependent change in metabolism and perfusion was observed. The untreated regions behaved as a normal untreated TRAMP prostate tumor would. This promising preliminary study shows the potential of using 13C MR imaging as biomarkers of HIFU/thermal therapies.

  16. Transrectal high-intensity focused ultrasound ablation of prostate cancer: Effective treatment requiring accurate imaging

    Energy Technology Data Exchange (ETDEWEB)

    Rouviere, Olivier [Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Pavillon P Radio, Hopital Edouard Herriot, F-69437 Lyon cedex 03 (France); Universite de Lyon, Lyon F-69003 (France); Universite de Lyon 1, Faculte de Medecine Lyon Nord, Lyon F-69003 (France); INSERM, Unit 556, 151 cours Albert Thomas, F-69424 Lyon cedex 03 (France)], E-mail: Olivier.rouviere@netcourrier.com; Souchon, Remi [INSERM, Unit 556, 151 cours Albert Thomas, F-69424 Lyon cedex 03 (France)], E-mail: souchon@lyon.inserm.fr; Salomir, Rares [INSERM, Unit 556, 151 cours Albert Thomas, F-69424 Lyon cedex 03 (France)], E-mail: salomir@lyon.inserm.fr; Gelet, Albert [Hospices Civils de Lyon, Department of Urology, Pavillon P Radio, Hopital Edouard Herriot, F-69437 Lyon cedex 03 (France)], E-mail: Albert.gelet@chu-lyon.fr; Chapelon, Jean-Yves [INSERM, Unit 556, 151 cours Albert Thomas, F-69424 Lyon cedex 03 (France)], E-mail: chapelon@lyon.inserm.fr; Lyonnet, Denis [Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Pavillon P Radio, Hopital Edouard Herriot, F-69437 Lyon cedex 03 (France); Universite de Lyon, Lyon F-69003 (France); Universite de Lyon 1, Faculte de Medecine Lyon Nord, Lyon F-69003 (France); INSERM, Unit 556, 151 cours Albert Thomas, F-69424 Lyon cedex 03 (France)], E-mail: Denis.lyonnet@chu-lyon.fr

    2007-09-15

    Transrectal HIFU ablation has become a reasonable option for the treatment of localized prostate cancer in non-surgical patients, with 5-year disease-free survival similar to that of radiation therapy. It is also a promising salvage therapy of local recurrence after radiation therapy. These favourable results are partly due to recent improvements in prostate cancer imaging. However, further improvements are needed in patient selection, pre-operative localization of the tumor foci, assessment of the volume treated and early detection of recurrence. A better knowledge of the factors influencing the HIFU-induced tissue destruction and a better pre-operative assessment of them by imaging techniques should improve treatment outcome. Whereas prostate HIFU ablation is currently performed under transrectal ultrasound guidance, MR guidance with real-time operative monitoring of temperature will be available in the near future. If this technique will give better targeting and more uniform tissue destruction, its cost-effectiveness will have to be carefully evaluated. Finally, a recently reported synergistic effect between HIFU ablation and chemotherapy opens possibilities for treatment in high-risk or clinically advanced tumors.

  17. Stimulated acceleration and confinement of deuterons in focused discharges - Part II

    International Nuclear Information System (INIS)

    New methods of increasing, by a factor greater than 5, the neutron yield/shot Y/sub n/ from D-D fusion reactions in a plasma focus (PF) enhance both the D/sup +/-ion acceleration to energy values E > 1-8 MeV and the in confinement in the pinch region. Nuclear activation of C and N in the (doped) filling gas of the discharge chamber and of solid targets of C and BN bombarded by the ion beam in the direction of the electrode axis (00) confirms earlier determination of the energy spectrum of the trapped ions (dphi/sub t//dE ∞ phi/sub 0t/E/sup -m/) and of the ejected beam (dphi/sub b//dE ∞ phi/sub 0b/E/sup -m/, m = 2.5 +- 0.5 for 0.1 MeV ≤ E ≤ 3 MeV). A Thomson (parabola) spectrometer with nanosecond time resolution determines the time of emission t (E) of the beam at 00. Ion acceleration and trapping occur within the small (filamentary) elements of the magnetic field structure of the pinch, which can be dispersed on a relatively large confinement volume after the pinch disintegration. The authors find that phi/sub t//phi/sub b/ ≥ 10-10/sup 3/ for E ≤ 1 MeV, depending on Y/sub n/

  18. 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

  19. 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

    International Nuclear Information System (INIS)

    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

  20. Clinical Predictors of Long-term Success in Ultrasound-guided High-intensity Focused Ultrasound Ablation Treatment for Adenomyosis: A Retrospective Study.

    Science.gov (United States)

    Liu, Xin; Wang, Wei; Wang, Yang; Wang, Yuexiang; Li, Qiuyang; Tang, Jie

    2016-01-01

    The long-term outcomes of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation treatment for adenomyosis and the relevant factors affecting the durability of symptom relief were assessed in this study.A total of 230 women with adenomyosis who were treated with USgHIFU ablation between January 2007 and December 2013 were retrospectively analyzed. The contrast-enhanced ultrasonography (CEUS) was performed immediately after the treatment to evaluate the ablation effect, and the nonperfused volume (NPV) ratio was then calculated. Regular follow-up was conducted and the visual analog scale (VAS) score was used to assess the changes in dysmenorrhea. The effect of treatment was evaluated after an average follow-up length of 3 months and the factors affecting clinical success and symptom relapse were identified.Of the 230 treated patients, 208 (90.4%) were followed up regularly, with a median follow-up length of 40 months (range, 18-94 months). Mean value of the NPV ratio calculated immediately after the treatment was 57.4 ± 24.4%. Varying degrees of symptomatic relief of dysmenorrhea based on the VAS scores were observed in 173 (83.2%) patients and 71.0% of the patients were asymptomatic during follow-up. Women with higher NPV ratio (OR = 0.964, 95% CI = 0.947-0.982, P = 0.000) and older age (OR = 0.342, 95% CI = 0.143-0.819, P = 0.016) were more likely to achieve clinical success. Dysmenorrhea recurred in 45 (26%) out of 173 cases; the median recurrence time was 12 months after treatment. The lower BMI (OR = 1.221, 95% CI = 1.079-1.381, P = 0.001) and the higher acoustic power (OR = 0.992, 95% CI = 0.986-0.998, P = 0.007) were associated with less risk of relapse. Twelve of the 14 patients who were retreated by USgHIFU ablation after experiencing dysmenorrhea recurrence achieved clinical success.USgHIFU ablation is an effective uterus-conserving treatment for symptomatic adenomyosis with an acceptable

  1. Stimulated acceleration and confinement of deuterons in focused discharges - Part I

    International Nuclear Information System (INIS)

    Acceleration and confinement of megaelectronvolt D/sup +/ ions in the plasma focus (PF) are analyzed in terms of the observed energy spectrum of the ejected ions and of the energy spectrum of the D-D neutrons from which the trapped-ion spectrum is derived. The current distribution in the interelectrode gap can be modified by field distortion elements (FDE's) which increase the fraction of the total electrode current flowing in the pinch. An optimized FDE increases the observed maximum value, Max Y/sub n/, and the mean value Y-bar/sub n/, of the observed D-D neutron yield per shot Y/sub n/ by a factor ≥ 3. The ejected-ion spectrum is determined by three dependent methods (Thomson spectrometers, high-resolution magnetic analyzer/filters, and Faraday cups)

  2. Stimulated acceleration and confinement of deuterons in focused discharges - Part I

    Energy Technology Data Exchange (ETDEWEB)

    Nardi, V.; Bortolotti, A.; Brzosko, J.S.; Esper, M.; Luo, C.M.; Pedrielli, F.; Powell, C.; Zeng, D.

    1988-06-01

    Acceleration and confinement of megaelectronvolt D/sup +/ ions in the plasma focus (PF) are analyzed in terms of the observed energy spectrum of the ejected ions and of the energy spectrum of the D-D neutrons from which the trapped-ion spectrum is derived. The current distribution in the interelectrode gap can be modified by field distortion elements (FDE's) which increase the fraction of the total electrode current flowing in the pinch. An optimized FDE increases the observed maximum value, Max Y/sub n/, and the mean value Y-bar/sub n/, of the observed D-D neutron yield per shot Y/sub n/ by a factor greater than or equal to 3. The ejected-ion spectrum is determined by three dependent methods (Thomson spectrometers, high-resolution magnetic analyzer/filters, and Faraday cups).

  3. Design, simulation and construction of quadrupole magnets for focusing electron beam in powerful industrial electron accelerator

    Directory of Open Access Journals (Sweden)

    S KH Mousavi

    2015-09-01

    Full Text Available In this paper the design and simulation of quadrupole magnets and electron beam optical of that by CST Studio code has been studied. Based on simulation result the magnetic quadrupole has been done for using in beam line of first Iranian powerful electron accelerator. For making the suitable magnetic field the effects of material and core geometry and coils current variation on quadrupole magnetic field have been studied. For test of quadrupole magnet the 10 MeV beam energy and 0.5 pi mm mrad emittance of input beam has been considered. We see the electron beam through the quadrupole magnet focus in one side and defocus in other side. The optimum of distance between two quadrupole magnets for low emittance have been achieved. The simulation results have good agreement with experimental results

  4. Performance of solenoids vs. quadrupoles in focusing and energy selection of laser accelerated protons

    CERN Document Server

    Hofmann, Ingo

    2013-01-01

    Using laser accelerated protons or ions for various applications - for example in particle therapie or short-pulse radiographic diagnostics - requires an effective method of focusing and energy selection. We derive an analytical scaling for the performance of a solenoid compared with a doublet/triplet as function of the energy, which is confirmed by TRACEWIN simulations. The scaling shows that above a few MeV a solenoid needs to be pulsed or super-conducting, whereas the quadrupoles can remain conventional. The transmission of the triplet is found only 25% lower than that of the equivalent solenoid. Both systems are equally suitable for energy selection based on their chromatic effect as is shown using an initial distribution following the RPA simulation model by Yan et al.\\cite{yan2009}.

  5. Efficient generation of cavitation bubbles and reactive oxygen species using triggered high-intensity focused ultrasound sequence for sonodynamic treatment

    Science.gov (United States)

    Yasuda, Jun; Yoshizawa, Shin; Umemura, Shin-ichiro

    2016-07-01

    Sonodynamic treatment is a method of treating cancer using reactive oxygen species (ROS) generated by cavitation bubbles in collaboration with a sonosensitizer at a target tissue. In this treatment method, both localized ROS generation and ROS generation with high efficiency are important. In this study, a triggered high-intensity focused ultrasound (HIFU) sequence, which consists of a short, extremely high intensity pulse immediately followed by a long, moderate-intensity burst, was employed for the efficient generation of ROS. In experiments, a solution sealed in a chamber was exposed to a triggered HIFU sequence. Then, the distribution of generated ROS was observed by the luminol reaction, and the amount of generated ROS was quantified using KI method. As a result, the localized ROS generation was demonstrated by light emission from the luminol reaction. Moreover, it was demonstrated that the triggered HIFU sequence has higher efficiency of ROS generation by both the KI method and the luminol reaction emission.

  6. Application of Focused Ultrasound-Assisted Extraction to the Determination of Persistent Organic Pollutants (POPs) in Soil Samples.

    Science.gov (United States)

    Flores-Ramírez, R; Medellín-Garibay, S E; Castillo, C G; Ilizaliturri-Hernández, C A; Zuki-Orozco, B A; Batres-Esquivel, L; Díaz-Barriga, F

    2015-08-01

    A simple and rapid focused ultrasound extraction (FU) based method is presented for the determination of persistent organic pollutants (POPs) in soil using a gas chromatography coupled to a mass detector with electron impact ionization. The main experimental parameters affecting the FU step have been optimized by applying a PERMANOVA and PCO analysis allowing us to obtain a maximum amount of information with a minimum number of assays. The limits of detection for POPs fell within the 0.9-6.8 ng/g d.w. interval; a linear method was used with correlation coefficients (r) higher than 0.99. Recovery percentages at low concentrations (25 ng/g d.w.) were 75.8%-110%, and at high concentrations (75 ng/g d.w.) 82.3%-109%; the evaluated precision as RSD% of repeatability and reproducibility were within a range of 0.5%-11% and 0.3%-18%, respectively.

  7. Fundamental analysis and ex vivo validation of thermal lesion mapping using harmonic motion imaging for focused ultrasound (HMIFU)

    Science.gov (United States)

    Hou, Gary Y.; Luo, Jianwen; Maleke, Caroline; Vappou, Jonathan; Marquet, Fabrice; Konofagou, Elisa E.

    2012-10-01

    Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a novel high-intensity focused ultrasound (HIFU) therapy monitoring method with feasibilities demonstrated in vitro, ex vivo and in vivo. Its principle is based on Amplitude-modulated (AM) - Harmonic Motion Imaging (HMI), an oscillatory radiation force used for imaging the tissue mechanical response during thermal ablation. In this study, a theoretical framework of HMIFU is presented, comprising a customized nonlinear wave propagation model, a finite-element (FE) analysis module, and an image-formation model. The objective of this study is to develop such a framework in order to 1) assess the fundamental performance of HMIFU in detecting HIFU lesions based on the change in tissue apparent elasticity, i.e., the increasing Young's modulus, and the HIFU lesion size with respect to the HIFU exposure time and 2) validate the simulation findings ex vivo. The same HMI and HMIFU parameters as in the experimental studies were used, i.e., 4.5-MHz HIFU frequency and 25-Hz AM frequency. For a lesion-to-background Young's modulus ratio of 3, 6, and 9, the estimated HMI displacement ratios were equal to 1.65, 3.19, 4.59, respectively. In experiments, the HMI displacement followed a similar increasing trend of 1.19, 1.28, 1.78 at 10-s, 20-s, and 30-s HIFU exposure, respectively. In addition, moderate agreement in lesion size growth was also found in both simulations (16.2, 73.1 and 334.7 mm2) and experiments (26.2, 94.2 and 206.2 mm2). Therefore, the feasibility of HMIFU for HIFU lesion detection based on the underlying tissue elasticity changes was verified through the developed theoretical framework, i.e., validation of the fundamental performance of the HMIFU system for lesion detection, localization and quantification, was demonstrated both theoretically and ex vivo.

  8. Histological and biochemical analysis of mechanical and thermal bioeffects in boiling histotripsy lesions induced by high intensity focused ultrasound.

    Science.gov (United States)

    Wang, Yak-Nam; Khokhlova, Tatiana; Bailey, Michael; Hwang, Joo Ha; Khokhlova, Vera

    2013-03-01

    Recent studies have shown that shockwave heating and millisecond boiling in high-intensity focused ultrasound fields can result in mechanical fractionation or emulsification of tissue, termed boiling histotripsy. Visual observations of the change in color and contents indicated that the degree of thermal damage in the emulsified lesions can be controlled by varying the parameters of the exposure. The goal of this work was to examine thermal and mechanical effects in boiling histotripsy lesions using histologic and biochemical analysis. The lesions were induced in ex vivo bovine heart and liver using a 2-MHz single-element transducer operating at duty factors of 0.005-0.01, pulse durations of 5-500 ms and in situ shock amplitude of 73 MPa. Mechanical and thermal damage to tissue was evaluated histologically using conventional staining techniques (hematoxylin and eosin, and nicotinamide adenine dinucleotide-diaphorase). Thermal effects were quantified by measuring denaturation of salt soluble proteins in the treated region. According to histologic analysis, the lesions that visually appeared as a liquid contained no cellular structures larger than a cell nucleus and had a sharp border of one to two cells. Both histologic and protein analysis showed that lesions obtained with short pulses (thermal damage. Increasing the pulse duration resulted in an increase in thermal damage. However, both protein analysis and nicotinamide adenine dinucleotide-diaphorase staining showed less denaturation than visually observed as whitening of tissue. The number of high-intensity focused ultrasound pulses delivered per exposure did not change the lesion shape or the degree of thermal denaturation, whereas the size of the lesion showed a saturating behavior suggesting optimal exposure duration. This study confirmed that boiling histotripsy offers an effective, predictable way to non-invasively fractionate tissue into sub-cellular fragments with or without inducing thermal damage.

  9. Feasibility of real-time treatment feedback using novel filter for eliminating therapeutic ultrasound noise with high-speed ultrasonic imaging in ultrasound-guided high-intensity focused ultrasound treatment

    Science.gov (United States)

    Takagi, Ryo; Jimbo, Hayato; Iwasaki, Ryosuke; Tomiyasu, Kentaro; Yoshizawa, Shin; Umemura, Shin-ichiro

    2016-07-01

    In the conventional ultrasonic monitoring of high-intensity focused ultrasound (HIFU) treatment, a significant interval between HIFU shots is required when monitoring target tissue to avoid interference between HIFU noise and RF echo signals. In our previous study, a new filtering method to eliminate only HIFU noise while maintaining tissue signals intact was proposed, and it was shown that the thermal coagulation could be detected during simultaneous HIFU irradiation through off-line processing. In this study, the filtering method and a real-time coagulation detection algorithm were implemented in an ultrasound imaging system, whose use for sequential exposure with multiple foci was demonstrated similarly to a commercial HIFU ablation system. The coagulation was automatically detected by the proposed method during real-time simultaneous HIFU irradiation, and the HIFU exposure time was controlled according to the changes in the tissue. The results imply that ultrasonic monitoring with the filtering and detection methods is useful for true real-time detection of changes in the tissue due to thermal coagulation during HIFU exposure.

  10. Coagulation and ablation patterns of high-intensity focused ultrasound on a tissue-mimicking phantom and cadaveric skin.

    Science.gov (United States)

    Kim, Hee-Jin; Kim, Han Gu; Zheng, Zhenlong; Park, Hyoun Jun; Yoon, Jeung Hyun; Oh, Wook; Lee, Cheol Woo; Cho, Sung Bin

    2015-12-01

    High-intensity focused ultrasound (HIFU) can be applied noninvasively to create focused zones of tissue coagulation on various skin layers. We performed a comparative study of HIFU, evaluating patterns of focused tissue coagulation and ablation upon application thereof. A tissue-mimicking (TM) phantom was prepared with bovine serum albumin and polyacrylamide hydrogel to evaluate the geometric patterns of HIFU-induced thermal injury zones (TIZs) for five different HIFU devices. Additionally, for each device, we investigated histologic patterns of HIFU-induced coagulation and ablation in serial sections of cadaveric skin of the face and neck. All HIFU devices generated remarkable TIZs in the TM phantom, with different geometric values of coagulation for each device. Most of the TIZs seemed to be separated into two or more tiny parts. In cadaveric skin, characteristic patterns of HIFU-induced ablation and coagulation were noted along the mid to lower dermis at the focal penetration depth of 3 mm and along subcutaneous fat to the superficial musculoaponeurotic system or the platysma muscle of the neck at 4.5 mm. Additionally, remarkable pre-focal areas of tissue coagulation were observed in the upper and mid dermis at the focal penetration depth of 3 mm and mid to lower dermis at 4.5 mm. For five HIFU devices, we outlined various patterns of HIFU-induced TIZ formation along pre-focal, focal, and post-focal areas of TM phantom and cadaveric skin of the face and neck. PMID:26341380

  11. Influence of Skin and Subcutaneous Tissue on High-Intensity Focused Ultrasound Beam: Experimental Quantification and Numerical Modeling.

    Science.gov (United States)

    Grisey, Anthony; Heidmann, Marc; Letort, Veronique; Lafitte, Pauline; Yon, Sylvain

    2016-10-01

    High-intensity focused ultrasound (HIFU) enables the non-invasive thermal ablation of tumors. However, numerical simulations of the treatment remain complex and difficult to validate in clinically relevant situations. In this context, needle hydrophone measurements of the acoustic field downstream of seven rabbit tissue layers comprising skin, subcutaneous fat and muscle were performed in different geometrical configurations. Increasing curvature and thickness of the sample were found to decrease the focusing of the beam: typically, a curvature of 0.05 mm(-1) decreased the maximum pressure by 45% and doubled the focal area. A numerical model based on k-Wave Toolbox was found to be in very good agreement with the reported measurements. It was used to extrapolate the effect of the superficial tissues on peak positive and peak negative pressure at focus, which affects both cavitation and target heating. The shape of the interface was found to have a strong influence on the values, and it is therefore an important parameter to monitor or to control in the clinical practice. This also highlights the importance of modeling realistic configurations when designing treatment procedures. PMID:27471120

  12. Performance of solenoids versus quadrupoles in focusing and energy selection of laser accelerated protons

    Science.gov (United States)

    Hofmann, Ingo

    2013-04-01

    Using laser accelerated protons or ions for various applications—for example in particle therapy or short-pulse radiographic diagnostics—requires an effective method of focusing and energy selection. We derive an analytical scaling for the performance of a solenoid compared with a doublet/triplet as function of the energy, which is confirmed by TRACEWIN simulations. Generally speaking, the two approaches are equivalent in focusing capability, if parameters are such that the solenoid length approximately equals its diameter. The scaling also shows that this is usually not the case above a few MeV; consequently, a solenoid needs to be pulsed or superconducting, whereas the quadrupoles can remain conventional. It is also important that the transmission of the triplet is found only 25% lower than that of the equivalent solenoid. Both systems are equally suitable for energy selection based on their chromatic effect as is shown using an initial distribution following the RPA simulation model by Yan et al. [Phys. Rev. Lett. 103, 135001 (2009PRLTAO0031-900710.1103/PhysRevLett.103.135001].

  13. A FOCUSED TRANSPORT APPROACH TO THE TIME-DEPENDENT SHOCK ACCELERATION OF SOLAR ENERGETIC PARTICLES AT A FAST TRAVELING SHOCK

    International Nuclear Information System (INIS)

    Some of the most sophisticated models for solar energetic particle (SEP) acceleration at coronal mass ejection driven shocks are based on standard diffusive shock acceleration theory. However, this theory, which only applies when SEP pitch-angle anisotropies are small, might have difficulty in describing first-order Fermi acceleration or the shock pre-heating and injection of SEPs into first-order Fermi acceleration accurately at lower SEP speeds where SEP pitch-angle anisotropies upstream near the shock can be large. To avoid this problem, we use a time-dependent focused transport model to reinvestigate first-order Fermi acceleration at planar parallel and quasi-parallel spherical traveling shocks between the Sun and Earth with high shock speeds associated with rare extreme gradual SEP events. The focused transport model is also used to investigate and compare three different shock pre-heating mechanisms associated with different aspects of the nonuniform cross-shock solar wind flow, namely, the convergence of the flow (adiabatic compression), the shear tensor of the flow, and the acceleration of the flow, and a fourth shock pre-heating mechanism associated with the cross-shock electric field, to determine which pre-heating mechanism contributes the most to injecting shock pre-heated source particles into the first-order Fermi acceleration process. The effects of variations in traveling shock conditions, such as increasing shock obliquity and shock slowdown, and variations in the SEP source with increasing shock distance from the Sun on the coupled processes of shock pre-heating, injection, and first-order Fermi acceleration are analyzed. Besides the finding that the cross-shock acceleration of the solar wind flow yields the dominant shock pre-heating mechanism at high shock speeds, we find that first-order Fermi acceleration at fast traveling shocks differs in a number of respects from the predictions and assumptions of standard steady-state diffusive shock

  14. A FOCUSED TRANSPORT APPROACH TO THE TIME-DEPENDENT SHOCK ACCELERATION OF SOLAR ENERGETIC PARTICLES AT A FAST TRAVELING SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    Le Roux, J. A.; Webb, G. M. [Department of Physics, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2012-02-10

    Some of the most sophisticated models for solar energetic particle (SEP) acceleration at coronal mass ejection driven shocks are based on standard diffusive shock acceleration theory. However, this theory, which only applies when SEP pitch-angle anisotropies are small, might have difficulty in describing first-order Fermi acceleration or the shock pre-heating and injection of SEPs into first-order Fermi acceleration accurately at lower SEP speeds where SEP pitch-angle anisotropies upstream near the shock can be large. To avoid this problem, we use a time-dependent focused transport model to reinvestigate first-order Fermi acceleration at planar parallel and quasi-parallel spherical traveling shocks between the Sun and Earth with high shock speeds associated with rare extreme gradual SEP events. The focused transport model is also used to investigate and compare three different shock pre-heating mechanisms associated with different aspects of the nonuniform cross-shock solar wind flow, namely, the convergence of the flow (adiabatic compression), the shear tensor of the flow, and the acceleration of the flow, and a fourth shock pre-heating mechanism associated with the cross-shock electric field, to determine which pre-heating mechanism contributes the most to injecting shock pre-heated source particles into the first-order Fermi acceleration process. The effects of variations in traveling shock conditions, such as increasing shock obliquity and shock slowdown, and variations in the SEP source with increasing shock distance from the Sun on the coupled processes of shock pre-heating, injection, and first-order Fermi acceleration are analyzed. Besides the finding that the cross-shock acceleration of the solar wind flow yields the dominant shock pre-heating mechanism at high shock speeds, we find that first-order Fermi acceleration at fast traveling shocks differs in a number of respects from the predictions and assumptions of standard steady-state diffusive shock

  15. Stimulated acceleration and confinement of deuterons in focused discharges - Part II

    Energy Technology Data Exchange (ETDEWEB)

    Nardi, V.; Bilbao, L.; Brzosko, J.S.; Powell, C.; Zeng, D.; Bortolotti, A.; Mezzetti, F.; Robouch, B.V.

    1988-06-01

    New methods of increasing, by a factor greater than 5, the neutron yield/shot Y/sub n/ from D-D fusion reactions in a plasma focus (PF) enhance both the D/sup +/-ion acceleration to energy values E > 1-8 MeV and the in confinement in the pinch region. Nuclear activation of C and N in the (doped) filling gas of the discharge chamber and of solid targets of C and BN bombarded by the ion beam in the direction of the electrode axis (0/sup 0/) confirms earlier determination of the energy spectrum of the trapped ions (dphi/sub t//dE infinity phi/sub 0t/E/sup -m/) and of the ejected beam (dphi/sub b//dE infinity phi/sub 0b/E/sup -m/, m = 2.5 +- 0.5 for 0.1 MeV less than or equal to E less than or equal to 3 MeV). A Thomson (parabola) spectrometer with nanosecond time resolution determines the time of emission t (E) of the beam at 0/sup 0/. Ion acceleration and trapping occur within the small (filamentary) elements of the magnetic field structure of the pinch, which can be dispersed on a relatively large confinement volume after the pinch disintegration. The authors find that phi/sub t//phi/sub b/ greater than or equal to 10-10/sup 3/ for E less than or equal to 1 MeV, depending on Y/sub n/.

  16. Non-invasive Measurement of Thermal Diffusivity Using High-Intensity Focused Ultrasound and Through-Transmission Ultrasonic Imaging.

    Science.gov (United States)

    Yeshurun, Lilach; Azhari, Haim

    2016-01-01

    Thermal diffusivity at the site ablated by high-intensity focused ultrasound (HIFU) plays an important role in the final therapeutic outcome, as it influences the temperature's spatial and temporal distribution. Moreover, as tissue thermal diffusivity is different in tumors as compared with normal tissue, it could also potentially be used as a new source of imaging contrast. The aim of this study was to examine the feasibility of combining through-transmission ultrasonic imaging and HIFU to estimate thermal diffusivity non-invasively. The concept was initially evaluated using a computer simulation. Then it was experimentally tested on phantoms made of agar and ex vivo porcine fat. A computerized imaging system combined with a HIFU system was used to heat the phantoms to temperatures below 42°C to avoid irreversible damage. Through-transmission scanning provided the time-of-flight values in a region of interest during its cooling process. The time-of-flight values were consequently converted into mean values of speed of sound. Using the speed-of-sound profiles along with the developed model, we estimated the changes in temperature profiles over time. These changes in temperature profiles were then used to calculate the corresponding thermal diffusivity of the studied specimen. Thermal diffusivity for porcine fat was found to be lower by one order of magnitude than that obtained for agar (0.313×10(-7)m(2)/s vs. 4.83×10(-7)m(2)/s, respectively, p < 0.041). The fact that there is a substantial difference between agar and fat implies that non-invasive all-ultrasound thermal diffusivity mapping is feasible. The suggested method may particularly be suitable for breast scanning. PMID:26489364

  17. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    Energy Technology Data Exchange (ETDEWEB)

    Mancuso, Frederico José Neves, E-mail: frederico.mancuso@grupofleury.com.br [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Disciplina de Medicina de Urgência - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Siqueira, Vicente Nicoliello; Moisés, Valdir Ambrósio [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Gois, Aécio Flavio Teixeira [Disciplina de Medicina de Urgência - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Paola, Angelo Amato Vincenzo de; Carvalho, Antonio Carlos Camargo; Campos, Orlando [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil)

    2014-12-15

    Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ischemic changes in the electrocardiography or fever were excluded. A focused echocardiography with GE Vscan equipment was performed after the initial evaluation in the emergency room. Cardiac chambers dimensions, left and right ventricular systolic function, intracardiac flows with color, pericardium, and aorta were evaluated. The mean age was 61 ± 17 years old. The patient complaint was chest pain in 51 patients, dyspnea in 32 patients, arrhythmia to evaluate the left ventricular function in ten patients, hypotension/dizziness in five patients and edema in one patient. In 28 patients, the focused echocardiography allowed to confirm the initial diagnosis: 19 patients with heart failure, five with acute coronary syndrome, two with pulmonary embolism and two patients with cardiac tamponade. In 17 patients, the echocardiography changed the diagnosis: ten with suspicious of heart failure, two with pulmonary embolism suspicious, two with hypotension without cause, one suspicious of acute coronary syndrome, one of cardiac tamponade and one of aortic dissection. The focused echocardiography with pocket-size equipment in the emergency care may allow a prompt diagnosis and, consequently, an earlier initiation of the therapy.

  18. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    International Nuclear Information System (INIS)

    Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ischemic changes in the electrocardiography or fever were excluded. A focused echocardiography with GE Vscan equipment was performed after the initial evaluation in the emergency room. Cardiac chambers dimensions, left and right ventricular systolic function, intracardiac flows with color, pericardium, and aorta were evaluated. The mean age was 61 ± 17 years old. The patient complaint was chest pain in 51 patients, dyspnea in 32 patients, arrhythmia to evaluate the left ventricular function in ten patients, hypotension/dizziness in five patients and edema in one patient. In 28 patients, the focused echocardiography allowed to confirm the initial diagnosis: 19 patients with heart failure, five with acute coronary syndrome, two with pulmonary embolism and two patients with cardiac tamponade. In 17 patients, the echocardiography changed the diagnosis: ten with suspicious of heart failure, two with pulmonary embolism suspicious, two with hypotension without cause, one suspicious of acute coronary syndrome, one of cardiac tamponade and one of aortic dissection. The focused echocardiography with pocket-size equipment in the emergency care may allow a prompt diagnosis and, consequently, an earlier initiation of the therapy

  19. Radiation force on absorbing targets and power measurements of a high intensity focused ultrasound (HIFU) source

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the analytic expressions for the radiated field of a circular concave piston given by Hasegawa et al.,an integral for calculation of the radiation force on a plane absorbing target in a spherically focused field is derived.A general relation between acoustic power P and normal radiation force Fn is obtained under the condition of kr 1.Numerical computation is carried out by using the symbolic computation program for practically focused sources and absorbing circular targets.The results show that,for a given source,there is a range of target positions where the radiation force is independent of the target’s position under the assumption that the contribution of the acoustic field behind the target to the radiation force can be neglected.The experiments are carried out and confirm that there is a range of target positions where the measured radiation force is basically independent of the target’s position even at high acoustic power (up to 700 W).It is believed that when the radiation force method is used to measure the acoustic power radiated from a focused source,the size of the target must be selected in such a way that no observable sound can be found in the region behind the target.

  20. Duplex ultrasound

    Science.gov (United States)

    Vascular ultrasound; Peripheral vascular ultrasound ... A duplex ultrasound combines traditional ultrasound with Doppler ultrasound . Traditional ultrasound uses sound waves that bounce off blood vessels to create ...

  1. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    Directory of Open Access Journals (Sweden)

    Frederico José Neves Mancuso

    2014-12-01

    Full Text Available Background: Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. Objective: To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. Methods: One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ischemic changes in the electrocardiography or fever were excluded. A focused echocardiography with GE Vscan equipment was performed after the initial evaluation in the emergency room. Cardiac chambers dimensions, left and right ventricular systolic function, intracardiac flows with color, pericardium, and aorta were evaluated. Results: The mean age was 61 ± 17 years old. The patient complaint was chest pain in 51 patients, dyspnea in 32 patients, arrhythmia to evaluate the left ventricular function in ten patients, hypotension/dizziness in five patients and edema in one patient. In 28 patients, the focused echocardiography allowed to confirm the initial diagnosis: 19 patients with heart failure, five with acute coronary syndrome, two with pulmonary embolism and two patients with cardiac tamponade. In 17 patients, the echocardiography changed the diagnosis: ten with suspicious of heart failure, two with pulmonary embolism suspicious, two with hypotension without cause, one suspicious of acute coronary syndrome, one of cardiac tamponade and one of aortic dissection. Conclusion: The focused echocardiography with pocket-size equipment in the emergency care may allow a prompt diagnosis and, consequently, an earlier initiation of the therapy.

  2. Low-intensity pulsed ultrasound accelerates nerve regeneration following inferior alveolar nerve transection in rats.

    Science.gov (United States)

    Sato, Mai; Motoyoshi, Mitsuru; Shinoda, Masamichi; Iwata, Koichi; Shimizu, Noriyoshi

    2016-06-01

    Inferior alveolar nerve (IAN) injury, which is frequently caused by orofacial surgery or trauma, induces sensory loss in orofacial regions innervated by the IAN. However, no effective treatment for orofacial sensory loss currently exists. We determined whether sensory loss in facial skin above the mental foramen following IAN transection was recovered by exposure of the transected IAN to low-intensity pulsed ultrasound (LIPUS). Inferior alveolar nerve transection (IANX) was performed in 7-wk-old male Sprague-Dawley rats. On day 7 after IANX, the effect of daily LIPUS (from day 0) on the transected IAN, in terms of sensitivity to mechanical stimulation of the facial skin above the mental foramen, was examined. Moreover, the number of trigeminal ganglion (TG) neurons innervating the facial skin above the mental foramen of rats with IANX treated daily with LIPUS was counted using the retrograde neurotracing technique. Daily exposure of the transected IAN to LIPUS significantly promoted recovery of the head-withdrawal threshold in response to mechanical stimulation of the facial skin above the mental foramen, and the number of TG neurons innervating the facial skin above mental foramen was significantly increased in rats with IANX treated daily with LIPUS compared with sham or LIPUS-unexposed rats. Daily treatment of stumps of the transected IAN with LIPUS facilitated morphological and functional regeneration, suggesting that LIPUS is an effective and novel therapy for IAN injury. PMID:27058986

  3. Pulsed ultrasound therapy accelerates the recovery of skeletal muscle damage induced by Bothrops jararacussu venom

    Directory of Open Access Journals (Sweden)

    J. Saturnino-Oliveira

    2012-06-01

    Full Text Available We studied the effect of pulsed ultrasound therapy (UST and antibothropic polyvalent antivenom (PAV on the regeneration of mouse extensor digitorum longus muscle following damage by Bothrops jararacussu venom. Animals (Swiss male and female mice weighing 25.0 ± 5.0 g; 5 animals per group received a perimuscular injection of venom (1 mg/kg and treatment with UST was started 1 h later (1 min/day, 3 MHz, 0.3 W/cm², pulsed mode. Three and 28 days after injection, muscles were dissected and processed for light microscopy. The venom caused complete degeneration of muscle fibers. UST alone and combined with PAV (1.0 mL/kg partially protected these fibers, whereas muscles receiving no treatment showed disorganized fascicules and fibers with reduced diameter. Treatment with UST and PAV decreased the effects of the venom on creatine kinase content and motor activity (approximately 75 and 48%, respectively. Sonication of the venom solution immediately before application decreased the in vivo and ex vivo myotoxic activities (approximately 60 and 50%, respectively. The present data show that UST counteracts some effects of B. jararacussu venom, causing structural and functional improvement of the regenerated muscle after venom injury.

  4. MR Thermometry Analysis of Sonication Accuracy and Safety Margin of Volumetric MR Imaging-guided High-Intensity Focused Ultrasound Ablation of Symptomatic Uterine Fibroids

    NARCIS (Netherlands)

    Kim, Young-sun; Trillaud, Herve; Rhim, Hyunchul; Lim, Hyo K.; Mali, Willem; Voogt, Marianne; Barkhausen, Jorg; Eckey, Thomas; Kohler, Max O.; Keserci, Bilgin; Mougenot, Charles; Sokka, Shunmugavelu D.; Soini, Jouko; Nieminen, Heikki J.

    2012-01-01

    Purpose: To evaluate the accuracy of the size and location of the ablation zone produced by volumetric magnetic resonance (MR) imaging-guided high-intensity focused ultrasound ablation of uterine fibroids on the basis of MR thermometric analysis and to assess the effects of a feedback control techni

  5. Short-time focused ultrasound hyperthermia enhances liposomal doxorubicin delivery and antitumor efficacy for brain metastasis of breast cancer

    Directory of Open Access Journals (Sweden)

    Wu SK

    2014-09-01

    Full Text Available Sheng-Kai Wu,1 Chi-Feng Chiang,1 Yu-Hone Hsu,1,4 Tzu-Hung Lin,2 Houng-Chi Liou,2 Wen-Mei Fu,2 Win-Li Lin1,3 1Institute of Biomedical Engineering, College of Medicine and College of Engineering, 2Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan; 3Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan; 4Department of Neurosurgery, Cheng-Hsin General Hospital, Taipei, Taiwan Abstract: The blood–brain/tumor barrier inhibits the uptake and accumulation of chemotherapeutic drugs. Hyperthermia can enhance the delivery of chemotherapeutic agent into tumors. In this study, we investigated the effects of short-time focused ultrasound (FUS hyperthermia on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD for brain metastasis of breast cancer. Murine breast cancer 4T1-luc2 cells expressing firefly luciferase were injected into female BALB/c mice striatum tissues and used as a brain metastasis model. The mice were intravenously injected with PLD (5 mg/kg with/without 10-minute transcranial FUS hyperthermia on day 6 after tumor implantation. The amounts of doxorubicin accumulated in the normal brain tissues and tumor tissues with/without FUS hyperthermia were measured using fluorometry. The tumor growth for the control, hyperthermia, PLD, and PLD + hyperthermia groups was measured using an IVIS spectrum system every other day from day 3 to day 11. Cell apoptosis and tumor characteristics were assessed using immunohistochemistry. Short-time FUS hyperthermia was able to significantly enhance the PLD delivery into brain tumors. The tumor growth was effectively inhibited by a single treatment of PLD + hyperthermia compared with both PLD alone and short-time FUS hyperthermia alone. Immunohistochemical examination further demonstrated the therapeutic efficacy of PLD plus short-time FUS hyperthermia for brain metastasis of breast cancer. The

  6. High intensity focused ultrasound (HIFU) for treatment of T1/T2 prostate cancer

    Science.gov (United States)

    Sanghvi, N.; Gardner, T.; Koch, M.

    2003-04-01

    This FDA approved phase I/II clinical trial is to evaluate the safety and efficacy of the Sonablate device (Focus Surgery, Inc.) for the treatment of organ confined prostate cancer. 20 patients with biopsy proven prostate cancer, Gleason biopsy results at 6 months. Quality of life was assessed using the International Prostate Symptom Score, International Impotence and Erectile Function score, and the SF-36 health survey. The mean patient age is 62.0, Gleason score of 6.18, PSA of 5.2, and prostate size 26.0 gm. Mean PSA results were 5.62, 44, 20, 1.68, 0.87, and 0.44 ng/ml at screening, 48-72 hours, 14 days, 30 days, 90 days and 180 days, respectively. There was one patient (9%) with a positive TRUS biopsy at 6 months, which resulted in a retreatment. There were no rectal injuries. Average pre-treatment IPSS, IIEF, and SF-36 scores were 9.55, 16.1, and 103.5. At the 30 day follow-up, they were 18.3, 3, and 97.4, respectively. HIFU is a minimally invasive modality that achieves complete prostatic ablation and is efficacious in the treatment of low-stage prostate cancer.

  7. Comparison of microwave, ultrasound and accelerated-assisted solvent extraction for recovery of polyphenols from Citrus sinensis peels.

    Science.gov (United States)

    Nayak, Balunkeswar; Dahmoune, Farid; Moussi, Kamal; Remini, Hocine; Dairi, Sofiane; Aoun, Omar; Khodir, Madani

    2015-11-15

    Peel of Citrus sinensis contains significant amounts of bioactive polyphenols that could be used as ingredients for a number of value-added products with health benefits. Extraction of polyphenols from the peels was performed using a microwave-assisted extraction (MAE) technique. The effects of aqueous acetone concentration, microwave power, extraction time and solvent-to-solid ratio on the total phenolic content (TPC), total antioxidant activity (TAA) (using DPPH and ORAC-values) and individual phenolic acids (IPA) were investigated using a response surface method. The TPC, TAA and IPA of peel extracts using MAE was compared with conventional, ultrasound-assisted and accelerated solvent extraction. The maximum predicted TPC under the optimal MAE conditions (51% acetone concentration in water (v/v), 500 W microwave power, 122 s extraction time and 25 mL g(-1) solvent to solid ratio), was 12.20 mg GAE g(-1) DW. The TPC and TAA in MAE extracts were higher than the other three extracts.

  8. Ultrasound-Assisted Focused Open Necrosectomy in the Treatment of Necrotizing Pancreatitis

    Directory of Open Access Journals (Sweden)

    Guntars Pupelis

    2015-03-01

    Full Text Available Introduction The surgical treatment of necrotizing pancreatitis includes percutaneous drainage of acute necrotic collections and sequestrectomy in the late phase of the disease. The aim of the study was to compare the conventional open necrosectomy (CON approach with the alternative focused open necrosectomy (FON approach in patients with infected necrosis and progression of sepsis. Methods Patients with acute necrotizing pancreatitis were included in the study prospectively from January 2004 to July 2014. All patients had been admitted with the first or a new episode of disease. Symptomatic large fluid collections were drained percutaneously. The step-up approach was used in patients with several distant localizations of infected necrosis. The methods were analysed by comparing the individual severity according to the ASA, APACHE II and SOFA scores, infection rate, postoperative complication rate and mortality. Results A total of 31 patientswere included in the FON group and 39 in the CON group. The incidence of infection was similar in groups. More ASA III comorbid conditions, a higher APACHE II score, a more frequent need for renal replacement therapy was observed in the CON group. The postoperative complication rate was in the range of 32% to 44%; mortality reached 6.5% in the FON group and 12.8% in the CON group. Conclusions Comorbid conditions, organ failure, and infection are the main risk factors in patients with necrotizing pancreatitis. The step-up approach and perioperative ultrasonography navigation improves the clinical outcome and reduces the extent of invasive surgical intervention in patients unsuited to other minimally invasive procedures.

  9. Modeling localized delivery of Doxorubicin to the brain following focused ultrasound enhanced blood-brain barrier permeability

    International Nuclear Information System (INIS)

    Doxorubicin (Dox) is a well-established chemotherapeutic agent, however it has limited efficacy in treating brain malignancies due to the presence of the blood-brain barrier (BBB). Recent preclinical studies have demonstrated that focused ultrasound induced BBB disruption (BBBD) enables efficient delivery of Dox to the brain. For future treatment planning of BBBD-based drug delivery, it is crucial to establish a mathematical framework to predict the effect of transient BBB permeability enhancement on the spatiotemporal distribution of Dox at the targeted area. The constructed model considers Dox concentrations within three compartments (plasma, extracellular, intracellular) that are governed by various transport processes (e.g. diffusion in interstitial space, exchange across vessel wall, clearance by cerebral spinal fluid, uptake by brain cells). By examining several clinical treatment aspects (e.g. sonication scheme, permeability enhancement, injection mode), our simulation results support the experimental findings of optimal interval delay between two consecutive sonications and therapeutically-sufficient intracellular concentration with respect to transfer constant Ktrans range of 0.01–0.03 min−1. Finally, the model suggests that infusion over a short duration (20–60 min) should be employed along with single-sonication or multiple-sonication at 10 min interval to ensure maximum delivery to the intracellular compartment while attaining minimal cardiotoxicity via suppressing peak plasma concentration. (paper)

  10. Management of Respiratory Motion in Extracorporeal High-Intensity Focused Ultrasound Treatment in Upper Abdominal Organs: Current Status and Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Muller, A., E-mail: arnaud.muller@chu-lyon.fr [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France); Petrusca, L.; Auboiroux, V. [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland); Valette, P. J. [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France); Salomir, R. [University of Geneva, Department of Radiology, Faculty of Medicine (Switzerland); Cotton, F. [Centre Hospitalier Lyon Sud, Service de Radiologie, Hospices Civils de Lyon (France)

    2013-12-15

    Extracorporeal high-intensity focused ultrasound (HIFU) is a minimally invasive therapy considered with increased interest for the ablation of small tumors in deeply located organs while sparing surrounding critical tissues. A multitude of preclinical and clinical studies have showed the feasibility of the method; however, concurrently they showed several obstacles, among which the management of respiratory motion of abdominal organs is at the forefront. The aim of this review is to describe the different methods that have been proposed for managing respiratory motion and to identify their advantages and weaknesses. First, we specify the characteristics of respiratory motion for the liver, kidneys, and pancreas and the problems it causes during HIFU planning, treatment, and monitoring. Second, we make an inventory of the preclinical and clinical approaches used to overcome the problem of organ motion. Third, we analyze their respective benefits and drawbacks to identify the remaining physical, technological, and clinical challenges. We thereby consider the outlook of motion compensation techniques and those that would be the most suitable for clinical use, particularly under magnetic resonance thermometry monitoring.

  11. Focused ultrasound-induced blood-brain barrier opening to enhance temozolomide delivery for glioblastoma treatment: a preclinical study.

    Directory of Open Access Journals (Sweden)

    Kuo-Chen Wei

    Full Text Available The purpose of this study is to assess the preclinical therapeutic efficacy of magnetic resonance imaging (MRI-monitored focused ultrasound (FUS-induced blood-brain barrier (BBB disruption to enhance Temozolomide (TMZ delivery for improving Glioblastoma Multiforme (GBM treatment. MRI-monitored FUS with microbubbles was used to transcranially disrupt the BBB in brains of Fisher rats implanted with 9L glioma cells. FUS-BBB opening was spectrophotometrically determined by leakage of dyes into the brain, and TMZ was quantitated in cerebrospinal fluid (CSF and plasma by LC-MS\\MS. The effects of treatment on tumor progression (by MRI, animal survival and brain tissue histology were investigated. Results demonstrated that FUS-BBB opening increased the local accumulation of dyes in brain parenchyma by 3.8-/2.1-fold in normal/tumor tissues. Compared to TMZ alone, combined FUS treatment increased the TMZ CSF/plasma ratio from 22.7% to 38.6%, reduced the 7-day tumor progression ratio from 24.03 to 5.06, and extended the median survival from 20 to 23 days. In conclusion, this study provided preclinical evidence that FUS BBB-opening increased the local concentration of TMZ to improve the control of tumor progression and animal survival, suggesting its clinical potential for improving current brain tumor treatment.

  12. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis

    Directory of Open Access Journals (Sweden)

    Fouad Aoun

    2015-01-01

    Full Text Available Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon’s rank-sum or χ2 test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p<0.05. Median oncologic follow-up was 83 months (13–123 months in the HIFU cohort and 44 months (13–89 months in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p<0.05. No statistically significant difference in metastasis-free, cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results.

  13. Synergistic ablation of liver tissue and liver cancer cells with high-intensity focused ultrasound and ethanol.

    Science.gov (United States)

    Hoang, Nguyen H; Murad, Hakm Y; Ratnayaka, Sithira H; Chen, Chong; Khismatullin, Damir B

    2014-08-01

    We investigated the combined effect of ethanol and high-intensity focused ultrasound (HIFU), first, on heating and cavitation bubble activity in tissue-mimicking phantoms and porcine liver tissues and, second, on the viability of HepG2 liver cancer cells. Phantoms or porcine tissues were injected with ethanol and then subjected to HIFU at acoustic power ranging from 1.2 to 20.5 W (HIFU levels 1-7). Cavitation events and the temperature around the focal zone were measured with a passive cavitation detector and embedded type K thermocouples, respectively. HepG2 cells were subjected to 4% ethanol solution in growth medium (v/v) just before the cells were exposed to HIFU at 2.7, 8.7 or 12.0 W for 30 s. Cell viability was measured 2, 24 and 72 h post-treatment. The results indicate that ethanol and HIFU have a synergistic effect on liver cancer ablation as manifested by greater temperature rise and lesion volume in liver tissues and reduced viability of liver cancer cells. This effect is likely caused by reduction of the cavitation threshold in the presence of ethanol and the increased rate of ethanol diffusion through the cell membrane caused by HIFU-induced streaming, sonoporation and heating.

  14. The efficacy of high-intensity, focused ultrasound treatment for non-neoplastic epithelial disorders of the vulva.

    Science.gov (United States)

    Zhou, W; Zhu, L; Zhou, H; Shen, K; Lang, J; Cui, Q; Shi, H

    2016-01-01

    Non-neoplastic epithelial disorders of the vulva (NNEDV) are common types of vulval lesions. Although corticosteroids represent a first-line treatment for NNEDV, concerns exist about the safety associated with long-term topical corticosteroid use. Recently, several clinical trials have identified high-intensity focused ultrasound (HIFU) as a promising treatment modality for NNEDV. The aim of this multi-center, randomized, controlled clinical trial was to investigate the efficacy of HIFU therapy in women with NNEDV based on histological alterations. We enrolled patients who were clinically diagnosed with NNEDV. They were randomized into 2 treatment groups: 1) halcinonide for 3 months or 2) HIFU once. A total of 123 patients were biopsied both prior to and after the therapy, and 62 and 61 patients were assigned to the HIFU and halcinonide groups, respectively. The histological changes were then analyzed. After the treatments, the therapeutic effects were observed in both groups. Comparing the diagnosis and alterations in lichenoid and sclerotic patterns and in chronic inflammation, we found statistically significant differences. Furthermore, when compared with the halcinonide group, the HIFU group exhibited enhanced curative effects that were statistically significant (P = 0.039). Based on the histological evidence from this randomized, controlled trial, HIFU represents an effective method for the treatment of NNEDV. PMID:27188744

  15. Effect of low-intensity focused ultrasound on the middle ear in a mouse model of acute otitis media.

    Science.gov (United States)

    Noda, Kanako; Hirano, Takashi; Noda, Kenji; Kodama, Satoru; Ichimiya, Issei; Suzuki, Masashi

    2013-03-01

    We hypothesized that low-intensity focused ultrasound (LIFU) increases vessel permeability and antibacterial drug activity in the mouse middle ear. We determined appropriate settings by applying LIFU to mouse ears with the external auditory canal filled with normal saline and performed histologic and immunohistologic examination. Acute otitis media was induced in mice with nontypable Haemophilus influenzae, and they were given ampicillin (50, 10, or 2 mg/kg) intraperitoneally once daily for 3 days with or without LIFU (1.0 W/cm(2), 20% duty cycle, 30 s). In the LIFU(+) groups receiving the 2- and 10-mg/kg doses, viable bacteria counts, number of inflammatory cells and IL-1β and TNF-α levels in middle ear effusion were significantly lower than in the LIFU(-) groups on the same doses. Severity of AOM also tended to be reduced more in the LIFU(+) groups than in the LIFU(-) groups. LIFU application with antibiotics may be effective for middle ear infection.

  16. Adjuvant hormone therapy in patients undergoing high-intensity focused ultrasound therapy for locally advanced prostate cancer

    Directory of Open Access Journals (Sweden)

    A. I. Neimark

    2014-01-01

    Full Text Available Objective: to evaluate the efficiency and safety of using the luteinizing hormone releasing hormone leuprorelin with the Atrigel delivery system in doses of 7.5, 22.5, and 45 mg as an adjuvant regimen in high- and moderate-risk cancer patients who have received high-intensity focused ultrasound (HIFU therapy.Subjects and methods. Moderate- and high-risk locally advanced prostate cancer (PC patients treated with HIFU (n = 28 and HIFU in combination with hormone therapy during 6 months (n = 31 were examined.Results. The investigation has shown that leuprorelin acetate monotherapy used within 6 months after HIFU therapy can achieve the highest reduction in prostate-specific antigen levels and positively affect the symptoms of the disease. HIFU in combination with androgen deprivation substantially diminishes the clinical manifestations of the disease and improves quality of life in HIFU-treated patients with PC, by reducing the degree of infravesical obstruction (according to uroflowmetric findings and IPSS scores, and causes a decrease in prostate volume as compared to those who have undergone HIFU only. Treatment with leuprorelin having the Atrigel delivery system has demonstrated the low incidence of adverse reactions and good tolerability.

  17. MRI methods for the evaluation of high intensity focused ultrasound tumor treatment: Current status and future needs.

    Science.gov (United States)

    Hectors, Stefanie J C G; Jacobs, Igor; Moonen, Chrit T W; Strijkers, Gustav J; Nicolay, Klaas

    2016-01-01

    Thermal ablation with high intensity focused ultrasound (HIFU) is an emerging noninvasive technique for the treatment of solid tumors. HIFU treatment of malignant tumors requires accurate treatment planning, monitoring and evaluation, which can be facilitated by performing the procedure in an MR-guided HIFU system. The MR-based evaluation of HIFU treatment is most often restricted to contrast-enhanced T1 -weighted imaging, while it has been shown that the non-perfused volume may not reflect the extent of nonviable tumor tissue after HIFU treatment. There are multiple studies in which more advanced MRI methods were assessed for their suitability for the evaluation of HIFU treatment. While several of these methods seem promising regarding their sensitivity to HIFU-induced tissue changes, there is still ample room for improvement of MRI protocols for HIFU treatment evaluation. In this review article, we describe the major acute and delayed effects of HIFU treatment. For each effect, the MRI methods that have been-or could be-used to detect the associated tissue changes are described. In addition, the potential value of multiparametric MRI for the evaluation of HIFU treatment is discussed. The review ends with a discussion on future directions for the MRI-based evaluation of HIFU treatment.

  18. Modeling localized delivery of Doxorubicin to the brain following focused ultrasound enhanced blood-brain barrier permeability

    Science.gov (United States)

    Nhan, Tam; Burgess, Alison; Lilge, Lothar; Hynynen, Kullervo

    2014-10-01

    Doxorubicin (Dox) is a well-established chemotherapeutic agent, however it has limited efficacy in treating brain malignancies due to the presence of the blood-brain barrier (BBB). Recent preclinical studies have demonstrated that focused ultrasound induced BBB disruption (BBBD) enables efficient delivery of Dox to the brain. For future treatment planning of BBBD-based drug delivery, it is crucial to establish a mathematical framework to predict the effect of transient BBB permeability enhancement on the spatiotemporal distribution of Dox at the targeted area. The constructed model considers Dox concentrations within three compartments (plasma, extracellular, intracellular) that are governed by various transport processes (e.g. diffusion in interstitial space, exchange across vessel wall, clearance by cerebral spinal fluid, uptake by brain cells). By examining several clinical treatment aspects (e.g. sonication scheme, permeability enhancement, injection mode), our simulation results support the experimental findings of optimal interval delay between two consecutive sonications and therapeutically-sufficient intracellular concentration with respect to transfer constant Ktrans range of 0.01-0.03 min-1. Finally, the model suggests that infusion over a short duration (20-60 min) should be employed along with single-sonication or multiple-sonication at 10 min interval to ensure maximum delivery to the intracellular compartment while attaining minimal cardiotoxicity via suppressing peak plasma concentration.

  19. 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.)

  20. Cavitation-induced damage of soft materials by focused ultrasound bursts: A fracture-based bubble dynamics model.

    Science.gov (United States)

    Movahed, Pooya; Kreider, Wayne; Maxwell, Adam D; Hutchens, Shelby B; Freund, Jonathan B

    2016-08-01

    A generalized Rayleigh-Plesset-type bubble dynamics model with a damage mechanism is developed for cavitation and damage of soft materials by focused ultrasound bursts. This study is linked to recent experimental observations in tissue-mimicking polyacrylamide and agar gel phantoms subjected to bursts of a kind being considered specifically for lithotripsy. These show bubble activation at multiple sites during the initial pulses. More cavities appear continuously through the course of the observations, similar to what is deduced in pig kidney tissues in shock-wave lithotripsy. Two different material models are used to represent the distinct properties of the two gel materials. The polyacrylamide gel is represented with a neo-Hookean elastic model and damaged based upon a maximum-strain criterion; the agar gel is represented with a strain-hardening Fung model and damaged according to the strain-energy-based Griffith's fracture criterion. Estimates based upon independently determined elasticity and viscosity of the two gel materials suggest that bubble confinement should be sufficient to prevent damage in the gels, and presumably injury in some tissues. Damage accumulation is therefore proposed to occur via a material fatigue, which is shown to be consistent with observed delays in widespread cavitation activity. PMID:27586763

  1. Wavelet-transform-based active imaging of cavitation bubbles in tissues induced by high intensity focused ultrasound.

    Science.gov (United States)

    Liu, Runna; Xu, Shanshan; Hu, Hong; Huo, Rui; Wang, Supin; Wan, Mingxi

    2016-08-01

    Cavitation detection and imaging are essential for monitoring high-intensity focused ultrasound (HIFU) therapies. In this paper, an active cavitation imaging method based on wavelet transform is proposed to enhance the contrast between the cavitation bubbles and surrounding tissues. The Yang-Church model, which is a combination of the Keller-Miksis equation with the Kelvin-Voigt equation for the pulsations of gas bubbles in simple linear viscoelastic solids, is utilized to construct the bubble wavelet. Experiments with porcine muscles demonstrate that image quality is associated with the initial radius of the bubble wavelet and the scale. Moreover, the Yang-Church model achieves a somewhat better performance compared with the Rayleigh-Plesset-Noltingk-Neppiras-Poritsky model. Furthermore, the pulse inversion (PI) technique is combined with bubble wavelet transform to achieve further improvement. The cavitation-to-tissue ratio (CTR) of the best tissue bubble wavelet transform (TBWT) mode image is improved by 5.1 dB compared with that of the B-mode image, while the CTR of the best PI-based TBWT mode image is improved by 7.9 dB compared with that of the PI-based B-mode image. This work will be useful for better monitoring of cavitation in HIFU-induced therapies. PMID:27586712

  2. Role of Focal Therapy with High-Intensity Focused Ultrasound in the Management of Clinically Localized Prostate Cancer.

    Science.gov (United States)

    Kuru, Timur H; van Essen, Julius; Pfister, David; Porres, Daniel

    2015-01-01

    Overtreatment of prostate cancer (PC) remains one of the main burdens in uro-oncology. Focal therapy may be a reasonable alternative with less side effects and morbidity. Application of high-intensity focused ultrasound (HIFU) induces immediate and irreversible coagulation. The treatment leads to consecutive necrosis with sharply delineated margins, making HIFU a promising tool for the focal therapy of localized PC. Unlike radiation, the treatment leaves no collateral damage outside of the heated tissue, allowing repeated use of HIFU, if necessary. In case of non-organ-confined relapse, additional radical salvage therapy can be performed. This review gives an overview of the existing evidence on focal HIFU. Today, 3 HIFU devices are approved for the treatment of localized PC: Sonablate™, Ablatherm™ and the FocalOne™ device. In summary, the first published results of focal HIFU are promising. The quality of life and potency of the patients are well preserved. Therefore, HIFU treatment, and especially focal ablation of tumor foci, seems to be a safe alternative to standard treatment, with low side effects. The oncologic results seem satisfactory but need further follow-up to validate this practice of PC control. PMID:26632846

  3. High Intensity Focused Ultrasound versus Brachytherapy for the Treatment of Localized Prostate Cancer: A Matched-Pair Analysis.

    Science.gov (United States)

    Aoun, Fouad; Limani, Ksenija; Peltier, Alexandre; Marcelis, Quentin; Zanaty, Marc; Chamoun, Alexandre; Vanden Bossche, Marc; Roumeguère, Thierry; van Velthoven, Roland

    2015-01-01

    Purpose. To evaluate postoperative morbidity and long term oncologic and functional outcomes of high intensity focused ultrasound (HIFU) compared to brachytherapy for the treatment of localized prostate cancer. Material and Methods. Patients treated by brachytherapy were matched 1 : 1 with patients who underwent HIFU. Differences in postoperative complications across the two groups were assessed using Wilcoxon's rank-sum or χ (2) test. Kaplan-Meier curves, log-rank tests, and Cox regression models were constructed to assess differences in survival rates between the two groups. Results. Brachytherapy was significantly associated with lower voiding LUTS and less frequent acute urinary retention (p HIFU cohort and 44 months (13-89 months) in the brachytherapy cohort. Median time to achieve PSA nadir was statistically shorter in the HIFU. Biochemical recurrence-free survival rate was significantly higher in the brachytherapy cohort compared to HIFU cohort (68.5% versus 53%, p cancer specific, and overall survivals was observed between the two groups. Conclusion. HIFU and brachytherapy are safe with no significant difference in cancer specific survival on long term oncologic follow-up. Nonetheless, a randomized controlled trial is needed to confirm these results. PMID:26357511

  4. Adjuvant hormone therapy in patients undergoing high-intensity focused ultrasound therapy for locally advanced prostate cancer

    Directory of Open Access Journals (Sweden)

    A. I. Neimark

    2014-11-01

    Full Text Available Objective: to evaluate the efficiency and safety of using the luteinizing hormone releasing hormone leuprorelin with the Atrigel delivery system in doses of 7.5, 22.5, and 45 mg as an adjuvant regimen in high- and moderate-risk cancer patients who have received high-intensity focused ultrasound (HIFU therapy.Subjects and methods. Moderate- and high-risk locally advanced prostate cancer (PC patients treated with HIFU (n = 28 and HIFU in combination with hormone therapy during 6 months (n = 31 were examined.Results. The investigation has shown that leuprorelin acetate monotherapy used within 6 months after HIFU therapy can achieve the highest reduction in prostate-specific antigen levels and positively affect the symptoms of the disease. HIFU in combination with androgen deprivation substantially diminishes the clinical manifestations of the disease and improves quality of life in HIFU-treated patients with PC, by reducing the degree of infravesical obstruction (according to uroflowmetric findings and IPSS scores, and causes a decrease in prostate volume as compared to those who have undergone HIFU only. Treatment with leuprorelin having the Atrigel delivery system has demonstrated the low incidence of adverse reactions and good tolerability.

  5. High-Intensity Focused Ultrasound (HIFU) Using Sonablate-500 for the Treatment of Localized Prostate Cancer: 6-year experience

    Science.gov (United States)

    Uchida, Toyoaki; Shoji, Sunao; Nagata, Yoshihiro

    2006-05-01

    We evaluated 281 patients of localized prostate cancer treated with high-intensity focused ultrasound (HIFU) for biochemical disease-free rate, safety, morbidity and predictors of biochemical outcome. A total of 281 patients underwent HIFU with the use of Sonablate-500 and with at least 12 months of follow-up. Biochemical failure was defined according to the criteria recommended by the American Society for Therapeutic Radiology and Oncology Consensus Panel. The biochemical disease-free rates at 1, 3 and 5 years in all patients were 78%, 74% and 72%, respectively. The biochemical disease-free rates at 5 years for patients with pretreatment PSA less than 10 ng/ml, 10.01 to 20.0 ng/ml and more than 20.0 ng/ml were 88%, 70% and 17%, respectively (pHIFU therapy appears to be a safe and efficacious minimally invasive therapy for patients with localized prostate cancer, especially those with a pretreatment PSA level less than 20 ng/ml.

  6. High-Intensity Focused Ultrasound in the Treatment of Hepatic Metastases from Colorectal Cancer of 18 Patients

    Institute of Scientific and Technical Information of China (English)

    HuiZhu; WenzhiChen; FengWu; KequanLi; JianzhongZou; ZhibiaoWang

    2004-01-01

    OBJECTIVE To evaluate the safety and effectiveness of treatment of hepatic metastases from colorectal cancer using high-intensity focused ultrasound (HIFU). METHODS Thirty-one lesions in 18 patients with hepatic metastases from colorectal cancer after colectomy were treated with HIFU therapy. The vital signs, function of the vital organs, complications and pathological outcome were studied using imaging examinations such as CT or MRI. RESULTS The vital signs of all patients remained stable and their liver and kidney functions normal. Two of the 18 patients were not followed-up. After a mean follow-up of 16.1 months (6-38 months), 13 survived. The survival rates at the 12th and 18th months were 83.3% and 66.7%, respectively. The median survival rate was 16 months. Among the 25 lesions followed-up, 17 shrank over 50%, 5 grew new metastases and superficial degree II skin injury occurred in 8. CONCLUSION HIFU is a safe, effective and non-invasive option for the treatment of hepatic metastases from colorectal cancer.

  7. Transarterial infusion chemotherapy combined with high intensity focused ultrasound for the treatment of pancreatic carcinomas: a clinical study

    International Nuclear Information System (INIS)

    Objective: To assess the clinical value of transarterial infusion chemotherapy combined with high intensity focused ultrasound (HIFU) for the treatment of pancreatic carcinomas. Methods: A total of 64 patients with inoperable pancreatic carcinomas were randomly divided into study group (n=32) and control group (n=32). Transarterial infusion chemotherapy combined with HIFU was employed in patients of study group, while simple transarterial infusion chemotherapy was conducted in patients of control group. The effective rate, the clinical benefit rate (CBR), the occurrence of side effect and the survival time of the two groups were recorded. The results were compared between the two groups. Results: The effective rate (PR + MR), the median survival time and the one-year survival rate of the study group were 55.56%, 13.0 months and 68.75% respectively, while the effective rate (PR + MR), the median survival time and the one-year survival rate of the control group were 28.57%, 9.0 months and 43.75% respectively. Both the effective rate and the one-year survival rate of the study group were significantly higher than those of the control group (P<0.05). Conclusion: Compared with pure transarterial infusion chemotherapy, transarterial infusion chemotherapy combined with HIFU can significantly improve the short-term efficacy and increase the one-year survival rate for patients with advanced pancreatic carcinomas. (authors)

  8. Cavitation-induced damage of soft materials by focused ultrasound bursts: A fracture-based bubble dynamics model.

    Science.gov (United States)

    Movahed, Pooya; Kreider, Wayne; Maxwell, Adam D; Hutchens, Shelby B; Freund, Jonathan B

    2016-08-01

    A generalized Rayleigh-Plesset-type bubble dynamics model with a damage mechanism is developed for cavitation and damage of soft materials by focused ultrasound bursts. This study is linked to recent experimental observations in tissue-mimicking polyacrylamide and agar gel phantoms subjected to bursts of a kind being considered specifically for lithotripsy. These show bubble activation at multiple sites during the initial pulses. More cavities appear continuously through the course of the observations, similar to what is deduced in pig kidney tissues in shock-wave lithotripsy. Two different material models are used to represent the distinct properties of the two gel materials. The polyacrylamide gel is represented with a neo-Hookean elastic model and damaged based upon a maximum-strain criterion; the agar gel is represented with a strain-hardening Fung model and damaged according to the strain-energy-based Griffith's fracture criterion. Estimates based upon independently determined elasticity and viscosity of the two gel materials suggest that bubble confinement should be sufficient to prevent damage in the gels, and presumably injury in some tissues. Damage accumulation is therefore proposed to occur via a material fatigue, which is shown to be consistent with observed delays in widespread cavitation activity.

  9. Single High Intensity Focused Ultrasound Session as a Whole Gland Primary Treatment for Clinically Localized Prostate Cancer: 10-Year Outcomes

    Directory of Open Access Journals (Sweden)

    Ksenija Limani

    2014-01-01

    Full Text Available Objectives. To assess the treatment outcomes of a single session of whole gland high intensity focused ultrasound (HIFU for patients with localized prostate cancer (PCa. Methods. Response rates were defined using the Stuttgart and Phoenix criteria. Complications were graded according to the Clavien score. Results. At a median follow-up of 94months, 48 (44.4% and 50 (46.3% patients experienced biochemical recurrence for Phoenix and Stuttgart definition, respectively. The 5- and 10-year actuarial biochemical recurrence free survival rates were 57% and 40%, respectively. The 10-year overall survival rate, cancer specific survival rate, and metastasis free survival rate were 72%, 90%, and 70%, respectively. Preoperative high risk category, Gleason score, preoperative PSA, and postoperative nadir PSA were independent predictors of oncological failure. 24.5% of patients had self-resolving LUTS, 18.2% had urinary tract infection, and 18.2% had acute urinary retention. A grade 3b complication occurred in 27 patients. Pad-free continence rate was 87.9% and the erectile dysfunction rate was 30.8%. Conclusion. Single session HIFU can be alternative therapy for patients with low risk PCa. Patients with intermediate risk should be informed about the need of multiple sessions of HIFU and/or adjuvant treatments and HIFU performed very poorly in high risk patients.

  10. High intensity focused ultrasound (HIFU) therapy for local treatment of hepatocellular carcinoma: Role of partial rib resection

    International Nuclear Information System (INIS)

    Objective: It has long been known that high intensity focused ultrasound (HIFU) can kill tissue through coagulative necrosis. However, it is only in recent years that practical clinical applications are becoming possible. Since the ribs have strong reflections to ultrasonic beams, they may affect the deposition of ultrasound energy, decreasing the efficacy of HIFU treatment and increasing the chance of adverse events when the intra-abdominal tumours concealed by ribs are treated. The aim of this study was to evaluate the influence of partial rib resection on the efficacy and safety of HIFU treatment. Methods: This prospective study was approved by the ethics committee at Chongqing University of Medical Sciences. An informed consent form was obtained from each patient and family member. A total of 16 patients with hepatocellular carcinoma (HCC), consisting of 13 males and 3 females, were studied. All patients had the successful HIFU treatment. To create a better acoustic pathway for HIFU treatment, all of the 16 patients had the ribs that shield the tumour mass to be removed. Magnetic resonance imaging (MRI) was used to evaluate the efficacy of HIFU treatment. Results: Sixteen cases had 23 nodules, including 12 cases with a single nodule, 1 case with 2 nodules, 3 cases with 3 nodules. The mean diameter of tumours was 7.0 ± 2.1 cm (5-10 cm). According to TNM classification, 9 patients were diagnosed as stage II, 4 patients were stage III, and 3 patients were stage IV. Follow-up imaging showed an absence of tumour blood supply and shrinkage of all treated lesions. The survival rates at 1, 2, 3, 4, and 5 years were 100%, 83.3%, 69.4%, 55.6%, and 55.6%, respectively. No serious complications were observed in the patients treated with HIFU. Conclusion: Partial rib resection can create a better acoustic pathway of HIFU therapy. Even though it is an invasive treatment, this measure offers patients an improved prospect of complete tumour ablation when no other treatment is

  11. Effect of hydrodynamic cavitation in the tissue erosion by pulsed high-intensity focused ultrasound (pHIFU)

    Science.gov (United States)

    Zhou, Yufeng; Gao, Xiaobin Wilson

    2016-09-01

    High-intensity focused ultrasound (HIFU) is emerging as an effective therapeutic modality in clinics. Besides the thermal ablation, tissue disintegration is also possible because of the interaction between the distorted HIFU bursts and either bubble cloud or boiling bubble. Hydrodynamic cavitation is another type of cavitation and has been employed widely in industry, but its role in mechanical erosion to tissue is not clearly known. In this study, the bubble dynamics immediately after the termination of HIFU exposure in the transparent gel phantom was captured by high-speed photography, from which the bubble displacement towards the transducer and the changes of bubble size was quantitatively determined. The characteristics of hydrodynamic cavitation due to the release of the acoustic radiation force and relaxation of compressed surrounding medium were found to associate with the number of pulses delivered and HIFU parameters (i.e. pulse duration and pulse repetition frequency). Because of the initial big bubble (~1 mm), large bubble expansion (up to 1.76 folds), and quick bubble motion (up to ~1 m s-1) hydrodynamic cavitation is significant after HIFU exposure and may lead to mechanical erosion. The shielding effect of residual tiny bubbles would reduce the acoustic energy delivered to the pre-existing bubble at the focus and, subsequently, the hydrodynamic cavitation effect. Tadpole shape of mechanical erosion in ex vivo porcine kidney samples was similar to the contour of bubble dynamics in the gel. Liquefied tissue was observed to emit towards the transducer through the punctured tissue after HIFU exposure in the sonography. In summary, the release of HIFU exposure-induced hydrodynamic cavitation produces significant bubble expansion and motion, which may be another important mechanism of tissue erosion. Understanding its mechanism and optimizing the outcome would broaden and enhance HIFU applications.

  12. Prospects for an Accelerator Program in Mexico Focused on Photon Science

    Energy Technology Data Exchange (ETDEWEB)

    Carlos Hernandez-Garcia, Mauro Napsuciale

    2011-05-01

    Recent interest in developing an accelerator-based light source in Mexico has driven several actions by the Division of Particles and Fields in Mexico, and by the electron accelerator community in the United States. We report on activities over the past two years that are very encouraging and offer a variety of possibilities to start the development of an accelerator program in Mexico. A suggested path towards this goal that would eventually lead to building, commissioning and operating a third or fourth generation light source will also be presented

  13. Prospects for an Accelerator Program in Mexico Focused on Photon Science

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Garcia, C [Jefferson Lab, 12000 Jefferson Ave, Suite 19, Newport News, VA 23606 (United States); Napsuciale, M, E-mail: chgarcia@jlab.org [Departamento de Fisica, Universidad de Guanajuato Campus Leon, Lomas del Bosque 103, Fraccionamiento Lomas del Campestre, 37150, Leon, Guanajuato (Mexico)

    2011-04-01

    Recent interest in developing Mexican expertise in Accelerator Science and Technology has resulted in several actions by the Division of Particles and Fields in Mexico, and by the electron accelerator community in the United States. We report on the very encouraging activities over the past two years which were aimed at developing a light source as the most effective starting point. We present a number of possibilities to initiate and grow an accelerator science program and present a path that would lead to building, commissioning and operating a third or fourth generation light source in Mexico.

  14. Ultrasound and Therapy

    Science.gov (United States)

    Lafon, Cyril

    This paper begins with an overview and a description of the interactions between ultrasound and biological tissues encountered during treatment protocols. In a second part of this seminar, two clinical applications of therapeutic ultrasound will be described in details: -Kidney stone destruction by ultrasound (lithotripsy) and High Intensity Focused Ultrasound for treating prostate cancer (HIFU).

  15. Concurrent Chemotherapy and Pulsed High-Intensity Focused Ultrasound Therapy for the Treatment of Unresectable Pancreatic Cancer: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Young; Choi, Byung Ihn; Ryu, Ji Kon; Kim, Yong Tae; Kim, Se Hyung; Han, Joon Koo [Seoul National University Hospital, Seoul (Korea, Republic of); Hwang, Joo Ha [University of Washington Medical Center, Seattle (United States)

    2011-04-15

    This study was performed to evaluate the potential clinical value of concurrent chemotherapy and pulsed high intensity focused ultrasound (HIFU) therapy (CCHT), as well as the safety of pulsed HIFU, for the treatment of unresectable pancreatic cancer. Twelve patients were treated with HIFU from October 2008 to May 2010, and three of them underwent CCHT as the main treatment (the CCHT group). The overall survival (OS), the time to tumor progression (TTP), the complications and the current performance status in the CCHT and non-CCHT groups were analyzed. Nine patients in the non-CCHT group were evaluated to determine why CCHT could not be performed more than twice. The OS of the three patients in the CCHT group was 26.0, 21.6 and 10.8 months, respectively, from the time of diagnosis. Two of them were alive at the time of preparing this manuscript with an excellent performance status, and one of them underwent a surgical resection one year after the initiation of CCHT. The TTP of the three patients in the CCHT group was 13.4, 11.5 and 9.9 months, respectively. The median OS and TTP of the non-CCHT group were 10.3 months and 4.4 months, respectively. The main reasons why the nine patients of the non-CCHT group failed to undergo CCHT more than twice were as follows: pancreatitis (n = 1), intolerance of the pain during treatment (n = 4), palliative use of HIFU for pain relief (n = 1) and a poor physical condition due to disease progression (n = 3). No major complications were encountered except one case of pancreatitis. This study shows that CCHT is a potentially effective and safe modality for the treatment of unresectable pancreatic cancer

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

    International Nuclear Information System (INIS)

    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

  17. Twelve years' experience with high-intensity focused ultrasound (HIFU) using sonablate™ devices for the treatment of localized prostate cancer

    Science.gov (United States)

    Uchida, Toyoaki; Nakano, Muyura; Shoji, Sunao; Nagata, Yoshihiro; Usui, Yukio; Terachi, Toshiro

    2012-10-01

    To report on the long-term results of high-intensity focused ultrasound (HIFU) in the treatment of localized prostate cancer. Patients with clinical Stage T1c-T3N0M0, biopsy proven, localized prostate cancer, with a serum prostate specific antigen (PSA) level of HIFU using the Sonablate™ (S) device and were required to have a minimal follow-up of 2 years after the last HIFU session to be included in this analysis. Four different generation HIFU devices, S200, S500, S500 version 4 and S500 TCM, have been used for this study. Biochemical failure was defined according to the Phoenix definition (PSA nadir+2ng/ml). Seven hundred and fifty-three men with prostate cancer were included. The patients were divided into two groups: in the Former group, 421 patients were treated with S200 and 500 from 1990 to 2005; in the Latter group, 332 patients were treated with S500 ver. 4 and TCM from 2005 to 2009. The mean age, PSA, Gleason score, operation time, and follow-up period in the Former and Latter groups were 68 and 67 years, 11.3 and 9.7 ng/ml, 6.2 and 6.6, 167 and 101 min, and 49 and 38 months, respectively. The biochemical disease-free rate (BDFR) in the groups at 5 years was, respectively, 67% and 53%, and was 50% at 10 years in the Former group (pprostate biopsy rate in the Former and Latter groups was 81% and 93%, respectively. Postoperative erectile dysfunction was noted in 45%, 38%, and 24% of patients at 6 months, 12 months, and 2 years after HIFU. The results after long-term follow-up have indicated that HIFU is an efficient and safe treatment for patients with localized prostate cancer, especially low-and intermediate-risk patients.

  18. Postoperative monitoring of prostate-specific antigen (PSA after treatment with high-intensive focused ultrasound (HIFU

    Directory of Open Access Journals (Sweden)

    Blyumberg B.I.

    2012-12-01

    Full Text Available Research objective: to estimate efficiency of treatment of prostate cancer using high-intensive focused ultrasound on the basis of laboratory analysis of postoperative level prostate-specific antigen (PSA. Objects of research. Objects of research consisted of 110 patients treated in urological clinic of Hospital n.a. S. R. Mirotvortsev (Saratov State Medical University during the period February, 2009 — March, 2012. Patients took 110 sessions of primary operative treatment of prostate cancer by HIFU therapy method. Technique and research methods. Concentration of PSA in blood changed in all patients every 1,5 month within 6 months after operation, irrespective of its kind (including after repeated HIFU, further — after every 3 month till one year, and later on after 6 months. We were guided by references of the International Consensus, which considers PSA level more than 0,5 ng/ml in blood after 3 months of treatment to be unsatisfactory result. We also headed for PSA level before treatment and oncological risk degree. Results. Median nadir formed 0,5 ng/ml PSA by 3 months after treatment. Patients demonstrated different indicators of PSA dynamics depending on oncological risk, stage and hormonal therapy management. Patients with low oncological risk had initially lower PSA concentration, further PSA concentration reached nadir level faster. At patients with widespread forms of prostate cancer accurate dependence of PSA concentration according to prevalence of process was traced. Time of PSA nadir amount did not differ and was marked as 12-14 weeks on average. At patients received hormonal therapy, lower value of PSA nadir was marked. The conclusion. Monitoring of PSA concentration (PSA nadir by 3 months, dynamics of PSA concentration change is of great importance in early revealing of relapse after prostate HIFU therapy. High level of PSA nadir and PSA growth according to time period are important prognostic factors.

  19. Locally recurrent prostate cancer after initial radiation therapy: Early salvage high-intensity focused ultrasound improves oncologic outcomes

    International Nuclear Information System (INIS)

    Purpose: To evaluate pre-operative prognostic risk factors to predict oncologic outcome of Salvage High-Intensity Focused Ultrasound (S-HIFU) for radiorecurrent prostate cancer (PCa). Methods and materials: A total of 290 men with biopsy-confirmed locally radiorecurrent PCa, underwent S-HIFU. D’Amico risk group before external beam radiotherapy (EBRT), Prostate Specific Antigen (PSA), estimated Gleason score prior HIFU and post HIFU biopsies were analyzed for predictive utility of local cancer control, cancer-specific, metastasis free, and progression free survival rates (PFSR). Results: Local cancer control with negative biopsy results was obtained in 81% of the 208 patients who underwent post-S-HIFU biopsies. Median PSA nadir was 0.14 ng/ml and 127 patients did not require androgen deprivation therapy (ADT). The mean follow up was 48 months for cancer-specific survival rates. The cancer-specific and metastasis-free survival rates at 7 years were 80% and 79.6% respectively. The PFSR was significantly influenced by: the pre-HIFU PSA level (hazard ratio (HR): 1.09, 95% CI 1.04–1.13), a Gleason score ⩾8 versus ⩽6 (HR: 1.17, 95% CI 1.03–1.3), and a previous ADT (HR: 1.28, 95% CI 1.09–1.46). The rates of recto-urethral fistula (0.4%) and grade II/III incontinence (19.5%) indicate significant reduction in serious side effects with use of dedicated post-radiation acoustic parameters compared with standard parameters. Conclusion: S-HIFU is an effective curative option for radiorecurrent PCa with acceptable morbidity for localized radiorecurrent PCa, but should be initiated early following EBRT failure. Use of prognostic risk factors can optimize patient selection.

  20. Short-time focused ultrasound hyperthermia enhances liposomal doxorubicin delivery and antitumor efficacy for brain metastasis of breast cancer.

    Science.gov (United States)

    Wu, Sheng-Kai; Chiang, Chi-Feng; Hsu, Yu-Hone; Lin, Tzu-Hung; Liou, Houng-Chi; Fu, Wen-Mei; Lin, Win-Li

    2014-01-01

    The blood-brain/tumor barrier inhibits the uptake and accumulation of chemotherapeutic drugs. Hyperthermia can enhance the delivery of chemotherapeutic agent into tumors. In this study, we investigated the effects of short-time focused ultrasound (FUS) hyperthermia on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer 4T1-luc2 cells expressing firefly luciferase were injected into female BALB/c mice striatum tissues and used as a brain metastasis model. The mice were intravenously injected with PLD (5 mg/kg) with/without 10-minute transcranial FUS hyperthermia on day 6 after tumor implantation. The amounts of doxorubicin accumulated in the normal brain tissues and tumor tissues with/without FUS hyperthermia were measured using fluorometry. The tumor growth for the control, hyperthermia, PLD, and PLD + hyperthermia groups was measured using an IVIS spectrum system every other day from day 3 to day 11. Cell apoptosis and tumor characteristics were assessed using immunohistochemistry. Short-time FUS hyperthermia was able to significantly enhance the PLD delivery into brain tumors. The tumor growth was effectively inhibited by a single treatment of PLD + hyperthermia compared with both PLD alone and short-time FUS hyperthermia alone. Immunohistochemical examination further demonstrated the therapeutic efficacy of PLD plus short-time FUS hyperthermia for brain metastasis of breast cancer. The application of short-time FUS hyperthermia after nanodrug injection may be an effective approach to enhance nanodrug delivery and improve the treatment of metastatic cancers. PMID:25278753

  1. Short-time focused ultrasound hyperthermia enhances liposomal doxorubicin delivery and antitumor efficacy for brain metastasis of breast cancer

    Science.gov (United States)

    Wu, Sheng-Kai; Chiang, Chi-Feng; Hsu, Yu-Hone; Lin, Tzu-Hung; Liou, Houng-Chi; Fu, Wen-Mei; Lin, Win-Li

    2014-01-01

    The blood–brain/tumor barrier inhibits the uptake and accumulation of chemotherapeutic drugs. Hyperthermia can enhance the delivery of chemotherapeutic agent into tumors. In this study, we investigated the effects of short-time focused ultrasound (FUS) hyperthermia on the delivery and therapeutic efficacy of pegylated liposomal doxorubicin (PLD) for brain metastasis of breast cancer. Murine breast cancer 4T1-luc2 cells expressing firefly luciferase were injected into female BALB/c mice striatum tissues and used as a brain metastasis model. The mice were intravenously injected with PLD (5 mg/kg) with/without 10-minute transcranial FUS hyperthermia on day 6 after tumor implantation. The amounts of doxorubicin accumulated in the normal brain tissues and tumor tissues with/without FUS hyperthermia were measured using fluorometry. The tumor growth for the control, hyperthermia, PLD, and PLD + hyperthermia groups was measured using an IVIS spectrum system every other day from day 3 to day 11. Cell apoptosis and tumor characteristics were assessed using immunohistochemistry. Short-time FUS hyperthermia was able to significantly enhance the PLD delivery into brain tumors. The tumor growth was effectively inhibited by a single treatment of PLD + hyperthermia compared with both PLD alone and short-time FUS hyperthermia alone. Immunohistochemical examination further demonstrated the therapeutic efficacy of PLD plus short-time FUS hyperthermia for brain metastasis of breast cancer. The application of short-time FUS hyperthermia after nanodrug injection may be an effective approach to enhance nanodrug delivery and improve the treatment of metastatic cancers. PMID:25278753

  2. Real-time monitoring of high-intensity focused ultrasound treatment using axial strain and axial-shear strain elastograms.

    Science.gov (United States)

    Xia, Rongmin; Thittai, Arun K

    2014-03-01

    Axial strain elastograms (ASEs) have been found to help visualize sonographically invisible thermal lesions. However, in most studies involving high-intensity focused ultrasound (HIFU)-induced thermal lesions, elastography imaging was performed separately later, after the lesion was formed. In this article, the feasibility of monitoring, in real time, tissue elasticity variation during HIFU treatment and immediately thereafter is explored using quasi-static elastography. Further, in addition to ASEs, we also explore the use of simultaneously acquired axial-shear strain elastograms (ASSEs) for HIFU lesion visualization. Experiments were performed on commercial porcine liver samples in vitro. The HIFU experiments were conducted at two applied acoustic power settings, 35 and 20 W. The experimental setup allowed us to interrupt the HIFU pulse momentarily several different times during treatment to perform elastographic compression and data acquisition. At the end of the experiments, the samples were cut along the imaging plane and photographed to compare size and location of the formed lesion with those visualized on ASEs and ASSEs. Single-lesion and multiple-lesion experiments were performed to assess the contribution of ASEs and ASSEs to lesion visualization and treatment monitoring tasks. At both power settings, ASEs and ASSEs provided accurate location information during HIFU treatment. At the low-power setting case, ASEs and ASSEs provide accurate lesion size in real-time monitoring. Lesion appearance in ASEs and ASSEs was affected by the cavitation bubbles produced at the high-power setting. The results further indicate that the cavitation bubbles influence lesion appearance more in ASEs than in ASSEs. Both ASEs and ASSEs provided accurate size information after a waiting period that allowed the cavitation bubbles to disappear. The results indicate that ASSEs not only improve lesion visualization and size measurement of a single lesion, but, under certain

  3. 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.

  4. 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.

  5. Accelerator

    International Nuclear Information System (INIS)

    The invention claims equipment for stabilizing the position of the front covers of the accelerator chamber in cyclic accelerators which significantly increases accelerator reliability. For stabilizing, it uses hydraulic cushions placed between the electromagnet pole pieces and the front chamber covers. The top and the bottom cushions are hydraulically connected. The cushions are disconnected and removed from the hydraulic line using valves. (J.P.)

  6. MRI monitoring of lesions created at temperature below the boiling point and of lesions created above the boiling point using high intensity focused ultrasound

    OpenAIRE

    Damianou, C.; Ioannides, K.; Hadjisavvas, V.; Mylonas, N.; Couppis, A.; Iosif, D.; Kyriacou, P. A.

    2010-01-01

    Magnetic Resonance Imaging (MRI) was utilized to monitor lesions created at temperature below the boiling point and lesions created at temperature above the boiling point using High Intensity Focused Ultrasound (HIFU) in freshly excised kidney, liver and brain and in vivo rabbit kidney and brain. T2-weighted fast spin echo (FSE) was proven as an excellent MRI sequence that can detect lesions with temperature above the boiling point in kidney. This advantage is attributed to the significant di...

  7. Magnetic Resonance Imaging-Guided High-Intensity Focused Ultrasound Ablation of Uterine Fibroids: Effect of Bowel Interposition on Procedure Feasibility and a Unique Bowel Displacement Technique

    OpenAIRE

    Young-Sun Kim; Hyo Keun Lim; Hyunchul Rhim

    2016-01-01

    Purpose To evaluate the effect of bowel interposition on assessing procedure feasibility, and the usefulness and limiting conditions of bowel displacement techniques in magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) ablation of uterine fibroids. Materials and Methods Institutional review board approved this study. A total of 375 screening MR exams and 206 MR-HIFU ablations for symptomatic uterine fibroids performed between August 2010 and March 2015 were retrosp...

  8. Single application of high-intensity focused ultrasound as primary therapy of localized prostate cancer: Treatment-related predictors of biochemical outcomes

    OpenAIRE

    Dietrich Pfeiffer; Juergen Berger; Andreas Gross

    2015-01-01

    Objective: Recent reports on high-intensity focused ultrasound (HIFU) treatment of localized prostate cancer suggest that preoperative risk groups of tumor recurrence are strong predictors of oncological outcomes. The purpose of this study is to determine the prognostic significance of treatment-related factors in relation to patient characteristics for biochemical outcomes after HIFU. Methods: This retrospective single-center study included patients treated from December 2002 to December ...

  9. A multi-centre prospective development study evaluating focal therapy using high intensity focused ultrasound for localised prostate cancer: The INDEX study.

    OpenAIRE

    Dickinson, L.; Ahmed, H. U.; Kirkham, A; Allen, C.; Freeman, A; Barber, J; Hindley, R; Leslie, T.; Ogden, C.; Persad, R; Winkler, M.H.; Emberton, M; on behalf of the INDEX Study Group

    2013-01-01

    Introduction Focal therapy offers the possibility of cancer control, without the side effect profile of radical therapies. Early single centre prospective development studies using high intensity focused ultrasound (HIFU) have demonstrated encouraging genitourinary functional preservation and short-term cancer control. Large multi-centre trials are required to evaluate medium-term cancer control and reproduce functional recovery. We describe the study design of an investigator-led UK multi-ce...

  10. Non-invasive magnetic resonance-guided high intensity focused ultrasound ablation of a vascular malformation in the lower extremity : a case report

    OpenAIRE

    van Breugel, Marjolein; Nijenhuis, Robbert J; Ries, Mario G.; Toorop, RJ; Vonken, EPA; Wijlemans, JW; van den Bosch, Maurice A. A. J.

    2015-01-01

    INTRODUCTION: Therapy of choice for symptomatic vascular malformations consists of surgery, sclerotherapy, or embolization. However, these techniques are invasive with possible complications and require hospitalization. We present a novel non-invasive technique, i.e., magnetic resonance-guided high-intensity focused ultrasound (MR-HIFU) ablation, for the treatment of a vascular malformation in a patient. This technique applies high-intensity sound waves transcutaneously to the body and is ful...

  11. Comparison of Transrectal Prostate Biopsy Results with Histology of Transurethral Resection of the Prostate in Men Undergoing High-Intensity Focused Ultrasound

    OpenAIRE

    Rogenhofer, Sebastian; Walter, Bernhard; Hartmann, Arndt; Wieland, Walter Ferdinand; Mueller, S.C.; Blana, Andreas

    2014-01-01

    Introduction: The aim of our study was to evaluate the significance of transurethral resection of the prostate (TURP) to detect prostate cancer (PCa). A comparison was performed of the TURP specimens of patients undergoing high-intensity focused ultrasound (HIFU) with the core biopsies. Materials and Methods: TURP before undergoing HIFU therapy was performed in 106 patients without neoadjuvant treatment. The resected tissue was subjected to histopathological evaluation...

  12. Transrectal high-intensity focused ultrasound (HIFU) treatment of localized prostate cancer: Review of technical incidents and morbidity after 5 years of use

    OpenAIRE

    RIPERT, Thomas; AZEMAR, Marie Dominique; MENARD, Johann; BAYOUD, Younes; Messaoudi, Rabah; Duval, François; Staerman, Frédéric

    2010-01-01

    Abstract OBJECTIVE To report on technical incidents, and early and late complications, occurring on high-intensity focused ultrasound (HIFU) treatment of patients with localized prostate cancer. PATIENTS AND METHODS We performed a retrospective review of patients who were treated by Ablatherm? in our centre. We recorded all technical incidents, treatment discontinuations, and early (< 1 month) and late complications. RESULTS A total of 74 HIFU procedures were perfor...

  13. The feasibility and safety of high-intensity focused ultrasound combined with low-dose external beam radiotherapy as supplemental therapy for advanced prostate cancer following hormonal therapy

    OpenAIRE

    Wu, Rui-Yi; Wang, Guo-Min; Xu, Lei; ZHANG, BO-HENG; Xu, Ye-Qing; Zeng, Zhao-Chong; Chen, Bing

    2011-01-01

    The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound (HIFU) combined with (+) low-dose external beam radiotherapy (LRT) as supplemental therapy for advanced prostate cancer (PCa) following hormonal therapy (HT). Our definition of HIFU+LRT refers to treating primary tumour lesions with HIFU in place of reduced field boost irradiation to the prostate, while retaining four-field box irradiation to the pelvis in conventional-dose external beam r...

  14. An optimum method for pulsed high intensity focused ultrasound treatment of large volumes using the InSightec ExAblate (registered) 2000 system

    International Nuclear Information System (INIS)

    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.

  15. Targeting accuracy and closing timeline of the microbubble-enhanced focused ultrasound blood-brain barrier opening in non-human primates

    Science.gov (United States)

    Marquet, Fabrice; Tung, Yao-Sheng; Teichert, Tobias; Wu, Shih-Ying; Wang, Shutao; Downs, Matthew; Ferrera, Vincent P.; Konofagou, Elisa E.

    2012-11-01

    The delivery of drugs to specific neural targets faces two fundamental problems: Most drugs do not cross the blood-brain barrier and those that do spread to all parts of the brain. To date there exists only one non-invasive methodology with the potential to solve these problems: selective blood-brain barrier disruption using micro-bubble enhanced focused ultrasound. We have recently developed a single-element 500 kHz spherical transducer ultrasound setup for use in the non-human primate. Using this system for selective blood-brain barrier disruption is technically no more challenging than positioning a TMS coil, and does not rely on MRI-guided targeting or expensive phased array ultrasound systems. So far, however, the targeting accuracy that can be achieved with this system has not been quantified systematically. Here we tested the accuracy of the system by targeting the caudate nucleus of the basal ganglia in two macaque monkeys. Our results show that average in-plane error of the system is on the order of 2 mm and targeting error in depth, i.e., along the ultrasound path, is even smaller and averaged 1.2 mm. In summary, targeting accuracy of our system is good enough to enable the selective delivery of drugs to specific sub-structures of the basal ganglia.

  16. Tandem focused ultrasound (TFU) combined with fast furnace analysis as an improved methodology for total mercury determination in human urine by electrothermal-atomic absorption spectrometry.

    Science.gov (United States)

    Capelo, J L; Dos Reis, C D; Maduro, C; Mota, A

    2004-09-01

    A new sample preparation procedure based on tandem (that is, different diameter probe sonicators used in the same sample treatment) focused ultrasound (TFU) for mercury separation, preconcentration and back-extraction in aqueous solution from human urine has been developed. The urine is first oxidized with KMnO(4)/HCl/focused ultrasound (6mm probe). Secondly, the mercury is extracted and preconcentrated with dithizone and cyclohexane. Finally, the mercury is back-extracted and preconcentrated again with the aid of focused ultrasound (3mm probe). The procedure allows determining mercury by electrothermal atomic absorption spectrometry with fast furnace analysis and calibration against aqueous standards. Matrix modification is provided by the chemicals used in the sample treatment. The procedure is accomplished with low sample volume (8.5ml). Low volume and low concentration reagents are used. The sample treatment is rapid (less than 3min per sample) and avoids the use of organic phase in the graphite furnace. The preconcentration factor used in this work was 14. The limit of detection and the limit of quantification in urine were, respectively, 0.27 and 0.9mugl(-1). The relative standard deviation of aqueous standards (n=10) was 4% for a concentration of 100mugl(-1) and 5% for a concentration of 400mugl(-1). Recoveries from spiked urine with inorganic mercury, methyl-mercury, phenyl-mercury and diphenyl-mercury ranged from 86 to 98%.

  17. Harmonic motion imaging for abdominal tumor detection and high-intensity focused ultrasound ablation monitoring: an in vivo feasibility study in a transgenic mouse model of pancreatic cancer.

    Science.gov (United States)

    Chen, Hong; Hou, Gary Y; Han, Yang; Payen, Thomas; Palermo, Carmine F; Olive, Kenneth P; Konofagou, Elisa E

    2015-09-01

    Harmonic motion imaging (HMI) is a radiationforce- based elasticity imaging technique that tracks oscillatory tissue displacements induced by sinusoidal ultrasonic radiation force to assess the resulting oscillatory displacement denoting the underlying tissue stiffness. The objective of this study was to evaluate the feasibility of HMI in pancreatic tumor detection and high-intensity focused ultrasound (HIFU) treatment monitoring. The HMI system consisted of a focused ultrasound transducer, which generated sinusoidal radiation force to induce oscillatory tissue motion at 50 Hz, and a diagnostic ultrasound transducer, which detected the axial tissue displacements based on acquired radio-frequency signals using a 1-D cross-correlation algorithm. For pancreatic tumor detection, HMI images were generated for pancreatic tumors in transgenic mice and normal pancreases in wild-type mice. The obtained HMI images showed a high contrast between normal and malignant pancreases with an average peak-to-peak HMI displacement ratio of 3.2. Histological analysis showed that no tissue damage was associated with HMI when it was used for the sole purpose of elasticity imaging. For pancreatic tumor ablation monitoring, the focused ultrasound transducer was operated at a higher acoustic power and longer pulse length than that used in tumor detection to simultaneously induce HIFU thermal ablation and oscillatory tissue displacements, allowing HMI monitoring without interrupting tumor ablation. HMI monitoring of HIFU ablation found significant decreases in the peak-to-peak HMI displacements before and after HIFU ablation with a reduction rate ranging from 15.8% to 57.0%. The formation of thermal lesions after HIFU exposure was confirmed by histological analysis. This study demonstrated the feasibility of HMI in abdominal tumor detection and HIFU ablation monitoring. PMID:26415128

  18. Quantification of transient increase of the blood–brain barrier permeability to macromolecules by optimized focused ultrasound combined with microbubbles

    Directory of Open Access Journals (Sweden)

    Shi L

    2014-09-01

    Full Text Available Lingyan Shi,1 Paolo Palacio-Mancheno,1 Joseph Badami,2 Da Wi Shin,1 Min Zeng,1 Luis Cardoso,1 Raymond Tu,2 Bingmei M Fu11Department of Biomedical Engineering, 2Department of Chemical Engineering, The City College of the City University of New York, New York, NY, USAAbstract: Radioimmunotherapy using a radiolabeled monoclonal antibody that targets tumor cells has been shown to be efficient for the treatment of many malignant cancers, with reduced side effects. However, the blood–brain barrier (BBB inhibits the transport of intravenous antibodies to tumors in the brain. Recent studies have demonstrated that focused ultrasound (FUS combined with microbubbles (MBs is a promising method to transiently disrupt the BBB for the drug delivery to the central nervous system. To find the optimal FUS and MBs that can induce reversible increase in the BBB permeability, we employed minimally invasive multiphoton microscopy to quantify the BBB permeability to dextran-155 kDa with similar molecular weight to an antibody by applying different doses of FUS in the presence of MBs with an optimal size and concentration. The cerebral microcirculation was observed through a section of frontoparietal bone thinned with a micro-grinder. About 5 minutes after applying the FUS on the thinned skull in the presence of MBs for 1 minute, TRITC (tetramethylrhodamine isothiocyanate-dextran-155 kDa in 1% bovine serum albumin in mammalian Ringer’s solution was injected into the cerebral circulation via the ipsilateral carotid artery by a syringe pump. Simultaneously, the temporal images were collected from the brain parenchyma ~100–200 µm below the pia mater. Permeability was determined from the rate of tissue solute accumulation around individual microvessels. After several trials, we found the optimal dose of FUS. At the optimal dose, permeability increased by ~14-fold after 5 minutes post-FUS, and permeability returned to the control level after 25 minutes. FUS without

  19. An Experimental Study of High Intensity Focused Ultrasound on Pig's Pancreas and the Early Clinical Experience on Pancreatic Cancer

    Science.gov (United States)

    Xiong, LiuLin; Huang, XiaoBo; Yao, SongSen; Yu, JinSheng; Hwang, JooHa; Fei, XingBo; Yu, QiuHong; Xue, WeiCheng; Zheng, ZhuYing; Wang, XiaoFeng

    2007-05-01

    Objective: To investigate the feasibility and safety of high intensity focused ultrasound (HIFU) treatment of in vivo pig pancreases, and to evaluate the safety and efficacy of HIFU in the clinical treatment of pancreatic cancer in humans. Methods: HIFU was performed in 12 domestic pig pancreases in vivo with varying acoustic energies. The safety of HIFU treatments was assessed by necropsy. The pathology and microstructure of the treated pancreases were evaluated using standard histology and transmission electron microscopy. Following the animal studies 62 patients with advanced pancreas cancer were treated with 250 - 420 W of acoustic power. There were 3 patients with stage II, 23 patients with stage III, and 36 patients with stage IV disease. Results: In animal studies, precise regions of coagulation necrosis were identified on pathology in 8 specimens that were treated with 420 W or 645 W acoustic power. Treatment effects were unable to be identified in 4 specimens treated with 300˜340 W acoustic power; however, damages to the cells microstructure and apoptosis were identified on electron microscopy. Damage to the stomach and colon were seen in some animals treated with 645 W. In the clinical treatments in humans the following were seen: local tumor control: complete response (CR) 0%, partial response (PR) 17.7%, no change (NC) 54.8%, progressive disease (PD) 27.5%. Pain relief was achieved in 87.1% of patients. The median survival for stage II and III patients was 11.2 months and median survival for stage IV patients was 5.6 months. The total median survival was 8.6 months. The survival rate at 1 year was as follows: stage II and III 42.3%, stage IV 5.6%. The survival rate at 2 years was as follows: stage II and III 15.4%, stage IV 0%. There were no severe complications or adverse events related to HIFU therapy seen in any of the patients treated. Conclusions: This study supports the feasibility of HIFU in the treatment of pancreatic cancer. The clinical

  20. Dynamics of high-energy proton beam acceleration and focusing from hemisphere-cone targets by high-intensity lasers.

    Science.gov (United States)

    Qiao, B; Foord, M E; Wei, M S; Stephens, R B; Key, M H; McLean, H; Patel, P K; Beg, F N

    2013-01-01

    Acceleration and focusing of high-energy proton beams from fast-ignition (FI) -related hemisphere-cone assembled targets have been numerically studied by hybrid particle-in-cell simulations and compared with those from planar-foil and open-hemisphere targets. The whole physical process including the laser-plasma interaction has been self-consistently modeled for 15 ps, at which time the protons reach asymptotic motion. It is found that the achievable focus of proton beams is limited by the thermal pressure gradients in the co-moving hot electrons, which induce a transverse defocusing electric field that bends proton trajectories near the axis. For the advanced hemisphere-cone target, the flow of hot electrons along the cone wall induces a local transverse focusing sheath field, resulting in a clear enhancement in proton focusing; however, it leads to a significant loss of longitudinal sheath potential, reducing the total conversion efficiency from laser to protons. PMID:23410447

  1. Low-Pressure Burst-Mode Focused Ultrasound Wave Reconstruction and Mapping for Blood-Brain Barrier Opening: A Preclinical Examination

    Science.gov (United States)

    Xia, Jingjing; Tsui, Po-Hsiang; Liu, Hao-Li

    2016-06-01

    Burst-mode focused ultrasound (FUS) exposure has been shown to induce transient blood-brain barrier (BBB) opening for potential CNS drug delivery. FUS-BBB opening requires imaging guidance during the intervention, yet current imaging technology only enables postoperative outcome confirmation. In this study, we propose an approach to visualize short-burst low-pressure focal beam distribution that allows to be applied in FUS-BBB opening intervention on small animals. A backscattered acoustic-wave reconstruction method based on synchronization among focused ultrasound emission, diagnostic ultrasound receiving and passively beamformed processing were developed. We observed that focal beam could be successfully visualized for in vitro FUS exposure with 0.5–2 MHz without involvement of microbubbles. The detectable level of FUS exposure was 0.467 MPa in pressure and 0.05 ms in burst length. The signal intensity (SI) of the reconstructions was linearly correlated with the FUS exposure level both in-vitro (r2 = 0.9878) and in-vivo (r2 = 0.9943), and SI level of the reconstructed focal beam also correlated with the success and level of BBB-opening. The proposed approach provides a feasible way to perform real-time and closed-loop control of FUS-based brain drug delivery.

  2. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging

    Science.gov (United States)

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-09-01

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.

  3. Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging.

    Science.gov (United States)

    Chu, Po-Chun; Chai, Wen-Yen; Tsai, Chih-Hung; Kang, Shih-Tsung; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-01-01

    Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery. PMID:27630037

  4. Design, simulation and construction of quadrupole magnets for focusing electron beam in powerful industrial electron accelerator

    OpenAIRE

    S KH Mousavi; A M Poursaleh; S Haseltalab; M Mortazavi; A Behjat; Atefi, M.

    2015-01-01

    In this paper the design and simulation of quadrupole magnets and electron beam optical of that by CST Studio code has been studied. Based on simulation result the magnetic quadrupole has been done for using in beam line of first Iranian powerful electron accelerator. For making the suitable magnetic field the effects of material and core geometry and coils current variation on quadrupole magnetic field have been studied. For test of quadrupole magnet the 10 MeV beam energy and 0.5 pi mm...

  5. Experimental study with high intensity focused ultrasound in swine vulva%高强度聚焦超声致香猪外阴损伤的研究

    Institute of Scientific and Technical Information of China (English)

    阮祥燕; 顾美礼; 王智彪

    2000-01-01

    目的 观察高强度聚焦超声(HIFU)对香猪外阴的损伤作用及愈合过程,旨在为外阴营养不良探索新的治疗方法.方法 对5只小型香猪的外阴进行HIFU(频率9.84 MHz,声强1 109 W/cm2)连续扫描定位损伤.HIFU辐照后即刻、3 d、7 d、14 d、21 d、30 d行彩超、病理检查,动态监测其损伤变化情况.结果 HIFU可准确定位损伤靶区组织,其相临表面皮肤组织不受损伤.HIFU后靶区超声影像学变化与病理学变化一致.结论 HIFU损伤猪外阴安全有效,为临床外阴营养不良的治疗提供了实验依据;彩超可监测HIFU致外阴治疗的情况.%Objective In order to explore a new method for the treatment of human vulva dystrophy,swine vulva were treated with high intensity focused ultrasound(HIFU).Methods A 9.84 MHz high intensity focused ultrasound at an intensity of 1 109 W/cm2 with continuous exposure was applied in 5 female swine.After HIFU lesions developed,the outcomes were assessed by color ultrasound and the pathological examination immediately and on day 3,7.14,21 and 30.Results HIFU was competent for damaging precisely the target tissue of the vulva and disrupting irreversibly the cellular structure in the focal region leaving the intact surface skin of the target region.A change of ultrasound in the focused region was coincident with that of the pathology.Conclusions HIFU has the powerful effect of accurately destroying vulva tissue and keeping the surface skin intact.The results provided an experimental basis for the clinical treatment of vulva dystrophy.Color ultrasound will become a useful tool in monitoring the outcome after HIFU treatment.

  6. Challenges in Linear Accelerator Radiotherapy for Chordomas and Chondrosarcomas of the Skull Base: Focus on Complications

    Energy Technology Data Exchange (ETDEWEB)

    Hauptman, Jason S., E-mail: jhauptman@mednet.ucla.edu [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Barkhoudarian, Garni; Safaee, Michael; Gorgulho, Alessandra [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Tenn, Steven; Agazaryan, Nzhde; Selch, Michael [Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); De Salles, Antonio A.F. [Division of Stereotactic and Functional Neurosurgery, Department of Neurosurgery, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States); Department of Radiation Oncology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA (United States)

    2012-06-01

    Purpose: Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that infiltrate the skull base. Currently, consensus therapy includes surgical resection and adjuvant radiotherapy. Radiation delivery is typically limited by the proximity of these tumors to critical skull base structures. Methods: This is a retrospective review of 13 cases of chordomas and 2 cases of chondroid chondrosarcomas of the skull based treated with linear accelerator stereotactic radiotherapy (SRT, n = 10) or stereotactic radiosurgery (SRS, n = 5). The average time to the most recent follow-up visit was 4.5 years. The tumor characteristics, treatment details, and outcomes were recorded. Each radiation plan was reviewed, and the dosage received by the brainstem, optic apparatus, and pituitary was calculated. Results: Of the 10 patients treated with SRT, 6 were found to have unchanged or decreased tumor size as determined from radiographic follow-up. Of the 5 patients treated with SRS, 3 were found to have stable or unchanged tumors at follow-up. The complications included 1 SRT patient who developed endocrinopathy, 2 patients (1 treated with SRS and the other with SRT), who developed cranial neuropathy, and 1 SRS patient who developed visual deficits. Additionally, 1 patient who received both SRS and SRT within 2 years for recurrence experienced transient medial temporal lobe radiation changes that resolved. Conclusions: Where proton beam therapy is unavailable, linear accelerator-based SRT or radiosurgery remains a safe option for adjuvant therapy of chordomas and chondrosarcomas of the skull base. The exposure of the optic apparatus, pituitary stalk, and brainstem must be considered during planning to minimize complications. If the optic apparatus is included in the 80% isodose line, it might be best to fractionate therapy. Exposure of the pituitary stalk should be kept to <30 Gy to minimize endocrine dysfunction. Brainstem exposure should be

  7. Challenges in Linear Accelerator Radiotherapy for Chordomas and Chondrosarcomas of the Skull Base: Focus on Complications

    International Nuclear Information System (INIS)

    Purpose: Intracranial chordomas and chondrosarcomas are histologically low-grade, locally invasive tumors that infiltrate the skull base. Currently, consensus therapy includes surgical resection and adjuvant radiotherapy. Radiation delivery is typically limited by the proximity of these tumors to critical skull base structures. Methods: This is a retrospective review of 13 cases of chordomas and 2 cases of chondroid chondrosarcomas of the skull based treated with linear accelerator stereotactic radiotherapy (SRT, n = 10) or stereotactic radiosurgery (SRS, n = 5). The average time to the most recent follow-up visit was 4.5 years. The tumor characteristics, treatment details, and outcomes were recorded. Each radiation plan was reviewed, and the dosage received by the brainstem, optic apparatus, and pituitary was calculated. Results: Of the 10 patients treated with SRT, 6 were found to have unchanged or decreased tumor size as determined from radiographic follow-up. Of the 5 patients treated with SRS, 3 were found to have stable or unchanged tumors at follow-up. The complications included 1 SRT patient who developed endocrinopathy, 2 patients (1 treated with SRS and the other with SRT), who developed cranial neuropathy, and 1 SRS patient who developed visual deficits. Additionally, 1 patient who received both SRS and SRT within 2 years for recurrence experienced transient medial temporal lobe radiation changes that resolved. Conclusions: Where proton beam therapy is unavailable, linear accelerator-based SRT or radiosurgery remains a safe option for adjuvant therapy of chordomas and chondrosarcomas of the skull base. The exposure of the optic apparatus, pituitary stalk, and brainstem must be considered during planning to minimize complications. If the optic apparatus is included in the 80% isodose line, it might be best to fractionate therapy. Exposure of the pituitary stalk should be kept to <30 Gy to minimize endocrine dysfunction. Brainstem exposure should be

  8. Photoacoustic detection and optical spectroscopy of high-intensity focused ultrasound-induced thermal lesions in biologic tissue

    Energy Technology Data Exchange (ETDEWEB)

    Alhamami, Mosa; Kolios, Michael C.; Tavakkoli, Jahan, E-mail: jtavakkoli@ryerson.ca [Department of Physics, Ryerson University, 350 Victoria Street, Toronto, Ontario M5B 2K3 (Canada)

    2014-05-15

    Purpose: The aims of this study are: (a) to investigate the capability of photoacoustic (PA) method in detecting high-intensity focused ultrasound (HIFU) treatments in muscle tissuesin vitro; and (b) to determine the optical properties of HIFU-treated and native tissues in order to assist in the interpretation of the observed contrast in PA detection of HIFU treatments. Methods: A single-element, spherically concaved HIFU transducer with a centre frequency of 1 MHz was utilized to create thermal lesions in chicken breast tissuesin vitro. To investigate the detectability of HIFU treatments photoacoustically, PA detection was performed at 720 and 845 nm on seven HIFU-treated tissue samples. Within each tissue sample, PA signals were acquired from 22 locations equally divided between two regions of interest within two volumes in tissue – a HIFU-treated volume and an untreated volume. Optical spectroscopy was then carried out on 10 HIFU-treated chicken breast specimens in the wavelength range of 500–900 nm, in 1-nm increments, using a spectrophotometer with an integrating sphere attachment. The authors’ optical spectroscopy raw data (total transmittance and diffuse reflectance) were used to obtain the optical absorption and reduced scattering coefficients of HIFU-induced thermal lesions and native tissues by employing the inverse adding-doubling method. The aforementioned interaction coefficients were subsequently used to calculate the effective attenuation coefficient and light penetration depth of HIFU-treated and native tissues in the wavelength range of 500–900 nm. Results: HIFU-treated tissues produced greater PA signals than native tissues at 720 and 845 nm. At 720 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.68 ± 0.25 (mean ± standard error of the mean). At 845 nm, the averaged ratio of the peak-to-peak PA signal amplitude of HIFU-treated tissue to that of native tissue was 3.75

  9. Single session of high-intensity focused ultrasound for localized prostate cancer: treatment outcomes and potential effect as a primary therapy

    OpenAIRE

    KOMURA, KAZUMASA; Inamoto, Teruo; Takai, Tomoaki; Uchimoto, Taizo; Saito, Kenkichi; Tanda, Naoki; Kono, Junko; Minami, Koichiro; Uehara, Hirohumi; Fujisue, Yutaka; Takahara, Kiyoshi; Hirano, Hajime; Nomi, Hayahito; WATSUJI, TOSHIKAZU; Kiyama, Satoshi

    2013-01-01

    Purpose To investigate the treatment outcomes of a single-session high-intensity focused ultrasound (HIFU) using the Sonablate® for patients with localized prostate cancer. Methods Biochemical failure was defined according to the Stuttgart definition [a rise of 1.2 ng/ml or more above the nadir prostate-specific antigen (PSA)] and the Phoenix definition (a rise of 2 ng/ml or more above the nadir PSA). Disease-free survival rate was defined using the Phoenix criteria and positive follow-up bio...

  10. First Clinical Experience of Intra-Operative High Intensity Focused Ultrasound in Patients with Colorectal Liver Metastases: A Phase I-IIa Study

    OpenAIRE

    Aurélien Dupré; David Melodelima; David Pérol; Yao Chen; Jérémy Vincenot; Jean-Yves Chapelon; Michel Rivoire

    2015-01-01

    Background Surgery is the only curative treatment in patients with colorectal liver metastases (CLM), but only 10–20% of patients are eligible. High Intensity Focused Ultrasound (HIFU) technology is of proven value in several indications, notably prostate cancer. Its intra-operative use in patients with CLM has not previously been studied. Preclinical work suggested the safety and feasibility of a new HIFU device capable of ablating volumes of up to 2cm x 2cm in a few seconds. Methods We cond...

  11. Focal therapy with high-intensity focused ultrasound for prostate cancer in the elderly: a feasibility study with 10 years follow-up

    OpenAIRE

    Amine B. El Fegoun; Eric Barret; Dominique Prapotnich; Shawn Soon; Xavier Cathelineau; François Rozet; Marc Galiano; Rafael Sanchez-Salas; Guy Vallancien

    2011-01-01

    PURPOSE: To evaluate the long-term efficacy of prostate cancer control and complication rates, in the elderly, after focal therapy with high-intensity focused ultrasound (HIFU). MATERIALS AND METHODS: Between June 1997 and March 2000, patients with localized prostate cancer were included into a focal therapy protocol. Inclusion criteria were: PSA < 10 ng/mL, < 3 positive biopsies with only 1 lobe involved, clinical stage < T2a, Gleason score < 7 (3+4), negative CT scan and bone scan. Hemi-abl...

  12. Modeling of ultrasound transducers

    DEFF Research Database (Denmark)

    Bæk, David

    This Ph.D. dissertation addresses ultrasound transducer modeling for medical ultrasound imaging and combines the modeling with the ultrasound simulation program Field II. The project firstly presents two new models for spatial impulse responses (SIR)s to a rectangular elevation focused transducer...

  13. Optimisation and characterisation of marihuana extracts obtained by supercritical fluid extraction and focused ultrasound extraction and retention time locking GC-MS.

    Science.gov (United States)

    Omar, Jone; Olivares, Maitane; Alzaga, Mikel; Etxebarria, Nestor

    2013-04-01

    The optimisation of focused ultrasound extraction and supercritical fluid extraction of volatile oils and cannabinoids from marihuana has been accomplished by experimental design approach. On the one hand, the focused ultrasound extraction method of volatile compounds and cannabinoids was studied based on the optimisation of cyclohexane and isopropanol solvent mixtures, and the instrumental variables. The optimal working conditions were finally fixed at isopropanol/cyclohexane 1:1 mixture, cycles (3 s(-1)), amplitude (80%) and sonication time (5 min). On the other hand, the supercritical fluid extraction method was optimised in order to obtain a deterpenation of the plant and a subsequent cannabinoid extraction. For this purpose, pressure, temperature, flow and co-solvent percentage were optimised and the optimal working conditions were set at 100 bar, 35°C, 1 mL/min, no co-solvent for the terpenes and 20% of ethanol for the cannabinoids. Based on the retention time locking GC-MS analysis of the supercritical fluid extracts the classification of the samples according to the type of plant, the growing area and season was attained. Finally, three monoterpenes and three cannabinoids were quantified in the ranges of 0.006-6.2 μg/g and 0.96-324 mg/g, respectively.

  14. Feedback control of temperature evolution in rabbit kidney in vivo using MRI guided focused ultrasound. Application to renal VX2 carcinoma ablation

    Science.gov (United States)

    Delemazure, A. S.; Salomir, R.; Grenier, N.; Palussière, J.; Deminière, C.; Mougenot, C.; Moonen, C. W.

    2005-03-01

    A significant number of patients with small renal tumours may get benefit from in situ thermo-ablation techniques. Focused ultrasound is a non-invasive approach which offers excellent flexibility. On the other hand, real time MR thermometry is a valuable tool for monitoring and controlling therapy. In this study, coupling of focused ultrasound with PRF-based, respiratory-gated MR thermometry was used to provide temperature feedback control for local hyperthermia in the rabbit kidney. Two heating protocols were initially used in healthy kidneys (medulla and cortex): 1. fixed focal point heating; 2. spiral trajectories of the focal point. Further, five VX2 renal carcinomas were treated with multiple focal point heating in each tumour. Post-treatment MRI follow up and post mortem histology were performed. The shape and size of the lesions (MRI, histology) were compared to the calculated thermal dose map. The standard deviation of the MR thermometry ranged from 0.5°C to 1°C. The temperature controller matched the objective curve with approximately 1°C precision (fixed focal point mode). Several technical and physiological difficulties for spiral heating could not be overcome with the available setup. Thermal ablation with temperature feedback control in healthy and tumour bearing kidney was demonstrated to be feasible and effective, despite specific challenges (deep seated organ, respiratory motion, high blood perfusion).

  15. Transient disruption of vascular barriers using focused ultrasound and microbubbles for targeted drug delivery in the brain

    Science.gov (United States)

    Aryal, Muna

    The physiology of the vasculature in the central nervous system (CNS) which includes the blood-brain-barrier (BBB) and other factors, prevents the transport of most anticancer agents to the brain and restricts delivery to infiltrating brain tumors. The heterogeneous vascular permeability in tumor vessels (blood-tumor barrier; BTB), along with several other factors, creates additional hurdles for drug treatment of brain tumors. Different methods have been used to bypass the BBB/BTB, but they have their own limitations such as being invasive, non-targeted or requiring the formulation of new drugs. Magnetic Resonance Imaging guided Focused Ultrasound (MRIgFUS), when combined with circulating microbubbles, is an emerging noninvasive method to temporarily permeabilize the BBB and BTB. The purpose of this thesis was to use this alternative approach to deliver chemotherapeutic agents through the BBB/BTB for brain tumor treatment in a rodent model to overcome the hinderances encountered in prior approaches tested for drug delivery in the CNS. The results presented in thesis demonstrate that MRIgFUS can be used to achieve consistent and reproducible BBB/BTB disruption in rats. It enabled us to achieve clinically-relevant concentrations of doxorubicin (~ 4.8+/-0.5 microg/g) delivered to the brain with the sonication parameters (0.69 MHz; 0.55 MPa; 10 ms bursts; 1 Hz PRF; 60 s duration), microbubble concentration (Definity, 10 microl/kg), and liposomoal doxorubicin (Lipo-DOX) dose (5.67 mg/kg) used. The resulting doxorubicin concentration was reduced by 32% when the agent was injected 10 minute after the last sonication. Three weekly sessions of FUS and Lipo-DOX appeared to be safe in the rat brain, despite some minor tissue damage. Importantly, the severe neurotoxicity seen in earlier works using other approaches does not appear to occur with delivery via FUS-BBB disruption. The resuls from three weekly treatments of FUS and Lipo-DOX in a rat glioma model are highly

  16. 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

  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)

    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) cm3. 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) cm3, slightly enlarged because of edema. The average non-perfused volume was 83.3 ± 71.7 (range, 7.7-282.9) cm3, 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. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Ultrasound - Pelvis Ultrasound imaging of the pelvis uses sound ... limitations of Pelvic Ultrasound Imaging? What is Pelvic Ultrasound Imaging? Ultrasound is safe and painless, and produces ...

  19. Prostate Ultrasound

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Ultrasound - Prostate Ultrasound of the prostate uses sound waves ... the limitations of Prostate Ultrasound Imaging? What is Ultrasound Imaging of the Prostate? Ultrasound is safe and ...

  20. Ultrasound -- Pelvis

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Ultrasound - Pelvis Ultrasound imaging of the pelvis uses sound ... limitations of Pelvic Ultrasound Imaging? What is Pelvic Ultrasound Imaging? Ultrasound is safe and painless, and produces ...

  1. Influence of Accelerated Solvent Extraction and Ultrasound-Assisted Extraction on the Anthocyanin Profile of Different Vaccinium Species in the Context of Statistical Models for Authentication.

    Science.gov (United States)

    Heffels, Peter; Weber, Fabian; Schieber, Andreas

    2015-09-01

    Anthocyanins are frequently discussed as marker compounds for fruit product authenticity. Proper analysis including sample preparation for the determination of anthocyanin concentrations is crucial for the comparability of authenticity data. The present study determined the influence of accelerated solvent extraction (ASE) and ultrasound-assisted extraction (UAE), using two different solvent compositions on the anthocyanin profile of bilberries (Vaccinium myrtillus L.), lowbush blueberries (Vaccinium angustifolium Ait.), and American cranberries (Vaccinium macrocarpon Ait.). Besides differences in total anthocyanin concentrations in the extracts, significant deviations (p ≤ 0.05) in the individual anthocyanin concentration were observed, resulting in differing anthocyanin proportions. Linear discriminant analysis comparing the differences caused by the extraction method to the natural differences within a set of 26 bilberry and lowbush blueberry samples of different origins was conducted. It revealed that profile variations induced by the extraction methods are in a similar scale to profile variations as a result of geographic and climatic differences. PMID:26330254

  2. Clinical utility of a microbubble-enhancing contrast (“SonoVue”) in treatment of uterine fibroids with high intensity focused ultrasound: A retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Song [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); Xiong, Yu [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); Li, Kequan [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); He, Min [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); Deng, Yongbin; Chen, Li; Zou, Min [Department of Obstetrics of Chongqing Haifu Hospital, Chongqing 401121 (China); Chen, Wenzhi; Wang, Zhibiao [State Key Laboratory of Ultrasound Engineering in Medicine Co-founded by Chongqing and the Ministry of Science and Technology, Chongqing Key Laboratory of Ultrasound in Medicine and Engineering, Department of Biomedical Engineering, Chongqing Medical University, Chongqing 400016 (China); Non-invasive and Minimally Invasive Therapeutic Research Center for Uterine Benign Diseases of Chongqing, Chongqing 401121 (China); He, Jia, E-mail: hejia0820@sina.com.cn [Department of Obstetrics and Gynecology, Suining Central Hospital, Sichuan 629000 (China); and others

    2012-12-15

    Purpose: To evaluate the clinical value of the contrast agent SonoVue in the treatment of uterine fibroids with ultrasound-guided high intensity focused ultrasound (HIFU) therapeutic ablation. Materials and Methods: A total of 291 patients with solitary uterine fibroid from three centers were treated with ultrasound-guided HIFU. Among them, 129 patients from Suining Central Hospital of Sichuan were treated without using SonoVue. 162 patients from the First Hospital of Chongqing Medical University and Chongqing Haifu Hospital were treated with using SonoVue before, during and after HIFU procedure to assess the extent of HIFU. Results: The non-perfused volume (indicative of successful ablation) was observed in all treated uterine fibroids immediately after HIFU ablation; median fractional ablation, defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 86.0% (range, 28.8–100.0%) in the group with using SonoVue, and 83.0% (8.7–100.0%) without SonoVue. The rate of massive gray scale changes was higher with SonoVue than without the agent. The sonication time to achieve massive gray scale changes was shorter with SonoVue than without. The sonication time for ablating 1 cm{sup 3} of fibroid volume was significantly shorter with using SonoVue than without. No major complications were observed in any patients. Conclusions: Based on our results, SonoVue may enhance the outcome of HIFU ablation and can be used to assess the extent of treatment.

  3. Portable high-intensity focused ultrasound system with 3D electronic steering, real-time cavitation monitoring, and 3D image reconstruction algorithms: a preclinical study in pigs

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Woo; Lee, Jae Young; Hwang, Eui Jin; Hwang, In Pyeong; Woo, Sung Min; Lee, Chang Joo; Park, Eun Joo; Choi, Byung Ihn [Dept. of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-10-15

    The aim of this study was to evaluate the safety and accuracy of a new portable ultrasonography-guided high-intensity focused ultrasound (USg-HIFU) system with a 3-dimensional (3D) electronic steering transducer, a simultaneous ablation and imaging module, real-time cavitation monitoring, and 3D image reconstruction algorithms. To address the accuracy of the transducer, hydrophones in a water chamber were used to assess the generation of sonic fields. An animal study was also performed in five pigs by ablating in vivo thighs by single-point sonication (n=10) or volume sonication (n=10) and ex vivo kidneys by single-point sonication (n=10). Histological and statistical analyses were performed. In the hydrophone study, peak voltages were detected within 1.0 mm from the targets on the y- and z-axes and within 2.0-mm intervals along the x-axis (z-axis, direction of ultrasound propagation; y- and x-axes, perpendicular to the direction of ultrasound propagation). Twenty-nine of 30 HIFU sessions successfully created ablations at the target. The in vivo porcine thigh study showed only a small discrepancy (width, 0.5-1.1 mm; length, 3.0 mm) between the planning ultrasonograms and the pathological specimens. Inordinate thermal damage was not observed in the adjacent tissues or sonic pathways in the in vivo thigh and ex vivo kidney studies. Our study suggests that this new USg-HIFU system may be a safe and accurate technique for ablating soft tissues and encapsulated organs.

  4. Clinical utility of a microbubble-enhancing contrast (“SonoVue”) in treatment of uterine fibroids with high intensity focused ultrasound: A retrospective study

    International Nuclear Information System (INIS)

    Purpose: To evaluate the clinical value of the contrast agent SonoVue in the treatment of uterine fibroids with ultrasound-guided high intensity focused ultrasound (HIFU) therapeutic ablation. Materials and Methods: A total of 291 patients with solitary uterine fibroid from three centers were treated with ultrasound-guided HIFU. Among them, 129 patients from Suining Central Hospital of Sichuan were treated without using SonoVue. 162 patients from the First Hospital of Chongqing Medical University and Chongqing Haifu Hospital were treated with using SonoVue before, during and after HIFU procedure to assess the extent of HIFU. Results: The non-perfused volume (indicative of successful ablation) was observed in all treated uterine fibroids immediately after HIFU ablation; median fractional ablation, defined as non-perfused volume divided by the fibroid volume immediately after HIFU treatment, was 86.0% (range, 28.8–100.0%) in the group with using SonoVue, and 83.0% (8.7–100.0%) without SonoVue. The rate of massive gray scale changes was higher with SonoVue than without the agent. The sonication time to achieve massive gray scale changes was shorter with SonoVue than without. The sonication time for ablating 1 cm3 of fibroid volume was significantly shorter with using SonoVue than without. No major complications were observed in any patients. Conclusions: Based on our results, SonoVue may enhance the outcome of HIFU ablation and can be used to assess the extent of treatment.

  5. Drug-loaded bubbles with matched focused ultrasound excitation for concurrent blood-brain barrier opening and brain-tumor drug delivery.

    Science.gov (United States)

    Fan, Ching-Hsiang; Ting, Chien-Yu; Chang, Yuan-Chih; Wei, Kuo-Chen; Liu, Hao-Li; Yeh, Chih-Kuang

    2015-03-01

    Focused ultrasound (FUS) with microbubbles has been used to achieve local blood-brain barrier opening (BBB opening) and increase the penetration of therapeutic drugs into brain tumors. However, inertial cavitation of microbubbles during FUS-induced BBB opening causes intracerebral hemorrhaging (ICH), leading to acute and chronic brain injury and limiting the efficiency of drug delivery. Here we investigated whether induction of drug (1,3-bis(2-chloroethyl)-1-nitrosourea, BCNU)-loaded bubbles (BCNU bubbles) to oscillate at their resonant frequency would reduce inertial cavitation during BBB opening, thereby eliminating ICH and enhancing drug delivery in a rat brain model. FUS was tested at 1 and 10 MHz, over a wide range of pressure (mechanical index ranging from 0.16 to 1.42) in the presence of BCNU bubbles. Excitation of BCNU bubbles by resonance frequency-matched FUS (10 MHz) resulted in predominantly stable cavitation and significantly reduced the occurrence of potential hazards of exposure to biological tissues during the BBB opening process. In addition, the drug release process could be monitored by acoustic emission obtained from ultrasound imaging. In tumor-bearing animals, BCNU bubbles with FUS showed significant control of tumor progression and improved maximum survival from 26 to 35 days. This study provides useful advancements toward the goal of successfully translating FUS theranostic bubble-enhanced brain drug delivery into clinical use.

  6. The safety and feasibility of extracorporeal high-intensity focused ultrasound (HIFU) for the treatment of liver and kidney tumours in a Western population.

    Science.gov (United States)

    Illing, R O; Kennedy, J E; Wu, F; ter Haar, G R; Protheroe, A S; Friend, P J; Gleeson, F V; Cranston, D W; Phillips, R R; Middleton, M R

    2005-10-17

    High-intensity focused ultrasound (HIFU) provides a potential noninvasive alternative to conventional therapies. We report our preliminary experience from clinical trials designed to evaluate the safety and feasibility of a novel, extracorporeal HIFU device for the treatment of liver and kidney tumours in a Western population. The extracorporeal, ultrasound-guided Model-JC Tumor Therapy System (HAIFU Technology Company, China) has been used to treat 30 patients according to four trial protocols. Patients with hepatic or renal tumours underwent a single therapeutic HIFU session under general anaesthesia. Magnetic resonance imaging 12 days after treatment provided assessment of response. The patients were subdivided into those followed up with further imaging alone or those undergoing surgical resection of their tumours, which enabled both radiological and histological assessment. HIFU exposure resulted in discrete zones of ablation in 25 of 27 evaluable patients (93%). Ablation of liver tumours was achieved more consistently than for kidney tumours (100 vs 67%, assessed radiologically). The adverse event profile was favourable when compared to more invasive techniques. HIFU treatment of liver and kidney tumours in a Western population is both safe and feasible. These findings have significant implications for future noninvasive image-guided tumour ablation. PMID:16189519

  7. Spatial specificity and sensitivity of passive cavitation imaging for monitoring high-intensity focused ultrasound thermal ablation in ex vivo bovine liver

    Science.gov (United States)

    Haworth, Kevin; Salgaonkar, Vasant A.; Corregan, Nicholas M.; Holland, Christy K.; Mast, T. D.

    2014-01-01

    Passive cavitation images (PCIs) generated from scattered acoustic waves are a potential technique for monitoring lesion formation during high-intensity focused ultrasound (HIFU) thermal ablation. HIFU lesion prediction by PCIs was assessed in ex vivo bovine liver samples (N=14) during 30-s sonications with 1.1-MHz continuous-wave ultrasound (1989 W/cm^2 estimated spatial-peak intensity). Treated samples were sectioned, optically scanned, and the HIFU lesions segmented based on tissue discoloration. During each insonation, a 192-element, 7-MHz linear array (L7/Iris 2, Ardent Sound) passively recorded emissions from a plane containing the HIFU propagation axis oriented parallel to the image azimuth direction. PCIs were formed from beamformed A-lines filtered into fundamental, harmonic, ultraharmonic, and inharmonic frequency bands. Lesion prediction was tested using binary classification of local tissue ablation based on thresholded PCIs, with spatial specificity and sensitivity of lesion prediction quantified by the area under receiver operating characteristic curves (AUROC). Tadpole-shaped lesions were best predicted by harmonic emissions (AUROC=0.76), prefocal lesions were best predicted by harmonic or ultraharmonic emissions (AUROC=0.86), and cigar-type focal lesions were best predicted by fundamental and harmonic emissions (AUROC=0.65). These results demonstrate spatial specificity and sensitivity when predicting HIFU lesions with PCIs. PMID:24817990

  8. Real-time monitoring of focused ultrasound blood-brain barrier opening via subharmonic acoustic emission detection: implementation of confocal dual-frequency piezoelectric transducers

    Science.gov (United States)

    Tsai, Chih-Hung; Zhang, Jia-Wei; Liao, Yi-Yi; Liu, Hao-Li

    2016-04-01

    Burst-tone focused ultrasound exposure in the presence of microbubbles has been demonstrated to be effective at inducing temporal and local opening of the blood-brain barrier (BBB), which promises significant clinical potential to deliver therapeutic molecules into the central nervous system (CNS). Traditional contrast-enhanced imaging confirmation after focused ultrasound (FUS) exposure serves as a post-operative indicator of the effectiveness of FUS-BBB opening, however, an indicator that can concurrently report the BBB status and BBB-opening effectiveness is required to provide effective feedback to implement this treatment clinically. In this study, we demonstrate the use of subharmonic acoustic emission detection with implementation on a confocal dual-frequency piezoelectric ceramic structure to perform real-time monitoring of FUS-BBB opening. A confocal dual-frequency (0.55 MHz/1.1 MHz) focused ultrasound transducer was designed. The 1.1 MHz spherically-curved ceramic was employed to deliver FUS exposure to induce BBB-opening, whereas the outer-ring 0.55 MHz ceramic was employed to detect the subharmonic acoustic emissions originating from the target position. In stage-1 experiments, we employed spectral analysis and performed an energy spectrum density (ESD) calculation. An optimized 0.55 MHz ESD level change was shown to effectively discriminate the occurrence of BBB-opening. Wideband acoustic emissions received from 0.55 MHz ceramics were also analyzed to evaluate its correlations with erythrocyte extravasations. In stage-2 real-time monitoring experiments, we applied the predetermined ESD change as a detection threshold in PC-controlled algorithm to predict the FUS exposure intra-operatively. In stage-1 experiment, we showed that subharmonic ESD presents distinguishable dynamics between intact BBB and opened BBB, and therefore a threshold ESD change level (5.5 dB) can be identified for BBB-opening prediction. Using this ESD change threshold detection as a

  9. Dual-modality image guided high intensity focused ultrasound device design for prostate cancer: A numerical study

    Science.gov (United States)

    Hobson, Dexter; Curiel, Laura; Chapelon, Jean-Yves; Pichardo, Samuel

    2012-10-01

    In this study the feasibility of designing a multi-element prostate cancer treatment device using Magnetic Resonance Imaging and ultrasound imaging for guidance was determined. A parametric study was performed to determine the optimal focal length (L), operating frequency (f), element size (a) and central hole radius for lodging an imaging probe (r) of a device that would safely treat cancerous tissue within the prostate. Images from the Visible Human Project were used to determine simulated organ sizes and treatment locations. Elliptical tumors were placed throughout the simulated prostate and their lateral and axial limits were selected as test locations. Using Tesla C1060 (NVIDIA, Santa Clara, CA, USA) graphics processors, the Bio-Heat Transfer Equation was implemented to calculate the heating produced during the simulated treatment. L, f a and r were varied from 45 to 75mm, 2.25 to 3.00MHz, 1.5 to 8 times λ and 9 to 11mm, respectively. Results indicated that a device of 761 elements with a combination of L, f a and r of 68mm, 2.75MHz, 2.05λ and 9mm, respectively, could safely ablate tumors within the prostate and spare the surrounding organs.

  10. High-Intensity Focused Ultrasound (HIFU) Using Sonablate® Devices for the Treatment of Benign Prostatic Hyperplasia and Localized Prostate Cancer: 18-year experience

    Science.gov (United States)

    Uchida, Toyoaki

    2011-09-01

    From 1993 to 2010, we have treated 156 patients benign prostatic hyperplasia (BPH) and 1,052 patients localized prostate cancer high-intensity focused ultrasound (HIFU). Four different HIFU devices, SonablateR-200, SonablateR-500, SonablateR-500 version 4 and Sonablate® TCM, have been used for this study. Clinical outcome of HIFU for BPH did not show any superior effects to transurethral resection of the prostate, laser surgery or transurethral vapolization of the prostate. However, HIFU appears to be a safe and minimally invasive therapy for patients with localized prostate cancer, especially low- and intermediate-risk patients. The rate of clinical outcome has significantly improved over the years due to technical improvements in the device.

  11. Therapeutic ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Crum, Lawrence A [Center for Industrial and Medical Ultrasound, 1013 NE 40th Street, University of Washington, Seattle, WA 98105 (United States)

    2004-01-01

    The use of ultrasound in medicine is now quite commonplace, especially with the recent introduction of small, portable and relatively inexpensive, hand-held diagnostic imaging devices. Moreover, ultrasound has expanded beyond the imaging realm, with methods and applications extending to novel therapeutic and surgical uses. These applications broadly include: tissue ablation, acoustocautery, lipoplasty, site-specific and ultrasound mediated drug activity, extracorporeal lithotripsy, and the enhancement of natural physiological functions such as wound healing and tissue regeneration. A particularly attractive aspect of this technology is that diagnostic and therapeutic systems can be combined to produce totally non-invasive, imageguided therapy. This general lecture will review a number of these exciting new applications of ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors as well as the introduction of acoustic hemostasis, especially in organs which are difficult to treat using conventional medical and surgical techniques. (amum lecture)

  12. Therapeutic ultrasound

    International Nuclear Information System (INIS)

    The use of ultrasound in medicine is now quite commonplace, especially with the recent introduction of small, portable and relatively inexpensive, hand-held diagnostic imaging devices. Moreover, ultrasound has expanded beyond the imaging realm, with methods and applications extending to novel therapeutic and surgical uses. These applications broadly include: tissue ablation, acoustocautery, lipoplasty, site-specific and ultrasound mediated drug activity, extracorporeal lithotripsy, and the enhancement of natural physiological functions such as wound healing and tissue regeneration. A particularly attractive aspect of this technology is that diagnostic and therapeutic systems can be combined to produce totally non-invasive, imageguided therapy. This general lecture will review a number of these exciting new applications of ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors as well as the introduction of acoustic hemostasis, especially in organs which are difficult to treat using conventional medical and surgical techniques. (amum lecture)

  13. Accelerate!

    Science.gov (United States)

    Kotter, John P

    2012-11-01

    The old ways of setting and implementing strategy are failing us, writes the author of Leading Change, in part because we can no longer keep up with the pace of change. Organizational leaders are torn between trying to stay ahead of increasingly fierce competition and needing to deliver this year's results. Although traditional hierarchies and managerial processes--the components of a company's "operating system"--can meet the daily demands of running an enterprise, they are rarely equipped to identify important hazards quickly, formulate creative strategic initiatives nimbly, and implement them speedily. The solution Kotter offers is a second system--an agile, networklike structure--that operates in concert with the first to create a dual operating system. In such a system the hierarchy can hand off the pursuit of big strategic initiatives to the strategy network, freeing itself to focus on incremental changes to improve efficiency. The network is populated by employees from all levels of the organization, giving it organizational knowledge, relationships, credibility, and influence. It can Liberate information from silos with ease. It has a dynamic structure free of bureaucratic layers, permitting a level of individualism, creativity, and innovation beyond the reach of any hierarchy. The network's core is a guiding coalition that represents each level and department in the hierarchy, with a broad range of skills. Its drivers are members of a "volunteer army" who are energized by and committed to the coalition's vividly formulated, high-stakes vision and strategy. Kotter has helped eight organizations, public and private, build dual operating systems over the past three years. He predicts that such systems will lead to long-term success in the 21st century--for shareholders, customers, employees, and companies themselves. PMID:23155997

  14. Accelerate!

    Science.gov (United States)

    Kotter, John P

    2012-11-01

    The old ways of setting and implementing strategy are failing us, writes the author of Leading Change, in part because we can no longer keep up with the pace of change. Organizational leaders are torn between trying to stay ahead of increasingly fierce competition and needing to deliver this year's results. Although traditional hierarchies and managerial processes--the components of a company's "operating system"--can meet the daily demands of running an enterprise, they are rarely equipped to identify important hazards quickly, formulate creative strategic initiatives nimbly, and implement them speedily. The solution Kotter offers is a second system--an agile, networklike structure--that operates in concert with the first to create a dual operating system. In such a system the hierarchy can hand off the pursuit of big strategic initiatives to the strategy network, freeing itself to focus on incremental changes to improve efficiency. The network is populated by employees from all levels of the organization, giving it organizational knowledge, relationships, credibility, and influence. It can Liberate information from silos with ease. It has a dynamic structure free of bureaucratic layers, permitting a level of individualism, creativity, and innovation beyond the reach of any hierarchy. The network's core is a guiding coalition that represents each level and department in the hierarchy, with a broad range of skills. Its drivers are members of a "volunteer army" who are energized by and committed to the coalition's vividly formulated, high-stakes vision and strategy. Kotter has helped eight organizations, public and private, build dual operating systems over the past three years. He predicts that such systems will lead to long-term success in the 21st century--for shareholders, customers, employees, and companies themselves.

  15. Obstetrical Ultrasound

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Obstetric Ultrasound Obstetric ultrasound uses sound waves to produce pictures of ... What are the limitations of Obstetrical Ultrasound Imaging? Obstetric ultrasound cannot identify all fetal abnormalities. Consequently, when ...

  16. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... CT scanning , and MRI are the methods of choice in such a setting. Large patients are more ... content. Related Articles and Media Sonohysterography Ultrasound - Abdomen Children's (Pediatric) Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Images ...

  17. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in ... exam may be part of a pelvic ultrasound examination. Doppler ultrasound is a special ultrasound technique that ...

  18. Pondermotive acceleration of electrons to GeV energies by a tightly focused ultra-short ultra-intense laser pulse

    Science.gov (United States)

    Tian, Youwei; Yu, Wei; Lu, Peixiang; He, Feng; Xu, Han

    2005-12-01

    Laser-driven pondermotive acceleration of electrons in vacuum has been considered using computer simulations. It is demonstrated that a low-energy free electron can be violently accelerated to final kinetic energy of GeV by a tightly focused ultra-short ultra-intense laser pulse. Suitable conditions that are crucial for this phenomenon to occur have been investigated. It is shown that selection of appropriate initial conditions like relative time delay between electron and the laser pulse, electron's incident angle and momentum, laser pulse duration and its focal spot size play important roles in the efficient acceleration scheme.

  19. Intravascular Ultrasound

    Science.gov (United States)

    ... Nuclear Ventriculography Optical Coherence Tomography Positron Emission Tomography (PET) Stress Echocardiography Transesophageal Echocardiography Intravascular Ultrasound | Share Intravascular ultrasound ( ...

  20. Evaluation of the therapeutic efficacy of high-intensity focused ultrasound ablation of hepatocellular carcinoma by three-dimensional sonography with a perflubutane-based contrast agent

    Energy Technology Data Exchange (ETDEWEB)

    Numata, Kazushi, E-mail: kz-numa@urahp.yokohama-cu.ac.j [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Fukuda, Hiroyuki; Ohto, Masao; Itou, Ryu [Department of Internal Medicine, Naruto General Hospital, 167 Naruto, Sanbu, Chiba 289-1326 (Japan); Nozaki, Akito; Kondou, Masaaki; Morimoto, Manabu [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan); Karasawa, Eii [Department of Gastroenterology, International University of Health and Welfare Atami Hospital, 13-1 Higashi Kaigan-cho, Atami, Shizuoka 413-0012 (Japan); Tanaka, Katsuaki [Gastroenterological Center, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, Kanagawa 232-0024 (Japan)

    2010-08-15

    Objective: We performed contrast-enhanced three-dimensional sonography (CE 3D US) with a perflubutane-based contrast agent to immediately evaluate the completeness of ablation of small hepatocellular carcinoma (HCC) lesions by extracorporeal high-intensity focused ultrasound (HIFU). Subjects and methods: Twenty-one HCC lesions were treated by a single ultrasound-guided HIFU ablation session, and CE 3D US was performed before, immediately after, and 1 week, and 1 month after HIFU, and contrast-enhanced CT (CE CT) or contrast-enhanced MRI (CE MRI) was performed before HIFU, 1 week and 1 month after HIFU, and during the follow-up period. Results: Immediately and 1 month after HIFU, 17 lesions were evaluated as adequately ablated by CE 3D US, and the other 4 lesions as residual tumors. One month after HIFU, 18 were evaluated as adequately ablated by CE CT or CE MRI, and the other 3 as residual tumors. The evaluation by CE 3D US immediately after HIFU and by CE CT or CE MRI 1 month after HIFU was concordant with 20 lesions. The kappa value for agreement between the findings of CE 3D US and other modalities by two blinded observers was 0.83. When the 1-month CE CT or CE MRI findings were used as the reference standard, the sensitivity, specificity, and accuracy of CE 3D US immediately after HIFU for the diagnosis of the adequate ablation were 100%, 75%, and 95%, respectively. Conclusion: CE 3D US appears to be a useful method for immediate evaluation of therapeutic efficacy of HIFU ablation of HCC lesions.

  1. Resuscitative Long-Bone Sonography for the Clinician: Usefulness and Pitfalls of Focused Clinical Ultrasound to Detect Long-Bone Fractures During Trauma Resuscitation.

    Science.gov (United States)

    Al-Kadi, Azzam S; Gillman, Lawrence M; Ball, Chad G; Panebianco, Nova L; Kirkpatrick, Andrew W

    2009-08-01

    Bone has one of the highest acoustic densities (AD) in the human body. Traditionally, bone has been considered to be a hindrance to the use of ultrasound (US), as US waves are reflected by the dense matrix and obscure underlying structures. The intense wave reflection, however, can clearly illustrate the cortical bony anatomy of long bones, making cortical disruption obvious. Ultrasound can be used at the bedside concurrently with the overall trauma resuscitation, and may potentially limit the patient's and treating team's exposure to ionizing radiation, corroborate clinical findings, and augment procedural success. The extended focused assessment with sonography for trauma (EFAST) is an essential tool in the resuscitation of severe torso trauma, frequently demonstrating intra- pericardial and intra-peritoneal fluid, inferring hemo/pneumothoraces, and demonstrating cardiac function. Although it is typically considered as a diagnosis of exclusion, multiple long-bone fractures may be a source of shock and can be quickly confirmed at the bedside with EFAST. Further, the early detection of long-bone fractures can also aid in the early stabilization of severely injured patients. Sonographic evaluation for long-bone fractures may be particularly useful in austere environments where other imaging modalities are limited, such as in the battlefield, developing world, and space. While prospective study has been limited, selected series have demonstrated high accuracy among both physician and para-medical clinicians in detecting long-bone fractures. Pitfalls in this technique include reduced accuracy with the small bones of the hands and feet, as well as great reliance on user experience. PMID:26815050

  2. Annular and Cylindrical Phased Array Geometries for Transrectal High-Intensity Focused Ultrasound (HIFU) using PZT and Piezocomposite Materials

    Science.gov (United States)

    Seip, Ralf; Chen, Wohsing; Carlson, Roy; Frizzell, Leon; Warren, Gary; Smith, Nadine; Saleh, Khaldon; Gerber, Gene; Shung, Kirk; Guo, Hongkai; Sanghvi, Narendra T.

    2005-03-01

    This paper presents engineering progress and the latest in-vitro and in-vivo results obtained with a 4.0 MHz, 20 element, PZT annular transrectal HIFU array and several 4.0 MHz, 211 element, PZT and piezocomposite cylindrical transrectal HIFU arrays for the treatment of prostate cancer. The geometries of both arrays were designed and analyzed to steer the HIFU beams to the desired sites in the prostate volume using multi-channel electronic drivers, with the intent to increase treatment efficiency and reliability for the next generation of HIFU systems. The annular array is able to focus in depth from 25 mm to 50 mm, generate total acoustic powers in excess of 60W, and has been integrated into a modified Sonablate®500 HIFU system capable of controlling such an applicator through custom treatment planning and execution software. Both PZT- and piezocomposite cylindrical arrays were constructed and their characteristics were compared for the transrectal applications. These arrays have been installed into appropriate transducer housings, and have undergone characterization tests to determine their total acoustic power output, focusing range (in depth and laterally), focus quality, efficiency, and comparison tests to determine the material and technology of choice (PZT or piezocomposite) for intra-cavity HIFU applications. Array descriptions, characterization results, in-vitro and in-vivo results, and an overview of their intended use through the application software is shown.

  3. Simulation study of the effects of near- and far-field heating during focused ultrasound uterine fibroid ablation using an electronically focused phased array: A theoretical analysis of patient safety

    Energy Technology Data Exchange (ETDEWEB)

    Ellens, Nicholas, E-mail: nicholas.ellens@utoronto.ca; Hynynen, Kullervo [Sunnybrook Research Institute, Toronto, Ontario M4N 3M5, Canada and Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7 (Canada)

    2014-07-15

    Purpose: Assess the feasibility of using large-aperture, flat ultrasonic transducer arrays with 6500 small elements operating at 500 kHz without the use of any mechanical components for the thermal coagulation of uterine fibroids. This study examines the benefits and detriments of using a frequency that is significantly lower than that used in clinical systems (1–1.5 MHz). Methods: Ultrasound simulations were performed using the anatomies of five fibroid patients derived from 3D MRI. Using electronic steering solely, the ultrasound focus from a flat, 6500-element phased array was translated around the volume of the fibroids in various patterns to assess the feasibility of completing full treatments from fixed physical locations. Successive temperature maps were generated by numerically solving the bioheat equation. Using a thermal dose model, the bioeffects of these simulations were quantified and analyzed. Results: The simulations indicate that such an array could be used to perform fibroid treatments to 18 EM{sub 43} at an average rate of 90 ± 20 cm{sup 3}/h without physically moving the transducer array. On average, the maximum near-field thermal dose for each patient was below 4 EM{sub 43}. Fibroid tissue could be treated as close as 40 mm to the spine without reaching temperatures expected to cause pain or damage. Conclusions: Fibroids were successfully targeted and treated from a single transducer position to acceptable extents and without causing damage in the near- or far-field. Compared to clinical systems, treatment rates were good. The proposed treatment paradigm is a promising alternative to existing systems and warrants further investigation.

  4. Developing an emergency ultrasound app

    DEFF Research Database (Denmark)

    Foss, Kim Thestrup; Subhi, Yousif; Aagaard, Rasmus;

    2015-01-01

    Focused emergency ultrasound is rapidly evolving as a clinical skill for bedside examination by physicians at all levels of education. Ultrasound is highly operator-dependent and relevant training is essential to ensure appropriate use. When supplementing hands-on focused ultrasound courses, e......-learning can increase the learning effect. We developed an emergency ultrasound app to enable onsite e-learning for trainees. In this paper, we share our experiences in the development of this app and present the final product....

  5. The impact of standing wave effects on transcranial focused ultrasound disruption of the blood-brain barrier in a rat model

    International Nuclear Information System (INIS)

    Microbubble-mediated disruption of the blood-brain barrier (BBB) for targeted drug delivery using focused ultrasound shows great potential as a therapy for a wide range of brain disorders. This technique is currently at the pre-clinical stage and important work is being conducted in animal models. Measurements of standing waves in ex vivo rat skulls were conducted using an optical hydrophone and a geometry dependence was identified. Standing waves could not be eliminated through the use of swept frequencies, which have been suggested to eliminate standing waves. Definitive standing wave patterns were detected in over 25% of animals used in a single study. Standing waves were successfully eliminated using a wideband composite sharply focused transducer and a reduced duty cycle. The modified pulse parameters were used in vivo to disrupt the BBB in a rat indicating that, unlike some other bioeffects, BBB disruption is not dependent on standing wave conditions. Due to the high variability of standing waves and the inability to correctly estimate in situ pressures given standing wave conditions, attempts to minimize standing waves should be made in all future work in this field to ensure that results are clinically translatable.

  6. 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

  7. Calculational parameters of the accelerating-focusing channel of the HF injector for the linear accelerator of the AN USSR IYaI meson factory

    International Nuclear Information System (INIS)

    The results of investigation of RF i.njector (RFI) for the meson factory linac are presented. Investigated are the conditions providing effective bunching of particles, their capture into the acceleration mode, possibilities of change of the bunch output parameters at the expense of the choice of parameters of the accelerating structure and the analysis of electric fields in the four-wire line with electrodes. The main parameters of the RFI are as follows: average radius of the channel 6.23 mm, electric potential on the electrodes 121.9 kV, modu. lation coefficient 1.04-1.69, acceleration efficiency 0.0122- 0.428, the number of bunching periods 14, length 1.3 m. The parameters of the beam have been investigated at current pulse of 50 and 100 μA. The beam current equals 44 mA within the range of the required normalized emittance of 0.15π cmxmrad at the RFI output at beam current of 50 μA; at beam current of 100 μA the part of accelerated particles constituted 75 μA

  8. Combined application of low-intensity pulsed ultrasound and functional electrical stimulation accelerates bone-tendon junction healing in a rabbit model.

    Science.gov (United States)

    Hu, Jianzhong; Qu, Jin; Xu, Daqi; Zhang, Tao; Qin, Ling; Lu, Hongbin

    2014-02-01

    The objective of this study was to elucidate the combined use of low-intensity pulsed ultrasound (LIPUS) and functional electrical stimulation (FES) on patella-patellar tendon (PPT) junction healing using a partial patellectomy model in rabbits. LIPUS was delivered continuously starting day 3 postoperative until week 6. FES was applied on quadriceps muscles to induce tensile force to the repaired PPT junction 5 days per week for 6 weeks since week 7 postoperatively. Forty rabbits with partial patellectomy were randomly divided into four groups: control, LIPUS alone, FES alone, and LIPUS + FES groups. At week 12, the PPT complexes were harvested for histology, radiographs, peripheral quantitative computed tomography, and biomechanical testing. There was better remodeling of newly formed bone and fibrocartilage zone in the three treatment groups compared with the control group. LIPUS and/or FES treatments significantly increased the area and bone mineral content of new bone. The failure load and ultimate strength of PPT complex were also highly improved in the three treatment groups. More new bone formed and higher tensile properties were showed in the LIPUS + FES group compared with the LIPUS or FES alone groups. Early LIPUS treatment and later FES treatment showed the additive effects of accelerating PPT junction healing.

  9. The role of acoustic nonlinearity in tissue heating behind a rib cage using a high-intensity focused ultrasound phased array

    Science.gov (United States)

    Yuldashev, Petr V.; Shmeleva, Svetlana M.; Ilyin, Sergey A.; Sapozhnikov, Oleg A.; Gavrilov, Leonid R.; Khokhlova, Vera A.

    2013-04-01

    The goal of this study was to investigate theoretically the effects of nonlinear propagation in a high-intensity focused ultrasound (HIFU) field produced by a therapeutic phased array and the resultant heating of tissue behind a rib cage. Three configurations of focusing were simulated: in water, in water with ribs in the beam path and in water with ribs backed by a layer of soft tissue. The Westervelt equation was used to model the nonlinear HIFU field, and a 1 MHz phased array consisting of 254 circular elements was used as a boundary condition to the model. The temperature rise in tissue was modelled using the bioheat equation, and thermally necrosed volumes were calculated using the thermal dose formulation. The shapes of lesions predicted by the modelling were compared with those previously obtained in in vitro experiments at low-power sonications. Intensity levels at the face of the array elements that corresponded to the formation of high-amplitude shock fronts in the focal region were determined as 10 W cm-2 in the free field in water and 40 W cm-2 in the presence of ribs. It was shown that exposures with shocks provided a substantial increase in tissue heating, and its better spatial localization in the main focal region only. The relative effects of overheating ribs and splitting of the focus due to the periodic structure of the ribs were therefore reduced. These results suggest that utilizing nonlinear propagation and shock formation effects can be beneficial for inducing confined HIFU lesions when irradiating through obstructions such as ribs. Design of compact therapeutic arrays to provide maximum power outputs with lower intensity levels at the elements is necessary to achieve shock wave regimes for clinically relevant sonication depths in tissue.

  10. Targeted microbubbles destruction with low intensity focused ultrasound%低强度聚焦超声靶向爆破微泡

    Institute of Scientific and Technical Information of China (English)

    董桂芳; 冉海涛; 王志刚; 宫玉萍; 王希

    2013-01-01

    目的 探讨自制低强度聚焦超声(LIFU)体外靶向爆破微泡范围、空间分布,及在兔肝脏组织中应用LIFU辐照载紫杉醇脂质微泡(PLM)的定位控释情况.方法 ①采用4种不同声强(0.3、0.6、0.9、1.2 W/cm-2)LIFU(频率1 MHz,焦距160mm,占空比50%)分别辐照含脂质微泡的水囊,同时从不同切面观察并记录水囊内微泡爆破范围及空间分布形态;②选取新西兰大白兔10只,随机平均分为聚焦超声组(A组)和非聚焦超声组(B组);对实验兔静脉注射PLM后,对A、B组分别采用LIFU和非聚焦超声定位辐照肝脏2 min;辐照后1h处死实验兔,取焦域中心及距离中心1 cm、2cm、3cm处的肝脏组织,采用反相高效液相色谱法测定各肝脏组织内的紫杉醇含量.结果 ①LIFU体外定位爆破微泡范围局限、形状规则,爆破范围随声强增高而增大;②A组辐照中心处紫杉醇浓度最大,距离中心处越远,紫杉醇浓度越低(F=201.81,P<0.05);B组中各位置紫杉醇浓度的差异无统计学意义(F=1.36,P>0.05);辐照中心处,A组紫杉醇浓度高于B组(t=5.28,P<0.05).结论 LIFU能够实现体内外靶向爆破微泡,其聚焦部位和微泡爆破范围可调.%Objective To explore the destruction range and space distribution of microbubbles using low power focused ultrasound (LIFU), and to observe the targeted destruction using paclitaxelcarrying liposome microbubbles (PLM) and LIFU in the liver of rabbits. Methods ①The bladder containing lipid microbubbles was irradiated with 4 different intensities of LIFU (0. 3, 0. 6, 0. 9, 1. 2 W/cmz), and the destruction ranges and spatial distribution shapes of the microbubbles in the bladder were observed and recorded from different facets. ②Ten rabbits were randomly divided into focused ultrasound group (group A, n = 5) and focused ultrasound group (group B, n = 5). After injection of PLM, rabbits in group A and B were irradiated respectively with LIFU and non-focused

  11. A stand for simulation and test of the magnetic components of the focus beam and transport systems for accelerator LUE-200, installation IREN

    International Nuclear Information System (INIS)

    Technical parameters and physical abilities of the equipment stand for simulation and testing of the dipole electromagnet to focus and transport the beam of the linear accelerator (LUE-200) are described. The overall design of the stand, a description of the magnetometer and the positioning system of Hall sensors are presented. The software of the stand has been developed

  12. MR thermometry analysis program for laser- or high-intensity focused ultrasound (HIFU)-induced heating at a clinical MR scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ju; Jeong, Ki Young; Oh, Seung Jae; Park, Eun Hae; Lee, Young Han; Suh, Jin Suck [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Dae Hong [National Cancer Center, Goyang (Korea, Republic of)

    2014-12-15

    Magnetic resonance (MR) thermometry is a noninvasive method for monitoring local temperature change during thermal therapy. In this study, a MR temperature analysis program was established for a laser with gold nanorods (GNRs) and high-intensity focused ultrasound (HIFU)-induced heating MR thermometry. The MR temperature map was reconstructed using the water proton resonance frequency (PRF) method. The temperature-sensitive phase difference was acquired by using complex number subtraction instead of direct phase subtraction in order to avoid another phase unwrapping process. A temperature map-analyzing program was developed and implemented in IDL (Interactive Data Language) for effective temperature monitoring. This one program was applied to two different heating devices at a clinical MR scanner. All images were acquired with the fast spoiled gradient echo (fSPGR) pulse sequence on a 3.0 T GE Discovery MR750 scanner with an 8-channel knee array coil or with a home-built small surface coil. The analyzed temperature values were confirmed by using values simultaneously measured with an optical temperature probe (R{sup 2} = 0.996). The temperature change in small samples induced by a laser or by HIFU was analyzed by using a raw data, that consisted of complex numbers. This study shows that our MR thermometry analysis program can be used for thermal therapy study with a laser or HIFU at a clinical MR scanner. It can also be applied to temperature monitoring for any other thermal therapy based on the PRF method.

  13. 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.

  14. 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.)

  15. Localized Down-regulation of P-glycoprotein by Focused Ultrasound and Microbubbles induced Blood-Brain Barrier Disruption in Rat Brain

    Science.gov (United States)

    Cho, Hongseok; Lee, Hwa-Youn; Han, Mun; Choi, Jong-Ryul; Ahn, Sanghyun; Lee, Taekwan; Chang, Yongmin; Park, Juyoung

    2016-08-01

    Multi-drug resistant efflux transporters found in Blood-Brain Barrier (BBB) acts as a functional barrier, by pumping out most of the drugs into the blood. Previous studies showed focused ultrasound (FUS) induced microbubble oscillation can disrupt the BBB by loosening the tight junctions in the brain endothelial cells; however, no study was performed to investigate its impact on the functional barrier of the BBB. In this study, the BBB in rat brains were disrupted using the MRI guided FUS and microbubbles. The immunofluorescence study evaluated the expression of the P-glycoprotein (P-gp), the most dominant multi-drug resistant protein found in the BBB. Intensity of the P-gp expression at the BBB disruption (BBBD) regions was significantly reduced (63.2 ± 18.4%) compared to the control area. The magnitude of the BBBD and the level of the P-gp down-regulation were significantly correlated. Both the immunofluorescence and histologic analysis at the BBBD regions revealed no apparent damage in the brain endothelial cells. The results demonstrate that the FUS and microbubbles can induce a localized down-regulation of P-gp expression in rat brain. The study suggests a clinically translation of this method to treat neural diseases through targeted delivery of the wide ranges of brain disorder related drugs.

  16. 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.)

  17. 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.

  18. Pharmacokinetic analysis of 111 in-labeled liposomal Doxorubicin in murine glioblastoma after blood-brain barrier disruption by focused ultrasound.

    Directory of Open Access Journals (Sweden)

    Feng-Yi Yang

    Full Text Available The goal of this study was to evaluate the pharmacokinetics of targeted and untargeted (111In-doxorubicin liposomes after these have been intravenously administrated to tumor-bearing mice in the presence of blood-brain barrier disruption (BBB-D induced by focused ultrasound (FUS. An intracranial brain tumor model in NOD-scid mice using human brain glioblastoma multiforme (GBM 8401 cells was developed in this study. (111In-labeled human atherosclerotic plaque-specific peptide-1 (AP-1-conjugated liposomes containing doxorubicin (Lipo-Dox; AP-1 Lipo-Dox were used as a microSPECT probe for radioactivity measurements in the GBM-bearing mice. Compared to the control tumors treated with an injection of (111In-AP-1 Lipo-Dox or (111In-Lipo-Dox, the animals receiving the drugs followed by FUS exhibited enhanced accumulation of the drug in the brain tumors (p<0.05. Combining sonication with drugs significantly increased the tumor-to-normal brain doxorubicin ratio of the target tumors compared to the control tumors. The tumor-to-normal brain ratio was highest after the injection of (111In-AP-1 Lipo-Dox with sonication. The (111In-liposomes micro-SPECT/CT should be able to provide important information about the optimum therapeutic window for the chemotherapy of brain tumors using sonication.

  19. Intense focused ultrasound can reliably induce sensations in human test subjects in a manner correlated with the density of their mechanoreceptors.

    Science.gov (United States)

    Dickey, Trevor C; Tych, Rowen; Kliot, Michel; Loeser, John D; Pederson, Kristin; Mourad, Pierre D

    2012-01-01

    Sensations generated by intense focused ultrasound (iFU) can occur cutaneously and/or at depth, in contrast to other forms of stimulation (e.g., heat, electricity), whose action usually occurs only at the skin surface, or mechanical stimulation (e.g., von Frey hairs, calibrated forceps, tourniquets) that compress and thus stimulate all tissue. Previous work on iFU stimulation has led to the hypothesis that the tactile basis of iFU stimulation should correlate with the density of mechanoreceptors at the site of iFU stimulation. Here we tested that hypothesis, correlating a "two-point" neurological examination-a standard measure of superficial mechanoreceptor density-with the intensity of superficially applied iFU necessary to generate sensations with high sensitivity and specificity. We applied iFU at 1.1 MHz for 0.1 s to the fingertip pads of 17 test subjects in a blinded fashion and escalated intensities until they consistently observed iFU-induced sensations. Most test subjects achieved high values of sensitivity and specificity, doing so at values of spatially and temporally averaged intensity measuring mechanoreceptors as determined by a standard two-point discrimination neurological examination, consistent with earlier hypotheses.

  20. HIGH-INTENSITY FOCUSED ULTRASOUND FOR TREATMENT OF UNRESECTABLE TUMORS LOCATED IN THE WALLS OF CHEST AND ABDOMEN IN 10 PATIENTS

    Institute of Scientific and Technical Information of China (English)

    郑国强; 郭峰; 霍苓; 李正

    2003-01-01

    Objective: To present our results of high-intensity focused ultrasound (HIFU) treatment in 10 patients with unresectable tumors involved in the walls of chest and abdomen. Methods: Tumors located in the walls of the chest and abdomen in 10 patients were treated by HIFU, including local recurrence of fibrosarcoma in 1 case and local invasion or metastases in 9 cases. All of the 10 patients had received anti-cancer treatments before HIFU, 3 patients were complicated with intercostal neuralgia. Results: Partial responses were obtained in 2 patients, minor response in 1 patient, stable disease in 4, progressive disease in 2 after HIFU treatments. All the intercostal neuralgia in 3 patients was disappeared after HIFU. Bone scan showed that site of rib metastasis before HIFU became normal after HIFU in one patient. Conclusion: Our preliminary results showed that HIFU could get good results for patients with malignant tumors located in the walls of chest and abdomen if they are focal tumors, even if they are complicated with rib metastasis.

  1. Elucidation of the role of biological factors and device design in cerebral NIRS using an in vivo hematoma model based on high-intensity focused ultrasound

    Science.gov (United States)

    Wang, Jianting; Huang, Stanley; Myers, Matthew; Chen, Yu; Welle, Cristin; Pfefer, Joshua

    2016-03-01

    Near-Infrared Spectroscopy (NIRS) is an emerging medical countermeasure for rapid, field detection of hematomas caused by traumatic brain injury (TBI). Bench and animal tests to determine NIRS sensitivity and specificity are needed. However, current animal models involving non-invasively induced, localized neural damage are limited. We investigated an in vivo murine hematoma model in which cerebral hemorrhage was induced noninvasively by high-intensity focused ultrasound (HIFU) with calibrated positioning and parameters. To characterize the morphology of induced hematomas, we used skull-intact histological evaluation. A multi-wavelength fiber-optic NIRS system with three source-detector separation distances was used to detect hematoma A 1.1 MHz transducer produced consistent small-to-medium hematoma localized to a single hemisphere, along with bruising of the scalp, with a low mortality rate. A 220 kHz transducer produced larger, more diffuse hematomas, with higher variability in size and a correspondingly higher mortality rate. No skin bruising or blood accumulation between the skin and skull was observed following injury application with the 220 kHz transducer. Histological analysis showed higher sensitivity for larger hematomas (>4x4 mm2). NIRS optical density change after HIFU was able to detect all hematomas, with sensitivity dependent on wavelength and separation distance. While improvements in methods for validating cerebral blood distribution are needed, the HIFU hematoma model provided useful insights that will inform development of biologically relevant, performance test methods for cerebral NIRS systems.

  2. Acoustic Cavitation Enhances Focused Ultrasound Ablation with Phase-Shift Inorganic Perfluorohexane Nanoemulsions: An In Vitro Study Using a Clinical Device.

    Science.gov (United States)

    Zhao, Lu-Yan; Zou, Jian-Zhong; Chen, Zong-Gui; Liu, Shan; Jiao, Jiao; Wu, Feng

    2016-01-01

    Purpose. To investigate whether acoustic cavitation could increase the evaporation of a phase-shift inorganic perfluorohexane (PFH) nanoemulsion and enhance high intensity focused ultrasound (HIFU) ablation. Materials and Methods. PFH was encapsulated by mesoporous silica nanocapsule (MSNC) to form a nanometer-sized droplet (MSNC-PFH). It was added to a tissue-mimicking phantom, whereas phosphate buffered saline (PBS) was added as a control (PBS-control). HIFU (P ac = 150 W, t = 5/10 s) exposures were performed in both phantoms with various duty cycles (DC). US images, temperature, and cavitation emissions were recorded during HIFU exposure. HIFU-induced lesions were measured and calculated. Results. Compared to PBS-control, MSNC-PFH nanoemulsion could significantly increase the volume of HIFU-induced lesion (P cavitation was much stronger in the pulsed-HIFU than that in the continuous-wave HIFU exposure. Compared to 100%-DC exposure, the mean volume of lesion induced by 5 s exposure at 10%-DC was significantly larger, but smaller at 2%-DC. Conclusions. MSNC-PFH nanoemulsion can significantly enhance HIFU ablation. Appropriate pulsed-HIFU exposure could significantly increase the volume of lesion and reduce total US energy required for HIFU ablation. PMID:27419138

  3. 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)

    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.)

  4. Antibodies targeted to the brain with image-guided focused ultrasound reduces amyloid-beta plaque load in the TgCRND8 mouse model of Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Jessica F Jordão

    Full Text Available Immunotherapy for Alzheimer's disease (AD relies on antibodies directed against toxic amyloid-beta peptide (Abeta, which circulate in the bloodstream and remove Abeta from the brain. In mouse models of AD, the administration of anti-Abeta antibodies directly into the brain, in comparison to the bloodstream, was shown to be more efficient at reducing Abeta plaque pathology. Therefore, delivering anti-Abeta antibodies to the brain of AD patients may also improve treatment efficiency. Transcranial focused ultrasound (FUS is known to transiently-enhance the permeability of the blood-brain barrier (BBB, allowing intravenously administered therapeutics to enter the brain. Our goal was to establish that anti-Abeta antibodies delivered to the brain using magnetic resonance imaging-guided FUS (MRIgFUS can reduce plaque pathology. To test this, TgCRND8 mice received intravenous injections of MRI and FUS contrast agents, as well as anti-Abeta antibody, BAM-10. MRIgFUS was then applied transcranially. Within minutes, the MRI contrast agent entered the brain, and BAM-10 was later found bound to Abeta plaques in targeted cortical areas. Four days post-treatment, Abeta pathology was significantly reduced in TgCRND8 mice. In conclusion, this is the first report to demonstrate that MRIgFUS delivery of anti-Abeta antibodies provides the combined advantages of using a low dose of antibody and rapidly reducing plaque pathology.

  5. [Diagnosis and treatment of local recurrence of prostate cancer using hystoscanning and high-intensity focused ultrasound in patients after radical prostatectomy].

    Science.gov (United States)

    Glybochko, P V; Aliaev, Iu G; Krupinov, G E; Rapoport, L M; Amosov, A V; Bezrukov, E A; Novichkov, N D; Lachinov, É L; Ganzha, T M; Obukhov, A A; Lerner, Iu V

    2014-01-01

    The study was aimed to the improvement of the diagnosis and treatment of patients with prostate cancer (PC). The study included 46 patients with recurrent prostate cancer after radical prostatectomy (RPE). The examination included contrast enhanced magnetic resonance imaging (endorectal coil 1.5T) and hystoscanning. All patients had local recurrence confirmed by the morphologically results of transrectal biopsy of the area of vesicourethral anastomosis. All patients underwent high-intensity focused ultrasound (HIFU). Before RPE, protate volume ranged from 21 to 102 cm3. The median age was 62 (46-68) years. PSA levels before a HIFU session ranged from 0.4 to 18 ng/ml. Nadir PSA level after 3 months of follow up was 0.1 ng/ml. Five-year disease-free survival in patients with locally recurrent prostate cancer after HIFU in the group of low cancer risk was 10 (81%), moderate risk--18 (57%), high risk--12 (42%). Contrast enhanced magnetic resonance imaging and hystoscanning are highly informative methods for diagnosis of local recurrence after radical prostatectomy, and HIFU can be categorized as highly effective treatment. PMID:25807764

  6. High-intensity focused ultrasound (HIFU) using Sonablate{trade mark, serif} devices for the treatment of localized prostate cancer: 13-year experience

    Science.gov (United States)

    Uchida, Toyoaki; Tomonaga, Tetsuro; Shoji, Sunao; Kim, Hakushi; Nagata, Yoshihiro

    2012-11-01

    To report on the long-term results of high-intensity focused ultrasound (HIFU) in the treatment of localized prostate cancer. Eight hundred and eighty-four men with prostate cancer treated with Sonablate® (SB) devices were included. All patients were followed for more than 2 years. The patients were divided into three groups: in the first group, 419 patients were treated with SB200/500 from 1999 to 2006; in the second group, 263 patients were treated with SB 500 ver. 4 from 2005 to 2009: in the third group, 202 patients were treated with SB 500 TCM from 2007 up to present. Biochemical failure was defined according to the Phoenix definition (PSA nadir + 2 ng/ml). The mean age, PSA, Gleason score, operation time, and follow-up period in each group were 68, 66 and 67 years, 11.2, 9.7 and 9.3 ng/ml, 6.2, 6.6 and 6.7, 167, 101 and 106 min, and 56, 48 and 36 months, respectively. The biochemical disease-free rate (bDFR) in each group at 5 years was, respectively, 54%, 61% and 84%, and was 50% at 10 years in the SB200/500 group (pcultural and economic vectors have caused a shift from to minimally invasive techniques.

  7. Localized Down-regulation of P-glycoprotein by Focused Ultrasound and Microbubbles induced Blood-Brain Barrier Disruption in Rat Brain

    Science.gov (United States)

    Cho, HongSeok; Lee, Hwa-Youn; Han, Mun; Choi, Jong-ryul; Ahn, Sanghyun; Lee, Taekwan; Chang, Yongmin; Park, Juyoung

    2016-01-01

    Multi-drug resistant efflux transporters found in Blood-Brain Barrier (BBB) acts as a functional barrier, by pumping out most of the drugs into the blood. Previous studies showed focused ultrasound (FUS) induced microbubble oscillation can disrupt the BBB by loosening the tight junctions in the brain endothelial cells; however, no study was performed to investigate its impact on the functional barrier of the BBB. In this study, the BBB in rat brains were disrupted using the MRI guided FUS and microbubbles. The immunofluorescence study evaluated the expression of the P-glycoprotein (P-gp), the most dominant multi-drug resistant protein found in the BBB. Intensity of the P-gp expression at the BBB disruption (BBBD) regions was significantly reduced (63.2 ± 18.4%) compared to the control area. The magnitude of the BBBD and the level of the P-gp down-regulation were significantly correlated. Both the immunofluorescence and histologic analysis at the BBBD regions revealed no apparent damage in the brain endothelial cells. The results demonstrate that the FUS and microbubbles can induce a localized down-regulation of P-gp expression in rat brain. The study suggests a clinically translation of this method to treat neural diseases through targeted delivery of the wide ranges of brain disorder related drugs. PMID:27510760

  8. 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)

    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.)

  9. Development of a focused ultrasound-assisted extraction method for the determination of trace concentrations of Cr and Mn in pharmaceutical formulations by ETAAS.

    Science.gov (United States)

    de Paula, Carlos Eduardo R; Caldas, Luiz Fernando S; Brum, Daniel M; Cassella, Ricardo J

    2013-02-23

    This paper reports the development of a new method for the focused ultrasound extraction of Cr and Mn from pharmaceutical formulations and their determination by electrothermal atomic absorption spectrometry (ETAAS). The method was optimized by evaluating the influence of several variables such as the sonication power and time, concentration of HCl in the extractant solution and mass of sample employed in the extraction procedure. The curves of pyrolysis and atomization were constructed for both analytes in order to evaluate the effect of the matrix on the measurement of Cr and Mn. Quantitative extraction of both Cr and Mn was achieved when 25-150 mg of the sample were sonicated for 30 min at 50% power with 5 ml of a 1 moll(-1) HCl solution. The developed method was successfully applied in the determination of Cr and Mn in samples of pharmaceutical formulations containing different active principles such as ciprofloxacin, cephalexin, azithromycin, amlodipine and methionine. There was no statistical (95% confidence level, paired t-test) difference between the results obtained by the proposed method and the results obtained after total digestion of the samples. PMID:23245262

  10. Spatiotemporal control of gene expression in bone-marrow derived cells of the tumor microenvironment induced by MRI guided focused ultrasound.

    Science.gov (United States)

    Fortin, Pierre-Yves; Lepetit-Coiffé, Matthieu; Genevois, Coralie; Debeissat, Christelle; Quesson, Bruno; Moonen, Chrit T W; Konsman, Jan Pieter; Couillaud, Franck

    2015-09-15

    The tumor microenvironment is an interesting target for anticancer therapies but modifying this compartment is challenging. Here, we demonstrate the feasibility of a gene therapy strategy that combined targeting to bone marrow-derived tumor microenvironment using genetically modified bone-marrow derived cells and control of transgene expression by local hyperthermia through a thermo-inducible promoter. Chimera were obtained by engraftment of bone marrow from transgenic mice expressing reporter genes under transcriptional control of heat shock promoter and inoculated sub-cutaneously with tumors cells. Heat shocks were applied at the tumor site using a water bath or magnetic resonance guided high intensity focused ultrasound device. Reporter gene expression was followed by bioluminescence and fluorescence imaging and immunohistochemistry. Bone marrow-derived cells expressing reporter genes were identified to be mainly tumor-associated macrophages. We thus provide the proof of concept for a gene therapy strategy that allows for spatiotemporal control of transgenes expression by macrophages targeted to the tumor microenvironment. PMID:26299614

  11. Experimental Observation of Focused Ultrasound Ablation of Tonsil in Dogs%高强度聚焦超声消融普通狗扁桃体实验观察

    Institute of Scientific and Technical Information of China (English)

    吴显文; 李东; 王熙; 李莹; 陈文直; 胡国华

    2016-01-01

    Objective To investigate the efficacy and safety of tonsil sonication of ordinary greyhound with focused ultrasound. Material and method Desired focused ultrasound dosage combination were got from ox liver experi-ment in vitro. Bilateral tonsils of four common greyhound were sonicated with the selected dosage combination,the local and systematic symptoms and signs of the greyhound were observed after ultrasound sonication,the length and width before and after sonication were measured,and the histological change under light microscope were recorded. Results The temperatures of animals raised and then dropped to the normal level 3 days after sonication. The tonsil size become smaller to different degree after focused ultrasound sonication by a dose dependent model,with the shrinkage up to 44.5%. There is no infection,hematoma and bleeding in the local mucosal tissue. The food-intake of animal reduced 2 to 3 days after the sonication,but they did not stop eating or refused eating. Their food-intake began to recover to the primary level be-fore sonication 4 days after the sonication. It was found that there is coagulation necrosis region,hemangiectasia and hyperemia under mucosal membrane,while the surface epithelial appeared to be normal in the tonsil 3 days after the irradiation. There was granulation generated under tonsil mucosa and necrotic tissue gradually became fibrosis 7 days after sonication. Conclusion Focused ultrasound could reduce the tonsil size of the common greyhound,and obtain ablation effect by dose dependent model. There was no local bleeding infection and surrounding tissue injury during and post irradiation,and the epithelium of mucosal membrane was intact.

  12. Focus on focusing

    International Nuclear Information System (INIS)

    The discovery and impact of the principle of strong focusing was celebrated at a history Symposium at Stanford on 25 July in the course of the 1985 US Summer School on Particle Accelerators. Burt Richter, Stanford Linac Director, who introduced all the speakers with well chosen reminders about their various contributions related to the theme of the symposium, remarked that it was an appropriate time to be lauding the great contributions of accelerator physicists following the Nobel Prize award to Simon van der Meer for outstanding achievements in accelerator physics

  13. Enhancement in blood-tumor barrier permeability and delivery of liposomal doxorubicin using focused ultrasound and microbubbles: evaluation during tumor progression in a rat glioma model

    Science.gov (United States)

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

    2015-03-01

    Effective drug delivery to brain tumors is often challenging because of the heterogeneous permeability of the ‘blood tumor barrier’ (BTB) along with other factors such as increased interstitial pressure and drug efflux pumps. Focused ultrasound (FUS) combined with microbubbles can enhance the permeability of the BTB in brain tumors, as well as the blood-brain barrier in the surrounding tissue. In this study, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was used to characterize the FUS-induced permeability changes of the BTB in a rat glioma model at different times after implantation. 9L gliosarcoma cells were implanted in both hemispheres in male rats. At day 9, 14, or 17 days after implantation, FUS-induced BTB disruption using 690 kHz ultrasound and definity microbubbles was performed in one tumor in each animal. Before FUS, liposomal doxorubicin was administered at a dose of 5.67 mg kg-1. This chemotherapy agent was previously shown to improve survival in animal glioma models. The transfer coefficient Ktrans describing extravasation of the MRI contrast agent Gd-DTPA was measured via DCE-MRI before and after sonication. We found that tumor doxorubicin concentrations increased monotonically (823  ±  600, 1817  ±  732 and 2432  ±  448 ng g-1) in the control tumors at 9, 14 and 17 d. With FUS-induced BTB disruption, the doxorubicin concentrations were enhanced significantly (P drug delivery are relatively consistent over time, at least in this tumor model. These results are encouraging for the use of large drug carriers, as they suggest that even large/late-stage tumors can benefit from FUS-induced drug enhancement. Corresponding enhancements in Ktrans were found to be variable in large/late-stage tumors and not significantly different than controls, perhaps reflecting the size mismatch between the liposomal drug (~100 nm) and Gd-DTPA (molecular weight: 938 Da; hydrodynamic diameter: ≃2 nm). It may be necessary

  14. High-Intensity Focused Ultrasound for the Treatment of Localized and Locally Advanced Hormone-Resistant Prostate Cancer: 2,5 Year Outcome

    Science.gov (United States)

    Solovov, V. A.; Dvoynikov, S. Y.; Vozdvizhenskiy, M. O.

    2011-09-01

    Introduction & Objectives: High-Intensity Focused Ultrasound (HIFU) has been shown to be a successful treatment for localised prostate cancer (PC). Here we have explored the effectiveness of the HIFU treatment for hormone-resistant prostate cancer (HRPC). Materials & Methods: 341 patients were treated in our center between September 2007 and December 2009; all of them showed treatment failure following hormone ablation. The median time before hormone-resistance was 20 (3-48) months. In the group with localised PC: number of patients 237, Gleason score ≤7, stage T1-2N0M0, age 69 (60-89) years, mean PSA before treatment 40,0 (5,8-92,9) ng/ml, mean prostate volume—39,3 (28-92) cc; in the group with locally advanced PC: number of patients 104, Gleason score ≤9, stage T2-3N0M0, age 72 (52-83) years, PSA before treatment 30,3 (20,1-60) ng/ml, mean prostate volume—41,2 (25-198) cc. HIFU was delivered under spinal anesthesia using the Ablatherm HIFU device (EDAP, France). Pre HIFU transurethral resection of the prostate (TURP) was performed for all patients. Mean follow-up time 18 months (3-30). Results: The median PSA level 12 months after HIFU treatment was 0,04 (0-2,24) ng/ml—localised PC, and for locally advanced disease—0,05 (0-48,4) ng/ml, at 18 months after HIFU treatment this was 0,2 (0,02-2,0) ng/ml for localised PC, and for locally advanced disease 0,18 (0,04-7,45) ng/ml. Patients with localised PC has 4,5% recurrence, those with locally advanced PC 20%. Kaplan-Meir analyses of the total group indicated that the risk of recurrence after 1 year follow-up was 10%, the risk of recurrence was 19% after 2 years of follow-up. Conclusions: Our initial experience shows that ultrasound ablation is safe, minimally invasive and effective as a treatment for localised and locally advanced hormone-resistant prostate cancer.

  15. Medical ultrasound imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2007-01-01

    The paper gives an introduction to current medical ultrasound imaging systems. The basics of anatomic and blood flow imaging are described. The properties of medical ultrasound and its focusing are described, and the various methods for two- and three-dimensional imaging of the human anatomy...... are shown. Both systems using linear and non-linear propagation of ultrasound are described. The blood velocity can also be non-invasively visualized using ultrasound and the basic signal processing for doing this is introduced. Examples for spectral velocity estimation, color flow maging and the new vector...

  16. Preliminary Investigation of Patient Suitability for Ultrasound Guided High Intensity Focused Ultrasound Ablation of Uterine Fibroids%网络来源子宫肌瘤患者超声消融治疗适合程度分析

    Institute of Scientific and Technical Information of China (English)

    陈骊; 邓勇斌; 邹敏; 吴灿; 岳莹; 熊郁

    2012-01-01

    目的 评价子宫肌瘤患者适合超声监控超声消融治疗的程度.方法 回顾性分析从2011年4月至2012年2月通过网络了解超声消融治疗技术并于重庆海扶医院妇科就诊的172例患者.按照中国食品及药物管理局通过的标准进行初步筛选后,再进行机载超声模拟定位、盆腔核磁共振成像(MRI)检查及临床检查以进一步排除不适合超声消融治疗的患者.结果 172例患者中,149例选择超声消融治疗,21例选择手术治疗,2例选择不治疗.149例选择超声消融治疗的患者经机载超声定位及MRI检查后,141 (94.6%)例最终接受了超声消融治疗,共治疗221个肌瘤;其中前位子宫120例,188个肌瘤;后位子宫21例,33个肌瘤.术后1~3 d行MRI检查,显示平均消融率为(78.7±25.8)%.8(5.4%)例患者不适合超声消融治疗,其原因包括:T2高信号1(0.7%)例;肌瘤自发性坏死1(0.7%)例;肠道推挤困难1(0.7%)例;合并卵巢肿瘤需手术1(0.7%)例;肌瘤过小4(2.7%)例.结论 网络来源子宫肌瘤患者接受超声消融治疗的比例较高;在自愿选择超声消融治疗的患者中,绝大多数患者适合超声消融治疗.%Objective To investigate patient suitability for ultrasound guided high intensity focused ultrasound (HIFU) treatment of symptomatic uterine fibroids. Methods A retrospective analysis of 172 patients seeking for minimally invasive treatment of uterine fibroids from internet was performed. The patients were first evaluated following the eligibility criteria from the State Food and Drug Administration of China. Then, the eligible patients underwent simulation, pelvic MRI and clinical examination to determine suitability for the procedure. Results 149 of 172 patients (86. 7%) had ultrasound guided HIFU (USgHIFU) treatment after consulting with gynecologists. Following further ultrasound simulation and MRI examination, 141 (94. 6%) patients were deemed suitable for USg

  17. A Focused Transport Approach to SEP acceleration at a Fast Parallel Shock in the Corona Including Self-excitation of Alfvén Waves

    Science.gov (United States)

    le Roux, J. A.

    2012-12-01

    It has been argued that the acceleration of SEPS at a quasi-parallel CME-driven shock to GeV energies in the corona only occurs if strong wave-excitation by SEPs ahead of the shock reduces the parallel mean free path upstream, thus boosting the rate of diffusive shock acceleration. To investigate this issue, we modeled SEP acceleration at a fast parallel traveling shock in the corona with an existing time-dependent focused transport model. The model has been expanded recently to also feature time-dependent self-excitation and damping of Alfvén waves by SEP anisotropies ahead of the shock based on standard quasi-linear theory. Alfvén wave propagation near the traveling shock is modeled based on standard theory for wave transport in a slowly varying non-uniform plasma medium. Preliminary results will be shown to illustrate the increase in wave power driven by SEP anisotropies upstream, the effect of the shock wave in shortening the wave length and increasing the wave amplitude of Alfvén waves, and the associated acceleration of SEPs by 1st order Fermi acceleration to high energies. The role of the acceleration of the cross-shock solar wind flow, which was found to create a downstream population of shock pre-heated particles which forms an additional source for injection into 1st order Fermi acceleration, will be discussed in terms of how it affects self-excitation of Alfvén waves and the formation of high-energy SEPs by 1st order Fermi acceleration.

  18. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... ultrasound is most often performed to evaluate the: uterus cervix ovaries fallopian tubes bladder Pelvic ultrasound exams ... to view the endometrium , the lining of the uterus, and the ovaries. Transvaginal ultrasound also provides a ...

  19. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... make secure contact with the body and eliminate air pockets between the transducer and the skin that ... Pelvic Ultrasound Imaging? Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal ...

  20. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... Pelvis Ultrasound imaging of the pelvis uses sound waves to produce pictures of the structures and organs ... of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or sonography , ...

  1. Intravascular ultrasound

    Science.gov (United States)

    IVUS; Ultrasound - coronary artery; Endovascular ultrasound; Intravascular echocardiography ... A tiny ultrasound wand is attached to the top of a thin tube. This tube is called a catheter. The catheter ...

  2. Ultrasound -- Pelvis

    Medline Plus

    Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. There are three types of pelvic ultrasound: ...

  3. Targeted delivery of erythropoietin by transcranial focused ultrasound for neuroprotection against ischemia/reperfusion-induced neuronal injury: a long-term and short-term study.

    Directory of Open Access Journals (Sweden)

    Sheng-Kai Wu

    Full Text Available Erythropoietin (EPO is a neuroprotective agent against cerebral ischemia/reperfusion (I/R-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS sonication with microbubbles (MBs can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection.

  4. Pharmacodynamic and therapeutic investigation of focused ultrasound-induced blood-brain barrier opening for enhanced temozolomide delivery in glioma treatment.

    Directory of Open Access Journals (Sweden)

    Hao-Li Liu

    Full Text Available Focused ultrasound (FUS exposure with the presence of microbubbles has been shown to transiently open the blood-brain barrier (BBB, and thus has potential to enhance the delivery of various kinds of therapeutic agents into brain tumors. The purpose of this study was to assess the preclinical therapeutic efficacy of FUS-BBB opening for enhanced temozolomide (TMZ delivery in glioma treatment. FUS exposure with microbubbles was delivered to open the BBB of nude mice that were either normal or implanted with U87 human glioma cells. Different TMZ dose regimens were tested, ranging from 2.5 to 25 mg/kg. Plasma and brain samples were obtained at different time-points ranging from 0.5 to 4 hours, and the TMZ concentration within samples was quantitated via a developed LC-MS/MS procedure. Tumor progression was followed with T2-MRI, and animal survival and brain tissue histology were conducted. Results demonstrated that FUS-BBB opening caused the local TMZ accumulation in the brain to increase from 6.98 to 19 ng/mg. TMZ degradation time in the tumor core was found to increase from 1.02 to 1.56 hours. Improved tumor progression and animal survival were found at different TMZ doses (up to 15% and 30%, respectively. In conclusion, this study provides preclinical evidence that FUS-BBB opening increases the local concentration of TMZ to improve the control of tumor progression and animal survival, suggesting the potential for clinical application to improve current brain tumor treatment.

  5. 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.

  6. Determination of endocrine disrupting compounds in fish liver, brain, and muscle using focused ultrasound solid-liquid extraction and dispersive solid phase extraction as clean-up strategy.

    Science.gov (United States)

    Ros, Oihana; Vallejo, Asier; Olivares, Maitane; Etxebarria, Nestor; Prieto, Ailette

    2016-08-01

    This study describes a new method for the simultaneous extraction of several endocrine disrupting compounds, including alkylphenols (APs), estrogen, bisphenol-A (BPA) and one phthalate metabolite (mono-2-ethylhexyl ester, MEHP) in fish liver, brain, and muscle. Parameters affecting the extraction (extraction solvent and temperature) and the clean-up (dispersive phase nature and amount) steps were evaluated. The extraction was performed by means of focused ultrasound solid-liquid extraction (FUSLE) using 10 mL of n-hexane:acetone (50:50, v/v) for 5 min at ~0 °C, and the clean-up was done by means of dispersive solid phase extraction (dSPE) using 100 mg of ENVI-CARB and 100 mg of MgSO4 for the cleaning of brain and muscle extracts together with 100 mg of PSA in the case of liver extracts. Good apparent recoveries were obtained in the case of liver (62-132 %), brain (66-120 %), and muscle (74-129 %), relative standard deviation (RSD%) was always below 26 %, and the method detection limits (MDLs) were at low ng/g level. The developed method was applied to fish captured in Urdaibai estuary (Bay of Biscay) in December 2015, and the concentrations obtained were in the range MDL-1115 ng/g in brain, MDL-962 ng/g in muscle, and MDL-672 ng/g in liver. In general, the highest concentrations were measured in liver, followed by brain and muscle. In addition, diethylstilbestrol was only detected in fish brain. Graphical Abstract MS method scheme for the/MS method scheme for the determination of EDCs in fish liver, brain and muscle. PMID:27342793

  7. Focal therapy with high-intensity focused ultrasound for prostate cancer in the elderly: a feasibility study with 10 years follow-up

    Directory of Open Access Journals (Sweden)

    Amine B. El Fegoun

    2011-04-01

    Full Text Available PURPOSE: To evaluate the long-term efficacy of prostate cancer control and complication rates, in the elderly, after focal therapy with high-intensity focused ultrasound (HIFU. MATERIALS AND METHODS: Between June 1997 and March 2000, patients with localized prostate cancer were included into a focal therapy protocol. Inclusion criteria were: PSA < 10 ng/mL, < 3 positive biopsies with only 1 lobe involved, clinical stage < T2a, Gleason score < 7 (3+4, negative CT scan and bone scan. Hemi-ablation of the prostate was performed with the Ablatherm(R device. Survival, complication rates and urinary continence were evaluated. Control biopsies were performed at 1 year. Treatment failure was defined as a positive biopsy or need for salvage therapy. RESULTS: Twelve patients with a mean age 70 years were included. Median follow-up was 10 years. Control prostate biopsies were negative in 11/12 (91% patients. Overall survival was 83% (10/12 and cancer specific survival was 100% at 10 years. Two patients died from other causes. Recurrence free survival was 90% (95% CI; 0.71-1 at 5 years, and 38% (95% CI; 0.04-0.73 at 10 years. Five patients had salvage therapy with repeat HIFU (n = 1 or hormonal therapy (n = 4 and all salvage patients were alive at 10 years. No patients developed lymph node or bone metastasis. No patients suffered from urinary incontinence. International Prostate Symptom Score was stable at 1 year. Complications included two urinary tract infections and one episode of acute urinary retention. CONCLUSIONS: Hemi-prostate ablation with HIFU can be safely performed in selected elderly patients with adequate long-term cancer control and low complication rates. Results from larger prospective studies using improved imaging techniques and extensive biopsy protocols are awaited.

  8. Magnetic Resonance Imaging-Guided High-Intensity Focused Ultrasound Ablation of Uterine Fibroids: Effect of Bowel Interposition on Procedure Feasibility and a Unique Bowel Displacement Technique.

    Directory of Open Access Journals (Sweden)

    Young-Sun Kim

    Full Text Available To evaluate the effect of bowel interposition on assessing procedure feasibility, and the usefulness and limiting conditions of bowel displacement techniques in magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU ablation of uterine fibroids.Institutional review board approved this study. A total of 375 screening MR exams and 206 MR-HIFU ablations for symptomatic uterine fibroids performed between August 2010 and March 2015 were retrospectively analyzed. The effect of bowel interposition on procedure feasibility was assessed by comparing pass rates in periods before and after adopting a unique bowel displacement technique (bladder filling, rectal filling and subsequent bladder emptying; BRB maneuver. Risk factors for BRB failure were evaluated using logistic regression analysis.Overall pass rates of pre- and post-BRB periods were 59.0% (98/166 and 71.7% (150/209, and in bowel-interposed cases they were 14.6% (7/48 and 76.4% (55/72, respectively. BRB maneuver was technically successful in 81.7% (49/60. Through-the-bladder sonication was effective in eight of eleven BRB failure cases, thus MR-HIFU could be initiated in 95.0% (57/60. A small uterus on treatment day was the only significant risk factor for BRB failure (B = 0.111, P = 0.017.The BRB maneuver greatly reduces the fraction of patients deemed ineligible for MR-HIFU ablation of uterine fibroids due to interposed bowels, although care is needed when the uterus is small.

  9. Acoustic Cavitation Enhances Focused Ultrasound Ablation with Phase-Shift Inorganic Perfluorohexane Nanoemulsions: An In Vitro Study Using a Clinical Device

    Directory of Open Access Journals (Sweden)

    Lu-Yan Zhao

    2016-01-01

    Full Text Available Purpose. To investigate whether acoustic cavitation could increase the evaporation of a phase-shift inorganic perfluorohexane (PFH nanoemulsion and enhance high intensity focused ultrasound (HIFU ablation. Materials and Methods. PFH was encapsulated by mesoporous silica nanocapsule (MSNC to form a nanometer-sized droplet (MSNC-PFH. It was added to a tissue-mimicking phantom, whereas phosphate buffered saline (PBS was added as a control (PBS-control. HIFU (Pac=150 W, t=5/10 s exposures were performed in both phantoms with various duty cycles (DC. US images, temperature, and cavitation emissions were recorded during HIFU exposure. HIFU-induced lesions were measured and calculated. Results. Compared to PBS-control, MSNC-PFH nanoemulsion could significantly increase the volume of HIFU-induced lesion (P<0.01. Peak temperatures were 78.16 ± 5.64°C at a DC of 100%, 70.17 ± 6.43°C at 10%, 53.17 ± 4.54°C at 5%, and 42.00 ± 5.55°C at 2%, respectively. Inertial cavitation was much stronger in the pulsed-HIFU than that in the continuous-wave HIFU exposure. Compared to 100%-DC exposure, the mean volume of lesion induced by 5 s exposure at 10%-DC was significantly larger, but smaller at 2%-DC. Conclusions. MSNC-PFH nanoemulsion can significantly enhance HIFU ablation. Appropriate pulsed-HIFU exposure could significantly increase the volume of lesion and reduce total US energy required for HIFU ablation.

  10. Targeted delivery of erythropoietin by transcranial focused ultrasound for neuroprotection against ischemia/reperfusion-induced neuronal injury: a long-term and short-term study.

    Science.gov (United States)

    Wu, Sheng-Kai; Yang, Ming-Tao; Kang, Kai-Hsiang; Liou, Houng-Chi; Lu, Dai-Hua; Fu, Wen-Mei; Lin, Win-Li

    2014-01-01

    Erythropoietin (EPO) is a neuroprotective agent against cerebral ischemia/reperfusion (I/R)-induced brain injury. However, its crossing of blood-brain barrier is limited. Focused ultrasound (FUS) sonication with microbubbles (MBs) can effectively open blood-brain barrier to boost the vascular permeability. In this study, we investigated the effects of MBs/FUS on extending the therapeutic time window of EPO and its neuroprotective effects in both acute and chronic phases. Male Wistar rats were firstly subjected to two common carotid arteries and right middle cerebral artery occlusion (three vessels occlusion, 3VO) for 50 min, and then the rats were treated with hEPO (human recombinant EPO, 5000 IU/kg) with or without MBs/FUS at 5 h after occlusion/reperfusion. Acute phase investigation (I/R, I/R+MBs/FUS, I/R+hEPO, and I/R+hEPO+MBs/FUS) was performed 24 h after I/R; chronic tests including cylinder test and gait analysis were performed one month after I/R. The experimental results showed that MBs/FUS significantly increased the cerebral content of EPO by bettering vascular permeability. In acute phase, both significant improvement of neurological score and reduction of infarct volume were found in the I/R+hEPO+MBs/FUS group, as compared with I/R and I/R+hEPO groups. In chronic phase, long-term behavioral recovery and neuronal loss in brain cortex after I/R injury was significantly improved in the I/R+hEPO+MBs/FUS group. This study indicates that hEPO administration with MBs/FUS sonication even at 5 h after occlusion/reperfusion can produce a significant neuroprotection. PMID:24587228

  11. The feasibility and safety of high-intensity focused ultrasound combined with low-dose external beam radiotherapy as supplemental therapy for advanced prostate cancer following hormonal therapy

    Institute of Scientific and Technical Information of China (English)

    Rui-Yi Wu; Guo-Min Wang; Lei Xu; Bo-Heng Zhang; Ye-Qing Xu; Zhao-Chong Zeng; Bing Chen

    2011-01-01

    The aim of this study was to investigate the feasibility and safety of high-intensity focused ultrasound (HIFU) combined with (+) low-dose external beam radiotherapy (LRT) as supplemental therapy for advanced prostate cancer (PCa) following hormonal therapy (HT). Our definition of HIFU+LRT refers to treating primary tumour lesions with HIFU in place of reduced field boost irradiation to the prostate, while retaining four-field box irradiation to the pelvis in conventional-dose external beam radiotherapy (CRT). We performed a prospective, controlled and non-randomized study on 120 patients with advanced PCa after HT who received HIFU, CRT, HIFU+LRT and HT alone, respectively. CT/MR imaging showed the primary tumours and pelvic lymph node metastases visibly shrank or even disappeared after HIFU+LRT treatment. There were significant differences among four groups with regard to overall survival (OS) and disease-specific survival (DSS) curves (P=0.018 and 0.015). Further comparison between each pair of groups suggested that the long-term DSS of the HIFU+LRT group was higher than those of the other three groups, but there was no significant difference between the HIFU+LRT group and the CRT group. Multivariable Cox's proportional hazard model showed that both HIFU+LRT and CRT were independently associated with DSS (P=0.001 and 0.035) and had protective effects with regard to the risk of death. Compared with CRT, HIFU+LRT significantly decreased incidences of radiation-related late gastrointestinal (GI) and genitourinary (GU) toxicity grade ≥II. In conclusion, long-term survival of patients with advanced PCa benefited from strengthening local control of primary tumour and regional lymph node metastases after HT. As an alternative to CRT, HIFU+LRT showed good efficacy and better safety.

  12. Long-Term Safety of Repeated Blood-Brain Barrier Opening via Focused Ultrasound with Microbubbles in Non-Human Primates Performing a Cognitive Task.

    Directory of Open Access Journals (Sweden)

    Matthew E Downs

    Full Text Available Focused Ultrasound (FUS coupled with intravenous administration of microbubbles (MB is a non-invasive technique that has been shown to reliably open (increase the permeability of the blood-brain barrier (BBB in multiple in vivo models including non-human primates (NHP. This procedure has shown promise for clinical and basic science applications, yet the safety and potential neurological effects of long term application in NHP requires further investigation under parameters shown to be efficacious in that species (500 kHz, 200-400 kPa, 4-5 μm MB, 2 minute sonication. In this study, we repeatedly opened the BBB in the caudate and putamen regions of the basal ganglia of 4 NHP using FUS with systemically-administered MB over 4-20 months. We assessed the safety of the FUS with MB procedure using MRI to detect edema or hemorrhaging in the brain. Contrast enhanced T1-weighted MRI sequences showed a 98% success rate for openings in the targeted regions. T2-weighted and SWI sequences indicated a lack edema in the majority of the cases. We investigated potential neurological effects of the FUS with MB procedure through quantitative cognitive testing of' visual, cognitive, motivational, and motor function using a random dot motion task with reward magnitude bias presented on a touchpanel display. Reaction times during the task significantly increased on the day of the FUS with MB procedure. This increase returned to baseline within 4-5 days after the procedure. Visual motion discrimination thresholds were unaffected. Our results indicate FUS with MB can be a safe method for repeated opening of the BBB at the basal ganglia in NHP for up to 20 months without any long-term negative physiological or neurological effects with the parameters used.

  13. High intensity focused ultrasound (HIFU) applied to hepato-bilio-pancreatic and the digestive system—current state of the art and future perspectives

    Science.gov (United States)

    Diana, Michele; Schiraldi, Luigi; Liu, Yu-Yin; Memeo, Riccardo; Mutter, Didier; Pessaux, Patrick

    2016-01-01

    Background High intensity focused ultrasound (HIFU) is emerging as a valid minimally-invasive image-guided treatment of malignancies. We aimed to review to current state of the art of HIFU therapy applied to the digestive system and discuss some promising avenues of the technology. Methods Pertinent studies were identified through PubMed and Embase search engines using the following keywords, combined in different ways: HIFU, esophagus, stomach, liver, pancreas, gallbladder, colon, rectum, and cancer. Experimental proof of the concept of endoluminal HIFU mucosa/submucosa ablation using a custom-made transducer has been obtained in vivo in the porcine model. Results Forty-four studies reported on the clinical use of HIFU to treat liver lesions, while 19 series were found on HIFU treatment of pancreatic cancers and four studies included patients suffering from both liver and pancreatic cancers, reporting on a total of 1,682 and 823 cases for liver and pancreas, respectively. Only very limited comparative prospective studies have been reported. Conclusions Digestive system clinical applications of HIFU are limited to pancreatic and liver cancer. It is safe and well tolerated. The exact place in the hepatocellular carcinoma (HCC) management algorithm remains to be defined. HIFU seems to add clear survival advantages over trans arterial chemo embolization (TACE) alone and similar results when compared to radio frequency (RF). For pancreatic cancer, HIFU achieves consistent cancer-related pain relief. Further research is warranted to improve targeting accuracy and efficacy monitoring. Furthermore, additional work is required to transfer this technology on appealing treatments such as endoscopic HIFU-based therapies. PMID:27500145

  14. First clinical experience of intra-operative high intensity focused ultrasound in patients with colorectal liver metastases: a phase I-IIa study.

    Directory of Open Access Journals (Sweden)

    Aurélien Dupré

    Full Text Available Surgery is the only curative treatment in patients with colorectal liver metastases (CLM, but only 10-20% of patients are eligible. High Intensity Focused Ultrasound (HIFU technology is of proven value in several indications, notably prostate cancer. Its intra-operative use in patients with CLM has not previously been studied. Preclinical work suggested the safety and feasibility of a new HIFU device capable of ablating volumes of up to 2cm x 2cm in a few seconds.We conducted a prospective, single-centre phase I-IIa trial. HIFU was delivered immediately before scheduled hepatectomy. To demonstrate the safety and efficacy of rapidly ablating liver parenchyma, ablations were performed on healthy tissue within the areas scheduled for resection.In total, 30 ablations were carried out in 15 patients. These ablations were all generated within 40 seconds and on average measured 27.5mm x 21.0mm. The phase I study (n = 6 showed that use of the HIFU device was feasible and safe and did not damage neighbouring tissue. The phase IIa study (n = 9 showed both that the area of ablation could be precisely targeted on a previously implanted metallic mark (used to represent a major anatomical structure and that ablations could be undertaken deliberately to avoid such a mark. Ablations were achieved with a precision of 1-2 mm.HIFU was feasible, safe and effective in ablating areas of liver scheduled for resection. The next stage is a phase IIb study which will attempt ablation of small metastases with a 5 mm margin, again prior to planned resection.ClinicalTrials.govNCT01489787.

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

    International Nuclear Information System (INIS)

    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

  16. Electron acceleration by electron plasma wave excited by beating two cross-focused Cosh-Gaussian laser beams in collisionless plasma

    International Nuclear Information System (INIS)

    This paper presents a scheme for electron acceleration by excitation of an electron plasma wave (EPW) by beating two cross focused Cosh-Gaussian (ChG) laser beams in an underdense plasma where ponderomotive nonlinearity is operative. The ponderomotive nonlinearity depends not only on the intensity of first laser beam but also on that of second laser beam. Therefore, the propagation dynamics of one laser beam affects that of other and hence, cross-focusing of the two laser beams takes place. Virial theorem technique has been invoked to study the propagation dynamics of the laser beams. Due to nonuniform intensity distribution along the wavefronts of the laser beams, the background electron concentration gets modified. The amplitude of EPW, which depends on the background electron concentration, is thus nonlinearly coupled with the laser beams. The effects of ponderomotive nonlinearity and cross-focusing of the laser beams on excitation of EPW have been incorporated. The generated plasma wave produces regions of positive and negative charges and thus establishes an electric field that travels along with the plasma wave. If a charged particle is injected into the plasma at approximately the same velocity as plasma wave, it will stay in phase with the field, absorb energy from the field and accelerate steadily. It has been found that by changing the decentered parameter the peak intensity of ChG laser beam can be shifted in the transverse direction and hence, optimum acceleration of the electrons can be obtained. The plasma based electron accelerators can adieu to the era of gargantuan mega-accelerators. (author)

  17. SIMULATION OF ENERGETIC PARTICLE TRANSPORT AND ACCELERATION AT SHOCK WAVES IN A FOCUSED TRANSPORT MODEL: IMPLICATIONS FOR MIXED SOLAR PARTICLE EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Kartavykh, Y. Y.; Dröge, W. [Institut für Theoretische Physik und Astrophysik, Universität Würzburg, D-97074 Würzburg (Germany); Gedalin, M. [Department of Physics, Ben-Gurion Unversity of the Negev, Beer-Sheva (Israel)

    2016-03-20

    We use numerical solutions of the focused transport equation obtained by an implicit stochastic differential equation scheme to study the evolution of the pitch-angle dependent distribution function of protons in the vicinity of shock waves. For a planar stationary parallel shock, the effects of anisotropic distribution functions, pitch-angle dependent spatial diffusion, and first-order Fermi acceleration at the shock are examined, including the timescales on which the energy spectrum approaches the predictions of diffusive shock acceleration theory. We then consider the case that a flare-accelerated population of ions is released close to the Sun simultaneously with a traveling interplanetary shock for which we assume a simplified geometry. We investigate the consequences of adiabatic focusing in the diverging magnetic field on the particle transport at the shock, and of the competing effects of acceleration at the shock and adiabatic energy losses in the expanding solar wind. We analyze the resulting intensities, anisotropies, and energy spectra as a function of time and find that our simulations can naturally reproduce the morphologies of so-called mixed particle events in which sometimes the prompt and sometimes the shock component is more prominent, by assuming parameter values which are typically observed for scattering mean free paths of ions in the inner heliosphere and energy spectra of the flare particles which are injected simultaneously with the release of the shock.

  18. Simulation of Energetic Particle Transport and Acceleration at Shock Waves in a Focused Transport Model: Implications for Mixed Solar Particle Events

    Science.gov (United States)

    Kartavykh, Y. Y.; Dröge, W.; Gedalin, M.

    2016-03-01

    We use numerical solutions of the focused transport equation obtained by an implicit stochastic differential equation scheme to study the evolution of the pitch-angle dependent distribution function of protons in the vicinity of shock waves. For a planar stationary parallel shock, the effects of anisotropic distribution functions, pitch-angle dependent spatial diffusion, and first-order Fermi acceleration at the shock are examined, including the timescales on which the energy spectrum approaches the predictions of diffusive shock acceleration theory. We then consider the case that a flare-accelerated population of ions is released close to the Sun simultaneously with a traveling interplanetary shock for which we assume a simplified geometry. We investigate the consequences of adiabatic focusing in the diverging magnetic field on the particle transport at the shock, and of the competing effects of acceleration at the shock and adiabatic energy losses in the expanding solar wind. We analyze the resulting intensities, anisotropies, and energy spectra as a function of time and find that our simulations can naturally reproduce the morphologies of so-called mixed particle events in which sometimes the prompt and sometimes the shock component is more prominent, by assuming parameter values which are typically observed for scattering mean free paths of ions in the inner heliosphere and energy spectra of the flare particles which are injected simultaneously with the release of the shock.

  19. 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.)

  20. Improving the energy-extraction efficiency of laser-plasma accelerator driven free-electron laser using transverse-gradient undulator with focusing optics and longitudinal tapering

    CERN Document Server

    Zhou, G; Wu, J; Zhang, T

    2016-01-01

    It is reported that [Z. Huang et al., Phys. Rev. Lett. 109, 204801 (2012)], high-gain free-electron laser (FEL) can be generated by transverse-dispersed electron beams from laser-plasma accelerators (LPAs) using transverse-gradient undulator (TGU) assuming an ideal constant dispersion function without focusing optics. The constant dispersion function keeps electrons beyond the resonant energy bandwidth still being on resonant with the FEL radiation. Instead, in this paper, the case with focusing optics in an LPA-driven FEL using TGU is numerically studied, in which the dispersion function should be monotonously decreasing along the undulator. Even though the FEL resonance is not always satisfied for off-energy electrons in this case, through subtly optimizing the initial dispersion and focusing parameters, it is feasible to achieve a similar radiation power to the case assuming an ideal constant dispersion function without focusing optics, and meanwhile, to attain a good transverse coherence. Moreover, higher...

  1. Relationship between acceleration of hydroxyl radical initiation and increase of multiple-ultrasonic field amount in the process of ultrasound catalytic ozonation for degradation of nitrobenzene in aqueous solution.

    Science.gov (United States)

    Zhao, Lei; Ma, Weichao; Ma, Jun; Wen, Gang; Liu, Qianliang

    2015-01-01

    The synergetic effect between ozone and ultrasound can enhance the degradation of nitrobenzene and removal efficiency of TOC in aqueous solution, and the degradation of nitrobenzene follows the mechanism of hydroxyl radical (OH) oxidation. Under the same total ultrasonic power input condition, the degradation rate of nitrobenzene (kNB), the volumetric mass transfer coefficient of ozone (kLa), and the initiation rate of OH (kOH) increases with introduction of additional ultrasonic field (1-4) in the process of ozone/ultrasound. The increasing amount of ultrasonic fields accelerates the decomposition of ozone, leading to the rapid appearance of the maximum equilibrium value and the decrease in the accumulation concentration of ozone in aqueous solution with the increasing reaction time. The increase in mass transfer of gaseous ozone dissolved into aqueous solution and the acceleration in the decomposition of ozone in aqueous solution synchronously contribute to the increase of kLa. The investigation of mechanism confirms that the increasing amount of ultrasonic fields yields the increase in cavitation activity that improves the mass transfer and decomposition of ozone, resulting in acceleration of OH initiation, which determines the degradation of nitrobenzene in aqueous solution.

  2. 我国聚焦超声治疗技术的迅速崛起与展望%Rapid rise of focused ultrasound therapeutic technique and prospect in China

    Institute of Scientific and Technical Information of China (English)

    冯若

    2011-01-01

    Therapeutic ultrasound technique has now been considered as an advanced scientific technique in the world.High intensity focused ultrasound (HIFU) has become a new technique of treating tumors in the 2lst century and it has now successfully applied to ablating various tumors in clinic. Focused ultrasound technique has also gained great success in treating vulva dystrophy and cervicitis etc in gynecology which is attracting extensive attention. But there is a big developing space for these novel therapy techniques. This review will briefly point out the existed problems, faced challenges and responsive measures, which must be taken in order to keep the advanced position of our country in this field.%治疗超声技术被推选为当今世界的前沿科学技术.高强聚焦超声(High Intensity Focused Ultrasound,HIFU)技术被认为是21世纪治疗肿瘤的新技术,已被成功地用于临床"消融"多种肿瘤.我国在使用聚焦超声技术治疗妇科外阴白色病、宫颈炎等也取得巨大成功,引起广泛重视.但这些新的治疗技术仍有很大的发展空间.并且指出了存在的问题和面临的挑战,以及为确保我国在这一领域的领先地位需要采取的应对措施.

  3. 5. Accelerated Fracture Healing Targeting Periosteal Cells: Possibility of Combined Therapy of Low-Intensity Pulsed Ultrasound (LIPUS), Bone Graft, and Growth Factor (bFGF).

    Science.gov (United States)

    Uchida, Kentaro; Urabe, Ken; Naruse, Koji; Mikuni-Takagaki, Yuko; Inoue, Gen; Takaso, Masashi

    2016-08-01

    We have studied the mechanism of fracture healing, and the effect of LIPUS, bone graft and growth factor on accelerating fracture healing. We present here the results of our research. To examine callus formation cells in fracture healing, we made marrow GFP chimera mice and a fracture model of marrow mesenchymal stem cell GFP chimera mice. It was demonstrated that periosteal cells were essential for callus formation. We focused on periosteal cells and examined the effect of LIPUS. In an in vitro experiment using a cultured part of the femur, LIPUS promoted ossification of the periosteal tissue. Further, LIPUS accelerated VEGF expression in the experiment using the femoral fracture model of mice. From these results, it was suggested that activation of periosteal cells might play a role in the fracture healing mechanism of LIPUS. Next, we discussed the possibility of combined therapy of LIPUS, bone graft and growth factor. Therapy involving the topical administration of bFGF using a controlled release system and bone graft could promote callus formation. In addition, LIPUS was able to promote membranaceous ossification after the bone graft. It was suggested that combined therapy of LIPUS, bone graft and bFGF could be a new option for treating fractures. PMID:27441766

  4. Present status and first results of the final focus beam line at the KEK Accelerator Test Facility

    CERN Document Server

    Bambade, P; Amann, J; Angal-Kalinin, D; Apsimon, R; Araki, S; Aryshev, A; Bai, S; Bellomo, P; Bett, D; Blair, G; Bolzon, B; Boogert, S; Boorman, G; Burrows, P N; Christian, G; Coe, P; Constance, B; Delahaye, J P; Deacon, L; Elsen, E; Faus-Golfe, A; Fukuda, M; Gao, J; Geffroy, N; Gianfelice-Wendt, E; Guler, H; Hayano, H; Heo, A Y; Honda, Y; Huang, J Y; Hwang, W H; Iwashita, Y; Jeremie, A; Jones, J; Kamiya, Y; Karataev, P; Kim, E S; Kim, H S; Kim, S H; Komamiya, S; Kubo, K; Kume, T; Kuroda, S; Lam, B; Lyapin, A; Masuzawa, M; McCormick, D; Molloy, S; Naito, T; Nakamura, T; Nelson, J; Okamoto, D; Okugi, T; Oroku, M; Park, Y J; Parker, B; Paterson, E; Perry, C; Pivi, M; Raubenheimer, T; Renier, Y; Resta-Lopez, J; Rimbault, C; Ross, M; Sanuki, T; Scarfe, A; Schulte, D; Seryi, A; Spencer, C; Suehara, T; Sugahara, R; Swinson, C; Takahashi, T; Tauchi, T; Terunuma, N; Tomas, R; Urakawa, J; Urner, D; Verderi, M; Wang, M H; Warden, M; Wendt, M; White, G; Wittmer, W; Wolski, A; Woodley, M; Yamaguchi, Y; Yamanaka, T; Yan, Y; Yoda, H; Yokoya, K; Zhou, F; Zimmermann, F

    2010-01-01

    ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.

  5. Present Status And First Results of the Final Focus Beam Line at the KEK Accelerator Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Bambade, P.; /Orsay /KEK, Tsukuba; Alabau Pons, M.; /Valencia U., IFIC; Amann, J.; /SLAC; Angal-Kalinin, D.; /Daresbury; Apsimon, R.; /Oxford U., JAI; Araki, S.; Aryshev, A.; /KEK, Tsukuba; Bai, S.; /Beijing, Inst. High Energy Phys.; Bellomo, P.; /SLAC; Bett, D.; /Oxford U., JAI; Blair, G.; /Royal Holloway, U. of London; Bolzon, B.; /Savoie U.; Boogert, S.; Boorman, G.; /Royal Holloway, U. of London; Burrows, P.N.; Christian, G.; Coe, P.; Constance, B.; /Oxford U., JAI; Delahaye, Jean-Pierre; /CERN; Deacon, L.; /Royal Holloway, U. of London; Elsen, E.; /DESY /Valencia U., IFIC /KEK, Tsukuba /Beijing, Inst. High Energy Phys. /Savoie U. /Fermilab /Ecole Polytechnique /KEK, Tsukuba /Kyungpook Natl. U. /KEK, Tsukuba /Pohang Accelerator Lab. /Kyoto U., Inst. Chem. Res. /Savoie U. /Daresbury /Tokyo U. /Royal Holloway, U. of London /Kyungpook Natl. U. /Pohang Accelerator Lab. /Tokyo U. /KEK, Tsukuba /SLAC /University Coll. London /KEK, Tsukuba /SLAC /Royal Holloway, U. of London /KEK, Tsukuba /Tokyo U. /SLAC /Tohoku U. /KEK, Tsukuba /Tokyo U. /Pohang Accelerator Lab. /Brookhaven /SLAC /Oxford U., JAI /SLAC /Orsay /KEK, Tsukuba /Oxford U., JAI /Orsay /Fermilab /Tohoku U. /Manchester U. /CERN /SLAC /Tokyo U. /KEK, Tsukuba /Oxford U., JAI /Hiroshima U. /KEK, Tsukuba /CERN /KEK, Tsukuba /Oxford U., JAI /Ecole Polytechnique /SLAC /Oxford U., JAI /Fermilab /SLAC /Liverpool U. /SLAC /Tokyo U. /SLAC /Tokyo U. /KEK, Tsukuba /SLAC /CERN

    2011-11-11

    ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described.

  6. Delivery of Liposomes with Different Sizes to Mice Brain after Sonication by Focused Ultrasound in the Presence of Microbubbles.

    Science.gov (United States)

    Shen, Yuanyuan; Guo, Jinxuan; Chen, Gaoshu; Chin, Chien Ting; Chen, Xin; Chen, Jian; Wang, Feng; Chen, Shiguo; Dan, Guo

    2016-07-01

    Imaging or therapeutic agents larger than the blood-brain barrier's (BBB) exclusion threshold of 400 Da could be delivered locally, non-invasively and reversibly by focused ultrasound (FUS) with circulating microbubbles. The size of agents is an important factor to the delivery outcome using this method. Liposomes are important drug carriers with controllable sizes in a range of nanometers. However, discrepancies among deliveries of intact liposomes with different sizes, especially those larger than 50 nm, across the BBB opened by FUS with microbubbles remain unexplored. In the present study, rhodamine-labeled long-circulating pegylated liposomes with diameters of 55 nm, 120 nm and 200 nm were delivered to mice brains after BBB disruption by pulsed FUS with microbubbles. Four groups of peak rarefactional pressure and microbubble dosages were used: 0.53 MPa with 0.1 μL/g (group 1), 0.53 MPa with 0.5 μL/g (group 2), 0.64 MPa with 0.1 μL/g (group 3) and 0.64 MPa with 0.5 μL/g (group 4). The delivery outcome was observed using fluorescence imaging of brain sections. It was found that the delivery of 55-nm liposomes showed higher success rates than 120-nm or 200-nm liposomes from groups 1-3. The result indicated that it may be more difficult to deliver larger liposomes (>120 nm) passively than 55-nm liposomes after BBB opening by FUS with microbubbles. The relative fluorescence area of 55-nm liposomes to the total area of the sonicated region was statistically larger than that of the 120-nm or 200-nm liposomes. Increasing peak rarefactional pressure amplitude or microbubble dose could induce more accumulation of liposomes in the brain using FUS with microbubbles. Moreover, the distribution pattern of delivered liposomes was heterogeneous and characterized by separated fluorescence spots with cloud-like periphery surrounding a bright center, indicating confined diffusion in the extracellular matrix after extravasation from the microvasculature. These

  7. Non-invasive, neuron-specific gene therapy by focused ultrasound-induced blood-brain barrier opening in Parkinson's disease mouse model.

    Science.gov (United States)

    Lin, Chung-Yin; Hsieh, Han-Yi; Chen, Chiung-Mei; Wu, Shang-Rung; Tsai, Chih-Hung; Huang, Chiung-Yin; Hua, Mu-Yi; Wei, Kuo-Chen; Yeh, Chih-Kuang; Liu, Hao-Li

    2016-08-10

    Focused ultrasound (FUS)-induced with microbubbles (MBs) is a promising technique for noninvasive opening of the blood-brain barrier (BBB) to allow targeted delivery of therapeutic substances into the brain and thus the noninvasive delivery of gene vectors for CNS treatment. We have previously demonstrated that a separated gene-carrying liposome and MBs administration plus FUS exposure can deliver genes into the brain, with the successful expression of the reporter gene and glial cell line-derived neurotrophic factor (GDNF) gene. In this study, we further modify the delivery system by conjugating gene-carrying liposomes with MBs to improve the GDNF gene-delivery efficiency, and to verify the possibility of using this system to perform treatment in the 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced animal disease model. FUS-BBB opening was verified by contrast-enhanced MRI, and GFP gene expression was verified via in vivo imaging system (IVIS). Western blots as well as enzyme-linked immunosorbent assay (ELISA) were conducted to measure protein expression, and immunohistochemistry (IHC) was conducted to test the Tyrosine hydroxylase (TH)-neuron distribution. Dopamine (DA) and its metabolites as well as dopamine active transporter (DAT) were quantitatively analyzed to show dopaminergic neuronal dopamine secretion/activity/metabolism. Motor performance was evaluated by rotarod test weekly. Results demonstrated that the LpDNA-MBs (gene-liposome-MBs) complexes successfully serve as gene carrier and BBB-opening catalyst, and outperformed the separated LpDNA/MBs administration both in terms of gene delivery and expression. TH-positive IHC and measurement of DA and its metabolites DOPAC and HVA confirmed improved neuronal function, and the proposed system also provided the best neuroprotective effect to retard the progression of motor-related behavioral abnormalities. Immunoblotting and histological staining further confirmed the expression of reporter genes in

  8. Magnetic-resonance imaging for kinetic analysis of permeability changes during focused ultrasound-induced blood-brain barrier opening and brain drug delivery.

    Science.gov (United States)

    Chai, Wen-Yen; Chu, Po-Chun; Tsai, Meng-Yen; Lin, Yu-Chun; Wang, Jiun-Jie; Wei, Kuo-Chen; Wai, Yau-Yau; Liu, Hao-Li

    2014-10-28

    Focused ultrasound (FUS) with the presence of microbubbles has been shown to induce transient and local opening of the blood-brain barrier (BBB) for the delivery of therapeutic molecules which normally cannot penetrate into the brain. The success of FUS brain-drug delivery relies on its integration with in-vivo imaging to monitor kinetic change of therapeutic molecules into the brain. In this study, we developed a dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique for kinetic analysis of delivered molecules during FUS-BBB opening. Three kinetic parameters (Ktrans, Ve, Kep) were characterized dynamically to describe BBB-permeability at two FUS exposure conditions (0.4 or 0.8MPa) over 24h. Ktrans, defined as the influx volume transfer constant from plasma to EES, and Ve, the EES volume fraction, were both found to be pressure-dependent. Ktrans and Ve showed a peak increase of 0.0086-0.0131min(-1) (for 0.4-0.8MPa pressure), and 0.0431-0.0692, respectively, immediately after FUS exposure. Both parameters subsequently decreased exponentially as a function of time, with estimated half-lives of decay of 2.89-5.3 and 2.2-4.93h, respectively. The kinetics of Kep, defined as the efflux rate constant from the extracellular extravascular space (EES) to the plasma, were complementary to Ktrans, with an initial decrease from 0.2010 to 0.1901min(-1) followed by a significantly longer recovery time (half-life of 17.39-99.92h). Our observations strongly supported the existence of imbalanced and mismatched kinetics of influx (Ktrans) and efflux (Kep) between the plasma and EES, indicating the existence of directional permeability during FUS-BBB opening. We further showed that kinetic change determined by DCE-MRI correlated well with the concentration of Evans Blue (EB)-albumin (coefficient of 0.74-0.89). These findings suggest that MRI kinetic monitoring