ultrasound image guidance: Topics by WorldWideScience.org

Sample records for ultrasound image guidance

Virtual Ultrasound Guidance for Inexperienced Operators

Science.gov (United States)

Caine, Timothy; Martin, David

2012-01-01

Medical ultrasound or echocardiographic studies are highly operator-dependent and generally require lengthy training and internship to perfect. To obtain quality echocardiographic images in remote environments, such as on-orbit, remote guidance of studies has been employed. This technique involves minimal training for the user, coupled with remote guidance from an expert. When real-time communication or expert guidance is not available, a more autonomous system of guiding an inexperienced operator through an ultrasound study is needed. One example would be missions beyond low Earth orbit in which the time delay inherent with communication will make remote guidance impractical. The Virtual Ultrasound Guidance system is a combination of hardware and software. The hardware portion includes, but is not limited to, video glasses that allow hands-free, full-screen viewing. The glasses also allow the operator a substantial field of view below the glasses to view and operate the ultrasound system. The software is a comprehensive video program designed to guide an inexperienced operator through a detailed ultrasound or echocardiographic study without extensive training or guidance from the ground. The program contains a detailed description using video and audio to demonstrate equipment controls, ergonomics of scanning, study protocol, and scanning guidance, including recovery from sub-optimal images. The components used in the initial validation of the system include an Apple iPod Classic third-generation as the video source, and Myvue video glasses. Initially, the program prompts the operator to power-up the ultrasound and position the patient. The operator would put on the video glasses and attach them to the video source. After turning on both devices and the ultrasound system, the audio-video guidance would then instruct on patient positioning and scanning techniques. A detailed scanning protocol follows with descriptions and reference video of each view along with
Accuracy of Ultrasound-Based Image Guidance for Daily Positioning of the Upper Abdomen: An Online Comparison With Cone Beam CT

International Nuclear Information System (INIS)

Boda-Heggemann, Judit; Mennemeyer, Philipp; Wertz, Hansjoerg; Riesenacker, Nadja; Kuepper, Beate; Lohr, Frank; Wenz, Frederik

2009-01-01

Purpose: Image-guided intensity-modulated radiotherapy can improve protection of organs at risk when large abdominal target volumes are irradiated. We estimated the daily positioning accuracy of ultrasound-based image guidance for abdominal target volumes by a direct comparison of daily imaging obtained with cone beam computed tomography (CBCT). Methods and Materials: Daily positioning (n = 83 positionings) of 15 patients was completed by using ultrasound guidance after an initial CBCT was obtained. Residual error after ultrasound was estimated by comparison with a second CBCT. Ultrasound image quality was visually rated using a scale of 1 to 4. Results: Of 15 patients, 7 patients had good sonographic imaging quality, 5 patients had satisfactory sonographic quality, and 3 patients were excluded because of unsatisfactory sonographic quality. When image quality was good, residual errors after ultrasound were -0.1 ± 3.11 mm in the x direction (left-right; group systematic error M = -0.09 mm; standard deviation [SD] of systematic error, Σ = 1.37 mm; SD of the random error, σ = 2.99 mm), 0.93 ± 4.31 mm in the y direction (superior-inferior, M = 1.12 mm; Σ = 2.96 mm; σ = 3.39 mm), and 0.71 ± 3.15 mm in the z direction (anteroposterior; M = 1.01 mm; Σ = 2.46 mm; σ = 2.24 mm). For patients with satisfactory image quality, residual error after ultrasound was -0.6 ± 5.26 mm in the x (M = 0.07 mm; Σ = 5.67 mm; σ = 4.86 mm), 1.76 ± 4.92 mm in the y (M = 3.54 mm; Σ = 4.1 mm; σ = 5.29 mm), and 1.19 ± 4.75 mm in the z (M = 0.82 mm; Σ = 2.86 mm; σ = 3.05 mm) directions. Conclusions: In patients from whom good sonographic image quality could be obtained, ultrasound improved daily positioning accuracy. In the case of satisfactory image quality, ultrasound guidance improved accuracy compared to that of skin marks only minimally. If sonographic image quality was unsatisfactory, daily CBCT scanning improved treatment accuracy distinctly over that of ultrasound. Use of
Intraluminal laser atherectomy with ultrasound and electromagnetic guidance

Science.gov (United States)

Gregory, Kenton W.; Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Hatch, G. F.; Gregg, Richard E.; Sedlacek, Tomas; Haase, Wayne C.

1991-05-01

The MagellanTM coronary laser atherectomy system is described. It uses high- resolution ultrasound imaging and electromagnetic sensing to provide real-time guidance and control of laser therapy in the coronary arteries. The system consists of a flexible catheter, an electromagnetic navigation antenna, a sensor signal processor and a computer for image processing and display. The small, flexible catheter combines an ultrasound transducer and laser delivery optics, aimed at the artery wall, and an electromagnetic receiving sensor. An extra-corporeal electromagnetic transmit antenna, in combination with catheter sensors, locates the position of the ultrasound and laser beams in the artery. Navigation and ultrasound data are processed electronically to produce real-time, transverse, and axial cross-section images of the artery wall at selected locations. By exploiting the ability of ultrasound to image beneath the surface of artery walls, it is possible to identify candidate treatment sites and perform safe radial laser debulking of atherosclerotic plaque with reduced danger of perforation. The utility of the system in plaque identification and ablation is demonstrated with imaging and experimental results.
Ultrasound and PET-CT image fusion for prostate brachytherapy image guidance

International Nuclear Information System (INIS)

Hasford, F.

2015-01-01

Fusion of medical images between different cross-sectional modalities is widely used, mostly where functional images are fused with anatomical data. Ultrasound has for some time now been the standard imaging technique used for treatment planning of prostate cancer cases. While this approach is laudable and has yielded some positive results, latest developments have been the integration of images from ultrasound and other modalities such as PET-CT to compliment missing properties of ultrasound images. This study has sought to enhance diagnosis and treatment of prostate cancers by developing MATLAB algorithms to fuse ultrasound and PET-CT images. The fused ultrasound-PET-CT image has shown to contain improved quality of information than the individual input images. The fused image has the property of reduced uncertainty, increased reliability, robust system performance, and compact representation of information. The objective of co-registering the ultrasound and PET-CT images was achieved by conducting performance evaluation of the ultrasound and PET-CT imaging systems, developing image contrast enhancement algorithm, developing MATLAB image fusion algorithm, and assessing accuracy of the fusion algorithm. Performance evaluation of the ultrasound brachytherapy system produced satisfactory results in accordance with set tolerances as recommended by AAPM TG 128. Using an ultrasound brachytherapy quality assurance phantom, average axial distance measurement of 10.11 ± 0.11 mm was estimated. Average lateral distance measurements of 10.08 ± 0.07 mm, 20.01 ± 0.06 mm, 29.89 ± 0.03 mm and 39.84 ± 0.37 mm were estimated for the inter-target distances corresponding to 10 mm, 20 mm, 30 mm and 40 mm respectively. Volume accuracy assessment produced measurements of 3.97 cm 3 , 8.86 cm 3 and 20.11 cm 3 for known standard volumes of 4 cm 3 , 9 cm 3 and 20 cm 3 respectively. Depth of penetration assessment of the ultrasound system produced an estimate of 5.37 ± 0.02 cm
Efficacy and safety in performing of large bore percutaneous nephrostomy under ultrasound guidance

International Nuclear Information System (INIS)

Smilov, N.; Mlachkova, D.; Rizov, A.; Lozev, I.

2009-01-01

The aim of the study was to compare the success rate, complications and the outcomes from large-bore percutaneous nephrostomy under ultrasound guidance performed to 178 cases with another 54 when nephrostomy under x-ray control was performed. We have performed 178 large-bore percutaneous nephrostomy under ultrasound guidance and another 54 percutaneous nephrostomy under x-ray guidance to patients diagnosed with obstructive uropathy resulting from benign or malignant supravesical obstruction. We have performed successful nephrostomy in 93,8% of the cases under ultrasound guidance and 100% successful nephrostomy in the cases under x-ray control. In 2,8% of patients under ultrasound guidance the nephrostomy was performed using 4 additional punctures of the pyelocaliceal system and artificially caused hydronephrosis via infiltration of normal saline; and in the remaining 1,7% it was successful at the second attempt after 24 hours. It was not necessary to perform open surgery nephrostomy in any of the cases. The performance of percutaneous nephrostomy under ultrasound guidance has a success rate similar to the one done under x-ray guidance and with commensurable frequency and severity of complications, however without the patient and the operator being exposed to x-ray radiation. In general, the percutaneous nephrostomy under ultrasound guidance is performed without difficulties in the cases of third or fourth degree hydronephrosis. The lateral decubital patient position, the appropriate place for the puncture, the usage of Color Doppler imaging when the puncture is performed and the continuos ultrasound guidance during dilatation and placement of the nephrostomy tube should ensure the successful performance of the procedure in the case of first or second degree hydronephrosis. When hydronephrosis is absent, the nephrostomy should be performed under x-ray guidance. In emergency cases the application of ultrasound guidance allows the nephrostomy to be performed along the
Ultrasound-based guidance of intensity-modulated radiation therapy

International Nuclear Information System (INIS)

Fung, Albert Y.C.; Ayyangar, Komanduri M.; Djajaputra, David; Nehru, Ramasamy M.; Enke, Charles A.

2006-01-01

In ultrasound-guided intensity-modulated radiation therapy (IMRT) of prostate cancer, ultrasound imaging ascertains the anatomical position of patients during x-ray therapy delivery. The ultrasound transducers are made of piezoelectric ceramics. The same crystal is used for both ultrasound production and reception. Three-dimensional (3D) ultrasound devices capture and correlate series of 2-dimensional (2D) B-mode images. The transducers are often arranged in a convex array for focusing. Lower frequency reaches greater depth, but results in low resolution. For clear image, some gel is usually applied between the probe and the skin contact surface. For prostate positioning, axial and sagittal scans are performed, and the volume contours from computed tomography (CT) planning are superimposed on the ultrasound images obtained before radiation delivery at the linear accelerator. The planning volumes are then overlaid on the ultrasound images and adjusted until they match. The computer automatically deduces the offset necessary to move the patient so that the treatment area is in the correct location. The couch is translated as needed. The currently available commercial equipment can attain a positional accuracy of 1-2 mm. Commercial manufacturer designs differ in the detection of probe coordinates relative to the isocenter. Some use a position-sensing robotic arm, while others have infrared light-emitting diodes or pattern-recognition software with charge-couple-device cameras. Commissioning includes testing of image quality and positional accuracy. Ultrasound is mainly used in prostate positioning. Data for 7825 daily fractions of 234 prostate patients indicated average 3D inter-fractional displacement of about 7.8 mm. There was no perceivable trend of shift over time. Scatter plots showed slight prevalence toward superior-posterior directions. Uncertainties of ultrasound guidance included tissue inhomogeneities, speckle noise, probe pressure, and inter
Intraoperative registered transrectal ultrasound guidance for robot-assisted laparoscopic radical prostatectomy.

Science.gov (United States)

Mohareri, Omid; Ischia, Joseph; Black, Peter C; Schneider, Caitlin; Lobo, Julio; Goldenberg, Larry; Salcudean, Septimiu E

2015-01-01

To provide unencumbered real-time ultrasound image guidance during robot-assisted laparoscopic radical prostatectomy, we developed a robotic transrectal ultrasound system that tracks the da Vinci® Surgical System instruments. We describe our initial clinical experience with this system. After an evaluation in a canine model, 20 patients were enrolled in the study. During each procedure the transrectal ultrasound transducer was manually positioned using a brachytherapy stabilizer to provide good imaging of the prostate. Then the transrectal ultrasound was registered to the da Vinci robot by a previously validated procedure. Finally, automatic rotation of the transrectal ultrasound was enabled such that the transrectal ultrasound imaging plane safely tracked the tip of the da Vinci instrument controlled by the surgeon, while real-time transrectal ultrasound images were relayed to the surgeon at the da Vinci console. Tracking was activated during all critical stages of the surgery. The transrectal ultrasound robot was easy to set up and use, adding 7 minutes (range 5 to 14) to the procedure. It did not require an assistant or additional control devices. Qualitative feedback was acquired from the surgeons, who found transrectal ultrasound useful in identifying the urethra while passing the dorsal venous complex suture, defining the prostate-bladder interface during bladder neck dissection, identifying the seminal vesicles and their location with respect to the rectal wall, and identifying the distal prostate boundary at the apex. Real-time, registered robotic transrectal ultrasound guidance with automatic instrument tracking during robot-assisted laparoscopic radical prostatectomy is feasible and potentially useful. The results justify further studies to establish whether the approach can improve procedure outcomes. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Ultrasound Guidance for Botulinum Neurotoxin Chemodenervation Procedures

Directory of Open Access Journals (Sweden)

Katharine E. Alter

2017-12-01

Full Text Available Injections of botulinum neurotoxins (BoNTs are prescribed by clinicians for a variety of disorders that cause over-activity of muscles; glands; pain and other structures. Accurately targeting the structure for injection is one of the principle goals when performing BoNTs procedures. Traditionally; injections have been guided by anatomic landmarks; palpation; range of motion; electromyography or electrical stimulation. Ultrasound (US based imaging based guidance overcomes some of the limitations of traditional techniques. US and/or US combined with traditional guidance techniques is utilized and or recommended by many expert clinicians; authors and in practice guidelines by professional academies. This article reviews the advantages and disadvantages of available guidance techniques including US as well as technical aspects of US guidance and a focused literature review related to US guidance for chemodenervation procedures including BoNTs injection.
SU-C-207B-07: Deep Convolutional Neural Network Image Matching for Ultrasound Guidance in Radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Zhu, N; Najafi, M; Hancock, S; Hristov, D [Stanford University Cancer Center, Palo Alto, CA (United States)

2016-06-15

Purpose: Robust matching of ultrasound images is a challenging problem as images of the same anatomy often present non-trivial differences. This poses an obstacle for ultrasound guidance in radiotherapy. Thus our objective is to overcome this obstacle by designing and evaluating an image blocks matching framework based on a two channel deep convolutional neural network. Methods: We extend to 3D an algorithmic structure previously introduced for 2D image feature learning [1]. To obtain the similarity between two 3D image blocks A and B, the 3D image blocks are divided into 2D patches Ai and Bi. The similarity is then calculated as the average similarity score of Ai and Bi. The neural network was then trained with public non-medical image pairs, and subsequently evaluated on ultrasound image blocks for the following scenarios: (S1) same image blocks with/without shifts (A and A-shift-x); (S2) non-related random block pairs; (S3) ground truth registration matched pairs of different ultrasound images with/without shifts (A-i and A-reg-i-shift-x). Results: For S1 the similarity scores of A and A-shift-x were 32.63, 18.38, 12.95, 9.23, 2.15 and 0.43 for x=ranging from 0 mm to 10 mm in 2 mm increments. For S2 the average similarity score for non-related block pairs was −1.15. For S3 the average similarity score of ground truth registration matched blocks A-i and A-reg-i-shift-0 (1≤i≤5) was 12.37. After translating A-reg-i-shift-0 by 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm, the average similarity scores of A-i and A-reg-i-shift-x were 11.04, 8.42, 4.56, 2.27, and 0.29 respectively. Conclusion: The proposed method correctly assigns highest similarity to corresponding 3D ultrasound image blocks despite differences in image content and thus can form the basis for ultrasound image registration and tracking.[1] Zagoruyko, Komodakis, “Learning to compare image patches via convolutional neural networks', IEEE CVPR 2015,pp.4353–4361.
SU-C-207B-07: Deep Convolutional Neural Network Image Matching for Ultrasound Guidance in Radiotherapy

International Nuclear Information System (INIS)

Zhu, N; Najafi, M; Hancock, S; Hristov, D

2016-01-01

Purpose: Robust matching of ultrasound images is a challenging problem as images of the same anatomy often present non-trivial differences. This poses an obstacle for ultrasound guidance in radiotherapy. Thus our objective is to overcome this obstacle by designing and evaluating an image blocks matching framework based on a two channel deep convolutional neural network. Methods: We extend to 3D an algorithmic structure previously introduced for 2D image feature learning [1]. To obtain the similarity between two 3D image blocks A and B, the 3D image blocks are divided into 2D patches Ai and Bi. The similarity is then calculated as the average similarity score of Ai and Bi. The neural network was then trained with public non-medical image pairs, and subsequently evaluated on ultrasound image blocks for the following scenarios: (S1) same image blocks with/without shifts (A and A-shift-x); (S2) non-related random block pairs; (S3) ground truth registration matched pairs of different ultrasound images with/without shifts (A-i and A-reg-i-shift-x). Results: For S1 the similarity scores of A and A-shift-x were 32.63, 18.38, 12.95, 9.23, 2.15 and 0.43 for x=ranging from 0 mm to 10 mm in 2 mm increments. For S2 the average similarity score for non-related block pairs was −1.15. For S3 the average similarity score of ground truth registration matched blocks A-i and A-reg-i-shift-0 (1≤i≤5) was 12.37. After translating A-reg-i-shift-0 by 0 mm, 2 mm, 4 mm, 6 mm, 8 mm, and 10 mm, the average similarity scores of A-i and A-reg-i-shift-x were 11.04, 8.42, 4.56, 2.27, and 0.29 respectively. Conclusion: The proposed method correctly assigns highest similarity to corresponding 3D ultrasound image blocks despite differences in image content and thus can form the basis for ultrasound image registration and tracking.[1] Zagoruyko, Komodakis, “Learning to compare image patches via convolutional neural networks', IEEE CVPR 2015,pp.4353–4361.
Intraluminal ultrasound guidance of transverse laser coronary atherectomy

Science.gov (United States)

Aretz, H. Thomas; Martinelli, Michael A.; LeDet, Earl G.; Sedlacek, Tomas; Hatch, G. F.; Gregg, Richard E.

1990-07-01

A coronary laser atherectomy system combining laser delivery and ultrasonic imaging capability is described. The system is being developed by Intra-Sonix, Inc. to treat severe stenoses. The imaging system provides the clinician with the guidance needed to remove substantial plaque without perforation. The ultrasound transducers and laser optics are mounted in a small (less than 4 F), flexible catheter, that is deliverable over a standard guidewire (0.016 inch). The laser and ultrasound beams are directed at the artery wall to permit debulking of lesions and ultrasonic depth profiling of the tissue structure throughout the thickness of the artery. This allows the physician to determine the level of therapy to be applied and to monitor the plaque removal as the therapy progresses. The precise location of the ultrasound and laser beams in the artery is determined by a navigation system. Navigation data are processed electronically in conjunction with ultrasound data to produce real-time cross-sectional and longitudinal images of the artery wall at selected locations, which are updated as the catheter progresses through the vessel lumen. Results of in vitro tests on human atherosclerotic arteries and early in vivo experiments in a canine-human xenograft model showing image construction and radial laser delivery are discussed.
Percutaneous Thermal Ablation with Ultrasound Guidance. Fusion Imaging Guidance to Improve Conspicuity of Liver Metastasis

Energy Technology Data Exchange (ETDEWEB)

Hakime, Antoine, E-mail: thakime@yahoo.com; Yevich, Steven; Tselikas, Lambros; Deschamps, Frederic [Gustave Roussy - Cancer Campus, Interventional Radiology Department (France); Petrover, David [Imagerie Médicale Paris Centre, IMPC (France); Baere, Thierry De [Gustave Roussy - Cancer Campus, Interventional Radiology Department (France)

2017-05-15

PurposeTo assess whether fusion imaging-guided percutaneous microwave ablation (MWA) can improve visibility and targeting of liver metastasis that were deemed inconspicuous on ultrasound (US).Materials and MethodsMWA of liver metastasis not judged conspicuous enough on US was performed under CT/US fusion imaging guidance. The conspicuity before and after the fusion imaging was graded on a five-point scale, and significance was assessed by Wilcoxon test. Technical success, procedure time, and procedure-related complications were evaluated.ResultsA total of 35 patients with 40 liver metastases (mean size 1.3 ± 0.4 cm) were enrolled. Image fusion improved conspicuity sufficiently to allow fusion-targeted MWA in 33 patients. The time required for image fusion processing and tumors’ identification averaged 10 ± 2.1 min (range 5–14). Initial conspicuity on US by inclusion criteria was 1.2 ± 0.4 (range 0–2), while conspicuity after localization on fusion imaging was 3.5 ± 1 (range 1–5, p < 0.001). Technical success rate was 83% (33/40) in intention-to-treat analysis and 100% in analysis of treated tumors. There were no major procedure-related complications.ConclusionsFusion imaging broadens the scope of US-guided MWA to metastasis lacking adequate conspicuity on conventional US. Fusion imaging is an effective tool to increase the conspicuity of liver metastases that were initially deemed non visualizable on conventional US imaging.
Evaluation of alignment error due to a speed artifact in stereotactic ultrasound image guidance

International Nuclear Information System (INIS)

Salter, Bill J; Wang, Brian; Szegedi, Martin W; Rassiah-Szegedi, Prema; Shrieve, Dennis C; Cheng, Roger; Fuss, Martin

2008-01-01

Ultrasound (US) image guidance systems used in radiotherapy are typically calibrated for soft tissue applications, thus introducing errors in depth-from-transducer representation when used in media with a different speed of sound propagation (e.g. fat). This error is commonly referred to as the speed artifact. In this study we utilized a standard US phantom to demonstrate the existence of the speed artifact when using a commercial US image guidance system to image through layers of simulated body fat, and we compared the results with calculated/predicted values. A general purpose US phantom (speed of sound (SOS) = 1540 m s -1 ) was imaged on a multi-slice CT scanner at a 0.625 mm slice thickness and 0.5 mm x 0.5 mm axial pixel size. Target-simulating wires inside the phantom were contoured and later transferred to the US guidance system. Layers of various thickness (1-8 cm) of commercially manufactured fat-simulating material (SOS = 1435 m s -1 ) were placed on top of the phantom to study the depth-related alignment error. In order to demonstrate that the speed artifact is not caused by adding additional layers on top of the phantom, we repeated these measurements in an identical setup using commercially manufactured tissue-simulating material (SOS = 1540 m s -1 ) for the top layers. For the fat-simulating material used in this study, we observed the magnitude of the depth-related alignment errors resulting from the speed artifact to be 0.7 mm cm -1 of fat imaged through. The measured alignment errors caused by the speed artifact agreed with the calculated values within one standard deviation for all of the different thicknesses of fat-simulating material studied here. We demonstrated the depth-related alignment error due to the speed artifact when using US image guidance for radiation treatment alignment and note that the presence of fat causes the target to be aliased to a depth greater than it actually is. For typical US guidance systems in use today, this will
Evaluation of alignment error due to a speed artifact in stereotactic ultrasound image guidance.

Science.gov (United States)

Salter, Bill J; Wang, Brian; Szegedi, Martin W; Rassiah-Szegedi, Prema; Shrieve, Dennis C; Cheng, Roger; Fuss, Martin

2008-12-07

Ultrasound (US) image guidance systems used in radiotherapy are typically calibrated for soft tissue applications, thus introducing errors in depth-from-transducer representation when used in media with a different speed of sound propagation (e.g. fat). This error is commonly referred to as the speed artifact. In this study we utilized a standard US phantom to demonstrate the existence of the speed artifact when using a commercial US image guidance system to image through layers of simulated body fat, and we compared the results with calculated/predicted values. A general purpose US phantom (speed of sound (SOS) = 1540 m s(-1)) was imaged on a multi-slice CT scanner at a 0.625 mm slice thickness and 0.5 mm x 0.5 mm axial pixel size. Target-simulating wires inside the phantom were contoured and later transferred to the US guidance system. Layers of various thickness (1-8 cm) of commercially manufactured fat-simulating material (SOS = 1435 m s(-1)) were placed on top of the phantom to study the depth-related alignment error. In order to demonstrate that the speed artifact is not caused by adding additional layers on top of the phantom, we repeated these measurements in an identical setup using commercially manufactured tissue-simulating material (SOS = 1540 m s(-1)) for the top layers. For the fat-simulating material used in this study, we observed the magnitude of the depth-related alignment errors resulting from the speed artifact to be 0.7 mm cm(-1) of fat imaged through. The measured alignment errors caused by the speed artifact agreed with the calculated values within one standard deviation for all of the different thicknesses of fat-simulating material studied here. We demonstrated the depth-related alignment error due to the speed artifact when using US image guidance for radiation treatment alignment and note that the presence of fat causes the target to be aliased to a depth greater than it actually is. For typical US guidance systems in use today, this will
Active ultrasound pattern injection system (AUSPIS for interventional tool guidance.

Directory of Open Access Journals (Sweden)

Xiaoyu Guo

Full Text Available Accurate tool tracking is a crucial task that directly affects the safety and effectiveness of many interventional medical procedures. Compared to CT and MRI, ultrasound-based tool tracking has many advantages, including low cost, safety, mobility and ease of use. However, surgical tools are poorly visualized in conventional ultrasound images, thus preventing effective tool tracking and guidance. Existing tracking methods have not yet provided a solution that effectively solves the tool visualization and mid-plane localization accuracy problem and fully meets the clinical requirements. In this paper, we present an active ultrasound tracking and guiding system for interventional tools. The main principle of this system is to establish a bi-directional ultrasound communication between the interventional tool and US imaging machine within the tissue. This method enables the interventional tool to generate an active ultrasound field over the original imaging ultrasound signals. By controlling the timing and amplitude of the active ultrasound field, a virtual pattern can be directly injected into the US machine B mode display. In this work, we introduce the time and frequency modulation, mid-plane detection, and arbitrary pattern injection methods. The implementation of these methods further improves the target visualization and guiding accuracy, and expands the system application beyond simple tool tracking. We performed ex vitro and in vivo experiments, showing significant improvements of tool visualization and accurate localization using different US imaging platforms. An ultrasound image mid-plane detection accuracy of ±0.3 mm and a detectable tissue depth over 8.5 cm was achieved in the experiment. The system performance is tested under different configurations and system parameters. We also report the first experiment of arbitrary pattern injection to the B mode image and its application in accurate tool tracking.
MO-DE-210-07: Investigation of Treatment Interferences of a Novel Robotic Ultrasound Radiotherapy Guidance System with Clinical VMAT Plans for Liver SBRT Patients

Energy Technology Data Exchange (ETDEWEB)

Gong, R [Stanford University, Palo Alto, CA (United States); Bruder, R; Schweikard, A [University of Luebeck, Luebeck, Schleswig-Holstein (Germany); Schlosser, J [SoniTrack Systems Inc., Mountain View, CA (United States); Hristov, D [Stanford University Cancer Center, Palo Alto, CA (United States)

2015-06-15

Purpose: To evaluate the proportion of liver SBRT cases in which robotic ultrasound image guidance concurrent with beam delivery can be deployed without interfering with clinically used VMAT beam configurations. Methods: A simulation environment incorporating LINAC, couch, planning CT, and robotic ultrasound guidance hardware was developed. Virtual placement of the robotic ultrasound hardware was guided by a target visibility map rendered on the CT surface. The map was computed on GPU by using the planning CT to simulate ultrasound propagation and attenuation along rays connecting skin surface points to a rasterized imaging target. The visibility map was validated in a prostate phantom experiment by capturing live ultrasound images of the prostate from different phantom locations. In 20 liver SBRT patients treated with VMAT, the simulation environment was used to place the robotic hardware and ultrasound probe at imaging locations indicated on the visibility map. Imaging targets were either entire PTV (range 5.9–679.5 ml) or entire GTV (range 0.9–343.4 ml). Presence or absence of mechanical collisions with LINAC, couch, and patient body as well as interferences with treated beams were recorded. Results: For PTV targets, robotic ultrasound guidance without mechanical collision was possible in 80% of the cases and guidance without beam interference was possible in 60% of the cases. For the smaller GTV targets, these proportions were 95% and 85% correspondingly. GTV size (1/20), elongated shape (1/20), and depth (1/20) were the main factors limiting the availability of non-interfering imaging positions. Conclusion: This study indicates that for VMAT liver SBRT, robotic ultrasound tracking of a relevant internal target would be possible in 85% of cases while using treatment plans currently deployed in the clinic. With beam re-planning in accordance with the presence of robotic ultrasound guidance, intra-fractional ultrasound guidance may be an option for 95% of the
MO-DE-210-07: Investigation of Treatment Interferences of a Novel Robotic Ultrasound Radiotherapy Guidance System with Clinical VMAT Plans for Liver SBRT Patients

International Nuclear Information System (INIS)

Gong, R; Bruder, R; Schweikard, A; Schlosser, J; Hristov, D

2015-01-01

Purpose: To evaluate the proportion of liver SBRT cases in which robotic ultrasound image guidance concurrent with beam delivery can be deployed without interfering with clinically used VMAT beam configurations. Methods: A simulation environment incorporating LINAC, couch, planning CT, and robotic ultrasound guidance hardware was developed. Virtual placement of the robotic ultrasound hardware was guided by a target visibility map rendered on the CT surface. The map was computed on GPU by using the planning CT to simulate ultrasound propagation and attenuation along rays connecting skin surface points to a rasterized imaging target. The visibility map was validated in a prostate phantom experiment by capturing live ultrasound images of the prostate from different phantom locations. In 20 liver SBRT patients treated with VMAT, the simulation environment was used to place the robotic hardware and ultrasound probe at imaging locations indicated on the visibility map. Imaging targets were either entire PTV (range 5.9–679.5 ml) or entire GTV (range 0.9–343.4 ml). Presence or absence of mechanical collisions with LINAC, couch, and patient body as well as interferences with treated beams were recorded. Results: For PTV targets, robotic ultrasound guidance without mechanical collision was possible in 80% of the cases and guidance without beam interference was possible in 60% of the cases. For the smaller GTV targets, these proportions were 95% and 85% correspondingly. GTV size (1/20), elongated shape (1/20), and depth (1/20) were the main factors limiting the availability of non-interfering imaging positions. Conclusion: This study indicates that for VMAT liver SBRT, robotic ultrasound tracking of a relevant internal target would be possible in 85% of cases while using treatment plans currently deployed in the clinic. With beam re-planning in accordance with the presence of robotic ultrasound guidance, intra-fractional ultrasound guidance may be an option for 95% of the
Smart Ultrasound Remote Guidance Experiment (SURGE) Preliminary Findings

Science.gov (United States)

Hurst, Victor; Dulchavsky, Scott; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Doug

2009-01-01

To date, diagnostic quality ultrasound images were obtained aboard the International Space Station (ISS) using the ultrasound of the Human Research Facility (HRF) rack in the Laboratory module. Through the Advanced Diagnostic Ultrasound in Microgravity (ADUM) and the Braslet-M Occlusion Cuffs (BRASLET SDTO) studies, non-expert ultrasound operators aboard the ISS have performed cardiac, thoracic, abdominal, vascular, ocular, and musculoskeletal ultrasound assessments using remote guidance from ground-based ultrasound experts. With exploration class missions to the lunar and Martian surfaces on the horizon, crew medical officers will necessarily need to operate with greater autonomy given communication delays (round trip times of up to 5 seconds for the Moon and 90 minutes for Mars) and longer periods of communication blackouts (due to orbital constraints of communication assets). The SURGE project explored the feasibility and training requirements of having non-expert ultrasound operators perform autonomous ultrasound assessments in a simulated exploration mission outpost. The project aimed to identify experience, training, and human factors requirements for crew medical officers to perform autonomous ultrasonography. All of these aims pertained to the following risks from the NASA Bioastronautics Road Map: 1) Risk 18: Major Illness and Trauna; 2) Risk 20) Ambulatory Care; 3) Risk 22: Medical Informatics, Technologies, and Support Systems; and 4) Risk 23: Medical Skill Training and Maintenance.
Prototype volumetric ultrasound tomography image guidance system for prone stereotactic partial breast irradiation: proof-of-concept

Science.gov (United States)

Chiu, Tsuicheng D.; Parsons, David; Zhang, Yue; Hrycushko, Brian; Zhao, Bo; Chopra, Rajiv; Kim, Nathan; Spangler, Ann; Rahimi, Asal; Timmerman, Robert; Jiang, Steve B.; Lu, Weiguo; Gu, Xuejun

2018-03-01

Accurate dose delivery in stereotactic partial breast irradiation (S-PBI) is challenging because of the target position uncertainty caused by breast deformation, the target volume changes caused by lumpectomy cavity shrinkage, and the target delineation uncertainty on simulation computed tomography (CT) images caused by poor soft tissue contrast. We have developed a volumetric ultrasound tomography (UST) image guidance system for prone position S-PBI. The system is composed of a novel 3D printed rotation water tank, a patient-specific resin breast immobilization cup, and a 1D array ultrasound transducer. Coronal 2D US images were acquired in 5° increments over a 360° range, and planes were acquired every 2 mm in elevation. A super-compounding technique was used to reconstruct the image volume. The image quality of UST was evaluated with a BB-1 breast phantom and BioZorb surgical marker, and the results revealed that UST offered better soft tissue contrast than CT and similar image quality to MR. In the evaluated plane, the size and location of five embedded objects were measured and compared to MR, which is considered as the ground truth. Objects’ diameters and the distances between objects in UST differ by approximately 1 to 2 mm from those in MR, which showed that UST offers the image quality required for S-PBI. In future work we will develop a robotic system that will be ultimately implemented in the clinic.
Image-guided focused ultrasound ablation of breast cancer: current status, challenges, and future directions

NARCIS (Netherlands)

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

2008-01-01

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

Image guidance improves localization of sonographically occult colorectal liver metastases

Science.gov (United States)

Leung, Universe; Simpson, Amber L.; Adams, Lauryn B.; Jarnagin, William R.; Miga, Michael I.; Kingham, T. Peter

2015-03-01

Assessing the therapeutic benefit of surgical navigation systems is a challenging problem in image-guided surgery. The exact clinical indications for patients that may benefit from these systems is not always clear, particularly for abdominal surgery where image-guidance systems have failed to take hold in the same way as orthopedic and neurosurgical applications. We report interim analysis of a prospective clinical trial for localizing small colorectal liver metastases using the Explorer system (Path Finder Technologies, Nashville, TN). Colorectal liver metastases are small lesions that can be difficult to identify with conventional intraoperative ultrasound due to echogeneity changes in the liver as a result of chemotherapy and other preoperative treatments. Interim analysis with eighteen patients shows that 9 of 15 (60%) of these occult lesions could be detected with image guidance. Image guidance changed intraoperative management in 3 (17%) cases. These results suggest that image guidance is a promising tool for localization of small occult liver metastases and that the indications for image-guided surgery are expanding.
Remotely supported prehospital ultrasound: A feasibility study of real-time image transmission and expert guidance to aid diagnosis in remote and rural communities.

Science.gov (United States)

Eadie, Leila; Mulhern, John; Regan, Luke; Mort, Alasdair; Shannon, Helen; Macaden, Ashish; Wilson, Philip

2017-01-01

Introduction Our aim is to expedite prehospital assessment of remote and rural patients using remotely-supported ultrasound and satellite/cellular communications. In this paradigm, paramedics are remotely-supported ultrasound operators, guided by hospital-based specialists, to record images before receiving diagnostic advice. Technology can support users in areas with little access to medical imaging and suboptimal communications coverage by connecting to multiple cellular networks and/or satellites to stream live ultrasound and audio-video. Methods An ambulance-based demonstrator system captured standard trauma and novel transcranial ultrasound scans from 10 healthy volunteers at 16 locations across the Scottish Highlands. Volunteers underwent brief scanning training before receiving expert guidance via the communications link. Ultrasound images were streamed with an audio/video feed to reviewers for interpretation. Two sessions were transmitted via satellite and 21 used cellular networks. Reviewers rated image and communication quality, and their utility for diagnosis. Transmission latency and bandwidth were recorded, and effects of scanner and reviewer experience were assessed. Results Appropriate views were provided in 94% of the simulated trauma scans. The mean upload rate was 835/150 kbps and mean latency was 114/2072 ms for cellular and satellite networks, respectively. Scanning experience had a significant impact on time to achieve a diagnostic image, and review of offline scans required significantly less time than live-streamed scans. Discussion This prehospital ultrasound system could facilitate early diagnosis and streamlining of treatment pathways for remote emergency patients, being particularly applicable in rural areas worldwide with poor communications infrastructure and extensive transport times.
A region-based segmentation method for ultrasound images in HIFU therapy

International Nuclear Information System (INIS)

Zhang, Dong; Liu, Yu; Yang, Yan; Xu, Menglong; Yan, Yu; Qin, Qianqing

2016-01-01

Purpose: Precisely and efficiently locating a tumor with less manual intervention in ultrasound-guided high-intensity focused ultrasound (HIFU) therapy is one of the keys to guaranteeing the therapeutic result and improving the efficiency of the treatment. The segmentation of ultrasound images has always been difficult due to the influences of speckle, acoustic shadows, and signal attenuation as well as the variety of tumor appearance. The quality of HIFU guidance images is even poorer than that of conventional diagnostic ultrasound images because the ultrasonic probe used for HIFU guidance usually obtains images without making contact with the patient’s body. Therefore, the segmentation becomes more difficult. To solve the segmentation problem of ultrasound guidance image in the treatment planning procedure for HIFU therapy, a novel region-based segmentation method for uterine fibroids in HIFU guidance images is proposed. Methods: Tumor partitioning in HIFU guidance image without manual intervention is achieved by a region-based split-and-merge framework. A new iterative multiple region growing algorithm is proposed to first split the image into homogenous regions (superpixels). The features extracted within these homogenous regions will be more stable than those extracted within the conventional neighborhood of a pixel. The split regions are then merged by a superpixel-based adaptive spectral clustering algorithm. To ensure the superpixels that belong to the same tumor can be clustered together in the merging process, a particular construction strategy for the similarity matrix is adopted for the spectral clustering, and the similarity matrix is constructed by taking advantage of a combination of specifically selected first-order and second-order texture features computed from the gray levels and the gray level co-occurrence matrixes, respectively. The tumor region is picked out automatically from the background regions by an algorithm according to a priori
A region-based segmentation method for ultrasound images in HIFU therapy

Energy Technology Data Exchange (ETDEWEB)

Zhang, Dong, E-mail: dongz@whu.edu.cn; Liu, Yu; Yang, Yan; Xu, Menglong; Yan, Yu [School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Qin, Qianqing [State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430072 (China)

2016-06-15

Purpose: Precisely and efficiently locating a tumor with less manual intervention in ultrasound-guided high-intensity focused ultrasound (HIFU) therapy is one of the keys to guaranteeing the therapeutic result and improving the efficiency of the treatment. The segmentation of ultrasound images has always been difficult due to the influences of speckle, acoustic shadows, and signal attenuation as well as the variety of tumor appearance. The quality of HIFU guidance images is even poorer than that of conventional diagnostic ultrasound images because the ultrasonic probe used for HIFU guidance usually obtains images without making contact with the patient’s body. Therefore, the segmentation becomes more difficult. To solve the segmentation problem of ultrasound guidance image in the treatment planning procedure for HIFU therapy, a novel region-based segmentation method for uterine fibroids in HIFU guidance images is proposed. Methods: Tumor partitioning in HIFU guidance image without manual intervention is achieved by a region-based split-and-merge framework. A new iterative multiple region growing algorithm is proposed to first split the image into homogenous regions (superpixels). The features extracted within these homogenous regions will be more stable than those extracted within the conventional neighborhood of a pixel. The split regions are then merged by a superpixel-based adaptive spectral clustering algorithm. To ensure the superpixels that belong to the same tumor can be clustered together in the merging process, a particular construction strategy for the similarity matrix is adopted for the spectral clustering, and the similarity matrix is constructed by taking advantage of a combination of specifically selected first-order and second-order texture features computed from the gray levels and the gray level co-occurrence matrixes, respectively. The tumor region is picked out automatically from the background regions by an algorithm according to a priori
Visual tracking for multi-modality computer-assisted image guidance

Science.gov (United States)

Basafa, Ehsan; Foroughi, Pezhman; Hossbach, Martin; Bhanushali, Jasmine; Stolka, Philipp

2017-03-01

With optical cameras, many interventional navigation tasks previously relying on EM, optical, or mechanical guidance can be performed robustly, quickly, and conveniently. We developed a family of novel guidance systems based on wide-spectrum cameras and vision algorithms for real-time tracking of interventional instruments and multi-modality markers. These navigation systems support the localization of anatomical targets, support placement of imaging probe and instruments, and provide fusion imaging. The unique architecture - low-cost, miniature, in-hand stereo vision cameras fitted directly to imaging probes - allows for an intuitive workflow that fits a wide variety of specialties such as anesthesiology, interventional radiology, interventional oncology, emergency medicine, urology, and others, many of which see increasing pressure to utilize medical imaging and especially ultrasound, but have yet to develop the requisite skills for reliable success. We developed a modular system, consisting of hardware (the Optical Head containing the mini cameras) and software (components for visual instrument tracking with or without specialized visual features, fully automated marker segmentation from a variety of 3D imaging modalities, visual observation of meshes of widely separated markers, instant automatic registration, and target tracking and guidance on real-time multi-modality fusion views). From these components, we implemented a family of distinct clinical and pre-clinical systems (for combinations of ultrasound, CT, CBCT, and MRI), most of which have international regulatory clearance for clinical use. We present technical and clinical results on phantoms, ex- and in-vivo animals, and patients.
Understanding of percutaneous puncture under guidance of ultrasound in treating peritoneal and perinephritic abscess

International Nuclear Information System (INIS)

Huang Liying; Wang Jiagang

2010-01-01

Objective: To explore the clinical value of percutaneous puncture under guidance of ultrasound in treating peritoneal abscess. Methods: To summarize 68 patients with peritoneal abscess underwent percutaneous puncture under guidance of ultrasound to analyse the method of operation and therapeutic effect. Results: effective power of percutaneous puncture under guidance of ultrasound in treating peritoneal abscess was 96.8%. Conclusion: Percutaneous puncture under guidance of ultrasound in treating peritoneal abscess may avoid injury induced by blinded puncture, with characteristic of easier operation, slighter trauma. higher safety, significant therapeutic effect, and can be spreaded to the clinical application. (authors)
Rapidly-steered single-element ultrasound for real-time volumetric imaging and guidance

Science.gov (United States)

Stauber, Mark; Western, Craig; Solek, Roman; Salisbury, Kenneth; Hristov, Dmitre; Schlosser, Jeffrey

2016-03-01

Volumetric ultrasound (US) imaging has the potential to provide real-time anatomical imaging with high soft-tissue contrast in a variety of diagnostic and therapeutic guidance applications. However, existing volumetric US machines utilize "wobbling" linear phased array or matrix phased array transducers which are costly to manufacture and necessitate bulky external processing units. To drastically reduce cost, improve portability, and reduce footprint, we propose a rapidly-steered single-element volumetric US imaging system. In this paper we explore the feasibility of this system with a proof-of-concept single-element volumetric US imaging device. The device uses a multi-directional raster-scan technique to generate a series of two-dimensional (2D) slices that were reconstructed into three-dimensional (3D) volumes. At 15 cm depth, 90° lateral field of view (FOV), and 20° elevation FOV, the device produced 20-slice volumes at a rate of 0.8 Hz. Imaging performance was evaluated using an US phantom. Spatial resolution was 2.0 mm, 4.7 mm, and 5.0 mm in the axial, lateral, and elevational directions at 7.5 cm. Relative motion of phantom targets were automatically tracked within US volumes with a mean error of -0.3+/-0.3 mm, -0.3+/-0.3 mm, and -0.1+/-0.5 mm in the axial, lateral, and elevational directions, respectively. The device exhibited a mean spatial distortion error of 0.3+/-0.9 mm, 0.4+/-0.7 mm, and -0.3+/-1.9 in the axial, lateral, and elevational directions. With a production cost near $1000, the performance characteristics of the proposed system make it an ideal candidate for diagnostic and image-guided therapy applications where form factor and low cost are paramount.
General Ultrasound Imaging

Medline Plus

Full Text Available ... News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound imaging uses sound waves to produce ... the limitations of General Ultrasound Imaging? What is General Ultrasound Imaging? Ultrasound is safe and painless, and ...
Experimental study on ablating goat liver tissue with ultrasound imaging guided percutaneous irreversible electroporation

Directory of Open Access Journals (Sweden)

Ying LIU

2011-03-01

Full Text Available Objective To investigate the proper method of percutaneous irreversible electroporation(IRE to ablate goat liver tissue under ultrasonic guidance,and observe the features of ultrasound imaging and histological changes.Methods The pulse electric fields(PEFs with permanent duration(100 μs,frequency(1Hz,voltage(2000V and pulses(120 pieces were applied to the electrodes,and the electrodes were placed into goats’ liver under ultrasound guidance through the animal skin to the target area.The treated area was observed by real-time ultrasound scanning,and the histopathological changes were assessed by hematoxylin and eosin(HE staining under light microscope at the time of 0h and 24h after IRE ablation.The circumscribed ablated area was compared with that of finite element modeling(FEM calculation method.Results Ultrasound imaging guidance was accurate in focusing on the target area.Imaging captured by the ultrasound after IRE procedure was quite different from that of the normal liver imaging.Complete hepatic cell death with a sharp demarcation between the ablated zone and the non-ablated zone was well visualized 24 hours after the procedure.Necrospy-based measurement demonstrated a high consistence with FEM-anticipated ablation zones.Conclusion With real-time monitoring by ultrasonography and well-controlled ablation of the target tissue,percutaneous IRE can provide a novel and unique ablative method for cancer treatment.The present paper provides a fundamental experimental work for future studies on clinical application of IRE.
Applicable value of real time interventional ultrasound guidance in family planning reproduction operation

International Nuclear Information System (INIS)

Wu Guoping; Zou Dongfang; Sun Jian; Dong Weihua

2007-01-01

Objective: To determine the clinical value of real time interventional ultrasound guidance in family planning reproduction operation. Methods: Under the guidance of ultrasound monitoring, 522 cases with high risk and difficult uterine operation were undertaken in our department. Results: The abdominal endoscopic contraceptive uterine operation under real time ultrasound monitoring was carried out for 522 cases in 4 years, with successful rates for high risk pregnancy as 287/289 cases, high risk troublesome withdrawal of contraceptive ring as 129/130 cases and puzzling uterine operation as 103/103 cases. The total successful rate reached 99.42%, without uterine rupture and other complications. Conclusion: The former complex, blind and difficult uterine operations turn to be simple, safe and reliable under the guidance of real time ultrasound. (authors)
Ultrasound guidance for internal jugular vein cannulation: Continuing Professional Development.

Science.gov (United States)

Ayoub, Christian; Lavallée, Catherine; Denault, André

2010-05-01

The objective of this continuing professional development module is to describe the role of ultrasound for central venous catheterization and to specify its benefits and limitations. Although ultrasound techniques are useful for all central venous access sites, the focus of this module is on the internal jugular vein approach. In recent years, several studies were published on the benefits of ultrasound use for central venous catheterization. This technique has evolved rapidly due to improvements in the equipment and technology available. Ultrasound helps to detect the anatomical variants of the internal jugular vein. The typical anterolateral position of the internal jugular vein with respect to the carotid is found in only 9-92% of cases. Ultrasound guidance reduces the rate of mechanical, infectious, and thrombotic complications by 57%, and it also reduces the failure rate by 86%. Cost-benefit analyses show that the cost of ultrasound equipment is compensated by the decrease in the expenses associated with the treatment of complications. In this article, we will review the history of ultrasound guidance as well as the reasons that account for its superiority over the classical anatomical landmark technique. We will describe the equipment needed for central venous catheterization as well as the various methods to visualize with ultrasound. To improve patient safety, we recommend the use of ultrasound for central venous catheterization using the internal jugular approach.
Vacuum mammotomy under ultrasound guidance

International Nuclear Information System (INIS)

Luczynska, E.; Kocurek, A.; Pawlik, T.; Aniol, J.; Herman, K.; Skotnicki, P.

2007-01-01

Breast ultrasound is a non-invasive method of breast examination. You can use it also for fine needle biopsy, core needle biopsy, vacuum mammotomy and for placing the '' wire '' before open surgical biopsy. 106 patients (105 women and 1 man) aged 20-71 years (mean age 46.9) were treated in Cancer Institute in Cracow by vacuum mammotomy under ultrasound guidance. The lesions found in ultrasonography were divided into three groups: benign lesions (BI RADS II), ambiguous lesions (BI RADS 0, III and IVa), and suspicious lesions (BI RADS IV B, IV C and V). Then lesions were qualified to vacuum mammotomy. According to USG, fibroadenoma or '' fibroadenoma-like '' lesions were found in 75 women, in 6 women complicated cysts, in 6 women cyst with dense fluid (to differentiate with FA), and in 19 patients undefined lesions. Fibroadenoma was confirmed in histopathology in 74% patients among patients with fibroadenoma or '' fibroadenoma-like '' lesions in ultrasound (in others also benign lesions were found). Among lesions undefined after ultrasound examination (total 27 patients) cancer was confirmed in 6 % (DCIS and IDC). In 6 patients with complicated cysts in ultrasound examination, histopathology confirmed fibroadenoma in 4 women, an intraductal lesion in 1 woman and inflamatory process in 1 woman. Also in 6 women with a dense cyst or fibroadenoma seen in ultrasound, histopathology confirmed fibroadenoma in 3 women and fibrosclerosis in 3 women. Any breast lesions undefined or suspicious after ultrasound examination should be verified. The method of verification or kind of operation of the whole lesion (vacuum mammotomy or '' wire '') depends on many factors, for example: lesion localization; lesion size; BI RADS category. (author)
General Ultrasound Imaging

Medline Plus

Full Text Available ... What are the limitations of General Ultrasound Imaging? What is General Ultrasound Imaging? Ultrasound is safe and ... be heard with every heartbeat. top of page What are some common uses of the procedure? Ultrasound ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... Index A-Z General Ultrasound Ultrasound imaging uses sound waves to produce pictures of the inside of ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...
An improved tracking framework for ultrasound probe localization in image-guided radiosurgery

Directory of Open Access Journals (Sweden)

Ipsen Svenja

2016-09-01

Full Text Available Real-time target localization with ultrasound holds high potential for image guidance and motion compensation in radiosurgery due to its non-invasive image acquisition free from ionizing radiation. However, a two-step localization has to be performed when integrating ultrasound into the existing radiosurgery workflow. In addition to target localization inside the ultrasound volume, the probe itself has to be localized in order to transform the target position into treatment room coordinates. By adapting existing camera calibration tools, we have developed a method to extend the stereoscopic X-ray tracking system of a radiosurgery platform in order to locate objects such as marker geometries with six degrees of freedom. The calibration was performed with 0.1 mm reprojection error. By using the full area of the flat-panel detectors without pre-processing the extended software increased the tracking volume and resolution by up to 80%, substantially improving patient localization and marker detectability. Furthermore, marker-tracking showed sub-millimeter accuracy and rotational errors below 0.1°. This demonstrates that the developed extension framework can accurately localize marker geometries using an integrated X-ray system, establishing the link for the integration of real-time ultrasound image guidance into the existing system.
Treatment of calculus of upper urinary tract with mini-percutaneous nephrolithotomy under ultrasound guidance

International Nuclear Information System (INIS)

Gao Feng; Ye Chunhua; Wang Kanger; Sun Yan

2009-01-01

Objective: To evaluate the feasibility and availability of minimally invasive percutaneous nephrolithotomy (MPCNL) under ultrasound guidance for treatment of calculus of upper urinary tract. Methods: The clinical data of 48 cases with calculus of upper urinary tract undergoing MPCNL were reviewed. Results: In 48 cases, cutaneous-nephric passages were successfully constructed by ultrasound guidance, stone-free rate was 90%. The average operation time was 90 minutes, the average hospitalization was 8 days. No major complications were noted. Conclusion: Under ultrasound guidance, MPCNL with holmium laser is a simply, safe and effective method for treating calculus of upper urinary tract. (authors)
Schwannoma in the porta hepatis - laparoscopic excision under laparoscopic ultrasound guidance.

Science.gov (United States)

Sebastian, Maciej; Sroczyński, Maciej; Donizy, Piotr; Rudnicki, Jerzy

2017-09-01

Schwannomas are usually benign tumors attached to peripheral nerves and are rarely found in the gastrointestinal tract. Schwannomas in the porta hepatis are extremely rare, with only 15 cases described in the literature to date. A 22-year-old female patient presented with colicky upper abdominal pain lasting 3 months. Magnetic resonance imaging of the abdominal cavity revealed a tumor in the porta hepatis. The patient was qualified for laparoscopy. The tumor was totally excised laparoscopically under guidance of laparoscopic ultrasound without intra- or postoperative complications. Postoperative histopathological examination confirmed the porta hepatic schwannoma. The patient recovered uneventfully with very good cosmetic results. In the follow-up period of 5 months we have not observed any abdominal or general health problems. The present case is the first report in the world of laparoscopic ultrasound guided laparoscopic excision of a porta hepatic schwannoma.
Percutaneous drainage with ultrasound guidance in the intensive care unit

International Nuclear Information System (INIS)

Kang, Doo Kyung; Won, Je Hwan; Kim, Jai Keun; Lee, Kwang Hun; Kim, Ji Hyung

2004-01-01

To determine the efficacy and safety of bedside percutaneous drainage procedures with ultrasound guidance in critically ill patients in the intensive care unit (ICU). Sixty five percutaneous drainage procedures performed at the bedside, in 39 ICU patients, were evaluated. All of the procedures were performed with ultrasound guidance alone. The procedures consisted of percutaneous drainage of abdominal (n=35) and pleural (n=27) fluids, percutaneous cholecystostomy (n=2) and percutaneous nephrostomy (n=1). The clinical responses were classified as 'complete response', 'partial response', 'failure' or 'undetermined'. The medical records were reviewed retrospectively to evaluate the clinical response. Technical success was achieved in 64 of the 65 procedures (98.5%). The complication rate was 13.8% (9 cases). There was no immediate procedure-related death or worsening of the clinical condition of the patients. The clinical responses after drainage were 'complete response' in 39 cases (60.9%). 'partial response' in 14 (21.9%), 'failure' in 3 (4.7%), and 'undetermined' in 8 (12.5%). Bedside drainage procedures with ultrasound guidance are effective and safe to perform when patients are too critically ill to be moved from the ICU to the angiography room
Combined photothermal therapy and magneto-motive ultrasound imaging using multifunctional nanoparticles

Science.gov (United States)

Mehrmohammadi, Mohammad; Ma, Li L.; Chen, Yun-Sheng; Qu, Min; Joshi, Pratixa; Chen, Raeanna M.; Johnston, Keith P.; Emelianov, Stanislav

2010-02-01

Photothermal therapy is a laser-based non-invasive technique for cancer treatment. Photothermal therapy can be enhanced by employing metal nanoparticles that absorb the radiant energy from the laser leading to localized thermal damages. Targeting of nanoparticles leads to more efficient uptake and localization of photoabsorbers thus increasing the effectiveness of the treatment. Moreover, efficient targeting can reduce the required dosage of photoabsorbers; thereby reducing the side effects associated with general systematic administration of nanoparticles. Magnetic nanoparticles, due to their small size and response to an external magnetic field gradient have been proposed for targeted drug delivery. In this study, we investigate the applicability of multifunctional nanoparticles (e.g., magneto-plasmonic nanoparticles) and magneto-motive ultrasound imaging for image-guided photothermal therapy. Magneto-motive ultrasound imaging is an ultrasound based imaging technique capable of detecting magnetic nanoparticles indirectly by utilizing a high strength magnetic field to induce motion within the magnetically labeled tissue. The ultrasound imaging is used to detect the internal tissue motion. Due to presence of the magnetic component, the proposed multifunctional nanoparticles along with magneto-motive ultrasound imaging can be used to detect the presence of the photo absorbers. Clearly the higher concentration of magnetic carriers leads to a monotonic increase in magneto-motive ultrasound signal. Thus, magnetomotive ultrasound can determine the presence of the hybrid agents and provide information about their location and concentration. Furthermore, the magneto-motive ultrasound signal can indicate the change in tissue elasticity - a parameter that is expected to change significantly during the photothermal therapy. Therefore, a comprehensive guidance and assessment of the photothermal therapy may be feasible through magneto-motive ultrasound imaging and
Ultrasound Guidance as a Rescue Technique for Peripheral Intravenous Cannulation

National Research Council Canada - National Science Library

Pappas, Nancy L; Michaud, Terese E; Wolbers, Russell M; Steward, James C; Fevurly, Thomas A; Samolitis, Timothy J; Shoneboom, Bruce A; Watts, Dorraine D

2006-01-01

.... Ultrasound guidance has shown efficacy in expediting the cannulation of central veins, but there is limited information on its utility in facilitating cannulation in peripheral veins, particularly...

Ultrasound imaging

International Nuclear Information System (INIS)

Wells, P.N.T.

1983-01-01

Ultrasound is a form of energy which consists of mechanical vibrations the frequencies of which are so high that they are above the range of human hearing. The lower frequency limit of the ultrasonic spectrum may generally be taken to be about 20 kHz. Most biomedical applications of ultrasound employ frequencies in the range 1-15 MHz. At these frequencies, the wavelength is in the range 1.5 - 0.1 mm in soft tissues, and narrow beams of ultrasound can be generated which propagate through such tissues without excessive attenuation. This chapter begins with brief reviews of the physics of diagnostic ultrasound pulse-echo imaging methods and Doppler imaging methods. The remainder of the chapter is a resume of the applications of ultrasonic imaging to physiological measurement
MO-DE-210-03: Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities

International Nuclear Information System (INIS)

Ding, K.

2015-01-01

Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre-treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non-invasive and non-ionizing nature of ultrasound imaging is particularly powerful for intra-fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging. Learning Objectives: Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery. Understanding passive and active robotic approaches to implement ultrasound imaging for intra-fraction monitoring. Understand issues of probe interference with radiotherapy treatment. Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance. The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089
MO-DE-210-03: Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities

Energy Technology Data Exchange (ETDEWEB)

Ding, K. [Johns Hopkins University: Development of Intra-Fraction Soft Tissue Monitoring with Ultrasound Imaging (United States)

2015-06-15

Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre-treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non-invasive and non-ionizing nature of ultrasound imaging is particularly powerful for intra-fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging. Learning Objectives: Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery. Understanding passive and active robotic approaches to implement ultrasound imaging for intra-fraction monitoring. Understand issues of probe interference with radiotherapy treatment. Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance. The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089.
General Ultrasound Imaging

Medline Plus

Full Text Available ... inserted into a man's rectum to view the prostate. Transvaginal ultrasound. The transducer is inserted into a ... Stenting Ultrasound-Guided Breast Biopsy Obstetric Ultrasound Ultrasound - Prostate Biopsies - Overview Images related to General Ultrasound Videos ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... Imaging? Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal imaging technique ... with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes ...
Monitoring and guidance of HIFU beams with dual-mode ultrasound arrays.

Science.gov (United States)

Ballard, John R; Casper, Andrew J; Ebbini, Emad S

2009-01-01

We present experimental results illustrating the unique advantages of dual-mode array (DMUA) systems in monitoring and guidance of high intensity focused ultrasound (HIFU) lesion formation. DMUAs offer a unique paradigm in image-guided surgery; one in which images obtained using the same therapeutic transducer provide feedback for: 1) refocusing the array in the presence of strongly scattering objects, e.g. the ribs, 2) temperature change at the intended location of the HIFU focus, and 3) changes in the echogenicity of the tissue in response to therapeutic HIFU. These forms of feedback have been demonstrated in vitro in preparation for the design and implementation of a real-time system for imaging and therapy with DMUAs. The results clearly demonstrate that DMUA image feedback is spatially accurate and provide sufficient spatial and contrast resolution for identification of high contrast objects like the ribs and significant blood vessels in the path of the HIFU beam.
General Ultrasound Imaging

Medline Plus

Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Conventional ultrasound displays the images in thin, ...
Feasibility of Remote Real-Time Guidance of a Cardiac Examination Performed by Novices Using a Pocket-Sized Ultrasound Device

Directory of Open Access Journals (Sweden)

Tuan V. Mai

2013-01-01

Full Text Available Background. The potential of pocket-sized ultrasound devices (PUDs to improve global healthcare delivery is limited by the lack of a suitable imaging protocol and trained users. Therefore, we investigated the feasibility of performing a brief, evidence-based cardiac limited ultrasound exam (CLUE through wireless guidance of novice users. Methods. Three trainees applied PUDs on 27 subjects while directed by an off-site cardiologist to obtain a CLUE to screen for LV systolic dysfunction (LVSD, LA enlargement (LAE, ultrasound lung comets (ULC+, and elevated CVP (eCVP. Real-time remote audiovisual guidance and interpretation by the cardiologist were performed using the iPhone 4/iPod (FaceTime, Apple, Inc. attached to the PUD and transmitted data wirelessly. Accuracy and technical quality of transmitted images were compared to on-site, gold-standard echo thresholds. Results. Novice versus sonographer imaging yielded technically adequate views in 122/135 (90% versus 130/135 (96% (. CLUE’s combined SN, SP, and ACC were 0.67, 0.96, and 0.90. Technical adequacy (% and accuracy for each abnormality ( were LVSD (85%, 0.93, , LAE (89%, 0.74, , ULC+ (100%, 0.94, , and eCVP (78%, 0.91, . Conclusion. A novice can perform the CLUE using PUD when wirelessly guided by an expert. This method could facilitate PUD use for off-site bedside medical decision making and triaging of patients.
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...
General Ultrasound Imaging

Medline Plus

Full Text Available ... those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in ... ultrasound study may be part of an ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is ...
JJ Stent Removal under Ultrasound Guidance in Women: It is Simple and Safe.

Science.gov (United States)

Amer, Bernard; Gupta, Sandeep; Kanwar, Vijayendra S; Lodh, Bijit; Khumukcham, Somarendra; Akoijam, Kaku Singh

2014-12-01

With the increase in number of patients treated for urological problems with endoscopic procedures, the number of patients with JJ stent is also increasing. The amount of workload thus incurred multiplies, even to the point that, sometimes we waste more time in the operating room removing JJ stents than the actual endourological procedures. Here in our institute, we have devised a very simple and effective way of removing JJ stents in women and also determined the efficacy, safety and cost of JJ stent removal under ultrasound guidance in women in comparison to cystoscopic removal. Two hundred women attending the Department of Urology from July 2012 to July 2013 at RIMS hospital were randomly divided into two arms. One hundred women had their JJ stent removed with cystoscope and another 100 women had their JJ stent removed under ultrasound guidance using simple surgical tools available at the hospital. The primary comparative points were waiting time for operating room appointment date, cost of the procedure, time taken for the procedure, discomfort or pain felt by the patient and urethral injuries. In all the parameters, stent removal under ultrasound guidance was significantly better except for urethral injuries where both the procedures had similar outcomes. We concluded that JJ stent removal under ultrasound guidance in women was simple, effective and safe.
Optimizing MR imaging-guided navigation for focused ultrasound interventions in the brain

Science.gov (United States)

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

2017-03-01

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

Science.gov (United States)

Doyle, Andrea Jane; King, Deirdre M; Browne, Jacinta E

2017-12-01

Ultrasound guided brachytherapy for the treatment of prostate cancer has become a routine treatment option, due to many benefits including patient recovery and dose localisation [1]; however it is not clear whether the standards which govern the image quality for these systems are adequate. Upon review of the recommended standards for ultrasound systems used in prostate brachytherapy procedures, the recommended tests do not appear to be specific to the clinical application of ultrasound guided prostate brachytherapy. Rather they are generic and similar to those recommended for other clinical applications such as general abdominal scanning [2]. Furthermore, there is growing evidence that these tests should be specific to the clinical application [3,4] in order to gain meaningful data about the performance of the system for the application, and also to detect clinically relevant changes in quality control results. An additional problem is that there are no clinically relevant test phantom recommended for the quality assurance of ultrasound systems used in prostate brachytherapy. The image quality for this application of ultrasound needs to be monitored to ensure consistent levels of confidence in the procedure. This paper reviews the currently recommended test guidelines and test phantoms for ultrasound systems used in prostate brachytherapy from the different standard bodies and professional organisations. A critical analysis of those tests which are most reflective of the imaging and guidance tasks undertaken in an ultrasound guided prostate brachytherapy procedure will also be presented to inform the design of a TRUS quality assurance protocol. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
General Ultrasound Imaging

Medline Plus

Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound imaging ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z General Ultrasound Ultrasound ... computer or television monitor. The image is created based on the amplitude (loudness), frequency (pitch) and time ...
Early experience with multiparametric magnetic resonance imaging-targeted biopsies under visual transrectal ultrasound guidance in patients suspicious for prostate cancer undergoing repeated biopsy

DEFF Research Database (Denmark)

Boesen, Lars; Noergaard, Nis; Chabanova, Elizaveta

2015-01-01

OBJECTIVES: The purpose of this study was to investigate the detection rate of prostate cancer (PCa) by multiparametric magnetic resonance imaging-targeted biopsies (mp-MRI-bx) in patients with prior negative transrectal ultrasound biopsy (TRUS-bx) sessions without previous experience of this......-RADS) and Likert classification. All underwent repeated TRUS-bx (10 cores) and mp-MRI-bx under visual TRUS guidance of any mp-MRI-suspicious lesion not targeted by systematic TRUS-bx. RESULTS: PCa was found in 39 out of 83 patients (47%) and mp-MRI identified at least one lesion with some degree of suspicion...
Transvaginal Drainage of Pelvic Abscesses and Collections Using Transabdominal Ultrasound Guidance.

Science.gov (United States)

Ching, Kevin C; Sumkin, Jules H

2015-01-01

Objectives. To evaluate clinical outcomes following transvaginal catheter placement using transabdominal ultrasound guidance for management of pelvic fluid collections. Methods. A retrospective review was performed for all patients who underwent transvaginal catheter drainage of pelvic fluid collections utilizing transabdominal ultrasound guidance between July 2008 and July 2013. 24 consecutive patients were identified and 24 catheters were placed. Results. The mean age of patients was 48.1 years (range = 27-76 y). 88% of collections were postoperative (n = 21), 8% were from pelvic inflammatory disease (n = 2), and 4% were idiopathic (n = 1). Of the 24 patients, 83% of patients (n = 20) had previously undergone a hysterectomy and 1 patient (4%) was pregnant at the time of drainage. The mean volume of initial drainage was 108 mL (range = 5 to 570). Catheters were left in place for an average of 4.3 days (range = 1-17 d). Microbial sampling was performed in all patients with 71% (n = 17) returning a positive culture. All collections were successfully managed percutaneously. There were no technical complications. Conclusions. Transvaginal catheter drainage of pelvic fluid collections using transabdominal ultrasound guidance is a safe and clinically effective procedure. Appropriate percutaneous management can avoid the need for surgery.
General Ultrasound Imaging

Medline Plus

Full Text Available ... testing. image the breasts and guide biopsy of breast cancer ( see the Ultrasound-Guided Breast Biopsy page . diagnose ... Ultrasound is the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn ...
Effect of body mass index on shifts in ultrasound-based image-guided intensity-modulated radiation therapy for abdominal malignancies

International Nuclear Information System (INIS)

Choi, Mehee; Fuller, Clifton D.; Wang, Samuel J.; Siddiqi, Ather; Wong, Adrian; Thomas, Charles R.; Fuss, Martin

2009-01-01

Background and purpose: We investigated whether corrective shifts determined by daily ultrasound-based image-guidance correlate with body mass index (BMI) of patients treated with image-guided intensity-modulated radiation therapy (IG-IMRT) for abdominal malignancies. The utility of daily image-guidance, particularly for patients with BMI > 25.0, is examined. Materials and methods: Total 3162 ultrasound-directed shifts were performed in 86 patients. Direction and magnitude of shifts were correlated with pretreatment BMI. Bivariate statistical analysis and analysis of set-up correction data were performed using systematic and random error calculations. Results: Total 2040 daily alignments were performed. Average 3D vector of set-up correction for all patients was 12.1 mm/fraction. Directional and absolute shifts and 3D vector length were significantly different between BMI cohorts. 3D displacement averaged 4.9 mm/fraction and 6.8mm/fraction for BMI ≤ 25.0 and BMI > 25.0, respectively. Systematic error in all axes and 3D vector was significantly greater for BMI > 25.0. Differences in random error were not statistically significant. Conclusions: Set-up corrections derived from daily ultrasound-based IG-IMRT of abdominal tumors correlated with BMI. Daily image-guidance may improve precision of IMRT delivery with benefits assessed for the entire population, particularly patients with increased habitus. Requisite PTV margins suggested in the absence of daily image-guidance are significantly greater in patients with BMI > 25.0.
A Diagnostic Ultrasound Imaging System

International Nuclear Information System (INIS)

Lee, Seong Woo

1999-01-01

The ability to see the internal organs of the human body in a noninvasive way is a powerful diagnostic tool of modern medicine. Among these imaging modalities such as X-ray, MRI, and ultrasound. MRI and ultrasound are presenting much less risk of undesirable damage of both patient and examiner. In fact, no deleterious effects have been reported as a result of clinical examination by using MRI and ultrasound diagnostic equipment. As a result, their market volume has been rapidly increased. MRI has a good resolution. but there are a few disadvantages such as high price. non-real-time imaging capability. and expensive diagnostic cost. On the other hand, the ultrasound imaging system has inherently poor resolution as compared with X-ray and MRI. In spite of its poor resolution, the ultrasound diagnostic equipment is lower in price and has an ability of real-time imaging as compared with the others. As a result, the ultrasound imaging system has become general and essential modality for imaging the internal organs of human body. In this review various researches and developments to enhance the resolution of the ultrasound images are explained and future trends of the ultrasound imaging technology are described

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

Science.gov (United States)

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

2017-03-01

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

Science.gov (United States)

Guidance that explains the process for getting images approved in One EPA Web microsites and resource directories. includes an appendix that shows examples of what makes some images better than others, how some images convey meaning more than others
Current Brachytherapy Quality Assurance Guidance: Does It Meet the Challenges of Emerging Image-Guided Technologies?

International Nuclear Information System (INIS)

Williamson, Jeffrey F.

2008-01-01

In the past decade, brachytherapy has shifted from the traditional surgical paradigm to more modern three-dimensional image-based planning and delivery approaches. The role of intraoperative and multimodality image-based planning is growing. Published American Association of Physicists in Medicine, American College of Radiology, European Society for Therapeutic Radiology and Oncology, and International Atomic Energy Agency quality assurance (QA) guidelines largely emphasize the QA of planning and delivery devices rather than processes. These protocols have been designed to verify compliance with major performance specifications and are not risk based. With some exceptions, complete and clinically practical guidance exists for sources, QA instrumentation, non-image-based planning systems, applicators, remote afterloading systems, dosimetry, and calibration. Updated guidance is needed for intraoperative imaging systems and image-based planning systems. For non-image-based brachytherapy, the American Association of Physicists in Medicine Task Group reports 56 and 59 provide reasonable guidance on procedure-specific process flow and QA. However, improved guidance is needed even for established procedures such as ultrasound-guided prostate implants. Adaptive replanning in brachytherapy faces unsolved problems similar to that of image-guided adaptive external beam radiotherapy
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... modality for the diagnosis and monitoring of pregnant women and their unborn babies. Ultrasound provides real-time ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... medical test that helps physicians diagnose and treat medical conditions. Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... D images. A Doppler ultrasound study may be part of an ultrasound examination. Doppler ultrasound , also called ... terms of the distance traveled per unit of time, rather than as a color picture. It can ...
Combined ultrasound and MR imaging to guide focused ultrasound therapies in the brain

Science.gov (United States)

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

2013-07-01

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

International Nuclear Information System (INIS)

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

2013-01-01

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

Science.gov (United States)

Zhu, Mengchen; Salcudean, Septimiu E

2011-07-01

In this paper, we propose an interpolation-based method for simulating rigid needles in B-mode ultrasound images in real time. We parameterize the needle B-mode image as a function of needle position and orientation. We collect needle images under various spatial configurations in a water-tank using a needle guidance robot. Then we use multidimensional tensor-product interpolation to simulate images of needles with arbitrary poses and positions using collected images. After further processing, the interpolated needle and seed images are superimposed on top of phantom or tissue image backgrounds. The similarity between the simulated and the real images is measured using a correlation metric. A comparison is also performed with in vivo images obtained during prostate brachytherapy. Our results, carried out for both the convex (transverse plane) and linear (sagittal/para-sagittal plane) arrays of a trans-rectal transducer indicate that our interpolation method produces good results while requiring modest computing resources. The needle simulation method we present can be extended to the simulation of ultrasound images of other wire-like objects. In particular, we have shown that the proposed approach can be used to simulate brachytherapy seeds.
Portable Ultrasound Imaging

DEFF Research Database (Denmark)

di Ianni, Tommaso

This PhD project investigates hardware strategies and imaging methods for hand-held ultrasound systems. The overall idea is to use a wireless ultrasound probe linked to general-purpose mobile devices for the processing and visualization. The approach has the potential to reduce the upfront costs...... beamforming strategies are simulated from a system-level perspective. The quality of the B-mode image is evaluated and the minimum specifications are derived for the design of a portable probe with integrated electronics in-handle. The system is based on a synthetic aperture sequential beamforming approach...... that allows to significantly reduce the data rate between the probe and processing unit. The second part investigates the feasibility of vector flow imaging in a hand-held ultrasound system. Vector flow imaging overcomes the limitations of conventional imaging methods in terms of flow angle compensation...
General Ultrasound Imaging

Medline Plus

Full Text Available ... transducer sends out high-frequency sound waves (that the human ear cannot hear) into the body and then ... ultrasound , there are no known harmful effects on humans. top of page What are the limitations of General Ultrasound Imaging? Ultrasound waves are ...
Evaluating the Learning Curve for Percutaneous Nephrolithotomy under Total Ultrasound Guidance.

Directory of Open Access Journals (Sweden)

Yan Song

Full Text Available To investigate the learning curve of percutaneous nephrolithotomy under total ultrasound guidance.One hundred and twenty consecutive PCNL operations under total ultrasound guidance performed by a novice surgeon in a tertiary referral center were studied. Operations were analyzed in cohorts of 15 to determine when a plateau was reached for the variables such as operation duration, ultrasound screening time, tract dilation time, stone-free rate and complication rate. Comparison was made with the results of a surgeon who had performed more than 1000 PCNLs. Fluoroscopy was not used at all during procedure.The mean operation time dropped from 82.5 min for the first 15 patients to a mean of 64.7 min for cases 46 through 60(P = 0.047. The ultrasound screening time was a peak of 6.4 min in the first 15 cases, whereas it dropped to a mean of 3.9 min for cases 46 through 60(P = 0.01. The tract dilation time dropped from 4.9 min for the first 15 patients to a mean of 3.8 min for cases 46 through 60(P = 0.036. The senior surgeon had a mean operating time, screening time and tract dilation time equivalent to those of the novice surgeon after 60 cases. There was no significant difference in stone free rate and complication rate.The competence of ultrasound guided PCNL is reached after 60 cases with good stone free rate and without major complications.
Children's (Pediatric) Abdominal Ultrasound Imaging

Science.gov (United States)

... Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen Children’s (pediatric) ultrasound imaging of the ... abdomen using ultrasound. View full size with caption Pediatric Content Some imaging tests and treatments have special ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... and treat medical conditions. Conventional ultrasound displays the images in thin, flat sections of the body. Advancements in ultrasound technology include three-dimensional (3- ...
Surgical fiducial segmentation and tracking for pose estimation based on ultrasound B-mode images.

Science.gov (United States)

Lei Chen; Kuo, Nathanael; Aalamifar, Fereshteh; Narrow, David; Coon, Devin; Prince, Jerry; Boctor, Emad M

2016-08-01

Doppler ultrasound is a non-invasive diagnostic tool for the quantitative measurement of blood flow. However, given that it provides velocity data that is dependent on the location and angle of measurement, repeat measurements to detect problems over time may require an expert to return to the same location. We therefore developed an image-guidance system based on ultrasound B-mode images that enables an inexperienced user to position the ultrasound probe at the same site repeatedly in order to acquire a comparable time series of Doppler readings. The system utilizes a bioresorbable fiducial and complementing software composed of the fiducial detection, key points tracking, probe pose estimation, and graphical user interface (GUI) modules. The fiducial is an echogenic marker that is implanted at the surgical site and can be detected and tracked during ultrasound B-mode screening. The key points on the marker can next be used to determine the pose of the ultrasound probe with respect to the marker. The 3D representation of the probe with its position and orientation are then displayed in the GUI for the user guidance. The fiducial detection has been tested on the data sets collected from three animal studies. The pose estimation algorithm was validated by five data sets collected by a UR5 robot. We tested the system on a plastisol phantom and showed that it can detect and track the fiducial marker while displaying the probe pose in real-time.
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen Children’s (pediatric) ultrasound imaging of the ... abdomen using ultrasound. View full size with caption Pediatric Content Some imaging tests and treatments have special ...
Ultrasound enhanced delivery of molecular imaging and therapeutic agents in Alzheimer's disease mouse models.

Directory of Open Access Journals (Sweden)

Scott B Raymond

Full Text Available Alzheimer's disease is a neurodegenerative disorder typified by the accumulation of a small protein, beta-amyloid, which aggregates and is the primary component of amyloid plaques. Many new therapeutic and diagnostic agents for reducing amyloid plaques have limited efficacy in vivo because of poor transport across the blood-brain barrier. Here we demonstrate that low-intensity focused ultrasound with a microbubble contrast agent may be used to transiently disrupt the blood-brain barrier, allowing non-invasive, localized delivery of imaging fluorophores and immunotherapeutics directly to amyloid plaques. We administered intravenous Trypan blue, an amyloid staining red fluorophore, and anti-amyloid antibodies, concurrently with focused ultrasound therapy in plaque-bearing, transgenic mouse models of Alzheimer's disease with amyloid pathology. MRI guidance permitted selective treatment and monitoring of plaque-heavy anatomical regions, such as the hippocampus. Treated brain regions exhibited 16.5+/-5.4-fold increase in Trypan blue fluorescence and 2.7+/-1.2-fold increase in anti-amyloid antibodies that localized to amyloid plaques. Ultrasound-enhanced delivery was consistently reproduced in two different transgenic strains (APPswe:PSEN1dE9, PDAPP, across a large age range (9-26 months, with and without MR guidance, and with little or no tissue damage. Ultrasound-mediated, transient blood-brain barrier disruption allows the delivery of both therapeutic and molecular imaging agents in Alzheimer's mouse models, which should aid pre-clinical drug screening and imaging probe development. Furthermore, this technique may be used to deliver a wide variety of small and large molecules to the brain for imaging and therapy in other neurodegenerative diseases.
Image-guidance for surgical procedures

International Nuclear Information System (INIS)

Peters, Terry M

2006-01-01

Contemporary imaging modalities can now provide the surgeon with high quality three- and four-dimensional images depicting not only normal anatomy and pathology, but also vascularity and function. A key component of image-guided surgery (IGS) is the ability to register multi-modal pre-operative images to each other and to the patient. The other important component of IGS is the ability to track instruments in real time during the procedure and to display them as part of a realistic model of the operative volume. Stereoscopic, virtual- and augmented-reality techniques have been implemented to enhance the visualization and guidance process. For the most part, IGS relies on the assumption that the pre-operatively acquired images used to guide the surgery accurately represent the morphology of the tissue during the procedure. This assumption may not necessarily be valid, and so intra-operative real-time imaging using interventional MRI, ultrasound, video and electrophysiological recordings are often employed to ameliorate this situation. Although IGS is now in extensive routine clinical use in neurosurgery and is gaining ground in other surgical disciplines, there remain many drawbacks that must be overcome before it can be employed in more general minimally-invasive procedures. This review overviews the roots of IGS in neurosurgery, provides examples of its use outside the brain, discusses the infrastructure required for successful implementation of IGS approaches and outlines the challenges that must be overcome for IGS to advance further. (topical review)
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... Imaging? Ultrasound waves are disrupted by air or gas; therefore ultrasound is not an ideal imaging technique ... with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... patient. Because ultrasound images are captured in real-time, they can show the structure and movement of ... vomiting in young infants Because ultrasound provides real-time images, images that are renewed continuously, it also ...

Segmentation of tumor ultrasound image in HIFU therapy based on texture and boundary encoding

International Nuclear Information System (INIS)

Zhang, Dong; Xu, Menglong; Quan, Long; Yang, Yan; Qin, Qianqing; Zhu, Wenbin

2015-01-01

It is crucial in high intensity focused ultrasound (HIFU) therapy to detect the tumor precisely with less manual intervention for enhancing the therapy efficiency. Ultrasound image segmentation becomes a difficult task due to signal attenuation, speckle effect and shadows. This paper presents an unsupervised approach based on texture and boundary encoding customized for ultrasound image segmentation in HIFU therapy. The approach oversegments the ultrasound image into some small regions, which are merged by using the principle of minimum description length (MDL) afterwards. Small regions belonging to the same tumor are clustered as they preserve similar texture features. The mergence is completed by obtaining the shortest coding length from encoding textures and boundaries of these regions in the clustering process. The tumor region is finally selected from merged regions by a proposed algorithm without manual interaction. The performance of the method is tested on 50 uterine fibroid ultrasound images from HIFU guiding transducers. The segmentations are compared with manual delineations to verify its feasibility. The quantitative evaluation with HIFU images shows that the mean true positive of the approach is 93.53%, the mean false positive is 4.06%, the mean similarity is 89.92%, the mean norm Hausdorff distance is 3.62% and the mean norm maximum average distance is 0.57%. The experiments validate that the proposed method can achieve favorable segmentation without manual initialization and effectively handle the poor quality of the ultrasound guidance image in HIFU therapy, which indicates that the approach is applicable in HIFU therapy. (paper)
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... requested the exam. Usually, the referring physician or health care provider will share the results with you. ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... move through vessels. The movement of blood cells causes a change in pitch of the reflected sound ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... need to be returned to the transducer for analysis. Ultrasound has difficulty penetrating bone and, therefore, can ... ultrasound procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Angioplasty and ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... more extensive exams may take up to an hour. When the examination is complete, you may be ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... Ultrasound is the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn ... needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known harmful effects on ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... 3-D) ultrasound that formats the sound wave data into 3-D images. A Doppler ultrasound study ... to do the scanning. The transducer is a small hand-held device that resembles a microphone, attached ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is no ... structure and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... about this beforehand and be made aware of food and drink restrictions that may be needed prior ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... the transducer is pressed against the skin, it directs small pulses of inaudible, high-frequency sound waves ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... 3-D) ultrasound that formats the sound wave data into 3-D images. A Doppler ultrasound study ... at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2018 ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... the patient. Because ultrasound images are captured in real-time, they can show the structure and movement of ... of vomiting in young infants Because ultrasound provides real-time images, images that are renewed continuously, it also ...
Adaptive Beamforming for Medical Ultrasound Imaging

DEFF Research Database (Denmark)

Holfort, Iben Kraglund

This dissertation investigates the application of adaptive beamforming for medical ultrasound imaging. The investigations have been concentrated primarily on the Minimum Variance (MV) beamformer. A broadband implementation of theMV beamformer is described, and simulated data have been used...... to demonstrate the performance. The MV beamformer has been applied to different sets of ultrasound imaging sequences; synthetic aperture ultrasound imaging and plane wave ultrasound imaging. And an approach for applying MV optimized apodization weights on both the transmitting and the receiving apertures...
General Ultrasound Imaging

Medline Plus

Full Text Available ... Ultrasound is safe, noninvasive, and does not use ionizing radiation. This procedure requires little to no special preparation. ... create an image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Children's (pediatric) abdominal ultrasound imaging produces pictures ...
Molecular ultrasound imaging: current status and future directions

International Nuclear Information System (INIS)

Deshpande, N.; Needles, A.; Willmann, J.K.

2010-01-01

Targeted contrast-enhanced ultrasound (molecular ultrasound) is an emerging imaging strategy that combines ultrasound technology with novel molecularly-targeted ultrasound contrast agents for assessing biological processes at the molecular level. Molecular ultrasound contrast agents are nano- or micro-sized particles that are targeted to specific molecular markers by adding high-affinity binding ligands onto the surface of the particles. Following intravenous administration, these targeted ultrasound contrast agents accumulate at tissue sites overexpressing specific molecular markers, thereby enhancing the ultrasound imaging signal. High spatial and temporal resolution, real-time imaging, non-invasiveness, relatively low costs, lack of ionising irradiation and wide availability of ultrasound systems are advantages compared to other molecular imaging modalities. In this article we review current concepts and future directions of molecular ultrasound imaging, including different classes of molecular ultrasound contrast agents, ongoing technical developments of pre-clinical and clinical ultrasound systems, the potential of molecular ultrasound for imaging different diseases at the molecular level, and the translation of molecular ultrasound into the clinic.
Investigation of variability in image acquisition and contouring during 3D ultrasound guidance for partial breast irradiation

International Nuclear Information System (INIS)

Landry, Anthony; Olivotto, Ivo; Beckham, Wayne; Berrang, Tanya; Gagne, Isabelle; Popescu, Carmen; Mitchell, Tracy; Vey, Hazel; Sand, Letricia; Soh, Siew Yan; Wark, Jill

2014-01-01

Three-dimensional ultrasound (3DUS) at simulation compared to 3DUS at treatment is an image guidance option for partial breast irradiation (PBI). This study assessed if user dependence in acquiring and contouring 3DUS (operator variability) contributed to variation in seroma shifts calculated for breast IGRT. Eligible patients met breast criteria for current randomized PBI studies. 5 Operators participated in this study. For each patient, 3 operators were involved in scan acquisitions and 5 were involved in contouring. At CT simulation (CT1), a 3DUS (US1) was performed by a single radiation therapist (RT). 7 to 14 days after CT1 a second CT (CT2) and 3 sequential 3DUS scans (US2a,b,c) were acquired by each of 3 RTs. Seroma shifts, between US1 and US2 scans were calculated by comparing geometric centers of the seromas (centroids). Operator contouring variability was determined by comparing 5 RT’s contours for a single image set. Scanning variability was assessed by comparing shifts between multiple scans acquired at the same time point (US1-US2a,b,c). Shifts in seromas contoured on CT (CT1-CT2) were compared to US data. From an initial 28 patients, 15 had CT visible seromas, met PBI dosimetric constraints, had complete US data, and were analyzed. Operator variability contributed more to the overall variability in seroma localization than the variability associated with multiple scan acquisitions (95% confidence mean uncertainty of 6.2 mm vs. 1.1 mm). The mean standard deviation in seroma shift was user dependent and ranged from 1.7 to 2.9 mm. Mean seroma shifts from simulation to treatment were comparable to CT. Variability in shifts due to different users acquiring and contouring 3DUS for PBI guidance were comparable to CT shifts. Substantial inter-observer effect needs to be considered during clinical implementation of 3DUS IGRT
Effectiveness of Stellate Ganglion Block Under Fuoroscopy or Ultrasound Guidance in Upper Extremity CRPS.

Science.gov (United States)

Imani, Farnad; Hemati, Karim; Rahimzadeh, Poupak; Kazemi, Mohamad Reza; Hejazian, Kokab

2016-01-01

Stellate Ganglion Block (SGB) is an effective technique which may be used to manage upper extremities pain due to Chronic Regional Pain Syndrome (CRPS), in this study we tried to evaluate the effectiveness of this procedure under two different guidance for management of this syndrome. The purpose of this study was to evaluate the effectiveness of ultrsound guide SGB by comparing it with the furoscopy guided SGB in upper extermities CRPS patients in reducing pain & dysfuction of the affected link. Fourteen patients with sympathetic CRPS in upper extremities in a randomized method with block randomization divided in two equal groups (with ultrasound or fluoroscopic guidance). First group was blocked under fluoroscopic guidance and second group blocked under ultrasound guidance. After correct positioning of the needle, a mixture of 5 ml bupivacaine 0.25% and 1 mL of triamcinolone was injected. These data represent no meaningful statistical difference between the two groups in terms of the number of pain attacks before the blocks, a borderline correlation between two groups one week and one month after the block and a significant statistical correlation between two groups three month after the block. These data represent no meaningful statistical difference between the patients of any group in terms of the pain intensity (from one week to six months after block), p-value = 0.61. These data represent a meaningful statistical difference among patients of any group and between the two groups in terms of the pain intensity (before the block until six months after block), p-values were 0.001, 0.031 respectively. According the above mentioned data, in comparison with fluoroscopic guidance, stellate ganglion block under ultrasound guidance is a safe and effective method with lower complication and better improvement in patient's disability indexes.
Ultrasound imaging with a micromotor; Micromotor ni yoru choonpa imaging

Energy Technology Data Exchange (ETDEWEB)

Oshiro, O.; Salimuzzaman, M.; Matani, A.; Chihara, K. [Nara Institute of Science and Technology, Nara (Japan); Asao, M. [Osaka National Hospital, Osaka (Japan)

1998-03-01

This paper describes a new ultrasound intravascular imaging system. In this system, an ultrasound probe consists of a micromotor, an ultrasound reflecting mirror attached with the micromotor and an ultrasound transducer. Ultrasound is scanned radially by a micromotor instead of a rotation transmitting wire and the rotation of the micromotor is performed and controlled by an external magnetic field. This ultrasound imaging system with a micromotor was applied to observe the inside of blood vessels through in vitro experiments. The preliminary results suggest that this system has the sufficient ability to define the blood vessel morphology and that the simple image processing enhances signal-to-noise ratio of the reconstructed image. 12 refs., 5 figs.

Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... radiation. Ultrasound scanning gives a clear picture of soft tissues that do not show up well on x-ray images. Ultrasound provides real-time imaging, making it a good tool for guiding ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... to image by ultrasound because greater amounts of tissue attenuate (weaken) the sound waves as they pass deeper into the body and need to be returned to the transducer for analysis. Ultrasound has difficulty penetrating bone and, therefore, can only see the outer surface ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Children's (pediatric) ... uterus Abdominal ultrasound images can be used to help diagnose appendicitis in children. Except for traumatic injury, ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound images are captured in real-time, they can show the structure and movement of the body's ... kidneys bladder testicles ovaries uterus Abdominal ultrasound images can be used to help diagnose appendicitis in children. ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... women and their unborn babies. Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known harmful effects on humans. top of page What are the ...
Comparison of ultrasound and ultrasound plus nerve stimulator guidance axillary plexus block

International Nuclear Information System (INIS)

Demirelli, G.; Baskan, S.; Karabeyoglu, I.; Aytac, I.; Omek, D.H.; Erdogmus, A.; Baydar, M.

2017-01-01

To evaluate the characteristics of axillary plexus blockade applied using ultrasound only and using ultrasound together with nerve stimulator in patients undergoing planned forearm, wrist or hand surgery. Methods: This randomised, prospective, double-blinded, single-centre study was conducted at Ankara Numune Training and Research Hospital, Ankara, Turkey, from November 2014 to August 2015, and comprised patients undergoing forearm, wrist or hand surgery. Participants were separated into 2 groups. In Group 1, the nerve roots required for the surgical site were located one by one and local anaesthetic was applied separately to each nerve for the block. In Group 2, the vascular nerve bundle was located under ultrasound guidance and a total block was achieved by administering all the local anaesthetic within the nerve sheath. In the operating room, standard monitorisation was applied. Following preparation of the skin, the axillary region nerve roots and branches and vascular structures were observed by examination with a high-frequency ultrasound probe. In both groups, a 22-gauge, 5cm block needle was entered to the axillary region with visualisation of the whole needle on ultrasound and 20ml local anaesthetic of 0.5% bupivacaine was injected. SPSS 19 was used for data analysis. Results: Of the 60 participants, there were 30(50%) in each group. The mean age was 39.1+-15 years in the group 1 which was the ultrasound nerve stimulation group, and 41.5+-14.3 years in group 2. The duration of the procedure was longer in group I than in group 2 (p<0.05). Patient satisfaction values during the procedure were higher in group 2(p<0.05). In the ulnar sensory examination, the values of the patients in group 1 were higher at 10, 15, 20 and 25 minutes (p<0.05). In the median, radial and ulnar motor examination, the values of the patients in group 1were higher at 15 and 20 minutes (p<0.05). Conclusion: Brachial plexus blockade via axillary approach guided by ultrasound offered
Intraoperative endoscopic ultrasound guidance for laparoscopic excision of invisible symptomatic deep intramural myomas.

Science.gov (United States)

Urman, Bulent; Boza, Aysen; Ata, Baris; Aksu, Sertan; Arslan, Tonguc; Taskiran, Cagatay

2018-01-01

The aim of this study was to evaluate the feasibility of intraoperative endoscopic ultrasound guidance for excision of symptomatic deep intramural myomas that are not otherwise visible at laparoscopy. Seventeen patients with symptomatic deep intramural myomas who underwent laparoscopic myomectomy with intraoperative endoscopic ultrasound guidance were followed up and reported. All myomas were removed successfully. The endometrium was breached in one patient. All patients were relieved of their symptoms and three patients presenting with infertility conceived. There were no short- or long-term complications associated with the procedure. One patient who had multiple myomas necessitated intravenous iron treatment prior to discharge. Laparoscopic removal of small symptomatic deep intramural myomas is facilitated by the use of intraoperative endoscopic ultrasound that enables exact localisation and correct placement of the serosal incision. Impact statement What is already known on this subject: When the myoma is symptomatic, compressing the endometrium, does not show serosal protrusion and is not amenable to hysteroscopic resection, laparoscopic surgery may become challenging. What do the results of this study add: The use of intraoperative endoscopic ultrasound under these circumstances may facilitate the procedure by accurate identification of the myoma and correct placement of the serosal incision. What are the implications of these findings for clinical practice and/or further research: Intraoperative ultrasound should be more oftenly used to accurately locate deep intramural myomas to the end of making laparoscopy feasible and possibly decreasing recurrence by facilitating removal of otherwise unidentifiable disease.
Ultrasound/Magnetic Resonance Image Fusion Guided Lumbosacral Plexus Block – A Clinical Study

DEFF Research Database (Denmark)

Strid, JM; Pedersen, Erik Morre; Søballe, Kjeld

2014-01-01

in a double-blinded randomized controlled trial with crossover design. MR datasets will be acquired and uploaded in an advanced US system (Epiq7, Phillips, Amsterdam, Netherlands). All volunteers will receive SSPS blocks with lidocaine added gadolinium contrast guided by US/MR image fusion and by US one week......Background and aims Ultrasound (US) guided lumbosacral plexus block (Supra Sacral Parallel Shift [SSPS]) offers an alternative to general anaesthesia and perioperative analgesia for hip surgery.1 The complex anatomy of the lumbosacral region hampers the accuracy of the block, but it may be improved...... by guidance of US and magnetic resonance (MR) image fusion and real-time 3D electronic needle tip tracking.2 We aim to estimate the effect and the distribution of lidocaine after SSPS guided by US/MR image fusion compared to SSPS guided by ultrasound. Methods Twenty-four healthy volunteers will be included...
Intrauterine photoacoustic and ultrasound imaging probe

Science.gov (United States)

Miranda, Christopher; Barkley, Joel; Smith, Barbara S.

2018-04-01

Intrauterine photoacoustic and ultrasound imaging are probe-based imaging modalities with translational potential for use in detecting endometrial diseases. This deep-tissue imaging probe design allows for the retrofitting of commercially available endometrial sampling curettes. The imaging probe presented here has a 2.92-mm diameter and approximate length of 26 cm, which allows for entry into the human endometrial cavity, making it possible to use photoacoustic imaging and high-resolution ultrasound to characterize the uterus. We demonstrate the imaging probes' ability to provide structural information of an excised pig uterus using ultrasound imaging and detect photoacoustic signals at a radial depth of 1 cm.
Image-guided ultrasound phased arrays are a disruptive technology for non-invasive therapy.

Science.gov (United States)

Hynynen, Kullervo; Jones, Ryan M

2016-09-07

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

Science.gov (United States)

Vaezy, Shahram (Inventor); Held, Robert (Inventor); Sikdar, Siddhartha (Inventor); Managuli, Ravi (Inventor); Zderic, Vesna (Inventor)

2010-01-01

Disclosed herein is a method for obtaining a composite interference-free ultrasound image when non-imaging ultrasound waves would otherwise interfere with ultrasound imaging. A conventional ultrasound imaging system is used to collect frames of ultrasound image data in the presence of non-imaging ultrasound waves, such as high-intensity focused ultrasound (HIFU). The frames are directed to a processor that analyzes the frames to identify portions of the frame that are interference-free. Interference-free portions of a plurality of different ultrasound image frames are combined to generate a single composite interference-free ultrasound image that is displayed to a user. In this approach, a frequency of the non-imaging ultrasound waves is offset relative to a frequency of the ultrasound imaging waves, such that the interference introduced by the non-imaging ultrasound waves appears in a different portion of the frames.
Abdominal ultrasound (image)

Science.gov (United States)

Abdominal ultrasound is a scanning technique used to image the interior of the abdomen. Like the X- ... use high frequency sound waves to produce an image and do not expose the individual to radiation. ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen Children’s (pediatric) ultrasound imaging of ... 30 minutes. top of page What will my child experience during and after the procedure? Ultrasound examinations ...
OSPACS: Ultrasound image management system

Directory of Open Access Journals (Sweden)

Bessant Conrad

2008-06-01

Full Text Available Abstract Background Ultrasound scanning uses the medical imaging format, DICOM, for electronically storing the images and data associated with a particular scan. Large health care facilities typically use a picture archiving and communication system (PACS for storing and retrieving such images. However, these systems are usually not suitable for managing large collections of anonymized ultrasound images gathered during a clinical screening trial. Results We have developed a system enabling the accurate archiving and management of ultrasound images gathered during a clinical screening trial. It is based upon a Windows application utilizing an open-source DICOM image viewer and a relational database. The system automates the bulk import of DICOM files from removable media by cross-validating the patient information against an external database, anonymizing the data as well as the image, and then storing the contents of the file as a field in a database record. These image records may then be retrieved from the database and presented in a tree-view control so that the user can select particular images for display in a DICOM viewer or export them to external media. Conclusion This system provides error-free automation of ultrasound image archiving and management, suitable for use in a clinical trial. An open-source project has been established to promote continued development of the system.
Intrauterine photoacoustic and ultrasound imaging probe.

Science.gov (United States)

Miranda, Christopher; Barkley, Joel; Smith, Barbara

2018-04-01

Intrauterine photoacoustic and ultrasound imaging are probe-based imaging modalities with translational potential for use in detecting endometrial diseases. This deep-tissue imaging probe design allows for the retrofitting of commercially available endometrial sampling curettes. The imaging probe presented here has a 2.92-mm diameter and approximate length of 26 cm, which allows for entry into the human endometrial cavity, making it possible to use photoacoustic imaging and high-resolution ultrasound to characterize the uterus. We demonstrate the imaging probes' ability to provide structural information of an excised pig uterus using ultrasound imaging and detect photoacoustic signals at a radial depth of 1 cm. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).
General Ultrasound Imaging

Medline Plus

Full Text Available ... to-use and less expensive than other imaging methods. Ultrasound imaging is extremely safe and does not ... barium exams, CT scanning , and MRI are the methods of choice in such a setting. Large patients ...
Co-registered photoacoustic, thermoacoustic, and ultrasound mouse imaging

Science.gov (United States)

Reinecke, Daniel R.; Kruger, Robert A.; Lam, Richard B.; DelRio, Stephen P.

2010-02-01

We have constructed and tested a prototype test bed that allows us to form 3D photoacoustic CT images using near-infrared (NIR) irradiation (700 - 900 nm), 3D thermoacoustic CT images using microwave irradiation (434 MHz), and 3D ultrasound images from a commercial ultrasound scanner. The device utilizes a vertically oriented, curved array to capture the photoacoustic and thermoacoustic data. In addition, an 8-MHz linear array fixed in a horizontal position provides the ultrasound data. The photoacoustic and thermoacoustic data sets are co-registered exactly because they use the same detector. The ultrasound data set requires only simple corrections to co-register its images. The photoacoustic, thermoacoustic, and ultrasound images of mouse anatomy reveal complementary anatomic information as they exploit different contrast mechanisms. The thermoacoustic images differentiate between muscle, fat and bone. The photoacoustic images reveal the hemoglobin distribution, which is localized predominantly in the vascular space. The ultrasound images provide detailed information about the bony structures. Superposition of all three images onto a co-registered hybrid image shows the potential of a trimodal photoacoustic-thermoacoustic-ultrasound small-animal imaging system.
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... is Abdominal Ultrasound Imaging? What are some common uses of the procedure? How should we prepare for an ultrasound exam? What does the ultrasound equipment look like? How does the procedure work? How is the procedure performed? What will my ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... waves from passing into your body. The sonographer (ultrasound technologist) or radiologist then places the transducer on the skin in various locations, sweeping over the area of interest or angling the ... ultrasound images are reviewed. An ultrasound examination is usually ...
MO-DE-210-06: Development of a Supercompounded 3D Volumetric Ultrasound Image Guidance System for Prone Accelerated Partial Breast Irradiation (APBI)

Energy Technology Data Exchange (ETDEWEB)

Chiu, T; Hrycushko, B; Zhao, B; Jiang, S; Gu, X [UT Southwestern Medical Center, Dallas, TX (United States)

2015-06-15

Purpose: For early-stage breast cancer, accelerated partial breast irradiation (APBI) is a cost-effective breast-conserving treatment. Irradiation in a prone position can mitigate respiratory induced breast movement and achieve maximal sparing of heart and lung tissues. However, accurate dose delivery is challenging due to breast deformation and lumpectomy cavity shrinkage. We propose a 3D volumetric ultrasound (US) image guidance system for accurate prone APBI Methods: The designed system, set beneath the prone breast board, consists of a water container, an US scanner, and a two-layer breast immobilization cup. The outer layer of the breast cup forms the inner wall of water container while the inner layer is attached to patient breast directly to immobilization. The US transducer scans is attached to the outer-layer of breast cup at the dent of water container. Rotational US scans in a transverse plane are achieved by simultaneously rotating water container and transducer, and multiple transverse scanning forms a 3D scan. A supercompounding-technique-based volumetric US reconstruction algorithm is developed for 3D image reconstruction. The performance of the designed system is evaluated with two custom-made gelatin phantoms containing several cylindrical inserts filled in with water (11% reflection coefficient between materials). One phantom is designed for positioning evaluation while the other is for scaling assessment. Results: In the positioning evaluation phantom, the central distances between the inserts are 15, 20, 30 and 40 mm. The distances on reconstructed images differ by −0.19, −0.65, −0.11 and −1.67 mm, respectively. In the scaling evaluation phantom, inserts are 12.7, 19.05, 25.40 and 31.75 mm in diameter. Measured inserts’ sizes on images differed by 0.23, 0.19, −0.1 and 0.22 mm, respectively. Conclusion: The phantom evaluation results show that the developed 3D volumetric US system can accurately localize target position and determine

The vision guidance and image processing of AGV

Science.gov (United States)

Feng, Tongqing; Jiao, Bin

2017-08-01

Firstly, the principle of AGV vision guidance is introduced and the deviation and deflection angle are measured by image coordinate system. The visual guidance image processing platform is introduced. In view of the fact that the AGV guidance image contains more noise, the image has already been smoothed by a statistical sorting. By using AGV sampling way to obtain image guidance, because the image has the best and different threshold segmentation points. In view of this situation, the method of two-dimensional maximum entropy image segmentation is used to solve the problem. We extract the foreground image in the target band by calculating the contour area method and obtain the centre line with the least square fitting algorithm. With the help of image and physical coordinates, we can obtain the guidance information.
Passive cavitation imaging with ultrasound arrays.

Science.gov (United States)

Salgaonkar, Vasant A; Datta, Saurabh; Holland, Christy K; Mast, T Douglas

2009-12-01

A method is presented for passive imaging of cavitational acoustic emissions using an ultrasound array, with potential application in real-time monitoring of ultrasound ablation. To create such images, microbubble emissions were passively sensed by an imaging array and dynamically focused at multiple depths. In this paper, an analytic expression for a passive image is obtained by solving the Rayleigh-Sommerfield integral, under the Fresnel approximation, and passive images were simulated. A 192-element array was used to create passive images, in real time, from 520-kHz ultrasound scattered by a 1-mm steel wire. Azimuthal positions of this target were accurately estimated from the passive images. Next, stable and inertial cavitation was passively imaged in saline solution sonicated at 520 kHz. Bubble clusters formed in the saline samples were consistently located on both passive images and B-scans. Passive images were also created using broadband emissions from bovine liver sonicated at 2.2 MHz. Agreement was found between the images and source beam shape, indicating an ability to map therapeutic ultrasound beams in situ. The relation between these broadband emissions, sonication amplitude, and exposure conditions are discussed.
High definition ultrasound imaging for battlefield medical applications

Energy Technology Data Exchange (ETDEWEB)

Kwok, K.S.; Morimoto, A.K.; Kozlowski, D.M.; Krumm, J.C.; Dickey, F.M. [Sandia National Labs., Albuquerque, NM (United States); Rogers, B; Walsh, N. [Texas Univ. Health Science Center, San Antonio, TX (United States)

1996-06-23

A team has developed an improved resolution ultrasound system for low cost diagnostics. This paper describes the development of an ultrasound based imaging system capable of generating 3D images showing surface and subsurface tissue and bone structures. We include results of a comparative study between images obtained from X-Ray Computed Tomography (CT) and ultrasound. We found that the quality of ultrasound images compares favorably with those from CT. Volumetric and surface data extracted from these images were within 7% of the range between ultrasound and CT scans. We also include images of porcine abdominal scans from two different sets of animal trials.
General Ultrasound Imaging

Medline Plus

Full Text Available ... do not use ionizing radiation (as used in x-rays ), thus there is no radiation exposure to the ... tissues that do not show up well on x-ray images. Ultrasound is the preferred imaging modality for ...
Ultrasound and MR imaging of diabetic mastopathy

International Nuclear Information System (INIS)

Wong, K.T.; Tse, G.M.K.; Yang, W.T.

2002-01-01

AIM: To review the imaging findings of diabetic mastopathy, and document the colour flow ultrasound and MR imaging features in this benign condition. MATERIALS AND METHODS: Diabetic mastopathy was clinically and histologically diagnosed in eight lesions in six women. All six women underwent conventional mammography and high frequency grey-scale ultrasound. Colour flow ultrasound was performed additionally in six lesions in four women and MR imaging in four lesions in three women before biopsy. The imaging findings were reviewed and correlated with final histological diagnosis. RESULTS: Mammography showed regional asymmetric increased opacity with ill-defined margins in all lesions. A heterogeneously hypoechoic mass with ill-defined margins was identified on high frequency grey-scale ultrasound in all lesions. Marked posterior acoustic shadowing was present in seven of eight (88%) lesions. Six lesions interrogated with colour flow ultrasound showed absence of Doppler signal. MR imaging in three women revealed non-specific stromal enhancement. CONCLUSION: Diabetic mastopathy shows absence of Doppler signal on colour flow ultrasound and non-specific stromal enhancement on MR imaging. Wong K.T. et al. (2002)
Image processing in medical ultrasound

DEFF Research Database (Denmark)

Hemmsen, Martin Christian

This Ph.D project addresses image processing in medical ultrasound and seeks to achieve two major scientific goals: First to develop an understanding of the most significant factors influencing image quality in medical ultrasound, and secondly to use this knowledge to develop image processing...... multiple imaging setups. This makes the system well suited for development of new processing methods and for clinical evaluations, where acquisition of the exact same scan location for multiple methods is important. The second project addressed implementation, development and evaluation of SASB using...... methods for enhancing the diagnostic value of medical ultrasound. The project is an industrial Ph.D project co-sponsored by BK Medical ApS., with the commercial goal to improve the image quality of BK Medicals scanners. Currently BK Medical employ a simple conventional delay-and-sum beamformer to generate...
Endoluminal ultrasound applicator with an integrated RF coil for high-resolution magnetic resonance imaging-guided high-intensity contact ultrasound thermotherapy

International Nuclear Information System (INIS)

Rata, Mihaela; Salomir, Rares; Lafon, Cyril; Umathum, Reiner; Jenne, Juergen; Bock, Michael; Cotton, Francois

2008-01-01

High-intensity contact ultrasound (HICU) under MRI guidance may provide minimally invasive treatment of endocavitary digestive tumors in the esophagus, colon or rectum. In this study, a miniature receive-only coil was integrated into an endoscopic ultrasound applicator to offer high-resolution MRI guidance of thermotherapy. A cylindrical plastic support with an incorporated single element flat transducer (9.45 MHz, water cooling tip) was made and equipped with a rectangular RF loop coil surrounding the active element. The integrated coil provided significantly higher sensitivity than a four-element extracorporeal phased array coil, and the standard deviation of the MR thermometry (SDT) improved up to a factor of 7 at 10 mm depth in tissue. High-resolution morphological images (T1w-TFE and IR-T1w-TSE with a voxel size of 0.25 x 0.25 x 3 mm 3 ) and accurate thermometry data (the PRFS method with a voxel size of 0.5 x 0.5 x 5 mm 3 , 2.2 s/image, 0.3 deg. C voxel-wise SDT) were acquired in an ex vivo esophagus sample, on a clinical 1.5T scanner. The endoscopic device was actively operated under automatic temperature control, demonstrating a high level of accuracy (1.7% standard deviation, 1.1% error of mean value), which indicates that this technology may be suitable for HICU therapy of endoluminal cancer.
Endoluminal ultrasound applicator with an integrated RF coil for high-resolution magnetic resonance imaging-guided high-intensity contact ultrasound thermotherapy

Science.gov (United States)

Rata, Mihaela; Salomir, Rares; Umathum, Reiner; Jenne, Jürgen; Lafon, Cyril; Cotton, François; Bock, Michael

2008-11-01

High-intensity contact ultrasound (HICU) under MRI guidance may provide minimally invasive treatment of endocavitary digestive tumors in the esophagus, colon or rectum. In this study, a miniature receive-only coil was integrated into an endoscopic ultrasound applicator to offer high-resolution MRI guidance of thermotherapy. A cylindrical plastic support with an incorporated single element flat transducer (9.45 MHz, water cooling tip) was made and equipped with a rectangular RF loop coil surrounding the active element. The integrated coil provided significantly higher sensitivity than a four-element extracorporeal phased array coil, and the standard deviation of the MR thermometry (SDT) improved up to a factor of 7 at 10 mm depth in tissue. High-resolution morphological images (T1w-TFE and IR-T1w-TSE with a voxel size of 0.25 × 0.25 × 3 mm3) and accurate thermometry data (the PRFS method with a voxel size of 0.5 × 0.5 × 5 mm3, 2.2 s/image, 0.3 °C voxel-wise SDT) were acquired in an ex vivo esophagus sample, on a clinical 1.5T scanner. The endoscopic device was actively operated under automatic temperature control, demonstrating a high level of accuracy (1.7% standard deviation, 1.1% error of mean value), which indicates that this technology may be suitable for HICU therapy of endoluminal cancer.
MR imaging guidance and monitoring of focal thermotherapies. A review

International Nuclear Information System (INIS)

Mueller-Lisse, U.G.; California Univ., San Francisco, CA; Heuck, A.F.

1998-01-01

Minimally invasive thermotherapies for focal tissue destruction on the basis of laser-, microwave-, focused ultrasound-, or cryogeninduced changes of tissue temperature represent an alternative to surgical tissue ablation, particularly in the treatment of tumors. The thermotherapy modalities listed necessitate indirect guidance and monitoring, since they often do not lend themselves to immediate visual control. In the brain, in head and neck tumors, in the liver, and in the prostate, MRI reliably and accurately delineates both the positions of interstitial thermotherapy applicators and - in contrast-enhanced, T1-weighted images - the perfusion defects in tissue necrosis induced by thermotherapy. The transfer of results of in-vitro and in-vivo model studies to assess interstitial temperature and lesion development during thermotherapy to the actual treatment of patients, however, is still in an initial phase. Further development of both rapid MRI sequences and MRI scanners suited for interventions will show how far treatment systems and guidance systems can be adapted to one another. (orig.) [de
Image-guided Navigation of Single-element Focused Ultrasound Transducer

Science.gov (United States)

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

2014-01-01

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

Medline Plus

Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...
A needle guidance system for biopsy and therapy using two-dimensional ultrasound

International Nuclear Information System (INIS)

Bluvol, Nathan; Sheikh, Allison; Kornecki, Anat; Del Rey Fernandez, David; Downey, Donal; Fenster, Aaron

2008-01-01

Image-guided needle biopsies are currently used to provide a definitive diagnosis of breast cancer; however, difficulties in tumor targeting exist as the ultrasound (United States) scan plane and biopsy needle must remain coplanar throughout the procedure to display the actual needle tip position. The additional time associated with aligning and maintaining this coplanar relationship results in increased patient discomfort. Biopsy procedural efficiency is further hindered since needle pathway interpretation is often difficult, especially for needle insertions at large depths that usually require multiple reinsertions. The authors developed a system that would increase the speed and accuracy of current breast biopsy procedures using readily available two-dimensional (2D) US technology. This system is composed of a passive articulated mechanical arm that attaches to a 2D US transducer. The arm is connected to a computer through custom electronics and software, which were developed as an interface for tracking the positioning of the mechanical components in real time. The arm couples to the biopsy needle and provides visual guidance for the physician performing the procedure in the form of a real-time projected needle pathway overlay on an US image of the breast. An agar test phantom, with stainless steel targets interspersed randomly throughout, was used to validate needle trajectory positioning accuracy. The biopsy needle was guided by both the software and hardware components to the targets. The phantom, with the needle inserted and device decoupled, was placed in an x-ray stereotactic mammography (SM) machine. The needle trajectory and bead target locations were determined in three dimensions from the SM images. Results indicated a mean needle trajectory accuracy error of 0.75±0.42 mm. This is adequate to sample lesions that are <2 mm in diameter. Chicken tissue test phantoms were used to compare core needle biopsy procedure times between experienced radiologists
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... imaging produces pictures of the internal organs and blood vessels located within a child's abdomen. A Doppler ultrasound study may be part of a child's abdominal ultrasound ...
Transrectal ultrasound imaging and prostate cancer

NARCIS (Netherlands)

Goossen, Tjerk; Wijkstra, Hessel

2003-01-01

Prostate cancer is one of the most important causes of death from cancer in men. Ultrasound imaging is frequently used in the diagnosis of prostate cancer. This paper presents an overview of currently available ultrasound imaging techniques. The underlying principles and methods are discussed
General Ultrasound Imaging

Medline Plus

Full Text Available ... internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...
Ultrasound guidance to perform intra-articular injection of gadolinium-based contrast material for magnetic resonance arthrography as an alternative to fluoroscopy: the time is now

Energy Technology Data Exchange (ETDEWEB)

Messina, Carmelo [Universita degli Studi di Milano, Scuola di Specializzazione in Radiodiagnostica, Milano (Italy); Banfi, Giuseppe [IRCCS Istituto Ortopedico Galeazzi, Milano (Italy); Universita Vita-Salute San Raffaele, Milano (Italy); Aliprandi, Alberto [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); Mauri, Giovanni [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); Istituto Europeo di Oncologia, Unita di Radiologia Interventistica, Milano (Italy); Secchi, Francesco; Sardanelli, Francesco; Sconfienza, Luca Maria [Universita degli Studi di Milano, Dipartimento di Scienze Biomediche per la Salute, Milano (Italy); IRCCS Policlinico San Donato, Servizio di Radiologia, San Donato, Milanese (Italy)

2016-05-15

Magnetic resonance (MR) imaging has been definitively established as the reference standard in the evaluation of joints in the body. Similarly, magnetic resonance arthrography has emerged as a technique that has been proven to increase significantly the diagnostic performance if compared with conventional MR imaging, especially when dealing with fibrocartilage and articular cartilage abnormalities. Diluted gadolinium can be injected in the joint space using different approaches: under palpation using anatomic landmarks or using an imaging guidance, such as fluoroscopy, computed tomography, or ultrasound. Fluoroscopy has been traditionally used, but the involvement of ionizing radiation should represent a remarkable limitation of this modality. Conversely, ultrasound has emerged as a feasible, cheap, quick, and radiation-free modality that can be used to inject joints, with comparable accuracy of fluoroscopy. In the present paper, we discuss the advantages and disadvantages of using fluoroscopy or ultrasound in injecting gadolinium-based contrast agents in joints to perform magnetic resonance arthrography, also in view of the new EuroSAFE Imaging initiative promoted by the European Society of Radiology and the recent updates to the European Atomic Energy Community 2013/59 directive on the medical use of ionizing radiation. (orig.)
Resolution enhancement in medical ultrasound imaging.

Science.gov (United States)

Ploquin, Marie; Basarab, Adrian; Kouamé, Denis

2015-01-01

Image resolution enhancement is a problem of considerable interest in all medical imaging modalities. Unlike general purpose imaging or video processing, for a very long time, medical image resolution enhancement has been based on optimization of the imaging devices. Although some recent works purport to deal with image postprocessing, much remains to be done regarding medical image enhancement via postprocessing, especially in ultrasound imaging. We face a resolution improvement issue in the case of medical ultrasound imaging. We propose to investigate this problem using multidimensional autoregressive (AR) models. Noting that the estimation of the envelope of an ultrasound radio frequency (RF) signal is very similar to the estimation of classical Fourier-based power spectrum estimation, we theoretically show that a domain change and a multidimensional AR model can be used to achieve super-resolution in ultrasound imaging provided the order is estimated correctly. Here, this is done by means of a technique that simultaneously estimates the order and the parameters of a multidimensional model using relevant regression matrix factorization. Doing so, the proposed method specifically fits ultrasound imaging and provides an estimated envelope. Moreover, an expression that links the theoretical image resolution to both the image acquisition features (such as the point spread function) and a postprocessing feature (the AR model) order is derived. The overall contribution of this work is threefold. First, it allows for automatic resolution improvement. Through a simple model and without any specific manual algorithmic parameter tuning, as is used in common methods, the proposed technique simply and exclusively uses the ultrasound RF signal as input and provides the improved B-mode as output. Second, it allows for the a priori prediction of the improvement in resolution via the knowledge of the parametric model order before actual processing. Finally, to achieve the
General Ultrasound Imaging

Medline Plus

Full Text Available ... General ultrasound procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... abdomen is a safe, noninvasive test that uses sound waves to produce a clear picture of the ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... requested the exam. Usually, the referring physician or health care provider will share the results with you. ...

Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... children. Except for traumatic injury, appendicitis is the most common reason for emergency abdominal surgery. Ultrasound imaging ... of page How is the procedure performed? For most ultrasound exams, you will be positioned lying face- ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... and produces pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound ... from the probe through the gel into the body. The transducer collects the sounds that bounce back ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... placement and fluid drainage for diagnosis and/or relief of patient discomfort. Doppler ultrasound images can help ... tenderness, your child may feel pressure or minor pain from the procedure. If a Doppler ultrasound study ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is no ... structure and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... the best way to see if treatment is working or if a finding is stable or changed ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound. top of page How does the procedure work? Ultrasound imaging is based on the same principles ... the transducer is pressed against the skin, it directs small pulses of inaudible, high-frequency sound waves ...
Signal Processing in Medical Ultrasound B-mode Imaging

International Nuclear Information System (INIS)

Song, Tai Kyong

2000-01-01

Ultrasonic imaging is the most widely used modality among modern imaging device for medical diagnosis and the system performance has been improved dramatically since early 90's due to the rapid advances in DSP performance and VLSI technology that made it possible to employ more sophisticated algorithms. This paper describes 'main stream' digital signal processing functions along with the associated implementation considerations in modern medical ultrasound imaging systems. Topics covered include signal processing methods for resolution improvement, ultrasound imaging system architectures, roles and necessity of the applications of DSP and VLSI technology in the development of the medical ultrasound imaging systems, and array signal processing techniques for ultrasound focusing
Computer model for harmonic ultrasound imaging.

Science.gov (United States)

Li, Y; Zagzebski, J A

2000-01-01

Harmonic ultrasound imaging has received great attention from ultrasound scanner manufacturers and researchers. In this paper, we present a computer model that can generate realistic harmonic images. In this model, the incident ultrasound is modeled after the "KZK" equation, and the echo signal is modeled using linear propagation theory because the echo signal is much weaker than the incident pulse. Both time domain and frequency domain numerical solutions to the "KZK" equation were studied. Realistic harmonic images of spherical lesion phantoms were generated for scans by a circular transducer. This model can be a very useful tool for studying the harmonic buildup and dissipation processes in a nonlinear medium, and it can be used to investigate a wide variety of topics related to B-mode harmonic imaging.
Holistic ultrasound in trauma: An update.

Science.gov (United States)

Saranteas, Theodosios; Mavrogenis, Andreas F

2016-10-01

Holistic ultrasound is a total body examination using an ultrasound device aiming to achieve immediate patient care and decision making. In the setting of trauma, it is one of the most fundamental components of care of the injured patients. Ground-breaking imaging software allows physicians to examine various organs thoroughly, recognize imaging signs early, and potentially foresee the onset or the possible outcome of certain types of injuries. Holistic ultrasound can be performed on a routine basis at the bedside of the patients, at admission and during the perioperative period. Trauma care physicians should be aware of the diagnostic and guidance benefits of ultrasound and should receive appropriate training for the optimal management of their patients. In this paper, the findings of holistic ultrasound in trauma patients are presented, with emphasis on the lungs, heart, cerebral circulation, abdomen, and airway. Additionally, the benefits of ultrasound imaging in interventional anaesthesia techniques such as ultrasound-guided peripheral nerve blocks and central vein catheterization are described. Copyright © 2016 Elsevier Ltd. All rights reserved.
Fast and Automatic Ultrasound Simulation from CT Images

Directory of Open Access Journals (Sweden)

Weijian Cong

2013-01-01

Full Text Available Ultrasound is currently widely used in clinical diagnosis because of its fast and safe imaging principles. As the anatomical structures present in an ultrasound image are not as clear as CT or MRI. Physicians usually need advance clinical knowledge and experience to distinguish diseased tissues. Fast simulation of ultrasound provides a cost-effective way for the training and correlation of ultrasound and the anatomic structures. In this paper, a novel method is proposed for fast simulation of ultrasound from a CT image. A multiscale method is developed to enhance tubular structures so as to simulate the blood flow. The acoustic response of common tissues is generated by weighted integration of adjacent regions on the ultrasound propagation path in the CT image, from which parameters, including attenuation, reflection, scattering, and noise, are estimated simultaneously. The thin-plate spline interpolation method is employed to transform the simulation image between polar and rectangular coordinate systems. The Kaiser window function is utilized to produce integration and radial blurring effects of multiple transducer elements. Experimental results show that the developed method is very fast and effective, allowing realistic ultrasound to be fast generated. Given that the developed method is fully automatic, it can be utilized for ultrasound guided navigation in clinical practice and for training purpose.
Application of image guidance in pituitary surgery

Science.gov (United States)

de Lara, Danielle; Filho, Leo F. S. Ditzel; Prevedello, Daniel M.; Otto, Bradley A.; Carrau, Ricardo L.

2012-01-01

Background: Surgical treatment of pituitary pathologies has evolved along the years, adding safety and decreasing morbidity related to the procedure. Advances in the field of radiology, coupled with stereotactic technology and computer modeling, have culminated in the contemporary and widespread use of image guidance systems, as we know them today. Image guidance navigation has become a frequently used technology that provides continuous three-dimensional information for the accurate performance of neurosurgical procedures. We present a discussion about the application of image guidance in pituitary surgeries. Methods: Major indications for image guidance neuronavigation application in pituitary surgery are presented and demonstrated with illustrative cases. Limitations of this technology are also presented. Results: Patients presenting a history of previous transsphenoidal surgeries, anatomical variances of the sphenoid sinus, tumors with a close relation to the internal carotid arteries, and extrasellar tumors are the most important indications for image guidance in pituitary surgeries. The high cost of the equipment, increased time of surgery due to setup time, and registration and the need of specific training for the operating room personnel could be pointed as limitations of this technology. Conclusion: Intraoperative image guidance systems provide real-time images, increasing surgical accuracy and enabling safe, minimally invasive interventions. However, the use of intraoperative navigation is not a replacement for surgical experience and a systematic knowledge of regional anatomy. It must be recognized as a tool by which the neurosurgeon can reduce the risk associated with surgical approach and treatment of pituitary pathologies. PMID:22826819
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... within your child’s abdomen. Ultrasound does not use ionizing radiation, has no known harmful effects, and is particularly ... create an image. Ultrasound examinations do not use ionizing radiation (as used in x-rays ), thus there is ...
Ultrasound imaging using coded signals

DEFF Research Database (Denmark)

Misaridis, Athanasios

Modulated (or coded) excitation signals can potentially improve the quality and increase the frame rate in medical ultrasound scanners. The aim of this dissertation is to investigate systematically the applicability of modulated signals in medical ultrasound imaging and to suggest appropriate...... methods for coded imaging, with the goal of making better anatomic and flow images and three-dimensional images. On the first stage, it investigates techniques for doing high-resolution coded imaging with improved signal-to-noise ratio compared to conventional imaging. Subsequently it investigates how...... coded excitation can be used for increasing the frame rate. The work includes both simulated results using Field II, and experimental results based on measurements on phantoms as well as clinical images. Initially a mathematical foundation of signal modulation is given. Pulse compression based...
General Ultrasound Imaging

Medline Plus

Full Text Available ... and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...
3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

Energy Technology Data Exchange (ETDEWEB)

Morimoto, A.K.; Bow, W.J.; Strong, D.S. [and others

1995-06-01

The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.
Preoperative magnetic resonance and intraoperative ultrasound fusion imaging for real-time neuronavigation in brain tumor surgery.

Science.gov (United States)

Prada, F; Del Bene, M; Mattei, L; Lodigiani, L; DeBeni, S; Kolev, V; Vetrano, I; Solbiati, L; Sakas, G; DiMeco, F

2015-04-01

Brain shift and tissue deformation during surgery for intracranial lesions are the main actual limitations of neuro-navigation (NN), which currently relies mainly on preoperative imaging. Ultrasound (US), being a real-time imaging modality, is becoming progressively more widespread during neurosurgical procedures, but most neurosurgeons, trained on axial computed tomography (CT) and magnetic resonance imaging (MRI) slices, lack specific US training and have difficulties recognizing anatomic structures with the same confidence as in preoperative imaging. Therefore real-time intraoperative fusion imaging (FI) between preoperative imaging and intraoperative ultrasound (ioUS) for virtual navigation (VN) is highly desirable. We describe our procedure for real-time navigation during surgery for different cerebral lesions. We performed fusion imaging with virtual navigation for patients undergoing surgery for brain lesion removal using an ultrasound-based real-time neuro-navigation system that fuses intraoperative cerebral ultrasound with preoperative MRI and simultaneously displays an MRI slice coplanar to an ioUS image. 58 patients underwent surgery at our institution for intracranial lesion removal with image guidance using a US system equipped with fusion imaging for neuro-navigation. In all cases the initial (external) registration error obtained by the corresponding anatomical landmark procedure was below 2 mm and the craniotomy was correctly placed. The transdural window gave satisfactory US image quality and the lesion was always detectable and measurable on both axes. Brain shift/deformation correction has been successfully employed in 42 cases to restore the co-registration during surgery. The accuracy of ioUS/MRI fusion/overlapping was confirmed intraoperatively under direct visualization of anatomic landmarks and the error was surgery and is less expensive and time-consuming than other intraoperative imaging techniques, offering high precision and
Added Value of Contrast-Enhanced Ultrasound on Biopsies of Focal Hepatic Lesions Invisible on Fusion Imaging Guidance.

Science.gov (United States)

Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

2017-01-01

To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5-1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.
Usefulness of ultrasound-guided mammotome biopsy for microcalcification

Energy Technology Data Exchange (ETDEWEB)

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

2005-08-15

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

International Nuclear Information System (INIS)

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

2005-01-01

To evaluate the usefulness of ultrasound-guided mammotome biopsy for microcalcification and to suggest a new approach for the localization of microcalcifications which are not detected on ultrasound. Twenty-one calcific lesions in 21 women (aged 33-56 years) underwent ultrasound-guided, vacuum-assisted, mammotome biopsy and a mean of 14 specimens per lesion were obtained. Calcification retrieval was defined as identification of calcifications on specimen radiographs. In the 13 cases of calcifications which were not detected on ultrasound imaging, mammotome biopsy was performed after localization of one or two needles at the microcalcifications under mammography-guidance. Radiographs of the specimens and histologic findings were reviewed and scheduled follow-up imaging was performed for evaluation of the complications of biopsy. Ultrasound-guided, vacuum-assisted, mammotome biopsy removed all calcifications in 21 lesions. Eight (38%) lesions showed visible calcification on the ultrasound while 13 (62%) lesions were invisible, which underwent mammotome biopsy after needle localization under mammography-guidance. Surgery revealed DCIS in 1 (4.8%) of 21 lesions, infiltrating ductal carcinoma in two (9.5%), fibroadenomas with calcifications in 6 (28.6%), fibroadenmas with adenosis in 2(9.5%), and fibrocystic change with calcifications in 10 (47.6%). Clinical significant complications did not occur on follow-up examination in any of the cases. Ultrasound-guided, vacuum-assisted, mammotome biopsy was an effective method for microcalcifications on mammogram. The results suggested that mammotome biopsy after mammogram-guided, needle localization is a good alternative method for the diagnosis of microcalcifications which are undetectable in the ultrasound images
WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance

Energy Technology Data Exchange (ETDEWEB)

Zagzebski, J. [University of Wisconsin (United States)

2016-06-15

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.

WE-AB-206-01: Diagnostic Ultrasound Imaging Quality Assurance

International Nuclear Information System (INIS)

Zagzebski, J.

2016-01-01

The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. The goal of this ultrasound hands-on workshop is to demonstrate quality control (QC) testing in diagnostic ultrasound and to provide updates in ACR ultrasound accreditation requirements. The first half of this workshop will include two presentations reviewing diagnostic ultrasound QA/QC and ACR ultrasound accreditation requirements. The second half of the workshop will include live demonstrations of basic QC tests. An array of ultrasound testing phantoms and ultrasound scanners will be available for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations and on-site instructors. The targeted attendees are medical physicists in diagnostic imaging. Learning Objectives: Gain familiarity with common elements of a QA/QC program for diagnostic ultrasound imaging dentify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools Learn ACR ultrasound accreditation requirements Jennifer Walter is an employee of American College of Radiology on Ultrasound Accreditation.
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound procedure View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Angioplasty and Vascular Stenting ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... biopsies , in which needles are used to sample cells from an abnormal area for laboratory testing. image the breasts and guide biopsy of breast cancer ( see the Ultrasound-Guided Breast Biopsy page . diagnose ...
Varying ultrasound power level to distinguish surgical instruments and tissue.

Science.gov (United States)

Ren, Hongliang; Anuraj, Banani; Dupont, Pierre E

2018-03-01

We investigate a new framework of surgical instrument detection based on power-varying ultrasound images with simple and efficient pixel-wise intensity processing. Without using complicated feature extraction methods, we identified the instrument with an estimated optimal power level and by comparing pixel values of varying transducer power level images. The proposed framework exploits the physics of ultrasound imaging system by varying the transducer power level to effectively distinguish metallic surgical instruments from tissue. This power-varying image-guidance is motivated from our observations that ultrasound imaging at different power levels exhibit different contrast enhancement capabilities between tissue and instruments in ultrasound-guided robotic beating-heart surgery. Using lower transducer power levels (ranging from 40 to 75% of the rated lowest ultrasound power levels of the two tested ultrasound scanners) can effectively suppress the strong imaging artifacts from metallic instruments and thus, can be utilized together with the images from normal transducer power levels to enhance the separability between instrument and tissue, improving intraoperative instrument tracking accuracy from the acquired noisy ultrasound volumetric images. We performed experiments in phantoms and ex vivo hearts in water tank environments. The proposed multi-level power-varying ultrasound imaging approach can identify robotic instruments of high acoustic impedance from low-signal-to-noise-ratio ultrasound images by power adjustments.
Management of mediastinal syndromes in pediatrics: a new challenge of ultrasound guidance to avoid high-risk general anesthesia.

Science.gov (United States)

Sola, Chrystelle; Choquet, Olivier; Prodhomme, Olivier; Capdevila, Xavier; Dadure, Christophe

2014-05-01

Adverse events associated with anesthetic management of anterior mediastinal masses in pediatrics are common. To avoid an extremely hazardous general anesthesia, the use of real-time ultrasonography offers an effective alternative in high-risk cases. We report the anesthetic management including a light sedation and ultrasound guidance for regional anesthesia, surgical node biopsy, and placement of a central venous line in two children with an anterior symptomatic mediastinal mass. For pediatric patients with clinical and/or radiologic signs of airway compression, ultrasound guidance provides safety technical assistance to avoid general anesthesia and should be performed for the initial diagnostic and therapeutic procedures. © 2013 John Wiley & Sons Ltd.
Real-time ultrasound image classification for spine anesthesia using local directional Hadamard features.

Science.gov (United States)

Pesteie, Mehran; Abolmaesumi, Purang; Ashab, Hussam Al-Deen; Lessoway, Victoria A; Massey, Simon; Gunka, Vit; Rohling, Robert N

2015-06-01

Injection therapy is a commonly used solution for back pain management. This procedure typically involves percutaneous insertion of a needle between or around the vertebrae, to deliver anesthetics near nerve bundles. Most frequently, spinal injections are performed either blindly using palpation or under the guidance of fluoroscopy or computed tomography. Recently, due to the drawbacks of the ionizing radiation of such imaging modalities, there has been a growing interest in using ultrasound imaging as an alternative. However, the complex spinal anatomy with different wave-like structures, affected by speckle noise, makes the accurate identification of the appropriate injection plane difficult. The aim of this study was to propose an automated system that can identify the optimal plane for epidural steroid injections and facet joint injections. A multi-scale and multi-directional feature extraction system to provide automated identification of the appropriate plane is proposed. Local Hadamard coefficients are obtained using the sequency-ordered Hadamard transform at multiple scales. Directional features are extracted from local coefficients which correspond to different regions in the ultrasound images. An artificial neural network is trained based on the local directional Hadamard features for classification. The proposed method yields distinctive features for classification which successfully classified 1032 images out of 1090 for epidural steroid injection and 990 images out of 1052 for facet joint injection. In order to validate the proposed method, a leave-one-out cross-validation was performed. The average classification accuracy for leave-one-out validation was 94 % for epidural and 90 % for facet joint targets. Also, the feature extraction time for the proposed method was 20 ms for a native 2D ultrasound image. A real-time machine learning system based on the local directional Hadamard features extracted by the sequency-ordered Hadamard transform for
General Ultrasound Imaging

Medline Plus

Full Text Available ... biopsies , in which needles are used to sample cells from an abnormal area for laboratory testing. image ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... image the breasts and guide biopsy of breast cancer ( see the Ultrasound-Guided Breast Biopsy page . diagnose ... are sometimes the best way to see if treatment is working or if a finding is stable ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... a follow-up exam is done because a potential abnormality needs further evaluation with additional views or ... of soft tissues that do not show up well on x-ray images. Ultrasound is the preferred ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... heartbeat. top of page What are some common uses of the procedure? Ultrasound examinations can help to ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... needles are used to sample cells from an abnormal area for laboratory testing. image the breasts and ... of organs, tissues, and vessels or to detect abnormal masses, such as tumors. In an ultrasound examination, ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... the transducer for analysis. Ultrasound has difficulty penetrating bone and, therefore, can only see the outer surface ... children or adults). For visualizing internal structure of bones or certain joints, other imaging modalities such as ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow- ... Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... ultrasound images are captured in real-time, they can show the structure and movement of the body's ... time, rather than as a color picture. It can also convert blood flow information into a distinctive ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... patient. Because ultrasound images are captured in real-time, they can show the structure and movement of ... terms of the distance traveled per unit of time, rather than as a color picture. It can ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... echoes from the tissues in the body. The principles are similar to sonar used by boats and ... work? Ultrasound imaging is based on the same principles involved in the sonar used by bats, ships ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... consist of a console containing a computer and electronics, a video display screen and a transducer that ... the preferred imaging modality for the diagnosis and monitoring of pregnant women and their unborn babies. Ultrasound ...
Musculoskeletal ultrasound and other imaging modalities in rheumatoid arthritis.

Science.gov (United States)

Ohrndorf, Sarah; Werner, Stephanie G; Finzel, Stephanie; Backhaus, Marina

2013-05-01

This review refers to the use of musculoskeletal ultrasound in patients with rheumatoid arthritis (RA) both in clinical practice and research. Furthermore, other novel sensitive imaging modalities (high resolution peripheral quantitative computed tomography and fluorescence optical imaging) are introduced in this article. Recently published ultrasound studies presented power Doppler activity by ultrasound highly predictive for later radiographic erosions in patients with RA. Another study presented synovitis detected by ultrasound being predictive of subsequent structural radiographic destruction irrespective of the ultrasound modality (grayscale ultrasound/power Doppler ultrasound). Further studies are currently under way which prove ultrasound findings as imaging biomarkers in the destructive process of RA. Other introduced novel imaging modalities are in the validation process to prove their impact and significance in inflammatory joint diseases. The introduced imaging modalities show different sensitivities and specificities as well as strength and weakness belonging to the assessment of inflammation, differentiation of the involved structures and radiological progression. The review tries to give an answer regarding how to best integrate them into daily clinical practice with the aim to improve the diagnostic algorithms, the daily patient care and, furthermore, the disease's outcome.
General Ultrasound Imaging

Medline Plus

Full Text Available ... is General Ultrasound Imaging? What are some common uses of the procedure? How should I prepare? What does the equipment look like? How does the procedure work? How is the procedure performed? What will I ...
Pulsed radiofrequency of brachial plexus under ultrasound guidance for refractory stump pain: a case report

Directory of Open Access Journals (Sweden)

Zheng B

2017-11-01

Full Text Available Bixin Zheng, Li Song, Hui Liu Department of Pain Management, West China Hospital of Sichuan University, Chengdu, China Abstract: The post-amputation (pain syndrome, including stump pain, phantom limb sensation, and phantom limb pain is common but difficult to treat. Refractory stump pain in the syndrome is an extremely challenging and troublesome clinical condition. Patients respond poorly to drugs, nerve blocks, and other effective treatments like spinal cord stimulation and surgery. Pulsed radiofrequency (PRF technique has been shown to be effective in reducing neuropathic pain. This report describes a patient with persistent and refractory upper limb stump pain being successfully relieved with PRF of brachial plexus under ultrasound guidance after a 6-month follow-up period, suggesting that PRF may be considered as an alternative treatment for refractory stump-neuroma pain. Keywords: ultrasound guidance, pulsed radiofrequency, brachial plexus, refractory stump pain

Stereoscopic Integrated Imaging Goggles for Multimodal Intraoperative Image Guidance.

Directory of Open Access Journals (Sweden)

Christopher A Mela

Full Text Available We have developed novel stereoscopic wearable multimodal intraoperative imaging and display systems entitled Integrated Imaging Goggles for guiding surgeries. The prototype systems offer real time stereoscopic fluorescence imaging and color reflectance imaging capacity, along with in vivo handheld microscopy and ultrasound imaging. With the Integrated Imaging Goggle, both wide-field fluorescence imaging and in vivo microscopy are provided. The real time ultrasound images can also be presented in the goggle display. Furthermore, real time goggle-to-goggle stereoscopic video sharing is demonstrated, which can greatly facilitate telemedicine. In this paper, the prototype systems are described, characterized and tested in surgeries in biological tissues ex vivo. We have found that the system can detect fluorescent targets with as low as 60 nM indocyanine green and can resolve structures down to 0.25 mm with large FOV stereoscopic imaging. The system has successfully guided simulated cancer surgeries in chicken. The Integrated Imaging Goggle is novel in 4 aspects: it is (a the first wearable stereoscopic wide-field intraoperative fluorescence imaging and display system, (b the first wearable system offering both large FOV and microscopic imaging simultaneously,
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.
Contrast-enhanced harmonic endoscopic ultrasound

DEFF Research Database (Denmark)

Săftoiu, A; Dietrich, C F; Vilmann, P

2012-01-01

Second-generation intravenous blood-pool ultrasound contrast agents are increasingly used in endoscopic ultrasound (EUS) for characterization of microvascularization, differential diagnosis of benign and malignant focal lesions, and improving staging and guidance of therapeutic procedures. Although...... initially used as Doppler signal enhancers, second-generation microbubble contrast agents are now used with specific contrast harmonic imaging techniques, which benefit from the highly nonlinear behavior of the microbubbles. Contrast-specific modes based on multi-pulse technology are used to perform...... contrast-enhanced harmonic EUS based on a very low mechanical index (0.08 - 0.12). Quantification techniques based on dynamic contrast-enhanced ultrasound have been recommended for perfusion imaging and monitoring of anti-angiogenic treatment, mainly based on time-intensity curve analysis. Most...
General Ultrasound Imaging

Medline Plus

Full Text Available ... the patient. Because ultrasound images are captured in real-time, they can show the structure and movement of ... by a computer, which in turn creates a real-time picture on the monitor. One or more frames ...
Added value of contrast-enhanced ultrasound on biopsies of focal hepatic lesions invisible on fusion imaging guidance

Energy Technology Data Exchange (ETDEWEB)

Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2017-01-15

To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making.
Added value of contrast-enhanced ultrasound on biopsies of focal hepatic lesions invisible on fusion imaging guidance

International Nuclear Information System (INIS)

Kang, Tae Wook; Lee, Min Woo; Song, Kyoung Doo; Kim, Mimi; Kim, Seung Soo; Kim, Seong Hyun; Ha, Sang Yun

2017-01-01

To assess whether contrast-enhanced ultrasonography (CEUS) with Sonazoid can improve the lesion conspicuity and feasibility of percutaneous biopsies for focal hepatic lesions invisible on fusion imaging of real-time ultrasonography (US) with computed tomography/magnetic resonance images, and evaluate its impact on clinical decision making. The Institutional Review Board approved this retrospective study. Between June 2013 and January 2015, 711 US-guided percutaneous biopsies were performed for focal hepatic lesions. Biopsies were performed using CEUS for guidance if lesions were invisible on fusion imaging. We retrospectively evaluated the number of target lesions initially invisible on fusion imaging that became visible after applying CEUS, using a 4-point scale. Technical success rates of biopsies were evaluated based on histopathological results. In addition, the occurrence of changes in clinical decision making was assessed. Among 711 patients, 16 patients (2.3%) were included in the study. The median size of target lesions was 1.1 cm (range, 0.5–1.9 cm) in pre-procedural imaging. After CEUS, 15 of 16 (93.8%) focal hepatic lesions were visualized. The conspicuity score was significantly increased after adding CEUS, as compared to that on fusion imaging (p < 0.001). The technical success rate of biopsy was 87.6% (14/16). After biopsy, there were changes in clinical decision making for 11 of 16 patients (68.8%). The addition of CEUS could improve the conspicuity of focal hepatic lesions invisible on fusion imaging. This dual guidance using CEUS and fusion imaging may affect patient management via changes in clinical decision-making
Motion Detection in Ultrasound Image-Sequences Using Tensor Voting

Science.gov (United States)

Inba, Masafumi; Yanagida, Hirotaka; Tamura, Yasutaka

2008-05-01

Motion detection in ultrasound image sequences using tensor voting is described. We have been developing an ultrasound imaging system adopting a combination of coded excitation and synthetic aperture focusing techniques. In our method, frame rate of the system at distance of 150 mm reaches 5000 frame/s. Sparse array and short duration coded ultrasound signals are used for high-speed data acquisition. However, many artifacts appear in the reconstructed image sequences because of the incompleteness of the transmitted code. To reduce the artifacts, we have examined the application of tensor voting to the imaging method which adopts both coded excitation and synthetic aperture techniques. In this study, the basis of applying tensor voting and the motion detection method to ultrasound images is derived. It was confirmed that velocity detection and feature enhancement are possible using tensor voting in the time and space of simulated ultrasound three-dimensional image sequences.
Advanced 3-D Ultrasound Imaging

DEFF Research Database (Denmark)

Rasmussen, Morten Fischer

The main purpose of the PhD project was to develop methods that increase the 3-D ultrasound imaging quality available for the medical personnel in the clinic. Acquiring a 3-D volume gives the medical doctor the freedom to investigate the measured anatomy in any slice desirable after the scan has...... been completed. This allows for precise measurements of organs dimensions and makes the scan more operator independent. Real-time 3-D ultrasound imaging is still not as widespread in use in the clinics as 2-D imaging. A limiting factor has traditionally been the low image quality achievable using...... a channel limited 2-D transducer array and the conventional 3-D beamforming technique, Parallel Beamforming. The first part of the scientific contributions demonstrate that 3-D synthetic aperture imaging achieves a better image quality than the Parallel Beamforming technique. Data were obtained using both...
Enhancement of bone shadow region using local phase-based ultrasound transmission maps.

Science.gov (United States)

Hacihaliloglu, Ilker

2017-06-01

Ultrasound is increasingly being employed in different orthopedic procedures as an imaging modality for real-time guidance. Nevertheless, low signal-to-noise-ratio and different imaging artifacts continue to hamper the success of ultrasound-based procedures. Bone shadow region is an important feature indicating the presence of bone/tissue interface in the acquired ultrasound data. Enhancement and automatic detection of this region could improve the sensitivity of ultrasound for imaging bone and result in improved guidance for various orthopedic procedures. In this work, a method is introduced for the enhancement of bone shadow regions from B-mode ultrasound data. The method is based on the combination of three different image phase features: local phase tensor, local weighted mean phase angle, and local phase energy. The combined local phase image features are used as an input to an [Formula: see text] norm-based contextual regularization method which emphasizes uncertainty in the shadow regions. The enhanced bone shadow images are automatically segmented and compared against expert segmentation. Qualitative and quantitative validation was performed on 100 in vivo US scans obtained from five subjects by scanning femur and vertebrae bones. Validation against expert segmentation achieved a mean dice similarity coefficient of 0.88. The encouraging results obtained in this initial study suggest that the proposed method is promising enough for further evaluation. The calculated bone shadow maps could be incorporated into different ultrasound bone segmentation and registration approaches as an additional feature.
Ultrasound Imaging and its modeling

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt

2002-01-01

Modern medical ultrasound scanners are used for imaging nearly all soft tissue structures in the body. The anatomy can be studied from gray-scale B-mode images, where the reflectivity and scattering strength of the tissues are displayed. The imaging is performed in real time with 20 to 100 images...
Online 4D ultrasound guidance for real-time motion compensation by MLC tracking.

Science.gov (United States)

Ipsen, Svenja; Bruder, Ralf; O'Brien, Rick; Keall, Paul J; Schweikard, Achim; Poulsen, Per R

2016-10-01

With the trend in radiotherapy moving toward dose escalation and hypofractionation, the need for highly accurate targeting increases. While MLC tracking is already being successfully used for motion compensation of moving targets in the prostate, current real-time target localization methods rely on repeated x-ray imaging and implanted fiducial markers or electromagnetic transponders rather than direct target visualization. In contrast, ultrasound imaging can yield volumetric data in real-time (3D + time = 4D) without ionizing radiation. The authors report the first results of combining these promising techniques-online 4D ultrasound guidance and MLC tracking-in a phantom. A software framework for real-time target localization was installed directly on a 4D ultrasound station and used to detect a 2 mm spherical lead marker inside a water tank. The lead marker was rigidly attached to a motion stage programmed to reproduce nine characteristic tumor trajectories chosen from large databases (five prostate, four lung). The 3D marker position detected by ultrasound was transferred to a computer program for MLC tracking at a rate of 21.3 Hz and used for real-time MLC aperture adaption on a conventional linear accelerator. The tracking system latency was measured using sinusoidal trajectories and compensated for by applying a kernel density prediction algorithm for the lung traces. To measure geometric accuracy, static anterior and lateral conformal fields as well as a 358° arc with a 10 cm circular aperture were delivered for each trajectory. The two-dimensional (2D) geometric tracking error was measured as the difference between marker position and MLC aperture center in continuously acquired portal images. For dosimetric evaluation, VMAT treatment plans with high and low modulation were delivered to a biplanar diode array dosimeter using the same trajectories. Dose measurements with and without MLC tracking were compared to a static reference dose using 3%/3 mm and 2
TU-EF-210-00: Therapeutic Strategies and Image Guidance

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-06-15

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare.
TU-EF-210-00: Therapeutic Strategies and Image Guidance

International Nuclear Information System (INIS)

2015-01-01

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare
Ultrasound Imaging Initiative

Science.gov (United States)

2003-01-01

texture mapping hardware," IEEE Tranactions on Information Technology in Biomedicine, Submitted. [14] C.R. Castro Pareja , J.M. Jagadeesh and R. Shekhar...modulation in real-time three-dimensional sparse synthetic aperture ultrasound imaging systems "* Carlos R. Castro Pareja , Masters of Science, The Ohio...C.R. Castro Pareja , "An architecture for real-time image registration," M.S. Thesis, The Ohio State University, March 2002. 14. C.R. Castro Pareja , R
Advantages of computed tomographic guidance

International Nuclear Information System (INIS)

Casola, G.; Vansonnenberg, E.

1987-01-01

Both ultrasound and CT are successfully used to guide interventional procedures throughout the body. There are advantages and disadvantages to each modality and choosing one over the other will vary from case to case. Major factors influencing choice are discussed in this paper. As a general rule CT guidance is usually required for lesions in the thorax, the adrenals, the pancreas, lymph nodes, and for percutaneous abscess drainage. The authors feel that a complimentary use of ultrasound and CT is essential to optimize success and cost-effectiveness; therefore, the interventional radiologist should be familiar with both imaging modalities
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... abdomen, arms, legs, neck and/or brain (in infants and children) or within various body organs such ... abdomen help determine causes of vomiting in young infants Because ultrasound provides real-time images, images that ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... to-use and less expensive than other imaging methods. Ultrasound imaging is extremely safe and does not ... barium exams, CT scanning , and MRI are the methods of choice in such a setting. Large patients ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... kidneys. top of page What are some common uses of the procedure? Abdominal ultrasound imaging is performed ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - ... computer or television monitor. The image is created based on the amplitude (loudness), frequency (pitch) and time ...
MLESAC Based Localization of Needle Insertion Using 2D Ultrasound Images

Science.gov (United States)

Xu, Fei; Gao, Dedong; Wang, Shan; Zhanwen, A.

2018-04-01

In the 2D ultrasound image of ultrasound-guided percutaneous needle insertions, it is difficult to determine the positions of needle axis and tip because of the existence of artifacts and other noises. In this work the speckle is regarded as the noise of an ultrasound image, and a novel algorithm is presented to detect the needle in a 2D ultrasound image. Firstly, the wavelet soft thresholding technique based on BayesShrink rule is used to denoise the speckle of ultrasound image. Secondly, we add Otsu’s thresholding method and morphologic operations to pre-process the ultrasound image. Finally, the localization of the needle is identified and positioned in the 2D ultrasound image based on the maximum likelihood estimation sample consensus (MLESAC) algorithm. The experimental results show that it is valid for estimating the position of needle axis and tip in the ultrasound images with the proposed algorithm. The research work is hopeful to be used in the path planning and robot-assisted needle insertion procedures.

pH/Ultrasound Dual-Responsive Gas Generator for Ultrasound Imaging-Guided Therapeutic Inertial Cavitation and Sonodynamic Therapy.

Science.gov (United States)

Feng, Qianhua; Zhang, Wanxia; Yang, Xuemei; Li, Yuzhen; Hao, Yongwei; Zhang, Hongling; Hou, Lin; Zhang, Zhenzhong

2018-03-01

Herein, a pH/ultrasound dual-responsive gas generator is reported, which is based on mesoporous calcium carbonate (MCC) nanoparticles by loading sonosensitizer (hematoporphyrin monomethyl ether (HMME)) and modifying surface hyaluronic acid (HA). After pinpointing tumor regions with prominent targeting efficiency, HMME/MCC-HA decomposes instantaneously under the cotriggering of tumoral inherent acidic condition and ultrasound (US) irradiation, concurrently accompanying with CO 2 generation and HMME release with spatial/temporal resolution. Afterward, the CO 2 bubbling and bursting effect under US stimulus results in cavitation-mediated irreversible cell necrosis, as well as the blood vessel destruction to further occlude the blood supply, providing a "bystander effect." Meanwhile, reactive oxygen species generated from HMME can target the apoptotic pathways for effective sonodynamic therapy. Thus, the combination of apoptosis/necrosis with multimechanisms consequently results in a remarkable antitumor therapeutic efficacy, simultaneously minimizing the side effects on major organs. Moreover, the echogenic property of CO 2 make the nanoplatform as a powerful ultrasound contrast agent to identify cancerous lesions. Based on the above findings, such all-in-one drug delivery platform of HMME/MCC-HA is utilized to provide the US imaging guidance for therapeutic inertial cavitation and sonodynamic therapy simultaneously, which highlights possibilities of advancing cancer theranostics in biomedical fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Comparative study of ultrasound imaging, computed tomography and magnetic resonance imaging in gynecology

International Nuclear Information System (INIS)

Ishii, Kenji; Kobayashi, Hisaaki; Hoshihara, Takayuki; Kobayashi, Mitsunao; Suda, Yoshio; Takenaka, Eiichi; Sasa, Hidenori.

1989-01-01

We studied 18 patients who were operated at the National Defense Medical College Hospital and confirmed by pathological diagnosis. We compared ultrasound imaging, computed tomography (CT) and magnetic resonance imaging (MRI) of the patients. MRI was useful to diagnose enlargement of the uterine cavity and a small amount of ascites and to understand orientation of the pelvic organs. Ultrasound imaging is the most useful examination to diagnose gynecological diseases. But when it is difficult to diagnose by ultrasound imaging alone, we should employ either CT or MRI, or preferably both. (author)
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... do not use ionizing radiation (as used in x-rays ), thus there is no radiation exposure to the ... tissues that do not show up well on x-ray images. Ultrasound provides real-time imaging, making it ...
Simulation Study of Effects of the Blind Deconvolution on Ultrasound Image

Science.gov (United States)

He, Xingwu; You, Junchen

2018-03-01

Ultrasonic image restoration is an essential subject in Medical Ultrasound Imaging. However, without enough and precise system knowledge, some traditional image restoration methods based on the system prior knowledge often fail to improve the image quality. In this paper, we use the simulated ultrasound image to find the effectiveness of the blind deconvolution method for ultrasound image restoration. Experimental results demonstrate that the blind deconvolution method can be applied to the ultrasound image restoration and achieve the satisfactory restoration results without the precise prior knowledge, compared with the traditional image restoration method. And with the inaccurate small initial PSF, the results shows blind deconvolution could improve the overall image quality of ultrasound images, like much better SNR and image resolution, and also show the time consumption of these methods. it has no significant increasing on GPU platform.
Spatial Angular Compounding Technique for H-Scan Ultrasound Imaging.

Science.gov (United States)

Khairalseed, Mawia; Xiong, Fangyuan; Kim, Jung-Whan; Mattrey, Robert F; Parker, Kevin J; Hoyt, Kenneth

2018-01-01

H-Scan is a new ultrasound imaging technique that relies on matching a model of pulse-echo formation to the mathematics of a class of Gaussian-weighted Hermite polynomials. This technique may be beneficial in the measurement of relative scatterer sizes and in cancer therapy, particularly for early response to drug treatment. Because current H-scan techniques use focused ultrasound data acquisitions, spatial resolution degrades away from the focal region and inherently affects relative scatterer size estimation. Although the resolution of ultrasound plane wave imaging can be inferior to that of traditional focused ultrasound approaches, the former exhibits a homogeneous spatial resolution throughout the image plane. The purpose of this study was to implement H-scan using plane wave imaging and investigate the impact of spatial angular compounding on H-scan image quality. Parallel convolution filters using two different Gaussian-weighted Hermite polynomials that describe ultrasound scattering events are applied to the radiofrequency data. The H-scan processing is done on each radiofrequency image plane before averaging to get the angular compounded image. The relative strength from each convolution is color-coded to represent relative scatterer size. Given results from a series of phantom materials, H-scan imaging with spatial angular compounding more accurately reflects the true scatterer size caused by reductions in the system point spread function and improved signal-to-noise ratio. Preliminary in vivo H-scan imaging of tumor-bearing animals suggests this modality may be useful for monitoring early response to chemotherapeutic treatment. Overall, H-scan imaging using ultrasound plane waves and spatial angular compounding is a promising approach for visualizing the relative size and distribution of acoustic scattering sources. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.
Mesoporous composite nanoparticles for dual-modality ultrasound/magnetic resonance imaging and synergistic chemo-/thermotherapy against deep tumors

Directory of Open Access Journals (Sweden)

Zhang N

2017-10-01

Full Text Available Nan Zhang,1 Ronghui Wang,2 Junnian Hao,1 Yang Yang,1 Hongmi Zou,3 Zhigang Wang1 1Chongqing Key Laboratory of Ultrasound Molecular Imaging, Second Affiliated Hospital of Chongqing Medical University, Chongqing Medical University, Chongqing, 2Department of Ultrasound, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 3Department of Ophthalmology, Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Abstract: High-intensity focused ultrasound (HIFU is a promising and noninvasive treatment for solid tumors, which has been explored for potential clinical applications. However, the clinical applications of HIFU for large and deep tumors such as hepatocellular carcinoma (HCC are severely limited by unsatisfactory imaging guidance, long therapeutic times, and damage to normal tissue around the tumor due to the high power applied. In this study, we developed doxorubicin/perfluorohexane-encapsulated hollow mesoporous Prussian blue nanoparticles (HMPBs-DOX/PFH as theranostic agents, which can effectively guide HIFU therapy and enhance its therapeutic effects in combination with chemotherapy, by decreasing the cavitation threshold. We investigated the effects of this agent on ultrasound and magnetic resonance imaging in vitro and in vivo. In addition, we showed a highly efficient HIFU therapeutic effect against HCC tumors, as well as controlled drug release, owing to the phase-transitional performance of the PFH. We therefore conclude that HMPB-DOX/PFH is a safe and efficient nanoplatform, which holds significant promise for cancer theranostics against deep tumors in clinical settings. Keywords: high-intensity focused ultrasound, HIFU, hollow mesoporous Prussian blue nanoplatforms, hepatocellular carcinoma, dual-modality imaging, synergistic chemo-/thermotherapy, theranostics
Plane Wave Medical Ultrasound Imaging Using Adaptive Beamforming

DEFF Research Database (Denmark)

Holfort, Iben Kraglund; Gran, Fredrik; Jensen, Jørgen Arendt

2008-01-01

In this paper, the adaptive, minimum variance (MV) beamformer is applied to medical ultrasound imaging. The Significant resolution and contrast gain provided by the adaptive, minimum variance (MV) beamformer, introduces the possibility of plane wave (PW) ultrasound imaging. Data is obtained using...
Ultrasound contrast-agent improves imaging of lower limb occlusive disease

DEFF Research Database (Denmark)

Eiberg, J P; Hansen, M A; Jensen, F

2003-01-01

to evaluate if ultrasound contrast-agent infusion could improve duplex-ultrasound imaging of peripheral arterial disease (PAD) and increase the agreement with digital subtraction arteriography (DSA).......to evaluate if ultrasound contrast-agent infusion could improve duplex-ultrasound imaging of peripheral arterial disease (PAD) and increase the agreement with digital subtraction arteriography (DSA)....
Ultrasound strain imaging using Barker code

Science.gov (United States)

Peng, Hui; Tie, Juhong; Guo, Dequan

2017-01-01

Ultrasound strain imaging is showing promise as a new way of imaging soft tissue elasticity in order to help clinicians detect lesions or cancers in tissues. In this paper, Barker code is applied to strain imaging to improve its quality. Barker code as a coded excitation signal can be used to improve the echo signal-to-noise ratio (eSNR) in ultrasound imaging system. For the Baker code of length 13, the sidelobe level of the matched filter output is -22dB, which is unacceptable for ultrasound strain imaging, because high sidelobe level will cause high decorrelation noise. Instead of using the conventional matched filter, we use the Wiener filter to decode the Barker-coded echo signal to suppress the range sidelobes. We also compare the performance of Barker code and the conventional short pulse in simulation method. The simulation results demonstrate that the performance of the Wiener filter is much better than the matched filter, and Baker code achieves higher elastographic signal-to-noise ratio (SNRe) than the short pulse in low eSNR or great depth conditions due to the increased eSNR with it.
Evaluation of multimodality imaging using image fusion with ultrasound tissue elasticity imaging in an experimental animal model.

Science.gov (United States)

Paprottka, P M; Zengel, P; Cyran, C C; Ingrisch, M; Nikolaou, K; Reiser, M F; Clevert, D A

2014-01-01

To evaluate the ultrasound tissue elasticity imaging by comparison to multimodality imaging using image fusion with Magnetic Resonance Imaging (MRI) and conventional grey scale imaging with additional elasticity-ultrasound in an experimental small-animal-squamous-cell carcinoma-model for the assessment of tissue morphology. Human hypopharynx carcinoma cells were subcutaneously injected into the left flank of 12 female athymic nude rats. After 10 days (SD ± 2) of subcutaneous tumor growth, sonographic grey scale including elasticity imaging and MRI measurements were performed using a high-end ultrasound system and a 3T MR. For image fusion the contrast-enhanced MRI DICOM data set was uploaded in the ultrasonic device which has a magnetic field generator, a linear array transducer (6-15 MHz) and a dedicated software package (GE Logic E9), that can detect transducers by means of a positioning system. Conventional grey scale and elasticity imaging were integrated in the image fusion examination. After successful registration and image fusion the registered MR-images were simultaneously shown with the respective ultrasound sectional plane. Data evaluation was performed using the digitally stored video sequence data sets by two experienced radiologist using a modified Tsukuba Elasticity score. The colors "red and green" are assigned for an area of soft tissue, "blue" indicates hard tissue. In all cases a successful image fusion and plan registration with MRI and ultrasound imaging including grey scale and elasticity imaging was possible. The mean tumor volume based on caliper measurements in 3 dimensions was ~323 mm3. 4/12 rats were evaluated with Score I, 5/12 rates were evaluated with Score II, 3/12 rates were evaluated with Score III. There was a close correlation in the fused MRI with existing small necrosis in the tumor. None of the scored II or III lesions was visible by conventional grey scale. The comparison of ultrasound tissue elasticity imaging enables a
Electromagnetic-Tracked Biopsy under Ultrasound Guidance: Preliminary Results

International Nuclear Information System (INIS)

Hakime, Antoine; Deschamps, Frederic; Marques De Carvalho, Enio Garcia; Barah, Ali; Auperin, Anne; Baere, Thierry De

2012-01-01

Purpose: This study was designed to evaluate the accuracy and safety of electromagnetic needle tracking for sonographically guided percutaneous liver biopsies. Methods: We performed 23 consecutive ultrasound-guided liver biopsies for liver nodules with an electromagnetic tracking of the needle. A sensor placed at the tip of a sterile stylet (18G) inserted in a coaxial guiding trocar (16G) used for biopsy was localized in real time relative to the ultrasound imaging plane, thanks to an electromagnetic transmitter and two sensors on the ultrasound probe. This allows for electronic display of the needle tip location and the future needle path overlaid on the real-time ultrasound image. Distance between needle tip position and its electronic display, number of needle punctures, number of needle pull backs for redirection, technical success (needle positioned in the target), diagnostic success (correct histopathology result), procedure time, and complication were evaluated according to lesion sizes, depth and location, operator experience, and “in-plane” or “out-of-plane” needle approach. Results: Electronic display was always within 2 mm from the real position of the needle tip. The technical success rate was 100%. A single needle puncture without repuncture was used in all patients. Pull backs were necessary in six patients (26%) to obtain correct needle placement. The overall diagnostic success rate was 91%. The overall true-positive, true-negative, false-negative, and failure rates of the biopsy were 100% (19/19) 100% (2/2), 0% (0/23), and 9% (2/23). The median total procedure time from the skin puncture to the needle in the target was 30 sec (from 5–60 s). Lesion depth and localizations, operator experience, in-plane or out-of-plane approach did not affect significantly the technical, diagnostic success, or procedure time. Even when the tumor size decreased, the procedure time did not increase. Conclusions: Electromagnetic-tracked biopsy is accurate to
3D ultrasound imaging : Fast and cost-effective morphometry of musculoskeletal tissue

NARCIS (Netherlands)

Weide, Guido; Van Der Zwaard, Stephan; Huijing, Peter A.; Jaspers, Richard T.; Harlaar, Jaap

2017-01-01

The developmental goal of 3D ultrasound imaging (3DUS) is to engineer a modality to perform 3D morphological ultrasound analysis of human muscles. 3DUS images are constructed from calibrated freehand 2D B-mode ultrasound images, which are positioned into a voxel array. Ultrasound (US) imaging allows
Synthetic Aperture Ultrasound Imaging

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt; Nikolov, Svetoslav; Gammelmark, Kim Løkke

2006-01-01

The paper describes the use of synthetic aperture (SA) imaging in medical ultrasound. SA imaging is a radical break with today's commercial systems, where the image is acquired sequentially one image line at a time. This puts a strict limit on the frame rate and the possibility of acquiring...... a sufficient amount of data for high precision flow estimation. These constrictions can be lifted by employing SA imaging. Here data is acquired simultaneously from all directions over a number of emissions, and the full image can be reconstructed from this data. The talk will demonstrate the many benefits...
Robot-assisted ultrasound imaging: overview and development of a parallel telerobotic system.

Science.gov (United States)

Monfaredi, Reza; Wilson, Emmanuel; Azizi Koutenaei, Bamshad; Labrecque, Brendan; Leroy, Kristen; Goldie, James; Louis, Eric; Swerdlow, Daniel; Cleary, Kevin

2015-02-01

Ultrasound imaging is frequently used in medicine. The quality of ultrasound images is often dependent on the skill of the sonographer. Several researchers have proposed robotic systems to aid in ultrasound image acquisition. In this paper we first provide a short overview of robot-assisted ultrasound imaging (US). We categorize robot-assisted US imaging systems into three approaches: autonomous US imaging, teleoperated US imaging, and human-robot cooperation. For each approach several systems are introduced and briefly discussed. We then describe a compact six degree of freedom parallel mechanism telerobotic system for ultrasound imaging developed by our research team. The long-term goal of this work is to enable remote ultrasound scanning through teleoperation. This parallel mechanism allows for both translation and rotation of an ultrasound probe mounted on the top plate along with force control. Our experimental results confirmed good mechanical system performance with a positioning error of < 1 mm. Phantom experiments by a radiologist showed promising results with good image quality.
Intra-operative ultrasound hand-held strain imaging for the visualization of ablations produced in the liver with a toroidal HIFU transducer: first in vivo results

Energy Technology Data Exchange (ETDEWEB)

Chenot, J; Melodelima, D; N' Djin, W A; Souchon, Remi; Rivoire, M; Chapelon, J Y, E-mail: jeremy.chenot@inserm.f [Inserm, U556, Lyon, F-69003 (France)

2010-06-07

The use of hand-held ultrasound strain imaging for the intra-operative real-time visualization of HIFU (high-intensity focused ultrasound) ablations produced in the liver by a toroidal transducer was investigated. A linear 12 MHz ultrasound imaging probe was used to obtain radiofrequency signals. Using a fast cross-correlation algorithm, strain images were calculated and displayed at 60 frames s{sup -1}, allowing the use of hand-held strain imaging intra-operatively. Fourteen HIFU lesions were produced in four pigs. Intra-operative strain imaging of HIFU ablations in the liver was feasible owing to the high frame rate. The correlation between dimensions measured on gross pathology and dimensions measured on B-mode images and on strain images were R = 0.72 and R = 0.94 respectively. The contrast between ablated and non-ablated tissue was significantly higher (p < 0.05) in the strain images (22 dB) than in the B-mode images (9 dB). Strain images allowed equivalent or improved definition of ablated regions when compared with B-mode images. Real-time intra-operative hand-held strain imaging seems to be a promising complement to conventional B-mode imaging for the guidance of HIFU ablations produced in the liver during an open procedure. These results support that hand-held strain imaging outperforms conventional B-mode ultrasound and could potentially be used for the assessment of thermal therapies.
Ultrafast Ultrasound Imaging With Cascaded Dual-Polarity Waves.

Science.gov (United States)

Zhang, Yang; Guo, Yuexin; Lee, Wei-Ning

2018-04-01

Ultrafast ultrasound imaging using plane or diverging waves, instead of focused beams, has advanced greatly the development of novel ultrasound imaging methods for evaluating tissue functions beyond anatomical information. However, the sonographic signal-to-noise ratio (SNR) of ultrafast imaging remains limited due to the lack of transmission focusing, and thus insufficient acoustic energy delivery. We hereby propose a new ultrafast ultrasound imaging methodology with cascaded dual-polarity waves (CDWs), which consists of a pulse train with positive and negative polarities. A new coding scheme and a corresponding linear decoding process were thereby designed to obtain the recovered signals with increased amplitude, thus increasing the SNR without sacrificing the frame rate. The newly designed CDW ultrafast ultrasound imaging technique achieved higher quality B-mode images than coherent plane-wave compounding (CPWC) and multiplane wave (MW) imaging in a calibration phantom, ex vivo pork belly, and in vivo human back muscle. CDW imaging shows a significant improvement in the SNR (10.71 dB versus CPWC and 7.62 dB versus MW), penetration depth (36.94% versus CPWC and 35.14% versus MW), and contrast ratio in deep regions (5.97 dB versus CPWC and 5.05 dB versus MW) without compromising other image quality metrics, such as spatial resolution and frame rate. The enhanced image qualities and ultrafast frame rates offered by CDW imaging beget great potential for various novel imaging applications.
Quantitative ultrasound and photoacoustic imaging for the assessment of vascular parameters

CERN Document Server

Meiburger, Kristen M

2017-01-01

This book describes the development of quantitative techniques for ultrasound and photoacoustic imaging in the assessment of architectural and vascular parameters. It presents morphological vascular research based on the development of quantitative imaging techniques for the use of clinical B-mode ultrasound images, and preclinical architectural vascular investigations on quantitative imaging techniques for ultrasounds and photoacoustics. The book is divided into two main parts, the first of which focuses on the development and validation of quantitative techniques for the assessment of vascular morphological parameters that can be extracted from B-mode ultrasound longitudinal images of the common carotid artery. In turn, the second part highlights quantitative imaging techniques for assessing the architectural parameters of vasculature that can be extracted from 3D volumes, using both contrast-enhanced ultrasound (CEUS) imaging and photoacoustic imaging without the addition of any contrast agent. Sharing and...
Image registration assessment in radiotherapy image guidance based on control chart monitoring.

Science.gov (United States)

Xia, Wenyao; Breen, Stephen L

2018-04-01

Image guidance with cone beam computed tomography in radiotherapy can guarantee the precision and accuracy of patient positioning prior to treatment delivery. During the image guidance process, operators need to take great effort to evaluate the image guidance quality before correcting a patient's position. This work proposes an image registration assessment method based on control chart monitoring to reduce the effort taken by the operator. According to the control chart plotted by daily registration scores of each patient, the proposed method can quickly detect both alignment errors and image quality inconsistency. Therefore, the proposed method can provide a clear guideline for the operators to identify unacceptable image quality and unacceptable image registration with minimal effort. Experimental results demonstrate that by using control charts from a clinical database of 10 patients undergoing prostate radiotherapy, the proposed method can quickly identify out-of-control signals and find special cause of out-of-control registration events.
WE-B-210-02: The Advent of Ultrafast Imaging in Biomedical Ultrasound

International Nuclear Information System (INIS)

Tanter, M.

2015-01-01

In the last fifteen years, the introduction of plane or diverging wave transmissions rather than line by line scanning focused beams has broken the conventional barriers of ultrasound imaging. By using such large field of view transmissions, the frame rate reaches the theoretical limit of physics dictated by the ultrasound speed and an ultrasonic map can be provided typically in tens of micro-seconds (several thousands of frames per second). Interestingly, this leap in frame rate is not only a technological breakthrough but it permits the advent of completely new ultrasound imaging modes, including shear wave elastography, electromechanical wave imaging, ultrafast doppler, ultrafast contrast imaging, and even functional ultrasound imaging of brain activity (fUltrasound) introducing Ultrasound as an emerging full-fledged neuroimaging modality. At ultrafast frame rates, it becomes possible to track in real time the transient vibrations – known as shear waves – propagating through organs. Such “human body seismology” provides quantitative maps of local tissue stiffness whose added value for diagnosis has been recently demonstrated in many fields of radiology (breast, prostate and liver cancer, cardiovascular imaging, …). Today, Supersonic Imagine company is commercializing the first clinical ultrafast ultrasound scanner, Aixplorer with real time Shear Wave Elastography. This is the first example of an ultrafast Ultrasound approach surpassing the research phase and now widely spread in the clinical medical ultrasound community with an installed base of more than 1000 Aixplorer systems in 54 countries worldwide. For blood flow imaging, ultrafast Doppler permits high-precision characterization of complex vascular and cardiac flows. It also gives ultrasound the ability to detect very subtle blood flow in very small vessels. In the brain, such ultrasensitive Doppler paves the way for fUltrasound (functional ultrasound imaging) of brain activity with unprecedented
WE-B-210-02: The Advent of Ultrafast Imaging in Biomedical Ultrasound

Energy Technology Data Exchange (ETDEWEB)

Tanter, M. [Laboratoire Ondes et Acoustique (France)

2015-06-15

In the last fifteen years, the introduction of plane or diverging wave transmissions rather than line by line scanning focused beams has broken the conventional barriers of ultrasound imaging. By using such large field of view transmissions, the frame rate reaches the theoretical limit of physics dictated by the ultrasound speed and an ultrasonic map can be provided typically in tens of micro-seconds (several thousands of frames per second). Interestingly, this leap in frame rate is not only a technological breakthrough but it permits the advent of completely new ultrasound imaging modes, including shear wave elastography, electromechanical wave imaging, ultrafast doppler, ultrafast contrast imaging, and even functional ultrasound imaging of brain activity (fUltrasound) introducing Ultrasound as an emerging full-fledged neuroimaging modality. At ultrafast frame rates, it becomes possible to track in real time the transient vibrations – known as shear waves – propagating through organs. Such “human body seismology” provides quantitative maps of local tissue stiffness whose added value for diagnosis has been recently demonstrated in many fields of radiology (breast, prostate and liver cancer, cardiovascular imaging, …). Today, Supersonic Imagine company is commercializing the first clinical ultrafast ultrasound scanner, Aixplorer with real time Shear Wave Elastography. This is the first example of an ultrafast Ultrasound approach surpassing the research phase and now widely spread in the clinical medical ultrasound community with an installed base of more than 1000 Aixplorer systems in 54 countries worldwide. For blood flow imaging, ultrafast Doppler permits high-precision characterization of complex vascular and cardiac flows. It also gives ultrasound the ability to detect very subtle blood flow in very small vessels. In the brain, such ultrasensitive Doppler paves the way for fUltrasound (functional ultrasound imaging) of brain activity with unprecedented

Synthetic tracked aperture ultrasound imaging: design, simulation, and experimental evaluation.

Science.gov (United States)

Zhang, Haichong K; Cheng, Alexis; Bottenus, Nick; Guo, Xiaoyu; Trahey, Gregg E; Boctor, Emad M

2016-04-01

Ultrasonography is a widely used imaging modality to visualize anatomical structures due to its low cost and ease of use; however, it is challenging to acquire acceptable image quality in deep tissue. Synthetic aperture (SA) is a technique used to increase image resolution by synthesizing information from multiple subapertures, but the resolution improvement is limited by the physical size of the array transducer. With a large F-number, it is difficult to achieve high resolution in deep regions without extending the effective aperture size. We propose a method to extend the available aperture size for SA-called synthetic tracked aperture ultrasound (STRATUS) imaging-by sweeping an ultrasound transducer while tracking its orientation and location. Tracking information of the ultrasound probe is used to synthesize the signals received at different positions. Considering the practical implementation, we estimated the effect of tracking and ultrasound calibration error to the quality of the final beamformed image through simulation. In addition, to experimentally validate this approach, a 6 degree-of-freedom robot arm was used as a mechanical tracker to hold an ultrasound transducer and to apply in-plane lateral translational motion. Results indicate that STRATUS imaging with robotic tracking has the potential to improve ultrasound image quality.
Windowed time-reversal music technique for super-resolution ultrasound imaging

Science.gov (United States)

Huang, Lianjie; Labyed, Yassin

2018-05-01

Systems and methods for super-resolution ultrasound imaging using a windowed and generalized TR-MUSIC algorithm that divides the imaging region into overlapping sub-regions and applies the TR-MUSIC algorithm to the windowed backscattered ultrasound signals corresponding to each sub-region. The algorithm is also structured to account for the ultrasound attenuation in the medium and the finite-size effects of ultrasound transducer elements.
Tissue Harmonic Synthetic Aperture Ultrasound Imaging

DEFF Research Database (Denmark)

Hemmsen, Martin Christian; Rasmussen, Joachim; Jensen, Jørgen Arendt

2014-01-01

Synthetic aperture sequential beamforming (SASB) and tissue har- monic imaging (THI) are combined to improve the image quality of medical ultrasound imaging. The technique is evaluated in a compar- ative study against dynamic receive focusing (DRF). The objective is to investigate if SASB combined...... with THI improves the image qual- ity compared to DRF-THI. The major benet of SASB is a reduced bandwidth between the probe and processing unit. A BK Medical 2202 Ultraview ultrasound scanner was used to acquire beamformed RF data for oine evaluation. The acquisition was made interleaved between methods......, and data were recorded with and without pulse inversion for tissue harmonic imaging. Data were acquired using a Sound Technol- ogy 192 element convex array transducer from both a wire phantom and a tissue mimicking phantom to investigate spatial resolution and pen- etration. In-vivo scans were also...
Active point out-of-plane ultrasound calibration

Science.gov (United States)

Cheng, Alexis; Guo, Xiaoyu; Zhang, Haichong K.; Kang, Hyunjae; Etienne-Cummings, Ralph; Boctor, Emad M.

2015-03-01

Image-guided surgery systems are often used to provide surgeons with informational support. Due to several unique advantages such as ease of use, real-time image acquisition, and no ionizing radiation, ultrasound is a common intraoperative medical imaging modality used in image-guided surgery systems. To perform advanced forms of guidance with ultrasound, such as virtual image overlays or automated robotic actuation, an ultrasound calibration process must be performed. This process recovers the rigid body transformation between a tracked marker attached to the transducer and the ultrasound image. Point-based phantoms are considered to be accurate, but their calibration framework assumes that the point is in the image plane. In this work, we present the use of an active point phantom and a calibration framework that accounts for the elevational uncertainty of the point. Given the lateral and axial position of the point in the ultrasound image, we approximate a circle in the axial-elevational plane with a radius equal to the axial position. The standard approach transforms all of the imaged points to be a single physical point. In our approach, we minimize the distances between the circular subsets of each image, with them ideally intersecting at a single point. We simulated in noiseless and noisy cases, presenting results on out-of-plane estimation errors, calibration estimation errors, and point reconstruction precision. We also performed an experiment using a robot arm as the tracker, resulting in a point reconstruction precision of 0.64mm.
Ultrasound Vector Flow Imaging: Part II: Parallel Systems

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt; Nikolov, Svetoslav Ivanov; Yu, Alfred C. H.

2016-01-01

The paper gives a review of the current state-of-theart in ultrasound parallel acquisition systems for flow imaging using spherical and plane waves emissions. The imaging methods are explained along with the advantages of using these very fast and sensitive velocity estimators. These experimental...... ultrasound imaging for studying brain function in animals. The paper explains the underlying acquisition and estimation methods for fast 2-D and 3-D velocity imaging and gives a number of examples. Future challenges and the potentials of parallel acquisition systems for flow imaging are also discussed....
Synthetic Aperture Imaging in Medical Ultrasound

DEFF Research Database (Denmark)

Nikolov, Svetoslav; Gammelmark, Kim; Pedersen, Morten

2004-01-01

with high precision, and the imaging is easily extended to real-time 3D scanning. This paper presents the work done at the Center for Fast Ultrasound Imaging in the area of SA imaging. Three areas that benefit from SA imaging are described. Firstly a preliminary in-vivo evaluation comparing conventional B...
Contrast enhanced ultrasound in liver imaging

International Nuclear Information System (INIS)

Nielsen, Michael Bachmann; Bang, Nanna

2004-01-01

Ultrasound contrast agents were originally introduced to enhance the Doppler signals when detecting vessels with low velocity flow or when imaging conditions were sub-optimal. Contrast agents showed additional properties, it was discovered that a parenchymal enhancement phase in the liver followed the enhancement of the blood pool. Contrast agents have made ultrasound scanning more accurate in detection and characterization of focal hepatic lesions and the sensitivity is now comparable with CT and MRI scanning. Further, analysis of the transit time of contrast agent through the liver seems to give information on possible hepatic involvement, not only from focal lesions but also from diffuse benign parenchymal disease. The first ultrasound contrast agents were easily destroyed by the energy from the sound waves but newer agents have proved to last for longer time and hereby enable real-time scanning and make contrast enhancement suitable for interventional procedures such as biopsies and tissue ablation. Also, in monitoring the effect of tumour treatment contrast agents have been useful. A brief overview is given on some possible applications and on different techniques using ultrasound contrast agents in liver imaging. At present, the use of an ultrasound contrast agent that allows real-time scanning with low mechanical index is to be preferred
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...
Accelerated Air-coupled Ultrasound Imaging of Wood Using Compressed Sensing

Directory of Open Access Journals (Sweden)

Yiming Fang

2015-12-01

Full Text Available Air-coupled ultrasound has shown excellent sensitivity and specificity for the nondestructive imaging of wood-based material. However, it is time-consuming, due to the high scanning density limited by the Nyquist law. This study investigated the feasibility of applying compressed sensing techniques to air-coupled ultrasound imaging, aiming to reduce the number of scanning lines and then accelerate the imaging. Firstly, an undersampled scanning strategy specified by a random binary matrix was proposed to address the limitation of the compressed sensing framework. The undersampled scanning can be easily implemented, while only minor modification was required for the existing imaging system. Then, discrete cosine transform was selected experimentally as the representation basis. Finally, orthogonal matching pursuit algorithm was utilized to reconstruct the wood images. Experiments on three real air-coupled ultrasound images indicated the potential of the present method to accelerate air-coupled ultrasound imaging of wood. The same quality of ACU images can be obtained with scanning time cut in half.
Multiplane wave imaging increases signal-to-noise ratio in ultrafast ultrasound imaging

International Nuclear Information System (INIS)

Tiran, Elodie; Deffieux, Thomas; Correia, Mafalda; Maresca, David; Osmanski, Bruno-Felix; Pernot, Mathieu; Tanter, Mickael; Sieu, Lim-Anna; Bergel, Antoine; Cohen, Ivan

2015-01-01

Ultrafast imaging using plane or diverging waves has recently enabled new ultrasound imaging modes with improved sensitivity and very high frame rates. Some of these new imaging modalities include shear wave elastography, ultrafast Doppler, ultrafast contrast-enhanced imaging and functional ultrasound imaging. Even though ultrafast imaging already encounters clinical success, increasing even more its penetration depth and signal-to-noise ratio for dedicated applications would be valuable.Ultrafast imaging relies on the coherent compounding of backscattered echoes resulting from successive tilted plane waves emissions; this produces high-resolution ultrasound images with a trade-off between final frame rate, contrast and resolution. In this work, we introduce multiplane wave imaging, a new method that strongly improves ultrafast images signal-to-noise ratio by virtually increasing the emission signal amplitude without compromising the frame rate. This method relies on the successive transmissions of multiple plane waves with differently coded amplitudes and emission angles in a single transmit event. Data from each single plane wave of increased amplitude can then be obtained, by recombining the received data of successive events with the proper coefficients.The benefits of multiplane wave for B-mode, shear wave elastography and ultrafast Doppler imaging are experimentally demonstrated. Multiplane wave with 4 plane waves emissions yields a 5.8 ± 0.5 dB increase in signal-to-noise ratio and approximately 10 mm in penetration in a calibrated ultrasound phantom (0.7 d MHz −1 cm −1 ). In shear wave elastography, the same multiplane wave configuration yields a 2.07 ± 0.05 fold reduction of the particle velocity standard deviation and a two-fold reduction of the shear wave velocity maps standard deviation. In functional ultrasound imaging, the mapping of cerebral blood volume results in a 3 to 6 dB increase of the contrast-to-noise ratio in
Virtual ultrasound sources in high-resolution ultrasound imaging

DEFF Research Database (Denmark)

Nikolov, Svetoslav; Jensen, Jørgen Arendt

2002-01-01

beamforming procedure for 3D ultrasound imaging. The position of the virtual source, and the created waveform are investigated with simulation, and with pulse-echo measurements. There is good agreement between the estimated wavefront and the theoretically tted one. Several examples of the use of virtual...... source elements are considered. Using SAF on data acquired for a conventional linear array imaging improves the penetration depth for the particular imaging situation from 80 to 110 mm. The independent use of virtual source elements in the elevation plane decreases the respective size of the point spread...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... not use ionizing radiation, has no known harmful effects, and is particularly valuable for ... is no radiation exposure to the patient. Because ultrasound images are captured ...
MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

International Nuclear Information System (INIS)

2015-01-01

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS
MO-AB-210-00: Diagnostic Ultrasound Imaging Quality Control and High Intensity Focused Ultrasound Therapy Hands-On Workshop

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-06-15

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

Science.gov (United States)

Bayani, Azadeh; Langarizadeh, Mostafa; Radmard, Amir Reza; Nejad, Ahmadreza Farzaneh

2016-12-01

Liver ultrasound images are so common and are applied so often to diagnose diffuse liver diseases like fatty liver. However, the low quality of such images makes it difficult to analyze them and diagnose diseases. The purpose of this study, therefore, is to improve the contrast and quality of liver ultrasound images. In this study, a number of image contrast enhancement algorithms which are based on fuzzy logic were applied to liver ultrasound images - in which the view of kidney is observable - using Matlab2013b to improve the image contrast and quality which has a fuzzy definition; just like image contrast improvement algorithms using a fuzzy intensification operator, contrast improvement algorithms applying fuzzy image histogram hyperbolization, and contrast improvement algorithms by fuzzy IF-THEN rules. With the measurement of Mean Squared Error and Peak Signal to Noise Ratio obtained from different images, fuzzy methods provided better results, and their implementation - compared with histogram equalization method - led both to the improvement of contrast and visual quality of images and to the improvement of liver segmentation algorithms results in images. Comparison of the four algorithms revealed the power of fuzzy logic in improving image contrast compared with traditional image processing algorithms. Moreover, contrast improvement algorithm based on a fuzzy intensification operator was selected as the strongest algorithm considering the measured indicators. This method can also be used in future studies on other ultrasound images for quality improvement and other image processing and analysis applications.
Micromachined Integrated Transducers for Ultrasound Imaging

DEFF Research Database (Denmark)

la Cour, Mette Funding

The purpose of this project is to develop capacitive micromachined ultrasonic transducers (CMUTs) for medical imaging. Medical ultrasound transducers used today are fabricated using piezoelectric materials and bulk processing. To fabricate transducers capable of delivering a higher imaging...
Despeckle filtering for ultrasound imaging and video II selected applications

CERN Document Server

Loizou, Christos P

2015-01-01

In ultrasound imaging and video visual perception is hindered by speckle multiplicative noise that degrades the quality. Noise reduction is therefore essential for improving the visual observation quality or as a pre-processing step for further automated analysis, such as image/video segmentation, texture analysis and encoding in ultrasound imaging and video. The goal of the first book (book 1 of 2 books) was to introduce the problem of speckle in ultrasound image and video as well as the theoretical background, algorithmic steps, and the MatlabTM for the following group of despeckle filters:
Real-time image fusion involving diagnostic ultrasound

DEFF Research Database (Denmark)

Ewertsen, Caroline; Săftoiu, Adrian; Gruionu, Lucian G

2013-01-01

The aim of our article is to give an overview of the current and future possibilities of real-time image fusion involving ultrasound. We present a review of the existing English-language peer-reviewed literature assessing this technique, which covers technical solutions (for ultrasound...
Time reversal and phase coherent music techniques for super-resolution ultrasound imaging

Science.gov (United States)

Huang, Lianjie; Labyed, Yassin

2018-05-01

Systems and methods for super-resolution ultrasound imaging using a windowed and generalized TR-MUSIC algorithm that divides the imaging region into overlapping sub-regions and applies the TR-MUSIC algorithm to the windowed backscattered ultrasound signals corresponding to each sub-region. The algorithm is also structured to account for the ultrasound attenuation in the medium and the finite-size effects of ultrasound transducer elements. A modified TR-MUSIC imaging algorithm is used to account for ultrasound scattering from both density and compressibility contrasts. The phase response of ultrasound transducer elements is accounted for in a PC-MUSIC system.
Standardized ultrasound templates for diagnosing appendicitis reduce annual imaging costs.

Science.gov (United States)

Nordin, Andrew B; Sales, Stephen; Nielsen, Jason W; Adler, Brent; Bates, David Gregory; Kenney, Brian

2018-01-01

Ultrasound is preferred over computed tomography (CT) for diagnosing appendicitis in children to avoid undue radiation exposure. We previously reported our experience in instituting a standardized appendicitis ultrasound template, which decreased CT rates by 67.3%. In this analysis, we demonstrate the ongoing cost savings associated with using this template. Retrospective chart review for the time period preceding template implementation (June 2012-September 2012) was combined with prospective review through December 2015 for all patients in the emergency department receiving diagnostic imaging for appendicitis. The type of imaging was recorded, and imaging rates and ultrasound test statistics were calculated. Estimated annual imaging costs based on pretemplate ultrasound and CT utilization rates were compared with post-template annual costs to calculate annual and cumulative savings. In the pretemplate period, ultrasound and CT rates were 80.2% and 44.3%, respectively, resulting in a combined annual cost of $300,527.70. Similar calculations were performed for each succeeding year, accounting for changes in patient volume. Using pretemplate rates, our projected 2015 imaging cost was $371,402.86; however, our ultrasound rate had increased to 98.3%, whereas the CT rate declined to 9.6%, yielding an annual estimated cost of $224,853.00 and a savings of $146,549.86. Since implementation, annual savings have steadily increased for a cumulative cost savings of $336,683.83. Standardizing ultrasound reports for appendicitis not only reduces the use of CT scans and the associated radiation exposure but also decreases annual imaging costs despite increased numbers of imaging studies. Continued cost reduction may be possible by using diagnostic algorithms. Copyright © 2017 Elsevier Inc. All rights reserved.

Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... and movement of the body's internal organs, as well as blood flowing through blood vessels. Ultrasound imaging is a noninvasive medical test that helps physicians diagnose and treat medical conditions. ...
Dual-Modality PET/Ultrasound imaging of the Prostate

Energy Technology Data Exchange (ETDEWEB)

Huber, Jennifer S.; Moses, William W.; Pouliot, Jean; Hsu, I.C.

2005-11-11

Functional imaging with positron emission tomography (PET)will detect malignant tumors in the prostate and/or prostate bed, as well as possibly help determine tumor ''aggressiveness''. However, the relative uptake in a prostate tumor can be so great that few other anatomical landmarks are visible in a PET image. Ultrasound imaging with a transrectal probe provides anatomical detail in the prostate region that can be co-registered with the sensitive functional information from the PET imaging. Imaging the prostate with both PET and transrectal ultrasound (TRUS) will help determine the location of any cancer within the prostate region. This dual-modality imaging should help provide better detection and treatment of prostate cancer. LBNL has built a high performance positron emission tomograph optimized to image the prostate.Compared to a standard whole-body PET camera, our prostate-optimized PET camera has the same sensitivity and resolution, less backgrounds and lower cost. We plan to develop the hardware and software tools needed for a validated dual PET/TRUS prostate imaging system. We also plan to develop dual prostate imaging with PET and external transabdominal ultrasound, in case the TRUS system is too uncomfortable for some patients. We present the design and intended clinical uses for these dual imaging systems.
Dual-Modality PET/Ultrasound imaging of the Prostate

International Nuclear Information System (INIS)

Huber, Jennifer S.; Moses, William W.; Pouliot, Jean; Hsu, I.C.

2005-01-01

Functional imaging with positron emission tomography (PET)will detect malignant tumors in the prostate and/or prostate bed, as well as possibly help determine tumor ''aggressiveness''. However, the relative uptake in a prostate tumor can be so great that few other anatomical landmarks are visible in a PET image. Ultrasound imaging with a transrectal probe provides anatomical detail in the prostate region that can be co-registered with the sensitive functional information from the PET imaging. Imaging the prostate with both PET and transrectal ultrasound (TRUS) will help determine the location of any cancer within the prostate region. This dual-modality imaging should help provide better detection and treatment of prostate cancer. LBNL has built a high performance positron emission tomograph optimized to image the prostate.Compared to a standard whole-body PET camera, our prostate-optimized PET camera has the same sensitivity and resolution, less backgrounds and lower cost. We plan to develop the hardware and software tools needed for a validated dual PET/TRUS prostate imaging system. We also plan to develop dual prostate imaging with PET and external transabdominal ultrasound, in case the TRUS system is too uncomfortable for some patients. We present the design and intended clinical uses for these dual imaging systems
2D array transducers for real-time 3D ultrasound guidance of interventional devices

Science.gov (United States)

Light, Edward D.; Smith, Stephen W.

2009-02-01

We describe catheter ring arrays for real-time 3D ultrasound guidance of devices such as vascular grafts, heart valves and vena cava filters. We have constructed several prototypes operating at 5 MHz and consisting of 54 elements using the W.L. Gore & Associates, Inc. micro-miniature ribbon cables. We have recently constructed a new transducer using a braided wiring technology from Precision Interconnect. This transducer consists of 54 elements at 4.8 MHz with pitch of 0.20 mm and typical -6 dB bandwidth of 22%. In all cases, the transducer and wiring assembly were integrated with an 11 French catheter of a Cook Medical deployment device for vena cava filters. Preliminary in vivo and in vitro testing is ongoing including simultaneous 3D ultrasound and x-ray fluoroscopy.
Simulation of ultrasound backscatter images from fish

DEFF Research Database (Denmark)

Pham, An Hoai

2011-01-01

The objective of this work is to investigate ultrasound (US) backscatter in the MHz range from fis to develop a realistic and reliable simulation model. The long term objective of the work is to develop the needed signal processing for fis species differentiation using US. In in-vitro experiments...... is 10 MHz and the Full Width at Half Maximum (FWHM) at the focus point is 0.54 mm in the lateral direction. The transducer model in Field II was calibrated using a wire phantom to validate the simulated point spread function. The inputs to the simulation were the CT image data of the fis converted......, a cod (Gadus morhua) was scanned with both a BK Medical ProFocus 2202 ultrasound scanner and a Toshiba Aquilion ONE computed tomography (CT) scanner. The US images of the fis were compared with US images created using the ultrasound simulation program Field II. The center frequency of the transducer...
The Lunula: An ultrasound imaging approach

International Nuclear Information System (INIS)

Choi, Soo Jung; Shin, Myung Jin; Kim, Sung Moon; Ahn, Joong Mo

2001-01-01

The lunula is the white, half-moon-shaped area seen on some, but not all nails. Usually the lunula is the topographic marker of the distal part of the nail matrix, and known to have the ability of nail production. Ultrasonographic imaging of the lunula has not been reported before. This study was undertaken to demonstrate normal ultrasonographic features of the lunula. Ultrasonographic examination of the lunula was performed in the right thumb of 20 healthy volunteers (10M, 10F, mean age 30, range 26-36 years) with a real-time, high-resolution ultrasound unit (Sequoia 512, Acuson, Mountain view, CA, USA) with 8-15 MHz linear transducers. Gray scale color, and special Doppler imagings were performed with longitudinal scanning. The lunula was not seen inspection in three of the 20 volunteers. The mean size of the lunula in the other 17 volumteen was 3.31 ± 1.24 mm (range 2-6.2 mm). Gray scale ultrasound imaging showed the lunula; ovoid shaped hypo-echoic zone in proximal fingernail in 18 of 20 volunteers (mean size, 6.74 ± 0.98 mm, range 5-8.8 mm). In two of 20 volunteers, the lunula was indistinct on gray scale ultrasound examination. However, all lunula were identifiable on color Doppler imaging by detecting vascularity within the lunula. Spectral wave pattern of the lunula was a bi-directional pulsatile wave. Peak velocity was within 5-15 m/sec (mean 8 m/sec). The lunula is identifiable on ultrasound examination as a hyper-vascular, ovoid shaped, hypo-echoic zone in proximal fingernail. This normal structure should not be misinterpreted as an abnormal sub-ungual lesion.
Super-Resolution Image Reconstruction Applied to Medical Ultrasound

Science.gov (United States)

Ellis, Michael

Ultrasound is the preferred imaging modality for many diagnostic applications due to its real-time image reconstruction and low cost. Nonetheless, conventional ultrasound is not used in many applications because of limited spatial resolution and soft tissue contrast. Most commercial ultrasound systems reconstruct images using a simple delay-and-sum architecture on receive, which is fast and robust but does not utilize all information available in the raw data. Recently, more sophisticated image reconstruction methods have been developed that make use of far more information in the raw data to improve resolution and contrast. One such method is the Time-Domain Optimized Near-Field Estimator (TONE), which employs a maximum a priori estimation to solve a highly underdetermined problem, given a well-defined system model. TONE has been shown to significantly improve both the contrast and resolution of ultrasound images when compared to conventional methods. However, TONE's lack of robustness to variations from the system model and extremely high computational cost hinder it from being readily adopted in clinical scanners. This dissertation aims to reduce the impact of TONE's shortcomings, transforming it from an academic construct to a clinically viable image reconstruction algorithm. By altering the system model from a collection of individual hypothetical scatterers to a collection of weighted, diffuse regions, dTONE is able to achieve much greater robustness to modeling errors. A method for efficient parallelization of dTONE is presented that reduces reconstruction time by more than an order of magnitude with little loss in image fidelity. An alternative reconstruction algorithm, called qTONE, is also developed and is able to reduce reconstruction times by another two orders of magnitude while simultaneously improving image contrast. Each of these methods for improving TONE are presented, their limitations are explored, and all are used in concert to reconstruct in
Enhanced ultrasound for advanced diagnostics, ultrasound tomography for volume limb imaging and prosthetic fitting

Science.gov (United States)

Anthony, Brian W.

2016-04-01

Ultrasound imaging methods hold the potential to deliver low-cost, high-resolution, operator-independent and nonionizing imaging systems - such systems couple appropriate algorithms with imaging devices and techniques. The increasing demands on general practitioners motivate us to develop more usable and productive diagnostic imaging equipment. Ultrasound, specifically freehand ultrasound, is a low cost and safe medical imaging technique. It doesn't expose a patient to ionizing radiation. Its safety and versatility make it very well suited for the increasing demands on general practitioners, or for providing improved medical care in rural regions or the developing world. However it typically suffers from sonographer variability; we will discuss techniques to address user variability. We also discuss our work to combine cylindrical scanning systems with state of the art inversion algorithms to deliver ultrasound systems for imaging and quantifying limbs in 3-D in vivo. Such systems have the potential to track the progression of limb health at a low cost and without radiation exposure, as well as, improve prosthetic socket fitting. Current methods of prosthetic socket fabrication remain subjective and ineffective at creating an interface to the human body that is both comfortable and functional. Though there has been recent success using methods like magnetic resonance imaging and biomechanical modeling, a low-cost, streamlined, and quantitative process for prosthetic cup design and fabrication has not been fully demonstrated. Medical ultrasonography may inform the design process of prosthetic sockets in a more objective manner. This keynote talk presents the results of progress in this area.
Imaging of Groin Pain: Magnetic Resonance and Ultrasound Imaging Features.

Science.gov (United States)

Lee, Susan C; Endo, Yoshimi; Potter, Hollis G

Evaluation of groin pain in athletes may be challenging as pain is typically poorly localized and the pubic symphyseal region comprises closely approximated tendons and muscles. As such, magnetic resonance imaging (MRI) and ultrasound (US) may help determine the etiology of groin pain. A PubMed search was performed using the following search terms: ultrasound, magnetic resonance imaging, sports hernia, athletic pubalgia, and groin pain. Date restrictions were not placed on the literature search. Clinical review. Level 4. MRI is sensitive in diagnosing pathology in groin pain. Not only can MRI be used to image rectus abdominis/adductor longus aponeurosis and pubic bone pathology, but it can also evaluate other pathology within the hip and pelvis. MRI is especially helpful when groin pain is poorly localized. Real-time capability makes ultrasound useful in evaluating the pubic symphyseal region, as it can be used for evaluation and treatment. MRI and US are valuable in diagnosing pathology in athletes with groin pain, with the added utility of treatment using US-guided intervention. Strength-of Recommendation Taxonomy: C.
The evaluation of radiologic methods for access guidance in percutaneous nephrolithotomy

DEFF Research Database (Denmark)

Breda, Alberto; Territo, Angelo; Scoffone, Cesare

2018-01-01

is controversial? A systematic review of the literature was performed comparing image guidance modalities for obtaining access in PNL. Evidence acquisition and synthesis: A PubMed, Scopus and Cochrane search for peer-reviewed studies was performed using the keywords "ultrasound" AND "fluoroscopy" AND "Percutaneous...
Comparison of different reconstruction algorithms for three-dimensional ultrasound imaging in a neurosurgical setting.

Science.gov (United States)

Miller, D; Lippert, C; Vollmer, F; Bozinov, O; Benes, L; Schulte, D M; Sure, U

2012-09-01

Freehand three-dimensional ultrasound imaging (3D-US) is increasingly used in image-guided surgery. During image acquisition, a set of B-scans is acquired that is distributed in a non-parallel manner over the area of interest. Reconstructing these images into a regular array allows 3D visualization. However, the reconstruction process may introduce artefacts and may therefore reduce image quality. The aim of the study is to compare different algorithms with respect to image quality and diagnostic value for image guidance in neurosurgery. 3D-US data sets were acquired during surgery of various intracerebral lesions using an integrated ultrasound-navigation device. They were stored for post-hoc evaluation. Five different reconstruction algorithms, a standard multiplanar reconstruction with interpolation (MPR), a pixel nearest neighbour method (PNN), a voxel nearest neighbour method (VNN) and two voxel based distance-weighted algorithms (VNN2 and DW) were tested with respect to image quality and artefact formation. The capability of the algorithm to fill gaps within the sample volume was investigated and a clinical evaluation with respect to the diagnostic value of the reconstructed images was performed. MPR was significantly worse than the other algorithms in filling gaps. In an image subtraction test, VNN2 and DW reliably reconstructed images even if large amounts of data were missing. However, the quality of the reconstruction improved, if data acquisition was performed in a structured manner. When evaluating the diagnostic value of reconstructed axial, sagittal and coronal views, VNN2 and DW were judged to be significantly better than MPR and VNN. VNN2 and DW could be identified as robust algorithms that generate reconstructed US images with a high diagnostic value. These algorithms improve the utility and reliability of 3D-US imaging during intraoperative navigation. Copyright © 2012 John Wiley & Sons, Ltd.
MO-AB-210-02: Ultrasound Imaging and Therapy-Hands On Workshop

International Nuclear Information System (INIS)

Sammet, S.

2015-01-01

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS
MO-AB-210-01: Ultrasound Imaging and Therapy-Hands On Workshop

International Nuclear Information System (INIS)

Lu, Z.

2015-01-01

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS
MO-AB-210-02: Ultrasound Imaging and Therapy-Hands On Workshop

Energy Technology Data Exchange (ETDEWEB)

Sammet, S. [University of Chicago Medical Center (United States)

2015-06-15

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS
MO-AB-210-01: Ultrasound Imaging and Therapy-Hands On Workshop

Energy Technology Data Exchange (ETDEWEB)

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

2015-06-15

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

Science.gov (United States)

Prada, Francesco; Del Bene, Massimiliano; Moiraghi, Alessandro; Casali, Cecilia; Legnani, Federico Giuseppe; Saladino, Andrea; Perin, Alessandro; Vetrano, Ignazio Gaspare; Mattei, Luca; Richetta, Carla; Saini, Marco; DiMeco, Francesco

2015-01-01

The main goal in meningioma surgery is to achieve complete tumor removal, when possible, while improving or preserving patient neurological functions. Intraoperative imaging guidance is one fundamental tool for such achievement. In this regard, intra-operative ultrasound (ioUS) is a reliable solution to obtain real-time information during surgery and it has been applied in many different aspect of neurosurgery. In the last years, different ioUS modalities have been described: B-mode, Fusion Imaging with pre-operative acquired MRI, Doppler, contrast enhanced ultrasound (CEUS), and elastosonography. In this paper, we present our US based multimodal approach in meningioma surgery. We describe all the most relevant ioUS modalities and their intraoperative application to obtain precise and specific information regarding the lesion for a tailored approach in meningioma surgery. For each modality, we perform a review of the literature accompanied by a pictorial essay based on our routinely use of ioUS for meningioma resection.
Real-Time Implementation of Medical Ultrasound Strain Imaging System

International Nuclear Information System (INIS)

Jeong, Mok Kun; Kwon, Sung Jae; Bae, Moo Ho

2008-01-01

Strain imaging in a medical ultrasound imaging system can differentiate the cancer or tumor in a lesion that is stiffer than the surrounding tissue. In this paper, a strain imaging technique using quasistatic compression is implemented that estimates the displacement between pre- and postcompression ultrasound echoes and obtains strain by differentiating it in the spatial direction. Displacements are computed from the phase difference of complex baseband signals obtained using their autocorrelation, and errors associated with converting the phase difference into time or distance are compensated for by taking into the center frequency variation. Also, to reduce the effect of operator's hand motion, the displacements of all scanlines are normalized with the result that satisfactory strain image quality has been obtained. These techniques have been incorporated into implementing a medical ultrasound strain imaging system that operates in real time.
Improving the Image Quality of Synthetic Transmit Aperture Ultrasound Images - Achieving Real-Time In-Vivo Imaging

DEFF Research Database (Denmark)

Gammelmark, Kim

in-vivo experiments, showed, that TMS imaging can increase the SNR by as much as 17 dB compared to the traditional imaging techniques, which improves the in-vivo image quality to a highly competitive level. An in-vivo evaluation of convex array TMS imaging for abdominal imaging applications......-vivo imaging, and that the obtained image quality is highly competitive with the techniques applied in current medical ultrasound scanners. Hereby, the goals of the PhD have been successfully achieved.......Synthetic transmit aperture (STA) imaging has the potential to increase the image quality of medical ultrasound images beyond the levels obtained by conventional imaging techniques (linear, phased, and convex array imaging). Currently, however, in-vivo applications of STA imaging is limited...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Children's (Pediatric) Ultrasound - Abdomen ...
Processed images in human perception: A case study in ultrasound breast imaging

Energy Technology Data Exchange (ETDEWEB)

Yap, Moi Hoon [Department of Computer Science, Loughborough University, FH09, Ergonomics and Safety Research Institute, Holywell Park (United Kingdom)], E-mail: M.H.Yap@lboro.ac.uk; Edirisinghe, Eran [Department of Computer Science, Loughborough University, FJ.05, Garendon Wing, Holywell Park, Loughborough LE11 3TU (United Kingdom); Bez, Helmut [Department of Computer Science, Loughborough University, Room N.2.26, Haslegrave Building, Loughborough University, Loughborough LE11 3TU (United Kingdom)

2010-03-15

Two main research efforts in early detection of breast cancer include the development of software tools to assist radiologists in identifying abnormalities and the development of training tools to enhance their skills. Medical image analysis systems, widely known as Computer-Aided Diagnosis (CADx) systems, play an important role in this respect. Often it is important to determine whether there is a benefit in including computer-processed images in the development of such software tools. In this paper, we investigate the effects of computer-processed images in improving human performance in ultrasound breast cancer detection (a perceptual task) and classification (a cognitive task). A survey was conducted on a group of expert radiologists and a group of non-radiologists. In our experiments, random test images from a large database of ultrasound images were presented to subjects. In order to gather appropriate formal feedback, questionnaires were prepared to comment on random selections of original images only, and on image pairs consisting of original images displayed alongside computer-processed images. We critically compare and contrast the performance of the two groups according to perceptual and cognitive tasks. From a Receiver Operating Curve (ROC) analysis, we conclude that the provision of computer-processed images alongside the original ultrasound images, significantly improve the perceptual tasks of non-radiologists but only marginal improvements are shown in the perceptual and cognitive tasks of the group of expert radiologists.

Processed images in human perception: A case study in ultrasound breast imaging

International Nuclear Information System (INIS)

Yap, Moi Hoon; Edirisinghe, Eran; Bez, Helmut

2010-01-01

Two main research efforts in early detection of breast cancer include the development of software tools to assist radiologists in identifying abnormalities and the development of training tools to enhance their skills. Medical image analysis systems, widely known as Computer-Aided Diagnosis (CADx) systems, play an important role in this respect. Often it is important to determine whether there is a benefit in including computer-processed images in the development of such software tools. In this paper, we investigate the effects of computer-processed images in improving human performance in ultrasound breast cancer detection (a perceptual task) and classification (a cognitive task). A survey was conducted on a group of expert radiologists and a group of non-radiologists. In our experiments, random test images from a large database of ultrasound images were presented to subjects. In order to gather appropriate formal feedback, questionnaires were prepared to comment on random selections of original images only, and on image pairs consisting of original images displayed alongside computer-processed images. We critically compare and contrast the performance of the two groups according to perceptual and cognitive tasks. From a Receiver Operating Curve (ROC) analysis, we conclude that the provision of computer-processed images alongside the original ultrasound images, significantly improve the perceptual tasks of non-radiologists but only marginal improvements are shown in the perceptual and cognitive tasks of the group of expert radiologists.
Design and development of an ultrasound calibration phantom and system

Science.gov (United States)

Cheng, Alexis; Ackerman, Martin K.; Chirikjian, Gregory S.; Boctor, Emad M.

2014-03-01

Image-guided surgery systems are often used to provide surgeons with informational support. Due to several unique advantages such as ease of use, real-time image acquisition, and no ionizing radiation, ultrasound is a common medical imaging modality used in image-guided surgery systems. To perform advanced forms of guidance with ultrasound, such as virtual image overlays or automated robotic actuation, an ultrasound calibration process must be performed. This process recovers the rigid body transformation between a tracked marker attached to the ultrasound transducer and the ultrasound image. A phantom or model with known geometry is also required. In this work, we design and test an ultrasound calibration phantom and software. The two main considerations in this work are utilizing our knowledge of ultrasound physics to design the phantom and delivering an easy to use calibration process to the user. We explore the use of a three-dimensional printer to create the phantom in its entirety without need for user assembly. We have also developed software to automatically segment the three-dimensional printed rods from the ultrasound image by leveraging knowledge about the shape and scale of the phantom. In this work, we present preliminary results from using this phantom to perform ultrasound calibration. To test the efficacy of our method, we match the projection of the points segmented from the image to the known model and calculate a sum squared difference between each point for several combinations of motion generation and filtering methods. The best performing combination of motion and filtering techniques had an error of 1.56 mm and a standard deviation of 1.02 mm.
Line fiducial material and thickness considerations for ultrasound calibration

Science.gov (United States)

Ameri, Golafsoun; McLeod, A. J.; Baxter, John S. H.; Chen, Elvis C. S.; Peters, Terry M.

2015-03-01

Ultrasound calibration is a necessary procedure in many image-guided interventions, relating the position of tools and anatomical structures in the ultrasound image to a common coordinate system. This is a necessary component of augmented reality environments in image-guided interventions as it allows for a 3D visualization where other surgical tools outside the imaging plane can be found. Accuracy of ultrasound calibration fundamentally affects the total accuracy of this interventional guidance system. Many ultrasound calibration procedures have been proposed based on a variety of phantom materials and geometries. These differences lead to differences in representation of the phantom on the ultrasound image which subsequently affect the ability to accurately and automatically segment the phantom. For example, taut wires are commonly used as line fiducials in ultrasound calibration. However, at large depths or oblique angles, the fiducials appear blurred and smeared in ultrasound images making it hard to localize their cross-section with the ultrasound image plane. Intuitively, larger diameter phantoms with lower echogenicity are more accurately segmented in ultrasound images in comparison to highly reflective thin phantoms. In this work, an evaluation of a variety of calibration phantoms with different geometrical and material properties for the phantomless calibration procedure was performed. The phantoms used in this study include braided wire, plastic straws, and polyvinyl alcohol cryogel tubes with different diameters. Conventional B-mode and synthetic aperture images of the phantoms at different positions were obtained. The phantoms were automatically segmented from the ultrasound images using an ellipse fitting algorithm, the centroid of which is subsequently used as a fiducial for calibration. Calibration accuracy was evaluated for these procedures based on the leave-one-out target registration error. It was shown that larger diameter phantoms with lower
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... a follow-up exam is done because a potential abnormality needs further evaluation with additional views or ... of soft tissues that do not show up well on x-ray images. Ultrasound provides real-time ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... need to be returned to the transducer for analysis. top of page This page was reviewed on ... using ultrasound. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... children. Preparation will depend on the type of examination. Ask your doctor if there are specific instructions ... those sound waves to create an image. Ultrasound examinations do not use ionizing radiation (as used in ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... video display screen and a transducer that is used to do the scanning. The transducer is a ... the body. The principles are similar to sonar used by boats and submarines. The ultrasound image is ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... for traumatic injury, appendicitis is the most common reason for emergency abdominal surgery. Ultrasound imaging can also: ... be necessary. Your doctor will explain the exact reason why another exam is requested. Sometimes a follow- ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... kidneys. top of page What are some common uses of the procedure? Abdominal ultrasound imaging is performed ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... various body organs such as the liver or kidneys. top of page What are some common uses ... appendix stomach/ pylorus liver gallbladder spleen pancreas intestines kidneys bladder testicles ovaries uterus Abdominal ultrasound images can ...
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... echoes from the tissues in the body. The principles are similar to sonar used by boats and ... work? Ultrasound imaging is based on the same principles involved in the sonar used by bats, ships ...
Opto-ultrasound imaging in vivo in deep tissue

International Nuclear Information System (INIS)

Si, Ke; YanXu; Zheng, Yao; Zhu, Xinpei; Gong, Wei

2016-01-01

It is of keen importance of deep tissue imaging with high resolution in vivo. Here we present an opto-ultrasound imaging method which utilizes an ultrasound to confine the laser pulse in a very tiny spot as a guide star. The results show that the imaging depth is 2mm with a resolution of 10um. Meanwhile, the excitation power we used is less than 2mW, which indicates that our methods can be applied in vivo without optical toxicity and optical bleaching due to the excitation power. (paper)
Implementation of Synthetic Aperture Imaging in Medical Ultrasound

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt; Kortbek, Jacob; Nikolov, Svetoslav

2010-01-01

The main advantage of medical ultrasound imaging is its real time capability, which makes it possible to visualize dynamic structures in the human body. Real time synthetic aperture imaging puts very high demands on the hardware, which currently cannot be met. A method for reducing the number...... of calculations and still retain the many advantages of SA imaging is described. It consists of a dual stage beamformer, where the first can be a simple fixed focus analog beamformer and the second an ordinary digital ultrasound beamformer. The performance and constrictions of the approach is described....
Intra-operative ultrasound-based augmented reality guidance for laparoscopic surgery.

Science.gov (United States)

Singla, Rohit; Edgcumbe, Philip; Pratt, Philip; Nguan, Christopher; Rohling, Robert

2017-10-01

In laparoscopic surgery, the surgeon must operate with a limited field of view and reduced depth perception. This makes spatial understanding of critical structures difficult, such as an endophytic tumour in a partial nephrectomy. Such tumours yield a high complication rate of 47%, and excising them increases the risk of cutting into the kidney's collecting system. To overcome these challenges, an augmented reality guidance system is proposed. Using intra-operative ultrasound, a single navigation aid, and surgical instrument tracking, four augmentations of guidance information are provided during tumour excision. Qualitative and quantitative system benefits are measured in simulated robot-assisted partial nephrectomies. Robot-to-camera calibration achieved a total registration error of 1.0 ± 0.4 mm while the total system error is 2.5 ± 0.5 mm. The system significantly reduced healthy tissue excised from an average (±standard deviation) of 30.6 ± 5.5 to 17.5 ± 2.4 cm 3 ( p < 0.05) and reduced the depth from the tumor underside to cut from an average (±standard deviation) of 10.2 ± 4.1 to 3.3 ± 2.3 mm ( p < 0.05). Further evaluation is required in vivo, but the system has promising potential to reduce the amount of healthy parenchymal tissue excised.
Trans-Stent B-Mode Ultrasound and Passive Cavitation Imaging.

Science.gov (United States)

Haworth, Kevin J; Raymond, Jason L; Radhakrishnan, Kirthi; Moody, Melanie R; Huang, Shao-Ling; Peng, Tao; Shekhar, Himanshu; Klegerman, Melvin E; Kim, Hyunggun; McPherson, David D; Holland, Christy K

2016-02-01

Angioplasty and stenting of a stenosed artery enable acute restoration of blood flow. However, restenosis or a lack of re-endothelization can subsequently occur depending on the stent type. Cavitation-mediated drug delivery is a potential therapy for these conditions, but requires that particular types of cavitation be induced by ultrasound insonation. Because of the heterogeneity of tissue and stochastic nature of cavitation, feedback mechanisms are needed to determine whether the sustained bubble activity is induced. The objective of this study was to determine the feasibility of passive cavitation imaging through a metal stent in a flow phantom and an animal model. In this study, an endovascular stent was deployed in a flow phantom and in porcine femoral arteries. Fluorophore-labeled echogenic liposomes, a theragnostic ultrasound contrast agent, were injected proximal to the stent. Cavitation images were obtained by passively recording and beamforming the acoustic emissions from echogenic liposomes insonified with a low-frequency (500 kHz) transducer. In vitro experiments revealed that the signal-to-noise ratio for detecting stable cavitation activity through the stent was greater than 8 dB. The stent did not significantly reduce the signal-to-noise ratio. Trans-stent cavitation activity was also detected in vivo via passive cavitation imaging when echogenic liposomes were insonified by the 500-kHz transducer. When stable cavitation was detected, delivery of the fluorophore into the arterial wall was observed. Increased echogenicity within the stent was also observed when echogenic liposomes were administered. Thus, both B-mode ultrasound imaging and cavitation imaging are feasible in the presence of an endovascular stent in vivo. Demonstration of this capability supports future studies to monitor restenosis with contrast-enhanced ultrasound and pursue image-guided ultrasound-mediated drug delivery to inhibit restenosis. Copyright © 2016 World Federation for
Integrated ultrasound and gamma imaging probe for medical diagnosis

International Nuclear Information System (INIS)

Pani, R.; Pellegrini, R.; Cinti, M. N.; Polito, C.; Orlandi, C.; Fabbri, A.; Vincentis, G. De

2016-01-01

In the last few years, integrated multi-modality systems have been developed, aimed at improving the accuracy of medical diagnosis correlating information from different imaging techniques. In this contest, a novel dual modality probe is proposed, based on an ultrasound detector integrated with a small field of view single photon emission gamma camera. The probe, dedicated to visualize small organs or tissues located at short depths, performs dual modality images and permits to correlate morphological and functional information. The small field of view gamma camera consists of a continuous NaI:Tl scintillation crystal coupled with two multi-anode photomultiplier tubes. Both detectors were characterized in terms of position linearity and spatial resolution performances in order to guarantee the spatial correspondence between the ultrasound and the gamma images. Finally, dual-modality images of custom phantoms are obtained highlighting the good co-registration between ultrasound and gamma images, in terms of geometry and image processing, as a consequence of calibration procedures
Ultrasound and MR imaging of acute myositis

International Nuclear Information System (INIS)

Schedel, H.; Reimers, C.D.; Vogl, T.; Lissner, J.

1992-01-01

Ultrasound and MR imaging are both methods suitable for imaging neuromuscular diseases; however, contrast media like Gd-DTPA are, to our knowledge, not used so far. In this article we report about our experience of the use of Gd-DTPA in imaging myositis. (orig.)
In Vivo Real Time Volumetric Synthetic Aperture Ultrasound Imaging

DEFF Research Database (Denmark)

Bouzari, Hamed; Rasmussen, Morten Fischer; Brandt, Andreas Hjelm

2015-01-01

Synthetic aperture (SA) imaging can be used to achieve real-time volumetric ultrasound imaging using 2-D array transducers. The sensitivity of SA imaging is improved by maximizing the acoustic output, but one must consider the limitations of an ultrasound system, both technical and biological....... This paper investigates the in vivo applicability and sensitivity of volumetric SA imaging. Utilizing the transmit events to generate a set of virtual point sources, a frame rate of 25 Hz for a 90° x 90° field-of-view was achieved. Data were obtained using a 3.5 MHz 32 x 32 elements 2-D phased array...... transducer connected to the experimental scanner (SARUS). Proper scaling is applied to the excitation signal such that intensity levels are in compliance with the U.S. Food and Drug Administration regulations for in vivo ultrasound imaging. The measured Mechanical Index and spatial-peak- temporal...
Hybrid Photoacoustic/Ultrasound Tomograph for Real-Time Finger Imaging.

Science.gov (United States)

Oeri, Milan; Bost, Wolfgang; Sénégond, Nicolas; Tretbar, Steffen; Fournelle, Marc

2017-10-01

We report a target-enclosing, hybrid tomograph with a total of 768 elements based on capacitive micromachined ultrasound transducer technology and providing fast, high-resolution 2-D/3-D photoacoustic and ultrasound tomography tailored to finger imaging. A freely programmable ultrasound beamforming platform sampling data at 80 MHz was developed to realize plane wave transmission under multiple angles. A multiplexing unit enables the connection and control of a large number of elements. Fast image reconstruction is provided by GPU processing. The tomograph is composed of four independent and fully automated movable arc-shaped transducers, allowing imaging of all three finger joints. The system benefits from photoacoustics, yielding high optical contrast and enabling visualization of finger vascularization, and ultrasound provides morphologic information on joints and surrounding tissue. A diode-pumped, Q-switched Nd:YAG laser and an optical parametric oscillator are used to broaden the spectrum of emitted wavelengths to provide multispectral imaging. Custom-made optical fiber bundles enable illumination of the region of interest in the plane of acoustic detection. Precision in positioning of the probe in motion is ensured by use of a motor-driven guide slide. The current position of the probe is encoded by the stage and used to relate ultrasound and photoacoustic signals to the corresponding region of interest of the suspicious finger joint. The system is characterized in phantoms and a healthy human finger in vivo. The results obtained promise to provide new opportunities in finger diagnostics and establish photoacoustic/ultrasound-tomography in medical routine. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation.

Directory of Open Access Journals (Sweden)

Yi-Da Liu

Full Text Available Radiofrequency ablation (RFA has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15 were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.

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

Science.gov (United States)

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

2006-05-01

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
Speckle noise reduction in breast ultrasound images: SMU (srad median unsharp) approch

International Nuclear Information System (INIS)

Njeh, I.; Sassi, O. B.; Ben Hamida, A.; Chtourou, K.

2011-01-01

Image denoising has become a very essential for better information extraction from the image and mainly from so noised ones, such as ultrasound images. In certain cases, for instance in ultrasound images, the noise can restrain information which is valuable for the general practitioner. Consequently medical images are very inconsistent, and it is crucial to operate case to case. This paper presents a novel algorithm SMU (Srad Median Unsharp) for noise suppression in ultrasound breast images in order to realize a computer aided diagnosis (CAD) for breast cancer.
Comparison of daily megavoltage electronic portal imaging or kilovoltage imaging with marker seeds to ultrasound imaging or skin marks for prostate localization and treatment positioning in patients with prostate cancer

International Nuclear Information System (INIS)

Serago, Christopher F.; Buskirk, Steven J.; Igel, Todd C.; Gale, Ashley A.; Serago, Nicole E.; Earle, John D.

2006-01-01

Purpose: To compare the accuracy of imaging modalities, immobilization, localization, and positioning techniques in patients with prostate cancer. Methods and Materials: Thirty-five patients with prostate cancer had gold marker seeds implanted transrectally and were treated with fractionated radiotherapy. Twenty of the 35 patients had limited immobilization; the remaining had a vacuum-based immobilization. Patient positioning consisted of alignment with lasers to skin marks, ultrasound or kilovoltage X-ray imaging, optical guidance using infrared reflectors, and megavoltage electronic portal imaging (EPI). The variance of each positioning technique was compared to the patient position determined from the pretreatment EPI. Results: With limited immobilization, the average difference between the skin marks' laser position and EPI pretreatment position is 9.1 ± 5.3 mm, the average difference between the skin marks' infrared position and EPI pretreatment position is 11.8 ± 7.2 mm, the average difference between the ultrasound position and EPI pretreatment position is 7.0 ± 4.6 mm, the average difference between kV imaging and EPI pretreatment position is 3.5 ± 3.1 mm, and the average intrafraction movement during treatment is 3.4 ± 2.7 mm. For the patients with the vacuum-style immobilization, the average difference between the skin marks' laser position and EPI pretreatment position is 10.7 ± 4.6 mm, the average difference between kV imaging and EPI pretreatment position is 1.9 ± 1.5 mm, and the average intrafraction movement during treatment is 2.1 ± 1.5 mm. Conclusions: Compared with use of skin marks, ultrasound imaging for positioning provides an increased degree of agreement to EPI-based positioning, though not as favorable as kV imaging fiducial seeds. Intrafraction movement during treatment decreases with improved immobilization
Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... to evaluate the: appendix stomach/ pylorus liver gallbladder spleen pancreas intestines kidneys bladder testicles ovaries uterus Abdominal ultrasound images can be used to help diagnose appendicitis in children. Except for traumatic injury, appendicitis is the most common reason for emergency ...
Non-linear Ultrasound Imaging

DEFF Research Database (Denmark)

Du, Yigang

.3% relative to the measurement from a 1 inch diameter transducer. A preliminary study for harmonic imaging using synthetic aperture sequential beamforming (SASB) has been demonstrated. A wire phantom underwater measurement is made by an experimental synthetic aperture real-time ultrasound scanner (SARUS......) with a linear array transducer. The second harmonic imaging is obtained by a pulse inversion technique. The received data is beamformed by the SASB using a Beamformation Toolbox. In the measurements the lateral resolution at -6 dB is improved by 66% compared to the conventional imaging algorithm. There is also...... a 35% improvement for the lateral resolution at -6 dB compared with the sole harmonic imaging and a 46% improvement compared with merely using the SASB....
Electrical impedance tomography imaging using a priori ultrasound data

Directory of Open Access Journals (Sweden)

Soleimani Manuchehr

2006-02-01

Full Text Available Abstract Background Different imaging systems (e.g. electrical, magnetic, and ultrasound rely on a wide variety of physical properties, and the datasets obtained from such systems provide only partial information about the unknown true state. One approach is to choose complementary imaging systems, and to combine the information to achieve a better representation. Methods This paper discusses the combination of ultrasound and electrical impedance tomography (EIT information. Ultrasound reflection signals are good at locating sharp acoustic density changes associated with the boundaries of objects. Some boundaries, however, may be indeterminable due to masking from intermediate boundaries or because they are outside the ultrasound beam. Conversely, the EIT data contains relatively low-quality information, but it includes the whole region enclosed by the electrodes. Results Results are shown from a narrowband level-set method applied to 2D and 3D EIT incorporating limited angle ultrasound time of flight data. Conclusion The EIT reconstruction is shown to be faster and more accurate using the additional edge information from both one and four transducer ultrasound systems.
Learning to Diagnose Cirrhosis with Liver Capsule Guided Ultrasound Image Classification

Directory of Open Access Journals (Sweden)

Xiang Liu

2017-01-01

Full Text Available This paper proposes a computer-aided cirrhosis diagnosis system to diagnose cirrhosis based on ultrasound images. We first propose a method to extract a liver capsule on an ultrasound image, then, based on the extracted liver capsule, we fine-tune a deep convolutional neural network (CNN model to extract features from the image patches cropped around the liver capsules. Finally, a trained support vector machine (SVM classifier is applied to classify the sample into normal or abnormal cases. Experimental results show that the proposed method can effectively extract the liver capsules and accurately classify the ultrasound images.
Detecting breast microcalcifications using super-resolution and wave-equation ultrasound imaging: a numerical phantom study

Energy Technology Data Exchange (ETDEWEB)

Huang, Lianjie [Los Alamos National Laboratory; Simonetti, Francesco [IMPERIAL COLLEGE LONDON; Huthwaite, Peter [IMPERIAL COLLEGE LONDON; Rosenberg, Robert [UNM; Williamson, Michael [UNM

2010-01-01

Ultrasound image resolution and quality need to be significantly improved for breast microcalcification detection. Super-resolution imaging with the factorization method has recently been developed as a promising tool to break through the resolution limit of conventional imaging. In addition, wave-equation reflection imaging has become an effective method to reduce image speckles by properly handling ultrasound scattering/diffraction from breast heterogeneities during image reconstruction. We explore the capabilities of a novel super-resolution ultrasound imaging method and a wave-equation reflection imaging scheme for detecting breast microcalcifications. Super-resolution imaging uses the singular value decomposition and a factorization scheme to achieve an image resolution that is not possible for conventional ultrasound imaging. Wave-equation reflection imaging employs a solution to the acoustic-wave equation in heterogeneous media to backpropagate ultrasound scattering/diffraction waves to scatters and form images of heterogeneities. We construct numerical breast phantoms using in vivo breast images, and use a finite-difference wave-equation scheme to generate ultrasound data scattered from inclusions that mimic microcalcifications. We demonstrate that microcalcifications can be detected at full spatial resolution using the super-resolution ultrasound imaging and wave-equation reflection imaging methods.
Integrated ultrasound and magnetic resonance imaging for simultaneous temperature and cavitation monitoring during focused ultrasound therapies.

Science.gov (United States)

Arvanitis, Costas D; McDannold, Nathan

2013-11-01

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

Science.gov (United States)

Heales, Luke James; Broadhurst, Nathan; Mellor, Rebecca; Hodges, Paul William; Vicenzino, Bill

2014-11-01

Lateral epicondylalgia (LE) is clinically diagnosed as pain over the lateral elbow that is provoked by gripping. Usually, LE responds well to conservative intervention; however, those who fail such treatment require further evaluation, including musculoskeletal ultrasound. Previous studies of musculoskeletal ultrasound have methodological flaws, such as lack of assessor blinding and failure to control for participant age, sex, and arm dominance. The purpose of this study was to assess the diagnostic use of blinded ultrasound imaging in people with clinically diagnosed LE compared with that in a control group matched for age, sex, and arm dominance. Participants (30 with LE and 30 controls) underwent clinical examination as the criterion standard test. Unilateral LE was defined as pain over the lateral epicondyle, which was provoked by palpation, resisted wrist and finger extension, and gripping. Controls without symptoms were matched for age, sex, and arm dominance. Ultrasound investigations were performed by two sonographers using a standardized protocol. Grayscale images were assessed for signs of tendon pathology and rated on a four-point ordinal scale. Power Doppler was used to assess neovascularity and rated on a five-point ordinal scale. The combination of grayscale and power Doppler imaging revealed an overall sensitivity of 90% and specificity of 47%. The positive and negative likelihood ratios for combined grayscale and power Doppler imaging were 1.69 and 0.21, respectively. Although ultrasound imaging helps confirm the absence of LE, when findings are negative for tendinopathic changes, the high prevalence of tendinopathic changes in pain-free controls challenges the specificity of the measure. The validity of ultrasound imaging to confirm tendon pathology in clinically diagnosed LE requires further study with strong methodology.
Imaging of plantar fascia disorders: findings on plain radiography, ultrasound and magnetic resonance imaging.

Science.gov (United States)

Draghi, Ferdinando; Gitto, Salvatore; Bortolotto, Chandra; Draghi, Anna Guja; Ori Belometti, Gioia

2017-02-01

Plantar fascia (PF) disorders commonly cause heel pain and disability in the general population. Imaging is often required to confirm diagnosis. This review article aims to provide simple and systematic guidelines for imaging assessment of PF disease, focussing on key findings detectable on plain radiography, ultrasound and magnetic resonance imaging (MRI). Sonographic characteristics of plantar fasciitis include PF thickening, loss of fibrillar structure, perifascial collections, calcifications and hyperaemia on Doppler imaging. Thickening and signal changes in the PF as well as oedema of adjacent soft tissues and bone marrow can be assessed on MRI. Radiographic findings of plantar fasciitis include PF thickening, cortical irregularities and abnormalities in the fat pad located deep below the PF. Plantar fibromatosis appears as well-demarcated, nodular thickenings that are iso-hypoechoic on ultrasound and show low-signal intensity on MRI. PF tears present with partial or complete fibre interruption on both ultrasound and MRI. Imaging description of further PF disorders, including xanthoma, diabetic fascial disease, foreign-body reactions and plantar infections, is detailed in the main text. Ultrasound and MRI should be considered as first- and second-line modalities for assessment of PF disorders, respectively. Indirect findings of PF disease can be ruled out on plain radiography. Teaching Points • PF disorders commonly cause heel pain and disability in the general population.• Imaging is often required to confirm diagnosis or reveal concomitant injuries.• Ultrasound and MRI respectively represent the first- and second-line modalities for diagnosis.• Indirect findings of PF disease can be ruled out on plain radiography.
Characterization of controlled bone defects using 2D and 3D ultrasound imaging techniques

Energy Technology Data Exchange (ETDEWEB)

Parmar, Biren J; Longsine, Whitney; Han, Arum; Righetti, Raffaella [Department of Electrical and Computer Engineering, Dwight Look College of Engineering, Texas A and M University, College Station, TX (United States); Sabonghy, Eric P [OneOrtho Orthopedic Surgery Clinic, Houston, TX (United States); Tasciotti, Ennio; Ferrari, Mauro [Department of Nanomedicine and Biomedical Engineering, University of Texas Health Science Center at Houston, Houston, TX (United States); Weiner, Bradley K, E-mail: righetti@ece.tamu.ed [Division of Spinal Surgery, Department of Orthopaedic Surgery, Methodist Hospital, Houston, TX 77030 (United States)

2010-08-21

Ultrasound is emerging as an attractive alternative modality to standard x-ray and CT methods for bone assessment applications. As of today, however, there is a lack of systematic studies that investigate the performance of diagnostic ultrasound techniques in bone imaging applications. This study aims at understanding the performance limitations of new ultrasound techniques for imaging bones in controlled experiments in vitro. Experiments are performed on samples of mammalian and non-mammalian bones with controlled defects with size ranging from 400 {mu}m to 5 mm. Ultrasound findings are statistically compared with those obtained from the same samples using standard x-ray imaging modalities and optical microscopy. The results of this study demonstrate that it is feasible to use diagnostic ultrasound imaging techniques to assess sub-millimeter bone defects in real time and with high accuracy and precision. These results also demonstrate that ultrasound imaging techniques perform comparably better than x-ray imaging and optical imaging methods, in the assessment of a wide range of controlled defects both in mammalian and non-mammalian bones. In the future, ultrasound imaging techniques might provide a cost-effective, real-time, safe and portable diagnostic tool for bone imaging applications.
Characterization of ultrasound elevation beamwidth artifacts for prostate brachytherapy needle insertion

International Nuclear Information System (INIS)

Peikari, Mohammad; Chen, Thomas Kuriran; Lasso, Anras; Heffter, Tamas; Fichtinger, Gabor; Burdette, Everette C.

2012-01-01

Purpose: Ultrasound elevation beamwidth leads to image artifacts and uncertainties in localizing objects (such as a surgical needle) in ultrasound images. The authors examined the clinical significance of errors caused by elevation beamwidth artifacts and imaging parameters in needle insertion procedures. Methods: Beveled prostate brachytherapy needles were inserted through all holes of a grid template under real-time transrectal ultrasound (TRUS) guidance. The needle tip position as indicated by the TRUS image was compared to their observed physical location. A new device was developed to measure the ultrasound elevation beamwidth. Results: Imaging parameters of the TRUS scanner have direct impact on the localization error ranging from 0.5 up to 4 mm. The smallest localization error was observed laterally close to the center of the grid template and axially within the beam's focal zone. Largest localization error occurs laterally around both sides of the grid template and axially within the beam's far field. The authors also found that the localization errors vary with both lateral and elevation offsets. Conclusions: The authors found properly adjusting the TRUS imaging settings to lower the ultrasound gain and power effectively minimized the appearance of elevation beamwidth artifacts and in turn reduced the localization errors of the needle tip.
Evaluation of Image-Guidance Strategies in the Treatment of Localized Prostate Cancer

International Nuclear Information System (INIS)

Kupelian, Patrick A.; Lee, Choonik; Langen, Katja M.; Zeidan, Omar A.; Manon, Rafael R.; Willoughby, Twyla R.; Meeks, Sanford L.

2008-01-01

Purpose: To compare different image-guidance strategies in the alignment of prostate cancer patients. Using data from patients treated using daily image guidance, the remaining setup errors for several different strategies were retrospectively calculated. Methods and Materials: The alignment data from 74 patients treated with helical tomotherapy were analyzed, resulting in a data set of 2,252 fractions during which a megavoltage computed tomography image was used for image guidance with intraprostatic metallic fiducials. Given the daily positional adjustments, a variety of protocols, differing in imaging frequency and method, were retrospectively studied. The residual setup errors were determined for each protocol. Results: As expected, the systematic errors were effectively reduced with imaging. However, the random errors were unaffected. Even when image guidance was performed every other day with a running mean of the previous displacements, residual setup errors >5 mm occurred in 24% of all fractions. This frequency increased to about 40% if setup errors >3 mm were scored. Conclusion: Setup errors increased with decreasing frequency of image guidance. However, residual errors were still significant at the 5-mm level, even with imaging was performed every other day. This suggests that localizations must be performed daily in the set up of prostate cancer patients during a course of external beam radiotherapy
A single FPGA-based portable ultrasound imaging system for point-of-care applications.

Science.gov (United States)

Kim, Gi-Duck; Yoon, Changhan; Kye, Sang-Bum; Lee, Youngbae; Kang, Jeeun; Yoo, Yangmo; Song, Tai-kyong

2012-07-01

We present a cost-effective portable ultrasound system based on a single field-programmable gate array (FPGA) for point-of-care applications. In the portable ultrasound system developed, all the ultrasound signal and image processing modules, including an effective 32-channel receive beamformer with pseudo-dynamic focusing, are embedded in an FPGA chip. For overall system control, a mobile processor running Linux at 667 MHz is used. The scan-converted ultrasound image data from the FPGA are directly transferred to the system controller via external direct memory access without a video processing unit. The potable ultrasound system developed can provide real-time B-mode imaging with a maximum frame rate of 30, and it has a battery life of approximately 1.5 h. These results indicate that the single FPGA-based portable ultrasound system developed is able to meet the processing requirements in medical ultrasound imaging while providing improved flexibility for adapting to emerging POC applications.
Ultrasound imaging in urogynecology – state of the art 2016

Directory of Open Access Journals (Sweden)

Michał Bogusiewicz

2016-11-01

Full Text Available The role of ultrasound imaging in urogynecology is not clearly defined. Despite significant developments in visualization techniques and interpretation of images, pelvic ultrasound is still more a tool for research than for clinical practice. Structures of the lower genitourinary tract and pelvic floor can be visualized from different approaches: transperineal, introital, transvaginal, abdominal or endoanal. According to contemporary guidelines and recommendations, the role of ultrasound in urogynecology is limited to the measurement of post-void residue. However, in many instances, including planning and audit of surgical procedures, management of recurrences or complications, ultrasound may be proposed as the initial examination of choice. Ultrasound may be used for assessment of bladder neck mobility before anti-incontinence procedures. On rare occasions it is helpful in recognition of pathologies mimicking vaginal prolapse such as vaginal cyst, urethral diverticula or rectal intussusception. In patients subjected to suburethral slings, causes of surgery failure or postsurgical voiding dysfunctions can be revealed by imaging. Many reports link the location of a tape close to the bladder neck to unfavorable outcomes of sling surgery. Some postoperative complications, such as urinary retention, mesh malposition, hematoma, or urinary tract injury, can be diagnosed by ultrasound. On the other hand, the clinical value of some applications of ultrasound in urogynecology, for example measurement of the bladder wall thickness as a marker of detrusor overactivity, has not been proved.
Ultrasound guidance versus anatomical landmarks for internal jugular vein catheterization.

Science.gov (United States)

Brass, Patrick; Hellmich, Martin; Kolodziej, Laurentius; Schick, Guido; Smith, Andrew F

2015-01-09

Central venous catheters (CVCs) can help with diagnosis and treatment of the critically ill. The catheter may be placed in a large vein in the neck (internal jugular vein), upper chest (subclavian vein) or groin (femoral vein). Whilst this is beneficial overall, inserting the catheter risks arterial puncture and other complications and should be performed with as few attempts as possible. Traditionally, anatomical 'landmarks' on the body surface were used to find the correct place in which to insert catheters, but ultrasound imaging is now available. A Doppler mode is sometimes used to supplement plain 'two-dimensional' ultrasound. The primary objective of this review was to evaluate the effectiveness and safety of two-dimensional (imaging ultrasound (US) or ultrasound Doppler (USD)) guided puncture techniques for insertion of central venous catheters via the internal jugular vein in adults and children. We assessed whether there was a difference in complication rates between traditional landmark-guided and any ultrasound-guided central vein puncture.Our secondary objectives were to assess whether the effect differs between US and USD; whether the effect differs between ultrasound used throughout the puncture ('direct') and ultrasound used only to identify and mark the vein before the start of the puncture procedure (indirect'); and whether the effect differs between different groups of patients or between different levels of experience among those inserting the catheters. We searched the Central Register of Controlled Trials (CENTRAL) (2013, Issue 1), MEDLINE (1966 to 15 January 2013), EMBASE (1966 to 15 January 2013), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to 15 January 2013 ), reference lists of articles, 'grey literature' and dissertations. An additional handsearch focused on intensive care and anaesthesia journals and abstracts and proceedings of scientific meetings. We attempted to identify unpublished or ongoing studies
Technical tips to perform safe and effective ultrasound guided steroid joint injections in children.

Science.gov (United States)

Parra, Dimitri A

2015-01-01

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

Science.gov (United States)

Hua, Jeremy; Chen, Ssu-Kuang; Kim, Yongmin

2009-01-01

Dental erosion has been growing increasingly prevalent with the rise in consumption of heavy starches, sugars, coffee, and acidic beverages. In addition, various disorders, such as Gastroenterological Reflux Disease (GERD), have symptoms of rapid rates of tooth erosion. The measurement of enamel thickness would be important for dentists to assess the progression of enamel loss from all forms of erosion, attrition, and abrasion. Characterizing enamel loss is currently done with various subjective indexes that can be interpreted in different ways by different dentists. Ultrasound has been utilized since the 1960s to determine internal tooth structure, but with mixed results. Via image processing and enhancement, we were able to refine B-mode dental ultrasound images for more accurate enamel thickness measurements. The mean difference between the measured thickness of the occlusal enamel from ultrasound images and corresponding gold standard CT images improved from 0.55 mm to 0.32 mm with image processing (p = 0.033). The difference also improved from 0.62 to 0.53 mm at the buccal/lingual enamel surfaces, but not significantly (p = 0.38).
Deconvolution of ultrasound images

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt

1992-01-01

Based on physical models, it is indicated that the received pressure field in ultrasound B-mode images can be described by a convolution between a tissue reflection signal and the emitted pressure field. This result is used in a description of current image formation and in formulating a new...... processing scheme. The suggested estimator can take into account the dispersive attenuation, the temporal and spatial variation of the pulse, and the change in reflection strength and signal-to-noise ratio. Details of the algorithm and the estimation of parameters to be used are given. The performance...

Children's (Pediatric) Abdominal Ultrasound Imaging

Medline Plus

Full Text Available ... an area of tenderness, your child may feel pressure or minor pain from the procedure. If a Doppler ultrasound study is performed, your child may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured. Once the imaging ...
A multimodal imaging framework for enhanced robot-assisted partial nephrectomy guidance

Science.gov (United States)

Halter, Ryan J.; Wu, Xiaotian; Hartov, Alex; Seigne, John; Khan, Shadab

2015-03-01

Robot-assisted laparoscopic partial nephrectomies (RALPN) are performed to treat patients with locally confined renal carcinoma. There are well-documented benefits to performing partial (opposed to radical) kidney resections and to using robot-assisted laparoscopic (opposed to open) approaches. However, there are challenges in identifying tumor margins and critical benign structures including blood vessels and collecting systems during current RALPN procedures. The primary objective of this effort is to couple multiple image and data streams together to augment visual information currently provided to surgeons performing RALPN and ultimately ensure complete tumor resection and minimal damage to functional structures (i.e. renal vasculature and collecting systems). To meet this challenge we have developed a framework and performed initial feasibility experiments to couple pre-operative high-resolution anatomic images with intraoperative MRI, ultrasound (US) and optical-based surface mapping and kidney tracking. With these registered images and data streams, we aim to overlay the high-resolution contrast-enhanced anatomic (CT or MR) images onto the surgeon's view screen for enhanced guidance. To date we have integrated the following components of our framework: 1) a method for tracking an intraoperative US probe to extract the kidney surface and a set of embedded kidney markers, 2) a method for co-registering intraoperative US scans with pre-operative MR scans, and 3) a method for deforming pre-op scans to match intraoperative scans. These components have been evaluated through phantom studies to demonstrate protocol feasibility.
Molecular Ultrasound Imaging for the Detection of Neural Inflammation

Science.gov (United States)

Volz, Kevin R.

Molecular imaging is a form of nanotechnology that enables the noninvasive examination of biological processes in vivo. Radiopharmaceutical agents are used to selectively target biochemical markers, which permits their detection and evaluation. Early visualization of molecular variations indicative of pathophysiological processes can aid in patient diagnoses and management decisions. Molecular imaging is performed by introducing molecular probes into the body. Molecular probes are often contrast agents that have been nanoengineered to selectively target and tether to molecules, enabling their radiologic identification. Ultrasound contrast agents have been demonstrated as an effective method of detecting perfusion at the tissue level. Through a nanoengineering process, ultrasound contrast agents can be targeted to specific molecules, thereby extending ultrasound's capabilities from the tissue to molecular level. Molecular ultrasound, or targeted contrast enhanced ultrasound (TCEUS), has recently emerged as a popular molecular imaging technique due to its ability to provide real-time anatomical and functional information in the absence of ionizing radiation. However, molecular ultrasound represents a novel form of molecular imaging, and consequently remains largely preclinical. A review of the TCEUS literature revealed multiple preclinical studies demonstrating its success in detecting inflammation in a variety of tissues. Although, a gap was identified in the existing evidence, as TCEUS effectiveness for detection of neural inflammation in the spinal cord was unable to be uncovered. This gap in knowledge, coupled with the profound impacts that this TCEUS application could have clinically, provided rationale for its exploration, and use as contributory evidence for the molecular ultrasound body of literature. An animal model that underwent a contusive spinal cord injury was used to establish preclinical evidence of TCEUS to detect neural inflammation. Imaging was
Delay and Standard Deviation Beamforming to Enhance Specular Reflections in Ultrasound Imaging.

Science.gov (United States)

Bandaru, Raja Sekhar; Sornes, Anders Rasmus; Hermans, Jeroen; Samset, Eigil; D'hooge, Jan

2016-12-01

Although interventional devices, such as needles, guide wires, and catheters, are best visualized by X-ray, real-time volumetric echography could offer an attractive alternative as it avoids ionizing radiation; it provides good soft tissue contrast, and it is mobile and relatively cheap. Unfortunately, as echography is traditionally used to image soft tissue and blood flow, the appearance of interventional devices in conventional ultrasound images remains relatively poor, which is a major obstacle toward ultrasound-guided interventions. The objective of this paper was therefore to enhance the appearance of interventional devices in ultrasound images. Thereto, a modified ultrasound beamforming process using conventional-focused transmit beams is proposed that exploits the properties of received signals containing specular reflections (as arising from these devices). This new beamforming approach referred to as delay and standard deviation beamforming (DASD) was quantitatively tested using simulated as well as experimental data using a linear array transducer. Furthermore, the influence of different imaging settings (i.e., transmit focus, imaging depth, and scan angle) on the obtained image contrast was evaluated. The study showed that the image contrast of specular regions improved by 5-30 dB using DASD beamforming compared with traditional delay and sum (DAS) beamforming. The highest gain in contrast was observed when the interventional device was tilted away from being orthogonal to the transmit beam, which is a major limitation in standard DAS imaging. As such, the proposed beamforming methodology can offer an improved visualization of interventional devices in the ultrasound image with potential implications for ultrasound-guided interventions.
Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

International Nuclear Information System (INIS)

Tilli, Maddalena T; Parrish, Angela R; Cotarla, Ion; Jones, Laundette P; Johnson, Michael D; Furth, Priscilla A

2008-01-01

Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary
Power cavitation-guided blood-brain barrier opening with focused ultrasound and microbubbles

Science.gov (United States)

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

2018-03-01

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

International Nuclear Information System (INIS)

Amies, Christopher J.

2008-01-01

Over the last 30 years major improvements in medical imaging have played a significant role to help advance the management of oncology diseases. These advances have covered the continuum of care from screening, diagnosis, staging, treatment planning and intervention. More recently image guided radiation therapy (IGRT) has placed sophisticated imaging closer to the treatment event. The opportunity to improve care seems obvious; however the clinical benefits of IGRT are at present not easily proven and yet contribute to the complexity of treatment and the rising costs of care. It is proposed that this is in part due to the present immaturity of IGRT technology development, which is predominantly determined by the challenge of achieving precise delivery of radiation in one or many episodes (fractions) for very different diseases. There is no single type or mode of imaging that will be suitable to address all radiotherapy guidance challenges whether defined by the general criteria identified for a specific disease or the unique characteristics encountered with an individual patient. Finally the wide adoption of this or any medical technology general requires the attainment of a sufficient degree of safety and efficiency. I present the challenges faced by industry as well as select interesting technology based solutions and concepts that may help advance the field of oncology guidance
Molecular imaging with targeted contrast ultrasound.

Science.gov (United States)

Piedra, Mark; Allroggen, Achim; Lindner, Jonathan R

2009-01-01

Molecular imaging with contrast-enhanced ultrasound uses targeted microbubbles that are retained in diseased tissue. The resonant properties of these microbubbles produce acoustic signals in an ultrasound field. The microbubbles are targeted to diseased tissue by using certain chemical constituents in the microbubble shell or by attaching disease-specific ligands such as antibodies to the microbubble. In this review, we discuss the applications of this technique to pathological states in the cerebrovascular system including atherosclerosis, tumor angiogenesis, ischemia, intravascular thrombus, and inflammation. Copyright 2009 S. Karger AG, Basel.
Recursive ultrasound imaging

DEFF Research Database (Denmark)

2000-01-01

A method and an apparatus for recursive ultrasound imaging is presented. The method uses a Synthetic Transmit Aperture, but unlike previous approaches a new frame is created at every pulse emission. In receive, parallel beam forming is implemented. The beam formed RF data is added to the previously...... created RF lines. To keep the level of the signal, the RF data obtained previously, when emitting with the same element is subtracted from the RF lines. Up to 5000 frames/sec can be achieved for a tissue depth of 15 cm with a speed of sound of c = 1540 m/s. The high frame rate makes continuous imaging...... data possible, which can significantly enhance flow imaging. A point spread function 2° wide at -6 dB and grating lobes of $m(F) -50 dB is obtained with a 64 elements phased array with a central frequency ƒ¿0? = 3 MHz using a sparse transmit aperture using only 10 elements (N¿xmt? = 10) during pulse...
Segmentation of breast ultrasound images based on active contours using neutrosophic theory.

Science.gov (United States)

Lotfollahi, Mahsa; Gity, Masoumeh; Ye, Jing Yong; Mahlooji Far, A

2018-04-01

Ultrasound imaging is an effective approach for diagnosing breast cancer, but it is highly operator-dependent. Recent advances in computer-aided diagnosis have suggested that it can assist physicians in diagnosis. Definition of the region of interest before computer analysis is still needed. Since manual outlining of the tumor contour is tedious and time-consuming for a physician, developing an automatic segmentation method is important for clinical application. The present paper represents a novel method to segment breast ultrasound images. It utilizes a combination of region-based active contour and neutrosophic theory to overcome the natural properties of ultrasound images including speckle noise and tissue-related textures. First, due to inherent speckle noise and low contrast of these images, we have utilized a non-local means filter and fuzzy logic method for denoising and image enhancement, respectively. This paper presents an improved weighted region-scalable active contour to segment breast ultrasound images using a new feature derived from neutrosophic theory. This method has been applied to 36 breast ultrasound images. It generates true-positive and false-positive results, and similarity of 95%, 6%, and 90%, respectively. The purposed method indicates clear advantages over other conventional methods of active contour segmentation, i.e., region-scalable fitting energy and weighted region-scalable fitting energy.
Gynecologic radiation therapy. Novel approaches to image-guidance and management

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, Akila N. [Harvard Medical School, Boston, MA (United States). Dept. of Radiation Oncology; Kirisits, Christian; Poetter, Richard (eds.) [Vienna General Hospital Medical Univ. (Austria). Dept. of Radiotherapy; Erickson, Beth E. [Medical College of Wisconsin Clinics Froedtert Hospital, Milwaukee, WI (United States). Dept. of Radiation Oncology

2011-07-01

Recent advances in the treatment of gynecologic malignancies led to a new worldwide consensus to introduce image guidance to gynecologic radiation therapy, particularly to brachytherapy. The book summarizes the changed practice of management: treatment planning for cervical cancer, not modified for over 60 years, has been shifted to an image-based approach, endometrial cancer management with an increase in the use of chemotherapy and vaginal brachytherapy, and vaginal cancer therapy including image guidance and high-dose delivery with IMRT. (orig.)
Ultrasound-guided image fusion with computed tomography and magnetic resonance imaging. Clinical utility for imaging and interventional diagnostics of hepatic lesions

International Nuclear Information System (INIS)

Clevert, D.A.; Helck, A.; Paprottka, P.M.; Trumm, C.; Reiser, M.F.; Zengel, P.

2012-01-01

Abdominal ultrasound is often the first-line imaging modality for assessing focal liver lesions. Due to various new ultrasound techniques, such as image fusion, global positioning system (GPS) tracking and needle tracking guided biopsy, abdominal ultrasound now has great potential regarding detection, characterization and treatment of focal liver lesions. Furthermore, these new techniques will help to improve the clinical management of patients before and during interventional procedures. This article presents the principle and clinical impact of recently developed techniques in the field of ultrasound, e.g. image fusion, GPS tracking and needle tracking guided biopsy and discusses the results based on a feasibility study on 20 patients with focal hepatic lesions. (orig.) [de
Evolution of contrast agents for ultrasound imaging and ultrasound-mediated drug delivery

Directory of Open Access Journals (Sweden)

Vera ePaefgen

2015-09-01

Full Text Available Ultrasound is one of the most frequently used diagnostic methods. It is a non-invasive, comparably inexpensive imaging method with a broad spectrum of applications, which can be increased even more by using bubbles as contrast agents. There are various different types of bubbles: filled with different gases, composed of soft- or hard-shell materials, and ranging in size from nano- to micrometers. These intravascular contrast agents enable functional analyses, e.g. to acquire organ perfusion in real-time. Molecular analyses are achieved by coupling specific ligands to the bubbles’ shell, which bind to marker molecules in the area of interest. Bubbles can also be loaded with or attached to drugs, peptides or genes and can be destroyed by ultrasound pulses to locally release the entrapped agent. Recent studies show that ultrasound contrast agents are also valuable tools in hyperthermia-induced ablation therapy of tumors, or can increase cellular uptake of locally released drugs by enhancing membrane permeability. This review summarizes important steps in the development of ultrasound contrast agents and introduces the current clinical applications of contrast-enhanced ultrasound. Additionally, an overview of the recent developments in ultrasound probe design for functional and molecular diagnosis as well as for drug delivery is given.
Image guidance in trans-sphenoidal surgery for giant pituitary adenomas: Luxury or necessity?

Directory of Open Access Journals (Sweden)

Deepak Agrawal

2012-01-01

Full Text Available Background: In spite of availability of image guidance (neuronavigation at major centers around the world, most trans-sphenoidal surgeries for pituitary adenomas continue to be done under fluoroscopic control. On the other hand, the high mortality and morbidity for giant pituitary adenomas is mainly due to inadequate tumor removal. Aims and Objectives: The objective of this study was to study to utility of image guidance in trans-sphenoidal surgeries for optimizing tumor removal in giant pituitary adenomas. Materials and Methods: This was a prospective study carried out over a two years (January 2009-December 2010 in the Department of Neurosurgery, All India Institute of Medical Sciences. Patients with giant pituitary adenomas who underwent trans-sphenoidal surgery by the author were included. All surgeries were done under image-guidance only and no fluoroscopy was employed. Trajectory was defined using the image guidance and bone work done accordingly to optimize tumor removal. All patients had a contrast CT of the head done within 48 h of surgery to see for residual tumor. Observations and Results: Sixteen patients with pituitary adenomas were operated using only image-guidance in the study period. Twelve patients had virgin tumors and four patients had recurrent/residual tumors. In four patients, noncontrast MR images were used in for image guidance and contrast CT images were used in the rest. The mean set up time for image-guidance was 11 min (range 7-15 min. The mean ′′overall accuracy of registration′′ was 1.6 mm (range 1.4-2.1 mm. The mean operating time was 72 min (range 52-96 min. In all cases, midline and the relation of the carotid artery to the sella could be confirmed using the image-guidance. There were no intraoperative complications. Postoperative scans showed residual tumor in nine patients. The residual tumor was 25% in one patient (with a fibrous recurrent/residual tumor. Conclusions: Image guidance markedly improves
General Ultrasound Imaging

Medline Plus

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

Medline Plus

Full Text Available ... of an ultrasound examination. Doppler ultrasound , also called color Doppler ultrasonography, is a special ultrasound technique that ... kidneys. There are three types of Doppler ultrasound: Color Doppler uses a computer to convert Doppler measurements ...
GPU-Based Simulation of Ultrasound Imaging Artifacts for Cryosurgery Training

Science.gov (United States)

Keelan, Robert; Shimada, Kenji

2016-01-01

This study presents an efficient computational technique for the simulation of ultrasound imaging artifacts associated with cryosurgery based on nonlinear ray tracing. This study is part of an ongoing effort to develop computerized training tools for cryosurgery, with prostate cryosurgery as a development model. The capability of performing virtual cryosurgical procedures on a variety of test cases is essential for effective surgical training. Simulated ultrasound imaging artifacts include reverberation and reflection of the cryoprobes in the unfrozen tissue, reflections caused by the freezing front, shadowing caused by the frozen region, and tissue property changes in repeated freeze–thaw cycles procedures. The simulated artifacts appear to preserve the key features observed in a clinical setting. This study displays an example of how training may benefit from toggling between the undisturbed ultrasound image, the simulated temperature field, the simulated imaging artifacts, and an augmented hybrid presentation of the temperature field superimposed on the ultrasound image. The proposed method is demonstrated on a graphic processing unit at 100 frames per second, on a mid-range personal workstation, at two orders of magnitude faster than a typical cryoprocedure. This performance is based on computation with C++ accelerated massive parallelism and its interoperability with the DirectX-rendering application programming interface. PMID:26818026
On the reproducibility of expert-operated and robotic ultrasound acquisitions.

Science.gov (United States)

Kojcev, Risto; Khakzar, Ashkan; Fuerst, Bernhard; Zettinig, Oliver; Fahkry, Carole; DeJong, Robert; Richmon, Jeremy; Taylor, Russell; Sinibaldi, Edoardo; Navab, Nassir

2017-06-01

We present the evaluation of the reproducibility of measurements performed using robotic ultrasound imaging in comparison with expert-operated sonography. Robotic imaging for interventional procedures may be a valuable contribution, but requires reproducibility for its acceptance in clinical routine. We study this by comparing repeated measurements based on robotic and expert-operated ultrasound imaging. Robotic ultrasound acquisition is performed in three steps under user guidance: First, the patient is observed using a 3D camera on the robot end effector, and the user selects the region of interest. This allows for automatic planning of the robot trajectory. Next, the robot executes a sweeping motion following the planned trajectory, during which the ultrasound images and tracking data are recorded. As the robot is compliant, deviations from the path are possible, for instance due to patient motion. Finally, the ultrasound slices are compounded to create a volume. Repeated acquisitions can be performed automatically by comparing the previous and current patient surface. After repeated image acquisitions, the measurements based on acquisitions performed by the robotic system and expert are compared. Within our case series, the expert measured the anterior-posterior, longitudinal, transversal lengths of both of the left and right thyroid lobes on each of the 4 healthy volunteers 3 times, providing 72 measurements. Subsequently, the same procedure was performed using the robotic system resulting in a cumulative total of 144 clinically relevant measurements. Our results clearly indicated that robotic ultrasound enables more repeatable measurements. A robotic ultrasound platform leads to more reproducible data, which is of crucial importance for planning and executing interventions.
Photo-Acoustic Ultrasound Imaging to Distinguish Benign from Malignant Prostate Cancer

Science.gov (United States)

2016-09-01

tissue phantoms and animal models of disease . 15. SUBJECT TERMS Photoacoustic, Ultrasound imaging, transurethral probe 16. SECURITY CLASSIFICATION...visible, ultrasound images are unable to discriminate between benign or malignant cancers. In photoacoustic imaging, laser energy is transmitted ...40 g/L concentration of sea plaque agarose into DI water heated to approximately 80°C. A 10 g/L concentration of silica powder was then added to
Texture Based Quality Analysis of Simulated Synthetic Ultrasound Images Using Local Binary Patterns †

Directory of Open Access Journals (Sweden)

Prerna Singh

2017-12-01

Full Text Available Speckle noise reduction is an important area of research in the field of ultrasound image processing. Several algorithms for speckle noise characterization and analysis have been recently proposed in the area. Synthetic ultrasound images can play a key role in noise evaluation methods as they can be used to generate a variety of speckle noise models under different interpolation and sampling schemes, and can also provide valuable ground truth data for estimating the accuracy of the chosen methods. However, not much work has been done in the area of modeling synthetic ultrasound images, and in simulating speckle noise generation to get images that are as close as possible to real ultrasound images. An important aspect of simulated synthetic ultrasound images is the requirement for extensive quality assessment for ensuring that they have the texture characteristics and gray-tone features of real images. This paper presents texture feature analysis of synthetic ultrasound images using local binary patterns (LBP and demonstrates the usefulness of a set of LBP features for image quality assessment. Experimental results presented in the paper clearly show how these features could provide an accurate quality metric that correlates very well with subjective evaluations performed by clinical experts.

Ultrafast ultrasound localization microscopy for deep super-resolution vascular imaging

Science.gov (United States)

Errico, Claudia; Pierre, Juliette; Pezet, Sophie; Desailly, Yann; Lenkei, Zsolt; Couture, Olivier; Tanter, Mickael

2015-11-01

Non-invasive imaging deep into organs at microscopic scales remains an open quest in biomedical imaging. Although optical microscopy is still limited to surface imaging owing to optical wave diffusion and fast decorrelation in tissue, revolutionary approaches such as fluorescence photo-activated localization microscopy led to a striking increase in resolution by more than an order of magnitude in the last decade. In contrast with optics, ultrasonic waves propagate deep into organs without losing their coherence and are much less affected by in vivo decorrelation processes. However, their resolution is impeded by the fundamental limits of diffraction, which impose a long-standing trade-off between resolution and penetration. This limits clinical and preclinical ultrasound imaging to a sub-millimetre scale. Here we demonstrate in vivo that ultrasound imaging at ultrafast frame rates (more than 500 frames per second) provides an analogue to optical localization microscopy by capturing the transient signal decorrelation of contrast agents—inert gas microbubbles. Ultrafast ultrasound localization microscopy allowed both non-invasive sub-wavelength structural imaging and haemodynamic quantification of rodent cerebral microvessels (less than ten micrometres in diameter) more than ten millimetres below the tissue surface, leading to transcranial whole-brain imaging within short acquisition times (tens of seconds). After intravenous injection, single echoes from individual microbubbles were detected through ultrafast imaging. Their localization, not limited by diffraction, was accumulated over 75,000 images, yielding 1,000,000 events per coronal plane and statistically independent pixels of ten micrometres in size. Precise temporal tracking of microbubble positions allowed us to extract accurately in-plane velocities of the blood flow with a large dynamic range (from one millimetre per second to several centimetres per second). These results pave the way for deep non
Non-Invasive In Vivo Ultrasound Temperature Estimation

Science.gov (United States)

Bayat, Mahdi

New emerging technologies in thermal therapy require precise monitoring and control of the delivered thermal dose in a variety of situations. The therapeutic temperature changes in target tissues range from few degrees for releasing chemotherapy drugs encapsulated in the thermosensitive liposomes to boiling temperatures in complete ablation of tumors via cell necrosis. High intensity focused ultrasound (HIFU) has emerged as a promising modality for noninvasive surgery due to its ability to create precise mechanical and thermal effects at the target without affecting surrounding tissues. An essential element in all these procedures, however, is accurate estimation of the target tissue temperature during the procedure to ensure its safety and efficacy. The advent of diagnostic imaging tools for guidance of thermal therapy was a key factor in the clinical acceptance of these minimally invasive or noninvasive methods. More recently, ultrasound and magnetic resonance (MR) thermography techniques have been proposed for guidance, monitoring, and control of noninvasive thermal therapies. MR thermography has shown acceptable sensitivity and accuracy in imaging temperature change and it is currently FDA-approved on clinical HIFU units. However, it suffers from limitations like cost of integration with ultrasound therapy system and slow rate of imaging for real time guidance. Ultrasound, on the other hand, has the advantage of real time imaging and ease of integration with the therapy system. An infinitesimal model for imaging temperature change using pulse-echo ultrasound has been demonstrated, including in vivo small-animal imaging. However, this model suffers from limitations that prevent demonstration in more clinically-relevant settings. One limitation stems from the infinitesimal nature of the model, which results in spatial inconsistencies of the estimated temperature field. Another limitation is the sensitivity to tissue motion and deformation during in vivo, which
Space imaging infrared optical guidance for autonomous ground vehicle

Science.gov (United States)

Akiyama, Akira; Kobayashi, Nobuaki; Mutoh, Eiichiro; Kumagai, Hideo; Yamada, Hirofumi; Ishii, Hiromitsu

2008-08-01

We have developed the Space Imaging Infrared Optical Guidance for Autonomous Ground Vehicle based on the uncooled infrared camera and focusing technique to detect the objects to be evaded and to set the drive path. For this purpose we made servomotor drive system to control the focus function of the infrared camera lens. To determine the best focus position we use the auto focus image processing of Daubechies wavelet transform technique with 4 terms. From the determined best focus position we transformed it to the distance of the object. We made the aluminum frame ground vehicle to mount the auto focus infrared unit. Its size is 900mm long and 800mm wide. This vehicle mounted Ackerman front steering system and the rear motor drive system. To confirm the guidance ability of the Space Imaging Infrared Optical Guidance for Autonomous Ground Vehicle we had the experiments for the detection ability of the infrared auto focus unit to the actual car on the road and the roadside wall. As a result the auto focus image processing based on the Daubechies wavelet transform technique detects the best focus image clearly and give the depth of the object from the infrared camera unit.
Effects of line fiducial parameters and beamforming on ultrasound calibration

OpenAIRE

Ameri, Golafsoun; Baxter, John S. H.; McLeod, A. Jonathan; Peters, Terry M.; Chen, Elvis C. S.

2017-01-01

Ultrasound (US)-guided interventions are often enhanced via integration with an augmented reality environment, a necessary component of which is US calibration. Calibration requires the segmentation of fiducials, i.e., a phantom, in US images. Fiducial localization error (FLE) can decrease US calibration accuracy, which fundamentally affects the total accuracy of the interventional guidance system. Here, we investigate the effects of US image reconstruction techniques as well as phantom mater...
TU-A-201-00: Image Guidance Technologies and Management Strategies

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-06-15

Recent years have seen a widespread proliferation of available in-room image guidance systems for radiation therapy target localization with many centers having multiple in-room options. In this session, available imaging systems for in-room IGRT will be reviewed highlighting the main differences in workflow efficiency, targeting accuracy and image quality as it relates to target visualization. Decision-making strategies for integrating these tools into clinical image guidance protocols that are tailored to specific disease sites like H&N, lung, pelvis, and spine SBRT will be discussed. Learning Objectives: Major system characteristics of a wide range of available in-room imaging systems for IGRT. Advantages / disadvantages of different systems for site-specific IGRT considerations. Concepts of targeting accuracy and time efficiency in designing clinical imaging protocols.
Development of ultrasound-assisted fluorescence imaging of indocyanine green.

Science.gov (United States)

Morikawa, Hiroyasu; Toyota, Shin; Wada, Kenji; Uchida-Kobayashi, Sawako; Kawada, Norifumi; Horinaka, Hiromichi

2017-01-01

Indocyanine green (ICG) accumulation in hepatocellular carcinoma means tumors can be located by fluorescence. However, because of light scattering, it is difficult to detect ICG fluorescence from outside the body. We propose a new fluorescence imaging method that detects changes in the intensity of ICG fluorescence by ultrasound-induced temperature changes. ICG fluorescence intensity decreases as the temperature rises. Therefore, it should theoretically be possible to detect tissue distribution of ICG using ultrasound to heat tissue, moving the point of ultrasound transmission, and monitoring changes in fluorescence intensity. A new probe was adapted for clinical application. It consisted of excitation light from a laser, fluorescence sensing through a light pipe, and heating by ultrasound. We applied the probe to bovine liver to image the accumulation of ICG. ICG emits fluorescence (820 nm) upon light irradiation (783 nm). With a rise in temperature, the fluorescence intensity of ICG decreased by 0.85 %/°C. The distribution of fluorescent ICG was detected using an ultrasonic warming method in a new integrated probe. Modulating fluorescence by changing the temperature using ultrasound can determine where ICG accumulates at a depth, highlighting its potential as a means to locate hepatocellular carcinoma.
New developments in paediatric cardiac functional ultrasound imaging.

Science.gov (United States)

de Korte, Chris L; Nillesen, Maartje M; Saris, Anne E C M; Lopata, Richard G P; Thijssen, Johan M; Kapusta, Livia

2014-07-01

Ultrasound imaging can be used to estimate the morphology as well as the motion and deformation of tissues. If the interrogated tissue is actively deforming, this deformation is directly related to its function and quantification of this deformation is normally referred as 'strain imaging'. Tissue can also be deformed by applying an internal or external force and the resulting, induced deformation is a function of the mechanical tissue characteristics. In combination with the load applied, these strain maps can be used to estimate or reconstruct the mechanical properties of tissue. This technique was named 'elastography' by Ophir et al. in 1991. Elastography can be used for atherosclerotic plaque characterisation, while the contractility of the heart or skeletal muscles can be assessed with strain imaging. Rather than using the conventional video format (DICOM) image information, radio frequency (RF)-based ultrasound methods enable estimation of the deformation at higher resolution and with higher precision than commercial methods using Doppler (tissue Doppler imaging) or video image data (2D speckle tracking methods). However, the improvement in accuracy is mainly achieved when measuring strain along the ultrasound beam direction, so it has to be considered a 1D technique. Recently, this method has been extended to multiple directions and precision further improved by using spatial compounding of data acquired at multiple beam steered angles. Using similar techniques, the blood velocity and flow can be determined. RF-based techniques are also beneficial for automated segmentation of the ventricular cavities. In this paper, new developments in different techniques of quantifying cardiac function by strain imaging, automated segmentation, and methods of performing blood flow imaging are reviewed and their application in paediatric cardiology is discussed.
3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis

Science.gov (United States)

Yang, Xiaofeng; Rossi, Peter; Shelton, Joseph; Bruner, Debrorah; Tridandapani, Srini; Liu, Tian

2014-03-01

Radiation-induced vaginal fibrosis is a debilitating side-effect affecting up to 80% of women receiving radiotherapy for their gynecological (GYN) malignancies. Despite the significant incidence and severity, little research has been conducted to identify the pathophysiologic changes of vaginal toxicity. In a previous study, we have demonstrated that ultrasound Nakagami shape and PDF parameters can be used to quantify radiation-induced vaginal toxicity. These Nakagami parameters are derived from the statistics of ultrasound backscattered signals to capture the physical properties (e.g., arrangement and distribution) of the biological tissues. In this paper, we propose to expand this Nakagami imaging concept from 2D to 3D to fully characterize radiation-induced changes to the vaginal wall within the radiation treatment field. A pilot study with 5 post-radiotherapy GYN patients was conducted using a clinical ultrasound scanner (6 MHz) with a mechanical stepper. A serial of 2D ultrasound images, with radio-frequency (RF) signals, were acquired at 1 mm step size. The 2D Nakagami shape and PDF parameters were calculated from the RF signal envelope with a sliding window, and then 3D Nakagami parameter images were generated from the parallel 2D images. This imaging method may be useful as we try to monitor radiation-induced vaginal injury, and address vaginal toxicities and sexual dysfunction in women after radiotherapy for GYN malignancies.
Compact Beamformer Design with High Frame Rate for Ultrasound Imaging

Directory of Open Access Journals (Sweden)

Jun Luo

2014-04-01

Full Text Available In medical field, two-dimension ultrasound images are widely used in clinical diagnosis. Beamformer is critical in determining the complexity and performance of an ultrasound imaging system. Different from traditional means implemented with separated chips, a compact beamformer with 64 effective channels in a single moderate Field Programmable Gate Array has been presented in this paper. The compactness is acquired by employing receive synthetic aperture, harmonic imaging, time sharing and linear interpolation. Besides that, multi-beams method is used to improve the frame rate of the ultrasound imaging system. Online dynamic configuration is employed to expand system’s flexibility to two kinds of transducers with multi-scanning modes. The design is verified on a prototype scanner board. Simulation results have shown that on-chip memories can be saved and the frame rate can be improved on the case of 64 effective channels which will meet the requirement of real-time application.
Psychomotor skills in medical ultrasound imaging: an analysis of the core skill set.

Science.gov (United States)

Nicholls, Delwyn; Sweet, Linda; Hyett, Jon

2014-08-01

Sonographers use psychomotor skills to perform medical ultrasound examinations. Psychomotor skills describe voluntary movements of the limb, joints, and muscles in response to sensory stimuli and are regulated by the motor neural cortex in the brain. We define a psychomotor skill in relation to medical ultrasound imaging as "the unique mental and motor activities required to execute a manual task safely and efficiently for each clinical situation." Skills in clinical ultrasound practice may be open or closed; most skills used in medical ultrasound imaging are open. Open skills are both complex and multidimensional. Visuomotor and visuospatial psychomotor skills are central components of medical ultrasound imaging. Both types of skills rely on learners having a visual exemplar or standard of performance with which to reference their skill performance and evaluate anatomic structures. These are imperative instructional design principles when teaching psychomotor skills. © 2014 by the American Institute of Ultrasound in Medicine.
WE-D-18C-01: Art of Imaging: Diagnostic Ultrasound Image Artifacts

Energy Technology Data Exchange (ETDEWEB)

Zagzebski, J [University of Wisconsin, Madison, WI (United States); Lu, Z [University of Chicago, Chicago, IL (United States)

2014-06-15

Assumptions followed during construction of B-mode and color flow images are that the pulse-echo transit time can be converted to reflector depth through uniform tissue models, echoes originate only from locations along the transmit-receive axes of pulse propagation, and first order correction schemes adequately account for acoustic wave attenuation and absorption. The latter allows the display brightness to encode tissue echogenicity. This course will challenge participants to identify imaging artifacts whose origins stem from the more complex and realistic propagating and scattering conditions common in clinical ultrasound. Speckle, a very common artifact but a clinically employed feature, originates from simultaneous echoes from diffuse scatterers and is a result of coherent detection of signals. One of the most bothersome artifacts are those due to reverberations especially that originating from superficial tissue interfaces. Methods to overcome these will be discussed. This presentation also will describe and illustrate speed of sound, refraction, enhancement, shadowing, mirroring, beam width, beam-forming, and slice thickness artifacts. All are useful examples of limitations introduced by acoustic waves propagating through complex tissue paths. New formats for physician board certification exams are demanding the inclusion of image-based examples of ultrasound physics. Instructors' knowledge of, and access to examples of ultrasound artifacts are important in this effort. The presentation will incorporate an audience response system to challenge participants in correct identification of some of these artifacts. Learning Objectives: Review basic mechanisms for producing ultrasound images. Identify the etiology of speckle, reverberation noise, beam width and slice thickness artifacts, and artifacts associated with pulse propagation. Discuss methods that reduce the impact of artifacts OR employ artifacts effectively to facilitate clinical diagnosis.
Estimation of bladder wall location in ultrasound images.

Science.gov (United States)

Topper, A K; Jernigan, M E

1991-05-01

A method of automatically estimating the location of the bladder wall in ultrasound images is proposed. Obtaining this estimate is intended to be the first stage in the development of an automatic bladder volume calculation system. The first step in the bladder wall estimation scheme involves globally processing the images using standard image processing techniques to highlight the bladder wall. Separate processing sequences are required to highlight the anterior bladder wall and the posterior bladder wall. The sequence to highlight the anterior bladder wall involves Gaussian smoothing and second differencing followed by zero-crossing detection. Median filtering followed by thresholding and gradient detection is used to highlight as much of the rest of the bladder wall as was visible in the original images. Then a 'bladder wall follower'--a line follower with rules based on the characteristics of ultrasound imaging and the anatomy involved--is applied to the processed images to estimate the bladder wall location by following the portions of the bladder wall which are highlighted and filling in the missing segments. The results achieved using this scheme are presented.
Ultrasound imaging of sports-related musculoskeletal injuries

International Nuclear Information System (INIS)

Craig, J.G.; Holsbeek, M.T. van; Gauthier, T.P.; Cook, W.J.

2006-01-01

Sports-related injuries of the musculoskeletal system affect millions of individuals every year. Integrating high-frequency Tissue Harmonic Imaging ultrasound with MRI and CT gives the greatest opportunity for diagnosing specific injuries. (orig.)
Interventional ultrasound

International Nuclear Information System (INIS)

VanSonnenberg, E.

1987-01-01

This book contains 12 chapters and several case studies. Some of the chapter titles are: The Interplay of Ultrasound and Computed Tomography in the Planning and Execution of Interventional Procedures: Ulltrasound Guided Biopsy; Interventioal Genitourinary Sonography; Diagnosis and Treatment of Pericardial Effusion Using Ultrasonic Guidance; and New Ultrasound-Guided Interventional Procedures--Cholecystostomy, Pancreatography, Gastrostomy
SU-G-BRA-01: A Real-Time Tumor Localization and Guidance Platform for Radiotherapy Using US and MRI

International Nuclear Information System (INIS)

Bednarz, B; Culberson, W; Bassetti, M; McMillan, A; Matrosic, C; Shepard, A; Zagzebski, J; Smith, S; Lee, W; Mills, D; Cao, K; Wang, B; Fiveland, E; Darrow, R; Foo, T

2016-01-01

Purpose: To develop and validate a real-time motion management platform for radiotherapy that directly tracks tumor motion using ultrasound and MRI. This will be a cost-effective and non-invasive real-time platform combining the excellent temporal resolution of ultrasound with the excellent soft-tissue contrast of MRI. Methods: A 4D planar ultrasound acquisition during the treatment that is coupled to a pre-treatment calibration training image set consisting of a simultaneous 4D ultrasound and 4D MRI acquisition. The image sets will be rapidly matched using advanced image and signal processing algorithms, allowing the display of virtual MR images of the tumor/organ motion in real-time from an ultrasound acquisition. Results: The completion of this work will result in several innovations including: a (2D) patch-like, MR and LINAC compatible 4D planar ultrasound transducer that is electronically steerable for hands-free operation to provide real-time virtual MR and ultrasound imaging for motion management during radiation therapy; a multi- modal tumor localization strategy that uses ultrasound and MRI; and fast and accurate image processing algorithms that provide real-time information about the motion and location of tumor or related soft-tissue structures within the patient. Conclusion: If successful, the proposed approach will provide real-time guidance for radiation therapy without degrading image or treatment plan quality. The approach would be equally suitable for image-guided proton beam or heavy ion-beam therapy. This work is partially funded by NIH grant R01CA190298
SU-G-BRA-01: A Real-Time Tumor Localization and Guidance Platform for Radiotherapy Using US and MRI

Energy Technology Data Exchange (ETDEWEB)

Bednarz, B; Culberson, W; Bassetti, M; McMillan, A; Matrosic, C; Shepard, A; Zagzebski, J [University of Wisconsin, Madison, WI (United States); Smith, S; Lee, W; Mills, D; Cao, K; Wang, B; Fiveland, E; Darrow, R; Foo, T [GE Global Research Center, Niskayuna, NY (United States)

2016-06-15

Purpose: To develop and validate a real-time motion management platform for radiotherapy that directly tracks tumor motion using ultrasound and MRI. This will be a cost-effective and non-invasive real-time platform combining the excellent temporal resolution of ultrasound with the excellent soft-tissue contrast of MRI. Methods: A 4D planar ultrasound acquisition during the treatment that is coupled to a pre-treatment calibration training image set consisting of a simultaneous 4D ultrasound and 4D MRI acquisition. The image sets will be rapidly matched using advanced image and signal processing algorithms, allowing the display of virtual MR images of the tumor/organ motion in real-time from an ultrasound acquisition. Results: The completion of this work will result in several innovations including: a (2D) patch-like, MR and LINAC compatible 4D planar ultrasound transducer that is electronically steerable for hands-free operation to provide real-time virtual MR and ultrasound imaging for motion management during radiation therapy; a multi- modal tumor localization strategy that uses ultrasound and MRI; and fast and accurate image processing algorithms that provide real-time information about the motion and location of tumor or related soft-tissue structures within the patient. Conclusion: If successful, the proposed approach will provide real-time guidance for radiation therapy without degrading image or treatment plan quality. The approach would be equally suitable for image-guided proton beam or heavy ion-beam therapy. This work is partially funded by NIH grant R01CA190298.
Integrated photoacoustic/ultrasound imaging: applications and new techniques

NARCIS (Netherlands)

van den Berg, P.J.

2017-01-01

Photoacoustic imaging (PAI) is a unique combination of optical sensitivity to tissue chromophores like hemoglobin, and ultrasonic resolution. Research in this PhD thesis is made possible by the development of a probe that combines PAI with regular ultrasound imaging. This probe is handheld and
Three-dimensional ultrasound strain imaging of skeletal muscles

NARCIS (Netherlands)

Gijsbertse, Kaj; Sprengers, Andre M.; Nillesen, Maartje; Hansen, Hendrik H.G.; Verdonschot, Nico; De Korte, Chris L.

2015-01-01

Muscle contraction is characterized by large deformation and translation, which requires a multi-dimensional imaging modality to reveal its behavior. Previous work on ultrasound strain imaging of the muscle contraction was limited to 2D and bi-plane techniques. In this study, a three-dimensional
Imaging of degenerative and posttraumatic disease in the shoulder joint with ultrasound

International Nuclear Information System (INIS)

Zanetti, Marco; Hodler, Juerg

2000-01-01

This article reviews the examination technique of shoulder ultrasound, normal and abnormal ultrasound findings in acute (posttraumatic) and chronic (degenerative) lesions. Moreover, it reviews the effectiveness of ultrasound in relation to magnetic resonance (MR) imaging. Most authors report that full-thickness tears of the supraspinatus can reliably be diagnosed by ultrasound. However, the simple diagnosis of a full-thickness rotator cuff tear is no longer sufficient for surgical management. The precise localization and size of rotator cuff tears as well as the extent of muscle degeneration is important for surgical planning. For this aspect and for partial-thickness tears of the supraspinatus, for subscapularis lesions as well as for lesions of the long biceps tendons there is no consensus regarding the diagnostic value of ultrasound. To the present, ultrasound (contrary to MR imaging) has failed to demonstrate that it consistently influences the clinician's degree of confidence in the clinical diagnosis or the treatment plan. Therefore, some orthopedic surgeons prefer MR imaging to ultrasound in the evaluation of rotator cuff tears and other abnormalities of the glenohumeral joint. Moreover, MR imaging, especially when combined with arthrography, represents a one-step investigation, which not only allows for assessment of rotator cuff lesion but also of lesions of the labrum (Bankart lesions, SLAP lesions), the joint capsule and the biceps tendon. It also demonstrates muscle atrophy, which represents an important predictor of surgical outcome in rotator cuff repair
Imaging of degenerative and posttraumatic disease in the shoulder joint with ultrasound

Energy Technology Data Exchange (ETDEWEB)

Zanetti, Marco E-mail: mzanetti@balgrist.unizh.ch; Hodler, Juerg

2000-08-01

This article reviews the examination technique of shoulder ultrasound, normal and abnormal ultrasound findings in acute (posttraumatic) and chronic (degenerative) lesions. Moreover, it reviews the effectiveness of ultrasound in relation to magnetic resonance (MR) imaging. Most authors report that full-thickness tears of the supraspinatus can reliably be diagnosed by ultrasound. However, the simple diagnosis of a full-thickness rotator cuff tear is no longer sufficient for surgical management. The precise localization and size of rotator cuff tears as well as the extent of muscle degeneration is important for surgical planning. For this aspect and for partial-thickness tears of the supraspinatus, for subscapularis lesions as well as for lesions of the long biceps tendons there is no consensus regarding the diagnostic value of ultrasound. To the present, ultrasound (contrary to MR imaging) has failed to demonstrate that it consistently influences the clinician's degree of confidence in the clinical diagnosis or the treatment plan. Therefore, some orthopedic surgeons prefer MR imaging to ultrasound in the evaluation of rotator cuff tears and other abnormalities of the glenohumeral joint. Moreover, MR imaging, especially when combined with arthrography, represents a one-step investigation, which not only allows for assessment of rotator cuff lesion but also of lesions of the labrum (Bankart lesions, SLAP lesions), the joint capsule and the biceps tendon. It also demonstrates muscle atrophy, which represents an important predictor of surgical outcome in rotator cuff repair.

Recent advances of ultrasound imaging in dentistry--a review of the literature.

Science.gov (United States)

Marotti, Juliana; Heger, Stefan; Tinschert, Joachim; Tortamano, Pedro; Chuembou, Fabrice; Radermacher, Klaus; Wolfart, Stefan

2013-06-01

Ultrasonography as an imaging modality in dentistry has been extensively explored in recent years due to several advantages that diagnostic ultrasound provides. It is a non-invasive, inexpensive, painless method and unlike X-ray, it does not cause harmful ionizing radiation. Ultrasound has a promising future as a diagnostic imaging tool in all specialties in dentistry, for both hard and soft tissue detection. The aim of this review is to provide the scientific community and clinicians with an overview of the most recent advances of ultrasound imaging in dentistry. The use of ultrasound is described and discussed in the fields of dental scanning, caries detection, dental fractures, soft tissue and periapical lesions, maxillofacial fractures, periodontal bony defects, gingival and muscle thickness, temporomandibular disorders, and implant dentistry. Copyright © 2013 Elsevier Inc. All rights reserved.
The use of image-guidance during transsphenoidal pituitary surgery in the United States

Science.gov (United States)

Chung, Thomas K.; Riley, Kristen O.

2015-01-01

Background: Intraoperative image guidance is a useful modality for transsphenoidal pituitary surgery. However, the outcomes associated with this technology have not been systematically evaluated. Objective: The purpose of the study was to quantify complication rates with and without the use of image guidance during transsphenoidal pituitary surgery using a nationwide database with broadly applicable results. Methods: A retrospective analysis of the Nationwide Inpatient Sample was performed from 2007 to 2011. Transsphenoidal pituitary resections for adenomas were identified by International Classification of Diseases-9th Revision, Clinical Modification code. The effect of image guidance on cerebrospinal fluid (CSF) leak complications and cost-benefit was analyzed. Results: A total of 48,848 transsphenoidal pituitary resections were identified, of which 77.5% were partial resections and 22.5% were complete. Pathologic indications included benign (89.3%), malignant primary (0.6%), and malignant secondary (0.4%). Complications included same-stay death (0.4%), CSF leak (8.8%), postoperative CSF rhinorrhea (1.9%), diabetes insipidus (12.4%), and meningitis (0.4%). Image guidance was employed in 7% (n = 3401) of all cases. When analyzed by modality, computed tomography (CT)-assisted procedures had lower CSF rhinorrhea rates (1.1%) compared with cases with no image guidance (1.9%), whereas magnetic resonance (MR)-assisted procedures had the highest rates (2.7%, χ2 p surgery had significantly shorter length of stay (2.9 days) versus no image guidance (3.7 days, p surgery is associated with a lower rate of CSF leak, shorter length of stay, and lower cost compared with patients without image guidance. Further studies that control for severity and extent of disease are warranted to confirm this finding. PMID:25975254
MO-DE-202-01: Image-Guided Focused Ultrasound Surgery and Therapy

Energy Technology Data Exchange (ETDEWEB)

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

2016-06-15

At least three major trends in surgical intervention have emerged over the last decade: a move toward more minimally invasive (or non-invasive) approach to the surgical target; the development of high-precision treatment delivery techniques; and the increasing role of multi-modality intraoperative imaging in support of such procedures. This symposium includes invited presentations on recent advances in each of these areas and the emerging role for medical physics research in the development and translation of high-precision interventional techniques. The four speakers are: Keyvan Farahani, “Image-guided focused ultrasound surgery and therapy” Jeffrey H. Siewerdsen, “Advances in image registration and reconstruction for image-guided neurosurgery” Tina Kapur, “Image-guided surgery and interventions in the advanced multimodality image-guided operating (AMIGO) suite” Raj Shekhar, “Multimodality image-guided interventions: Multimodality for the rest of us” Learning Objectives: Understand the principles and applications of HIFU in surgical ablation. Learn about recent advances in 3D–2D and 3D deformable image registration in support of surgical safety and precision. Learn about recent advances in model-based 3D image reconstruction in application to intraoperative 3D imaging. Understand the multi-modality imaging technologies and clinical applications investigated in the AMIGO suite. Understand the emerging need and techniques to implement multi-modality image guidance in surgical applications such as neurosurgery, orthopaedic surgery, vascular surgery, and interventional radiology. Research supported by the NIH and Siemens Healthcare.; J. Siewerdsen; Grant Support - National Institutes of Health; Grant Support - Siemens Healthcare; Grant Support - Carestream Health; Advisory Board - Carestream Health; Licensing Agreement - Carestream Health; Licensing Agreement - Elekta Oncology.; T. Kapur, P41EB015898; R. Shekhar, Funding: R42CA137886 and R41CA192504
MO-DE-202-01: Image-Guided Focused Ultrasound Surgery and Therapy

International Nuclear Information System (INIS)

Farahani, K.

2016-01-01

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

Science.gov (United States)

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

2006-03-01

This paper presents a novel ultrasound-guided computer system for arthroscopic surgery of the shoulder joint. Intraoperatively, the system tracks and displays the surgical instruments, such as arthroscope and arthroscopic burrs, relative to the anatomy of the patient. The purpose of this system is to improve the surgeon's perception of the three-dimensional space within the anatomy of the patient in which the instruments are manipulated and to provide guidance towards the targeted anatomy. Pre-operatively, computed tomography images of the patient are acquired to construct virtual threedimensional surface models of the shoulder bone structure. Intra-operatively, live ultrasound images of pre-selected regions of the shoulder are captured using an ultrasound probe whose three-dimensional position is tracked by an optical camera. These images are used to register the surface model to the anatomy of the patient in the operating room. An initial alignment is obtained by matching at least three points manually selected on the model to their corresponding points identified on the ultrasound images. The registration is then improved with an iterative closest point or a sequential least squares estimation technique. In the present study the registration results of these techniques are compared. After the registration, surgical instruments are displayed relative to the surface model of the patient on a graphical screen visible to the surgeon. Results of laboratory experiments on a shoulder phantom indicate acceptable registration results and sufficiently fast overall system performance to be applicable in the operating room.
GPU-Based Block-Wise Nonlocal Means Denoising for 3D Ultrasound Images

Directory of Open Access Journals (Sweden)

Liu Li

2013-01-01

Full Text Available Speckle suppression plays an important role in improving ultrasound (US image quality. While lots of algorithms have been proposed for 2D US image denoising with remarkable filtering quality, there is relatively less work done on 3D ultrasound speckle suppression, where the whole volume data rather than just one frame needs to be considered. Then, the most crucial problem with 3D US denoising is that the computational complexity increases tremendously. The nonlocal means (NLM provides an effective method for speckle suppression in US images. In this paper, a programmable graphic-processor-unit- (GPU- based fast NLM filter is proposed for 3D ultrasound speckle reduction. A Gamma distribution noise model, which is able to reliably capture image statistics for Log-compressed ultrasound images, was used for the 3D block-wise NLM filter on basis of Bayesian framework. The most significant aspect of our method was the adopting of powerful data-parallel computing capability of GPU to improve the overall efficiency. Experimental results demonstrate that the proposed method can enormously accelerate the algorithm.
Exploring the effects of gravity on tongue motion using ultrasound image sequences

Science.gov (United States)

Stone, Maureen; Crouse, Ulla; Sutton, Marty

2002-05-01

Our goal in the research was to explore the effect that gravity had on the vocal-tract system by using ultrasound data collected in the upright and supine positions. All potential subjects were given an ultrasound pretest to determine whether they could repeat a series of 3-4 words precise enough to allow an accurate series of images to be collected. Out of these potential subjects, approximately 5-7 subjects were eventually used in the research. The method of collecting ultrasound data required the immobilization of the patient by restraining their neck in a custom fitted neck restraint. The neck restraint held an ultrasound transducer positioned at a critical angle underneath the patients' lower jawbone, which served to reduce errors and increase image resolution. To accurately analyze the series of images collected from ultrasound imaging, the surfaces of the tongue were digitized and tongue motion was time-aligned across the upright and supine sequences. Comparisons between the upright and supine data were then made by using L2 norms to determine averages and differences regarding the behavior between the two positions. Curves and locations of the maximum and minimum differences will be discussed.
General Ultrasound Imaging

Medline Plus

Full Text Available ... of page How is the procedure performed? For most ultrasound exams, you will be positioned lying face- ... Ultrasound examinations are painless and easily tolerated by most patients. Ultrasound exams in which the transducer is ...
Versatile robotic probe calibration for position tracking in ultrasound imaging

International Nuclear Information System (INIS)

Bø, Lars Eirik; Hofstad, Erlend Fagertun; Lindseth, Frank; Hernes, Toril A N

2015-01-01

Within the field of ultrasound-guided procedures, there are a number of methods for ultrasound probe calibration. While these methods are usually developed for a specific probe, they are in principle easily adapted to other probes. In practice, however, the adaptation often proves tedious and this is impractical in a research setting, where new probes are tested regularly. Therefore, we developed a method which can be applied to a large variety of probes without adaptation. The method used a robot arm to move a plastic sphere submerged in water through the ultrasound image plane, providing a slow and precise movement. The sphere was then segmented from the recorded ultrasound images using a MATLAB programme and the calibration matrix was computed based on this segmentation in combination with tracking information. The method was tested on three very different probes demonstrating both great versatility and high accuracy. (paper)
Versatile robotic probe calibration for position tracking in ultrasound imaging

Science.gov (United States)

Eirik Bø, Lars; Fagertun Hofstad, Erlend; Lindseth, Frank; Hernes, Toril A. N.

2015-05-01

Within the field of ultrasound-guided procedures, there are a number of methods for ultrasound probe calibration. While these methods are usually developed for a specific probe, they are in principle easily adapted to other probes. In practice, however, the adaptation often proves tedious and this is impractical in a research setting, where new probes are tested regularly. Therefore, we developed a method which can be applied to a large variety of probes without adaptation. The method used a robot arm to move a plastic sphere submerged in water through the ultrasound image plane, providing a slow and precise movement. The sphere was then segmented from the recorded ultrasound images using a MATLAB programme and the calibration matrix was computed based on this segmentation in combination with tracking information. The method was tested on three very different probes demonstrating both great versatility and high accuracy.
Sampling system for in vivo ultrasound images

DEFF Research Database (Denmark)

Jensen, Jorgen Arendt; Mathorne, Jan

1991-01-01

Newly developed algorithms for processing medical ultrasound images use the high frequency sampled transducer signal. This paper describes demands imposed on a sampling system suitable for acquiring such data and gives details about a prototype constructed. It acquires full clinical images...... at a sampling frequency of 20 MHz with a resolution of 12 bits. The prototype can be used for real time image processing. An example of a clinical in vivo image is shown and various aspects of the data acquisition process are discussed....
Transfer Learning with Convolutional Neural Networks for Classification of Abdominal Ultrasound Images.

Science.gov (United States)

Cheng, Phillip M; Malhi, Harshawn S

2017-04-01

The purpose of this study is to evaluate transfer learning with deep convolutional neural networks for the classification of abdominal ultrasound images. Grayscale images from 185 consecutive clinical abdominal ultrasound studies were categorized into 11 categories based on the text annotation specified by the technologist for the image. Cropped images were rescaled to 256 × 256 resolution and randomized, with 4094 images from 136 studies constituting the training set, and 1423 images from 49 studies constituting the test set. The fully connected layers of two convolutional neural networks based on CaffeNet and VGGNet, previously trained on the 2012 Large Scale Visual Recognition Challenge data set, were retrained on the training set. Weights in the convolutional layers of each network were frozen to serve as fixed feature extractors. Accuracy on the test set was evaluated for each network. A radiologist experienced in abdominal ultrasound also independently classified the images in the test set into the same 11 categories. The CaffeNet network classified 77.3% of the test set images accurately (1100/1423 images), with a top-2 accuracy of 90.4% (1287/1423 images). The larger VGGNet network classified 77.9% of the test set accurately (1109/1423 images), with a top-2 accuracy of VGGNet was 89.7% (1276/1423 images). The radiologist classified 71.7% of the test set images correctly (1020/1423 images). The differences in classification accuracies between both neural networks and the radiologist were statistically significant (p convolutional neural networks may be used to construct effective classifiers for abdominal ultrasound images.
Prostate Ultrasound

Medline Plus

Full Text Available ... Physician Resources Professions Site Index A-Z Ultrasound - Prostate Ultrasound of the prostate uses sound waves to ... Ultrasound Imaging? What is Ultrasound Imaging of the Prostate? Ultrasound is safe and painless, and produces pictures ...
Impact of Image Guidance on Outcomes After External Beam Radiotherapy for Localized Prostate Cancer

International Nuclear Information System (INIS)

Kupelian, Patrick A.; Willoughby, Twyla R.; Reddy, Chandana A.; Klein, Eric A.; Mahadevan, Arul

2008-01-01

Purpose: To verify whether rectal distention at the time of planning impacts outcomes in patients with localized prostate cancer treated with daily image guidance. Methods and Materials: Between 1998 and 2002, a total of 488 prostate cancer patients were treated with intensity-modulated radiotherapy. The radiation dose was 70 Gy delivered at 2.5 Gy per fraction in all cases. All cases were treated with a 4-mm margin posteriorly. In all cases the total rectal volume documented on the CT scan was used for treatment planning. No special bowel preparation instructions were given, either for the simulation or the daily treatments. Before each daily treatment, alignment of the prostate was performed with the B-mode acquisition and targeting (BAT) transabdominal ultrasound system. The median follow-up for all 488 patients was 60 months (range, 24-96 months). Results: For all patients the biochemical relapse-free survival (bRFS) rate at 5 years was 86%. The 5-year bRFS rate for the rectal distention 3 , 50 to 3 , and ≥100 cm 3 groups was 90%, 83%, and 85%, respectively (p = 0.18). To adjust for other potential variables affecting bRFS rates, a multivariate time-to-failure analysis using the Cox proportional hazards model was performed. Rectal distention was not an independent predictor of biochemical failure on multivariate analysis (p = 0.80). Rectal distention was not a predictor of rectal or urinary toxicity. Conclusion: The use of daily image guidance eliminates errors such as rectal distention at the initial planning stage that can affect outcomes after radiotherapy for localized prostate cancer
Deconvolution of In Vivo Ultrasound B-Mode Images

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt; Stage, Bjarne; Mathorne, Jan

1993-01-01

An algorithm for deconvolution of medical ultrasound images is presented. The procedure involves estimation of the basic one-dimensional ultrasound pulse, determining the ratio of the covariance of the noise to the covariance of the reflection signal, and finally deconvolution of the rf signal from...... the transducer. Using pulse and covariance estimators makes the approach self-calibrating, as all parameters for the procedure are estimated from the patient under investigation. An example of use on a clinical, in-vivo image is given. A 2 × 2 cm region of the portal vein in a liver is deconvolved. An increase...... in axial resolution by a factor of 2.4 is obtained. The procedure can also be applied to whole images, when it is ensured that the rf signal is properly measured. A method for doing that is outlined....
Evaluation of a mobile augmented reality application for image guidance of neurosurgical interventions.

Science.gov (United States)

Kramers, Matthew; Armstrong, Ryan; Bakhshmand, Saeed M; Fenster, Aaron; de Ribaupierre, Sandrine; Eagleson, Roy

2014-01-01

Image guidance can provide surgeons with valuable contextual information during a medical intervention. Often, image guidance systems require considerable infrastructure, setup-time, and operator experience to be utilized. Certain procedures performed at bedside are susceptible to navigational errors that can lead to complications. We present an application for mobile devices that can provide image guidance using augmented reality to assist in performing neurosurgical tasks. A methodology is outlined that evaluates this mode of visualization from the standpoint of perceptual localization, depth estimation, and pointing performance, in scenarios derived from a neurosurgical targeting task. By measuring user variability and speed we can report objective metrics of performance for our augmented reality guidance system.
SU-E-J-06: Additional Imaging Guidance Dose to Patient Organs Resulting From X-Ray Tubes Used in CyberKnife Image Guidance System

Energy Technology Data Exchange (ETDEWEB)

Sullivan, A; Ding, G [Vanderbilt University, Nashville, TN (United States)

2015-06-15

Purpose: The use of image-guided radiation therapy (IGRT) has become increasingly common, but the additional radiation exposure resulting from repeated image guidance procedures raises concerns. Although there are many studies reporting imaging dose from different image guidance devices, imaging dose for the CyberKnife Robotic Radiosurgery System is not available. This study provides estimated organ doses resulting from image guidance procedures on the CyberKnife system. Methods: Commercially available Monte Carlo software, PCXMC, was used to calculate average organ doses resulting from x-ray tubes used in the CyberKnife system. There are seven imaging protocols with kVp ranging from 60 – 120 kV and 15 mAs for treatment sites in the Cranium, Head and Neck, Thorax, and Abdomen. The output of each image protocol was measured at treatment isocenter. For each site and protocol, Adult body sizes ranging from anorexic to extremely obese were simulated since organ dose depends on patient size. Doses for all organs within the imaging field-of-view of each site were calculated for a single image acquisition from both of the orthogonal x-ray tubes. Results: Average organ doses were <1.0 mGy for every treatment site and imaging protocol. For a given organ, dose increases as kV increases or body size decreases. Higher doses are typically reported for skeletal components, such as the skull, ribs, or clavicles, than for softtissue organs. Typical organ doses due to a single exposure are estimated as 0.23 mGy to the brain, 0.29 mGy to the heart, 0.08 mGy to the kidneys, etc., depending on the imaging protocol and site. Conclusion: The organ doses vary with treatment site, imaging protocol and patient size. Although the organ dose from a single image acquisition resulting from two orthogonal beams is generally insignificant, the sum of repeated image acquisitions (>100) could reach 10–20 cGy for a typical treatment fraction.
Deconvolution of in vivo ultrasound images

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt

1990-01-01

In an ultrasound image, the influence of the pulse and attenuation should be removed from the picture in order to display a more consistent and uniform image. The author describes an algorithm to remove the influence of the attenuated pulse on the image. The algorithm takes into account the varying...... pulse, noise in the acquired signal, and the changing reflectivity in the tissue. Both one- and two-dimensional processing can be implemented. The algorithm relies on prior knowledge of the pulse and of the covariance of the noise and the reflections. Algorithms to estimate these factors are given...
Thyroid Nodule Classification in Ultrasound Images by Fine-Tuning Deep Convolutional Neural Network.

Science.gov (United States)

Chi, Jianning; Walia, Ekta; Babyn, Paul; Wang, Jimmy; Groot, Gary; Eramian, Mark

2017-08-01

With many thyroid nodules being incidentally detected, it is important to identify as many malignant nodules as possible while excluding those that are highly likely to be benign from fine needle aspiration (FNA) biopsies or surgeries. This paper presents a computer-aided diagnosis (CAD) system for classifying thyroid nodules in ultrasound images. We use deep learning approach to extract features from thyroid ultrasound images. Ultrasound images are pre-processed to calibrate their scale and remove the artifacts. A pre-trained GoogLeNet model is then fine-tuned using the pre-processed image samples which leads to superior feature extraction. The extracted features of the thyroid ultrasound images are sent to a Cost-sensitive Random Forest classifier to classify the images into "malignant" and "benign" cases. The experimental results show the proposed fine-tuned GoogLeNet model achieves excellent classification performance, attaining 98.29% classification accuracy, 99.10% sensitivity and 93.90% specificity for the images in an open access database (Pedraza et al. 16), while 96.34% classification accuracy, 86% sensitivity and 99% specificity for the images in our local health region database.
FPGA-based reconfigurable processor for ultrafast interlaced ultrasound and photoacoustic imaging.

Science.gov (United States)

Alqasemi, Umar; Li, Hai; Aguirre, Andrés; Zhu, Quing

2012-07-01

In this paper, we report, to the best of our knowledge, a unique field-programmable gate array (FPGA)-based reconfigurable processor for real-time interlaced co-registered ultrasound and photoacoustic imaging and its application in imaging tumor dynamic response. The FPGA is used to control, acquire, store, delay-and-sum, and transfer the data for real-time co-registered imaging. The FPGA controls the ultrasound transmission and ultrasound and photoacoustic data acquisition process of a customized 16-channel module that contains all of the necessary analog and digital circuits. The 16-channel module is one of multiple modules plugged into a motherboard; their beamformed outputs are made available for a digital signal processor (DSP) to access using an external memory interface (EMIF). The FPGA performs a key role through ultrafast reconfiguration and adaptation of its structure to allow real-time switching between the two imaging modes, including transmission control, laser synchronization, internal memory structure, beamforming, and EMIF structure and memory size. It performs another role by parallel accessing of internal memories and multi-thread processing to reduce the transfer of data and the processing load on the DSP. Furthermore, because the laser will be pulsing even during ultrasound pulse-echo acquisition, the FPGA ensures that the laser pulses are far enough from the pulse-echo acquisitions by appropriate time-division multiplexing (TDM). A co-registered ultrasound and photoacoustic imaging system consisting of four FPGA modules (64-channels) is constructed, and its performance is demonstrated using phantom targets and in vivo mouse tumor models.

Second harmonic inversion for ultrasound contrast harmonic imaging

Energy Technology Data Exchange (ETDEWEB)

Pasovic, Mirza; Danilouchkine, Mike; Faez, Telli; Van Neer, Paul L M J; Van der Steen, Antonius F W; De Jong, Nico [THORAXCENTER, Department of Biomedical Engineering Ee2302, Erasmus MC, Rotterdam (Netherlands); Cachard, Christian; Basset, Olivier, E-mail: mirza.pasovic@creatis.insa-lyon.fr [CREATIS-LRMN, Universite de Lyon, INSA-Lyon, Universite Lyon 1, Inserm U630, CNRS UMR 5220 (France)

2011-06-07

Ultrasound contrast agents (UCAs) are small micro-bubbles that behave nonlinearly when exposed to an ultrasound wave. This nonlinear behavior can be observed through the generated higher harmonics in a back-scattered echo. In past years several techniques have been proposed to detect or image harmonics produced by UCAs. In these proposed works, the harmonics generated in the medium during the propagation of the ultrasound wave played an important role, since these harmonics compete with the harmonics generated by the micro-bubbles. We present a method for the reduction of the second harmonic generated during nonlinear-propagation-dubbed second harmonic inversion (SHI). A general expression for the suppression signals is also derived. The SHI technique uses two pulses, p' and p'', of the same frequency f{sub 0} and the same amplitude P{sub 0} to cancel out the second harmonic generated by nonlinearities of the medium. Simulations show that the second harmonic is reduced by 40 dB on a large axial range. Experimental SHI B-mode images, from a tissue-mimicking phantom and UCAs, show an improvement in the agent-to-tissue ratio (ATR) of 20 dB compared to standard second harmonic imaging and 13 dB of improvement in harmonic power Doppler.
Second harmonic inversion for ultrasound contrast harmonic imaging

International Nuclear Information System (INIS)

Pasovic, Mirza; Danilouchkine, Mike; Faez, Telli; Van Neer, Paul L M J; Van der Steen, Antonius F W; De Jong, Nico; Cachard, Christian; Basset, Olivier

2011-01-01

Ultrasound contrast agents (UCAs) are small micro-bubbles that behave nonlinearly when exposed to an ultrasound wave. This nonlinear behavior can be observed through the generated higher harmonics in a back-scattered echo. In past years several techniques have been proposed to detect or image harmonics produced by UCAs. In these proposed works, the harmonics generated in the medium during the propagation of the ultrasound wave played an important role, since these harmonics compete with the harmonics generated by the micro-bubbles. We present a method for the reduction of the second harmonic generated during nonlinear-propagation-dubbed second harmonic inversion (SHI). A general expression for the suppression signals is also derived. The SHI technique uses two pulses, p' and p'', of the same frequency f 0 and the same amplitude P 0 to cancel out the second harmonic generated by nonlinearities of the medium. Simulations show that the second harmonic is reduced by 40 dB on a large axial range. Experimental SHI B-mode images, from a tissue-mimicking phantom and UCAs, show an improvement in the agent-to-tissue ratio (ATR) of 20 dB compared to standard second harmonic imaging and 13 dB of improvement in harmonic power Doppler.
Cumulative phase delay imaging for contrast-enhanced ultrasound tomography

International Nuclear Information System (INIS)

Demi, Libertario; Van Sloun, Ruud J G; Wijkstra, Hessel; Mischi, Massimo

2015-01-01

Standard dynamic-contrast enhanced ultrasound (DCE-US) imaging detects and estimates ultrasound-contrast-agent (UCA) concentration based on the amplitude of the nonlinear (harmonic) components generated during ultrasound (US) propagation through UCAs. However, harmonic components generation is not specific to UCAs, as it also occurs for US propagating through tissue. Moreover, nonlinear artifacts affect standard DCE-US imaging, causing contrast to tissue ratio reduction, and resulting in possible misclassification of tissue and misinterpretation of UCA concentration. Furthermore, no contrast-specific modality exists for DCE-US tomography; in particular speed-of-sound changes due to UCAs are well within those caused by different tissue types. Recently, a new marker for UCAs has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental component is in fact observable for US propagating through UCAs, and is absent in tissue. In this paper, tomographic US images based on CPD are for the first time presented and compared to speed-of-sound US tomography. Results show the applicability of this marker for contrast specific US imaging, with cumulative phase delay imaging (CPDI) showing superior capabilities in detecting and localizing UCA, as compared to speed-of-sound US tomography. Cavities (filled with UCA) which were down to 1 mm in diameter were clearly detectable. Moreover, CPDI is free of the above mentioned nonlinear artifacts. These results open important possibilities to DCE-US tomography, with potential applications to breast imaging for cancer localization. (fast track communication)
Texture Feature Analysis for Different Resolution Level of Kidney Ultrasound Images

Science.gov (United States)

Kairuddin, Wan Nur Hafsha Wan; Mahmud, Wan Mahani Hafizah Wan

2017-08-01

Image feature extraction is a technique to identify the characteristic of the image. The objective of this work is to discover the texture features that best describe a tissue characteristic of a healthy kidney from ultrasound (US) image. Three ultrasound machines that have different specifications are used in order to get a different quality (different resolution) of the image. Initially, the acquired images are pre-processed to de-noise the speckle to ensure the image preserve the pixels in a region of interest (ROI) for further extraction. Gaussian Low- pass Filter is chosen as the filtering method in this work. 150 of enhanced images then are segmented by creating a foreground and background of image where the mask is created to eliminate some unwanted intensity values. Statistical based texture features method is used namely Intensity Histogram (IH), Gray-Level Co-Occurance Matrix (GLCM) and Gray-level run-length matrix (GLRLM).This method is depends on the spatial distribution of intensity values or gray levels in the kidney region. By using One-Way ANOVA in SPSS, the result indicated that three features (Contrast, Difference Variance and Inverse Difference Moment Normalized) from GLCM are not statistically significant; this concludes that these three features describe a healthy kidney characteristics regardless of the ultrasound image quality.
Ultrasound Image Quality Assessment: A framework for evaluation of clinical image quality

DEFF Research Database (Denmark)

Hemmsen, Martin Christian; Pedersen, Mads Møller; Nikolov, Svetoslav Ivanov

2010-01-01

Improvement of ultrasound images should be guided by their diagnostic value. Evaluation of clinical image quality is generally performed subjectively, because objective criteria have not yet been fully developed and accepted for the evaluation of clinical image quality. Based on recommendation 50...... information, which is fast enough to get sufficient number of scans under realistic operating conditions, so that statistical evaluation is valid and reliable....
A hybrid optical system for broadband imaging in guidance and control

Science.gov (United States)

Wu, Xiaofang; Jiang, Yuesong; Shen, Chunyan; Zhao, Yiming

2006-11-01

A binary optics method has been adopted to improve upon a conventional optical system in guidance and control, and a hybrid broadband imaging system that includes a binary surface is analyzed and evaluated by optical design software ZEMAX. The practical design shows that the introduction of binary optics can simplify the structure of the imaging system and reduce the size and weight of the broadband guidance and control system. Moreover, it can help to acquire images of radiation of different wavelengths from targets; hence it will result in improved overall performance of missiles in wars.
Noncontact ultrasound imaging applied to cortical bone phantoms

OpenAIRE

Bulman, J. B.; Ganezer, K. S.; Halcrow, P. W.; Neeson, Ian

2012-01-01

Purpose: The purpose of this paper was to take the first steps toward applying noncontact ultrasound (NCU) to the tasks of monitoring osteoporosis and quantitative ultrasound imaging (QUS) of cortical bone. The authors also focused on the advantages of NCU, such as its lack of reliance on a technologist to apply transducers and a layer of acoustical coupling gel, the ability of the transducers to operate autonomously as specified by preprogrammed software, and the likely reduction in statisti...
Resection of Cesarean Scar Pregnancy at Six Weeks of Gestation with Laminaria Cervical Dilatation under Sonographic and Hysteroscopic Guidance

Directory of Open Access Journals (Sweden)

Tatsuji Hoshino

2015-01-01

Full Text Available In cases of fetal heartbeat- (FHB- positive cesarean scar pregnancy (CSP, the embryo and placenta grow rapidly week by week. We experienced an FHB-positive CSP case at 6 weeks of gestation and assessed the CSP in detail with transvaginal ultrasound and transabdominal ultrasound (TAUS, preoperatively. We performed Laminaria cervical dilatation under TAUS guidance and performed hysteroscopic resection of the pregnancy conceptus and curettage under hysteroscopic and TAUS guidance. We identified the gestational sac attached to the cesarean scar pouch with small plane, decidua basalis, and chorionic villi and present the clinical history and other findings. We also reviewed the related literature and found 76 previous studies, with six cases of FHB-positive CSP that contained hysteroscopic color images of the CSP. We present a review of selected cases. The implantation site was the anterior wall in almost all cases. Cervical dilatation was mainly performed using a Hegar dilator; ours was the only case using Laminaria dilatation. Transcervical resections were performed mainly under ultrasound guidance, with only one case undergoing laparoscopy. Electrocoagulation was performed in three of the six cases.
Microbubble embedded with upconversion nanoparticles as a bimodal contrast agent for fluorescence and ultrasound imaging

International Nuclear Information System (INIS)

Jin, Birui; Lin, Min; You, Minli; Xu, Feng; Lu, Tianjian; Zong, Yujin; Wan, Mingxi; Duan, Zhenfeng

2015-01-01

Bimodal imaging offers additional imaging signal thus finds wide spread application in clinical diagnostic imaging. Fluorescence/ultrasound bimodal imaging contrast agent using fluorescent dyes or quantum dots for fluorescence signal has emerged as a promising method, which however requires visible light or UV irradiation resulting in photobleaching, photoblinking, auto-fluorescence and limited tissue penetration depth. To surmount these problems, we developed a novel bimodal contrast agent using layer-by-layer assembly of upconversion nanoparticles onto the surface of microbubbles. The resulting microbubbles with average size of 2 μm provide enhanced ultrasound echo for ultrasound imaging and upconversion emission upon near infrared irradiation for fluorescence imaging. The developed bimodal contrast agent holds great potential to be applied in ultrasound target technique for targeted diseases diagnostics and therapy. (paper)
Three-dimensional Image Fusion Guidance for Transjugular Intrahepatic Portosystemic Shunt Placement.

Science.gov (United States)

Tacher, Vania; Petit, Arthur; Derbel, Haytham; Novelli, Luigi; Vitellius, Manuel; Ridouani, Fourat; Luciani, Alain; Rahmouni, Alain; Duvoux, Christophe; Salloum, Chady; Chiaradia, Mélanie; Kobeiter, Hicham

2017-11-01

To assess the safety, feasibility and effectiveness of image fusion guidance with pre-procedural portal phase computed tomography with intraprocedural fluoroscopy for transjugular intrahepatic portosystemic shunt (TIPS) placement. All consecutive cirrhotic patients presenting at our interventional unit for TIPS creation from January 2015 to January 2016 were prospectively enrolled. Procedures were performed under general anesthesia in an interventional suite equipped with flat panel detector, cone-beam computed tomography (CBCT) and image fusion technique. All TIPSs were placed under image fusion guidance. After hepatic vein catheterization, an unenhanced CBCT acquisition was performed and co-registered with the pre-procedural portal phase CT images. A virtual path between hepatic vein and portal branch was made using the virtual needle path trajectory software. Subsequently, the 3D virtual path was overlaid on 2D fluoroscopy for guidance during portal branch cannulation. Safety, feasibility, effectiveness and per-procedural data were evaluated. Sixteen patients (12 males; median age 56 years) were included. Procedures were technically feasible in 15 of the 16 patients (94%). One procedure was aborted due to hepatic vein catheterization failure related to severe liver distortion. No periprocedural complications occurred within 48 h of the procedure. The median dose-area product was 91 Gy cm 2 , fluoroscopy time 15 min, procedure time 40 min and contrast media consumption 65 mL. Clinical benefit of the TIPS placement was observed in nine patients (56%). This study suggests that 3D image fusion guidance for TIPS is feasible, safe and effective. By identifying virtual needle path, CBCT enables real-time multiplanar guidance and may facilitate TIPS placement.
Real-time ultrasound-guided spinal anaesthesia: a prospective observational study of a new approach.

LENUS (Irish Health Repository)

Conroy, P H

2013-01-01

Identification of the subarachnoid space has traditionally been achieved by either a blind landmark-guided approach or using prepuncture ultrasound assistance. To assess the feasibility of performing spinal anaesthesia under real-time ultrasound guidance in routine clinical practice we conducted a single center prospective observational study among patients undergoing lower limb orthopaedic surgery. A spinal needle was inserted unassisted within the ultrasound transducer imaging plane using a paramedian approach (i.e., the operator held the transducer in one hand and the spinal needle in the other). The primary outcome measure was the success rate of CSF acquisition under real-time ultrasound guidance with CSF being located in 97 out of 100 consecutive patients within median three needle passes (IQR 1-6). CSF was not acquired in three patients. Subsequent attempts combining landmark palpation and pre-puncture ultrasound scanning resulted in successful spinal anaesthesia in two of these patients with the third patient requiring general anaesthesia. Median time from spinal needle insertion until intrathecal injection completion was 1.2 minutes (IQR 0.83-4.1) demonstrating the feasibility of this technique in routine clinical practice.
Ultrasound -- Pelvis

Medline Plus

Full Text Available ... Ultrasound - Pelvis Ultrasound imaging of the pelvis uses sound waves to produce pictures of the structures and ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...
TU-EF-210-04: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy

Energy Technology Data Exchange (ETDEWEB)

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

2015-06-15

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare.
TU-EF-210-04: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy

International Nuclear Information System (INIS)

Farahani, K.

2015-01-01

The use of therapeutic ultrasound to provide targeted therapy is an active research area that has a broad application scope. The invited talks in this session will address currently implemented strategies and protocols for both hyperthermia and ablation applications using therapeutic ultrasound. The role of both ultrasound and MRI in the monitoring and assessment of these therapies will be explored in both pre-clinical and clinical applications. Katherine Ferrara: High Intensity Focused Ultrasound, Drug Delivery, and Immunotherapy Rajiv Chopra: Translating Localized Doxorubicin Delivery to Pediatric Oncology using MRI-guided HIFU Elisa Konofagou: Real-time Ablation Monitoring and Lesion Quantification using Harmonic Motion Imaging Keyvan Farahani: AAPM Task Groups in Interventional Ultrasound Imaging and Therapy Learning Objectives: Understand the role of ultrasound in localized drug delivery and the effects of immunotherapy when used in conjunction with ultrasound therapy. Understand potential targeted drug delivery clinical applications including pediatric oncology. Understand the technical requirements for performing targeted drug delivery. Understand how radiation-force approaches can be used to both monitor and assess high intensity focused ultrasound ablation therapy. Understand the role of AAPM task groups in ultrasound imaging and therapies. Chopra: Funding from Cancer Prevention and Research Initiative of Texas (CPRIT), Award R1308 Evelyn and M.R. Hudson Foundation; Research Support from Research Contract with Philips Healthcare; COI are Co-founder of FUS Instruments Inc Ferrara: Supported by NIH, UCDavis and California (CIRM and BHCE) Farahani: In-kind research support from Philips Healthcare
First steps towards ultrasound-based motion compensation for imaging and therapy: calibration with an optical system and 4D PET imaging

Directory of Open Access Journals (Sweden)

Julia eSchwaab

2015-11-01

Full Text Available Target motion, particularly in the abdomen, due to respiration or patient movement is still a challenge in many diagnostic and therapeutic processes. Hence, methods to detect and compensate this motion are required. Diagnostic ultrasound represents a non-invasive and dose-free alternative to fluoroscopy, providing more information about internal target motion than respiration belt or optical tracking.The goal of this project is to develop an ultrasound based motion tracking for real time motion correction in radiation therapy and diagnostic imaging, notably in 4D positron emission tomography (PET. In this work, a workflow is established to enable the transformation of ultrasound tracking data to the coordinates of the treatment delivery or imaging system – even if the ultrasound probe is moving due to respiration. It is shown that the ultrasound tracking signal is equally adequate for 4D PET image reconstruction as the clinically used respiration belt and provides additional opportunities in this concern. Furthermore, it is demonstrated that the ultrasound probe being within the PET field of view generally has no relevant influence on the image quality. The accuracy and precision of all the steps in the calibration workflow for ultrasound tracking based 4D PET imaging are found to be in an acceptable range for clinical implementation. Eventually, we show in vitro that an ultrasound based motion tracking in absolute room coordinates with a moving US-transducer is feasible.
Plane-Wave Imaging Challenge in Medical Ultrasound

DEFF Research Database (Denmark)

Liebgott, Herve; Molares, Alfonso Rodriguez; Jensen, Jørgen Arendt

2016-01-01

for this effect, but comparing the different methods is difficult due to the lack of appropriate tools. PICMUS, the Plane-Wave Imaging Challenge in Medical Ultrasound aims to provide these tools. This paper describes the PICMUS challenge, its motivation, implementation, and metrics.......Plane-Wave imaging enables very high frame rates, up to several thousand frames per second. Unfortunately the lack of transmit focusing leads to reduced image quality, both in terms of resolution and contrast. Recently, numerous beamforming techniques have been proposed to compensate...
Ultrasound Imaging Techniques for Spatiotemporal Characterization of Composition, Microstructure, and Mechanical Properties in Tissue Engineering.

Science.gov (United States)

Deng, Cheri X; Hong, Xiaowei; Stegemann, Jan P

2016-08-01

Ultrasound techniques are increasingly being used to quantitatively characterize both native and engineered tissues. This review provides an overview and selected examples of the main techniques used in these applications. Grayscale imaging has been used to characterize extracellular matrix deposition, and quantitative ultrasound imaging based on the integrated backscatter coefficient has been applied to estimating cell concentrations and matrix morphology in tissue engineering. Spectral analysis has been employed to characterize the concentration and spatial distribution of mineral particles in a construct, as well as to monitor mineral deposition by cells over time. Ultrasound techniques have also been used to measure the mechanical properties of native and engineered tissues. Conventional ultrasound elasticity imaging and acoustic radiation force imaging have been applied to detect regions of altered stiffness within tissues. Sonorheometry and monitoring of steady-state excitation and recovery have been used to characterize viscoelastic properties of tissue using a single transducer to both deform and image the sample. Dual-mode ultrasound elastography uses separate ultrasound transducers to produce a more potent deformation force to microscale characterization of viscoelasticity of hydrogel constructs. These ultrasound-based techniques have high potential to impact the field of tissue engineering as they are further developed and their range of applications expands.
High resolution ultrasound and photoacoustic imaging of single cells

Directory of Open Access Journals (Sweden)

Eric M. Strohm

2016-03-01

Full Text Available High resolution ultrasound and photoacoustic images of stained neutrophils, lymphocytes and monocytes from a blood smear were acquired using a combined acoustic/photoacoustic microscope. Photoacoustic images were created using a pulsed 532 nm laser that was coupled to a single mode fiber to produce output wavelengths from 532 nm to 620 nm via stimulated Raman scattering. The excitation wavelength was selected using optical filters and focused onto the sample using a 20× objective. A 1000 MHz transducer was co-aligned with the laser spot and used for ultrasound and photoacoustic images, enabling micrometer resolution with both modalities. The different cell types could be easily identified due to variations in contrast within the acoustic and photoacoustic images. This technique provides a new way of probing leukocyte structure with potential applications towards detecting cellular abnormalities and diseased cells at the single cell level.
Non-rigid ultrasound image registration using generalized relaxation labeling process

Science.gov (United States)

Lee, Jong-Ha; Seong, Yeong Kyeong; Park, MoonHo; Woo, Kyoung-Gu; Ku, Jeonghun; Park, Hee-Jun

2013-03-01

This research proposes a novel non-rigid registration method for ultrasound images. The most predominant anatomical features in medical images are tissue boundaries, which appear as edges. In ultrasound images, however, other features can be identified as well due to the specular reflections that appear as bright lines superimposed on the ideal edge location. In this work, an image's local phase information (via the frequency domain) is used to find the ideal edge location. The generalized relaxation labeling process is then formulated to align the feature points extracted from the ideal edge location. In this work, the original relaxation labeling method was generalized by taking n compatibility coefficient values to improve non-rigid registration performance. This contextual information combined with a relaxation labeling process is used to search for a correspondence. Then the transformation is calculated by the thin plate spline (TPS) model. These two processes are iterated until the optimal correspondence and transformation are found. We have tested our proposed method and the state-of-the-art algorithms with synthetic data and bladder ultrasound images of in vivo human subjects. Experiments show that the proposed method improves registration performance significantly, as compared to other state-of-the-art non-rigid registration algorithms.
Multimodal system for the planning and guidance of bronchoscopy

Science.gov (United States)

Higgins, William E.; Cheirsilp, Ronnarit; Zang, Xiaonan; Byrnes, Patrick

2015-03-01

Many technical innovations in multimodal radiologic imaging and bronchoscopy have emerged recently in the effort against lung cancer. Modern X-ray computed-tomography (CT) scanners provide three-dimensional (3D) high-resolution chest images, positron emission tomography (PET) scanners give complementary molecular imaging data, and new integrated PET/CT scanners combine the strengths of both modalities. State-of-the-art bronchoscopes permit minimally invasive tissue sampling, with vivid endobronchial video enabling navigation deep into the airway-tree periphery, while complementary endobronchial ultrasound (EBUS) reveals local views of anatomical structures outside the airways. In addition, image-guided intervention (IGI) systems have proven their utility for CT-based planning and guidance of bronchoscopy. Unfortunately, no IGI system exists that integrates all sources effectively through the complete lung-cancer staging work flow. This paper presents a prototype of a computer-based multimodal IGI system that strives to fill this need. The system combines a wide range of automatic and semi-automatic image-processing tools for multimodal data fusion and procedure planning. It also provides a flexible graphical user interface for follow-on guidance of bronchoscopy/EBUS. Human-study results demonstrate the system's potential.

Use of 'non-medical' ultrasound imaging before mid-pregnancy in Copenhagen

DEFF Research Database (Denmark)

Thorup, Tine J; Zingenberg, Helle

2015-01-01

We have investigated prospectively how many pregnant women purchase ultrasound imaging before week 20, why they purchase scans, and which professional skills and certifications women expect the person performing the scan to have. In addition, we wanted to investigate whether the women were aware...... shows that there is a significant demand among pregnant women for commercial ultrasound imaging of their fetus for various reasons. Knowledge of certifications and requirements for legal authorization is, however, sparse....
Pectoralis major tears: anatomy, classification, and diagnosis with ultrasound and MR imaging

Energy Technology Data Exchange (ETDEWEB)

Chiavaras, Mary M. [McMaster University, Department of Radiology, Hamilton, ON (Canada); Jacobson, Jon A. [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Smith, Jay [Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN (United States); Department of Radiology, Mayo Clinic, Rochester, MN (United States); Department of Anatomy, Mayo Clinic, Rochester, MN (United States); Dahm, Diane L. [Department of Orthopaedic Surgery, Mayo Clinic, Rochester, MN (United States)

2014-09-09

Accurate characterization of pectoralis major tears is important to guide management. Imaging evaluation with ultrasound and MR imaging can be difficult given the complex regional anatomy. In addition, recent literature has redefined the anatomy of the distal pectoralis major. The purpose of this study is to review pectoralis major injuries taking into account new anatomic descriptions using ultrasound and MR imaging, including cadaveric dissection, surgically produced pectoralis tears, and clinical pectoralis tendon tear with surgical correlation. (orig.)
Pectoralis major tears: anatomy, classification, and diagnosis with ultrasound and MR imaging

International Nuclear Information System (INIS)

Chiavaras, Mary M.; Jacobson, Jon A.; Smith, Jay; Dahm, Diane L.

2015-01-01

Accurate characterization of pectoralis major tears is important to guide management. Imaging evaluation with ultrasound and MR imaging can be difficult given the complex regional anatomy. In addition, recent literature has redefined the anatomy of the distal pectoralis major. The purpose of this study is to review pectoralis major injuries taking into account new anatomic descriptions using ultrasound and MR imaging, including cadaveric dissection, surgically produced pectoralis tears, and clinical pectoralis tendon tear with surgical correlation. (orig.)
Novel ultrasound-responsive chitosan/perfluorohexane nanodroplets for image-guided smart delivery of an anticancer agent: Curcumin.

Science.gov (United States)

Baghbani, Fatemeh; Chegeni, Mahdieh; Moztarzadeh, Fathollah; Hadian-Ghazvini, Samaneh; Raz, Majid

2017-05-01

Ultrasound-responsive nanodroplets are a class of new emerging smart drug delivery systems which provide image-guided nano-therapy of various diseases, especially cancers. Here, we developed multifunctional smart curcumin-loaded chitosan/perfluorohexane nanodroplets for contrast-ultrasound imaging and on-demand drug delivery. The nanodroplets were synthesized via nanoemulsion process. The optimal formulation with the size of 101.2nm and 77.8% curcumin entrapment was chosen for release study and cytotoxicity evaluation. Sonication at the frequency of 1MHz, 2W/cm 2 for 4min triggered the release of 63.5% of curcumin from optimal formulation (Cur-NDs-2). Ultrasound aided release study indicated that the concentration of perfluorohexane and the degree of acoustic droplet vaporization play important role in ultrasound-active drug release. B-mode ultrasound imaging confirmed strong ultrasound contrast of chitosan nanodroplets even at low concentrations via droplet to bubble transition. Finally, cytotoxicity of the ultrasound-responsive nanodroplets in the presence of ultrasound was evaluated in-vitro on 4T1 human breast cancer cells. Cell growth inhibitory effects of curcumin-loaded nanodroplets significantly increased by ultrasound exposure. According to the obtained results, these ultrasound responsive curcumin-loaded chitosan/perfluorohexane nanodroplets have a great potential for imaged-guided cancer therapy. Copyright © 2016 Elsevier B.V. All rights reserved.
The evaluation of radiologic methods for access guidance in percutaneous nephrolithotomy: a systematic review of the literature.

Science.gov (United States)

Breda, Alberto; Territo, Angelo; Scoffone, Cesare; Seitz, Christian; Knoll, Thomas; Herrmann, Thomas; Brehmer, Mariannhe; Osther, Palle J S; Liatsikos, Evangelos

2017-11-12

Percutaneous nephrolithotomy (PNL) is the treatment of choice for larger and complex renal calculi. First step in performing PNL is to obtain access to the renal cavity using either fluoroscopy or ultrasound (US) guidance or a combination of both. Which guiding method to choose is controversial? A systematic review of the literature was performed comparing image guidance modalities for obtaining access in PNL. Evidence acquisition and synthesis: A PubMed, Scopus and Cochrane search for peer-reviewed studies was performed using the keywords "ultrasound" AND "fluoroscopy" AND "Percutaneous nephrolithotomy". Eligible articles were reviewed according to PRISMA criteria. Two hundred and forty records were identified using the keywords. Of these twelve studies were considered relevant. US guidance seems to be associated with a slightly lower complication rate, which may be related to fewer puncture attempts needed for obtaining access and to better peri-renal organ visualization. On the other hand, US-guidance alone needs the adjunct of fluoroscopy in a significant number of cases for achieving access. Stone free rate (SFR) was comparable between groups. Using US for renal access unequivocally reduces radiation exposure. Current evidence indicates that both fluoroscopy and US guidance may be successfully used for obtaining percutaneous renal access. Combining the image-guiding modalities - US and fluoroscopy - seems to increase outcome in PNL both with regard to success in achieving access and reducing complications. Furthermore, including US in the access strategy of PNL reduces radiation exposure to surgeon and staff as well as patients.
76 FR 43332 - Guidance for Industry and Food and Drug Administration Staff; Class II Special Controls Guidance...

Science.gov (United States)

2011-07-20

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2011-D-0500] Guidance for Industry and Food and Drug Administration Staff; Class II Special Controls Guidance Document: Focused Ultrasound Stimulator System for Aesthetic Use; Availability AGENCY: Food and Drug Administration...
BBB disruption with unfocused ultrasound alone-A paradigm shift

Science.gov (United States)

Kyle, Al

2012-10-01

One paradigm for ultrasound-enabled blood brain barrier disruption uses image guided focused ultrasound and preformed microbubble agents to enable drug delivery to the brain. We propose an alternative approach: unguided, unfocused ultrasound with no adjunctive agent. Compared with the focused approach, the proposed method affects a larger region of the brain, and is aimed at treatment of regional neurological disease including glioblastoma multiforme (GBM). Avoidance of image guidance and focusing reduces cost for equipment and staff training. Avoidance of adjunctive agents also lowers cost and is enabled by a longer exposure time. Since 2004, our group has worked with two animal models, three investigators in four laboratories to safely deliver five compounds, increasing the concentration of large molecule markers in brain tissue two fold or more. Safety and effectiveness data for four studies have been presented at the Ultrasound Industry Association meetings in 2007 and 2010. This paper describes new safety and effectiveness results for a fifth study. We present evidence of delivery of large molecules - including Avastin-to the brains of a large animal model correlated with acoustic pressure, and summarize the advantages and disadvantages of this novel approach.
Plantar fascia segmentation and thickness estimation in ultrasound images.

Science.gov (United States)

Boussouar, Abdelhafid; Meziane, Farid; Crofts, Gillian

2017-03-01

Ultrasound (US) imaging offers significant potential in diagnosis of plantar fascia (PF) injury and monitoring treatment. In particular US imaging has been shown to be reliable in foot and ankle assessment and offers a real-time effective imaging technique that is able to reliably confirm structural changes, such as thickening, and identify changes in the internal echo structure associated with diseased or damaged tissue. Despite the advantages of US imaging, images are difficult to interpret during medical assessment. This is partly due to the size and position of the PF in relation to the adjacent tissues. It is therefore a requirement to devise a system that allows better and easier interpretation of PF ultrasound images during diagnosis. This study proposes an automatic segmentation approach which for the first time extracts ultrasound data to estimate size across three sections of the PF (rearfoot, midfoot and forefoot). This segmentation method uses artificial neural network module (ANN) in order to classify small overlapping patches as belonging or not-belonging to the region of interest (ROI) of the PF tissue. Features ranking and selection techniques were performed as a post-processing step for features extraction to reduce the dimension and number of the extracted features. The trained ANN classifies the image overlapping patches into PF and non-PF tissue, and then it is used to segment the desired PF region. The PF thickness was calculated using two different methods: distance transformation and area-length calculation algorithms. This new approach is capable of accurately segmenting the PF region, differentiating it from surrounding tissues and estimating its thickness. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Aspiration of breast abscess under ultrasound guidance: outcome obtained and factors affecting success.

Science.gov (United States)

Elagili, Faisal; Abdullah, Norlia; Fong, Liew; Pei, Tan

2007-01-01

To assess ultrasonographically (US) guided needle aspiration of breast abscesses as an alternative to surgical incision and drainage. In our prospective study, 30 patients with 31 breast abscesses (one patient had bilateral breast abscess) underwent percutaneous breast abscess drainage under US guidance with local anaesthesia and oral antibiotics between 1 January 2004 and 31 March 2005. These patients consisted of 16 (53.3%) non-lactating and 14 (46.7%) lactating women, with ages ranging from 18 to 68 years (median, 28 years). The racial distribution comprised 26 (86.7%) Malays, three (10%) Chinese and one (3.3%) Indian. All patients had the chief complaint of breast swelling and 25 (83.3%) had breast pain. Clinically, 28 (93.3%) were found to have a palpable mass. Nine (30%) lesions were in the upper outer quadrant of the left breast. US diameters ranged from 1 to 15 cm (median, 4 cm). The pus volumes varied from 1 to 200 mL (median, 14 mL). Fifteen (50%) patients required only a single aspiration, 10 required multiple aspirations and five required incision and drainage. Those patients in whom needle aspiration failed had multiloculated lesions irrespective of abscess volume and size. Needle aspiration with ultrasound guidance is an effective treatment for breast abscess irrespective of abscess volume and size.
Biomedical engineering: A platform for research and innovation in ultrasound

Science.gov (United States)

Holland, Christy K.

2004-05-01

An undergraduate or graduate degree in biomedical engineering prepares students to solve problems at the interface between engineering and medicine. Biomedical engineering encompasses evolving areas such as advanced medical imaging for diagnosis and treatment of disease, tissue engineering for designing and manufacturing biological implants for damaged or diseased tissues and organs, and bioinformatics for determining which genes play a major role in health and disease. Biomedical engineering academic programs produce graduates with the ability to pursue successful careers in the biomedical device industry or to obtain advanced degrees leading to careers in biomedical engineering research, medicine, law or business. Biomedical engineering majors take courses in biology, anatomy, physics, chemistry, engineering, mathematics and medical product design and value life-long learning. Students learn to work effectively in interdisciplinary teams comprised of individuals with diverse social, cultural and technical backgrounds. Biomedical engineering is becoming increasingly important in imaging and image-guided research. Some examples of innovative ultrasound technology under development are ultrasound devices to accelerate the dissolution of blood clots, advanced surgical instruments with ultrasound guidance and ultrasound contrast agents for targeted drug delivery. Biomedical engineering is a great career choice for technically minded individuals who endeavor to work on applied problems that are medically relevant.
High resolution three-dimensional robotic synthetic tracked aperture ultrasound imaging: feasibility study

Science.gov (United States)

Zhang, Haichong K.; Fang, Ting Yun; Finocchi, Rodolfo; Boctor, Emad M.

2017-03-01

Three dimensional (3D) ultrasound imaging is becoming a standard mode for medical ultrasound diagnoses. Conventional 3D ultrasound imaging is mostly scanned either by using a two dimensional matrix array or by motorizing a one dimensional array in the elevation direction. However, the former system is not widely assessable due to its cost, and the latter one has limited resolution and field-of-view in the elevation axis. Here, we propose a 3D ultrasound imaging system based on the synthetic tracked aperture approach, in which a robotic arm is used to provide accurate tracking and motion. While the ultrasound probe is moved by a robotic arm, each probe position is tracked and can be used to reconstruct a wider field-of-view as there are no physical barriers that restrict the elevational scanning. At the same time, synthetic aperture beamforming provides a better resolution in the elevation axis. To synthesize the elevational information, the single focal point is regarded as the virtual element, and forward and backward delay-andsum are applied to the radio-frequency (RF) data collected through the volume. The concept is experimentally validated using a general ultrasound phantom, and the elevational resolution improvement of 2.54 and 2.13 times was measured at the target depths of 20 mm and 110 mm, respectively.
Ultrasound Imaging Methods for Breast Cancer Detection

NARCIS (Netherlands)

Ozmen, N.

2014-01-01

The main focus of this thesis is on modeling acoustic wavefield propagation and implementing imaging algorithms for breast cancer detection using ultrasound. As a starting point, we use an integral equation formulation, which can be used to solve both the forward and inverse problems. This thesis
Lesion Contrast Enhancement in Medical Ultrasound Imaging

DEFF Research Database (Denmark)

Stetson, Paul F.; Sommer, F.G.; Macovski, A.

1997-01-01

Methods for improving the contrast-to-noise ratio (CNR) of low-contrast lesions in medical ultrasound imaging are described. Differences in the frequency spectra and amplitude distributions of the lesion and its surroundings can be used to increase the CNR of the lesion relative to the background...
Image Guidance and Assessment of Radiation Induced Gene Therapy

National Research Council Canada - National Science Library

Pelizzari, Charles

2004-01-01

Image guidance and assessment techniques are being developed for combined radiation/gene therapy, which utilizes a radiation-inducible gene promoter to cause expression of tumor necrosis factor alpha...
Observation of a cavitation cloud in tissue using correlation between ultrafast ultrasound images.

Science.gov (United States)

Prieur, Fabrice; Zorgani, Ali; Catheline, Stefan; Souchon, Rémi; Mestas, Jean-Louis; Lafond, Maxime; Lafon, Cyril

2015-07-01

The local application of ultrasound is known to improve drug intake by tumors. Cavitating bubbles are one of the contributing effects. A setup in which two ultrasound transducers are placed confocally is used to generate cavitation in ex vivo tissue. As the transducers emit a series of short excitation bursts, the evolution of the cavitation activity is monitored using an ultrafast ultrasound imaging system. The frame rate of the system is several thousands of images per second, which provides several tens of images between consecutive excitation bursts. Using the correlation between consecutive images for speckle tracking, a decorrelation of the imaging signal appears due to the creation, fast movement, and dissolution of the bubbles in the cavitation cloud. By analyzing this area of decorrelation, the cavitation cloud can be localized and the spatial extent of the cavitation activity characterized.
Ultrasound imaging of the mouse pancreatic duct using lipid microbubbles

Science.gov (United States)

Banerjee, B.; McKeown, K. R.; Skovan, B.; Ogram, E.; Ingram, P.; Ignatenko, N.; Paine-Murrieta, G.; Witte, R.; Matsunaga, T. O.

2012-03-01

Research requiring the murine pancreatic duct to be imaged is often challenging due to the difficulty in selectively cannulating the pancreatic duct. We have successfully catheterized the pancreatic duct through the common bile duct in severe combined immune deficient (SCID) mice and imaged the pancreatic duct with gas filled lipid microbubbles that increase ultrasound imaging sensitivity due to exquisite scattering at the gas/liquid interface. A SCID mouse was euthanized by CO2, a midline abdominal incision made, the common bile duct cut at its midpoint, a 2 cm, 32 gauge tip catheter was inserted about 1 mm into the duct and tied with suture. The duodenum and pancreas were excised, removed in toto, embedded in agar and an infusion pump was used to instill normal saline or lipid-coated microbubbles (10 million / ml) into the duct. B-mode images before and after infusion of the duct with microbubbles imaged the entire pancreatic duct (~ 1 cm) with high contrast. The microbubbles were cavitated by high mechanical index (HMI) ultrasound for imaging to be repeated. Our technique of catheterization and using lipid microbubbles as a contrast agent may provide an effective, affordable technique of imaging the murine pancreatic duct; cavitation with HMI ultrasound would enable repeated imaging to be performed and clustering of targeted microbubbles to receptors on ductal cells would allow pathology to be localized accurately. This research was supported by the Experimental Mouse Shared Service of the AZ Cancer Center (Grant Number P30CA023074, NIH/NCI and the GI SPORE (NIH/NCI P50 CA95060).
Enhanced Visualization of Fine Needles Under Sonographic Guidance Using a MEMS Actuator

Directory of Open Access Journals (Sweden)

Zhiyuan Shen

2015-01-01

Full Text Available Localization of a needle tip is important for biopsy examinations in clinics. However, the needle tip is sometimes difficult to discern under the guidance of sonography due to its poor visibility. A mini actuator that radiates a low-intensity ultrasound wave was manufactured using micro-electro-mechanical system (MEMS technology. Interference between the radiated and diagnostic ultrasound pulses was observed as bright lines in the B-mode ultrasound image, from which the mini actuator could be recognized with ease. Because the distance between the mini actuator and the needle tip is fixed, the needle tip can be determined despite its inconsistent appearance in the sonography. Both gel phantom and ex vivo tissue evaluation showed that the needle tip can be determined reliably utilizing the acoustic interference pattern.
Parametric imaging of tumor perfusion and neovascular morphology using ultrasound

Science.gov (United States)

Hoyt, Kenneth

2015-03-01

A new image processing strategy is detailed for the simultaneous measurement of tumor perfusion and neovascular morphology parameters from a sequence of dynamic contrast-enhanced ultrasound (DCE-US) images. A technique for locally mapping tumor perfusion parameters using skeletonized neovascular data is also introduced. Simulated images were used to test the neovascular skeletonization technique and variance (error) of relevant parametric estimates. Preliminary DCE-US image datasets were collected in 6 female patients diagnosed with invasive breast cancer and using a Philips iU22 ultrasound system equipped with a L9-3 MHz transducer and Definity contrast agent. Simulation data demonstrates that neovascular morphology parametric estimation is reproducible albeit measurement error can occur at a lower signal-to-noise ratio (SNR). Experimental results indicate the feasibility of our approach to performing both tumor perfusion and neovascular morphology measurements from DCE-US images. Future work will expand on our initial clinical findings and also extent our image processing strategy to 3-dimensional space to allow whole tumor characterization.
Multiparametric Quantitative Ultrasound Imaging in Assessment of Chronic Kidney Disease.

Science.gov (United States)

Gao, Jing; Perlman, Alan; Kalache, Safa; Berman, Nathaniel; Seshan, Surya; Salvatore, Steven; Smith, Lindsey; Wehrli, Natasha; Waldron, Levi; Kodali, Hanish; Chevalier, James

2017-11-01

To evaluate the value of multiparametric quantitative ultrasound imaging in assessing chronic kidney disease (CKD) using kidney biopsy pathologic findings as reference standards. We prospectively measured multiparametric quantitative ultrasound markers with grayscale, spectral Doppler, and acoustic radiation force impulse imaging in 25 patients with CKD before kidney biopsy and 10 healthy volunteers. Based on all pathologic (glomerulosclerosis, interstitial fibrosis/tubular atrophy, arteriosclerosis, and edema) scores, the patients with CKD were classified into mild (no grade 3 and quantitative ultrasound parameters included kidney length, cortical thickness, pixel intensity, parenchymal shear wave velocity, intrarenal artery peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index. We tested the difference in quantitative ultrasound parameters among mild CKD, moderate to severe CKD, and healthy controls using analysis of variance, analyzed correlations of quantitative ultrasound parameters with pathologic scores and the estimated glomerular filtration rate (GFR) using Pearson correlation coefficients, and examined the diagnostic performance of quantitative ultrasound parameters in determining moderate CKD and an estimated GFR of less than 60 mL/min/1.73 m 2 using receiver operating characteristic curve analysis. There were significant differences in cortical thickness, pixel intensity, PSV, and EDV among the 3 groups (all P quantitative ultrasound parameters, the top areas under the receiver operating characteristic curves for PSV and EDV were 0.88 and 0.97, respectively, for determining pathologic moderate to severe CKD, and 0.76 and 0.86 for estimated GFR of less than 60 mL/min/1.73 m 2 . Moderate to good correlations were found for PSV, EDV, and pixel intensity with pathologic scores and estimated GFR. The PSV, EDV, and pixel intensity are valuable in determining moderate to severe CKD. The value of shear wave velocity in
Non-linear Imaging using an Experimental Synthetic Aperture Real Time Ultrasound Scanner

DEFF Research Database (Denmark)

Rasmussen, Joachim; Du, Yigang; Jensen, Jørgen Arendt

2011-01-01

This paper presents the first non-linear B-mode image of a wire phantom using pulse inversion attained via an experimental synthetic aperture real-time ultrasound scanner (SARUS). The purpose of this study is to implement and validate non-linear imaging on SARUS for the further development of new...... non-linear techniques. This study presents non-linear and linear B-mode images attained via SARUS and an existing ultrasound system as well as a Field II simulation. The non-linear image shows an improved spatial resolution and lower full width half max and -20 dB resolution values compared to linear...

Imaging of common bile duct by linear endoscopic ultrasound

Institute of Scientific and Technical Information of China (English)

Malay; Sharma; Amit; Pathak; Abid; Shoukat; Chittapuram; Srinivasan; Rameshbabu; Akash; Ajmera; Zeeshn; Ahamad; Wani; Praveer; Rai

2015-01-01

Imaging of common bile duct(CBD) can be done by many techniques. Endoscopic retrograde cholangiopancreaticography is considered the gold standard for imaging of CBD. A standard technique of imaging of CBD by endoscopic ultrasound(EUS) has not been specifically described. The available descriptions mention different stations of imaging from the stomach and duodenum. The CBD lies closest to duodenum and choice of imaging may be restricted to duodenum for many operators. Generally most operators prefer multi station imaging during EUS and the choice of selecting the initial station varies from operator to operator. Detailed evaluation of CBD is frequently the main focus of imaging during EUS and in such situations multi station imaging with a high-resolution ultrasound scanner may provide useful information. Examination of the CBD is one of the primary indications for doing an EUS and it can be done from five stations:(1) the fundus of stomach;(2) body of stomach;(3) duodenal bulb;(4) descending duodenum; and(5) antrum. Following down the upper 1/3rd of CBD can do imaging of entire CBD from the liver window and following up the lower 1/3rd of CBD can do imaging of entire CBD from the pancreatic window. This article aims at simplifying the techniques of imaging of CBD by linear EUS.
Medical Ultrasound Imaging.

Science.gov (United States)

Hughes, Stephen

2001-01-01

Explains the basic principles of ultrasound using everyday physics. Topics include the generation of ultrasound, basic interactions with material, and the measurement of blood flow using the Doppler effect. (Author/MM)
Enhanced Automated Guidance System for Horizontal Auger Boring Based on Image Processing.

Science.gov (United States)

Wu, Lingling; Wen, Guojun; Wang, Yudan; Huang, Lei; Zhou, Jiang

2018-02-15

Horizontal auger boring (HAB) is a widely used trenchless technology for the high-accuracy installation of gravity or pressure pipelines on line and grade. Differing from other pipeline installations, HAB requires a more precise and automated guidance system for use in a practical project. This paper proposes an economic and enhanced automated optical guidance system, based on optimization research of light-emitting diode (LED) light target and five automated image processing bore-path deviation algorithms. An LED light target was optimized for many qualities, including light color, filter plate color, luminous intensity, and LED layout. The image preprocessing algorithm, direction location algorithm, angle measurement algorithm, deflection detection algorithm, and auto-focus algorithm, compiled in MATLAB, are used to automate image processing for deflection computing and judging. After multiple indoor experiments, this guidance system is applied in a project of hot water pipeline installation, with accuracy controlled within 2 mm in 48-m distance, providing accurate line and grade controls and verifying the feasibility and reliability of the guidance system.
Bas-relief map using texture analysis with application to live enhancement of ultrasound images.

Science.gov (United States)

Du, Huarui; Ma, Rui; Wang, Xiaoying; Zhang, Jue; Fang, Jing

2015-05-01

For ultrasound imaging, speckle is one of the most important factors in the degradation of contrast resolution because it masks meaningful texture and has the potential to interfere with diagnosis. It is expected that researchers would explore appropriate ways to reduce the speckle noise, to find the edges of structures and enhance weak borders between different organs in ultrasound imaging. Inspired by the principle of differential interference contrast microscopy, a "bas-relief map" is proposed that depicts the texture structure of ultrasound images. Based on a bas-relief map, an adaptive bas-relief filter was developed for ultrafast despeckling. Subsequently, an edge map was introduced to enhance the edges of images in real time. The holistic bas-relief map approach has been used experimentally with synthetic phantoms and digital ultrasound B-scan images of liver, kidney and gallbladder. Based on the visual inspection and the performance metrics of the despeckled images, it was found that the bas-relief map approach is capable of effectively reducing the speckle while significantly enhancing contrast and tissue boundaries for ultrasonic images, and its speckle reduction ability is comparable to that of Kuan, Lee and Frost filters. Meanwhile, the proposed technique could preserve more intra-region details compared with the popular speckle reducing anisotropic diffusion technique and more effectively enhance edges. In addition, the adaptive bas-relief filter was much less time consuming than the Kuan, Lee and Frost filter and speckle reducing anisotropic diffusion techniques. The bas-relief map strategy is effective for speckle reduction and live enhancement of ultrasound images, and can provide a valuable tool for clinical diagnosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Enhancing the dynamic range of Ultrasound Imaging Velocimetry using interleaved imaging

NARCIS (Netherlands)

Poelma, C.; Fraser, K.H.

2013-01-01

In recent years, non-invasive velocity field measurement based on correlation of ultrasound images has been introduced as a promising technique for fundamental research into disease processes, as well as a diagnostic tool. A major drawback of the method is the relatively limited dynamic range when
Three-dimensional ultrasound image-guided robotic system for accurate microwave coagulation of malignant liver tumours.

Science.gov (United States)

Xu, Jing; Jia, Zhen-zhong; Song, Zhang-jun; Yang, Xiang-dong; Chen, Ken; Liang, Ping

2010-09-01

The further application of conventional ultrasound (US) image-guided microwave (MW) ablation of liver cancer is often limited by two-dimensional (2D) imaging, inaccurate needle placement and the resulting skill requirement. The three-dimensional (3D) image-guided robotic-assisted system provides an appealing alternative option, enabling the physician to perform consistent, accurate therapy with improved treatment effectiveness. Our robotic system is constructed by integrating an imaging module, a needle-driven robot, a MW thermal field simulation module, and surgical navigation software in a practical and user-friendly manner. The robot executes precise needle placement based on the 3D model reconstructed from freehand-tracked 2D B-scans. A qualitative slice guidance method for fine registration is introduced to reduce the placement error caused by target motion. By incorporating the 3D MW specific absorption rate (SAR) model into the heat transfer equation, the MW thermal field simulation module determines the MW power level and the coagulation time for improved ablation therapy. Two types of wrists are developed for the robot: a 'remote centre of motion' (RCM) wrist and a non-RCM wrist, which is preferred in real applications. The needle placement accuracies were robot with the RCM wrist was improved to 1.6 +/- 1.0 mm when real-time 2D US feedback was used in the artificial-tissue phantom experiment. By using the slice guidance method, the robot with the non-RCM wrist achieved accuracy of 1.8 +/- 0.9 mm in the ex vivo experiment; even target motion was introduced. In the thermal field experiment, a 5.6% relative mean error was observed between the experimental coagulated neurosis volume and the simulation result. The proposed robotic system holds promise to enhance the clinical performance of percutaneous MW ablation of malignant liver tumours. Copyright 2010 John Wiley & Sons, Ltd.
Does the insertion of a gel-based marker at stereotactic breast biopsy allow subsequent wire localizations to be carried out under ultrasound guidance?

International Nuclear Information System (INIS)

McMahon, M.A.; James, J.J.; Cornford, E.J.; Hamilton, L.J.; Burrell, H.C.

2011-01-01

Aim: To investigate whether the insertion of a gel-based marker at the time of stereotactic breast biopsy allows subsequent preoperative localization to be performed under ultrasound guidance. Materials and methods: One hundred consecutive women who underwent either a 10 G stereotactic vacuum-assisted breast biopsy or 14 G stereotactic core biopsy with marker placement, followed by wire localization and surgical excision were identified. All had mammographic abnormalities not initially visible with ultrasound. The method of preoperative localization was recorded and its success judged with reference to the wire position on the post-procedure films relative to the mammographic abnormality and the marker. Histopathology data were reviewed to ensure the lesion had been adequately excised. Results: Eighty-three women (83%) had a successful ultrasound-guided wire localization. Successful ultrasound-guided localization was more likely after stereotactic vacuum biopsy (86%) compared to stereotactic core biopsy (68%), although this did not quite reach statistical significance (p = 0.06). Conclusion: The routine placement of a gel-based marker after stereotactic breast biopsy facilitates preoperative ultrasound-guided localization.
Ultrasound elastography for imaging tendons and muscles

Directory of Open Access Journals (Sweden)

Elena Drakonaki

2012-06-01

Full Text Available Ultrasound elastography is a recently developed ultrasound-based method which allows the qualitative or quantitative evaluation of the mechanical properties of tissue. Strain (compression ultrasound elastography is the commonest technique performed by ap‑ plying mild compression with the hand-held transducer to create real-time strain dis‑ tribution maps, which are color-coded and superimposed on the B-mode images. There is increasing evidence that ultrasound elastography can be used in the investigation of muscle, tendon and soft tissue disease in the clinical practice, as a supplementary tool to conventional ultrasound examination. Based on preliminary data, potential clinical appli‑ cations include early diagnosis, staging, and guiding interventions musculotendinous and neuromuscular disease as well as monitoring disease during rehabilitation. Ultrasound elastography could also be used for research into the biomechanics and pathophysiology of musculotendinous disease. Despite the great interest in the technique, there is still limited evidence in the literature and there are several technical issues which limit the reproducibility of the method, including differences in quantification methods, artefacts, limitations and variation in the application of the technique by different users. This re‑ view presents the published evidence on musculoskeletal applications of strain elastogra‑ phy, discusses the technical issues and future perspectives of this method and emphasizes the need for standardization and further research.
Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging: In Vitro and in Vivo Evaluation

NARCIS (Netherlands)

V. Daeichin (Verya); T. van Rooij (Tom); I. Skachkov (Ilya); B. Ergin (Bulent); P. Specht (Patricia); A.A.P. Lima (Alexandre ); C. Ince (Can); J.G. Bosch (Hans); A.F.W. van der Steen (Ton); N. de Jong (Nico); K. Kooiman (Klazina)

2017-01-01

textabstractAlthough high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited
Imaging of vaporised sub-micron phase change contrast agents with high frame rate ultrasound and optics

Science.gov (United States)

Lin, Shengtao; Zhang, Ge; Jamburidze, Akaki; Chee, Melisse; Hau Leow, Chee; Garbin, Valeria; Tang, Meng-Xing

2018-03-01

Phase-change ultrasound contrast agent (PCCA), or nanodroplet, shows promise as an alternative to the conventional microbubble agent over a wide range of diagnostic applications. Meanwhile, high-frame-rate (HFR) ultrasound imaging with microbubbles enables unprecedented temporal resolution compared to traditional contrast-enhanced ultrasound imaging. The combination of HFR ultrasound imaging and PCCAs can offer the opportunity to observe and better understand PCCA behaviour after vaporisation captures the fast phenomenon at a high temporal resolution. In this study, we utilised HFR ultrasound at frame rates in the kilohertz range (5-20 kHz) to image native and size-selected PCCA populations immediately after vaporisation in vitro within clinical acoustic parameters. The size-selected PCCAs through filtration are shown to preserve a sub-micron-sized (mean diameter 1 µm) that originate from native PCCA emulsion. The results demonstrate imaging signals with different amplitudes and temporal features compared to that of microbubbles. Compared with the microbubbles, both the B-mode and pulse-inversion (PI) signals from the vaporised PCCA populations were reduced significantly in the first tens of milliseconds, while only the B-mode signals from the PCCAs were recovered during the next 400 ms, suggesting significant changes to the size distribution of the PCCAs after vaporisation. It is also shown that such recovery in signal over time is not evident when using size-selective PCCAs. Furthermore, it was found that signals from the vaporised PCCA populations are affected by the amplitude and frame rate of the HFR ultrasound imaging. Using high-speed optical camera observation (30 kHz), we observed a change in particle size in the vaporised PCCA populations exposed to the HFR ultrasound imaging pulses. These findings can further the understanding of PCCA behaviour under HFR ultrasound imaging.
High Resolution Depth-Resolved Imaging From Multi-Focal Images for Medical Ultrasound

DEFF Research Database (Denmark)

Diamantis, Konstantinos; Dalgarno, Paul A.; Greenaway, Alan H.

2015-01-01

An ultrasound imaging technique providing subdiffraction limit axial resolution for point sources is proposed. It is based on simultaneously acquired multi-focal images of the same object, and on the image metric of sharpness. The sharpness is extracted by image data and presents higher values...... calibration curves combined with the use of a maximum-likelihood algorithm is then able to estimate, with high precision, the depth location of any emitter fron each single image. Estimated values are compared with the ground truth demonstrating that an accuracy of 28.6 µm (0.13λ) is achieved for a 4 mm depth...
Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging : In Vitro and in Vivo Evaluation

NARCIS (Netherlands)

Daeichin, Verya; van Rooij, Tom; Skachkov, Ilya; Ergin, Bulent; Specht, Patricia A.C.; Lima, Alexandre; Ince, Can; Bosch, Johan G.; van der Steen, A.F.W.; de Jong, N.; Kooiman, Klazina

2017-01-01

Although high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited commercially
Microbubble Composition and Preparation for High-Frequency Contrast-Enhanced Ultrasound Imaging: In Vitro and In Vivo Evaluation

NARCIS (Netherlands)

Daeichin, Verya; van Rooij, Tom; Skachkov, Ilya; Ergin, Bulent; Specht, Patricia A. C.; Lima, Alexandre; Ince, Can; Bosch, Johan G.; van der Steen, Antonius F. W.; de Jong, Nico; Kooiman, Klazina

2017-01-01

Although high-frequency ultrasound imaging is gaining attention in various applications, hardly any ultrasound contrast agents (UCAs) dedicated to such frequencies (>15 MHz) are available for contrast-enhanced ultrasound (CEUS) imaging. Moreover, the composition of the limited commercially available
Techniques for Interventional MRI Guidance in Closed-Bore Systems.

Science.gov (United States)

Busse, Harald; Kahn, Thomas; Moche, Michael

2018-02-01

Efficient image guidance is the basis for minimally invasive interventions. In comparison with X-ray, computed tomography (CT), or ultrasound imaging, magnetic resonance imaging (MRI) provides the best soft tissue contrast without ionizing radiation and is therefore predestined for procedural control. But MRI is also characterized by spatial constraints, electromagnetic interactions, long imaging times, and resulting workflow issues. Although many technical requirements have been met over the years-most notably magnetic resonance (MR) compatibility of tools, interventional pulse sequences, and powerful processing hardware and software-there is still a large variety of stand-alone devices and systems for specific procedures only.Stereotactic guidance with the table outside the magnet is common and relies on proper registration of the guiding grids or manipulators to the MR images. Instrument tracking, often by optical sensing, can be added to provide the physicians with proper eye-hand coordination during their navigated approach. Only in very short wide-bore systems, needles can be advanced at the extended arm under near real-time imaging. In standard magnets, control and workflow may be improved by remote operation using robotic or manual driving elements.This work highlights a number of devices and techniques for different interventional settings with a focus on percutaneous, interstitial procedures in different organ regions. The goal is to identify technical and procedural elements that might be relevant for interventional guidance in a broader context, independent of the clinical application given here. Key challenges remain the seamless integration into the interventional workflow, safe clinical translation, and proper cost effectiveness.
Volumetric image-guidance: Does routine usage prompt adaptive re-planning? An institutional review

International Nuclear Information System (INIS)

Tanyi, James A.; Fuss, Martin H.

2008-01-01

Purpose. To investigate how the use of volumetric image-guidance using an on-board cone-beam computed tomography (CBCT) system impacts on the frequency of adaptive re-planning. Material and methods. Treatment courses of 146 patients who have undergone a course of external beam radiation therapy (EBRT) using volumetric CBCT image-guidance were analyzed. Target locations included the brain, head and neck, chest, abdomen, as well as prostate and non-prostate pelvis. The majority of patients (57.5%) were treated with hypo-fractionated treatment regimens (three to 15 fraction courses). The frequency of image-guidance ranged from daily (87.7%) to weekly or twice weekly. The underlying medical necessity for adaptive re-planning as well as frequency and consequences of plan adaptation to dose-volume parameters was assessed. Results. Radiation plans of 34 patients (23.3%) were adapted at least once (up to six time) during their course of EBRT as a result of image-guidance CBCT review. Most common causes for adaptive planning were: tumor change (mostly shrinkage: 10 patients; four patients more than one re-plan), change in abdominal girth (systematic change in hollow organ filling; n=7, two patients more than one re-plan), weight loss (n=5), and systematic target setup deviation from simulation (n=5). Adaptive re-plan was required mostly for conventionally fractionated courses; only 5 patient plans undergoing hypo-fractionated treatment were adjusted. In over 91% of adapted plans, the dose-volume parameters did deviate from the prescribed plan parameters by more than 5% for at least 10% of the target volume, or organs-at-risk in close proximity to the target volume. Discussion. Routine use of volumetric image-guidance has in our practice increased the demand for adaptive re-planning. Volumetric CBCT image-guidance provides sufficient imaging information to reliably predict the need for dose adjustment. In the vast majority of cases evaluated, the initial and adapted dose
General Ultrasound Imaging

Medline Plus

Full Text Available ... may produce minimal discomfort. If a Doppler ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured. Most ultrasound examinations ...
Spatial filters for focusing ultrasound images

DEFF Research Database (Denmark)

Jensen, Jørgen Arendt; Gori, Paola

2001-01-01

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

Science.gov (United States)

Rehmani, Razia; Endo, Yoshimi; Bauman, Phillip; Hamilton, William; Potter, Hollis; Adler, Ronald

2015-10-01

Altered biomechanics from repetitive microtrauma, such as long practice hours in en pointe (tip of the toes) or demi pointe (balls of the feet) predispose ballet dancers to a multitude of musculoskeletal pathologies particularly in the lower extremities. Both ultrasound and magnetic resonance imaging (MRI) are radiation-sparing modalities which can be used to confidently evaluate these injuries, with ultrasound (US) offering the added utility of therapeutic intervention at the same time in experienced hands. The purposes of this paper were: (1) to illustrate the US and MRI features of lower extremity injury patterns in ballet dancers, focusing on pathologies commonly encountered at a single orthopedic hospital; (2) to present complementary roles of both ultrasound and MRI in the evaluation of these injuries whenever possible; (3) to review and present our institutional approach towards therapeutic ultrasound-guided interventions by presenting explicit cases. Online searches were performed using the search criteria of "ballet biomechanics" and "ballet injuries." The results were then further narrowed down by limiting articles published in the past 15 years, modality (US and MRI), anatomical region (foot and ankle, hip and knee) and to major radiology, orthopedics, and sports medicine journals. Performing ballet poses major stress to lower extremities and predisposes dancer to several musculoskeletal injuries. These can be adequately evaluated by both US and MRI. US is useful for evaluating superficial structures such as soft tissues, tendons, and ligaments, particularly in the foot and ankle. MRI provides superior resolution of deeper structures such as joints, bone marrow, and cartilage. In addition, US can be used as a therapeutic tool for providing quick symptomatic improvement in these athletes for who "time is money". Performing ballet may cause major stress to the lower extremities, predominantly affecting the foot and ankle, followed by the knee and hip. US
Percutaneous Nephrolithotomy under Ultrasound Guidance in Patients with Renal Calculi and Autosomal Dominant Polycystic Kidney Disease: A Report of 11 Cases

Directory of Open Access Journals (Sweden)

Xiao Wang

2017-01-01

Full Text Available Nephrolithiasis accelerates the renal failure in the patients with ADPKD. In order to evaluate the role of percutaneous nephrolithotomy in management of calculus in these patients, 11 patients with autosomal dominant polycystic kidney disease and renal stones were included in the study. Two patients had bilateral renal stones. All patients were treated by percutaneous nephrolithotomy under ultrasound guidance. 13 percutaneous nephrolithotomy procedures were performed in 1 stage by the urology team under ultrasound guidance. 5 people received second operation with flexible nephroscopy in lateral position. The success rate and morbidity and mortality of the technique and hospital stay were recorded. Results. The puncture procedure was fully successful in all cases. The renal function improved in these patients. 5 patients had moderate fever after the surgery. 5 patients received flexible nephroscopy to take out the residual calculi. 2 persons had ESWL therapy after the surgery. Conclusion. PCNL is an ideal, safe, and effective method to remove the stones from those patients with no definite increase in the risk of complication. The outcome and stone-free rate are satisfactory comparable to the PCNL in the patients without ADPKD.
Twofold processing for denoising ultrasound medical images.

Science.gov (United States)

Kishore, P V V; Kumar, K V V; Kumar, D Anil; Prasad, M V D; Goutham, E N D; Rahul, R; Krishna, C B S Vamsi; Sandeep, Y

2015-01-01

Ultrasound medical (US) imaging non-invasively pictures inside of a human body for disease diagnostics. Speckle noise attacks ultrasound images degrading their visual quality. A twofold processing algorithm is proposed in this work to reduce this multiplicative speckle noise. First fold used block based thresholding, both hard (BHT) and soft (BST), on pixels in wavelet domain with 8, 16, 32 and 64 non-overlapping block sizes. This first fold process is a better denoising method for reducing speckle and also inducing object of interest blurring. The second fold process initiates to restore object boundaries and texture with adaptive wavelet fusion. The degraded object restoration in block thresholded US image is carried through wavelet coefficient fusion of object in original US mage and block thresholded US image. Fusion rules and wavelet decomposition levels are made adaptive for each block using gradient histograms with normalized differential mean (NDF) to introduce highest level of contrast between the denoised pixels and the object pixels in the resultant image. Thus the proposed twofold methods are named as adaptive NDF block fusion with hard and soft thresholding (ANBF-HT and ANBF-ST). The results indicate visual quality improvement to an interesting level with the proposed twofold processing, where the first fold removes noise and second fold restores object properties. Peak signal to noise ratio (PSNR), normalized cross correlation coefficient (NCC), edge strength (ES), image quality Index (IQI) and structural similarity index (SSIM), measure the quantitative quality of the twofold processing technique. Validation of the proposed method is done by comparing with anisotropic diffusion (AD), total variational filtering (TVF) and empirical mode decomposition (EMD) for enhancement of US images. The US images are provided by AMMA hospital radiology labs at Vijayawada, India.

General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... legs, neck and/or brain (in infants and children) or within various body organs such as the ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... top of page What are the benefits vs. risks? Benefits Most ultrasound scanning is noninvasive (no needles ... procedures such as needle biopsies and fluid aspiration. Risks For standard diagnostic ultrasound , there are no known ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... color picture. It can also convert blood flow information into a distinctive sound that can be heard ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... care physician, or to the physician or other healthcare provider who requested the exam. Usually, the referring ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... size, shape and consistency (whether the object is solid or filled with fluid). In medicine, ultrasound is ... ultrasound, measures the direction and speed of blood cells as they move through vessels. The movement of ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... procedure? Ultrasound examinations can help to diagnose a variety of conditions and to assess organ damage following ... the Ultrasound-Guided Breast Biopsy page . diagnose a variety of heart conditions, including valve problems and congestive ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... in infections With knowledge about the speed and volume of blood flow gained from a Doppler ultrasound ... the body while other areas, especially air-filled lungs, are poorly suited for ultrasound. top of page ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... sonography is performed using the same transducer. Rarely, young children may need to be sedated in order ...
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... American College of Radiology (ACR) and the Radiological Society of North America (RSNA), comprising physicians with expertise ...
Ultrasound imaging accurately identifies the intercostobrachial nerve

Directory of Open Access Journals (Sweden)

Ahmed K. Thallaj

2015-10-01

Full Text Available Objectives: To test the hypothesis that identification and blockade of the intercostobrachial nerve (ICBN can be achieved under ultrasound (US guidance using a small volume of local anesthetic. Methods: Twenty-eight adult male volunteers were examined at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia from November 2012 to September 2013. Intercostobrachial nerve blockade was performed using one ml of 2% lidocaine under US guidance. A sensory map of the blocked area was developed relative to the medial aspect of the humeral head. Results: The ICBN appears as a hyper-echoic structure. The nerve diameter was 2.3±0.28 mm, and the depth was 9±0.28 mm. The measurements of the sensory-blocked area relative to the medial aspect of the humeral head were as follows: 6.3±1.6 cm anteriorly; 6.2±2.9 cm posteriorly; 9.4±2.9 cm proximally; and 9.2±4.4 cm distally. Intercostobrachial nerve blockade using one ml of local anesthetic was successful in all cases. Conclusion: The present study described the sonographic anatomical details of the ICBN and its sensory distribution to successfully perform selective US-guided ICBN blockade.
Imaging of implant needles for real-time HDR-brachytherapy prostate treatment using biplane ultrasound transducers.

Science.gov (United States)

Siebert, Frank-André; Hirt, Markus; Niehoff, Peter; Kovács, György

2009-08-01

Ultrasound imaging is becoming increasingly important in prostate brachytherapy. In high-dose-rate (HDR) real-time planning procedures the definition of the implant needles is often performed by transrectal ultrasound. This article describes absolute measurements of the visibility and accuracy of manual detection of implant needle tips and compares measurement results of different biplane ultrasound systems in transversal and longitudinal (i.e., sagittal) ultrasound modes. To obtain a fixed coordinate system and stable conditions the measurements were carried out in a water tank using a dedicated marker system. Needles were manually placed in the phantom until the observer decided by the real-time ultrasound image that the zero position was reached. A comparison of three different ultrasound systems yielded an offset between 0.8 and 3.1 mm for manual detection of the needle tip in ultrasound images by one observer. The direction of the offset was discovered to be in the proximal direction, i.e., the actual needle position was located more distally compared to the ultrasound-based definition. In the second part of the study, the ultrasound anisotropy of trocar implant needles is reported. It was shown that the integrated optical density in a region of interest around the needle tip changes with needle rotation. Three peaks were observed with a phase angle of 120 degrees. Peaks appear not only in transversal but also in longitudinal ultrasound images, with a phase shift of 60 degrees. The third section of this study shows results of observer dependent influences on needle tip detection in sagittal ultrasound images considering needle rotation. These experiments were carried out using the marker system in a water tank. The needle tip was placed exactly at the position z=0 mm. It was found that different users tend to differently interpret the same ultrasound images. The needle tip was manually detected five times in the ultrasound images by three experienced observers
General Ultrasound Imaging

Medline Plus

Full Text Available ... flat sections of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats ... at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2018 ...
MO-DE-202-00: Image-Guided Interventions: Advances in Intraoperative Imaging, Guidance, and An Emerging Role for Medical Physics in Surgery

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-06-15

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

DEFF Research Database (Denmark)

Tan, York Kiat; Østergaard, Mikkel; Bird, Paul

2014-01-01

Over the past decade there have been significant advances in the field of musculoskeletal imaging, especially in the application of ultrasound (US) and magnetic resonance imaging (MRI) to the management of rheumatoid arthritis (RA). Both modalities offer significant advantages over the previous...
GPU-accelerated Kernel Regression Reconstruction for Freehand 3D Ultrasound Imaging.

Science.gov (United States)

Wen, Tiexiang; Li, Ling; Zhu, Qingsong; Qin, Wenjian; Gu, Jia; Yang, Feng; Xie, Yaoqin

2017-07-01

Volume reconstruction method plays an important role in improving reconstructed volumetric image quality for freehand three-dimensional (3D) ultrasound imaging. By utilizing the capability of programmable graphics processing unit (GPU), we can achieve a real-time incremental volume reconstruction at a speed of 25-50 frames per second (fps). After incremental reconstruction and visualization, hole-filling is performed on GPU to fill remaining empty voxels. However, traditional pixel nearest neighbor-based hole-filling fails to reconstruct volume with high image quality. On the contrary, the kernel regression provides an accurate volume reconstruction method for 3D ultrasound imaging but with the cost of heavy computational complexity. In this paper, a GPU-based fast kernel regression method is proposed for high-quality volume after the incremental reconstruction of freehand ultrasound. The experimental results show that improved image quality for speckle reduction and details preservation can be obtained with the parameter setting of kernel window size of [Formula: see text] and kernel bandwidth of 1.0. The computational performance of the proposed GPU-based method can be over 200 times faster than that on central processing unit (CPU), and the volume with size of 50 million voxels in our experiment can be reconstructed within 10 seconds.
Quantitative ultrasound imaging detects degenerative changes in articular cartilage surface and subchondral bone

International Nuclear Information System (INIS)

Saarakkala, Simo; Laasanen, Mikko S; Jurvelin, Jukka S; Toeyraes, Juha

2006-01-01

Previous studies have suggested that quantitative ultrasound imaging could sensitively diagnose degeneration of the articular surface and changes in the subchondral bone during the development of osteoarthrosis (OA). We have recently introduced a new parameter, ultrasound roughness index (URI), for the quantification of cartilage surface roughness, and successfully tested it with normal and experimentally degraded articular surfaces. In this in vitro study, the applicability of URI was tested in bovine cartilage samples with spontaneously developed tissue degeneration. Simultaneously, we studied the sensitivity of quantitative ultrasound imaging to detect degenerative changes in the cartilage-bone interface. For reference, histological degenerative grade of the cartilage samples was determined. Mechanical reference measurements were also conducted. Cartilage surface roughness (URI) was significantly (p < 0.05) higher in histologically degenerated samples with inferior mechanical properties. Ultrasound reflection at the cartilage-bone interface was also significantly (p < 0.05) increased in degenerated samples. Furthermore, it was quantitatively confirmed that ultrasound attenuation in the overlying cartilage significantly affects the measured ultrasound reflection values from the cartilage-bone interface. To conclude, the combined ultrasound measurement of the cartilage surface roughness and ultrasound reflection at the cartilage-bone interface complement each other, and may together enable more sensitive and quantitative diagnosis of early OA or follow up after surgical cartilage repair
Iterative Minimum Variance Beamformer with Low Complexity for Medical Ultrasound Imaging.

Science.gov (United States)

Deylami, Ali Mohades; Asl, Babak Mohammadzadeh

2018-06-04

Minimum variance beamformer (MVB) improves the resolution and contrast of medical ultrasound images compared with delay and sum (DAS) beamformer. The weight vector of this beamformer should be calculated for each imaging point independently, with a cost of increasing computational complexity. The large number of necessary calculations limits this beamformer to application in real-time systems. A beamformer is proposed based on the MVB with lower computational complexity while preserving its advantages. This beamformer avoids matrix inversion, which is the most complex part of the MVB, by solving the optimization problem iteratively. The received signals from two imaging points close together do not vary much in medical ultrasound imaging. Therefore, using the previously optimized weight vector for one point as initial weight vector for the new neighboring point can improve the convergence speed and decrease the computational complexity. The proposed method was applied on several data sets, and it has been shown that the method can regenerate the results obtained by the MVB while the order of complexity is decreased from O(L 3 ) to O(L 2 ). Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.
Sparse dictionary for synthetic transmit aperture medical ultrasound imaging.

Science.gov (United States)

Wang, Ping; Jiang, Jin-Yang; Li, Na; Luo, Han-Wu; Li, Fang; Cui, Shi-Gang

2017-07-01

It is possible to recover a signal below the Nyquist sampling limit using a compressive sensing technique in ultrasound imaging. However, the reconstruction enabled by common sparse transform approaches does not achieve satisfactory results. Considering the ultrasound echo signal's features of attenuation, repetition, and superposition, a sparse dictionary with the emission pulse signal is proposed. Sparse coefficients in the proposed dictionary have high sparsity. Images reconstructed with this dictionary were compared with those obtained with the three other common transforms, namely, discrete Fourier transform, discrete cosine transform, and discrete wavelet transform. The performance of the proposed dictionary was analyzed via a simulation and experimental data. The mean absolute error (MAE) was used to quantify the quality of the reconstructions. Experimental results indicate that the MAE associated with the proposed dictionary was always the smallest, the reconstruction time required was the shortest, and the lateral resolution and contrast of the reconstructed images were also the closest to the original images. The proposed sparse dictionary performed better than the other three sparse transforms. With the same sampling rate, the proposed dictionary achieved excellent reconstruction quality.
Development of an Anthropomorphic Breast Phantom for Combined PET, B-Mode Ultrasound and Elastographic Imaging

OpenAIRE

Dang, J; Lecoq, P; Tavernier, S; Lasaygues, P; Mensah, S; Zhang, D C; Auffray, E; Frisch, B; Varela, J; Wan, M X; Felix, N

2011-01-01

International audience; Combining the advantages of different imaging modalities leads to improved clinical results. For example, ultrasound provides good real-time structural information without any radiation and PET provides sensitive functional information. For the ongoing ClearPEM-Sonic project combining ultrasound and PET for breast imaging, we developed a dual-modality PET/Ultrasound (US) phantom. The phantom reproduces the acoustic and elastic properties of human breast tissue and allo...

Ultrasound introscopic image quantitative characteristics for medical diagnosis

Science.gov (United States)

Novoselets, Mikhail K.; Sarkisov, Sergey S.; Gridko, Alexander N.; Tcheban, Anatoliy K.

1993-09-01

The results on computer aided extraction of quantitative characteristics (QC) of ultrasound introscopic images for medical diagnosis are presented. Thyroid gland (TG) images of Chernobil Accident sufferers are considered. It is shown that TG diseases can be associated with some values of selected QCs of random echo distribution in the image. The possibility of these QCs usage for TG diseases recognition in accordance with calculated values is analyzed. The role of speckle noise elimination in the solution of the problem on TG diagnosis is considered too.
Cavitation and contrast: the use of bubbles in ultrasound imaging and therapy.

Science.gov (United States)

Stride, E P; Coussios, C C

2010-01-01

Microbubbles and cavitation are playing an increasingly significant role in both diagnostic and therapeutic applications of ultrasound. Microbubble ultrasound contrast agents have been in clinical use now for more than two decades, stimulating the development of a range of new contrast-specific imaging techniques which offer substantial benefits in echocardiography, microcirculatory imaging, and more recently, quantitative and molecular imaging. In drug delivery and gene therapy, microbubbles are being investigated/developed as vehicles which can be loaded with the required therapeutic agent, traced to the target site using diagnostic ultrasound, and then destroyed with ultrasound of higher intensity energy burst to release the material locally, thus avoiding side effects associated with systemic administration, e.g. of toxic chemotherapy. It has moreover been shown that the motion of the microbubbles increases the permeability of both individual cell membranes and the endothelium, thus enhancing therapeutic uptake, and can locally increase the activity of drugs by enhancing their transport across biologically inaccessible interfaces such as blood clots or solid tumours. In high-intensity focused ultrasound (HIFU) surgery and lithotripsy, controlled cavitation is being investigated as a means of increasing the speed and efficacy of the treatment. The aim of this paper is both to describe the key features of the physical behaviour of acoustically driven bubbles which underlie their effectiveness in biomedical applications and to review the current state of the art.
Verification and compensation of respiratory motion using an ultrasound imaging system

International Nuclear Information System (INIS)

Chuang, Ho-Chiao; Hsu, Hsiao-Yu; Chiu, Wei-Hung; Tien, Der-Chi; Wu, Ren-Hong; Hsu, Chung-Hsien

2015-01-01

Purpose: The purpose of this study was to determine if it is feasible to use ultrasound imaging as an aid for moving the treatment couch during diagnosis and treatment procedures associated with radiation therapy, in order to offset organ displacement caused by respiratory motion. A noninvasive ultrasound system was used to replace the C-arm device during diagnosis and treatment with the aims of reducing the x-ray radiation dose on the human body while simultaneously being able to monitor organ displacements. Methods: This study used a proposed respiratory compensating system combined with an ultrasound imaging system to monitor the compensation effect of respiratory motion. The accuracy of the compensation effect was verified by fluoroscopy, which means that fluoroscopy could be replaced so as to reduce unnecessary radiation dose on patients. A respiratory simulation system was used to simulate the respiratory motion of the human abdomen and a strain gauge (respiratory signal acquisition device) was used to capture the simulated respiratory signals. The target displacements could be detected by an ultrasound probe and used as a reference for adjusting the gain value of the respiratory signal used by the respiratory compensating system. This ensured that the amplitude of the respiratory compensation signal was a faithful representation of the target displacement. Results: The results show that performing respiratory compensation with the assistance of the ultrasound images reduced the compensation error of the respiratory compensating system to 0.81–2.92 mm, both for sine-wave input signals with amplitudes of 5, 10, and 15 mm, and human respiratory signals; this represented compensation of the respiratory motion by up to 92.48%. In addition, the respiratory signals of 10 patients were captured in clinical trials, while their diaphragm displacements were observed simultaneously using ultrasound. Using the respiratory compensating system to offset, the diaphragm
A real-time remote video streaming platform for ultrasound imaging.

Science.gov (United States)

Ahmadi, Mehdi; Gross, Warren J; Kadoury, Samuel

2016-08-01

Ultrasound is a viable imaging technology in remote and resources-limited areas. Ultrasonography is a user-dependent skill which depends on a high degree of training and hands-on experience. However, there is a limited number of skillful sonographers located in remote areas. In this work, we aim to develop a real-time video streaming platform which allows specialist physicians to remotely monitor ultrasound exams. To this end, an ultrasound stream is captured and transmitted through a wireless network into remote computers, smart-phones and tablets. In addition, the system is equipped with a camera to track the position of the ultrasound probe. The main advantage of our work is using an open source platform for video streaming which gives us more control over streaming parameters than the available commercial products. The transmission delays of the system are evaluated for several ultrasound video resolutions and the results show that ultrasound videos close to the high-definition (HD) resolution can be received and displayed on an Android tablet with the delay of 0.5 seconds which is acceptable for accurate real-time diagnosis.
Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

Science.gov (United States)

Renaud, G.; Bosch, J. G.; ten Kate, G. L.; Shamdasani, V.; Entrekin, R.; de Jong, N.; van der Steen, A. F. W.

2012-11-01

Most techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic waves propagating in opposite directions (counter-propagation). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear propagation artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-propagating wave interaction creates no pseudoenhancement behind the cavity in the contrast image.
Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

International Nuclear Information System (INIS)

Renaud, G; Bosch, J G; Ten Kate, G L; De Jong, N; Van der Steen, A F W; Shamdasani, V; Entrekin, R

2012-01-01

Most techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic waves propagating in opposite directions (counter-propagation). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear propagation artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-propagating wave interaction creates no pseudoenhancement behind the cavity in the contrast image. (fast track communication)
A successful model to learn and implement ultrasound-guided venous catheterization in apheresis.

Science.gov (United States)

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

2017-12-01

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

Science.gov (United States)

Bulman, J B; Ganezer, K S; Halcrow, P W; Neeson, Ian

2012-06-01

The purpose of this paper was to take the first steps toward applying noncontact ultrasound (NCU) to the tasks of monitoring osteoporosis and quantitative ultrasound imaging (QUS) of cortical bone. The authors also focused on the advantages of NCU, such as its lack of reliance on a technologist to apply transducers and a layer of acoustical coupling gel, the ability of the transducers to operate autonomously as specified by preprogrammed software, and the likely reduction in statistical and systematic errors associated with the variability in the pressure applied by the clinician to the transmitting transducer that NCU might provide. The authors also undertook this study in order to find additional applications of NCU beyond its past limited usage in assessing the severity of third degree burns. A noncontact ultrasound imaging system using a pair of specially designed broadband, 1.5 MHz noncontact piezoelectric transducers and cortical bone phantoms, were used to determine bone mineral density (BMD), speed of sound (SOS), integrated response (IR), and ultrasonic transmittance. Air gaps of greater than 3 cm, two transmission and two reflection paths, and a digital signal processor were also used in the collection of data from phantoms of nominal mass densities that varied from 1.17 to 2.25 g/cm(3) and in bone mineral density from 0 to 1.7 g/cm(3). Good correlations between known BMD and measured SOS, IR, and transmittance were obtained for all 17 phantoms, and methods for quantifying and minimizing sources of systematic errors were outlined. The BMD of the phantom sets extended through most of the in vivo range found in cortical bone. A total of 16-20 repeated measurements of the SOS, thickness, and IR for the phantom set that were conducted over a period of several months showed a small variation in the range of measurements of ±1%-2%. These NCU data were shown to be in agreement with similar results using contact ultrasound to be within 1%-2%. Transmittance
Speckle Reduction on Ultrasound Liver Images Based on a Sparse Representation over a Learned Dictionary

Directory of Open Access Journals (Sweden)

Mohamed Yaseen Jabarulla

2018-05-01

Full Text Available Ultrasound images are corrupted with multiplicative noise known as speckle, which reduces the effectiveness of image processing and hampers interpretation. This paper proposes a multiplicative speckle suppression technique for ultrasound liver images, based on a new signal reconstruction model known as sparse representation (SR over dictionary learning. In the proposed technique, the non-uniform multiplicative signal is first converted into additive noise using an enhanced homomorphic filter. This is followed by pixel-based total variation (TV regularization and patch-based SR over a dictionary trained using K-singular value decomposition (KSVD. Finally, the split Bregman algorithm is used to solve the optimization problem and estimate the de-speckled image. The simulations performed on both synthetic and clinical ultrasound images for speckle reduction, the proposed technique achieved peak signal-to-noise ratios of 35.537 dB for the dictionary trained on noisy image patches and 35.033 dB for the dictionary trained using a set of reference ultrasound image patches. Further, the evaluation results show that the proposed method performs better than other state-of-the-art denoising algorithms in terms of both peak signal-to-noise ratio and subjective visual quality assessment.
First use of a truly-hybrid x-ray/MR imaging system for guidance of brain biopsy

International Nuclear Information System (INIS)

Fahrig, R.; Daniel, B.L.; Butts, K.; Pelc, N.J.; Heit, G.; Wen, Z.

2003-01-01

The use of a new hybrid imaging system for guidance of a brain biopsy is described. The system combines the strengths of MRI (soft-tissue contrast, arbitrary plane selection) with those of x-ray fluoroscopy (high-resolution real-time projection images, clear portrayal of bony structures) and allows switching between the imaging modalities without moving the patient. The biopsy was carried out using x-ray guidance for direction of the needle through the foramen ovale and MR guidance to target the soft-tissue lesion. Appropriate samples were acquired. The system could be particularly effective for guidance of those cases where motion, swelling, resection and other intra-operative anatomical changes cannot be accounted for using traditional stereotactic-based imaging approaches. (author)
Ultrasound -- Pelvis

Medline Plus

Full Text Available ... Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored by Please ...
Echocardiographic and Fluoroscopic Fusion Imaging for Procedural Guidance: An Overview and Early Clinical Experience.

Science.gov (United States)

Thaden, Jeremy J; Sanon, Saurabh; Geske, Jeffrey B; Eleid, Mackram F; Nijhof, Niels; Malouf, Joseph F; Rihal, Charanjit S; Bruce, Charles J

2016-06-01

There has been significant growth in the volume and complexity of percutaneous structural heart procedures in the past decade. Increasing procedural complexity and accompanying reliance on multimodality imaging have fueled the development of fusion imaging to facilitate procedural guidance. The first clinically available system capable of echocardiographic and fluoroscopic fusion for real-time guidance of structural heart procedures was approved by the US Food and Drug Administration in 2012. Echocardiographic-fluoroscopic fusion imaging combines the precise catheter and device visualization of fluoroscopy with the soft tissue anatomy and color flow Doppler information afforded by echocardiography in a single image. This allows the interventionalist to perform precise catheter manipulations under fluoroscopy guidance while visualizing critical tissue anatomy provided by echocardiography. However, there are few data available addressing this technology's strengths and limitations in routine clinical practice. The authors provide a critical review of currently available echocardiographic-fluoroscopic fusion imaging for guidance of structural heart interventions to highlight its strengths, limitations, and potential clinical applications and to guide further research into value of this emerging technology. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.
Feasibility of contrast-enhanced ultrasound-guided biopsy of sentinel lymph nodes in dogs.

Science.gov (United States)

Gelb, Hylton R; Freeman, Lynetta J; Rohleder, Jacob J; Snyder, Paul W

2010-01-01

Our goal was to develop and validate a technique to identify the sentinel lymph nodes of the mammary glands of healthy dogs with contrast-enhanced ultrasound, and evaluate the feasibility of obtaining representative samples of a sentinel lymph node under ultrasound guidance using a new biopsy device. Three healthy intact female adult hounds were anesthetized and each received an injection of octafluoropropane-filled lipid microspheres and a separate subcutaneous injection of methylene blue dye around a mammary gland. Ultrasound was then used to follow the contrast agent through the lymphatic channel to the sentinel lymph node. Lymph node biopsy was performed under ultrasound guidance, followed by an excisional biopsy of the lymph nodes and a regional mastectomy procedure. Excised tissues were submitted for histopathologic examination and evaluated as to whether they were representative of the node. The ultrasound contrast agent was easily visualized with ultrasound leading up to the sentinel lymph nodes. Eight normal lymph nodes (two inguinal, one axillary in two dogs; two inguinal in one dog) were identified and biopsied. Lymphoid tissue was obtained from all biopsy specimens. Samples from four of eight lymph nodes contained both cortical and medullary lymphoid tissue. Contrast-enhanced ultrasound can be successfully used to image and guide minimally invasive biopsy of the normal sentinel lymph nodes draining the mammary glands in healthy dogs. Further work is needed to evaluate whether this technique may be applicable in patients with breast cancer or other conditions warranting evaluation of sentinel lymph nodes in animals.
Synthetic aperture tissue and flow ultrasound imaging

DEFF Research Database (Denmark)

Nikolov, Svetoslav

imaging applied to medical ultrasound. It is divided into two major parts: tissue and blood flow imaging. Tissue imaging using synthetic aperture algorithms has been investigated for about two decades, but has not been implemented in medical scanners yet. Among the other reasons, the conventional scanning...... and beamformation methods are adequate for the imaging modalities in clinical use - the B-mode imaging of tissue structures, and the color mapping of blood flow. The acquisition time, however, is too long, and these methods fail to perform real-time three-dimensional scans. The synthetic transmit aperture......, on the other hand, can create a Bmode image with as little as 2 emissions, thus significantly speeding-up the scan procedure. The first part of the dissertation describes the synthetic aperture tissue imaging. It starts with an overview of the efforts previously made by other research groups. A classification...
ultrasound-guided shoulder arthrogram injection

African Journals Online (AJOL)

2008-10-15

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

Medline Plus

Full Text Available ... Children's (Pediatric) Ultrasound - Abdomen Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored by Please ...
Non-invasive estimation of temperature using diagnostic ultrasound during HIFU therapy

Science.gov (United States)

Georg, O.; Wilkens, V.

2017-03-01

The use of HIFU for thermal ablation of human tissues requires safe real-time monitoring of the lesion formation during the treatment to avoid damage of the surrounding healthy tissues and to control temperature rise. Besides MR imaging, several methods have been proposed for temperature imaging using diagnostic ultrasound, and echoshift estimation (using speckle tracking) is the most promising and commonly used technique. It is based on the thermal dependence of the ultrasound echo that accounts for two different physical phenomena: local change in speed of sound and thermal expansion of the propagating medium due to changes in temperature. In our experiments we have used two separate transducers: HIFU exposure was performed using a 1.06 MHz single element focusing transducer of 64 mm aperture and 63.2 mm focal length; the ultrasound diagnostic probe of 11 MHz operated in B-mode for image guidance. The temperature measurements were performed in an agar-based tissue-mimicking phantom. To verify the obtained results, numerical modeling of the acoustic and temperature fields was carried out using KZK and Pennes Bioheat equations, as well as measurements with thermocouples were performed.
Physics of tissue harmonic imaging by ultrasound

Science.gov (United States)

Jing, Yuan

Tissue Harmonic Imaging (THI) is an imaging modality that is currently deployed on diagnostic ultrasound scanners. In THI the amplitude of the ultrasonic pulse that is used to probe the tissue is large enough that the pulse undergoes nonlinear distortion as it propagates into the tissue. One result of the distortion is that as the pulse propagates energy is shifted from the fundamental frequency of the source pulse into its higher harmonics. These harmonics will scatter off objects in the tissue and images formed from the scattered higher harmonics are considered to have superior quality to the images formed from the fundamental frequency. Processes that have been suggested as possibly responsible for the improved imaging in THI include: (1) reduced sensitivity to reverberation, (2) reduced sensitivity to aberration, and (3) reduction in side lobes. By using a combination of controlled experiments and numerical simulations, these three reasons have been investigated. A single element transducer and a clinical ultrasound scanner with a phased array transducer were used to image a commercial tissue-mimicking phantom with calibrated targets. The higher image quality achieved with THI was quantified in terms of spatial resolution and "clutter" signals. A three-dimensional model of the forward propagation of nonlinear sound beams in media with arbitrary spatial properties (a generalized KZK equation) was developed. A time-domain code for solving the KZK equation was validated with measurements of the acoustic field generated by the single element transducer and the phased array transducer. The code was used to investigate the impact of aberration using tissue-like media with three-dimensional variations in all acoustic properties. The three-dimensional maps of tissue properties were derived from the datasets available through the Visible Female project. The experiments and simulations demonstrated that second harmonic imaging (1) suffers less clutter associated with
Fourier beamformation of multistatic synthetic aperture ultrasound imaging

DEFF Research Database (Denmark)

Moghimirad, Elahe; Villagómez Hoyos, Carlos Armando; Mahloojifar, Ali

2015-01-01

A new Fourier beamformation (FB) algorithm is presented for multistatic synthetic aperture ultrasound imaging. It can reduce the number of computations by a factor of 20 compared to conventional Delay-and-Sum (DAS) beamformers. The concept is based on the wavenumber algorithm from radar and sonar...
Ultrasound imaging in the diagnosis of periapical lesions

Directory of Open Access Journals (Sweden)

Christo Naveen Prince

2012-01-01

Full Text Available Background and Objectives: To assess the diagnostic capability of real-time ultrasound imaging, together with the application of color power Doppler in the identification and differential diagnosis of the periapical lesions. Materials and Methods: Fifteen patients with periapical lesions of pulpal origin, diagnosed with clinical and conventional radiographic examination, were examined further using ultrasonography. The results from the biopsies of the lesions were compared and statistically analyzed. Results: The differential diagnosis between periapical granulomas and cystic lesions, which were based on the ultrasonographic findings, were confirmed by the results of the histopathologic examination in 13 (86.7% of 15 cases, one being granuloma and 14 being cystic lesion. Interpretation and Conclusion: Ultrasound real-time imaging is a technique that may help make a differential diagnosis between cysts and granulomas by revealing the nature of the content of a bony lesion. This technique may have further applications in the study of other lesions of the jaws.

Using passive cavitation images to classify high-intensity focused ultrasound lesions.

Science.gov (United States)

Haworth, Kevin J; Salgaonkar, Vasant A; Corregan, Nicholas M; Holland, Christy K; Mast, T Douglas

2015-09-01

Passive cavitation imaging provides spatially resolved monitoring of cavitation emissions. However, the diffraction limit of a linear imaging array results in relatively poor range resolution. Poor range resolution has limited prior analyses of the spatial specificity and sensitivity of passive cavitation imaging in predicting thermal lesion formation. In this study, this limitation is overcome by orienting a linear array orthogonal to the high-intensity focused ultrasound propagation direction and performing passive imaging. Fourteen lesions were formed in ex vivo bovine liver samples as a result of 1.1-MHz continuous-wave ultrasound exposure. The lesions were classified as focal, "tadpole" or pre-focal based on their shape and location. Passive cavitation images were beamformed from emissions at the fundamental, harmonic, ultraharmonic and inharmonic frequencies with an established algorithm. Using the area under a receiver operating characteristic curve (AUROC), fundamental, harmonic and ultraharmonic emissions were found to be significant predictors of lesion formation for all lesion types. For both harmonic and ultraharmonic emissions, pre-focal lesions were classified most successfully (AUROC values of 0.87 and 0.88, respectively), followed by tadpole lesions (AUROC values of 0.77 and 0.64, respectively) and focal lesions (AUROC values of 0.65 and 0.60, respectively). Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Compton scatter imaging: A promising modality for image guidance in lung stereotactic body radiation therapy.

Science.gov (United States)

Redler, Gage; Jones, Kevin C; Templeton, Alistair; Bernard, Damian; Turian, Julius; Chu, James C H

2018-03-01

Lung stereotactic body radiation therapy (SBRT) requires delivering large radiation doses with millimeter accuracy, making image guidance essential. An approach to forming images of patient anatomy from Compton-scattered photons during lung SBRT is presented. To investigate the potential of scatter imaging, a pinhole collimator and flat-panel detector are used for spatial localization and detection of photons scattered during external beam therapy using lung SBRT treatment conditions (6 MV FFF beam). MCNP Monte Carlo software is used to develop a model to simulate scatter images. This model is validated by comparing experimental and simulated phantom images. Patient scatter images are then simulated from 4DCT data. Experimental lung tumor phantom images have sufficient contrast-to-noise to visualize the tumor with as few as 10 MU (0.5 s temporal resolution). The relative signal intensity from objects of different composition as well as lung tumor contrast for simulated phantom images agree quantitatively with experimental images, thus validating the Monte Carlo model. Scatter images are shown to display high contrast between different materials (lung, water, bone). Simulated patient images show superior (~double) tumor contrast compared to MV transmission images. Compton scatter imaging is a promising modality for directly imaging patient anatomy during treatment without additional radiation, and it has the potential to complement existing technologies and aid tumor tracking and lung SBRT image guidance. © 2018 American Association of Physicists in Medicine.
Real-time interpolation for true 3-dimensional ultrasound image volumes.

Science.gov (United States)

Ji, Songbai; Roberts, David W; Hartov, Alex; Paulsen, Keith D

2011-02-01

We compared trilinear interpolation to voxel nearest neighbor and distance-weighted algorithms for fast and accurate processing of true 3-dimensional ultrasound (3DUS) image volumes. In this study, the computational efficiency and interpolation accuracy of the 3 methods were compared on the basis of a simulated 3DUS image volume, 34 clinical 3DUS image volumes from 5 patients, and 2 experimental phantom image volumes. We show that trilinear interpolation improves interpolation accuracy over both the voxel nearest neighbor and distance-weighted algorithms yet achieves real-time computational performance that is comparable to the voxel nearest neighbor algrorithm (1-2 orders of magnitude faster than the distance-weighted algorithm) as well as the fastest pixel-based algorithms for processing tracked 2-dimensional ultrasound images (0.035 seconds per 2-dimesional cross-sectional image [76,800 pixels interpolated, or 0.46 ms/1000 pixels] and 1.05 seconds per full volume with a 1-mm(3) voxel size [4.6 million voxels interpolated, or 0.23 ms/1000 voxels]). On the basis of these results, trilinear interpolation is recommended as a fast and accurate interpolation method for rectilinear sampling of 3DUS image acquisitions, which is required to facilitate subsequent processing and display during operating room procedures such as image-guided neurosurgery.
Ultrasound Imaging. Chapter 13

Energy Technology Data Exchange (ETDEWEB)

Lacefield, J. C. [University of Western Ontario, London (Canada)

2014-09-15

In the conventional method of ultrasonography, images are acquired in reflection, or pulse echo, mode. An array of small piezoelectric elements transmits a focused pulse along a specified line of sight known as a scan line. Echoes returning from the tissue are received by the same array, focused via the delay-and-sum beam forming process reviewed in Section 13.2, and demodulated to obtain the magnitude, or envelope, of the echo signal. The scanner measures the arrival time of the echoes relative to the time the pulse was transmitted and maps the arrival time to the distance from the array, using an assumed speed of sound. The earliest ultrasound systems would display the result of a single pulse acquisition in 1-D A-mode (amplitude mode) format by plotting echo magnitude as a function of distance. A 2-D or 3-D B-mode (brightness mode) image is acquired by performing a large number of pulse echo acquisitions, incrementally increasing the scan line direction between each pulse echo operation, to sweep out a 2-D or 3-D field of view (FOV). The term B-mode imaging reflects the fact that the echo magnitude from each point in the FOV is mapped to the grey level, or brightness, of the corresponding pixel in the image.
Pulsed radiofrequency on radial nerve under ultrasound guidance for treatment of intractable lateral epicondylitis.

Science.gov (United States)

Oh, Dae Seok; Kang, Tae Hyung; Kim, Hyae Jin

2016-06-01

Lateral epicondylitis is a painful and functionally limiting disorder. Although lateral elbow pain is generally self-limiting, in a minority of people symptoms persist for a long time. When various conservative treatments fail, surgical approach is recommended. Surgical denervation of several nerves that innervate the lateral humeral epicondyle could be considered in patients with refractory pain because it denervates the region of pain. Pulsed radiofrequency is a minimally invasive procedure that improves chronic pain when applied to various neural tissues without causing any significant destruction and painful complication. This procedure is safe, minimally invasive, and has less risk of complications relatively compared to the surgical approach. The radial nerve can be identified as a target for pulsed radiofrequency lesioning in lateral epicondylitis. This innovative method of pulsed radiofrequency applied to the radial nerve has not been reported before. We reported on two patients with intractable lateral epicondylitis suffering from elbow pain who did not respond to nonoperative treatments, but in whom the ultrasound-guided pulsed radiofrequency neuromodulation of the radial nerve induced symptom improvement. After a successful diagnostic nerve block, radiofrequency probe adjustment around the radial nerve was performed on the lateral aspect of the distal upper arm under ultrasound guidance and multiple pulsed treatments were applied. A significant reduction in pain was reported over the follow-up period of 12 weeks.
[Monitoring radiofrequency ablation by ultrasound temperature imaging and elastography under different power intensities].

Science.gov (United States)

Geng, Xiaonan; Li, Qiang; Tsui, Pohsiang; Wang, Chiaoyin; Liu, Haoli

2013-09-01

To evaluate the reliability of diagnostic ultrasound-based temperature and elasticity imaging during radiofrequency ablation (RFA) through ex vivo experiments. Procine liver samples (n=7) were employed for RFA experiments with exposures of different power intensities (10 and 50w). The RFA process was monitored by a diagnostic ultrasound imager and the information were postoperatively captured for further temperature and elasticity image analysis. Infrared thermometry was concurrently applied to provide temperature change calibration during the RFA process. Results from this study demonstrated that temperature imaging was valid under 10 W RF exposure (r=0.95), but the ablation zone was no longer consistent with the reference infrared temperature distribution under high RF exposures. The elasticity change could well reflect the ablation zone under a 50 W exposure, whereas under low exposures, the thermal lesion could not be well detected due to the limited range of temperature elevation and incomplete tissue necrosis. Diagnostic ultrasound-based temperature and elastography is valid for monitoring thr RFA process. Temperature estimation can well reflect mild-power RF ablation dynamics, whereas the elastic-change estimation can can well predict the tissue necrosis. This study provide advances toward using diagnostic ultrasound to monitor RFA or other thermal-based interventions.
[Magnetic resonance imaging as a prenatal diagnostic tool supplementary to ultrasound in diagnosing fetal and gestational abnormalities].

Science.gov (United States)

Porat, Shay; Agid, Ronit; Elchalal, Uriel; Ezra, Yossi; Gomori, J Moshe; Nadjari, Michelle

2002-04-01

The use of Magnetic Resonance Imaging (MRI) as a prenatal and gestational imaging modality supplementary to ultrasound has become widespread with the advent of rapid MR sequences in the last few years. These sequences allow acquisition of high-resolution images of the fetus in a single breath-holding period of the mother, with minimal fetal motion artifacts. We describe our experience with this modality in the diagnosis of prenatal and gestational abnormalities. The study population consisted of 39 pregnant women who had a total of 40 MRI examinations from 7/1998 to 7/2000. The indication for all examinations was a suspected fetal or gestational abnormality as suggested by ultrasound scan, laboratory tests or by family history. In 31 cases (77.5%) a correlation was found between the ultrasound findings and the MR imaging, of which in 6 cases (15%) the MRI added new valuable information. In 9 cases (22.5%) the MRI ruled out findings suspected by ultrasound. The prenatal findings were compared with postnatal clinical follow-up, imaging or pathology report in 26 cases (66.6%). In two cases the clinical outcome and postnatal imaging were discordant with the prenatal imaging findings in ultrasound and MRI. Although not proven, MRI is considered safe during pregnancy because it does not use ionizing radiation. It depicts fetal anatomy and pathology well. Also uterine, placental and other maternal structures are well demonstrated. This tool is useful in cases in which there is a suspicion of a malformed fetus or abnormal placenta by an ultrasound examination or in cases in which an ultrasound examination is limited by technical factors. MRI was found to help parents and doctors decide about the fate of a suspected abnormal pregnancy by adding valuable information supplemental to ultrasound examination.
Ultrasound guided reduction of childhood intussusception

International Nuclear Information System (INIS)

Yoon, Chong Hyun; Kim, Han Suk

1986-01-01

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

Science.gov (United States)

Nandagopalan, S; Suryanarayana, Adiga B; Sudarshan, T S B; Chandrashekar, Dhanalakshmi; Manjunath, C N

2013-01-01

This paper proposes a novel method to analyze and classify the cardiovascular ultrasound echocardiographic images using Naïve-Bayesian model via database OLAP-SQL. Efficient data mining algorithms based on tightly-coupled model is used to extract features. Three algorithms are proposed for classification namely Naïve-Bayesian Classifier for Discrete variables (NBCD) with SQL, NBCD with OLAP-SQL, and Naïve-Bayesian Classifier for Continuous variables (NBCC) using OLAP-SQL. The proposed model is trained with 207 patient images containing normal and abnormal categories. Out of the three proposed algorithms, a high classification accuracy of 96.59% was achieved from NBCC which is better than the earlier methods.
Microfluidics-based microbubbles in methylene blue solution for photoacoustic and ultrasound imaging

Science.gov (United States)

Das, Dhiman; Sivasubramanian, Kathyayini; Yang, Chun; Pramanik, Manojit

2018-02-01

Contrast agents which can be used for more than one bio-imaging technique has gained a lot of attention from researchers in recent years. In this work, a microfluidic device employing a flow-focusing junction, is used for the continuous generation of monodisperse nitrogen microbubbles in methylene blue, an optically absorbing organic dye, for dual-modal photoacoustic and ultrasound imaging. Using an external phase of polyoxyethylene glycol 40 stearate (PEG 40), a non-ionic surfactant, and 50% glycerol solution at a flow rate of 1 ml/hr and gas pressure at 1.75 bar, monodisperse nitrogen microbubbles of diameter 7 microns were obtained. The external phase also contained methylene blue hydrate at a concentration of 1 gm/litre. The monodisperse microbubbles produced a strong ultrasound signal as expected. It was observed that the signal-to-noise (SNR) ratio of the photoacoustic signal for the methylene blue solution in the presence of the monodisperse microbubbles was 68.6% lower than that of methylene blue solution in the absence of microbubbles. This work is of significance because using microfluidics, we can precisely control the bubbles' production rate and bubble size which increases ultrasound imaging efficiency. A uniform size distribution of the bubbles will have narrower resonance frequency bandwidth which will respond well to specific ultrasound frequencies.
Development of an Anthropomorphic Breast Phantom for Combined PET, B-Mode Ultrasound and Elastographic Imaging

CERN Document Server

Dang, J; Tavernier, S; Lasaygues, P; Mensah, S; Zhang, D C; Auffray, E; Frisch, B; Varela, J; Wan, M X; Felix, N

2011-01-01

Combining the advantages of different imaging modalities leads to improved clinical results. For example, ultrasound provides good real-time structural information without any radiation and PET provides sensitive functional information. For the ongoing ClearPEM-Sonic project combining ultrasound and PET for breast imaging, we developed a dual-modality PET/Ultrasound (US) phantom. The phantom reproduces the acoustic and elastic properties of human breast tissue and allows labeling the different tissues in the phantom with different concentrations of FDG. The phantom was imaged with a whole-body PET/CT and with the Supersonic Imagine Aixplorer system. This system allows both B-mode US and shear wave elastographic imaging. US elastography is a new imaging method for displaying the tissue elasticity distribution. It was shown to be useful in breast imaging. We also tested the phantom with static elastography. A 6D magnetic positioning system allows fusing the images obtained with the two modalities. ClearPEM-Soni...
Active instrumental guidance in interventional magnetic resonance imaging

International Nuclear Information System (INIS)

Wildermuth, S.; Erhart, P.; Leung, D.A.; Goehde, S.; Schoenenberger, A.; Debatin, J.F.

1998-01-01

Purpose: An active MR-based guidance system for visualisation of invasive instruments is described. Methods: The principle of MR tracking is based on the integration of a miniaturised coil into the tip of the instrument itself. A phantom experiment was designed to demonstrate the localising accuracy of this technique. In [dition, bicompatibility and warming effects were evaluated. Preliminary intravascular applications that were performed in animal experiments under MR guidance included embolisation, vascular occlusion as well as transjugular intrahepatic punctures. Percutaneous biopsies, cholecystostomies and laparoscopic applications were also evaluated with MR tracking. Results: Phantom experiments confirmed an excellent localisation accuracy of MR tracking compared to conventional r[iography. At a field strength of 0.5 T, the temperature increase remained below 2 C. Results of phantom experiments revealed a potential of significant heating dependent on the sequence parameters employed. MR tracking allowed a robust, simultaneously biplanar visualisation of the instrument tips in real time. Based on MR 'ro[ map' images, various intravascular and percutaneous interventions were successfully performed in vivo under MR guidance. Conclusions: MR tracking is a flexible concept permitting monitoring in the guidance of instruments in an MR environment. Various preliminary in vitro and in vivo experiments demonstrate safety, localisation accuracy and feasibility of this biplanar localisation technique in real time. (orig.) [de
Bedside Ultrasound for the Diagnosis of Peritonsillar Abscess

Directory of Open Access Journals (Sweden)

Harshal Bhakta

2017-09-01

Full Text Available History of present illness: A 34-year-old male presented to the Emergency Department with fever, sore throat, and difficulty swallowing. On exam, the patient had trismus, a deviated uvula, and swelling of his left peritonsillar space. An intraoral point of care ultrasound (POCUS was performed, which revealed a fluid collection in the patient’s left peritonsillar space. The patient was diagnosed with a peritonsillar abscess (PTA and needle aspiration was performed under direct ultrasound guidance. The patient tolerated the procedure well and was sent home with a course of antibiotics. Significant findings: The first video is an intraoral ultrasound using the high frequency endocavitary probe demonstrating an anechoic fluid collection adjacent to the patient’s enlarged left tonsil. The second video shows real-time ultrasound-guided successful drainage of the PTA. Discussion: Peritonsillar abscesses are the most common deep space infection of the head and neck1, most commonly affecting children and young adults.2 The ability of physicians to accurately differentiate PTA from peritonsillar cellulitis (PTC by physical exam alone is limited. Traditionally, PTA has been treated using landmark-based needle aspiration.3 If unsuccessful, computed tomography (CT imaging and otolaryngology (ENT consultation is usually required.3 Although diagnosis of PTA using intraoral ultrasound has a sensitivity and specificity of between 89%-95% and 79%-100% respectively, it is still underutilized in comparison to these traditional methods.4 Studies have shown the use of ultrasound for diagnosis and treatment of PTA leads to significantly better outcomes and higher success rates of drainage (when compared to landmark-based needle aspiration, less need for CT imaging, and less need for ENT consultation.3 Utilizing intraoral point-of-care ultrasound is an efficient, safe, and cost-effective way of diagnosing and treating PTA.
Ultrasound-Guided Intervention for Treatment of Trigeminal Neuralgia: An Updated Review of Anatomy and Techniques

Directory of Open Access Journals (Sweden)

Abdallah El-Sayed Allam

2018-01-01

Full Text Available Orofacial myofascial pain is prevalent and most often results from entrapment of branches of the trigeminal nerves. It is challenging to inject branches of the trigeminal nerve, a large portion of which are shielded by the facial bones. Bony landmarks of the cranium serve as important guides for palpation-guided injections and can be delineated using ultrasound. Ultrasound also provides real-time images of the adjacent muscles and accompanying arteries and can be used to guide the needle to the target region. Most importantly, ultrasound guidance significantly reduces the risk of collateral injury to vital neurovascular structures. In this review, we aimed to summarize the regional anatomy and ultrasound-guided injection techniques for the trigeminal nerve and its branches, including the supraorbital, infraorbital, mental, auriculotemporal, maxillary, and mandibular nerves.
Poster - 10: QA of Ultrasound Images for Prostate Brachytherapy

Energy Technology Data Exchange (ETDEWEB)

Szpala, Stanislaw; Kohli, Kirpal S. [BCCA-Fraser Valley Centre (Canada)

2016-08-15

Purpose: The current QA protocol of ultrasound systems used in prostate brachytherapy (TG128) addresses geometrical verifications, but the scope of evaluation of image quality is limited. We recognized importance of the latter in routine practice, and designed a protocol for QA of the images. Methods: Images of an ultrasound prostate phantom (CIRS053) were collected with BK Flex Focus 400. The images were saved as bmp after adjusting the gain to 50% for consistent results. Mean pixel values and signal to noise ratio were inspected in the representative sections of the phantom, including the mock prostate and the unechoic medium. Constancy of these numbers over a one year period was looked at. Results: The typical intensity in the mock prostate region in the transverse images ranged between 95 and 118 (out of 256), and the signal to noise was about 10. The intensity in the urethra region was about 170±40, and the unechoic medium was 2±2. The mean and the signal to noise ratio remained almost unchanged after a year, while the signal in the unechoic medium increased to about 7±4. Similar values were obtained in the sagittal images. Conclusions: The image analysis discussed above allows quick evaluation of constancy of the image quality. This may be also useful in troubleshooting image-quality problems during routine exams, which might not be due to deterioration of the US system, but other reasons, e.g. variations in tissue properties or air being trapped between the probe and the anatomy.
Validation of Ultrasound Imaging to Rule-out Thoracic Trauma on the International Space Station

Science.gov (United States)

Hamilton, Douglas R.; Sargsyan, Ashot E.; Melton, Shannon; Martin, David; Dulchavsky, Scott A.

2006-01-01

Introduction: Aboard the International Space Station (ISS) an intra-thoracic injury may be disastrous to the crew member if the diagnosis is missed or even delayed. Pneumothorax and hemothorax commonly seen in trauma patients; the diagnosis is usually confirmed by chest X-ray or computed tomography. In this study, the ability of ultrasound to rule out pneumothorax by the presence "lung sliding" and hemothorax by the absence of pleural fluid was validated. Methods: The research activities were approved by the NASA Johnson Space Center Committee for the Protection of Human Subjects, and the participating crewmembers signed informed consent prior to the activity. ISS crewmembers received 2-hours of "hands on" ultrasound training 8 months prior to the on-orbit ultrasound exam. Baseline ultrasound images of the thorax were acquired on the crewmebers of Increment 8 and 9 prior to launch from Bakonur, Russia. Ultrasound examination of the thorax were performed on crewmembers at 30 day intervals (n=??) throughout their flight. Post flight images were acquired on or about landing day 10. Ultrasound images were acquired using the ISS Health Research Facility ultrasound system and examined by experts on the ground to rule out the presence of pneumothorax and hemothorax. Results: The presence of "lung sliding" which excludes pneumothorax, was seen in all subjects. The absence of pleural fluid, which excludes hemothorax was seen in all subjects. The optimal position between sonographer and patient under microgravity conditions and the amount and type of training for a non-physician crew medical officer for these procedures was also established for this procedure. Conclusion: Ultrasound can be performed on orbit under microgravity condition to rule thoracic trauma, such as pneumothorax and hemothorax.
Robotic needle steering: design, modeling, planning, and image guidance

NARCIS (Netherlands)

Cowan, Noah J.; Goldberg, Ken; Chirikjian, Gregory S.; Fichtinger, Gabor; Alterovitz, Ron; Reed, Kyle B.; Kallem, Vinutha; Misra, Sarthak; Park, Wooram; Okamura, Allison M.; Rosen, Jacob; Hannaford, Blake; Satava, Richard M.

2010-01-01

This chapter describes how advances in needle design, modeling, planning, and image guidance make it possible to steer flexible needles from outside the body to reach specified anatomical targets not accessible using traditional needle insertion methods. Steering can be achieved using a variety of
Spatio-Temporal Encoding in Medical Ultrasound Imaging

DEFF Research Database (Denmark)

Gran, Fredrik

2005-01-01

In this dissertation two methods for spatio-temporal encoding in medical ultrasound imaging are investigated. The first technique is based on a frequency division approach. Here, the available spectrum of the transducer is divided into a set of narrow bands. A waveform is designed for each band...... the signal to noise ratio and simultaneously the penetration depth so that the medical doctor can image deeper lying structures. The method is tested both experimentally and in simulation and has also evaluated for the purpose of blood flow estimation. The work presented is based on four papers which...
Fabrication and imaging study of ultrasound/fluorescence bi-modal contrast agent based on polymeric microbubbles

International Nuclear Information System (INIS)

Xing Zhanwen; Ke Hengte; Wang Jinrui; Zhao Bo; Qu Enze; Yue Xiuli; Dai Zhifei

2013-01-01

Objective: To fabricate an ultrasound/fluorescence bi-modal contrast agent by encapsulating fluorescent quantum dots into polymeric ultrasound contrast agent microbubbles. Methods: Polylactic acid (PLA, 500 mg), (1R)-(+)-camphor (50 mg) and CdSe/ZnS quantum dots (0.5 ml, 2.3 μmol/L)were dissolved or dispersed in dichloromethane (10 ml) to form in an organic phase. Ammonium carbonate solution and poly (vinyl alcohol) solution were employed as the internal and external water phase, respectively. The fluorescent microbubbles were generated using double emulsion solvent evaporation and lyophilization methods. The morphology and illumination were characterized by scanning electron microscopy (SEM) and fluorescence spectrophotometry. Synchronized contrast-enhanced ultrasound and fluorescence imaging was acquired by injecting fluorescent microbubbles into the silicone tube coupled to a self-made ultrasound/fluorescence imaging device. Ultrasound/fluorescence bi-modal in vivo imaging was acquired on the kidney of New Zealand rabbits and suckling mice. Results: The fluorescent microbubbles were hollow spheres with an averaged diameter of (1.62 ± 1.47) μm. More than 99% of these microbubbles were less than 8 μm in diameter, which met the size criteria for ultrasound contrast agents. The fluorescence emission peak of the microbubbles appeared at 632 nm, indicating that good luminescence properties of quantum dots were maintained. In vitro ultrasound/fluorescence imaging showed no echoic signal when the silicone tube was filled with saline, but there was a strong echo when filled with fluorescent microbubbles. The liquid column with fluorescent microbubbles emitted red luminescence under ultraviolet irradiation. The kidney of the rabbit was remarkably enhanced after the administration of fluorescent microbubbles. Bright fluorescence could be observed at the injection site of the suckling mice via subcutaneous injection. Conclusions: A bi-modal but single contrast agent
Use of modulated excitation signals in ultrasound. Part II: Design and performance for medical imaging applications

DEFF Research Database (Denmark)

Misaridis, Thanassis; Jensen, Jørgen Arendt

2005-01-01

ultrasound presents design methods of linear FM signals and mismatched filters, in order to meet the higher demands on resolution in ultrasound imaging. It is shown that for the small time-bandwidth (TB) products available in ultrasound, the rectangular spectrum approximation is not valid, which reduces....... The method is evaluated first for resolution performance and axial sidelobes through simulations with the program Field II. A coded excitation ultrasound imaging system based on a commercial scanner and a 4 MHz probe driven by coded sequences is presented and used for the clinical evaluation of the coded...... excitation/compression scheme. The clinical images show a significant improvement in penetration depth and contrast, while they preserve both axial and lateral resolution. At the maximum acquisition depth of 15 cm, there is an improvement of more than 10 dB in the signal-to-noise ratio of the images...

Image guidance in trans-sphenoidal surgery for giant pituitary adenomas: Luxury or necessity?

OpenAIRE

Deepak Agrawal

2012-01-01

Background: In spite of availability of image guidance (neuronavigation) at major centers around the world, most trans-sphenoidal surgeries for pituitary adenomas continue to be done under fluoroscopic control. On the other hand, the high mortality and morbidity for giant pituitary adenomas is mainly due to inadequate tumor removal. Aims and Objectives: The objective of this study was to study to utility of image guidance in trans-sphenoidal surgeries for optimizing tumor removal in giant pit...
SU-E-E-06: Teaching About the Gamma Camera and Ultrasound Imaging

International Nuclear Information System (INIS)

Lowe, M; Spiro, A; Vogel, R; Donaldson, N; Gosselin, C

2015-01-01

Purpose: Instructional modules on applications of physics in medicine are being developed. The target audience consists of students who have had an introductory undergraduate physics course. This presentation will concentrate on an active learning approach to teach the principles of the gamma camera. There will also be a description of an apparatus to teach ultrasound imaging. Methods: Since a real gamma camera is not feasible in the undergraduate classroom, we have developed two types of optical apparatus that teach the main principles. To understand the collimator, LEDS mimic gamma emitters in the body, and the photons pass through an array of tubes. The distance, spacing, diameter, and length of the tubes can be varied to understand the effect upon the resolution of the image. To determine the positions of the gamma emitters, a second apparatus uses a movable green laser, fluorescent plastic in lieu of the scintillation crystal, acrylic rods that mimic the PMTs, and a photodetector to measure the intensity. The position of the laser is calculated with a centroid algorithm.To teach the principles of ultrasound imaging, we are using the sound head and pulser box of an educational product, variable gain amplifier, rotation table, digital oscilloscope, Matlab software, and phantoms. Results: Gamma camera curriculum materials have been implemented in the classroom at Loyola in 2014 and 2015. Written work shows good knowledge retention and a more complete understanding of the material. Preliminary ultrasound imaging materials were run in 2015. Conclusion: Active learning methods add another dimension to descriptions in textbooks and are effective in keeping the students engaged during class time. The teaching apparatus for the gamma camera and ultrasound imaging can be expanded to include more cases, and could potentially improve students’ understanding of artifacts and distortions in the images
SU-E-E-06: Teaching About the Gamma Camera and Ultrasound Imaging

Energy Technology Data Exchange (ETDEWEB)

Lowe, M; Spiro, A [Loyola University Maryland, Baltimore, Maryland (United States); Vogel, R [Iowa Doppler Products, Iowa City, Iowa (United States); Donaldson, N; Gosselin, C [Rockhurst University, Kansas City, MO (United States)

2015-06-15

Purpose: Instructional modules on applications of physics in medicine are being developed. The target audience consists of students who have had an introductory undergraduate physics course. This presentation will concentrate on an active learning approach to teach the principles of the gamma camera. There will also be a description of an apparatus to teach ultrasound imaging. Methods: Since a real gamma camera is not feasible in the undergraduate classroom, we have developed two types of optical apparatus that teach the main principles. To understand the collimator, LEDS mimic gamma emitters in the body, and the photons pass through an array of tubes. The distance, spacing, diameter, and length of the tubes can be varied to understand the effect upon the resolution of the image. To determine the positions of the gamma emitters, a second apparatus uses a movable green laser, fluorescent plastic in lieu of the scintillation crystal, acrylic rods that mimic the PMTs, and a photodetector to measure the intensity. The position of the laser is calculated with a centroid algorithm.To teach the principles of ultrasound imaging, we are using the sound head and pulser box of an educational product, variable gain amplifier, rotation table, digital oscilloscope, Matlab software, and phantoms. Results: Gamma camera curriculum materials have been implemented in the classroom at Loyola in 2014 and 2015. Written work shows good knowledge retention and a more complete understanding of the material. Preliminary ultrasound imaging materials were run in 2015. Conclusion: Active learning methods add another dimension to descriptions in textbooks and are effective in keeping the students engaged during class time. The teaching apparatus for the gamma camera and ultrasound imaging can be expanded to include more cases, and could potentially improve students’ understanding of artifacts and distortions in the images.
Mobile C-arm cone-beam CT for guidance of spine surgery: Image quality, radiation dose, and integration with interventional guidance

Energy Technology Data Exchange (ETDEWEB)

Schafer, S.; Nithiananthan, S.; Mirota, D. J.; Uneri, A.; Stayman, J. W.; Zbijewski, W.; Schmidgunst, C.; Kleinszig, G.; Khanna, A. J.; Siewerdsen, J. H. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 (United States); Department of Computer Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States); Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 (United States); Siemens Healthcare XP Division, Erlangen (Germany); Department of Orthopaedic Surgery, Johns Hopkins University, Baltimore, Maryland 21239 (United States); Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21202 and Department of Computer Science, Johns Hopkins University, Baltimore, Maryland 21218 (United States)

2011-08-15

Purpose: A flat-panel detector based mobile isocentric C-arm for cone-beam CT (CBCT) has been developed to allow intraoperative 3D imaging with sub-millimeter spatial resolution and soft-tissue visibility. Image quality and radiation dose were evaluated in spinal surgery, commonly relying on lower-performance image intensifier based mobile C-arms. Scan protocols were developed for task-specific imaging at minimum dose, in-room exposure was evaluated, and integration of the imaging system with a surgical guidance system was demonstrated in preclinical studies of minimally invasive spine surgery. Methods: Radiation dose was assessed as a function of kilovolt (peak) (80-120 kVp) and milliampere second using thoracic and lumbar spine dosimetry phantoms. In-room radiation exposure was measured throughout the operating room for various CBCT scan protocols. Image quality was assessed using tissue-equivalent inserts in chest and abdomen phantoms to evaluate bone and soft-tissue contrast-to-noise ratio as a function of dose, and task-specific protocols (i.e., visualization of bone or soft-tissues) were defined. Results were applied in preclinical studies using a cadaveric torso simulating minimally invasive, transpedicular surgery. Results: Task-specific CBCT protocols identified include: thoracic bone visualization (100 kVp; 60 mAs; 1.8 mGy); lumbar bone visualization (100 kVp; 130 mAs; 3.2 mGy); thoracic soft-tissue visualization (100 kVp; 230 mAs; 4.3 mGy); and lumbar soft-tissue visualization (120 kVp; 460 mAs; 10.6 mGy) - each at (0.3 x 0.3 x 0.9 mm{sup 3}) voxel size. Alternative lower-dose, lower-resolution soft-tissue visualization protocols were identified (100 kVp; 230 mAs; 5.1 mGy) for the lumbar region at (0.3 x 0.3 x 1.5 mm{sup 3}) voxel size. Half-scan orbit of the C-arm (x-ray tube traversing under the table) was dosimetrically advantageous (prepatient attenuation) with a nonuniform dose distribution ({approx}2 x higher at the entrance side than at isocenter
A new coding concept for fast ultrasound imaging using pulse trains

DEFF Research Database (Denmark)

Misaridis, T.; Jensen, Jørgen Arendt

2002-01-01

Frame rate in ultrasound imaging can he increased by simultaneous transmission of multiple beams using coded waveforms. However, the achievable degree of orthogonality among coded waveforms is limited in ultrasound, and the image quality degrades unacceptably due to interbeam interference....... In this paper, an alternative combined time-space coding approach is undertaken. In the new method all transducer elements are excited with short pulses and the high time-bandwidth (TB) product waveforms are generated acoustically. Each element transmits a short pulse spherical wave with a constant transmit...... delay from element to element, long enough to assure no pulse overlapping for all depths in the image. Frequency shift keying is used for "per element" coding. The received signals from a point scatterer are staggered pulse trains which are beamformed for all beam directions and further processed...
[Achilles tendon xanthoma imaging on ultrasound and magnetic resonance imaging].

Science.gov (United States)

Fernandes, Eloy de Ávila; Santos, Eduardo Henrique Sena; Tucunduva, Tatiana Cardoso de Mello; Ferrari, Antonio J L; Fernandes, Artur da Rocha Correa

2015-01-01

The Achilles tendon xanthoma is a rare disease and has a high association with primary hyperlipidemia. An early diagnosis is essential to start treatment and change the disease course. Imaging exams can enhance diagnosis. This study reports the case of a 60-year-old man having painless nodules on his elbows and Achilles tendons without typical gout crisis, followed in the microcrystalline disease clinic of Unifesp for diagnostic workup. Laboratory tests obtained showed dyslipidemia. The ultrasound (US) showed a diffuse Achilles tendon thickening with hypoechoic areas. Magnetic resonance imaging (MRI) showed a diffuse tendon thickening with intermediate signal areas, and a reticulate pattern within. Imaging studies showed relevant aspects to diagnose a xanthoma, thus helping in the differential diagnosis. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.
Model-Based Reconstructive Elasticity Imaging Using Ultrasound

Directory of Open Access Journals (Sweden)

Salavat R. Aglyamov

2007-01-01

Full Text Available Elasticity imaging is a reconstructive imaging technique where tissue motion in response to mechanical excitation is measured using modern imaging systems, and the estimated displacements are then used to reconstruct the spatial distribution of Young's modulus. Here we present an ultrasound elasticity imaging method that utilizes the model-based technique for Young's modulus reconstruction. Based on the geometry of the imaged object, only one axial component of the strain tensor is used. The numerical implementation of the method is highly efficient because the reconstruction is based on an analytic solution of the forward elastic problem. The model-based approach is illustrated using two potential clinical applications: differentiation of liver hemangioma and staging of deep venous thrombosis. Overall, these studies demonstrate that model-based reconstructive elasticity imaging can be used in applications where the geometry of the object and the surrounding tissue is somewhat known and certain assumptions about the pathology can be made.
Harmonic Contrast-Enhanced Endoscopic Ultrasonography for the Guidance of Fine-Needle Aspiration in Solid Pancreatic Masses

DEFF Research Database (Denmark)

Seicean, A; Badea, R; Moldovan-Pop, A

2015-01-01

Purpose: The global accuracy of fine-needle aspiration guided by endoscopic ultrasound (EUS-FNA) for pancreatic adenocarcinoma is about 85 %. The use of contrast agents during EUS to highlight vessels and the necrotic parts of pancreatic masses may improve biopsy guidance. Our aim was to assess...... whether the guidance of FNA by harmonic contrast-enhanced endoscopic ultrasound (CH-EUS) would increase diagnostic accuracy relative to conventional EUS-FNA in the same pancreatic masses. Patients and Methods: In a prospective study, EUS-FNA was performed in patients with pancreatic masses on CT scan......, followed by harmonic CH-EUS using SonoVue. A second cluster of CH-EUS-FNA was performed on contrast-enhanced images. The final diagnosis was based on the results of EUS-FNA and surgery, or the findings after 12 months' follow-up. Results: The final diagnosis was adenocarcinoma (n = 35), chronic...
Prostate Ultrasound

Medline Plus

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

International Nuclear Information System (INIS)

Schaeffeler, Christoph; Bruegel, M.; Waldt, S.; Rummeny, E.J.; Woertler, K.

2010-01-01

Purpose: To evaluate ultrasound guidance for intraarticular contrast injection via an anterolateral approach in comparison with fluoroscopic guidance. Materials and Methods: Contrast agent injection was performed in 40 consecutive patients, 20 under sonographic guidance and 20 under fluoroscopic guidance. None of the patients had previous shoulder surgery. The procedure time was measured and the efficiency of joint distension, incidence of extravasation and intraarticular air on the consecutive MR arthrograms were assessed by three blinded radiologists with musculoskeletal radiology experience. Statistical analysis was performed using the Kruskal-Wallis test. Results: Intraarticular contrast injection was successfully accomplished in all 40 patients. Subsequent MR arthrograms did not show any significant difference between sonographic and fluoroscopic guidance with respect to diagnostic quality, joint distension (p = 0.6665), intraarticular air bubbles (p = 0.1567) and occurrence of contrast extravasation (p = 0.8565). The mean duration of ultrasound-guided injection was 7:30 min compared to a shorter procedure time of 4:15 min for fluoroscopic guidance. In both groups, no procedural complications were observed. Conclusion: Ultrasound-guided injection for MR arthrography of the shoulder via an anterolateral approach represents a simple, safe, and effective technique which yields comparable results to those of injection under fluoroscopic guidance, but is slightly more time-consuming. (orig.)
Survey of the prevalence and methodology of quality assurance for B-mode ultrasound image quality among veterinary sonographers.

Science.gov (United States)

Hoscheit, Larry P; Heng, Hock Gan; Lim, Chee Kin; Weng, Hsin-Yi

2018-05-01

Image quality in B-mode ultrasound is important as it reflects the diagnostic accuracy and diagnostic information provided during clinical scanning. Quality assurance programs for B-mode ultrasound systems/components are comprised of initial quality acceptance testing and subsequent regularly scheduled quality control testing. The importance of quality assurance programs for B-mode ultrasound image quality using ultrasound phantoms is well documented in the human medical and medical physics literature. The purpose of this prospective, cross-sectional, survey study was to determine the prevalence and methodology of quality acceptance testing and quality control testing of image quality for ultrasound system/components among veterinary sonographers. An online electronic survey was sent to 1497 members of veterinary imaging organizations: the American College of Veterinary Radiology, the Veterinary Ultrasound Society, and the European Association of Veterinary Diagnostic Imaging, and a total of 167 responses were received. The results showed that the percentages of veterinary sonographers performing quality acceptance testing and quality control testing are 42% (64/151; 95% confidence interval 34-52%) and 26% (40/156: 95% confidence interval 19-33%) respectively. Of the respondents who claimed to have quality acceptance testing or quality control testing of image quality in place for their ultrasound system/components, 0% have performed quality acceptance testing or quality control testing correctly (quality acceptance testing 95% confidence interval: 0-6%, quality control testing 95% confidence interval: 0-11%). Further education and guidelines are recommended for veterinary sonographers in the area of quality acceptance testing and quality control testing for B-mode ultrasound equipment/components. © 2018 American College of Veterinary Radiology.
Minimum training requirement in ultrasound imaging of peripheral arterial disease.

Science.gov (United States)

Eiberg, J P; Hansen, M A; Grønvall Rasmussen, J B; Schroeder, T V

2008-09-01

To demonstrate the minimum training requirement when performing ultrasound of peripheral arterial disease. Prospective and blinded comparative study. 100 limbs in 100 consecutive patients suffering from peripheral arterial disease, 74% suffering critical limb ischemia, were enrolled during a 9 months period. One physician with limited ultrasound experience performed all the ultrasound examinations of the arteries of the most symptomatic limb. Before enrolling any patients 15 duplex ultrasound examinations were performed supervised by an experienced vascular technologist. All patients had a digital subtraction arteriography performed by an experienced vascular radiologist, unaware of the ultrasound result. The number of insufficiently insonated segments (non-diagnostic segments) was significantly reduced during the study; from 9% among the initial 50 limbs to 2% among the last 50 limbs (Pultrasound and arteriography from the initial 50 patients (overall Kappa=0.66, (95%-CI: 0.60-0.72); supragenicular Kappa=0.73 (95%-CI: 0.64-0.82); infragenicular Kappa=0.61 (95%-CI: 0.54-0.69)) to the last 50 patients (overall Kappa=0.66 (95%-CI: 0.60-0.72), supragenicular Kappa=0.67 (95%-CI: 0.57-0.76); infragenicular Kappa=0.66 (95%-CI: 0.58-0.73)). The minimum training requirement in ultrasound imaging of peripheral arterial disease appears to be less than 50 ultrasound examinations (probably only 15 examinations) for the supragenicular segments and 100 examinations for the infragenicular segments.
Visualization of ultrasound induced cavitation bubbles using the synchrotron x-ray Analyzer Based Imaging technique

International Nuclear Information System (INIS)

Izadifar, Zahra; Izadifar, Mohammad; Izadifar, Zohreh; Chapman, Dean; Belev, George

2014-01-01

Observing cavitation bubbles deep within tissue is very difficult. The development of a method for probing cavitation, irrespective of its location in tissues, would improve the efficiency and application of ultrasound in the clinic. A synchrotron x-ray imaging technique, which is capable of detecting cavitation bubbles induced in water by a sonochemistry system, is reported here; this could possibly be extended to the study of therapeutic ultrasound in tissues. The two different x-ray imaging techniques of Analyzer Based Imaging (ABI) and phase contrast imaging (PCI) were examined in order to detect ultrasound induced cavitation bubbles. Cavitation was not observed by PCI, however it was detectable with ABI. Acoustic cavitation was imaged at six different acoustic power levels and six different locations through the acoustic beam in water at a fixed power level. The results indicate the potential utility of this technique for cavitation studies in tissues, but it is time consuming. This may be improved by optimizing the imaging method. (paper)
Visualization of ultrasound induced cavitation bubbles using the synchrotron x-ray Analyzer Based Imaging technique.

Science.gov (United States)

Izadifar, Zahra; Belev, George; Izadifar, Mohammad; Izadifar, Zohreh; Chapman, Dean

2014-12-07

Observing cavitation bubbles deep within tissue is very difficult. The development of a method for probing cavitation, irrespective of its location in tissues, would improve the efficiency and application of ultrasound in the clinic. A synchrotron x-ray imaging technique, which is capable of detecting cavitation bubbles induced in water by a sonochemistry system, is reported here; this could possibly be extended to the study of therapeutic ultrasound in tissues. The two different x-ray imaging techniques of Analyzer Based Imaging (ABI) and phase contrast imaging (PCI) were examined in order to detect ultrasound induced cavitation bubbles. Cavitation was not observed by PCI, however it was detectable with ABI. Acoustic cavitation was imaged at six different acoustic power levels and six different locations through the acoustic beam in water at a fixed power level. The results indicate the potential utility of this technique for cavitation studies in tissues, but it is time consuming. This may be improved by optimizing the imaging method.
Development of an Anthropomorphic Breast Phantom for Combined PET, B-Mode Ultrasound and Elastographic Imaging

Science.gov (United States)

Dang, Jun; Frisch, Benjamin; Lasaygues, Philippe; Zhang, Dachun; Tavernier, Stefaan; Felix, Nicolas; Lecoq, Paul; Auffray, Etiennette; Varela, Joao; Mensah, Serge; Wan, Mingxi

2011-06-01

Combining the advantages of different imaging modalities leads to improved clinical results. For example, ultrasound provides good real-time structural information without any radiation and PET provides sensitive functional information. For the ongoing ClearPEM-Sonic project combining ultrasound and PET for breast imaging, we developed a dual-modality PET/Ultrasound (US) phantom. The phantom reproduces the acoustic and elastic properties of human breast tissue and allows labeling the different tissues in the phantom with different concentrations of FDG. The phantom was imaged with a whole-body PET/CT and with the Supersonic Imagine Aixplorer system. This system allows both B-mode US and shear wave elastographic imaging. US elastography is a new imaging method for displaying the tissue elasticity distribution. It was shown to be useful in breast imaging. We also tested the phantom with static elastography. A 6D magnetic positioning system allows fusing the images obtained with the two modalities. ClearPEM-Sonic is a project of the Crystal Clear Collaboration and the European Centre for Research on Medical Imaging (CERIMED).
Imaging in gynecological disease (9): clinical and ultrasound characteristics of tubal cancer.

Science.gov (United States)

Ludovisi, M; De Blasis, I; Virgilio, B; Fischerova, D; Franchi, D; Pascual, M A; Savelli, L; Epstein, E; Van Holsbeke, C; Guerriero, S; Czekierdowski, A; Zannoni, G; Scambia, G; Jurkovic, D; Rossi, A; Timmerman, D; Valentin, L; Testa, A C

2014-03-01

To describe clinical history and ultrasound findings in patients with tubal carcinoma. Patients with a histological diagnosis of tubal cancer who had undergone preoperative ultrasound examination were identified from the databases of 13 ultrasound centers. The tumors were described by the principal investigator at each contributing center on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In addition, three authors reviewed together all available digital ultrasound images and described them using subjective evaluation of gray-scale and color Doppler ultrasound findings. We identified 79 women with a histological diagnosis of primary tubal cancer, 70 of whom (89%) had serous carcinomas and 46 (58%) of whom presented at FIGO stage III. Forty-nine (62%) women were asymptomatic (incidental finding), whilst the remaining 30 complained of abdominal bloating or pain. Fifty-three (67%) tumors were described as solid at ultrasound examination, 14 (18%) as multilocular solid, 10 (13%) as unilocular solid and two (3%) as unilocular. No tumor was described as a multilocular mass. Most tumors (70/79, 89%) were moderately or very well vascularized on color or power Doppler ultrasound. Normal ovarian tissue was identified adjacent to the tumor in 51% (39/77) of cases. Three types of ultrasound appearance were identified as being typical of tubal carcinoma using pattern recognition: a sausage-shaped cystic structure with solid tissue protruding into it like a papillary projection (11/62, 18%); a sausage-shaped cystic structure with a large solid component filling part of the cyst cavity (13/62, 21%); an ovoid or oblong completely solid mass (36/62, 58%). A well vascularized ovoid or sausage-shaped structure, either completely solid or with large solid component(s) in the pelvis, should raise the suspicion of tubal cancer, especially if normal
Prostate Ultrasound

Medline Plus

Full Text Available ... Z Ultrasound - Prostate Ultrasound of the prostate uses sound waves to produce pictures of a man’s prostate ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...
Ultrasound -- Pelvis

Science.gov (United States)

... endometrial polyps fibroids cancer, especially in patients with abnormal uterine bleeding Some physicians also use 3-D ultrasound or ... Obstetric Ultrasound Ultrasound - Prostate Kidney and Bladder Stones Abnormal Vaginal Bleeding Ovarian Cancer Images related to Ultrasound - Pelvis Sponsored ...
Advanced 3-D Ultrasound Imaging: 3-D Synthetic Aperture Imaging using Fully Addressed and Row-Column Addressed 2-D Transducer Arrays

DEFF Research Database (Denmark)

Bouzari, Hamed

the important diagnostic information in a noninvasive manner. Diagnostic and therapeutic decisions often require accurate estimates of e.g., organ, cyst, or tumor volumes. 3-D ultrasound imaging can provide these measurements without relying on the geometrical assumptions and operator-dependent skills involved...... is one of the factors for the widespread use of ultrasound imaging. The high price tag on the high quality 3-D scanners is limiting their market share. Row-column addressing of 2-D transducer arrays is a low cost alternative to fully addressed 2-D arrays, for 3-D ultrasound imaging. Using row....... Based on a set of acoustical measurements the center frequency, bandwidth, surface pressure, sensitivity, and acoustical cross-talks were evaluated and discussed. The imaging quality assessments were carried out based on Field II simulations as well as phantom measurements. Moreover, an analysis...
APES Beamforming Applied to Medical Ultrasound Imaging

DEFF Research Database (Denmark)

Blomberg, Ann E. A.; Holfort, Iben Kraglund; Austeng, Andreas

2009-01-01

Recently, adaptive beamformers have been introduced to medical ultrasound imaging. The primary focus has been on the minimum variance (MV) (or Capon) beamformer. This work investigates an alternative but closely related beamformer, the Amplitude and Phase Estimation (APES) beamformer. APES offers...... added robustness at the expense of a slightly lower resolution. The purpose of this study was to evaluate the performance of the APES beamformer on medical imaging data, since correct amplitude estimation often is just as important as spatial resolution. In our simulations we have used a 3.5 MHz, 96...... element linear transducer array. When imaging two closely spaced point targets, APES displays nearly the same resolution as the MV, and at the same time improved amplitude control. When imaging cysts in speckle, APES offers speckle statistics similar to that of the DAS, without the need for temporal...

Some links on this page may take you to non-federal websites. Their policies may differ from this site.