WorldWideScience

Sample records for 3-d ultrasound guidance

  1. 3D transrectal ultrasound prostate biopsy using a mechanical imaging and needle-guidance system

    Bax, Jeffrey; Cool, Derek; Gardi, Lori; Montreuil, Jacques; Gil, Elena; Bluvol, Jeremy; Knight, Kerry; Smith, David; Romagnoli, Cesare; Fenster, Aaron

    2008-03-01

    Prostate biopsy procedures are generally limited to 2D transrectal ultrasound (TRUS) imaging for biopsy needle guidance. This limitation results in needle position ambiguity and an insufficient record of biopsy core locations in cases of prostate re-biopsy. We have developed a multi-jointed mechanical device that supports a commercially available TRUS probe with an integrated needle guide for precision prostate biopsy. The device is fixed at the base, allowing the joints to be manually manipulated while fully supporting its weight throughout its full range of motion. Means are provided to track the needle trajectory and display this trajectory on a corresponding TRUS image. This allows the physician to aim the needle-guide at predefined targets within the prostate, providing true 3D navigation. The tracker has been designed for use with several end-fired transducers that can be rotated about the longitudinal axis of the probe to generate 3D images. The tracker reduces the variability associated with conventional hand-held probes, while preserving user familiarity and procedural workflow. In a prostate phantom, biopsy needles were guided to within 2 mm of their targets, and the 3D location of the biopsy core was accurate to within 3 mm. The 3D navigation system is validated in the presence of prostate motion in a preliminary patient study.

  2. Development of 3D ultrasound needle guidance for high-dose-rate interstitial brachytherapy of gynaecological cancers

    Rodgers, J.; Tessier, D.; D'Souza, D.; Leung, E.; Hajdok, G.; Fenster, A.

    2016-04-01

    High-dose-rate (HDR) interstitial brachytherapy is often included in standard-of-care for gynaecological cancers. Needles are currently inserted through a perineal template without any standard real-time imaging modality to assist needle guidance, causing physicians to rely on pre-operative imaging, clinical examination, and experience. While two-dimensional (2D) ultrasound (US) is sometimes used for real-time guidance, visualization of needle placement and depth is difficult and subject to variability and inaccuracy in 2D images. The close proximity to critical organs, in particular the rectum and bladder, can lead to serious complications. We have developed a three-dimensional (3D) transrectal US system and are investigating its use for intra-operative visualization of needle positions used in HDR gynaecological brachytherapy. As a proof-of-concept, four patients were imaged with post-insertion 3D US and x-ray CT. Using software developed in our laboratory, manual rigid registration of the two modalities was performed based on the perineal template's vaginal cylinder. The needle tip and a second point along the needle path were identified for each needle visible in US. The difference between modalities in the needle trajectory and needle tip position was calculated for each identified needle. For the 60 needles placed, the mean trajectory difference was 3.23 +/- 1.65° across the 53 visible needle paths and the mean difference in needle tip position was 3.89 +/- 1.92 mm across the 48 visible needles tips. Based on the preliminary results, 3D transrectal US shows potential for the development of a 3D US-based needle guidance system for interstitial gynaecological brachytherapy.

  3. Investigation of variability in image acquisition and contouring during 3D ultrasound guidance for partial breast irradiation

    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

  4. Advanced 3-D Ultrasound Imaging

    Rasmussen, Morten Fischer

    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...... and removes the need to integrate custom made electronics into the probe. A downside of row-column addressing 2-D arrays is the creation of secondary temporal lobes, or ghost echoes, in the point spread function. In the second part of the scientific contributions, row-column addressing of 2-D arrays...... was investigated. An analysis of how the ghost echoes can be attenuated was presented.Attenuating the ghost echoes were shown to be achieved by minimizing the first derivative of the apodization function. In the literature, a circular symmetric apodization function was proposed. A new apodization layout...

  5. 3D ultrafast ultrasound imaging in vivo

    Very high frame rate ultrasound imaging has recently allowed for the extension of the applications of echography to new fields of study such as the functional imaging of the brain, cardiac electrophysiology, and the quantitative imaging of the intrinsic mechanical properties of tumors, to name a few, non-invasively and in real time. In this study, we present the first implementation of Ultrafast Ultrasound Imaging in 3D based on the use of either diverging or plane waves emanating from a sparse virtual array located behind the probe. It achieves high contrast and resolution while maintaining imaging rates of thousands of volumes per second. A customized portable ultrasound system was developed to sample 1024 independent channels and to drive a 32  ×  32 matrix-array probe. Its ability to track in 3D transient phenomena occurring in the millisecond range within a single ultrafast acquisition was demonstrated for 3D Shear-Wave Imaging, 3D Ultrafast Doppler Imaging, and, finally, 3D Ultrafast combined Tissue and Flow Doppler Imaging. The propagation of shear waves was tracked in a phantom and used to characterize its stiffness. 3D Ultrafast Doppler was used to obtain 3D maps of Pulsed Doppler, Color Doppler, and Power Doppler quantities in a single acquisition and revealed, at thousands of volumes per second, the complex 3D flow patterns occurring in the ventricles of the human heart during an entire cardiac cycle, as well as the 3D in vivo interaction of blood flow and wall motion during the pulse wave in the carotid at the bifurcation. This study demonstrates the potential of 3D Ultrafast Ultrasound Imaging for the 3D mapping of stiffness, tissue motion, and flow in humans in vivo and promises new clinical applications of ultrasound with reduced intra—and inter-observer variability. (fast track communication)

  6. Towards real-time 3D ultrasound planning and personalized 3D printing for breast HDR brachytherapy treatment

    Two different end-to-end procedures were tested for real-time planning in breast HDR brachytherapy treatment. Both methods are using a 3D ultrasound (3DUS) system and a freehand catheter optimization algorithm. They were found fast and efficient. We demonstrated a proof-of-concept approach for personalized real-time guidance and planning to breast HDR brachytherapy treatments

  7. Probe Trajectory Interpolation for 3D Reconstruction of Freehand Ultrasound

    Coupé, Pierrick; Hellier, Pierre; Morandi, Xavier; Barillot, Christian

    2007-01-01

    Three-dimensional (3D) Freehand ultrasound uses the acquisition of non parallel B-scans localized in 3D by a tracking system (optic, mechanical or magnetic). Using the positions of the irregularly spaced B-scans, a regular 3D lattice volume can be reconstructed, to which conventional 3D computer vision algorithms (registration and segmentation) can be applied. This paper presents a new 3D reconstruction method which explicitly accounts for the probe trajectory. Experiments were conducted on p...

  8. 3D Flow reconstruction using ultrasound PIV

    Poelma, C.; Mari, J. M.; Foin, N.; Tang, M.-X.; Krams, R; Caro, C.G.; Weinberg, P.D.; Westerweel, J.

    2009-01-01

    Ultrasound particle image velocimetry (PIV) can be used to obtain velocity fields in non-transparent geometries and/or fluids. In the current study, we use this technique to document the flow in a curved tube, using ultrasound contrast bubbles as flow tracer particles. The performance of the technique is first tested in a straight tube, with both steady laminar and pulsatile flows. Both experiments confirm that the technique is capable of reliable measurements. A number of adaptations are int...

  9. Segmentation of Right Ventricle in 3D Ultrasound Recordings

    Engås, Asbjørn Breivik

    2008-01-01

    This thesis presents segmentation of the right ventricle of the heart in real-time tracking of 3D ultrasound recordings. A simple deformable model for the right ventricle is developed based on statistical data from manual segmentations, and the model has been tested out in a set of 3D ultrasound recordings and compared to manually segmented right ventricular volumes. The manual segmentation method with volume approximation is also developed. The segmentation tests on the recordings are pe...

  10. Ultrasound image guidance of cardiac interventions

    Peters, Terry M.; Pace, Danielle F.; Lang, Pencilla; Guiraudon, Gérard M.; Jones, Douglas L.; Linte, Cristian A.

    2011-03-01

    Surgical procedures often have the unfortunate side-effect of causing the patient significant trauma while accessing the target site. Indeed, in some cases the trauma inflicted on the patient during access to the target greatly exceeds that caused by performing the therapy. Heart disease has traditionally been treated surgically using open chest techniques with the patient being placed "on pump" - i.e. their circulation being maintained by a cardio-pulmonary bypass or "heart-lung" machine. Recently, techniques have been developed for performing minimally invasive interventions on the heart, obviating the formerly invasive procedures. These new approaches rely on pre-operative images, combined with real-time images acquired during the procedure. Our approach is to register intra-operative images to the patient, and use a navigation system that combines intra-operative ultrasound with virtual models of instrumentation that has been introduced into the chamber through the heart wall. This paper illustrates the problems associated with traditional ultrasound guidance, and reviews the state of the art in real-time 3D cardiac ultrasound technology. In addition, it discusses the implementation of an image-guided intervention platform that integrates real-time ultrasound with a virtual reality environment, bringing together the pre-operative anatomy derived from MRI or CT, representations of tracked instrumentation inside the heart chamber, and the intra-operatively acquired ultrasound images.

  11. Reproducibility of Two 3-D Ultrasound Carotid Plaque Quantification Methods

    Graebe, Martin; Entrekin, Robert; Collet-Billon, Antoine; Harrison, Gerard; Sillesen, Henrik

    2014-01-01

    -sectional, 2-D freehand sweep and a mechanical 3-D ultrasound investigation of 62 carotid artery plaques is reported with intra-class correlation coefficients (with 95% confidence intervals). Inter-observer agreement was 0.60 (0.29-0.77) for the freehand method and 0.89 (0.83-0.93) for the mechanical 3-D...

  12. Multi-resolution Gabor wavelet feature extraction for needle detection in 3D ultrasound

    Pourtaherian, Arash; Zinger, Svitlana; Mihajlovic, Nenad; de With, Peter H. N.; Huang, Jinfeng; Ng, Gary C.; Korsten, Hendrikus H. M.

    2015-12-01

    Ultrasound imaging is employed for needle guidance in various minimally invasive procedures such as biopsy guidance, regional anesthesia and brachytherapy. Unfortunately, a needle guidance using 2D ultrasound is very challenging, due to a poor needle visibility and a limited field of view. Nowadays, 3D ultrasound systems are available and more widely used. Consequently, with an appropriate 3D image-based needle detection technique, needle guidance and interventions may significantly be improved and simplified. In this paper, we present a multi-resolution Gabor transformation for an automated and reliable extraction of the needle-like structures in a 3D ultrasound volume. We study and identify the best combination of the Gabor wavelet frequencies. High precision in detecting the needle voxels leads to a robust and accurate localization of the needle for the intervention support. Evaluation in several ex-vivo cases shows that the multi-resolution analysis significantly improves the precision of the needle voxel detection from 0.23 to 0.32 at a high recall rate of 0.75 (gain 40%), where a better robustness and confidence were confirmed in the practical experiments.

  13. Chest wall segmentation in automated 3D breast ultrasound scans.

    Tan, Tao; Platel, Bram; Mann, Ritse M; Huisman, Henkjan; Karssemeijer, Nico

    2013-12-01

    In this paper, we present an automatic method to segment the chest wall in automated 3D breast ultrasound images. Determining the location of the chest wall in automated 3D breast ultrasound images is necessary in computer-aided detection systems to remove automatically detected cancer candidates beyond the chest wall and it can be of great help for inter- and intra-modal image registration. We show that the visible part of the chest wall in an automated 3D breast ultrasound image can be accurately modeled by a cylinder. We fit the surface of our cylinder model to a set of automatically detected rib-surface points. The detection of the rib-surface points is done by a classifier using features representing local image intensity patterns and presence of rib shadows. Due to attenuation of the ultrasound signal, a clear shadow is visible behind the ribs. Evaluation of our segmentation method is done by computing the distance of manually annotated rib points to the surface of the automatically detected chest wall. We examined the performance on images obtained with the two most common 3D breast ultrasound devices in the market. In a dataset of 142 images, the average mean distance of the annotated points to the segmented chest wall was 5.59 ± 3.08 mm. PMID:23273891

  14. [An integrated segmentation method for 3D ultrasound carotid artery].

    Yang, Xin; Wu, Huihui; Liu, Yang; Xu, Hongwei; Liang, Huageng; Cai, Wenjuan; Fang, Mengjie; Wang, Yujie

    2013-07-01

    An integrated segmentation method for 3D ultrasound carotid artery was proposed. 3D ultrasound image was sliced into transverse, coronal and sagittal 2D images on the carotid bifurcation point. Then, the three images were processed respectively, and the carotid artery contours and thickness were obtained finally. This paper tries to overcome the disadvantages of current computer aided diagnosis method, such as high computational complexity, easily introduced subjective errors et al. The proposed method could get the carotid artery overall information rapidly, accurately and completely. It could be transplanted into clinical usage for atherosclerosis diagnosis and prevention. PMID:24195385

  15. 3D/3D registration of coronary CTA and biplane XA reconstructions for improved image guidance

    Dibildox, Gerardo, E-mail: g.dibildox@erasmusmc.nl; Baka, Nora; Walsum, Theo van [Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Punt, Mark; Aben, Jean-Paul [Pie Medical Imaging, 6227 AJ Maastricht (Netherlands); Schultz, Carl [Department of Cardiology, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Niessen, Wiro [Quantitative Imaging Group, Faculty of Applied Sciences, Delft University of Technology, 2628 CJ Delft, The Netherlands and Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands)

    2014-09-15

    Purpose: The authors aim to improve image guidance during percutaneous coronary interventions of chronic total occlusions (CTO) by providing information obtained from computed tomography angiography (CTA) to the cardiac interventionist. To this end, the authors investigate a method to register a 3D CTA model to biplane reconstructions. Methods: The authors developed a method for registering preoperative coronary CTA with intraoperative biplane x-ray angiography (XA) images via 3D models of the coronary arteries. The models are extracted from the CTA and biplane XA images, and are temporally aligned based on CTA reconstruction phase and XA ECG signals. Rigid spatial alignment is achieved with a robust probabilistic point set registration approach using Gaussian mixture models (GMMs). This approach is extended by including orientation in the Gaussian mixtures and by weighting bifurcation points. The method is evaluated on retrospectively acquired coronary CTA datasets of 23 CTO patients for which biplane XA images are available. Results: The Gaussian mixture model approach achieved a median registration accuracy of 1.7 mm. The extended GMM approach including orientation was not significantly different (P > 0.1) but did improve robustness with regards to the initialization of the 3D models. Conclusions: The authors demonstrated that the GMM approach can effectively be applied to register CTA to biplane XA images for the purpose of improving image guidance in percutaneous coronary interventions.

  16. The Application of Ultrasound in 3D Bio-Printing.

    Zhou, Yufeng

    2016-01-01

    Three-dimensional (3D) bioprinting is an emerging and promising technology in tissue engineering to construct tissues and organs for implantation. Alignment of self-assembly cell spheroids that are used as bioink could be very accurate after droplet ejection from bioprinter. Complex and heterogeneous tissue structures could be built using rapid additive manufacture technology and multiple cell lines. Effective vascularization in the engineered tissue samples is critical in any clinical application. In this review paper, the current technologies and processing steps (such as printing, preparation of bioink, cross-linking, tissue fusion and maturation) in 3D bio-printing are introduced, and their specifications are compared with each other. In addition, the application of ultrasound in this novel field is also introduced. Cells experience acoustic radiation force in ultrasound standing wave field (USWF) and then accumulate at the pressure node at low acoustic pressure. Formation of cell spheroids by this method is within minutes with uniform size and homogeneous cell distribution. Neovessel formation from USWF-induced endothelial cell spheroids is significant. Low-intensity ultrasound could enhance the proliferation and differentiation of stem cells. Its use is at low cost and compatible with current bioreactor. In summary, ultrasound application in 3D bio-printing may solve some challenges and enhance the outcomes. PMID:27164066

  17. The Application of Ultrasound in 3D Bio-Printing

    Yufeng Zhou

    2016-05-01

    Full Text Available Three-dimensional (3D bioprinting is an emerging and promising technology in tissue engineering to construct tissues and organs for implantation. Alignment of self-assembly cell spheroids that are used as bioink could be very accurate after droplet ejection from bioprinter. Complex and heterogeneous tissue structures could be built using rapid additive manufacture technology and multiple cell lines. Effective vascularization in the engineered tissue samples is critical in any clinical application. In this review paper, the current technologies and processing steps (such as printing, preparation of bioink, cross-linking, tissue fusion and maturation in 3D bio-printing are introduced, and their specifications are compared with each other. In addition, the application of ultrasound in this novel field is also introduced. Cells experience acoustic radiation force in ultrasound standing wave field (USWF and then accumulate at the pressure node at low acoustic pressure. Formation of cell spheroids by this method is within minutes with uniform size and homogeneous cell distribution. Neovessel formation from USWF-induced endothelial cell spheroids is significant. Low-intensity ultrasound could enhance the proliferation and differentiation of stem cells. Its use is at low cost and compatible with current bioreactor. In summary, ultrasound application in 3D bio-printing may solve some challenges and enhance the outcomes.

  18. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    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.

  19. Benchmarking of state-of-the-art needle detection algorithms in 3D ultrasound data volumes

    Pourtaherian, Arash; Zinger, Svitlana; de With, Peter H. N.; Korsten, Hendrikus H. M.; Mihajlovic, Nenad

    2015-03-01

    Ultrasound-guided needle interventions are widely practiced in medical diagnostics and therapy, i.e. for biopsy guidance, regional anesthesia or for brachytherapy. Needle guidance using 2D ultrasound can be very challenging due to the poor needle visibility and the limited field of view. Since 3D ultrasound transducers are becoming more widely used, needle guidance can be improved and simplified with appropriate computer-aided analyses. In this paper, we compare two state-of-the-art 3D needle detection techniques: a technique based on line filtering from literature and a system employing Gabor transformation. Both algorithms utilize supervised classification to pre-select candidate needle voxels in the volume and then fit a model of the needle on the selected voxels. The major differences between the two approaches are in extracting the feature vectors for classification and selecting the criterion for fitting. We evaluate the performance of the two techniques using manually-annotated ground truth in several ex-vivo situations of different complexities, containing three different needle types with various insertion angles. This extensive evaluation provides better understanding on the limitations and advantages of each technique under different acquisition conditions, which is leading to the development of improved techniques for more reliable and accurate localization. Benchmarking results that the Gabor features are better capable of distinguishing the needle voxels in all datasets. Moreover, it is shown that the complete processing chain of the Gabor-based method outperforms the line filtering in accuracy and stability of the detection results.

  20. Development of a 3D ultrasound-guided prostate biopsy system

    Cool, Derek; Sherebrin, Shi; Izawa, Jonathan; Fenster, Aaron

    2007-03-01

    Biopsy of the prostate using ultrasound guidance is the clinical gold standard for diagnosis of prostate adenocarinoma. However, because early stage tumors are rarely visible under US, the procedure carries high false-negative rates and often patients require multiple biopsies before cancer is detected. To improve cancer detection, it is imperative that throughout the biopsy procedure, physicians know where they are within the prostate and where they have sampled during prior biopsies. The current biopsy procedure is limited to using only 2D ultrasound images to find and record target biopsy core sample sites. This information leaves ambiguity as the physician tries to interpret the 2D information and apply it to their 3D workspace. We have developed a 3D ultrasound-guided prostate biopsy system that provides 3D intra-biopsy information to physicians for needle guidance and biopsy location recording. The system is designed to conform to the workflow of the current prostate biopsy procedure, making it easier for clinical integration. In this paper, we describe the system design and validate its accuracy by performing an in vitro biopsy procedure on US/CT multi-modal patient-specific prostate phantoms. A clinical sextant biopsy was performed by a urologist on the phantoms and the 3D models of the prostates were generated with volume errors less than 4% and mean boundary errors of less than 1 mm. Using the 3D biopsy system, needles were guided to within 1.36 +/- 0.83 mm of 3D targets and the position of the biopsy sites were accurately localized to 1.06 +/- 0.89 mm for the two prostates.

  1. Breast tumour visualization using 3D quantitative ultrasound methods

    Gangeh, Mehrdad J.; Raheem, Abdul; Tadayyon, Hadi; Liu, Simon; Hadizad, Farnoosh; Czarnota, Gregory J.

    2016-04-01

    Breast cancer is one of the most common cancer types accounting for 29% of all cancer cases. Early detection and treatment has a crucial impact on improving the survival of affected patients. Ultrasound (US) is non-ionizing, portable, inexpensive, and real-time imaging modality for screening and quantifying breast cancer. Due to these attractive attributes, the last decade has witnessed many studies on using quantitative ultrasound (QUS) methods in tissue characterization. However, these studies have mainly been limited to 2-D QUS methods using hand-held US (HHUS) scanners. With the availability of automated breast ultrasound (ABUS) technology, this study is the first to develop 3-D QUS methods for the ABUS visualization of breast tumours. Using an ABUS system, unlike the manual 2-D HHUS device, the whole patient's breast was scanned in an automated manner. The acquired frames were subsequently examined and a region of interest (ROI) was selected in each frame where tumour was identified. Standard 2-D QUS methods were used to compute spectral and backscatter coefficient (BSC) parametric maps on the selected ROIs. Next, the computed 2-D parameters were mapped to a Cartesian 3-D space, interpolated, and rendered to provide a transparent color-coded visualization of the entire breast tumour. Such 3-D visualization can potentially be used for further analysis of the breast tumours in terms of their size and extension. Moreover, the 3-D volumetric scans can be used for tissue characterization and the categorization of breast tumours as benign or malignant by quantifying the computed parametric maps over the whole tumour volume.

  2. Fully automatic plaque segmentation in 3-D carotid ultrasound images.

    Cheng, Jieyu; Li, He; Xiao, Feng; Fenster, Aaron; Zhang, Xuming; He, Xiaoling; Li, Ling; Ding, Mingyue

    2013-12-01

    Automatic segmentation of the carotid plaques from ultrasound images has been shown to be an important task for monitoring progression and regression of carotid atherosclerosis. Considering the complex structure and heterogeneity of plaques, a fully automatic segmentation method based on media-adventitia and lumen-intima boundary priors is proposed. This method combines image intensity with structure information in both initialization and a level-set evolution process. Algorithm accuracy was examined on the common carotid artery part of 26 3-D carotid ultrasound images (34 plaques ranging in volume from 2.5 to 456 mm(3)) by comparing the results of our algorithm with manual segmentations of two experts. Evaluation results indicated that the algorithm yielded total plaque volume (TPV) differences of -5.3 ± 12.7 and -8.5 ± 13.8 mm(3) and absolute TPV differences of 9.9 ± 9.5 and 11.8 ± 11.1 mm(3). Moreover, high correlation coefficients in generating TPV (0.993 and 0.992) between algorithm results and both sets of manual results were obtained. The automatic method provides a reliable way to segment carotid plaque in 3-D ultrasound images and can be used in clinical practice to estimate plaque measurements for management of carotid atherosclerosis. PMID:24063959

  3. Glasses for 3D ultrasound computer tomography: phase compensation

    Zapf, M.; Hopp, T.; Ruiter, N. V.

    2016-03-01

    Ultrasound Computer Tomography (USCT), developed at KIT, is a promising new imaging system for breast cancer diagnosis, and was successfully tested in a pilot study. The 3D USCT II prototype consists of several hundreds of ultrasound (US) transducers on a semi-ellipsoidal aperture. Spherical waves are sequentially emitted by individual transducers and received in parallel by many transducers. Reflectivity volumes are reconstructed by synthetic aperture focusing (SAFT). However, straight forward SAFT imaging leads to blurred images due to system imperfections. We present an extension of a previously proposed approach to enhance the images. This approach includes additional a priori information and system characteristics. Now spatial phase compensation was included. The approach was evaluated with a simulation and clinical data sets. An increase in the image quality was observed and quantitatively measured by SNR and other metrics.

  4. Framework for 3D TransRectal Ultrasound

    Mozer, Pierre; Chevreau, G; Daanen, Vincent; Moreau-Gaudry, Alexandre; Troccaz, Jocelyne

    2008-01-01

    Prostate biopsies are mainly performed under 2D TransRectal UltraSound (TRUS) control by sampling the prostate according to a predefined pattern. In case of first biopsies, this pattern follows a random systematic plan. Sometimes, repeat biopsies can be needed to target regions unsampled by previous biopsies or resample critical regions (for example in case of cancer expectant management or previous prostatic intraepithelial neoplasia findings). From a clinical point of view, it could be useful to control the 3D spatial distribution of theses biopsies inside the prostate. Modern 3D-TRUS probes allow acquiring high-quality volumes of the prostate in few seconds. We developed a framework to track the prostate in 3D TRUS images. It means that if one acquires a reference volume at the beginning of the session and another during each biopsy, it is possible to determine the relationship between the prostate in the reference and the others volumes by aligning images. We used this tool to evaluate the ability of a si...

  5. Advanced 3-D Ultrasound Imaging.:3-D Synthetic Aperture Imaging and Row-column Addressing of 2-D Transducer Arrays

    Rasmussen, Morten Fischer; Jensen, Jørgen Arendt

    2014-01-01

    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 clinic...

  6. 3D ultrasound computer tomography: update from a clinical study

    Hopp, T.; Zapf, M.; Kretzek, E.; Henrich, J.; Tukalo, A.; Gemmeke, H.; Kaiser, C.; Knaudt, J.; Ruiter, N. V.

    2016-04-01

    Ultrasound Computer Tomography (USCT) is a promising new imaging method for breast cancer diagnosis. We developed a 3D USCT system and tested it in a pilot study with encouraging results: 3D USCT was able to depict two carcinomas, which were present in contrast enhanced MRI volumes serving as ground truth. To overcome severe differences in the breast shape, an image registration was applied. We analyzed the correlation between average sound speed in the breast and the breast density estimated from segmented MRIs and found a positive correlation with R=0.70. Based on the results of the pilot study we now carry out a successive clinical study with 200 patients. For this we integrated our reconstruction methods and image post-processing into a comprehensive workflow. It includes a dedicated DICOM viewer for interactive assessment of fused USCT images. A new preview mode now allows intuitive and faster patient positioning. We updated the USCT system to decrease the data acquisition time by approximately factor two and to increase the penetration depth of the breast into the USCT aperture by 1 cm. Furthermore the compute-intensive reflectivity reconstruction was considerably accelerated, now allowing a sub-millimeter volume reconstruction in approximately 16 minutes. The updates made it possible to successfully image first patients in our ongoing clinical study.

  7. Model fitting using RANSAC for surgical tool localization in 3-D ultrasound images.

    Uhercík, Marián; Kybic, Jan; Liebgott, Hervé; Cachard, Christian

    2010-08-01

    Ultrasound guidance is used for many surgical interventions such as biopsy and electrode insertion. We present a method to localize a thin surgical tool such as a biopsy needle or a microelectrode in a 3-D ultrasound image. The proposed method starts with thresholding and model fitting using random sample consensus for robust localization of the axis. Subsequent local optimization refines its position. Two different tool image models are presented: one is simple and fast and the second uses learned a priori information about the tool's voxel intensities and the background. Finally, the tip of the tool is localized by finding an intensity drop along the axis. The simulation study shows that our algorithm can localize the tool at nearly real-time speed, even using a MATLAB implementation, with accuracy better than 1 mm. In an experimental comparison with several alternative localization methods, our method appears to be the fastest and the most robust one. We also show the results on real 3-D ultrasound data from a PVA cryogel phantom, turkey breast, and breast biopsy. PMID:20483680

  8. 3D Rotational X-Ray guidance for surgical interventions

    Kraats, Everine Brenda van de

    2005-01-01

    The research described in this thesis is aimed at increasing the accuracy and decreasing the invasiveness of surgical procedures, with a focus on spine procedures, by using a combination of multi-modality images, computer-assisted navigation, intraoperative 3D rotational X-ray (3DRX) imaging, and mi

  9. Three dimensional (3d) transverse oscillation vector velocity ultrasound imaging

    2013-01-01

    An ultrasound imaging system (300) includes a transducer array (302) with a two- dimensional array of transducer elements configured to transmit an ultrasound signal and receive echoes, transmit circuitry (304) configured to control the transducer array to transmit the ultrasound signal so as to...... the same received set of two dimensional echoes form part of the imaging system...

  10. Sonographic measurement of thyroid gland volume: A comparison of 2D and 3D ultrasound

    Ying, Michael [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)]. E-mail: ormying@polyu.edu.hk; Sin Manhong [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Pang, Shuk-fan [Department of Optometry and Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)

    2005-11-01

    Aims: This study was undertaken to investigate the inter-observer reproducibility of 2D and 3D ultrasound in the measurement of thyroid gland volume. The symmetry of thyroid lobes in healthy subjects was also investigated. Materials and methods: The volume of the left and right lobes of the thyroid gland was measured in 20 healthy subjects (10 men and 10 women) using 2D and 3D ultrasound. On 2D ultrasound, the thyroid lobe volume was calculated by ellipsoid equation (volume = {pi}/6 x craniocaudal x mediolateral x anteroposterior dimensions), whereas 3D ultrasound volumetric measurements were performed with a 3D add-on system. In each subject, the thyroid gland was scanned by two operators to investigate inter-observer variability. Results: There was a moderate agreement between 2D and 3D ultrasound in the measurement of thyroid volume (r = 0.77). 3D ultrasound (90%) had a higher inter-observer reproducibility than 2D ultrasound (85%) in the measurements. About 74% of healthy subjects had the right thyroid lobe larger than the left lobe. Conclusion: 3D ultrasound is useful in the measurement of thyroid volume with a higher reproducibility than 2D ultrasound. Asymmetry of thyroid lobes was noted in healthy subjects.

  11. Sonographic measurement of thyroid gland volume: A comparison of 2D and 3D ultrasound

    Aims: This study was undertaken to investigate the inter-observer reproducibility of 2D and 3D ultrasound in the measurement of thyroid gland volume. The symmetry of thyroid lobes in healthy subjects was also investigated. Materials and methods: The volume of the left and right lobes of the thyroid gland was measured in 20 healthy subjects (10 men and 10 women) using 2D and 3D ultrasound. On 2D ultrasound, the thyroid lobe volume was calculated by ellipsoid equation (volume = π/6 x craniocaudal x mediolateral x anteroposterior dimensions), whereas 3D ultrasound volumetric measurements were performed with a 3D add-on system. In each subject, the thyroid gland was scanned by two operators to investigate inter-observer variability. Results: There was a moderate agreement between 2D and 3D ultrasound in the measurement of thyroid volume (r = 0.77). 3D ultrasound (90%) had a higher inter-observer reproducibility than 2D ultrasound (85%) in the measurements. About 74% of healthy subjects had the right thyroid lobe larger than the left lobe. Conclusion: 3D ultrasound is useful in the measurement of thyroid volume with a higher reproducibility than 2D ultrasound. Asymmetry of thyroid lobes was noted in healthy subjects

  12. Low-Power Receive-Electronics for a Miniature 3D Ultrasound Probe

    Yu, Z.

    2012-01-01

    This thesis describes the design of a front-end application-specific integrated circuit (ASIC), which will be put into the tip of a miniature ultrasound probe for 3D Trans-Esophageal Echocardiography (TEE). To enable 3D TEE, a matrix piezoelectric ultrasound transducer with more than 2000 elements w

  13. Contrast-enhanced 3D ultrasound in the radiofrequency ablation of liver tumors

    Edward Leen; Senthil Kumar; Shahid A Khan; Gavin Low; Keh Oon Ong; Paul Tait; Mike Averkiou

    2009-01-01

    Liver metastases and hepatocellular carcinomas are two of the most common causes of cancer deaths in the world. Radiofrequency ablation (RFA) is a well recognized, effective and minimally invasive means of treating malignant hepatic tumors. This article describes the use of contrast-enhanced 3D ultrasound (CE-3DUS) in the staging, targeting and followup of patients with liver tumors undergoing RFA. In particular, its value in the management of large hepatic lesions will be illustrated. Current limitations of CE-3DUS and future developments in the technique will also be discussed. In summary, CE-3DUS is useful in the RFA of liver tumors with improved detection and display of occult lesions and recurrence, in the assessment of lesional geometry and orientation for a more accurate planning and guidance of multiple RFA needle electrodes in large tumors and in the evaluation of residual or recurrent disease within the immediate and/or subsequent follow-up periods.

  14. Segmentation of Carotid Arteries from 3D and 4D Ultrasound Images

    Mattsson, Per; Eriksson, Andreas

    2002-01-01

    This thesis presents a 3D semi-automatic segmentation technique for extracting the lumen surface of the Carotid arteries including the bifurcation from 3D and 4D ultrasound examinations. Ultrasound images are inherently noisy. Therefore, to aid the inspection of the acquired data an adaptive edge preserving filtering technique is used to reduce the general high noise level. The segmentation process starts with edge detection with a recursive and separable 3D Monga-Deriche-Canny operator. To r...

  15. Prenatal 3D Ultrasound Diagnostics in Cleidocranial Dysplasia

    Hermann, NV; Hove, HD; Jørgensen, C;

    2009-01-01

    A 34-year-old Caucasian woman with cleidocranial dysplasia (CCD) and a known family history of CCD was referred for an ultrasound examination in the first trimester of her second pregnancy. Molecular genetic analysis of the RUNX2 gene was non-informative. A routine 2D ultrasound examination carried...

  16. Towards 3D ultrasound image based soft tissue tracking: a transrectal ultrasound prostate image alignment system

    Baumann, Michael; Daanen, Vincent; Troccaz, Jocelyne

    2007-01-01

    The emergence of real-time 3D ultrasound (US) makes it possible to consider image-based tracking of subcutaneous soft tissue targets for computer guided diagnosis and therapy. We propose a 3D transrectal US based tracking system for precise prostate biopsy sample localisation. The aim is to improve sample distribution, to enable targeting of unsampled regions for repeated biopsies, and to make post-interventional quality controls possible. Since the patient is not immobilized, since the prostate is mobile and due to the fact that probe movements are only constrained by the rectum during biopsy acquisition, the tracking system must be able to estimate rigid transformations that are beyond the capture range of common image similarity measures. We propose a fast and robust multi-resolution attribute-vector registration approach that combines global and local optimization methods to solve this problem. Global optimization is performed on a probe movement model that reduces the dimensionality of the search space a...

  17. A compact mechatronic system for 3D ultrasound guided prostate interventions

    Purpose: Ultrasound imaging has improved the treatment of prostate cancer by producing increasingly higher quality images and influencing sophisticated targeting procedures for the insertion of radioactive seeds during brachytherapy. However, it is critical that the needles be placed accurately within the prostate to deliver the therapy to the planned location and avoid complications of damaging surrounding tissues. Methods: The authors have developed a compact mechatronic system, as well as an effective method for guiding and controlling the insertion of transperineal needles into the prostate. This system has been designed to allow guidance of a needle obliquely in 3D space into the prostate, thereby reducing pubic arch interference. The choice of needle trajectory and location in the prostate can be adjusted manually or with computer control. Results: To validate the system, a series of experiments were performed on phantoms. The 3D scan of the string phantom produced minimal geometric error, which was less than 0.4 mm. Needle guidance accuracy tests in agar prostate phantoms showed that the mean error of bead placement was less then 1.6 mm along parallel needle paths that were within 1.2 mm of the intended target and 1 deg. from the preplanned trajectory. At oblique angles of up to 15 deg. relative to the probe axis, beads were placed to within 3.0 mm along a trajectory that were within 2.0 mm of the target with an angular error less than 2 deg. Conclusions: By combining 3D TRUS imaging system to a needle tracking linkage, this system should improve the physician's ability to target and accurately guide a needle to selected targets without the need for the computer to directly manipulate and insert the needle. This would be beneficial as the physician has complete control of the system and can safely maneuver the needle guide around obstacles such as previously placed needles.

  18. Evaluation of low-dose limits in 3D-2D rigid registration for surgical guidance

    Uneri, A.; Wang, A. S.; Otake, Y.; Kleinszig, G.; Vogt, S.; Khanna, A. J.; Gallia, G. L.; Gokaslan, Z. L.; Siewerdsen, J. H.

    2014-09-01

    An algorithm for intensity-based 3D-2D registration of CT and C-arm fluoroscopy is evaluated for use in surgical guidance, specifically considering the low-dose limits of the fluoroscopic x-ray projections. The registration method is based on a framework using the covariance matrix adaptation evolution strategy (CMA-ES) to identify the 3D patient pose that maximizes the gradient information similarity metric. Registration performance was evaluated in an anthropomorphic head phantom emulating intracranial neurosurgery, using target registration error (TRE) to characterize accuracy and robustness in terms of 95% confidence upper bound in comparison to that of an infrared surgical tracking system. Three clinical scenarios were considered: (1) single-view image + guidance, wherein a single x-ray projection is used for visualization and 3D-2D guidance; (2) dual-view image + guidance, wherein one projection is acquired for visualization, combined with a second (lower-dose) projection acquired at a different C-arm angle for 3D-2D guidance; and (3) dual-view guidance, wherein both projections are acquired at low dose for the purpose of 3D-2D guidance alone (not visualization). In each case, registration accuracy was evaluated as a function of the entrance surface dose associated with the projection view(s). Results indicate that images acquired at a dose as low as 4 μGy (approximately one-tenth the dose of a typical fluoroscopic frame) were sufficient to provide TRE comparable or superior to that of conventional surgical tracking, allowing 3D-2D guidance at a level of dose that is at most 10% greater than conventional fluoroscopy (scenario #2) and potentially reducing the dose to approximately 20% of the level in a conventional fluoroscopically guided procedure (scenario #3).

  19. CISUS: an integrated 3D ultrasound system for IGT using a modular tracking API

    Boctor, Emad M.; Viswanathan, Anand; Pieper, Steve; Choti, Michael A.; Taylor, Russell H.; Kikinis, Ron; Fichtinger, Gabor

    2004-05-01

    Ultrasound has become popular in clinical/surgical applications, both as the primary image guidance modality and also in conjunction with other modalities like CT or MRI. Three dimensional ultrasound (3DUS) systems have also demonstrated usefulness in image-guided therapy (IGT). At the same time, however, current lack of open-source and open-architecture multi-modal medical visualization systems prevents 3DUS from fulfilling its potential. Several stand-alone 3DUS systems, like Stradx or In-Vivo exist today. Although these systems have been found to be useful in real clinical setting, it is difficult to augment their functionality and integrate them in versatile IGT systems. To address these limitations, a robotic/freehand 3DUS open environment (CISUS) is being integrated into the 3D Slicer, an open-source research tool developed for medical image analysis and surgical planning. In addition, the system capitalizes on generic application programming interfaces (APIs) for tracking devices and robotic control. The resulting platform-independent open-source system may serve as a valuable tool to the image guided surgery community. Other researchers could straightforwardly integrate the generic CISUS system along with other functionalities (i.e. dual view visualization, registration, real-time tracking, segmentation, etc) to rapidly create their medical/surgical applications. Our current driving clinical application is robotically assisted and freehand 3DUS-guided liver ablation, which is fully being integrated under the CISUS-3D Slicer. Initial functionality and pre-clinical feasibility are demonstrated on phantom and ex-vivo animal models.

  20. Ultrasound 3D positioning system for surgical instruments

    Tatar, F.

    2006-01-01

    This thesis presents various aspects regarding the development of an ultrasound sensor systems for use in laparoscopic intervention. The accuracy achieved after using compensation technique for air flow disturbances or temperature variations remains in a convenient range of 200µm. Considering this

  1. A framework for human spine imaging using a freehand 3D ultrasound system

    Purnama, Ketut E.; Wilkinson, Michael H.F.; Veldhuizen, Albert G.; Ooijen, van Peter M.A.; Lubbers, Jaap; Burgerhof, Johannes G.M.; Sardjono, Tri A.; Verkerke, Gijsbertus J.

    2010-01-01

    The use of 3D ultrasound imaging to follow the progression of scoliosis, i.e., a 3D deformation of the spine, is described. Unlike other current examination modalities, in particular based on X-ray, its non-detrimental effect enables it to be used frequently to follow the progression of scoliosis wh

  2. Optimizing ultrasound detection for sensitive 3D photoacoustic breast tomography

    Xia, Wenfeng

    2013-01-01

    The standard modality for breast cancer detection is X-ray imaging. Diagnosis is performed after the triple assessment of X-ray mammography assisted by ultrasonog- raphy and biopsy. Magnetic resonance imaging (MRI) is sometimes used in specific problem solving such as contradictory results are obtained from X-ray and ultrasound images. X-ray mammography is capable of producing 2D projection images with a high spatial resolution. However, X-ray mammography besides possessing ionizing hazards, ...

  3. Ultrasound 3D positioning system for surgical instruments

    Tatar, F.

    2006-01-01

    This thesis presents various aspects regarding the development of an ultrasound sensor systems for use in laparoscopic intervention. The accuracy achieved after using compensation technique for air flow disturbances or temperature variations remains in a convenient range of 200µm. Considering this high accuracy, the flexibility and the ergonomics achieved for this system, the final device may be adapted very easily and used also in other microsurgery applications.

  4. Py3DFreeHandUS: A PURE PYTHON LIBRARY FOR 3D VOXEL-ARRAY RECONSTRUCTION BY USING 3D FREEHAND ULTRASOUND

    Monari, Davide; Cenni, Francesco; Aertbeliën, Erwin; Desloovere, Kaat

    2014-01-01

    INTRODUCTION and AIM 3D Freehand ultrasound (3DUS) is a technique that combines ultrasound images and position + orientation sensors (POS) with the aim to reconstruct large 3D anatomical parts. However, the few existing applications for applying this technique have at least one of the following disadvantages: i) not open-source; ii) only supporting data streams from a limited number of ultrasound or POS devices; iii) they are written in low-level languages such as C++, making rapid develop...

  5. The effect of object speed and direction on the performance of 3D speckle tracking using a 3D swept-volume ultrasound probe.

    Harris, EJ; Miller, NR; Bamber, JC; Symonds-Tayler, JR; Evans, PM

    2011-01-01

    Three-dimensional (3D) soft tissue tracking using 3D ultrasound is of interest for monitoring organ motion during therapy. Previously we demonstrated feature tracking of respiration-induced liver motion in vivo using a 3D swept-volume ultrasound probe. The aim of this study was to investigate how object speed affects the accuracy of tracking ultrasonic speckle in the absence of any structural information, which mimics the situation in homogenous tissue for motion in the azimuthal and elevatio...

  6. 3D temperature field reconstruction using ultrasound sensing system

    Liu, Yuqian; Ma, Tong; Cao, Chengyu; Wang, Xingwei

    2016-04-01

    3D temperature field reconstruction is of practical interest to the power, transportation and aviation industries and it also opens up opportunities for real time control or optimization of high temperature fluid or combustion process. In our paper, a new distributed optical fiber sensing system consisting of a series of elements will be used to generate and receive acoustic signals. This system is the first active temperature field sensing system that features the advantages of the optical fiber sensors (distributed sensing capability) and the acoustic sensors (non-contact measurement). Signals along multiple paths will be measured simultaneously enabled by a code division multiple access (CDMA) technique. Then a proposed Gaussian Radial Basis Functions (GRBF)-based approach can approximate the temperature field as a finite summation of space-dependent basis functions and time-dependent coefficients. The travel time of the acoustic signals depends on the temperature of the media. On this basis, the Gaussian functions are integrated along a number of paths which are determined by the number and distribution of sensors. The inversion problem to estimate the unknown parameters of the Gaussian functions can be solved with the measured times-of-flight (ToF) of acoustic waves and the length of propagation paths using the recursive least square method (RLS). The simulation results show an approximation error less than 2% in 2D and 5% in 3D respectively. It demonstrates the availability and efficiency of our proposed 3D temperature field reconstruction mechanism.

  7. Development and evaluation of a semiautomatic 3D segmentation technique of the carotid arteries from 3D ultrasound images

    Gill, Jeremy D.; Ladak, Hanif M.; Steinman, David A.; Fenster, Aaron

    1999-05-01

    In this paper, we report on a semi-automatic approach to segmentation of carotid arteries from 3D ultrasound (US) images. Our method uses a deformable model which first is rapidly inflated to approximately find the boundary of the artery, then is further deformed using image-based forces to better localize the boundary. An operator is required to initialize the model by selecting a position in the 3D US image, which is within the carotid vessel. Since the choice of position is user-defined, and therefore arbitrary, there is an inherent variability in the position and shape of the final segmented boundary. We have assessed the performance of our segmentation method by examining the local variability in boundary shape as the initial selected position is varied in a freehand 3D US image of a human carotid bifurcation. Our results indicate that high variability in boundary position occurs in regions where either the segmented boundary is highly curved, or the 3D US image has poorly defined vessel edges.

  8. Towards enabling ultrasound guidance in cervical cancer high-dose-rate brachytherapy

    Wong, Adrian; Sojoudia, Samira; Gaudet, Marc; Yap, Wan Wan; Chang, Silvia D.; Abolmaesumi, Purang; Aquino-Parsons, Christina; Moradi, Mehdi

    2014-03-01

    MRI and Computed Tomography (CT) are used in image-based solutions for guiding High Dose Rate (HDR) brachytherapy treatment of cervical cancer. MRI is costly and CT exposes the patients to ionizing radiation. Ultrasound, on the other hand, is affordable and safe. The long-term goal of our work is to enable the use of multiparametric ultrasound imaging in image-guided HDR for cervical cancer. In this paper, we report the development of enabling technology for ultrasound guidance and tissue typing. We report a system to obtain the 3D freehand transabdominal ultrasound RF signals and B-mode images of the uterus, and a method for registration of ultrasound to MRI. MRI and 3D ultrasound images of the female pelvis were registered by contouring the uterus in the two modalities, creating a surface model, followed by rigid and B-spline deformable registration. The resulting transformation was used to map the location of the tumor from the T2-weighted MRI to ultrasound images and to determine cancerous and normal areas in ultrasound. B-mode images show a contrast for cancer vs. normal tissue. Our study shows the potential and the challenges of ultrasound imaging in guiding cervical cancer treatments.

  9. 4D ultrasound and 3D MRI registration of beating heart

    To realize intra-cardiac surgery without cardio-pulmonary bypass, a medical imaging technique with both high image quality and data acquisition rate that is fast enough to follow heart beat movements is required. In this research, we proposed a method that utilized the image quality of MRI and the speed of ultrasound. We developed a 4D image reconstruction method using image registration of 3D MRI and 4D ultrasound images. The registration method consists of rigid registration between 3D MRI and 3D ultrasound with the same heart beat phase, and non-rigid registration between 3D ultrasound images from different heart beat phases. Non-rigid registration was performed with B-spline based registration using variable spring model. In phantom experiment using balloon phantom, registration accuracy was less than 2 mm for total heart volume variation range of 10%. We applied our registration method on 3D MRI and 4D ultrasound images of a volunteer's beating heart data and confirmed through visual observation that heart beat pattern was well reproduced. (orig.)

  10. Advantages and disadvantages of 3D ultrasound of thyroid nodules including thin slice volume rendering

    Slapa Rafal

    2011-01-01

    Full Text Available Abstract Background The purpose of this study was to assess the advantages and disadvantages of 3D gray-scale and power Doppler ultrasound, including thin slice volume rendering (TSVR, applied for evaluation of thyroid nodules. Methods The retrospective evaluation by two observers of volumes of 71 thyroid nodules (55 benign, 16 cancers was performed using a new TSVR technique. Dedicated 4D ultrasound scanner with an automatic 6-12 MHz 4D probe was used. Statistical analysis was performed with Stata v. 8.2. Results Multiple logistic regression analysis demonstrated that independent risk factors of thyroid cancers identified by 3D ultrasound include: (a ill-defined borders of the nodule on MPR presentation, (b a lobulated shape of the nodule in the c-plane and (c a density of central vessels in the nodule within the minimal or maximal ranges. Combination of features provided sensitivity 100% and specificity 60-69% for thyroid cancer. Calcification/microcalcification-like echogenic foci on 3D ultrasound proved not to be a risk factor of thyroid cancer. Storage of the 3D data of the whole nodules enabled subsequent evaluation of new parameters and with new rendering algorithms. Conclusions Our results indicate that 3D ultrasound is a practical and reproducible method for the evaluation of thyroid nodules. 3D ultrasound stores volumes comprising the whole lesion or organ. Future detailed evaluations of the data are possible, looking for features that were not fully appreciated at the time of collection or applying new algorithms for volume rendering in order to gain important information. Three-dimensional ultrasound data could be included in thyroid cancer databases. Further multicenter large scale studies are warranted.

  11. Automated 3D ultrasound image segmentation for assistant diagnosis of breast cancer

    Wang, Yuxin; Gu, Peng; Lee, Won-Mean; Roubidoux, Marilyn A.; Du, Sidan; Yuan, Jie; Wang, Xueding; Carson, Paul L.

    2016-04-01

    Segmentation of an ultrasound image into functional tissues is of great importance to clinical diagnosis of breast cancer. However, many studies are found to segment only the mass of interest and not all major tissues. Differences and inconsistencies in ultrasound interpretation call for an automated segmentation method to make results operator-independent. Furthermore, manual segmentation of entire three-dimensional (3D) ultrasound volumes is time-consuming, resource-intensive, and clinically impractical. Here, we propose an automated algorithm to segment 3D ultrasound volumes into three major tissue types: cyst/mass, fatty tissue, and fibro-glandular tissue. To test its efficacy and consistency, the proposed automated method was employed on a database of 21 cases of whole breast ultrasound. Experimental results show that our proposed method not only distinguishes fat and non-fat tissues correctly, but performs well in classifying cyst/mass. Comparison of density assessment between the automated method and manual segmentation demonstrates good consistency with an accuracy of 85.7%. Quantitative comparison of corresponding tissue volumes, which uses overlap ratio, gives an average similarity of 74.54%, consistent with values seen in MRI brain segmentations. Thus, our proposed method exhibits great potential as an automated approach to segment 3D whole breast ultrasound volumes into functionally distinct tissues that may help to correct ultrasound speed of sound aberrations and assist in density based prognosis of breast cancer.

  12. Optimizing nonrigid registration performance between volumetric true 3D ultrasound images in image-guided neurosurgery

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

    2011-03-01

    Compensating for brain shift as surgery progresses is important to ensure sufficient accuracy in patient-to-image registration in the operating room (OR) for reliable neuronavigation. Ultrasound has emerged as an important and practical imaging technique for brain shift compensation either by itself or through computational modeling that estimates whole-brain deformation. Using volumetric true 3D ultrasound (3DUS), it is possible to nonrigidly (e.g., based on B-splines) register two temporally different 3DUS images directly to generate feature displacement maps for data assimilation in the biomechanical model. Because of a large amount of data and number of degrees-of-freedom (DOFs) involved, however, a significant computational cost may be required that can adversely influence the clinical feasibility of the technique for efficiently generating model-updated MR (uMR) in the OR. This paper parametrically investigates three B-splines registration parameters and their influence on the computational cost and registration accuracy: number of grid nodes along each direction, floating image volume down-sampling rate, and number of iterations. A simulated rigid body displacement field was employed as a ground-truth against which the accuracy of displacements generated from the B-splines nonrigid registration was compared. A set of optimal parameters was then determined empirically that result in a registration computational cost of less than 1 min and a sub-millimetric accuracy in displacement measurement. These resulting parameters were further applied to a clinical surgery case to demonstrate their practical use. Our results indicate that the optimal set of parameters result in sufficient accuracy and computational efficiency in model computation, which is important for future application of the overall biomechanical modeling to generate uMR for image-guidance in the OR.

  13. Development of 3D ultrasound techniques for carotid artery disease assessment and monitoring

    Quantitative measurements of carotid plaque burden are used to monitor patients and evaluate established interventions as well as new treatment options. Three-dimensional ultrasound (3D US) techniques were developed to noninvasively monitor the progression of carotid artery disease in both symptomatic and asymptomatic patients. Three-dimensional carotid US images were acquired and reconstructed, and methods for quantitative assessment were developed. The measurement of intima-media thickness (IMT) based on two-dimensional ultrasound (2D US) images was extended to a 3D vessel-wall-plus- plaque thickness (VWT), obtained by computing the distance between the carotid wall and lumen surfaces on a point-by-point basis. VWT measurements were superimposed on the arterial wall to produce 3D VWT maps. VWT changes were determined by comparing the 3D VWT maps obtained at two different time points. To facilitate the visualization and interpretation of the VWT and VWT-Change maps, a technique to flatten these maps was developed. Carotid remodeling involving changes in both arterial wall and plaque thickness was assessed with VWT maps obtained from in vivo 3D ultrasound images. 3D carotid ultrasound image evaluation with VWT mapping provides a feasible means for the analysis of plaque burden volumes and changes. (orig.)

  14. 3D freehand ultrasound for medical assistance in diagnosis and treatment of breast cancer: preliminary results

    Torres, Fabian; Fanti, Zian; Arambula Cosío, F.

    2013-11-01

    Image-guided interventions allow the physician to have a better planning and visualization of a procedure. 3D freehand ultrasound is a non-invasive and low-cost imaging tool that can be used to assist medical procedures. This tool can be used in the diagnosis and treatment of breast cancer. There are common medical practices that involve large needles to obtain an accurate diagnosis and treatment of breast cancer. In this study we propose the use of 3D freehand ultrasound for planning and guiding such procedures as core needle biopsy and radiofrequency ablation. The proposed system will help the physician to identify the lesion area, using image-processing techniques in the 3D freehand ultrasound images, and guide the needle to this area using the information of position and orientation of the surgical tools. We think that this system can upgrade the accuracy and efficiency of these procedures.

  15. Computer-Assisted Hepatocellular Carcinoma Ablation Planning Based on 3-D Ultrasound Imaging.

    Li, Kai; Su, Zhongzhen; Xu, Erjiao; Guan, Peishan; Li, Liu-Jun; Zheng, Rongqin

    2016-08-01

    To evaluate computer-assisted hepatocellular carcinoma (HCC) ablation planning based on 3-D ultrasound, 3-D ultrasound images of 60 HCC lesions from 58 patients were obtained and transferred to a research toolkit. Compared with virtual manual ablation planning (MAP), virtual computer-assisted ablation planning (CAP) consumed less time and needle insertion numbers and exhibited a higher rate of complete tumor coverage and lower rate of critical structure injury. In MAP, junior operators used less time, but had more critical structure injury than senior operators. For large lesions, CAP performed better than MAP. For lesions near critical structures, CAP resulted in better outcomes than MAP. Compared with MAP, CAP based on 3-D ultrasound imaging was more effective and achieved a higher rate of complete tumor coverage and a lower rate of critical structure injury; it is especially useful for junior operators and with large lesions, and lesions near critical structures. PMID:27126243

  16. Mapping cardiac fiber orientations from high-resolution DTI to high-frequency 3D ultrasound

    Qin, Xulei; Wang, Silun; Shen, Ming; Zhang, Xiaodong; Wagner, Mary B.; Fei, Baowei

    2014-03-01

    The orientation of cardiac fibers affects the anatomical, mechanical, and electrophysiological properties of the heart. Although echocardiography is the most common imaging modality in clinical cardiac examination, it can only provide the cardiac geometry or motion information without cardiac fiber orientations. If the patient's cardiac fiber orientations can be mapped to his/her echocardiography images in clinical examinations, it may provide quantitative measures for diagnosis, personalized modeling, and image-guided cardiac therapies. Therefore, this project addresses the feasibility of mapping personalized cardiac fiber orientations to three-dimensional (3D) ultrasound image volumes. First, the geometry of the heart extracted from the MRI is translated to 3D ultrasound by rigid and deformable registration. Deformation fields between both geometries from MRI and ultrasound are obtained after registration. Three different deformable registration methods were utilized for the MRI-ultrasound registration. Finally, the cardiac fiber orientations imaged by DTI are mapped to ultrasound volumes based on the extracted deformation fields. Moreover, this study also demonstrated the ability to simulate electricity activations during the cardiac resynchronization therapy (CRT) process. The proposed method has been validated in two rat hearts and three canine hearts. After MRI/ultrasound image registration, the Dice similarity scores were more than 90% and the corresponding target errors were less than 0.25 mm. This proposed approach can provide cardiac fiber orientations to ultrasound images and can have a variety of potential applications in cardiac imaging.

  17. Validity Study of Vertebral Rotation Measurement Using 3-D Ultrasound in Adolescent Idiopathic Scoliosis.

    Wang, Qian; Li, Meng; Lou, Edmond H M; Chu, Winnie C W; Lam, Tsz-Ping; Cheng, Jack C Y; Wong, Man-Sang

    2016-07-01

    This study aimed to assess the validity of 3-D ultrasound measurements on the vertebral rotation of adolescent idiopathic scoliosis (AIS) under clinical settings. Thirty curves (mean Cobb angle: 21.7° ± 15.9°) from 16 patients with AIS were recruited. 3-D ultrasound and magnetic resonance imaging scans were performed at the supine position. Each of the two raters measured the apical vertebral rotation using the center of laminae (COL) method in the 3-D ultrasound images and the Aaro-Dahlborn method in the magnetic resonance images. The intra- and inter-reliability of the COL method was demonstrated by the intra-class correlation coefficient (ICC) (both [2, K] >0.9, p correlation was found (r > 0.9, p < 0.05). These results validated the proposed 3-D ultrasound method in the measurements of vertebral rotation in the patients with AIS. PMID:27083978

  18. GPU-Based Block-Wise Nonlocal Means Denoising for 3D Ultrasound Images

    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.

  19. Integrated endoscope for real-time 3D ultrasound imaging and hyperthermia: feasibility study.

    Pua, Eric C; Qiu, Yupeng; Smith, S W

    2007-01-01

    The goal of this research is to determine the feasibility of using a single endoscopic probe for the combined purpose of real-time 3D (RT3D) ultrasound imaging of a target organ and the delivery of ultrasound therapy to facilitate the absorption of compounds for cancer treatment. Recent research in ultrasound therapy has shown that ultrasound-mediated drug delivery improves absorption of treatments for prostate, cervical and esophageal cancer. The ability to combine ultrasound hyperthermia and 3D imaging could improve visualization and targeting of cancerous tissues. In this study, numerical modeling and experimental measurements were developed to determine the feasibility of combined therapy and imaging with a 1 cm diameter endoscopic RT3D probe with 504 transmitters and 252 receive channels. This device operates at 5 MHz and has a 6.3 mm x 6.3 mm aperture to produce real time 3D pyramidal scans of 60-120 degrees incorporating 64 x 64 = 4096 image lines at 30 volumes/sec interleaved with a 3D steerable therapy beam. A finite-element mesh was constructed with over 128,000 elements in LS-DYNA to simulate the induced temperature rise from our transducer with a 3 cm deep focus in tissue. Quarter-symmetry of the transducer was used to reduce mesh size and computation time. Based on intensity values calculated in Field II using the transducer's array geometry, a minimum I(SPTA) of 3.6 W/cm2 is required from our endoscope probe in order to induce a temperature rise of 4 degrees C within five minutes. Experimental measurements of the array's power output capabilities were conducted using a PVDF hydrophone placed 3 cm away from the face of the transducer in a watertank. Using a PDA14 Signatec data acquisition board to capture full volumes of transmitted ultrasound data, it was determined that the probe can presently maintain intensity values up to 2.4 W/cm2 over indefinite times for therapeutic applications combined with intermittent 3D scanning to maintain targeting

  20. Can ultrasound guidance reduce the risk of pneumothorax following thoracentesis?

    Alessandro Perazzo

    2014-01-01

    Full Text Available OBJECTIVE: Thoracentesis is one of the bedside procedures most commonly associated with iatrogenic complications, particularly pneumothorax. Various risk factors for complications associated with thoracentesis have recently been identified, including an inexperienced operator; an inadequate or inexperienced support team; the lack of a standardized protocol; and the lack of ultrasound guidance. We sought to determine whether ultrasound-guided thoracentesis can reduce the risk of pneumothorax and improve outcomes (fewer procedures without fluid removal and greater volumes of fluid removed during the procedures. In our comparison of thoracentesis with and without ultrasound guidance, all procedures were performed by a team of expert pulmonologists, using the same standardized protocol in both conditions. METHODS: A total of 160 participants were randomly allocated to undergo thoracentesis with or without ultrasound guidance (n = 80 per group. The primary outcome was pneumothorax following thoracentesis. Secondary outcomes included the number of procedures without fluid removal and the volume of fluid drained during the procedure. RESULTS: Pneumothorax occurred in 1 of the 80 patients who underwent ultrasound-guided thoracentesis and in 10 of the 80 patients who underwent thoracentesis without ultrasound guidance, the difference being statistically significant (p = 0.009. Fluid was removed in 79 of the 80 procedures performed with ultrasound guidance and in 72 of the 80 procedures performed without it. The mean volume of fluid drained was larger during the former than during the latter (960 ± 500 mL vs. 770 ± 480 mL, the difference being statistically significant (p = 0.03. CONCLUSIONS: Ultrasound guidance increases the yield of thoracentesis and reduces the risk of post-procedure pneumothorax. (Chinese Clinical Trial Registry identifier: ChiCTR-TRC-12002174 [http://www.chictr.org/en/

  1. 3D Simulation of Ultrasound in the Ultra-Distal Human Radius

    Kaufman, Jonathan J.; Luo, Gangming; Siffert, Robert S.

    The overall objective of this research is to develop an ultrasonic method for non-invasive assessment of the ultradistal radius (UDR). The specific objective of this study was to examine the propagation of ultrasound through the UDR and determine the relationships between bone mass and ultrasound, as well as the ability of ultrasound to discriminate between fracture and non-fracture cases. High-resolution peripheral-QCT (HR-pQCT) images were obtained from a set of 110 subjects that were part of a larger study on osteoporosis. Twenty-three of the subjects had experienced a UDR fracture within the past 2 years; the other 87 subjects served as controls. Each 3D image was used to simulate ultrasound measurements that would result from propagation through the UDR, from its anterior to its posterior surfaces. The simulation was carried out using Wave3000 (CyberLogic, Inc., New York, USA), which solves the full 3D viscoelastic wave equation using a finite difference time domain method. Bone mineral density associated with each radius was computed for each subject, and an ultrasound parameter known as net time delay (NTD) was evaluated. NTD has been shown to be highly correlated with total bone mass in both in vitro and clinical studies. Significant correlations were found between NTD and total bone mass (R2 = 0.91, p < 0.001). The data also showed a statistically significant difference in the NTD for the fracture and non-fracture cases (i.e., a decrease in mean NTD of 14% (P < 0.001), with a t-test statistic of 3.8). The study shows that ultrasound is correlated with bone mass at the UDR, as well as with fracture incidence. Therefore ultrasound may prove useful as a simple and convenient method for non-invasive assessment of osteoporosis and fracture risk. Work is ongoing to compare the simulated ultrasound data with clinical ultrasound measurements made on the same individuals.

  2. 3D image fusion and guidance for computer-assisted bronchoscopy

    Higgins, W. E.; Rai, L.; Merritt, S. A.; Lu, K.; Linger, N. T.; Yu, K. C.

    2005-11-01

    The standard procedure for diagnosing lung cancer involves two stages. First, the physician evaluates a high-resolution three-dimensional (3D) computed-tomography (CT) chest image to produce a procedure plan. Next, the physician performs bronchoscopy on the patient, which involves navigating the the bronchoscope through the airways to planned biopsy sites. Unfortunately, the physician has no link between the 3D CT image data and the live video stream provided during bronchoscopy. In addition, these data sources differ greatly in what they physically give, and no true 3D planning tools exist for planning and guiding procedures. This makes it difficult for the physician to translate a CT-based procedure plan to the video domain of the bronchoscope. Thus, the physician must essentially perform biopsy blindly, and the skill levels between different physicians differ greatly. We describe a system that enables direct 3D CT-based procedure planning and provides direct 3D guidance during bronchoscopy. 3D CT-based information on biopsy sites is provided interactively as the physician moves the bronchoscope. Moreover, graphical information through a live fusion of the 3D CT data and bronchoscopic video is provided during the procedure. This information is coupled with a series of computer-graphics tools to give the physician a greatly augmented reality of the patient's interior anatomy during a procedure. Through a series of controlled tests and studies with human lung-cancer patients, we have found that the system not only reduces the variation in skill level between different physicians, but also increases biopsy success rate.

  3. Integrated Interventional Devices For Real Time 3D Ultrasound Imaging and Therapy

    Smith, Stephen W.; Lee, Warren; Gentry, Kenneth L.; Pua, Eric C.; Light, Edward D.

    2006-05-01

    Two recent advances have expanded the potential of medical ultrasound: the introduction of real-time 3-D ultrasound imaging with catheter, transesophageal and laparoscopic probes and the development of interventional ultrasound therapeutic systems for focused ultrasound surgery, ablation and ultrasound enhanced drug delivery. This work describes devices combining both technologies. A series of transducer probes have been designed, fabricated and tested including: 1) a 12 French side scanning catheter incorporating a 64 element matrix array for imaging at 5MHz and a piston ablation transducer operating at 10 MHz. 2) a 14 Fr forward-scanning catheter integrating a 112 element 2-D array for imaging at 5 MHz encircled by an ablation annulus operating at 10 MHz. Finite element modeling was then used to simulate catheter annular and linear phased array transducers for ablation. 3) Linear phased array transducers were built to confirm the finite element analysis at 4 and 8 MHz including a mechanically focused 86 element 9 MHz array which transmits an ISPTA of 29.3 W/cm2 and creates a lesion in 2 minutes. 4) 2-D arrays of 504 channels operating at 5 MHz have been developed for transesophageal and laparascopic 3D imaging as well as therapeutic heating. All the devices image the heart anatomy including atria, valves, septa and en face views of the pulmonary veins.

  4. Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method

    Tao, Kai, E-mail: davidtaothree@yahoo.com.cn [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Xu, Sen, E-mail: hubeixusen@163.com [Department of Radiology, General Hospital of Shenyang Military Command, 83 Wenhua Steet, Shenhe District, Shenyang 110016, Liaoning Province (China); Liu, Xiao-yan, E-mail: kk-lxy@sohu.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Liang, Jiu-long, E-mail: liangjiulong@sohu.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Qiu, Tao, E-mail: anthonyqueen@vip.sina.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Tan, Jia-nan, E-mail: tanjianan@sina.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Che, Jian-hua, E-mail: chejianhua@163.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China); Wang, Zi-hua, E-mail: rockstar520@163.com [Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016 (China)

    2012-11-15

    Objective: To introduce a useful and accurate technique for the locating and removal of small metal foreign bodies in the soft tissues. Methods: Eight patients presented with suspected small metal foreign bodies retained in the soft tissues of various body districts. Under local anesthesia, 3-6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced through three different planes around the entry point of the foreign bodies. Using these finders, the small metal FBs were confirmed under 3D CT guidance. Based on the CT findings, the soft tissues were dissected along the path of the closest needle and the FBs were easily found and removed according to the relation with the closest needle finder. Results: Eight metal foreign bodies (3 slices, 3 nails, 1 fish hook, 1 needlepoint) were successfully removed under 3D CT guidance in all patients. The procedures took between 35 min and 50 min and the operation times took between 15 min and 25 min. No complications arose after the treatment. Conclusion: 3D CT-guided technique is a good alternative for the removal of small metal foreign body retained in the soft tissues as it is relatively accurate, reliable, quick, carries a low risk of complications and can be a first-choice procedure for the extraction of small metal foreign body.

  5. Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method

    Objective: To introduce a useful and accurate technique for the locating and removal of small metal foreign bodies in the soft tissues. Methods: Eight patients presented with suspected small metal foreign bodies retained in the soft tissues of various body districts. Under local anesthesia, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced through three different planes around the entry point of the foreign bodies. Using these finders, the small metal FBs were confirmed under 3D CT guidance. Based on the CT findings, the soft tissues were dissected along the path of the closest needle and the FBs were easily found and removed according to the relation with the closest needle finder. Results: Eight metal foreign bodies (3 slices, 3 nails, 1 fish hook, 1 needlepoint) were successfully removed under 3D CT guidance in all patients. The procedures took between 35 min and 50 min and the operation times took between 15 min and 25 min. No complications arose after the treatment. Conclusion: 3D CT-guided technique is a good alternative for the removal of small metal foreign body retained in the soft tissues as it is relatively accurate, reliable, quick, carries a low risk of complications and can be a first-choice procedure for the extraction of small metal foreign body.

  6. A 3D ultrasound study of sinus tract formation in hidradenitis suppurativa

    Wortsman, Ximena; Jemec, Gregor

    2013-01-01

    characterization of the morphological changes in hidradenitis, which include the variable degrees of involvement of the hair follicles and the appearance of fluid collections and sinus tracts. Knowledge of this anatomical information may allow the identification of lesions that can benefit from medical or surgical......Imaging of hidradenitis suppurativa allows the study of both the lesion morphology and evolution. Hidradenitis lesions of different stages were studied using 3D ultrasound in a cross sectional pilot study. A total of 25 HS patients (18 female/ 7 male, aged 18-46 year-old) and 10 healthy controls (5...... female/5 male, aged 21-49 year-old) were studied. All patients were referred by dermatologists. All examinations were performed on the right axilla and compared with both controls and the skin outside the lesional areas. 3D ultrasound images demonstrated enlargement of the deepest portion of the hair...

  7. Registration of Real-Time 3-D Ultrasound to Tomographic Images of the Abdominal Aorta.

    Brekken, Reidar; Iversen, Daniel Høyer; Tangen, Geir Arne; Dahl, Torbjørn

    2016-08-01

    The purpose of this study was to develop an image-based method for registration of real-time 3-D ultrasound to computed tomography (CT) of the abdominal aorta, targeting future use in ultrasound-guided endovascular intervention. We proposed a method in which a surface model of the aortic wall was segmented from CT, and the approximate initial location of this model relative to the ultrasound volume was manually indicated. The model was iteratively transformed to automatically optimize correspondence to the ultrasound data. Feasibility was studied using data from a silicon phantom and in vivo data from a volunteer with previously acquired CT. Through visual evaluation, the ultrasound and CT data were seen to correspond well after registration. Both aortic lumen and branching arteries were well aligned. The processing was done offline, and the registration took approximately 0.2 s per ultrasound volume. The results encourage further patient studies to investigate accuracy, robustness and clinical value of the approach. PMID:27156015

  8. 3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis

    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.

  9. SURGE: Smart Ultrasound Remote Guidance Experiment

    Peterson, Sean

    2009-01-01

    Exploration-class missions lead to longer communication delays with mission control. May not always have communication capability to stream real-time ultrasound images. SURGE explores use of a "just-in-time" learning tool, called OPEL = On-Board Proficiency Enhancer Light as an aid to a hypothetical crew medical officer working autonomously.

  10. Smart Ultrasound Remote Guidance Experiment (SURGE) Preliminary Findings

    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.

  11. Accuracy assessment of high frequency 3D ultrasound for digital impression-taking of prepared teeth

    Heger, Stefan; Vollborn, Thorsten; Tinschert, Joachim; Wolfart, Stefan; Radermacher, Klaus

    2013-03-01

    Silicone based impression-taking of prepared teeth followed by plaster casting is well-established but potentially less reliable, error-prone and inefficient, particularly in combination with emerging techniques like computer aided design and manufacturing (CAD/CAM) of dental prosthesis. Intra-oral optical scanners for digital impression-taking have been introduced but until now some drawbacks still exist. Because optical waves can hardly penetrate liquids or soft-tissues, sub-gingival preparations still need to be uncovered invasively prior to scanning. High frequency ultrasound (HFUS) based micro-scanning has been recently investigated as an alternative to optical intra-oral scanning. Ultrasound is less sensitive against oral fluids and in principal able to penetrate gingiva without invasively exposing of sub-gingival preparations. Nevertheless, spatial resolution as well as digitization accuracy of an ultrasound based micro-scanning system remains a critical parameter because the ultrasound wavelength in water-like media such as gingiva is typically smaller than that of optical waves. In this contribution, the in-vitro accuracy of ultrasound based micro-scanning for tooth geometry reconstruction is being investigated and compared to its extra-oral optical counterpart. In order to increase the spatial resolution of the system, 2nd harmonic frequencies from a mechanically driven focused single element transducer were separated and corresponding 3D surface models were calculated for both fundamentals and 2nd harmonics. Measurements on phantoms, model teeth and human teeth were carried out for evaluation of spatial resolution and surface detection accuracy. Comparison of optical and ultrasound digital impression taking indicate that, in terms of accuracy, ultrasound based tooth digitization can be an alternative for optical impression-taking.

  12. Development of a Wireless and Near Real-Time 3D Ultrasound Strain Imaging System.

    Chen, Zhaohong; Chen, Yongdong; Huang, Qinghua

    2016-04-01

    Ultrasound elastography is an important medical imaging tool for characterization of lesions. In this paper, we present a wireless and near real-time 3D ultrasound strain imaging system. It uses a 3D translating device to control a commercial linear ultrasound transducer to collect pre-compression and post-compression radio-frequency (RF) echo signal frames. The RF frames are wirelessly transferred to a high-performance server via a local area network (LAN). A dynamic programming strain estimation algorithm is implemented with the compute unified device architecture (CUDA) on the graphic processing unit (GPU) in the server to calculate the strain image after receiving a pre-compression RF frame and a post-compression RF frame at the same position. Each strain image is inserted into a strain volume which can be rendered in near real-time. We take full advantage of the translating device to precisely control the probe movement and compression. The GPU-based parallel computing techniques are designed to reduce the computation time. Phantom and in vivo experimental results demonstrate that our system can generate strain volumes with good quality and display an incrementally reconstructed volume image in near real-time. PMID:26954841

  13. Smart Ultrasound Remote Guidance Experiment (SURGE)- Concept of Operations Evaluation for Using Remote Guidance Ultrasound for Planetary Space Flight

    Hurst, Victor, IV; Peterson, Sean; Garcia, Kathleen; Sargsyan, Ashot; Ebert, Douglas; Ham, David; Amponsah, David; Dulchavsky, Scott

    2010-01-01

    Introduction Use of remote guidance (RG) techniques aboard the International Space Station (ISS) has enabled astronauts to collect diagnostic-level ultrasound images. Exploration class missions will require this cohort of (typically) non-formally trained sonographers to operate with greater autonomy given the longer communication delays (2 seconds for ISS vs. >6 seconds for missions beyond the Moon) and communication blackouts. To determine the feasibility and training requirements for autonomous ultrasound image collection by non-expert ultrasound operators, ultrasound images were collected from a similar cohort using three different image collection protocols: RG only, RG with a computer-based learning tool (LT), and autonomous image collection with LT. The groups were assessed for both image quality and time to collect the images. Methods Subjects were randomized into three groups: RG only, RG with LT, and autonomous with LT. Each subject received 10 minutes of standardized training before the experiment. The subjects were tasked with making the following ultrasound assessments: 1) bone fracture and 2) focused assessment with sonography in trauma (FAST) to assess a patient s abdomen. Human factors-related questionnaire data were collected immediately after the assessments. Results The autonomous group did not out-perform the two groups that received RG. The mean time for the autonomous group to collect images was less than the RG groups, however the mean image quality for the autonomous group was less compared to both RG groups. Discussion Remote guidance continues to produce higher quality ultrasound images than autonomous ultrasound operation. This is likely due to near-instant feedback on image quality from the remote guider. Expansion in communication time delays, however, diminishes the capability to provide this feedback, thus requiring more autonomous ultrasound operation. The LT has the potential to be an excellent training and coaching component for

  14. A 3D Freehand Ultrasound System for Multi-view Reconstructions from Sparse 2D Scanning Planes

    Agurto Carla; Pattichis Marios S; Yu Honggang; Beth Goens M

    2011-01-01

    Abstract Background A significant limitation of existing 3D ultrasound systems comes from the fact that the majority of them work with fixed acquisition geometries. As a result, the users have very limited control over the geometry of the 2D scanning planes. Methods We present a low-cost and flexible ultrasound imaging system that integrates several image processing components to allow for 3D reconstructions from limited numbers of 2D image planes and multiple acoustic views. Our approach is ...

  15. Can 3D ultrasound identify trochlea dysplasia in newborns? Evaluation and applicability of a technique

    Highlights: • We evaluated a possible screening method for trochlea dysplasia. • 3D ultrasound was used to perform the measurements on standardized axial planes. • The evaluation of the technique showed comparable results to other studies. • This technique may be used as a screening technique as it is quick and easy to perform. - Abstract: Femoro-patellar dysplasia is considered as a significant risk factor of patellar instability. Different studies suggest that the shape of the trochlea is already developed in early childhood. Therefore early identification of a dysplastic configuration might be relevant information for the treating physician. An easy applicable routine screening of the trochlea is yet not available. The purpose of this study was to establish and evaluate a screening method for femoro-patellar dysplasia using 3D ultrasound. From 2012 to 2013 we prospectively imaged 160 consecutive femoro-patellar joints in 80 newborns from the 36th to 61st gestational week that underwent a routine hip sonography (Graf). All ultrasounds were performed by a pediatric radiologist with only minimal additional time to the routine hip ultrasound. In 30° flexion of the knee, axial, coronal, and sagittal reformats were used to standardize a reconstructed axial plane through the femoral condyle and the mid-patella. The sulcus angle, the lateral-to-medial facet ratio of the trochlea and the shape of the patella (Wiberg Classification) were evaluated. In all examinations reconstruction of the standardized axial plane was achieved, the mean trochlea angle was 149.1° (SD 4.9°), the lateral-to-medial facet ratio of the trochlea ratio was 1.3 (SD 0.22), and a Wiberg type I patella was found in 95% of the newborn. No statistical difference was detected between boys and girls. Using standardized reconstructions of the axial plane allows measurements to be made with lower operator dependency and higher accuracy in a short time. Therefore 3D ultrasound is an easy

  16. Can 3D ultrasound identify trochlea dysplasia in newborns? Evaluation and applicability of a technique

    Kohlhof, Hendrik, E-mail: Hendrik.Kohlhof@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Heidt, Christoph, E-mail: Christoph.heidt@kispi.uzh.ch [Department of Orthopedic Surgery, University Children' s Hospital Zurich, Steinwiesstrasse 74, 8032 Switzerland (Switzerland); Bähler, Alexandrine, E-mail: Alexandrine.baehler@insel.ch [Department of Pediatric Radiology, University Children' s Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Kohl, Sandro, E-mail: sandro.kohl@insel.ch [Department of Orthopedic Surgery, University Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Gravius, Sascha, E-mail: sascha.gravius@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Friedrich, Max J., E-mail: Max.Friedrich@ukb.uni-bonn.de [Clinic for Orthopedics and Trauma Surgery, University Hospital Bonn, Sigmund-Freud-Str. 25, 53127 Bonn (Germany); Ziebarth, Kai, E-mail: kai.ziebarth@insel.ch [Department of Orthopedic Surgery, University Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland); Stranzinger, Enno, E-mail: Enno.Stranzinger@insel.ch [Department of Pediatric Radiology, University Children' s Hospital Berne, Freiburgstrasse 18, 3010 Berne (Switzerland)

    2015-06-15

    Highlights: • We evaluated a possible screening method for trochlea dysplasia. • 3D ultrasound was used to perform the measurements on standardized axial planes. • The evaluation of the technique showed comparable results to other studies. • This technique may be used as a screening technique as it is quick and easy to perform. - Abstract: Femoro-patellar dysplasia is considered as a significant risk factor of patellar instability. Different studies suggest that the shape of the trochlea is already developed in early childhood. Therefore early identification of a dysplastic configuration might be relevant information for the treating physician. An easy applicable routine screening of the trochlea is yet not available. The purpose of this study was to establish and evaluate a screening method for femoro-patellar dysplasia using 3D ultrasound. From 2012 to 2013 we prospectively imaged 160 consecutive femoro-patellar joints in 80 newborns from the 36th to 61st gestational week that underwent a routine hip sonography (Graf). All ultrasounds were performed by a pediatric radiologist with only minimal additional time to the routine hip ultrasound. In 30° flexion of the knee, axial, coronal, and sagittal reformats were used to standardize a reconstructed axial plane through the femoral condyle and the mid-patella. The sulcus angle, the lateral-to-medial facet ratio of the trochlea and the shape of the patella (Wiberg Classification) were evaluated. In all examinations reconstruction of the standardized axial plane was achieved, the mean trochlea angle was 149.1° (SD 4.9°), the lateral-to-medial facet ratio of the trochlea ratio was 1.3 (SD 0.22), and a Wiberg type I patella was found in 95% of the newborn. No statistical difference was detected between boys and girls. Using standardized reconstructions of the axial plane allows measurements to be made with lower operator dependency and higher accuracy in a short time. Therefore 3D ultrasound is an easy

  17. Comparison of 3-D Synthetic Aperture Phased-Array Ultrasound Imaging and Parallel Beamforming

    Rasmussen, Morten Fischer; Jensen, Jørgen Arendt

    2014-01-01

    This paper demonstrates that synthetic apertureimaging (SAI) can be used to achieve real-time 3-D ultra-sound phased-array imaging. It investigates whether SAI in-creases the image quality compared with the parallel beam-forming (PB) technique for real-time 3-D imaging. Data areobtained using both...... simulations and measurements with anultrasound research scanner and a commercially available 3.5-MHz 1024-element 2-D transducer array. To limit the probecable thickness, 256 active elements are used in transmit andreceive for both techniques. The two imaging techniques weredesigned for cardiac imaging, which...... requires sequences de-signed for imaging down to 15cm of depth and a frame rateof at least 20Hz. The imaging quality of the two techniquesis investigated through simulations as a function of depth andangle. SAI improved the full-width at half-maximum (FWHM) at low steering angles by 35%, and the 20-d...

  18. 3D Elastic Registration of Ultrasound Images Based on Skeleton Feature

    LI Dan-dan; LIU Zhi-Yan; SHEN Yi

    2005-01-01

    In order to eliminate displacement and elastic deformation between images of adjacent frames in course of 3D ultrasonic image reconstruction, elastic registration based on skeleton feature was adopt in this paper. A new automatically skeleton tracking extract algorithm is presented, which can extract connected skeleton to express figure feature. Feature points of connected skeleton are extracted automatically by accounting topical curvature extreme points several times. Initial registration is processed according to barycenter of skeleton. Whereafter, elastic registration based on radial basis function are processed according to feature points of skeleton. Result of example demonstrate that according to traditional rigid registration, elastic registration based on skeleton feature retain natural difference in shape for organ's different part, and eliminate slight elastic deformation between frames caused by image obtained process simultaneously. This algorithm has a high practical value for image registration in course of 3D ultrasound image reconstruction.

  19. Carotid artery lumen segmentation in 3D free-hand ultrasound images using surface graph cuts.

    Lorza, Andrés M Arias; Carvalho, Diego D B; Petersen, Jens; van Dijk, Anouk C; van der Lugt, Aad; Niessen, Wiro J; Klein, Stefan; de Bruijne, Marleen

    2013-01-01

    We present a new approach for automated segmentation of the carotid lumen bifurcation from 3D free-hand ultrasound using a 3D surface graph cut method. The method requires only the manual selection of single seed points in the internal, external, and common carotid arteries. Subsequently, the centerline between these points is automatically traced, and the optimal lumen surface is found around the centerline using graph cuts. To refine the result, the latter process was iterated. The method was tested on twelve carotid arteries from six subjects including three patients with a moderate carotid artery stenosis. Our method successfully segmented the lumen in all cases. We obtained an average dice overlap with respect to a manual segmentation of 84% for healthy volunteers. For the patient data, we obtained a dice overlap of 66.7%. PMID:24579183

  20. Evaluation of Gastric Volumes: Comparison of 3-D Ultrasound and Magnetic Resonance Imaging.

    Buisman, Wijnand J; Mauritz, Femke A; Westerhuis, Wouter E; Gilja, Odd Helge; van der Zee, David C; van Herwaarden-Lindeboom, Maud Y A

    2016-07-01

    To investigate gastric accommodation, accurate measurements of gastric volumes are necessary. An excellent technique to measure gastric volumes is dynamic magnetic resonance imaging (MRI). Unfortunately, dynamic MRI is expensive and not always available. A new 3-D ultrasound (US) method using a matrix transducer was developed to measure gastric volumes. In this prospective study, 14 healthy volunteers underwent a dynamic MRI and a 3-D US. Gastric volumes were calculated with intra-gastric liquid content and total gastric volume. Mean postprandial liquid gastric content was 397 ± 96.5 mL. Mean volume difference was 1.0 mL with limits of agreement of -8.9 to 10.9 mL. When gastric air was taken into account, mean total gastric volume was 540 ± 115.4 mL SD. Mean volume difference was 2.3 mL with limits of agreement of -21.1 to 26.4 mL. The matrix 3-D US showed excellent agreement with dynamic MRI. Therefore matrix 3-D US is a reliable alternative to measure gastric volumes. PMID:27067418

  1. Mechanically assisted 3D ultrasound for pre-operative assessment and guiding percutaneous treatment of focal liver tumors

    Sadeghi Neshat, Hamid; Bax, Jeffery; Barker, Kevin; Gardi, Lori; Chedalavada, Jason; Kakani, Nirmal; Fenster, Aaron

    2014-03-01

    Image-guided percutaneous ablation is the standard treatment for focal liver tumors deemed inoperable and is commonly used to maintain eligibility for patients on transplant waitlists. Radiofrequency (RFA), microwave (MWA) and cryoablation technologies are all delivered via one or a number of needle-shaped probes inserted directly into the tumor. Planning is mostly based on contrast CT/MRI. While intra-procedural CT is commonly used to confirm the intended probe placement, 2D ultrasound (US) remains the main, and in some centers the only imaging modality used for needle guidance. Corresponding intraoperative 2D US with planning and other intra-procedural imaging modalities is essential for accurate needle placement. However, identification of matching features of interest among these images is often challenging given the limited field-of-view (FOV) and low quality of 2D US images. We have developed a passive tracking arm with a motorized scan-head and software tools to improve guiding capabilities of conventional US by large FOV 3D US scans that provides more anatomical landmarks that can facilitate registration of US with both planning and intra-procedural images. The tracker arm is used to scan the whole liver with a high geometrical accuracy that facilitates multi-modality landmark based image registration. Software tools are provided to assist with the segmentation of the ablation probes and tumors, find the 2D view that best shows the probe(s) from a 3D US image, and to identify the corresponding image from planning CT scans. In this paper, evaluation results from laboratory testing and a phase 1 clinical trial for planning and guiding RFA and MWA procedures using the developed system will be presented. Early clinical results show a comparable performance to intra-procedural CT that suggests 3D US as a cost-effective alternative with no side-effects in centers where CT is not available.

  2. Ultrasound as a reliable guidance system for percutaneous nephrostomy

    To determine the effectiveness and safety of ultrasound as a reliable guidance system for percutaneous nephrostomy (PCN). One hundred and fifty-three PCN were performed in 140 patients, referred from the Department of Urology and Transplantation, JPMC. Out of 140 patients, 137 had obstructive uropathy (>1 cm dilated pelvicalyceal system) of different etiologies. Three patients with ureteral rupture (non dilated pelvicalyceal system) underwent PCN for urinary diversion in the surgical ICU. The technique involved a pre procedural scan, initial renal puncture, placement of a guide wire, tract dilation and placement of 8-12 F Nephrostomy tube, entirely under ultrasound guidance. The machine used was 'Just vision' or 'Eccocee' with 3.5 MHz variable frequency convex transducer. Effectiveness in terms of successful tube placement and safety in terms of complications were observed. Out of 153 patients there were 78 males and 62 females. The minimum age of patient was 13 years while maximum age was 68 years, all (100%) patients had successful placement of PCN. Minor complications like transient gross hematuria and small perinephric collection occurred in 13 cases (8.5%) but was dealt with effectively by conservative measures. No major complications like hemorrhage, sepsis or periorgan damage were encountered in any of the patients. Ultrasound was found to be a rapid, effective, radiation-free, portable and safe imaging modality with minimum rate of complications that could be used as a reliable guidance system for critical interventions like percutaneous nephrostomies without using fluoroscopic units. (author)

  3. Active ultrasound pattern injection system (AUSPIS for interventional tool guidance.

    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.

  4. Craniosynostosis: prenatal diagnosis by 2D/3D ultrasound, magnetic resonance imaging and computed tomography.

    Helfer, Talita Micheletti; Peixoto, Alberto Borges; Tonni, Gabriele; Araujo Júnior, Edward

    2016-09-01

    Craniosynostosis is defined as the process of premature fusion of one or more of the cranial sutures. It is a common condition that occurs in about 1 to 2,000 live births. Craniosynostosis may be classified in primary or secondary. It is also classified as nonsyndromic or syndromic. According to suture commitment, craniosynostosis may affect a single suture or multiple sutures. There is a wide range of syndromes involving craniosynostosis and the most common are Apert, Pffeifer, Crouzon, Shaethre-Chotzen and Muenke syndromes. The underlying etiology of nonsyndromic craniosynostosis is unknown. Mutations in the fibroblast growth factor (FGF) signalling pathway play a crucial role in the etiology of craniosynostosis syndromes. Prenatal ultrasound`s detection rate of craniosynostosis is low. Nowadays, different methods can be applied for prenatal diagnosis of craniosynostosis, such as two-dimensional (2D) and three-dimensional (3D) ultrasound, magnetic resonance imaging (MRI), computed tomography (CT) scan and, finally, molecular diagnosis. The presence of craniosynostosis may affect the birthing process. Fetuses with craniosynostosis also have higher rates of perinatal complications. In order to avoid the risks of untreated craniosynostosis, children are usually treated surgically soon after postnatal diagnosis. PMID:27622416

  5. EXPLOITING 3D ULTRASOUND FOR FETAL DIAGNOSTIC PURPOSE THROUGH FACIAL LANDMARKING

    Enrico Vezzetti

    2014-06-01

    Full Text Available In the last decade, three-dimensional landmarking has gained attention for different applications, such as face recognition for both identification of suspects and authentication, facial expression recognition, corrective and aesthetic surgery, syndrome study and diagnosis. This work focuses on the last one by proposing a geometrically-based landmark extraction algorithm aimed at diagnosing syndromes on babies before their birth. Pivotal role in this activity is the support provided by physicians and 3D ultrasound tools for working on real faces. In particular, the landmarking algorithm here proposed only relies on descriptors coming from Differential Geometry (Gaussian, mean, and principal curvatures, derivatives, coefficients of first and second fundamental forms, Shape and Curvedness indexes and is tested on nine facial point clouds referred to nine babies taken by a three-dimensional ultrasound tool at different weeks' gestation. The results obtained, validated with the support of four practitioners, show that the localization is quite accurate. All errors lie in the range between 0 and 3.5 mm and the mean distance for each shell is in the range between 0.6 and 1.6 mm. The landmarks showing the highest errors are the ones belonging to the mouth region. Instead, the most precise landmark is the pronasal, on the nose tip, with a mean distance of 0.55 mm. Relying on current literature, this study is something missing in the state-of-the-art of the field, as present facial studies on 3D ultrasound do not work on automatic landmarking yet.

  6. A new combined prior based reconstruction method for compressed sensing in 3D ultrasound imaging

    Uddin, Muhammad S.; Islam, Rafiqul; Tahtali, Murat; Lambert, Andrew J.; Pickering, Mark R.

    2015-03-01

    Ultrasound (US) imaging is one of the most popular medical imaging modalities, with 3D US imaging gaining popularity recently due to its considerable advantages over 2D US imaging. However, as it is limited by long acquisition times and the huge amount of data processing it requires, methods for reducing these factors have attracted considerable research interest. Compressed sensing (CS) is one of the best candidates for accelerating the acquisition rate and reducing the data processing time without degrading image quality. However, CS is prone to introduce noise-like artefacts due to random under-sampling. To address this issue, we propose a combined prior-based reconstruction method for 3D US imaging. A Laplacian mixture model (LMM) constraint in the wavelet domain is combined with a total variation (TV) constraint to create a new regularization regularization prior. An experimental evaluation conducted to validate our method using synthetic 3D US images shows that it performs better than other approaches in terms of both qualitative and quantitative measures.

  7. Segmentation of the common carotid artery with active shape models from 3D ultrasound images

    Yang, Xin; Jin, Jiaoying; He, Wanji; Yuchi, Ming; Ding, Mingyue

    2012-03-01

    Carotid atherosclerosis is a major cause of stroke, a leading cause of death and disability. In this paper, we develop and evaluate a new segmentation method for outlining both lumen and adventitia (inner and outer walls) of common carotid artery (CCA) from three-dimensional ultrasound (3D US) images for carotid atherosclerosis diagnosis and evaluation. The data set consists of sixty-eight, 17× 2× 2, 3D US volume data acquired from the left and right carotid arteries of seventeen patients (eight treated with 80mg atorvastain and nine with placebo), who had carotid stenosis of 60% or more, at baseline and after three months of treatment. We investigate the use of Active Shape Models (ASMs) to segment CCA inner and outer walls after statin therapy. The proposed method was evaluated with respect to expert manually outlined boundaries as a surrogate for ground truth. For the lumen and adventitia segmentations, respectively, the algorithm yielded Dice Similarity Coefficient (DSC) of 93.6%+/- 2.6%, 91.8%+/- 3.5%, mean absolute distances (MAD) of 0.28+/- 0.17mm and 0.34 +/- 0.19mm, maximum absolute distances (MAXD) of 0.87 +/- 0.37mm and 0.74 +/- 0.49mm. The proposed algorithm took 4.4 +/- 0.6min to segment a single 3D US images, compared to 11.7+/-1.2min for manual segmentation. Therefore, the method would promote the translation of carotid 3D US to clinical care for the fast, safety and economical monitoring of the atherosclerotic disease progression and regression during therapy.

  8. Automated 3D ultrasound elastography of the breast: a phantom validation study

    Hendriks, Gijs A. G. M.; Holländer, Branislav; Menssen, Jan; Milkowski, Andy; Hansen, Hendrik H. G.; de Korte, Chris L.

    2016-04-01

    In breast cancer screening, the automated breast volume scanner (ABVS) was introduced as an alternative for mammography since the latter technique is less suitable for women with dense breasts. Although clinical studies show promising results, clinicians report two disadvantages: long acquisition times (>90 s) introducing breathing artefacts, and high recall rates due to detection of many small lesions of uncertain malignant potential. Technical improvements for faster image acquisition and better discrimination between benign and malignant lesions are thus required. Therefore, the aim of this study was to investigate if 3D ultrasound elastography using plane-wave imaging is feasible. Strain images of a breast elastography phantom were acquired by an ABVS-mimicking device that allowed axial and elevational movement of the attached transducer. Pre- and post-deformation volumes were acquired with different constant speeds (between 1.25 and 40.0 mm s-1) and by three protocols: Go-Go (pre- and post-volumes with identical start and end positions), Go-Return (similar to Go-Go with opposite scanning directions) and Control (pre- and post-volumes acquired per position, this protocol can be seen as reference). Afterwards, 2D and 3D cross-correlation and strain algorithms were applied to the acquired volumes and the results were compared. The Go-Go protocol was shown to be superior with better strain image quality (CNRe and SNRe) than Go-Return and to be similar as Control. This can be attributed to applying opposite mechanical forces to the phantom during the Go-Return protocol, leading to out-of-plane motion. This motion was partly compensated by using 3D cross-correlation. However, the quality was still inferior to Go-Go. Since these results were obtained in a phantom study with controlled deformations, the effect of possible uncontrolled in vivo tissue motion artefacts has to be addressed in future studies. In conclusion, it seems feasible to implement 3D ultrasound

  9. Simulation Study of Real Time 3-D Synthetic Aperture Sequential Beamforming for Ultrasound Imaging

    Hemmsen, Martin Christian; Rasmussen, Morten Fischer; Stuart, Matthias Bo;

    2014-01-01

    This paper presents a new beamforming method for real-time three-dimensional (3-D) ultrasound imaging using a 2-D matrix transducer. To obtain images with sufficient resolution and contrast, several thousand elements are needed. The proposed method reduces the required channel count from the...... transducer to the main imaging system, by including electronics in the transducer handle. The reduction of element channel count is achieved using a sequential beamforming scheme. The beamforming scheme is a combination of a fixed focus beamformer in the transducer and a second dynamic focus beamformer in...... the main system. The real-time imaging capability is achieved using a synthetic aperture beamforming technique, utilizing the transmit events to generate a set of virtual elements that in combination can generate an image. The two core capabilities in combination is named Synthetic Aperture Sequential...

  10. GPCA vs. PCA in Recognition and 3-D Localization of Ultrasound Reflectors

    Carlos A. Luna

    2010-05-01

    Full Text Available In this paper, a new method of classification and localization of reflectors, using the time-of-flight (TOF data obtained from ultrasonic transducers, is presented. The method of classification and localization is based on Generalized Principal Component Analysis (GPCA applied to the TOF values obtained from a sensor that contains four ultrasound emitters and 16 receivers. Since PCA works with vectorized representations of TOF, it does not take into account the spatial locality of receivers. The GPCA works with two-dimensional representations of TOF, taking into account information on the spatial position of the receivers. This report includes a detailed description of the method of classification and localization and the results of achieved tests with three types of reflectors in 3-D environments: planes, edges, and corners. The results in terms of processing time, classification and localization were very satisfactory for the reflectors located in the range of 50–350 cm.

  11. 3D ultrasound-CT registration of the liver using combined landmark-intensity information

    An important issue in computer-assisted surgery of the liver is a fast and reliable transfer of preoperative resection plans to the intraoperative situation. One problem is to match the planning data, derived from preoperative CT or MR images, with 3D ultrasound images of the liver, acquired during surgery. As the liver deforms significantly in the intraoperative situation non-rigid registration is necessary. This is a particularly challenging task because pre- and intraoperative image data stem from different modalities and ultrasound images are generally very noisy. One way to overcome these problems is to incorporate prior knowledge into the registration process. We propose a method of combining anatomical landmark information with a fast non-parametric intensity registration approach. Mathematically, this leads to a constrained optimization problem. As distance measure we use the normalized gradient field which allows for multimodal image registration. A qualitative and quantitative validation on clinical liver data sets of three different patients has been performed. We used the distance of dense corresponding points on vessel center lines for quantitative validation. The combined landmark and intensity approach improves the mean and percentage of point distances above 3 mm compared to rigid and thin-plate spline registration based only on landmarks. The proposed algorithm offers the possibility to incorporate additional a priori knowledge - in terms of few landmarks - provided by a human expert into a non-rigid registration process. (orig.)

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

    Suomi, Visa; Treeby, Bradley; Cleveland, Robin

    2016-01-01

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

  13. Ultrasound and 3D Skin Imaging: Methods to Evaluate Efficacy of Striae Distensae Treatment

    Mariella Bleve

    2012-01-01

    Full Text Available Background. Over time, the striae rubra develop into striae alba that appear white, flat, and depressed. It is very important to determine the optimum striae management. In order to evaluate the effectiveness of these therapies, objective measurement tools are necessary. Objective. The aim of this study is to evaluate if ultrasonography and PRIMOS can be used to obtain an objective assessment of stretch marks type and stage; furthermore, we aim to apply these techniques to evaluate the efficacy of a topical treatment. Methods. 20 volunteers were enrolled with a two-month study. A marketed cosmetic product was used as the active over one body area. The controlateral area with stretch marks was treated with a “placebo” formulation without active, as a control. The instrumental evaluation was carried out at the beginning of the trial (baseline values or 0, after 1 month (1, and at the end of the study (2. Results. PRIMOS was able to measure and document striae distensae maturation; furthermore, ultrasound imaging permitted to visualize and diagnose the striae. Statistical analysis of skin roughness demonstrated a statistically significant reduction of Rp value only in a treated group. In fact, the Rp value represented a maximum peak height in the area selected. These results demonstrated that after two months of treatment only the striae rubra can be treated successfully. Conclusions. This work demonstrated that the 22MHz ultrasound can diagnose stretch marks; PRIMOS device can detect and measure striae distensae type and maturation. Furthermore, the high-frequency ultrasound and the 3D image device, described in this work, can be successfully employed in order to evaluate the efficacy of a topical treatment.

  14. A preliminary evaluation work on a 3D ultrasound imaging system for 2D array transducer

    Zhong, Xiaoli; Li, Xu; Yang, Jiali; Li, Chunyu; Song, Junjie; Ding, Mingyue; Yuchi, Ming

    2016-04-01

    This paper presents a preliminary evaluation work on a pre-designed 3-D ultrasound imaging system. The system mainly consists of four parts, a 7.5MHz, 24×24 2-D array transducer, the transmit/receive circuit, power supply, data acquisition and real-time imaging module. The row-column addressing scheme is adopted for the transducer fabrication, which greatly reduces the number of active channels . The element area of the transducer is 4.6mm by 4.6mm. Four kinds of tests were carried out to evaluate the imaging performance, including the penetration depth range, axial and lateral resolution, positioning accuracy and 3-D imaging frame rate. Several strong reflection metal objects , fixed in a water tank, were selected for the purpose of imaging due to a low signal-to-noise ratio of the transducer. The distance between the transducer and the tested objects , the thickness of aluminum, and the seam width of the aluminum sheet were measured by a calibrated micrometer to evaluate the penetration depth, the axial and lateral resolution, respectively. The experiment al results showed that the imaging penetration depth range was from 1.0cm to 6.2cm, the axial and lateral resolution were 0.32mm and 1.37mm respectively, the imaging speed was up to 27 frames per second and the positioning accuracy was 9.2%.

  15. Automatic 3D ultrasound calibration for image guided therapy using intramodality image registration

    Many real time ultrasound (US) guided therapies can benefit from management of motion-induced anatomical changes with respect to a previously acquired computerized anatomy model. Spatial calibration is a prerequisite to transforming US image information to the reference frame of the anatomy model. We present a new method for calibrating 3D US volumes using intramodality image registration, derived from the ‘hand-eye’ calibration technique. The method is fully automated by implementing data rejection based on sensor displacements, automatic registration over overlapping image regions, and a self-consistency error metric evaluated continuously during calibration. We also present a novel method for validating US calibrations based on measurement of physical phantom displacements within US images. Both calibration and validation can be performed on arbitrary phantoms. Results indicate that normalized mutual information and localized cross correlation produce the most accurate 3D US registrations for calibration. Volumetric image alignment is more accurate and reproducible than point selection for validating the calibrations, yielding <1.5 mm root mean square error, a significant improvement relative to previously reported hand-eye US calibration results. Comparison of two different phantoms for calibration and for validation revealed significant differences for validation (p = 0.003) but not for calibration (p = 0.795). (paper)

  16. Understanding of percutaneous puncture under guidance of ultrasound in treating peritoneal and perinephritic abscess

    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)

  17. Mapping 3D Strains with Ultrasound Speckle Tracking: Method Validation and Initial Results in Porcine Scleral Inflation.

    Cruz Perez, Benjamin; Pavlatos, Elias; Morris, Hugh J; Chen, Hong; Pan, Xueliang; Hart, Richard T; Liu, Jun

    2016-07-01

    This study aimed to develop and validate a high frequency ultrasound method for measuring distributive, 3D strains in the sclera during elevations of intraocular pressure. A 3D cross-correlation based speckle-tracking algorithm was implemented to compute the 3D displacement vector and strain tensor at each tracking point. Simulated ultrasound radiofrequency data from a sclera-like structure at undeformed and deformed states with known strains were used to evaluate the accuracy and signal-to-noise ratio (SNR) of strain estimation. An experimental high frequency ultrasound (55 MHz) system was built to acquire 3D scans of porcine eyes inflated from 15 to 17 and then 19 mmHg. Simulations confirmed good strain estimation accuracy and SNR (e.g., the axial strains had less than 4.5% error with SNRs greater than 16.5 for strains from 0.005 to 0.05). Experimental data in porcine eyes showed increasing tensile, compressive, and shear strains in the posterior sclera during inflation, with a volume ratio close to one suggesting near-incompressibility. This study established the feasibility of using high frequency ultrasound speckle tracking for measuring 3D tissue strains and its potential to characterize physiological deformations in the posterior eye. PMID:26563101

  18. Semiautomatic registration of 3D transabdominal ultrasound images for patient repositioning during postprostatectomy radiotherapy

    Purpose: The aim of the present work is to propose and evaluate registration algorithms of three-dimensional (3D) transabdominal (TA) ultrasound (US) images to setup postprostatectomy patients during radiation therapy. Methods: Three registration methods have been developed and evaluated to register a reference 3D-TA-US image acquired during the planning CT session and a 3D-TA-US image acquired before each treatment session. The first method (method A) uses only gray value information, whereas the second one (method B) uses only gradient information. The third one (method C) combines both sets of information. All methods restrict the comparison to a region of interest computed from the dilated reference positioning volume drawn on the reference image and use mutual information as a similarity measure. The considered geometric transformations are translations and have been optimized by using the adaptive stochastic gradient descent algorithm. Validation has been carried out using manual registration by three operators of the same set of image pairs as the algorithms. Sixty-two treatment US images of seven patients irradiated after a prostatectomy have been registered to their corresponding reference US image. The reference registration has been defined as the average of the manual registration values. Registration error has been calculated by subtracting the reference registration from the algorithm result. For each session, the method has been considered a failure if the registration error was above both the interoperator variability of the session and a global threshold of 3.0 mm. Results: All proposed registration algorithms have no systematic bias. Method B leads to the best results with mean errors of −0.6, 0.7, and −0.2 mm in left–right (LR), superior–inferior (SI), and anterior–posterior (AP) directions, respectively. With this method, the standard deviations of the mean error are of 1.7, 2.4, and 2.6 mm in LR, SI, and AP directions, respectively

  19. Semiautomatic registration of 3D transabdominal ultrasound images for patient repositioning during postprostatectomy radiotherapy

    Presles, Benoît, E-mail: benoit.presles@creatis.insa-lyon.fr; Rit, Simon; Sarrut, David [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Lyon F-69621, France and Léon Bérard Cancer Center, Université de Lyon, Lyon F-69373 (France); Fargier-Voiron, Marie; Liebgott, Hervé [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Lyon F-69621 (France); Biston, Marie-Claude; Munoz, Alexandre; Pommier, Pascal [Léon Bérard Cancer Center, Université de Lyon, Lyon F-69373 (France); Lynch, Rod [The Andrew Love Cancer Centre, University Hospital Geelong, Geelong 3220 (Australia)

    2014-12-15

    Purpose: The aim of the present work is to propose and evaluate registration algorithms of three-dimensional (3D) transabdominal (TA) ultrasound (US) images to setup postprostatectomy patients during radiation therapy. Methods: Three registration methods have been developed and evaluated to register a reference 3D-TA-US image acquired during the planning CT session and a 3D-TA-US image acquired before each treatment session. The first method (method A) uses only gray value information, whereas the second one (method B) uses only gradient information. The third one (method C) combines both sets of information. All methods restrict the comparison to a region of interest computed from the dilated reference positioning volume drawn on the reference image and use mutual information as a similarity measure. The considered geometric transformations are translations and have been optimized by using the adaptive stochastic gradient descent algorithm. Validation has been carried out using manual registration by three operators of the same set of image pairs as the algorithms. Sixty-two treatment US images of seven patients irradiated after a prostatectomy have been registered to their corresponding reference US image. The reference registration has been defined as the average of the manual registration values. Registration error has been calculated by subtracting the reference registration from the algorithm result. For each session, the method has been considered a failure if the registration error was above both the interoperator variability of the session and a global threshold of 3.0 mm. Results: All proposed registration algorithms have no systematic bias. Method B leads to the best results with mean errors of −0.6, 0.7, and −0.2 mm in left–right (LR), superior–inferior (SI), and anterior–posterior (AP) directions, respectively. With this method, the standard deviations of the mean error are of 1.7, 2.4, and 2.6 mm in LR, SI, and AP directions, respectively

  20. 3-D Ultrasound Imaging Performance of a Row-Column Addressed 2-D Array Transducer: A Measurement Study

    Rasmussen, Morten Fischer; Jensen, Jørgen Arendt

    A real-time 3-D ultrasound measurement using only 32 elements and 32 emissions is presented. The imaging quality is compared to a conventionally fully addressed array using 1024 elements and 256 emissions. The main-lobe of the measured line spread function is almost identical, but the side...

  1. Improved Human Bone Marrow Mesenchymal Stem Cell Osteogenesis in 3D Bioprinted Tissue Scaffolds with Low Intensity Pulsed Ultrasound Stimulation.

    Zhou, Xuan; Castro, Nathan J; Zhu, Wei; Cui, Haitao; Aliabouzar, Mitra; Sarkar, Kausik; Zhang, Lijie Grace

    2016-01-01

    3D printing and ultrasound techniques are showing great promise in the evolution of human musculoskeletal tissue repair and regeneration medicine. The uniqueness of the present study was to combine low intensity pulsed ultrasound (LIPUS) and advanced 3D printing techniques to synergistically improve growth and osteogenic differentiation of human mesenchymal stem cells (MSC). Specifically, polyethylene glycol diacrylate bioinks containing cell adhesive Arginine-Glycine-Aspartic acid-Serene (RGDS) peptide and/or nanocrystalline hydroxyapatite (nHA) were used to fabricate 3D scaffolds with different geometric patterns via novel table-top stereolithography 3D printer. The resultant scaffolds provide a highly porous and interconnected 3D environment to support cell proliferation. Scaffolds with small square pores were determined to be the optimal geometric pattern for MSC attachment and growth. The optimal LIPUS working parameters were determined to be 1.5 MHz, 20% duty cycle with 150 mW/cm(2) intensity. Results demonstrated that RGDS peptide and nHA containing 3D printed scaffolds under LIPUS treatment can greatly promote MSC proliferation, alkaline phosphatase activity, calcium deposition and total protein content. These results illustrate the effectiveness of the combination of LIPUS and biomimetic 3D printing scaffolds as a valuable combinatorial tool for improved MSC function, thus make them promising for future clinical and various regenerative medicine application. PMID:27597635

  2. Known-component 3D-2D registration for image guidance and quality assurance in spine surgery pedicle screw placement

    Uneri, A.; Stayman, J. W.; De Silva, T.; Wang, A. S.; Kleinszig, G.; Vogt, S.; Khanna, A. J.; Wolinsky, J.-P.; Gokaslan, Z. L.; Siewerdsen, J. H.

    2015-03-01

    Purpose. To extend the functionality of radiographic / fluoroscopic imaging systems already within standard spine surgery workflow to: 1) provide guidance of surgical device analogous to an external tracking system; and 2) provide intraoperative quality assurance (QA) of the surgical product. Methods. Using fast, robust 3D-2D registration in combination with 3D models of known components (surgical devices), the 3D pose determination was solved to relate known components to 2D projection images and 3D preoperative CT in near-real-time. Exact and parametric models of the components were used as input to the algorithm to evaluate the effects of model fidelity. The proposed algorithm employs the covariance matrix adaptation evolution strategy (CMA-ES) to maximize gradient correlation (GC) between measured projections and simulated forward projections of components. Geometric accuracy was evaluated in a spine phantom in terms of target registration error at the tool tip (TREx), and angular deviation (TREΦ) from planned trajectory. Results. Transpedicle surgical devices (probe tool and spine screws) were successfully guided with TREx30° (easily accommodated on a mobile C-arm). QA of the surgical product based on 3D-2D registration demonstrated the detection of pedicle screw breach with TRExConclusions. 3D-2D registration combined with 3D models of known surgical components provides a novel method for near-real-time guidance and quality assurance using a mobile C-arm without external trackers or fiducial markers. Ongoing work includes determination of optimal views based on component shape and trajectory, improved robustness to anatomical deformation, and expanded preclinical testing in spine and intracranial surgeries.

  3. Computer-aided detection of cancer in automated 3-D breast ultrasound.

    Tan, Tao; Platel, Bram; Mus, Roel; Tabar, László; Mann, Ritse M; Karssemeijer, Nico

    2013-09-01

    Automated 3-D breast ultrasound (ABUS) has gained a lot of interest and may become widely used in screening of dense breasts, where sensitivity of mammography is poor. However, reading ABUS images is time consuming, and subtle abnormalities may be missed. Therefore, we are developing a computer aided detection (CAD) system to help reduce reading time and prevent errors. In the multi-stage system we propose, segmentations of the breast, the nipple and the chestwall are performed, providing landmarks for the detection algorithm. Subsequently, voxel features characterizing coronal spiculation patterns, blobness, contrast, and depth are extracted. Using an ensemble of neural-network classifiers, a likelihood map indicating potential abnormality is computed. Local maxima in the likelihood map are determined and form a set of candidates in each image. These candidates are further processed in a second detection stage, which includes region segmentation, feature extraction and a final classification. On region level, classification experiments were performed using different classifiers including an ensemble of neural networks, a support vector machine, a k-nearest neighbors, a linear discriminant, and a gentle boost classifier. Performance was determined using a dataset of 238 patients with 348 images (views), including 169 malignant and 154 benign lesions. Using free response receiver operating characteristic (FROC) analysis, the system obtains a view-based sensitivity of 64% at 1 false positives per image using an ensemble of neural-network classifiers. PMID:23693128

  4. Portable high-intensity focused ultrasound system with 3D electronic steering, real-time cavitation monitoring, and 3D image reconstruction algorithms: a preclinical study in pigs

    Choi, Jin Woo; Lee, Jae Young; Hwang, Eui Jin; Hwang, In Pyeong; Woo, Sung Min; Lee, Chang Joo; Park, Eun Joo; Choi, Byung Ihn [Dept. of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-10-15

    The aim of this study was to evaluate the safety and accuracy of a new portable ultrasonography-guided high-intensity focused ultrasound (USg-HIFU) system with a 3-dimensional (3D) electronic steering transducer, a simultaneous ablation and imaging module, real-time cavitation monitoring, and 3D image reconstruction algorithms. To address the accuracy of the transducer, hydrophones in a water chamber were used to assess the generation of sonic fields. An animal study was also performed in five pigs by ablating in vivo thighs by single-point sonication (n=10) or volume sonication (n=10) and ex vivo kidneys by single-point sonication (n=10). Histological and statistical analyses were performed. In the hydrophone study, peak voltages were detected within 1.0 mm from the targets on the y- and z-axes and within 2.0-mm intervals along the x-axis (z-axis, direction of ultrasound propagation; y- and x-axes, perpendicular to the direction of ultrasound propagation). Twenty-nine of 30 HIFU sessions successfully created ablations at the target. The in vivo porcine thigh study showed only a small discrepancy (width, 0.5-1.1 mm; length, 3.0 mm) between the planning ultrasonograms and the pathological specimens. Inordinate thermal damage was not observed in the adjacent tissues or sonic pathways in the in vivo thigh and ex vivo kidney studies. Our study suggests that this new USg-HIFU system may be a safe and accurate technique for ablating soft tissues and encapsulated organs.

  5. Robust 3-D Algorithm for Flare Planning and Guidance for Impaired Aircraft Project

    National Aeronautics and Space Administration — Development of a robust nonlinear guidance law for planning and executing the flare-touchdown maneuver for impaired aircraft under adverse wind conditions is...

  6. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    Hornblower, V. D. M.; Yu, E.; Fenster, A.; Battista, J. J.; Malthaner, R. A.

    2007-01-01

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo.

  7. The effect of object speed and direction on the performance of 3D speckle tracking using a 3D swept-volume ultrasound probe

    Three-dimensional (3D) soft tissue tracking using 3D ultrasound is of interest for monitoring organ motion during therapy. Previously we demonstrated feature tracking of respiration-induced liver motion in vivo using a 3D swept-volume ultrasound probe. The aim of this study was to investigate how object speed affects the accuracy of tracking ultrasonic speckle in the absence of any structural information, which mimics the situation in homogenous tissue for motion in the azimuthal and elevational directions. For object motion prograde and retrograde to the sweep direction of the transducer, the spatial sampling frequency increases or decreases with object speed, respectively. We examined the effect object motion direction of the transducer on tracking accuracy. We imaged a homogenous ultrasound speckle phantom whilst moving the probe with linear motion at a speed of 0–35 mm s−1. Tracking accuracy and precision were investigated as a function of speed, depth and direction of motion for fixed displacements of 2 and 4 mm. For the azimuthal direction, accuracy was better than 0.1 and 0.15 mm for displacements of 2 and 4 mm, respectively. For a 2 mm displacement in the elevational direction, accuracy was better than 0.5 mm for most speeds. For 4 mm elevational displacement with retrograde motion, accuracy and precision reduced with speed and tracking failure was observed at speeds of greater than 14 mm s−1. Tracking failure was attributed to speckle de-correlation as a result of decreasing spatial sampling frequency with increasing speed of retrograde motion. For prograde motion, tracking failure was not observed. For inter-volume displacements greater than 2 mm, only prograde motion should be tracked which will decrease temporal resolution by a factor of 2. Tracking errors of the order of 0.5 mm for prograde motion in the elevational direction indicates that using the swept probe technology speckle tracking accuracy is currently too poor to track homogenous tissue

  8. 3D perfused brain phantom for interstitial ultrasound thermal therapy and imaging: design, construction and characterization

    Thermal therapy has emerged as an independent modality of treating some tumors. In many clinics the hyperthermia, one of the thermal therapy modalities, has been used adjuvant to radio- or chemotherapy to substantially improve the clinical treatment outcomes. In this work, a methodology for building a realistic brain phantom for interstitial ultrasound low dose-rate thermal therapy of the brain is proposed. A 3D brain phantom made of the tissue mimicking material (TMM) had the acoustic and thermal properties in the 20–32 °C range, which is similar to that of a brain at 37 °C. The phantom had 10–11% by mass of bovine gelatin powder dissolved in ethylene glycol. The TMM sonicated at 1 MHz, 1.6 MHz and 2.5 MHz yielded the amplitude attenuation coefficients of 62  ±  1 dB m−1, 115  ±  4 dB m−1 and 175  ±  9 dB m−1, respectively. The density and acoustic speed determination at room temperature (∼24 °C) gave 1040  ±  40 kg m−3 and 1545  ±  44 m s−1, respectively. The average thermal conductivity was 0.532 W m−1 K−1. The T1 and T2 values of the TMM were 207  ±  4 and 36.2  ±  0.4 ms, respectively. We envisage the use of our phantom for treatment planning and for quality assurance in MRI based temperature determination. Our phantom preparation methodology may be readily extended to other thermal therapy technologies. (paper)

  9. 3D Power Doppler ultrasound and computerised placental assessment in normal pregnancy

    Background: In recent years there have been significant developments in the use of 3D Power Doppler (3DPD) imaging and quantitative 3DPD histogram analysis to estimate both placental volume and intra-placental vasculature. This study aims to determine if placental volume, vascularisation and blood flow are correlated with gestational age in normal pregnancy. It also examines whether or not a new software method for analysis of percentage calcification (the ‘placentometer’) correlates well with gestation. Material and method: This was a prospective cohort study of 250 women with normal pregnancies (12 + 6 to 39 + 5 weeks gestation). 3DPD ultrasound was used to evaluate placental volume, vascularisation index (VI), flow index (FI) and vascularisation-flow index (VFI). Placental volume (calculated at 35–40 weeks gestation), was correlated with birth weight. Following each scan the percentage of calcification was also calculated using the placentometer. Results: Placental volume correlated significantly with gestational age: 66.676 + 0.623 × GA (P < 0.001). No significant change with gestation was noted in VI, FI and VFI (VI: P = 0.199, FI: P = 0.299, VFI: P = 0.557). Software analysis of the percentage of calcification, demonstrated the expected increase in calcification as gestation increased: −4.605 + 0.032 × GA (P < 0.001). From 35 to 40 weeks gestation volume was related to birth weight (P < 0.01). Conclusion: This study shows that in normal low-risk pregnancy placental volume increases with gestational age, whereas vascularisation and blood flow are independent of gestation. Placental volume in late pregnancy is related to birth weight. Software analysis of the percentage of calcification demonstrates an increase with advancing gestation

  10. Efficacy and safety in performing of large bore percutaneous nephrostomy under ultrasound guidance

    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

  11. Consequences of Intermodality Registration Errors for Intramodality 3D Ultrasound IGRT.

    van der Meer, Skadi; Seravalli, Enrica; Fontanarosa, Davide; Bloemen-van Gurp, Esther J; Verhaegen, Frank

    2016-08-01

    Intramodality ultrasound image-guided radiotherapy systems compare daily ultrasound to reference ultrasound images. Nevertheless, because the actual treatment planning is based on a reference computed tomography image, and not on a reference ultrasound image, their accuracy depends partially on the correct intermodality registration of the reference ultrasound and computed tomography images for treatment planning. The error propagation in daily patient positioning due to potential registration errors at the planning stage was assessed in this work. Five different scenarios were simulated involving shifts or rotations of ultrasound or computed tomography images. The consequences of several workflow procedures were tested with a phantom setup. As long as the reference ultrasound and computed tomography images are made to match, the patient will be in the correct treatment position. In an example with a phantom measurement, the accuracy of the performed manual fusion was found to be ≤2 mm. In clinical practice, manual registration of patient images is expected to be more difficult. Uncorrected mismatches will lead to a systematically incorrect final patient position because there will be no indication that there was a misregistration between the computed tomography and reference ultrasound images. In the treatment room, the fusion with the computed tomography image will not be visible and based on the ultrasound images the patient position seems correct. PMID:26048909

  12. Multi-modality fusion of CT, 3D ultrasound, and tracked strain images for breast irradiation planning

    Foroughi, Pezhman; Csoma, Csaba; Rivaz, Hassan; Fichtinger, Gabor; Zellars, Richard; Hager, Gregory; Boctor, Emad

    2009-02-01

    Breast irradiation significantly reduces the risk of recurrence of cancer. There is growing evidence suggesting that irradiation of only the involved area of the breast, partial breast irradiation (PBI), is as effective as whole breast irradiation. Benefits of PBI include shortened treatment time, and perhaps fewer side effects as less tissue is treated. However, these benefits cannot be realized without precise and accurate localization of the lumpectomy cavity. Several studies have shown that accurate delineation of the cavity in CT scans is very challenging and the delineated volumes differ dramatically over time and among users. In this paper, we propose utilizing 3D ultrasound (3D-US) and tracked strain images as complementary modalities to reduce uncertainties associated with current CT planning workflow. We present the early version of an integrated system that fuses 3D-US and real-time strain images. For the first time, we employ tracking information to reduce the noise in calculation of strain image by choosing the properly compressed frames and to position the strain image within the ultrasound volume. Using this system, we provide the tools to retrieve additional information from 3D-US and strain image alongside the CT scan. We have preliminarily evaluated our proposed system in a step-by-step fashion using a breast phantom and clinical experiments.

  13. Automated segmentation method for the 3D ultrasound carotid image based on geometrically deformable model with automatic merge function

    Li, Xiang; Wang, Zigang; Lu, Hongbing; Liang, Zhengrong

    2002-05-01

    Stenosis of the carotid is the most common cause of the stroke. The accurate measurement of the volume of the carotid and visualization of its shape are helpful in improving diagnosis and minimizing the variability of assessment of the carotid disease. Due to the complex anatomic structure of the carotid, it is mandatory to define the initial contours in every slice, which is very difficult and usually requires tedious manual operations. The purpose of this paper is to propose an automatic segmentation method, which automatically provides the contour of the carotid from the 3-D ultrasound image and requires minimum user interaction. In this paper, we developed the Geometrically Deformable Model (GDM) with automatic merge function. In our algorithm, only two initial contours in the topmost slice and four parameters are needed in advance. Simulated 3-D ultrasound image was used to test our algorithm. 3-D display of the carotid obtained by our algorithm showed almost identical shape with true 3-D carotid image. In addition, experimental results also demonstrated that error of the volume measurement of the carotid based on the three different initial contours is less that 1% and its speed was a very fast.

  14. A 3D Freehand Ultrasound System for Multi-view Reconstructions from Sparse 2D Scanning Planes

    Agurto Carla

    2011-01-01

    Full Text Available Abstract Background A significant limitation of existing 3D ultrasound systems comes from the fact that the majority of them work with fixed acquisition geometries. As a result, the users have very limited control over the geometry of the 2D scanning planes. Methods We present a low-cost and flexible ultrasound imaging system that integrates several image processing components to allow for 3D reconstructions from limited numbers of 2D image planes and multiple acoustic views. Our approach is based on a 3D freehand ultrasound system that allows users to control the 2D acquisition imaging using conventional 2D probes. For reliable performance, we develop new methods for image segmentation and robust multi-view registration. We first present a new hybrid geometric level-set approach that provides reliable segmentation performance with relatively simple initializations and minimum edge leakage. Optimization of the segmentation model parameters and its effect on performance is carefully discussed. Second, using the segmented images, a new coarse to fine automatic multi-view registration method is introduced. The approach uses a 3D Hotelling transform to initialize an optimization search. Then, the fine scale feature-based registration is performed using a robust, non-linear least squares algorithm. The robustness of the multi-view registration system allows for accurate 3D reconstructions from sparse 2D image planes. Results Volume measurements from multi-view 3D reconstructions are found to be consistently and significantly more accurate than measurements from single view reconstructions. The volume error of multi-view reconstruction is measured to be less than 5% of the true volume. We show that volume reconstruction accuracy is a function of the total number of 2D image planes and the number of views for calibrated phantom. In clinical in-vivo cardiac experiments, we show that volume estimates of the left ventricle from multi-view reconstructions

  15. Measurement of the 3D arterial wall strain tensor using intravascular B-mode ultrasound images: a feasibility study

    Liang, Yun; Zhu, Hui; Friedman, Morton H.

    2010-11-01

    Intravascular ultrasound (IVUS) elastography is a promising tool for studying atherosclerotic plaque composition and assessing plaque vulnerability. Current IVUS elastography techniques can measure the 1D or 2D strain of the vessel wall using various motion tracking algorithms. Since biological soft tissue tends to deform non-uniformly in 3D, measurement of the complete 3D strain tensor is desirable for more rigorous analysis of arterial wall mechanics. In this paper, we extend our previously developed method of 2D arterial wall strain measurement based on non-rigid image registration into 3D strain measurement. The new technique registers two image volumes acquired from the same vessel segment under different levels of luminal pressure and longitudinal stress. The 3D displacement field obtained from the image registration is used to calculate the local 3D strain tensor. From the 3D strain tensor, radial, circumferential and longitudinal strain distributions can be obtained and displayed. This strain tensor measurement method is validated and evaluated using IVUS images of healthy porcine carotid arteries subjected to a luminal pressure increase and longitudinal stretch. The ability of the algorithm to overcome systematic noise was tested, as well as the consistency of the results under different longitudinal frame resolutions.

  16. 2D and 3D endoanal and translabial ultrasound measurement variation in normal postpartum measurements of the anal sphincter complex

    MERIWETHER, Kate V.; HALL, Rebecca J.; LEEMAN, Lawrence M.; MIGLIACCIO, Laura; QUALLS, Clifford; ROGERS, Rebecca G.

    2015-01-01

    Introduction Women may experience anal sphincter anatomy changes after vaginal or Cesarean delivery. Therefore, accurate and acceptable imaging options to evaluate the anal sphincter complex (ASC) are needed. ASC measurements may differ between translabial (TL-US) and endoanal ultrasound (EA-US) imaging and between 2D and 3D ultrasound. The objective of this analysis was to describe measurement variation between these modalities. Methods Primiparous women underwent 2D and 3D TL-US imaging of the ASC six months after a vaginal birth (VB) or Cesarean delivery (CD). A subset of women also underwent EA-US measurements. Measurements included the internal anal sphincter (IAS) thickness at proximal, mid, and distal levels and the external anal sphincter (EAS) at 3, 6, 9, and 12 o’clock positions as well as bilateral thickness of the pubovisceralis muscle (PVM). Results 433 women presented for US: 423 had TL-US and 64 had both TL-US and EA-US of the ASC. All IAS measurements were significantly thicker on TL-US than EA-US (all p0.20). On both TL-US and EA-US, there were multiple sites where significant asymmetry existed in left versus right measurements. Conclusion The ultrasound modality used to image the ASC introduces small but significant changes in measurements, and the direction of the bias depends on the muscle and location being imaged. PMID:25344221

  17. Utilizing 3-D and 4-D ultrasound systems to improve radiation treatment of cervix and prostate cancer patients

    Baker, Mariwan

    megavoltage (MV) image guided radiotherapy (IGRT) methods are developed. However, these ionization systems provide poor visualization of soft tissue, and therefore the bone matching is frequently applied as a daily tumor alignment method in cervical radiotherapy. In this project, the Clarity 3D ultrasound...... conventional probe (C-probe) has limitations, while applying transabdominal US (TAUS) scan, when it came to capturing the entire uterus owing to the difficulty in probe handling. Contrarily, the novel autoscan-probe (A-probe) was shown to be capable of capturing the entire uterus in almost all of the scans...... images, which has limitations in addressing real-time prostate motion, and includes inter-observer variations while matching image to image. In this project, the recently developed transperineal ultrasound 4D autoscan probe is used to investigate the real-time prostate monitoring. The purpose of this...

  18. Ultrasound-based technique for intrathoracic surgical guidance

    Huang, Xishi; Hill, Nicholas A.; Peters, Terry M.

    2005-04-01

    Image-guided procedures within the thoracic cavity require accurate registration of a pre-operative virtual model to the patient. Currently, surface landmarks are used for thoracic cavity registration; however, this approach is unreliable due to skin movement relative to the ribs. An alternative method for providing surgeons with image feedback in the operating room is to integrate images acquired during surgery with images acquired pre-operatively. This integration process is required to be automatic, fast, accurate and robust; however inter-modal image registration is difficult due to the lack of a direct relationship between the intensities of the two image sets. To address this problem, Computed Tomography (CT) was used to acquire pre-operative images and Ultrasound (US) was used to acquire peri-operative images. Since bone has a high electron density and is highly echogenic, the rib cage is visualized as a bright white boundary in both datasets. The proposed approach utilizes the ribs as the basis for an intensity-based registration method -- mutual information. We validated this approach using a thorax phantom. Validation results demonstrate that this approach is accurate and shows little variation between operators. The fiducial registration error, the registration error between the US and CT images, was < 1.5mm. We propose this registration method as a basis for precise tracking of minimally invasive thoracic procedures. This method will permit the planning and guidance of image-guided minimally invasive procedures for the lungs, as well as for both catheter-based and direct trans-mural interventions within the beating heart.

  19. Determining inter-fractional motion of the uterus using 3D ultrasound imaging during radiotherapy for cervical cancer

    Baker, Mariwan; Jensen, Jørgen Arendt; Behrens, Claus F.

    2014-01-01

    Uterine positional changes can reduce the accuracy of radiotherapy for cervical cancer patients. The purpose of this study was to; 1) Quantify the inter-fractional uterine displacement using a novel 3D ultrasound (US) imaging system, and 2) Compare the result with the bone match shift determined...... by Cone-Beam CT (CBCT) imaging.Five cervical cancer patients were enrolled in the study. Three of them underwent weekly CBCT imaging prior to treatment and bone match shift was applied. After treatment delivery they underwent a weekly US scan. The transabdominal scans were conducted using a Clarity US...

  20. Applicable value of real time interventional ultrasound guidance in family planning reproduction operation

    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)

  1. Displaying 3D radiation dose on endoscopic video for therapeutic assessment and surgical guidance

    We have developed a method to register and display 3D parametric data, in particular radiation dose, on two-dimensional endoscopic images. This registration of radiation dose to endoscopic or optical imaging may be valuable in assessment of normal tissue response to radiation, and visualization of radiated tissues in patients receiving post-radiation surgery. Electromagnetic sensors embedded in a flexible endoscope were used to track the position and orientation of the endoscope allowing registration of 2D endoscopic images to CT volumetric images and radiation doses planned with respect to these images. A surface was rendered from the CT image based on the air/tissue threshold, creating a virtual endoscopic view analogous to the real endoscopic view. Radiation dose at the surface or at known depth below the surface was assigned to each segment of the virtual surface. Dose could be displayed as either a colorwash on this surface or surface isodose lines. By assigning transparency levels to each surface segment based on dose or isoline location, the virtual dose display was overlaid onto the real endoscope image. Spatial accuracy of the dose display was tested using a cylindrical phantom with a treatment plan created for the phantom that matched dose levels with grid lines on the phantom surface. The accuracy of the dose display in these phantoms was 0.8–0.99 mm. To demonstrate clinical feasibility of this approach, the dose display was also tested on clinical data of a patient with laryngeal cancer treated with radiation therapy, with estimated display accuracy of ∼2–3 mm. The utility of the dose display for registration of radiation dose information to the surgical field was further demonstrated in a mock sarcoma case using a leg phantom. With direct overlay of radiation dose on endoscopic imaging, tissue toxicities and tumor response in endoluminal organs can be directly correlated with the actual tissue dose, offering a more nuanced assessment of normal

  2. Three dimensional level set based semiautomatic segmentation of atherosclerotic carotid artery wall volume using 3D ultrasound imaging

    Hossain, Md. Murad; AlMuhanna, Khalid; Zhao, Limin; Lal, Brajesh K.; Sikdar, Siddhartha

    2014-03-01

    3D segmentation of carotid plaque from ultrasound (US) images is challenging due to image artifacts and poor boundary definition. Semiautomatic segmentation algorithms for calculating vessel wall volume (VWV) have been proposed for the common carotid artery (CCA) but they have not been applied on plaques in the internal carotid artery (ICA). In this work, we describe a 3D segmentation algorithm that is robust to shadowing and missing boundaries. Our algorithm uses distance regularized level set method with edge and region based energy to segment the adventitial wall boundary (AWB) and lumen-intima boundary (LIB) of plaques in the CCA, ICA and external carotid artery (ECA). The algorithm is initialized by manually placing points on the boundary of a subset of transverse slices with an interslice distance of 4mm. We propose a novel user defined stopping surface based energy to prevent leaking of evolving surface across poorly defined boundaries. Validation was performed against manual segmentation using 3D US volumes acquired from five asymptomatic patients with carotid stenosis using a linear 4D probe. A pseudo gold-standard boundary was formed from manual segmentation by three observers. The Dice similarity coefficient (DSC), Hausdor distance (HD) and modified HD (MHD) were used to compare the algorithm results against the pseudo gold-standard on 1205 cross sectional slices of 5 3D US image sets. The algorithm showed good agreement with the pseudo gold standard boundary with mean DSC of 93.3% (AWB) and 89.82% (LIB); mean MHD of 0.34 mm (AWB) and 0.24 mm (LIB); mean HD of 1.27 mm (AWB) and 0.72 mm (LIB). The proposed 3D semiautomatic segmentation is the first step towards full characterization of 3D plaque progression and longitudinal monitoring.

  3. Conformal needle-based ultrasound ablation using EM-tracked conebeam CT image guidance

    Burdette, E. Clif; Banovac, Filip; Diederich, Chris J.; Cheng, Patrick; Wilson, Emmanuel; Cleary, Kevin R.

    2011-03-01

    liver were 73cc, 84cc, and 140cc for 3, 4, and 5 placements, respectively. These experiments demonstrate the feasibility of combining real-time spatially tracked image guidance with directional interstitial ultrasound ablation. Interstitial ultrasound ablation delivered on multiple needles permit the size and shape of the ablation zone to be "sculpted" by modifying the angle and intensity of the active US elements in the array. This paper summarizes the design and development of the first system incorporating thermal treatment planning and integration of a novel interstitial acoustic ablation device with integrated 3D electromagnetic tracking and guidance strategy.

  4. Non-Invasive Targeted Peripheral Nerve Ablation Using 3D MR Neurography and MRI-Guided High-Intensity Focused Ultrasound (MR-HIFU): Pilot Study in a Swine Model

    Huisman, Merel; Staruch, Robert M.; Ladouceur-Wodzak, Michelle; van den Bosch, Maurice A.; Burns, Dennis K.; Chhabra, Avneesh; Chopra, Rajiv

    2015-01-01

    Purpose Ultrasound (US)-guided high intensity focused ultrasound (HIFU) has been proposed for noninvasive treatment of neuropathic pain and has been investigated in in-vivo studies. However, ultrasound has important limitations regarding treatment guidance and temperature monitoring. Magnetic resonance (MR)-imaging guidance may overcome these limitations and MR-guided HIFU (MR-HIFU) has been used successfully for other clinical indications. The primary purpose of this study was to evaluate the feasibility of utilizing 3D MR neurography to identify and guide ablation of peripheral nerves using a clinical MR-HIFU system. Methods Volumetric MR-HIFU was used to induce lesions in the peripheral nerves of the lower limbs in three pigs. Diffusion-prep MR neurography and T1-weighted images were utilized to identify the target, plan treatment and immediate post-treatment evaluation. For each treatment, one 8 or 12 mm diameter treatment cell was used (sonication duration 20 s and 36 s, power 160–300 W). Peripheral nerves were extracted HIFU. Diffusion-prep 3D MR neurography has potential for guiding therapy procedures where either nerve targeting or avoidance is desired, and may also have potential for post-treatment verification of thermal lesions without contrast injection. PMID:26659073

  5. Ultrasound Guidance for Deep Peripheral Nerve Blocks: A Brief Review

    Detlef Obal; Ralf Erich Gebhard; Sujittra Tongpresert; Sunitha Kanchi Kandadai; Anupama Wadhwa

    2011-01-01

    Nerve stimulation and ultrasound have been introduced to the practice of regional anesthesia mostly in the last two decades. Ultrasound did not gain as much popularity as the nerve stimulation until a decade ago because of the simplicity, accuracy and portability of the nerve stimulator. Ultrasound is now available in most academic centers practicing regional anesthesia and is a popular tool amongst trainees for performance of nerve blocks. This review article specifically discusses the role ...

  6. Engineering a 3D ultrasound system for image-guided vascular modelling

    Hammer, Steven James

    2009-01-01

    Atherosclerosis is often diagnosed using an ultrasound (US) examination in the carotid and femoral arteries and the abdominal aorta. A decision to operate requires two measures of disease severity: the degree of stenosis measured using B-mode US; and the blood flow patterns in the artery measured using spectral Doppler US. However other biomechanical factors such as wall shear stress (WSS) and areas of flow recirculation are also important in disease development and rupture. Th...

  7. A computational model for estimating tumor margins in complementary tactile and 3D ultrasound images

    Shamsil, Arefin; Escoto, Abelardo; Naish, Michael D.; Patel, Rajni V.

    2016-03-01

    Conventional surgical methods are effective for treating lung tumors; however, they impose high trauma and pain to patients. Minimally invasive surgery is a safer alternative as smaller incisions are required to reach the lung; however, it is challenging due to inadequate intraoperative tumor localization. To address this issue, a mechatronic palpation device was developed that incorporates tactile and ultrasound sensors capable of acquiring surface and cross-sectional images of palpated tissue. Initial work focused on tactile image segmentation and fusion of position-tracked tactile images, resulting in a reconstruction of the palpated surface to compute the spatial locations of underlying tumors. This paper presents a computational model capable of analyzing orthogonally-paired tactile and ultrasound images to compute the surface circumference and depth margins of a tumor. The framework also integrates an error compensation technique and an algebraic model to align all of the image pairs and to estimate the tumor depths within the tracked thickness of a palpated tissue. For validation, an ex vivo experimental study was conducted involving the complete palpation of 11 porcine liver tissues injected with iodine-agar tumors of varying sizes and shapes. The resulting tactile and ultrasound images were then processed using the proposed model to compute the tumor margins and compare them to fluoroscopy based physical measurements. The results show a good negative correlation (r = -0.783, p = 0.004) between the tumor surface margins and a good positive correlation (r = 0.743, p = 0.009) between the tumor depth margins.

  8. SU-E-J-135: An Investigation of Ultrasound Imaging for 3D Intra-Fraction Prostate Motion Estimation

    Purpose: This study investigates the use of a mechanically swept 3D ultrasound (US) probe to estimate intra-fraction motion of the prostate during radiation therapy using an US phantom and simulated transperineal imaging. Methods: A 3D motion platform was used to translate an US speckle phantom while simulating transperineal US imaging. Motion patterns for five representative types of prostate motion, generated from patient data previously acquired with a Calypso system, were using to move the phantom in 3D. The phantom was also implanted with fiducial markers and subsequently tracked using the CyberKnife kV x-ray system for comparison. A normalised cross correlation block matching algorithm was used to track speckle patterns in 3D and 2D US data. Motion estimation results were compared with known phantom translations. Results: Transperineal 3D US could track superior-inferior (axial) and anterior-posterior (lateral) motion to better than 0.8 mm root-mean-square error (RMSE) at a volume rate of 1.7 Hz (comparable with kV x-ray tracking RMSE). Motion estimation accuracy was poorest along the US probe's swept axis (right-left; RL; RMSE < 4.2 mm) but simple regularisation methods could be used to improve RMSE (< 2 mm). 2D US was found to be feasible for slowly varying motion (RMSE < 0.5 mm). 3D US could also allow accurate radiation beam gating with displacement thresholds of 2 mm and 5 mm exhibiting a RMSE of less than 0.5 mm. Conclusion: 2D and 3D US speckle tracking is feasible for prostate motion estimation during radiation delivery. Since RL prostate motion is small in magnitude and frequency, 2D or a hybrid (2D/3D) US imaging approach which also accounts for potential prostate rotations could be used. Regularisation methods could be used to ensure the accuracy of tracking data, making US a feasible approach for gating or tracking in standard or hypo-fractionated prostate treatments

  9. Ultrasound Guidance for Deep Peripheral Nerve Blocks: A Brief Review

    Anupama Wadhwa

    2011-01-01

    Full Text Available Nerve stimulation and ultrasound have been introduced to the practice of regional anesthesia mostly in the last two decades. Ultrasound did not gain as much popularity as the nerve stimulation until a decade ago because of the simplicity, accuracy and portability of the nerve stimulator. Ultrasound is now available in most academic centers practicing regional anesthesia and is a popular tool amongst trainees for performance of nerve blocks. This review article specifically discusses the role of ultrasonography for deeply situated nerves or plexuses such as the infraclavicular block for the upper extremity and lumbar plexus and sciatic nerve blocks for the lower extremity. Transitioning from nerve stimulation to ultrasound-guided blocks alone or in combination is beneficial in certain scenarios. However, not every patient undergoing regional anesthesia technique benefits from the use of ultrasound, especially when circumstances resulting in difficult visualization such as deep nerve blocks and/or block performed by inexperienced ultrasonographers. The use of ultrasound does not replace experience and knowledge of relevant anatomy, especially for visualization of deep structures. In certain scenarios, ultrasound may not offer additional value and substantial amount of time may be spent trying to find relevant structures or even provide a false sense of security, especially to an inexperienced operator. We look at available literature on the role of ultrasound for the performance of deep peripheral nerve blocks and its benefits.

  10. Ultrasound Guidance for Deep Peripheral Nerve Blocks: A Brief Review

    Wadhwa, Anupama; Kandadai, Sunitha Kanchi; Tongpresert, Sujittra; Obal, Detlef; Gebhard, Ralf Erich

    2011-01-01

    Nerve stimulation and ultrasound have been introduced to the practice of regional anesthesia mostly in the last two decades. Ultrasound did not gain as much popularity as the nerve stimulation until a decade ago because of the simplicity, accuracy and portability of the nerve stimulator. Ultrasound is now available in most academic centers practicing regional anesthesia and is a popular tool amongst trainees for performance of nerve blocks. This review article specifically discusses the role of ultrasonography for deeply situated nerves or plexuses such as the infraclavicular block for the upper extremity and lumbar plexus and sciatic nerve blocks for the lower extremity. Transitioning from nerve stimulation to ultrasound-guided blocks alone or in combination is beneficial in certain scenarios. However, not every patient undergoing regional anesthesia technique benefits from the use of ultrasound, especially when circumstances resulting in difficult visualization such as deep nerve blocks and/or block performed by inexperienced ultrasonographers. The use of ultrasound does not replace experience and knowledge of relevant anatomy, especially for visualization of deep structures. In certain scenarios, ultrasound may not offer additional value and substantial amount of time may be spent trying to find relevant structures or even provide a false sense of security, especially to an inexperienced operator. We look at available literature on the role of ultrasound for the performance of deep peripheral nerve blocks and its benefits. PMID:21808644

  11. In vivo validation of a 3D ultrasound system for imaging the lateral ventricles of neonates

    Kishimoto, J.; Fenster, A.; Chen, N.; Lee, D.; de Ribaupierre, S.

    2014-03-01

    Dilated lateral ventricles in neonates can be due to many different causes, such as brain loss, or congenital malformation; however, the main cause is hydrocephalus, which is the accumulation of fluid within the ventricular system. Hydrocephalus can raise intracranial pressure resulting in secondary brain damage, and up to 25% of patients with severely enlarged ventricles have epilepsy in later life. Ventricle enlargement is clinically monitored using 2D US through the fontanels. The sensitivity of 2D US to dilation is poor because it cannot provide accurate measurements of irregular volumes such as the ventricles, so most clinical evaluations are of a qualitative nature. We developed a 3D US system to image the cerebral ventricles of neonates within the confines of incubators that can be easily translated to more open environments. Ventricle volumes can be segmented from these images giving a quantitative volumetric measurement of ventricle enlargement without moving the patient into an imaging facility. In this paper, we report on in vivo validation studies: 1) comparing 3D US ventricle volumes before and after clinically necessary interventions removing CSF, and 2) comparing 3D US ventricle volumes to those from MRI. Post-intervention ventricle volumes were less than pre-intervention measurements for all patients and all interventions. We found high correlations (R = 0.97) between the difference in ventricle volume and the reported removed CSF with the slope not significantly different than 1 (p MR images taken 4 (±3.8) days of each other did not show significant difference (p=0.44) between 3D US and MRI through paired t-test.

  12. The Correlation Between the GFR and the Renal Dimensions in Glomerulopathy Patients: Comparison of 2D and 3D Ultrasound

    We wanted to determine the correlation between the renal length as measured on two dimensional (2D) ultrasonography (US) and the renal parenchymal volume as measured with a new three-dimensional (3D) volume probe ultrasound system. We also wanted to determine the correlation between the renal length or renal parenchymal volume and the glomerular filtration rate (GFR) in patients with glomerulopathy. From July 2007 to December 2007, 26 patients who were pathologically confirmed to have glomerulopathy by biopsy were enrolled. Renal length was measured with 2D US and the renal parenchymal volume was measured with 3D US just prior to biopsy. The GFR was obtained from the electronic medical records. Pearson's correlation coefficients were used to analyze the correlation between the renal length and the renal parenchymal volume, the correlation between the renal length and the GFR and the correlation between the renal parenchymal volume and the GFR. The renal length and the renal parenchymal volume showed strong positive correlation (r = 0.850, p = 0.0001). The correlation coefficient between the renal length and the GFR was 0.623 (p = 0.0007) and the correlation coefficient between the renal volume and the GFR was 0.590 (p = 0.0015). Both the renal length and renal parenchymal volume showed apparently positive correlations with the GFR in glomerulopathy patients. The renal length showed strong positive correlations with the renal parenchymal volume. Both the renal length and the renal parenchymal volume showed apparently positive correlations with the GFR in glomerulopathy patients. In glomerulopathy patients, the renal dimensions measured by ultrasound can reflect the status of the GFR, and the measurement of the 2D renal length could be sufficient for follow up. Further studies are needed to evaluate the role of 3D US for assessing patients with renal disease

  13. A simulator for percutaneous hepatic microwave thermal ablation under ultrasound guidance.

    Wu, Wenbo; Xue, Yingfeng; Wang, Dong; Xue, Jin; Zhai, Weiming; Liang, Ping

    2014-11-01

    The purpose of this study was to provide a simulation therapy environment for microwave thermal ablation (MWA) under the guidance of ultrasound, and to present an inexpensive and portable simulator built on real patient-based pre-operative computed tomography (CT) data. We established an experimental simulation system for teaching MWA and present the results of a preliminary evaluation of the simulator's realism and utility for training. The system comprises physical elements of an electromagnetic tracking device and an abdominal phantom, and software elements providing three-dimensional (3D) image processing tools, real-time navigation functions and objective evaluation function module. Details of the novel aspects of this system are presented, including a portable electromagnetic tracking device, adoption of real patient-based pre-operative CT data of liver, operation simulation of MWA, and recording and playback of the operation simulation. Patients with liver cancer were selected for evaluation of the clinical application value of the experimental simulation system. A total of 50 consultant interventional radiologists and 20 specialist registrars in radiology rated the simulator's hardware reality and overall ergonomics. Results show that the simulator system we describe can be used as a training tool for MWA. It enables training with real patient cases prior to surgery, and it can provide a realistic simulation of the actual procedure. PMID:25296705

  14. Estimating 3D lumen centerlines of carotid arteries in free-hand acquisition ultrasound

    Carvalho, D.D.B.; Klein, S.; Z. Akkus; Ten Kate, G.L.; Schinkel, A F L; Bosch, J.G.; van der Lugt, A.; Niessen, W.J.

    2011-01-01

    Purpose The purpose of this paper is to present a methodology to estimate the carotid artery lumen centerlines in ultrasound (US) images obtained in a free-hand examination. Challenging aspects here are speckle noise in US images, artifacts, and the lack of contrast in the direction orthogonal to the US beam direction. Method An algorithm based on a rough lumen segmentation obtained by robust ellipse fitting was developed to deal with these conditions and estimate the lumen center in 2D B-mod...

  15. Adaptation of a 3D prostate cancer atlas for transrectal ultrasound guided target-specific biopsy

    Due to lack of imaging modalities to identify prostate cancer in vivo, current TRUS guided prostate biopsies are taken randomly. Consequently, many important cancers are missed during initial biopsies. The purpose of this study was to determine the potential clinical utility of a high-speed registration algorithm for a 3D prostate cancer atlas. This 3D prostate cancer atlas provides voxel-level likelihood of cancer and optimized biopsy locations on a template space (Zhan et al 2007). The atlas was constructed from 158 expert annotated, 3D reconstructed radical prostatectomy specimens outlined for cancers (Shen et al 2004). For successful clinical implementation, the prostate atlas needs to be registered to each patient's TRUS image with high registration accuracy in a time-efficient manner. This is implemented in a two-step procedure, the segmentation of the prostate gland from a patient's TRUS image followed by the registration of the prostate atlas. We have developed a fast registration algorithm suitable for clinical applications of this prostate cancer atlas. The registration algorithm was implemented on a graphical processing unit (GPU) to meet the critical processing speed requirements for atlas guided biopsy. A color overlay of the atlas superposed on the TRUS image was presented to help pick statistically likely regions known to harbor cancer. We validated our fast registration algorithm using computer simulations of two optimized 7- and 12-core biopsy protocols to maximize the overall detection rate. Using a GPU, patient's TRUS image segmentation and atlas registration took less than 12 s. The prostate cancer atlas guided 7- and 12-core biopsy protocols had cancer detection rates of 84.81% and 89.87% respectively when validated on the same set of data. Whereas the sextant biopsy approach without the utility of 3D cancer atlas detected only 70.5% of the cancers using the same histology data. We estimate 10-20% increase in prostate cancer detection rates

  16. Adaptation of a 3D prostate cancer atlas for transrectal ultrasound guided target-specific biopsy

    Narayanan, R; Suri, J S [Eigen Inc, Grass Valley, CA (United States); Werahera, P N; Barqawi, A; Crawford, E D [University of Colorado, Denver, CO (United States); Shinohara, K [University of California, San Francisco, CA (United States); Simoneau, A R [University of California, Irvine, CA (United States)], E-mail: jas.suri@eigen.com

    2008-10-21

    Due to lack of imaging modalities to identify prostate cancer in vivo, current TRUS guided prostate biopsies are taken randomly. Consequently, many important cancers are missed during initial biopsies. The purpose of this study was to determine the potential clinical utility of a high-speed registration algorithm for a 3D prostate cancer atlas. This 3D prostate cancer atlas provides voxel-level likelihood of cancer and optimized biopsy locations on a template space (Zhan et al 2007). The atlas was constructed from 158 expert annotated, 3D reconstructed radical prostatectomy specimens outlined for cancers (Shen et al 2004). For successful clinical implementation, the prostate atlas needs to be registered to each patient's TRUS image with high registration accuracy in a time-efficient manner. This is implemented in a two-step procedure, the segmentation of the prostate gland from a patient's TRUS image followed by the registration of the prostate atlas. We have developed a fast registration algorithm suitable for clinical applications of this prostate cancer atlas. The registration algorithm was implemented on a graphical processing unit (GPU) to meet the critical processing speed requirements for atlas guided biopsy. A color overlay of the atlas superposed on the TRUS image was presented to help pick statistically likely regions known to harbor cancer. We validated our fast registration algorithm using computer simulations of two optimized 7- and 12-core biopsy protocols to maximize the overall detection rate. Using a GPU, patient's TRUS image segmentation and atlas registration took less than 12 s. The prostate cancer atlas guided 7- and 12-core biopsy protocols had cancer detection rates of 84.81% and 89.87% respectively when validated on the same set of data. Whereas the sextant biopsy approach without the utility of 3D cancer atlas detected only 70.5% of the cancers using the same histology data. We estimate 10-20% increase in prostate cancer

  17. Optimal transcostal high-intensity focused ultrasound with combined real-time 3D movement tracking and correction

    Marquet, F.; Aubry, J. F.; Pernot, M.; Fink, M.; Tanter, M.

    2011-11-01

    Recent studies have demonstrated the feasibility of transcostal high intensity focused ultrasound (HIFU) treatment in liver. However, two factors limit thermal necrosis of the liver through the ribs: the energy deposition at focus is decreased by the respiratory movement of the liver and the energy deposition on the skin is increased by the presence of highly absorbing bone structures. Ex vivo ablations were conducted to validate the feasibility of a transcostal real-time 3D movement tracking and correction mode. Experiments were conducted through a chest phantom made of three human ribs immersed in water and were placed in front of a 300 element array working at 1 MHz. A binarized apodization law introduced recently in order to spare the rib cage during treatment has been extended here with real-time electronic steering of the beam. Thermal simulations have been conducted to determine the steering limits. In vivo 3D-movement detection was performed on pigs using an ultrasonic sequence. The maximum error on the transcostal motion detection was measured to be 0.09 ± 0.097 mm on the anterior-posterior axis. Finally, a complete sequence was developed combining real-time 3D transcostal movement correction and spiral trajectory of the HIFU beam, allowing the system to treat larger areas with optimized efficiency. Lesions as large as 1 cm in diameter have been produced at focus in excised liver, whereas no necroses could be obtained with the same emitted power without correcting the movement of the tissue sample.

  18. Segmentation of the lumen and media-adventitia boundaries of the common carotid artery from 3D ultrasound images

    Ukwatta, E.; Awad, J.; Ward, A. D.; Samarabandu, J.; Krasinski, A.; Parraga, G.; Fenster, A.

    2011-03-01

    Three-dimensional ultrasound (3D US) vessel wall volume (VWV) measurements provide high measurement sensitivity and reproducibility for the monitoring and assessment of carotid atherosclerosis. In this paper, we describe a semiautomated approach based on the level set method to delineate the media-adventitia and lumen boundaries of the common carotid artery from 3D US images to support the computation of VWV. Due to the presence of plaque and US image artifacts, the carotid arteries are challenging to segment using image information alone. Our segmentation framework combines several image cues with domain knowledge and limited user interaction. Our method was evaluated with respect to manually outlined boundaries on 430 2D US images extracted from 3D US images of 30 patients who have carotid stenosis of 60% or more. The VWV given by our method differed from that given by manual segmentation by 6.7% +/- 5.0%. For the media-adventitia and lumen segmentations, respectively, our method yielded Dice coefficients of 95.2% +/- 1.6%, 94.3% +/- 2.6%, mean absolute distances of 0.3 +/- 0.1 mm, 0.2 +/- 0.1 mm, maximum absolute distances of 0.8 +/- 0.4 mm, 0.6 +/- 0.3 mm, and volume differences of 4.2% +/- 3.1%, 3.4% +/- 2.6%. The realization of a semi-automated segmentation method will accelerate the translation of 3D carotid US to clinical care for the rapid, non-invasive, and economical monitoring of atherosclerotic disease progression and regression during therapy.

  19. Linearity of patient positioning detection. A phantom study of skin markers, cone beam computed tomography, and 3D ultrasound

    Ballhausen, Hendrik; Hieber, Sheila; Li, Minglun; Belka, Claus; Reiner, Michael [University Hospital of LMU, Department of Radiation Oncology, Munich (Germany); Parodi, Katia [Ludwig-Maximilian-University, Department of Experimental Physics - Medical Physics, Munich (Germany)

    2015-05-01

    Three-dimensional ultrasound (3D-US) is a modality complementary to kilovoltage cone beam computed tomography (kV-CBCT) and skin markers for patient positioning detection. This study compares the linearity of evaluations based on measurements using a modern 3D-US system (Elekta Clarity {sup registered}; Elekta, Stockholm, Sweden), a kV-CBCT system (Elekta iView {sup registered}), and skin markers. An investigator deliberately displaced a multimodal phantom by up to ± 30 mm along different axes. The following data points were acquired: 27 along the lateral axis, 29 along the longitudinal axis, 27 along the vertical axis, and 27 along the space diagonal. At each of these 110 positions, the displacements according to skin' markers were recorded and scans were performed using both 3D-US and kV-CBCT. Shifts were detected by matching bony anatomy or soft tissue density to a reference planning CT in the case of kV-CBCT and for 3D-US, by matching ultrasound volume data to a reference planning volume. A consensus value was calculated from the average of the four modalities. With respect to this consensus value, the linearity (offset and regression coefficient, i.e., slope), average offset, systematic error, and random error of all four modalities were calculated for each axis. Linearity was similar for all four modalities, with regression coefficients between 0.994 and 1.012, and all offsets below 1 mm. The systematic errors of skin markers and 3D-US were higher than for kV-CBCT, but random errors were similar. In particular, 3D-US demonstrated an average offset of 0.36 mm to the right, 0.08 mm inferiorly, and 0.15 mm anteriorly; the systematic error was 0.36 mm laterally, 0.35 mm longitudinally, and 0.22 mm vertically; the random error was 0.15 mm laterally, 0.30 mm longitudinally, and 0.12 mm vertically. A total of 109 out of 110 (99 %) 3D-US measurements were within 1 mm of the consensus value on either axis. The linearity of 3D-US was no worse than that of skin

  20. 3D optical imagery for motion compensation in a limb ultrasound system

    Ranger, Bryan J.; Feigin, Micha; Zhang, Xiang; Mireault, Al; Raskar, Ramesh; Herr, Hugh M.; Anthony, Brian W.

    2016-04-01

    Conventional processes for prosthetic socket fabrication are heavily subjective, often resulting in an interface to the human body that is neither comfortable nor completely functional. With nearly 100% of amputees reporting that they experience discomfort with the wearing of their prosthetic limb, designing an effective interface to the body can significantly affect quality of life and future health outcomes. Active research in medical imaging and biomechanical tissue modeling of residual limbs has led to significant advances in computer aided prosthetic socket design, demonstrating an interest in moving toward more quantifiable processes that are still patient-specific. In our work, medical ultrasonography is being pursued to acquire data that may quantify and improve the design process and fabrication of prosthetic sockets while greatly reducing cost compared to an MRI-based framework. This paper presents a prototype limb imaging system that uses a medical ultrasound probe, mounted to a mechanical positioning system and submerged in a water bath. The limb imaging is combined with three-dimensional optical imaging for motion compensation. Images are collected circumferentially around the limb and combined into cross-sectional axial image slices, resulting in a compound image that shows tissue distributions and anatomical boundaries similar to magnetic resonance imaging. In this paper we provide a progress update on our system development, along with preliminary results as we move toward full volumetric imaging of residual limbs for prosthetic socket design. This demonstrates a novel multi-modal approach to residual limb imaging.

  1. Non-invasive transcranial ultrasound therapy based on a 3D CT scan: protocol validation and in vitro results

    Marquet, F; Pernot, M; Aubry, J-F; Montaldo, G; Tanter, M; Fink, M [Laboratoire Ondes et Acoustique, ESPCI, Universite Paris VII, UMR CNRS 7587, 10 rue Vauquelin, 75005 Paris (France); Marsac, L [Supersonic Imagine, Les Jardins de la Duranne, 510 rue Rene Descartes, 13857 Aix-en-Provence (France)], E-mail: fabrice.marquet@espci.org

    2009-05-07

    A non-invasive protocol for transcranial brain tissue ablation with ultrasound is studied and validated in vitro. The skull induces strong aberrations both in phase and in amplitude, resulting in a severe degradation of the beam shape. Adaptive corrections of the distortions induced by the skull bone are performed using a previous 3D computational tomography scan acquisition (CT) of the skull bone structure. These CT scan data are used as entry parameters in a FDTD (finite differences time domain) simulation of the full wave propagation equation. A numerical computation is used to deduce the impulse response relating the targeted location and the ultrasound therapeutic array, thus providing a virtual time-reversal mirror. This impulse response is then time-reversed and transmitted experimentally by a therapeutic array positioned exactly in the same referential frame as the one used during CT scan acquisitions. In vitro experiments are conducted on monkey and human skull specimens using an array of 300 transmit elements working at a central frequency of 1 MHz. These experiments show a precise refocusing of the ultrasonic beam at the targeted location with a positioning error lower than 0.7 mm. The complete validation of this transcranial adaptive focusing procedure paves the way to in vivo animal and human transcranial HIFU investigations.

  2. Non-invasive transcranial ultrasound therapy based on a 3D CT scan: protocol validation and in vitro results

    A non-invasive protocol for transcranial brain tissue ablation with ultrasound is studied and validated in vitro. The skull induces strong aberrations both in phase and in amplitude, resulting in a severe degradation of the beam shape. Adaptive corrections of the distortions induced by the skull bone are performed using a previous 3D computational tomography scan acquisition (CT) of the skull bone structure. These CT scan data are used as entry parameters in a FDTD (finite differences time domain) simulation of the full wave propagation equation. A numerical computation is used to deduce the impulse response relating the targeted location and the ultrasound therapeutic array, thus providing a virtual time-reversal mirror. This impulse response is then time-reversed and transmitted experimentally by a therapeutic array positioned exactly in the same referential frame as the one used during CT scan acquisitions. In vitro experiments are conducted on monkey and human skull specimens using an array of 300 transmit elements working at a central frequency of 1 MHz. These experiments show a precise refocusing of the ultrasonic beam at the targeted location with a positioning error lower than 0.7 mm. The complete validation of this transcranial adaptive focusing procedure paves the way to in vivo animal and human transcranial HIFU investigations.

  3. Non-invasive transcranial ultrasound therapy based on a 3D CT scan: protocol validation and in vitro results

    Marquet, F.; Pernot, M.; Aubry, J.-F.; Montaldo, G.; Marsac, L.; Tanter, M.; Fink, M.

    2009-05-01

    A non-invasive protocol for transcranial brain tissue ablation with ultrasound is studied and validated in vitro. The skull induces strong aberrations both in phase and in amplitude, resulting in a severe degradation of the beam shape. Adaptive corrections of the distortions induced by the skull bone are performed using a previous 3D computational tomography scan acquisition (CT) of the skull bone structure. These CT scan data are used as entry parameters in a FDTD (finite differences time domain) simulation of the full wave propagation equation. A numerical computation is used to deduce the impulse response relating the targeted location and the ultrasound therapeutic array, thus providing a virtual time-reversal mirror. This impulse response is then time-reversed and transmitted experimentally by a therapeutic array positioned exactly in the same referential frame as the one used during CT scan acquisitions. In vitro experiments are conducted on monkey and human skull specimens using an array of 300 transmit elements working at a central frequency of 1 MHz. These experiments show a precise refocusing of the ultrasonic beam at the targeted location with a positioning error lower than 0.7 mm. The complete validation of this transcranial adaptive focusing procedure paves the way to in vivo animal and human transcranial HIFU investigations.

  4. Three different strategies for real-time prostate capsule volume computation from 3-D end-fire transrectal ultrasound.

    Barqawi, Albaha B; Lu, Li; Crawford, E David; Fenster, Aaron; Werahera, Priya N; Kumar, Dinesh; Miller, Steve; Suri, Jasjit S

    2007-01-01

    estimation of prostate capsule volume via segmentation of the prostate from 3-D ultrasound volumetric ultrasound images is a valuable clinical tool, especially during biopsy. Normally, a physician traces the boundaries of the prostate manually, but this process is tedious, laborious, and subject to errors. The prostate capsule edge is computed using three different strategies: (a) least square approach, (b) level set approach, and (c) Discrete Dynamic Contour approach. (a) In the least square method, edge points are defined by searching for the optimal edge based on the average signal characteristics. These edge points constitute an initial curve which is later refined; (b) Level set approach. The images are modeled as piece-wise constant, and the energy functional is defined and minimized. This method is also automated; and (c) The Discrete Dynamic Contour (DDC). A trained user selects several points in the first image and an initial contour is obtained by a model based initialization. Based on this initialization condition, the contour is deformed automatically to better fit the image. This method is semi-automatic. The three methods were tested on database consisting of 15 prostate phantom volumes acquired using a Philips ultrasound machine using an end-fire TRUS. The ground truth (GT) is developed by tracing the boundary of prostate on a slice-by-slice basis. The mean volumes using the least square, level set and DDC techniques were 15.84 cc, 15.55 cc and 16.33 cc, respectively. We validated the methods by calculating the volume with GT and we got an average volume of 15. PMID:18002081

  5. Automatic segmentation and 3D reconstruction of intravascular ultrasound images for a fast preliminar evaluation of vessel pathologies.

    Sanz-Requena, Roberto; Moratal, David; García-Sánchez, Diego Ramón; Bodí, Vicente; Rieta, José Joaquín; Sanchis, Juan Manuel

    2007-03-01

    Intravascular ultrasound (IVUS) imaging is used along with X-ray coronary angiography to detect vessel pathologies. Manual analysis of IVUS images is slow and time-consuming and it is not feasible for clinical purposes. A semi-automated method is proposed to generate 3D reconstructions from IVUS video sequences, so that a fast diagnose can be easily done, quantifying plaque length and severity as well as plaque volume of the vessels under study. The methodology described in this work has four steps: a pre-processing of IVUS images, a segmentation of media-adventitia contour, a detection of intima and plaque and a 3D reconstruction of the vessel. Preprocessing is intended to remove noise from the images without blurring the edges. Segmentation of media-adventitia contour is achieved using active contours (snakes). In particular, we use the gradient vector flow (GVF) as external force for the snakes. The detection of lumen border is obtained taking into account gray-level information of the inner part of the previously detected contours. A knowledge-based approach is used to determine which level of gray corresponds statistically to the different regions of interest: intima, plaque and lumen. The catheter region is automatically discarded. An estimate of plaque type is also given. Finally, 3D reconstruction of all detected regions is made. The suitability of this methodology has been verified for the analysis and visualization of plaque length, stenosis severity, automatic detection of the most problematic regions, calculus of plaque volumes and a preliminary estimation of plaque type obtaining for automatic measures of lumen and vessel area an average error smaller than 1mm(2) (equivalent aproximately to 10% of the average measure), for calculus of plaque and lumen volume errors smaller than 0.5mm(3) (equivalent approximately to 20% of the average measure) and for plaque type estimates a mismatch of less than 8% in the analysed frames. PMID:17215103

  6. Airport databases for 3D synthetic-vision flight-guidance displays: database design, quality assessment, and data generation

    Friedrich, Axel; Raabe, Helmut; Schiefele, Jens; Doerr, Kai Uwe

    1999-07-01

    In future aircraft cockpit designs SVS (Synthetic Vision System) databases will be used to display 3D physical and virtual information to pilots. In contrast to pure warning systems (TAWS, MSAW, EGPWS) SVS serve to enhance pilot spatial awareness by 3-dimensional perspective views of the objects in the environment. Therefore all kind of aeronautical relevant data has to be integrated into the SVS-database: Navigation- data, terrain-data, obstacles and airport-Data. For the integration of all these data the concept of a GIS (Geographical Information System) based HQDB (High-Quality- Database) has been created at the TUD (Technical University Darmstadt). To enable database certification, quality- assessment procedures according to ICAO Annex 4, 11, 14 and 15 and RTCA DO-200A/EUROCAE ED76 were established in the concept. They can be differentiated in object-related quality- assessment-methods following the keywords accuracy, resolution, timeliness, traceability, assurance-level, completeness, format and GIS-related quality assessment methods with the keywords system-tolerances, logical consistence and visual quality assessment. An airport database is integrated in the concept as part of the High-Quality- Database. The contents of the HQDB are chosen so that they support both Flight-Guidance-SVS and other aeronautical applications like SMGCS (Surface Movement and Guidance Systems) and flight simulation as well. Most airport data are not available. Even though data for runways, threshold, taxilines and parking positions were to be generated by the end of 1997 (ICAO Annex 11 and 15) only a few countries fulfilled these requirements. For that reason methods of creating and certifying airport data have to be found. Remote sensing and digital photogrammetry serve as means to acquire large amounts of airport objects with high spatial resolution and accuracy in much shorter time than with classical surveying methods. Remotely sensed images can be acquired from satellite

  7. Magnetic resonance imaging-targeted, 3D transrectal ultrasound-guided fusion biopsy for prostate cancer: Quantifying the impact of needle delivery error on diagnosis

    Purpose: Magnetic resonance imaging (MRI)-targeted, 3D transrectal ultrasound (TRUS)-guided “fusion” prostate biopsy intends to reduce the ∼23% false negative rate of clinical two-dimensional TRUS-guided sextant biopsy. Although it has been reported to double the positive yield, MRI-targeted biopsies continue to yield false negatives. Therefore, the authors propose to investigate how biopsy system needle delivery error affects the probability of sampling each tumor, by accounting for uncertainties due to guidance system error, image registration error, and irregular tumor shapes. Methods: T2-weighted, dynamic contrast-enhanced T1-weighted, and diffusion-weighted prostate MRI and 3D TRUS images were obtained from 49 patients. A radiologist and radiology resident contoured 81 suspicious regions, yielding 3D tumor surfaces that were registered to the 3D TRUS images using an iterative closest point prostate surface-based method to yield 3D binary images of the suspicious regions in the TRUS context. The probabilityP of obtaining a sample of tumor tissue in one biopsy core was calculated by integrating a 3D Gaussian distribution over each suspicious region domain. Next, the authors performed an exhaustive search to determine the maximum root mean squared error (RMSE, in mm) of a biopsy system that gives P ≥ 95% for each tumor sample, and then repeated this procedure for equal-volume spheres corresponding to each tumor sample. Finally, the authors investigated the effect of probe-axis-direction error on measured tumor burden by studying the relationship between the error and estimated percentage of core involvement. Results: Given a 3.5 mm RMSE for contemporary fusion biopsy systems,P ≥ 95% for 21 out of 81 tumors. The authors determined that for a biopsy system with 3.5 mm RMSE, one cannot expect to sample tumors of approximately 1 cm3 or smaller with 95% probability with only one biopsy core. The predicted maximum RMSE giving P ≥ 95% for each tumor was

  8. Magnetic resonance imaging-targeted, 3D transrectal ultrasound-guided fusion biopsy for prostate cancer: Quantifying the impact of needle delivery error on diagnosis

    Martin, Peter R., E-mail: pmarti46@uwo.ca [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Cool, Derek W. [Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7, Canada and Robarts Research Institute, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Romagnoli, Cesare [Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Fenster, Aaron [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Department of Medical Imaging, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Robarts Research Institute, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Ward, Aaron D. [Department of Medical Biophysics, The University of Western Ontario, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, London, Ontario N6A 3K7 (Canada)

    2014-07-15

    Purpose: Magnetic resonance imaging (MRI)-targeted, 3D transrectal ultrasound (TRUS)-guided “fusion” prostate biopsy intends to reduce the ∼23% false negative rate of clinical two-dimensional TRUS-guided sextant biopsy. Although it has been reported to double the positive yield, MRI-targeted biopsies continue to yield false negatives. Therefore, the authors propose to investigate how biopsy system needle delivery error affects the probability of sampling each tumor, by accounting for uncertainties due to guidance system error, image registration error, and irregular tumor shapes. Methods: T2-weighted, dynamic contrast-enhanced T1-weighted, and diffusion-weighted prostate MRI and 3D TRUS images were obtained from 49 patients. A radiologist and radiology resident contoured 81 suspicious regions, yielding 3D tumor surfaces that were registered to the 3D TRUS images using an iterative closest point prostate surface-based method to yield 3D binary images of the suspicious regions in the TRUS context. The probabilityP of obtaining a sample of tumor tissue in one biopsy core was calculated by integrating a 3D Gaussian distribution over each suspicious region domain. Next, the authors performed an exhaustive search to determine the maximum root mean squared error (RMSE, in mm) of a biopsy system that gives P ≥ 95% for each tumor sample, and then repeated this procedure for equal-volume spheres corresponding to each tumor sample. Finally, the authors investigated the effect of probe-axis-direction error on measured tumor burden by studying the relationship between the error and estimated percentage of core involvement. Results: Given a 3.5 mm RMSE for contemporary fusion biopsy systems,P ≥ 95% for 21 out of 81 tumors. The authors determined that for a biopsy system with 3.5 mm RMSE, one cannot expect to sample tumors of approximately 1 cm{sup 3} or smaller with 95% probability with only one biopsy core. The predicted maximum RMSE giving P ≥ 95% for each

  9. Clinical utility of ultrasound guidance for intra-articular knee injections: a review

    Berkoff DJ

    2012-03-01

    Full Text Available David J Berkoff1, Larry E Miller2,3, Jon E Block31Department of Orthopedics, University of North Carolina School of Medicine, Chapel Hill, NC; 2Miller Scientific Consulting Inc, Arden, NC; 3The Jon Block Group, San Francisco, CA, USAAbstract: Intra-articular corticosteroid and hyaluronic acid injections provide short-term symptom amelioration for arthritic conditions involving structural damage or degenerative changes in the knee. Conventional palpation-guided anatomical injections frequently result in inaccurate needle placement into extra-articular tissue and adjacent structures. The purpose of this review was to determine the effect of ultrasound guidance on the accuracy of needle placement, clinical outcomes, and cost-effectiveness in comparison with anatomical landmark-guided intra-articular large joint injections, with particular emphasis on the knee. A total of 13 relevant studies were identified; five studied the knee, seven studied the shoulder, one used both the knee and shoulder, and none studied the hip. Ultrasound was used in seven studies; the remaining studies utilized air arthrography, fluoroscopy, magnetic resonance arthrography, or magnetic resonance imaging. Across all studies (using all imaging modalities and all joints, needle placement accuracy ranged from 63% to 100% with ultrasound and from 39% to 100% with conventional anatomical guidance. Imaging guidance improved the accuracy of intra-articular injections of the knee (96.7% versus 81.0%, P < 0.001 and shoulder (97.3% versus 65.4%, P < 0.001. In particular, ultrasound guidance of knee injections resulted in better accuracy than anatomical guidance (95.8% versus 77.8%, P < 0.001, yielding an odds ratio of 6.4 (95% confidence interval 2.9–14. Ultrasound guidance notably improves injection accuracy in the target intra-articular joint space of large joints including the knee. The enhanced injection accuracy achieved with ultrasound needle guidance directly improves

  10. Pulsed Radiofrequency Ablation Under Ultrasound Guidance for Huge Neuroma

    Kim, Young Ki; Jung, Il; Lee, Chang Hee; Kim, Se Hun; Kim, Jin Sun; Yoo, Byoung Woo

    2014-01-01

    Amputation neuroma can cause very serious, intractable pain. Many treatment modalities are suggested for painful neuroma. Pharmacologic treatment shows a limited effect on eliminating the pain, and surgical treatment has a high recurrence rate. We applied pulsed radiofrequency treatment at the neuroma stalk under ultrasonography guidance. The long-term outcome was very successful, prompting us to report this case.

  11. Evaluation of the relationship between renal function and renal volume-vascular indices using 3D power Doppler ultrasound

    Cansu, Aysegul, E-mail: drcansu@gmail.com; Kupeli, Ali; Kul, Sibel; Eyuboglu, Ilker; Oguz, Sukru; Ozturk, Mehmet Halil; Dinc, Hasan

    2014-07-15

    Purpose: To investigate the relationship between renal function and total renal volume-vascular indices using 3D power Doppler ultrasound (3DPDUS). Materials and methods: One hundred six patients with hypertensive proteinuric nephropathy (HPN) (49 male, 57 female) and 65 healthy controls (32 male, 33 female) were evaluated prospectively using 3DPDUS. Total renal volume (RV), vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were calculated using Virtual Organ Computer-aided Analysis (VOCAL). The estimated glomerular filtration rates (GFRs) of the patients with HPN and the control group were calculated. The patients with HPN were divided into two groups on the basis of GFR, normal (≥90) or reduced (<90). Differences between groups were compared using ANOVA. Correlations between GFR, renal volume and vascular indices were analyzed using Pearson's correlation analysis. Significance was set at p < 0.05. Results: The mean total RV, VI, FI and VFI values in the reduced GFR, normal GFR and control groups were RV (ml): 234.7, 280.7 and 294.6; VI: 17.6, 27.6 and 46.8; FI: 79.1, 88.7 and 93.9 and VFI: 7.1, 12.7 and 23.8. There were statistically significant differences between the groups (p < 0.001). Total RVs and vascular indices exhibited significant correlations with estimated GFR (r = 0.53–0.59, p < 0.001) Conclusion: Three-dimensional power Doppler ultrasound is a reliable predictive technique in renal function analysis.

  12. Robotic catheter cardiac ablation combining ultrasound guidance and force control

    Kesner, Samuel Benjamin; Howe, Robert D.

    2014-01-01

    Cardiac catheters allow physicians to access the inside of the heart and perform therapeutic interventions without stopping the heart or opening the chest. However, conventional manual and actuated cardiac catheters are currently unable to precisely track and manipulate the intracardiac tissue structures because of the fast tissue motion and potential for applying damaging forces. This paper addresses these challenges by proposing and implementing a robotic catheter system that uses 3D ultras...

  13. Significant acceleration of 2D-3D registration-based fusion of ultrasound and x-ray images by mesh-based DRR rendering

    Kaiser, Markus; John, Matthias; Borsdorf, Anja; Mountney, Peter; Ionasec, Razvan; Nöttling, Alois; Kiefer, Philipp; Seeburger, Jörg; Neumuth, Thomas

    2013-03-01

    For transcatheter-based minimally invasive procedures in structural heart disease ultrasound and X-ray are the two enabling imaging modalities. A live fusion of both real-time modalities can potentially improve the workflow and the catheter navigation by combining the excellent instrument imaging of X-ray with the high-quality soft tissue imaging of ultrasound. A recently published approach to fuse X-ray fluoroscopy with trans-esophageal echo (TEE) registers the ultrasound probe to X-ray images by a 2D-3D registration method which inherently provides a registration of ultrasound images to X-ray images. In this paper, we significantly accelerate the 2D-3D registration method in this context. The main novelty is to generate the projection images (DRR) of the 3D object not via volume ray-casting but instead via a fast rendering of triangular meshes. This is possible, because in the setting for TEE/X-ray fusion the 3D geometry of the ultrasound probe is known in advance and their main components can be described by triangular meshes. We show that the new approach can achieve a speedup factor up to 65 and does not affect the registration accuracy when used in conjunction with the gradient correlation similarity measure. The improvement is independent of the underlying registration optimizer. Based on the results, a TEE/X-ray fusion could be performed with a higher frame rate and a shorter time lag towards real-time registration performance. The approach could potentially accelerate other applications of 2D-3D registrations, e.g. the registration of implant models with X-ray images.

  14. Use of cone-beam CT and live 3-D needle guidance to facilitate percutaneous nephrostomy and nephrolithotripsy access in children and adolescents

    Gaining access into non-dilated renal collecting systems for percutaneous nephrolithotripsy, particularly in patients with prohibitive body habitus and/or scoliosis, is often challenging using conventional techniques. To evaluate the feasibility of cone-beam CT for percutaneous nephrostomy placement for subsequent percutaneous nephrolithotripsy in children and adolescents. A retrospective review of percutaneous nephrostomy revealed use of cone-beam CT and 3-D guidance in 12 percutaneous nephrostomy procedures for 9 patients between 2006 and 2015. All cone-beam CT-guided percutaneous nephrostomies were for pre-lithotripsy access and all 12 were placed in non-dilated collecting systems. Technical success was 100%. There were no complications. Cone-beam CT with 3-D guidance is a technically feasible technique for percutaneous nephrostomy in children and adolescents, specifically for nephrolithotripsy access in non-dilated collecting systems. (orig.)

  15. Use of cone-beam CT and live 3-D needle guidance to facilitate percutaneous nephrostomy and nephrolithotripsy access in children and adolescents

    Hawkins, C.M. [Emory University School of Medicine, Department of Radiology and Imaging Sciences, Atlanta, GA (United States); Kukreja, Kamlesh [Texas Children' s Hospital, Department of Radiology, Houston, TX (United States); Singewald, Timothy; Johnson, Neil D.; Racadio, John M. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Minevich, Eugene; Reddy, Pramod [Cincinnati Children' s Hospital Medical Center, Department of Urology, Cincinnati, OH (United States)

    2016-04-15

    Gaining access into non-dilated renal collecting systems for percutaneous nephrolithotripsy, particularly in patients with prohibitive body habitus and/or scoliosis, is often challenging using conventional techniques. To evaluate the feasibility of cone-beam CT for percutaneous nephrostomy placement for subsequent percutaneous nephrolithotripsy in children and adolescents. A retrospective review of percutaneous nephrostomy revealed use of cone-beam CT and 3-D guidance in 12 percutaneous nephrostomy procedures for 9 patients between 2006 and 2015. All cone-beam CT-guided percutaneous nephrostomies were for pre-lithotripsy access and all 12 were placed in non-dilated collecting systems. Technical success was 100%. There were no complications. Cone-beam CT with 3-D guidance is a technically feasible technique for percutaneous nephrostomy in children and adolescents, specifically for nephrolithotripsy access in non-dilated collecting systems. (orig.)

  16. Accuracy and inter-observer variability of 3D versus 4D cone-beam CT based image-guidance in SBRT for lung tumors

    Sweeney Reinhart A

    2012-06-01

    Full Text Available Abstract Background To analyze the accuracy and inter-observer variability of image-guidance (IG using 3D or 4D cone-beam CT (CBCT technology in stereotactic body radiotherapy (SBRT for lung tumors. Materials and methods Twenty-one consecutive patients treated with image-guided SBRT for primary and secondary lung tumors were basis for this study. A respiration correlated 4D-CT and planning contours served as reference for all IG techniques. Three IG techniques were performed independently by three radiation oncologists (ROs and three radiotherapy technicians (RTTs. Image-guidance using respiration correlated 4D-CBCT (IG-4D with automatic registration of the planning 4D-CT and the verification 4D-CBCT was considered gold-standard. Results were compared with two IG techniques using 3D-CBCT: 1 manual registration of the planning internal target volume (ITV contour and the motion blurred tumor in the 3D-CBCT (IG-ITV; 2 automatic registration of the planning reference CT image and the verification 3D-CBCT (IG-3D. Image quality of 3D-CBCT and 4D-CBCT images was scored on a scale of 1–3, with 1 being best and 3 being worst quality for visual verification of the IGRT results. Results Image quality was scored significantly worse for 3D-CBCT compared to 4D-CBCT: the worst score of 3 was given in 19 % and 7.1 % observations, respectively. Significant differences in target localization were observed between 4D-CBCT and 3D-CBCT based IG: compared to the reference of IG-4D, tumor positions differed by 1.9 mm ± 0.9 mm (3D vector on average using IG-ITV and by 3.6 mm ± 3.2 mm using IG-3D; results of IG-ITV were significantly closer to the reference IG-4D compared to IG-3D. Differences between the 4D-CBCT and 3D-CBCT techniques increased significantly with larger motion amplitude of the tumor; analogously, differences increased with worse 3D-CBCT image quality scores. Inter-observer variability was largest in SI direction and was

  17. Musculoskeletal ultrasound : for diagnostics and treatment guidance in the orthopaedic outpatient care

    Sunding, Kerstin

    2016-01-01

    Ultrasound (US) has shown to be of great value in diagnostics and treatment of injuries and chronic pain disorders of the musculoskeletal system. Today, it is considered to be a suitable method when investigating superficially located tendons. Another exciting field of application is the use of US for guidance of different invasive treatments. Traditionally, most diagnostic imaging have been performed at the radiologic departments but the interest for the technique at different care units, in...

  18. Method of sampling chorionic villi in first trimester of pregnancy under guidance of real time ultrasound.

    Ward, R H; Modell, B; Petrou, M; Karagözlu, F; Douratsos, E

    1983-01-01

    Samples of chorionic villi were obtained in the first trimester by aspiration using a cannula passed transcervically under the guidance of real time ultrasound. In initial studies in 47 anaesthetised patients immediately before therapeutic abortion a method was developed giving a success rate of 89%. In 10 patients successful sampling was performed as an outpatient procedure without anaesthesia. In all, seven diagnostic procedures were undertaken and four of the five unaffected pregnancies co...

  19. Quantitative Assessment of Variational Surface Reconstruction from Sparse Point Clouds in Freehand 3D Ultrasound Imaging during Image-Guided Tumor Ablation

    Shuangcheng Deng

    2016-04-01

    Full Text Available Surface reconstruction for freehand 3D ultrasound is used to provide 3D visualization of a VOI (volume of interest during image-guided tumor ablation surgery. This is a challenge because the recorded 2D B-scans are not only sparse but also non-parallel. To solve this issue, we established a framework to reconstruct the surface of freehand 3D ultrasound imaging in 2011. The key technique for surface reconstruction in that framework is based on variational interpolation presented by Greg Turk for shape transformation and is named Variational Surface Reconstruction (VSR. The main goal of this paper is to evaluate the quality of surface reconstructions, especially when the input data are extremely sparse point clouds from freehand 3D ultrasound imaging, using four methods: Ball Pivoting, Power Crust, Poisson, and VSR. Four experiments are conducted, and quantitative metrics, such as the Hausdorff distance, are introduced for quantitative assessment. The experiment results show that the performance of the proposed VSR method is the best of the four methods at reconstructing surface from sparse data. The VSR method can produce a close approximation to the original surface from as few as two contours, whereas the other three methods fail to do so. The experiment results also illustrate that the reproducibility of the VSR method is the best of the four methods.

  20. Ultrasound guidance improves the success rate of axillary plexus block: a meta-analysis

    Qin Qin

    2016-04-01

    Full Text Available ABSTRACT OBJECTIVE: To evaluate the value of real-time ultrasound (US guidance for axillary brachial plexus block (AXB through the success rate and the onset time. METHODS: The meta-analysis was carried out in the Anesthesiology Department of the Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, China. A literature search of Medline, EMBASE, Cochrane database from the years 2004 to 2014 was performed. The literature searches were carried out using medical subject headings and free-text word: "axilla", "axillary", "brachial plexus", "ultrasonography", "ultrasound", "ultrasonics". Two different reviewers carried out the search and evaluated studies independently. RESULTS: Seven randomized controlled trials, one cohort study and three retrospective studies were included. A total of 2042 patients were identified. 1157 patients underwent AXB using US guidance (US group and the controlled group included 885 patients (246 patients using traditional approach (TRAD and 639 patients using nerve stimulation (NS. Our analysis showed that the success rate was higher in the US group compared to the controlled group (90.64% vs. 82.21%, p < 0.00001. The average time to perform the block and the onset of sensory time were shorter in the US group than the controlled group. CONCLUSION: The present study demonstrated that the real-time ultrasound guidance for axillary brachial plexus block improves the success rate and reduce the mean time to onset of anesthesia and the time of block performance.

  1. Determining inter-fractional motion of the uterus using 3D ultrasound imaging during radiotherapy for cervical cancer

    Baker, Mariwan; Jensen, Jørgen Arendt; Behrens, Claus F.

    2014-03-01

    Uterine positional changes can reduce the accuracy of radiotherapy for cervical cancer patients. The purpose of this study was to; 1) Quantify the inter-fractional uterine displacement using a novel 3D ultrasound (US) imaging system, and 2) Compare the result with the bone match shift determined by Cone- Beam CT (CBCT) imaging.Five cervical cancer patients were enrolled in the study. Three of them underwent weekly CBCT imaging prior to treatment and bone match shift was applied. After treatment delivery they underwent a weekly US scan. The transabdominal scans were conducted using a Clarity US system (Clarity® Model 310C00). Uterine positional shifts based on soft-tissue match using US was performed and compared to bone match shifts for the three directions. Mean value (+/-1 SD) of the US shifts were (mm); anterior-posterior (A/P): (3.8+/-5.5), superior-inferior (S/I) (-3.5+/-5.2), and left-right (L/R): (0.4+/-4.9). The variations were larger than the CBCT shifts. The largest inter-fractional displacement was from -2 mm to +14 mm in the AP-direction for patient 3. Thus, CBCT bone matching underestimates the uterine positional displacement due to neglecting internal uterine positional change to the bone structures. Since the US images were significantly better than the CBCT images in terms of soft-tissue visualization, the US system can provide an optional image-guided radiation therapy (IGRT) system. US imaging might be a better IGRT system than CBCT, despite difficulty in capturing the entire uterus. Uterine shifts based on US imaging contains relative uterus-bone displacement, which is not taken into consideration using CBCT bone match.

  2. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization

  3. A new method for real-time co-registration of 3D coronary angiography and intravascular ultrasound or optical coherence tomography

    Carlier, Stéphane, E-mail: sgcarlier@hotmail.com [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Didday, Rich [INDEC Medical Systems Inc., Santa Clara, CA (United States); Slots, Tristan [Pie Medical Imaging BV, Maastricht (Netherlands); Kayaert, Peter; Sonck, Jeroen [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium); El-Mourad, Mike; Preumont, Nicolas [Department of Cardiology, Erasme University Hospital, Université Libre de Bruxelles (ULB), Brussels (Belgium); Schoors, Dany; Van Camp, Guy [Department of Cardiology, Universitair Ziekenhuis - UZ Brussel, Brussels (Belgium)

    2014-06-15

    We present a new clinically practical method for online co-registration of 3D quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS) or optical coherence tomography (OCT). The workflow is based on two modified commercially available software packages. Reconstruction steps are explained and compared to previously available methods. The feasibility for different clinical scenarios is illustrated. The co-registration appears accurate, robust and induced a minimal delay on the normal cath lab activities. This new method is based on the 3D angiographic reconstruction of the catheter path and does not require operator’s identification of landmarks to establish the image synchronization.

  4. 3D rod-like copper oxide with nanowire hierarchical structure: Ultrasound assisted synthesis from Cu2(OH)3NO3 precursor, optical properties and formation mechanism

    Ba, Ningning; Zhu, Lianjie; Li, Hongbin; Zhang, Guangzhi; Li, Jianfa; Sun, Jingfeng

    2016-03-01

    3-dimensional (3D) rod-like CuO with nanowire hierarchical structure has been synthesized successfully by a facile ultrasound assisted method combined with thermal conversion, using rouaite Cu2(OH)3NO3 as the precursor. The product was characterized by XRD, SEM, TEM, HRTEM and FT-IR spectrum. Its optical properties were studied by means of UV-Vis diffuse reflectance absorption spectroscopy and photoluminescence (PL) spectrum. Series of control experiments have been performed to explore influencing factors to the product morphologies and a possible formation mechanism has been proposed. The results show that each CuO rod assembled by tens of nanowires is 200-300 nm in diameter and about 1000 nm in length. Each nanowire contains many interconnected nanoparticles with sizes of about 15 nm. Particularly, ultrasound processing was found beneficial to the formation of the 3D rod-like CuO with nanowire hierarchical structure.

  5. Modified biological training model for percutaneous renal surgery with ultrasound and fluoroscopy guidance

    QIU Zhi; YANG Yong; ZHANG Yi; SUN Yu-cheng

    2011-01-01

    Background The 12th rib is an important anatomic marker in the process of percutaneous renal surgery; while the previous models without ribs can not provide close simulation conditions to human upper abdomen. To facilitate the learning and training of percutaneous renal access and intrarenal procedures under ultrasound and fluoroscopy guidance, we reported a biological bench model for percutaneous renal surgery. Methods The model was developed using an ex vivo porcine kidney with a longer than 3 cm ureter, a flap of full thickness of thoracic wall with skin, subcutaneous fascia, muscle and two ribs, as well as the standard equipment for percutaneous nephrolithotomy. The porcine kidney with a catheterized ureter was placed within the porcine flap and fixed to a wooden board with two long steel nails. Afterward, contrast medium or physiological saline (0.9% sodium chloride solution) was injected through the ureter, and the urinary system was examined with a fluoroscopy unit or an ultrasound. Artificial stone material was implanted in the renal pelvis. After practicing, the model could be dissected for kidney examination and a technical analysis. Results The advantage of this model was simple to set up and inexpensive, by using widely available material. The biological bench model can be employed for percutanous renal access, tract dilation, nephroscopy, and stone disintegration in the training and learning of clinical practice. Imaging is feasible under fluoroscopic and ultrasound guidance. The kidney models were utilized in hands on courses with over 100 people, and 90.5% attendants rated the porcine kidney model for simulation of percutaneous renal surgery as 'very helpful" or "helpful". Conclusion This biological training model simulates realistically the clinical procedure of percutaneous nephrolithotomy under fluoroscopic and ultrasound guidance.

  6. Non-Invasive Targeted Peripheral Nerve Ablation Using 3D MR Neurography and MRI-Guided High-Intensity Focused Ultrasound (MR-HIFU: Pilot Study in a Swine Model.

    Merel Huisman

    Full Text Available Ultrasound (US-guided high intensity focused ultrasound (HIFU has been proposed for noninvasive treatment of neuropathic pain and has been investigated in in-vivo studies. However, ultrasound has important limitations regarding treatment guidance and temperature monitoring. Magnetic resonance (MR-imaging guidance may overcome these limitations and MR-guided HIFU (MR-HIFU has been used successfully for other clinical indications. The primary purpose of this study was to evaluate the feasibility of utilizing 3D MR neurography to identify and guide ablation of peripheral nerves using a clinical MR-HIFU system.Volumetric MR-HIFU was used to induce lesions in the peripheral nerves of the lower limbs in three pigs. Diffusion-prep MR neurography and T1-weighted images were utilized to identify the target, plan treatment and immediate post-treatment evaluation. For each treatment, one 8 or 12 mm diameter treatment cell was used (sonication duration 20 s and 36 s, power 160-300 W. Peripheral nerves were extracted < 3 hours after treatment. Ablation dimensions were calculated from thermal maps, post-contrast MRI and macroscopy. Histological analysis included standard H&E staining, Masson's trichrome and toluidine blue staining.All targeted peripheral nerves were identifiable on MR neurography and T1-weighted images and could be accurately ablated with a single exposure of focused ultrasound, with peak temperatures of 60.3 to 85.7°C. The lesion dimensions as measured on MR neurography were similar to the lesion dimensions as measured on CE-T1, thermal dose maps, and macroscopy. Histology indicated major hyperacute peripheral nerve damage, mostly confined to the location targeted for ablation.Our preliminary results indicate that targeted peripheral nerve ablation is feasible with MR-HIFU. Diffusion-prep 3D MR neurography has potential for guiding therapy procedures where either nerve targeting or avoidance is desired, and may also have potential for post

  7. Therapeutic ablation of the infrapatellar fat pad under ultrasound guidance: a pilot study

    Aim: To describe the technique of ablation of the infrapatellar fat pad using alcohol injection under ultrasound guidance and to assess the efficacy of the procedure in the relief of pain arising from fat pad impingement. Material and Methods: Consecutive patients with anterior knee pain and pathology in the infrapatellar fat pad, confirmed on magnetic resonance imaging (MRI), were enrolled in the study. A mixture of alcohol and local anaesthetic was injected under ultrasound guidance, with repeat injections at three-weekly intervals. Twelve patients (seven men, five women), mean age 30.8 years, underwent the procedure. Visual analogue scale pain scores were recorded before treatment and at the end of the treatment course. Results: Before treatment, the mean (±SD) pain score was 7.75 (±1.14). Patients underwent a mean of four injections (range 2-6). After treatment, the mean pain score was 2.92 (±2.61), representing a decrease of 62% (p < 0.001). Follow-up data were complete for all 12 patients. Other than short-lived pain at the time of injection, no serious side-effects were encountered. Conclusion: In patients with pain due to inflammation of the infrapatellar fat pad, ultrasound-guided alcohol ablation of the fat pad can provide effective symptom relief. The results of this pilot study indicate that a larger study is warranted to assess the long-term benefits of this well-tolerated procedure

  8. Application of DSA guidance combined with ultrasound localization in performing percutaneous transhepatic biliary drainage

    Objective: To investigate the application of DSA guidance combined with ultrasound localization in performing percutaneous transhepatic biliary drainage (PTBD). Methods: A total of 32 cases with malignant obstructive jaundice were enrolled in this study. The primary malignancy included primary liver cancer (n=4), bile duct carcinoma (n=21), gallbladder carcinoma with hepatic hilar metastases (n=2), metastatic carcinoma (n=3) and adenocarcinoma of the head of pancreas (n=2). Palliative biliary tract external and/or internal drainage were carried out under DSA guidance together with ultrasonic localization. After the treatment, all the routine biochemical items were reexamined. The results were analyzed. Results: Successful puncturing and drainage with single manipulation was achieved in all the 32 patients, and the success rate was 100%. External drainage was employed in 21 cases, while external together with internal drainage was adopted in 11 cases. After the operation, the jaundice was reduced, the liver function and clinical symptoms were relieved, and the patient's living quality was improved. Conclusion: With the help of DSA guidance combined with ultrasound localization the technical success rate of PTBD can be greatly improved and the operation time can be shortened. This technique is safe and effective, and it is very helpful in reducing patient's suffering. Meanwhile, the exposure dose of irradiation can be lessened to a large extent. (authors)

  9. Electrostimulation with or without ultrasound-guidance in interscalene brachial plexus block for shoulder surgery.

    Salem, Mohamed H; Winckelmann, Jörg; Geiger, Peter; Mehrkens, Hans-Hinrich; Salem, Khaled H

    2012-08-01

    In a prospective controlled trial to compare conventional interscalene brachial plexus block (ISBPB) using anatomic landmarks and electro-stimulation with a combined technique of ultrasound guidance followed by nerve stimulation, 60 patients were randomized into 2 matched equal groups: Group A using nerve stimulation (NS) alone and Group B using the combination of ultrasound and NS. The time to detect the plexus (3.9 ± 4 min in Group A and 3.3 ± 1.4 min in Group B) was not significantly different. We needed to reposition the needle once (n = 13) or twice (n = 4) in Group B. First-shot motor response was achieved in all but one patient in Group A; here we were only able to locate the plexus by use of ultrasound. None of the patients needed general anaesthesia. There were no significant differences between postoperative pain, motor power, or patient's satisfaction. ISBPB seems similarly effective using electro-stimulation and ultrasound if performed by experienced anesthesiologists. PMID:22391670

  10. 3D Ultrasound Data Acquisition and Its Development%三维超声数据采集技术及发展

    郭境峰; 蔡泽杭; 李德来

    2014-01-01

    近年来,超声三维成像技术得到了长足的发展并广泛应用于临床诊断领域。三维超声成像技术主要包括数据采集和重建后处理两部分,本文提出了三维数据采集技术的四个发展阶段:自由臂、辅助装置、机械容积探头、电子面阵探头。然后对各个阶段的各项采集技术分别进行描述,并归纳了其优缺点。%In recent years, 3D ultrasound imaging technology has achieved considerable development and is widely used in clinical diagnosis. 3D ultrasound imaging mainly includes data acquisition and reconstruction post-processing. This paper presents four development stages of 3D data acquisition: freehand, auxiliary device, mechanical volume probe, and electronic planar array probe. Each stage is described respectively, folowed by a summary of its advantages and disadvantages.

  11. Ultrasound-assisted fabrication of a new nano-rods 3D copper(II)-organic coordination supramolecular compound.

    Hanifehpour, Younes; Safarifard, Vahid; Morsali, Ali; Mirtamizdoust, Babak; Joo, Sang Woo

    2016-07-01

    High-energy ultrasound irradiation has been used for the synthesis of a new copper(II) coordination supramolecular compound, [Cu2(μ-O2CCH3)2(μ-OOCCH3)(phen)2](BF4) (1), ("phen" is 1,10-phenanthroline) with nano-rods morphology. The new nano-structure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), FT-IR spectroscopy and elemental analyses. Compound 1 was structurally characterized by single crystal X-ray diffraction. The utilization of high intensity ultrasound has found as a facile, environmentally friendly, and versatile synthetic tool for the supramolecular coordination compounds. PMID:26964941

  12. Integration of 3D Printed and Micropatterned Polycaprolactone Scaffolds for Guidance of Oriented Collagenous Tissue Formation In Vivo.

    Pilipchuk, Sophia P; Monje, Alberto; Jiao, Yizu; Hao, Jie; Kruger, Laura; Flanagan, Colleen L; Hollister, Scott J; Giannobile, William V

    2016-03-01

    Scaffold design incorporating multiscale cues for clinically relevant, aligned tissue regeneration has potential to improve structural and functional integrity of multitissue interfaces. The objective of this preclinical study is to develop poly(ε-caprolactone) (PCL) scaffolds with mesoscale and microscale architectural cues specific to human ligament progenitor cells and assess their ability to form aligned bone-ligament-cementum complexes in vivo. PCL scaffolds are designed to integrate a 3D printed bone region with a micropatterned PCL thin film consisting of grooved pillars. The patterned film region is seeded with human ligament cells, fibroblasts transduced with bone morphogenetic protein-7 genes seeded within the bone region, and a tooth dentin segment positioned on the ligament region prior to subcutaneous implantation into a murine model. Results indicate increased tissue alignment in vivo using micropatterned PCL films, compared to random-porous PCL. At week 6, 30 μm groove depth significantly enhances oriented collagen fiber thickness, overall cell alignment, and nuclear elongation relative to 10 μm groove depth. This study demonstrates for the first time that scaffolds with combined hierarchical mesoscale and microscale features can align cells in vivo for oral tissue repair with potential for improving the regenerative response of other bone-ligament complexes. PMID:26820240

  13. SU-E-J-45: The Correlation Between CBCT Flat Panel Misalignment and 3D Image Guidance Accuracy

    Kenton, O; Valdes, G; Yin, L; Teo, B [The Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Brousmiche, S; Wikler, D [Ion Beam Application, Louvain-la-neuve (Belgium)

    2015-06-15

    Purpose To simulate the impact of CBCT flat panel misalignment on the image quality, the calculated correction vectors in 3D image guided proton therapy and to determine if these calibration errors can be caught in our QA process. Methods The X-ray source and detector geometrical calibration (flexmap) file of the CBCT system in the AdaPTinsight software (IBA proton therapy) was edited to induce known changes in the rotational and translational calibrations of the imaging panel. Translations of up to ±10 mm in the x, y and z directions (see supplemental) and rotational errors of up to ±3° were induced. The calibration files were then used to reconstruct the CBCT image of a pancreatic patient and CatPhan phantom. Correction vectors were calculated for the patient using the software’s auto match system and compared to baseline values. The CatPhan CBCT images were used for quantitative evaluation of image quality for each type of induced error. Results Translations of 1 to 3 mm in the x and y calibration resulted in corresponding correction vector errors of equal magnitude. Similar 10mm shifts were seen in the y-direction; however, in the x-direction, the image quality was too degraded for a match. These translational errors can be identified through differences in isocenter from orthogonal kV images taken during routine QA. Errors in the z-direction had no effect on the correction vector and image quality.Rotations of the imaging panel calibration resulted in corresponding correction vector rotations of the patient images. These rotations also resulted in degraded image quality which can be identified through quantitative image quality metrics. Conclusion Misalignment of CBCT geometry can lead to incorrect translational and rotational patient correction vectors. These errors can be identified through QA of the imaging isocenter as compared to orthogonal images combined with monitoring of CBCT image quality.

  14. SU-E-J-45: The Correlation Between CBCT Flat Panel Misalignment and 3D Image Guidance Accuracy

    Purpose To simulate the impact of CBCT flat panel misalignment on the image quality, the calculated correction vectors in 3D image guided proton therapy and to determine if these calibration errors can be caught in our QA process. Methods The X-ray source and detector geometrical calibration (flexmap) file of the CBCT system in the AdaPTinsight software (IBA proton therapy) was edited to induce known changes in the rotational and translational calibrations of the imaging panel. Translations of up to ±10 mm in the x, y and z directions (see supplemental) and rotational errors of up to ±3° were induced. The calibration files were then used to reconstruct the CBCT image of a pancreatic patient and CatPhan phantom. Correction vectors were calculated for the patient using the software’s auto match system and compared to baseline values. The CatPhan CBCT images were used for quantitative evaluation of image quality for each type of induced error. Results Translations of 1 to 3 mm in the x and y calibration resulted in corresponding correction vector errors of equal magnitude. Similar 10mm shifts were seen in the y-direction; however, in the x-direction, the image quality was too degraded for a match. These translational errors can be identified through differences in isocenter from orthogonal kV images taken during routine QA. Errors in the z-direction had no effect on the correction vector and image quality.Rotations of the imaging panel calibration resulted in corresponding correction vector rotations of the patient images. These rotations also resulted in degraded image quality which can be identified through quantitative image quality metrics. Conclusion Misalignment of CBCT geometry can lead to incorrect translational and rotational patient correction vectors. These errors can be identified through QA of the imaging isocenter as compared to orthogonal images combined with monitoring of CBCT image quality

  15. Automatic registration between 3D intra-operative ultrasound and pre-operative CT images of the liver based on robust edge matching

    The registration of a three-dimensional (3D) ultrasound (US) image with a computed tomography (CT) or magnetic resonance image is beneficial in various clinical applications such as diagnosis and image-guided intervention of the liver. However, conventional methods usually require a time-consuming and inconvenient manual process for pre-alignment, and the success of this process strongly depends on the proper selection of initial transformation parameters. In this paper, we present an automatic feature-based affine registration procedure of 3D intra-operative US and pre-operative CT images of the liver. In the registration procedure, we first segment vessel lumens and the liver surface from a 3D B-mode US image. We then automatically estimate an initial registration transformation by using the proposed edge matching algorithm. The algorithm finds the most likely correspondences between the vessel centerlines of both images in a non-iterative manner based on a modified Viterbi algorithm. Finally, the registration is iteratively refined on the basis of the global affine transformation by jointly using the vessel and liver surface information. The proposed registration algorithm is validated on synthesized datasets and 20 clinical datasets, through both qualitative and quantitative evaluations. Experimental results show that automatic registration can be successfully achieved between 3D B-mode US and CT images even with a large initial misalignment.

  16. 3D versus 2D Systematic Transrectal Ultrasound-Guided Prostate Biopsy: Higher Cancer Detection Rate in Clinical Practice

    Alexandre Peltier

    2013-01-01

    Full Text Available Objectives. To compare prostate cancer detection rates of extended 2D versus 3D biopsies and to further assess the clinical impact of this method in day-to-day practice. Methods. We analyzed the data of a cohort of 220 consecutive patients with no prior history of prostate cancer who underwent an initial prostate biopsy in daily practice due to an abnormal PSA and/or DRE using, respectively, the classical 2D and the new 3D systems. All the biopsies were done by a single experienced operator using the same standardized protocol. Results. There was no significant difference in terms of age, total PSA, or prostate volume between the two groups. However, cancer detection rate was significantly higher using the 3D versus the 2D system, 50% versus 34% (P<0.05. There was no statistically significant difference while comparing the 2 groups in term of nonsignificant cancer detection. Conclusion. There is reasonable evidence demonstrating the superiority of the 3D-guided biopsies in detecting prostate cancers that would have been missed using the 2D extended protocol.

  17. Evaluation of a prototype 3D ultrasound system for multimodality imaging of cervical nodes for adaptive radiation therapy

    Fraser, Danielle; Fava, Palma; Cury, Fabio; Vuong, Te; Falco, Tony; Verhaegen, Frank

    2007-03-01

    Sonography has good topographic accuracy for superficial lymph node assessment in patients with head and neck cancers. It is therefore an ideal non-invasive tool for precise inter-fraction volumetric analysis of enlarged cervical nodes. In addition, when registered with computed tomography (CT) images, ultrasound information may improve target volume delineation and facilitate image-guided adaptive radiation therapy. A feasibility study was developed to evaluate the use of a prototype ultrasound system capable of three dimensional visualization and multi-modality image fusion for cervical node geometry. A ceiling-mounted optical tracking camera recorded the position and orientation of a transducer in order to synchronize the transducer's position with respect to the room's coordinate system. Tracking systems were installed in both the CT-simulator and radiation therapy treatment rooms. Serial images were collected at the time of treatment planning and at subsequent treatment fractions. Volume reconstruction was performed by generating surfaces around contours. The quality of the spatial reconstruction and semi-automatic segmentation was highly dependent on the system's ability to track the transducer throughout each scan procedure. The ultrasound information provided enhanced soft tissue contrast and facilitated node delineation. Manual segmentation was the preferred method to contour structures due to their sonographic topography.

  18. Localization of the cricothyroid muscle under ultrasound guidance for vagal nerve mapping.

    Yang, Tsui-Fen; Wang, Jia-Chi; Hsu, Sanford P C; Lee, Cheng-Chia; Lin, Chun-Fu; Chiu, Jan-Wei; Lai, Chih-Jou; Chan, Rai-Chi; Lee, Shinn-Shing

    2015-05-01

    During surgical removal of tumors of the skull base or cerebellopontine angle with brainstem compression, the vagus nerve is at a high risk for injury that can result in permanent or transient swallowing and speech dysfunction. Intramuscular recording of cricothyroid muscle can be used for vagal nerve mapping during intraoperative neurophysiologic monitoring so as to prevent the above complications. However, it is a small muscle that lies beneath the strap muscles over the anterior neck and is not easily accessible by a blind approach. Here, we present a case in which cricothyroid muscle was identified for precise electrode placement under ultrasound guidance during preparation for intraoperative monitoring. We concluded that localization of the cricothyroid muscle by ultrasonography proved to be a feasible and easy technique, and the compound muscle action potential recorded by this approach is clearly recognizable during intraoperative vagal nerve mapping. PMID:25681020

  19. Intensity-Based Registration of Freehand 3D Ultrasound and CT-scan Images of the Kidney

    LEROY, Antoine; Mozer, Pierre; Payan, Yohan; Troccaz, Jocelyne

    2007-01-01

    This paper presents a method to register a pre-operative Computed-Tomography (CT) volume to a sparse set of intra-operative Ultra-Sound (US) slices. In the context of percutaneous renal puncture, the aim is to transfer planning information to an intra-operative coordinate system. The spatial position of the US slices is measured by optically localizing a calibrated probe. Assuming the reproducibility of kidney motion during breathing, and no deformation of the organ, the method consists in op...

  20. An image-guidance system for dynamic dose calculation in prostate brachytherapy using ultrasound and fluoroscopy

    Purpose: Brachytherapy is a standard option of care for prostate cancer patients but may be improved by dynamic dose calculation based on localized seed positions. The American Brachytherapy Society states that the major current limitation of intraoperative treatment planning is the inability to localize the seeds in relation to the prostate. An image-guidance system was therefore developed to localize seeds for dynamic dose calculation. Methods: The proposed system is based on transrectal ultrasound (TRUS) and mobile C-arm fluoroscopy, while using a simple fiducial with seed-like markers to compute pose from the nonencoded C-arm. Three or more fluoroscopic images and an ultrasound volume are acquired and processed by a pipeline of algorithms: (1) seed segmentation, (2) fiducial detection with pose estimation, (3) seed matching with reconstruction, and (4) fluoroscopy-to-TRUS registration. Results: The system was evaluated on ten phantom cases, resulting in an overall mean error of 1.3 mm. The system was also tested on 37 patients and each algorithm was evaluated. Seed segmentation resulted in a 1% false negative rate and 2% false positive rate. Fiducial detection with pose estimation resulted in a 98% detection rate. Seed matching with reconstruction had a mean error of 0.4 mm. Fluoroscopy-to-TRUS registration had a mean error of 1.3 mm. Moreover, a comparison of dose calculations between the authors’ intraoperative method and an independent postoperative method shows a small difference of 7% and 2% forD90 and V100, respectively. Finally, the system demonstrated the ability to detect cold spots and required a total processing time of approximately 1 min. Conclusions: The proposed image-guidance system is the first practical approach to dynamic dose calculation, outperforming earlier solutions in terms of robustness, ease of use, and functional completeness

  1. Pulsed radiofrequency on radial nerve under ultrasound guidance for treatment of intractable lateral epicondylitis.

    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. PMID:26896944

  2. Improvement in toxicity in high risk prostate cancer patients treated with image-guided intensity-modulated radiotherapy compared to 3D conformal radiotherapy without daily image guidance

    Image-guided radiotherapy (IGRT) facilitates the delivery of a very precise radiation dose. In this study we compare the toxicity and biochemical progression-free survival between patients treated with daily image-guided intensity-modulated radiotherapy (IG-IMRT) and 3D conformal radiotherapy (3DCRT) without daily image guidance for high risk prostate cancer (PCa). A total of 503 high risk PCa patients treated with radiotherapy (RT) and endocrine treatment between 2000 and 2010 were retrospectively reviewed. 115 patients were treated with 3DCRT, and 388 patients were treated with IG-IMRT. 3DCRT patients were treated to 76 Gy and without daily image guidance and with 1–2 cm PTV margins. IG-IMRT patients were treated to 78 Gy based on daily image guidance of fiducial markers, and the PTV margins were 5–7 mm. Furthermore, the dose-volume constraints to both the rectum and bladder were changed with the introduction of IG-IMRT. The 2-year actuarial likelihood of developing grade > = 2 GI toxicity following RT was 57.3% in 3DCRT patients and 5.8% in IG-IMRT patients (p < 0.001). For GU toxicity the numbers were 41.8% and 29.7%, respectively (p = 0.011). On multivariate analysis, 3DCRT was associated with a significantly increased risk of developing grade > = 2 GI toxicity compared to IG-IMRT (p < 0.001, HR = 11.59 [CI: 6.67-20.14]). 3DCRT was also associated with an increased risk of developing GU toxicity compared to IG-IMRT. The 3-year actuarial biochemical progression-free survival probability was 86.0% for 3DCRT and 90.3% for IG-IMRT (p = 0.386). On multivariate analysis there was no difference in biochemical progression-free survival between 3DCRT and IG-IMRT. The difference in toxicity can be attributed to the combination of the IMRT technique with reduced dose to organs-at-risk, daily image guidance and margin reduction

  3. Ultrasound -- Pelvis

    Full Text Available ... investigation of the uterine cavity . Three-dimensional (3-D) ultrasound permits evaluation of the uterus and ovaries ... abnormal uterine bleeding Some physicians also use 3-D ultrasound or sonohysterography for patients with infertility. Three- ...

  4. Intensity-Based Registration of Freehand 3D Ultrasound and CT-scan Images of the Kidney

    Leroy, Antoine; Payan, Yohan; Troccaz, Jocelyne

    2007-01-01

    This paper presents a method to register a pre-operative Computed-Tomography (CT) volume to a sparse set of intra-operative Ultra-Sound (US) slices. In the context of percutaneous renal puncture, the aim is to transfer planning information to an intra-operative coordinate system. The spatial position of the US slices is measured by optically localizing a calibrated probe. Assuming the reproducibility of kidney motion during breathing, and no deformation of the organ, the method consists in optimizing a rigid 6 Degree Of Freedom (DOF) transform by evaluating at each step the similarity between the set of US images and the CT volume. The correlation between CT and US images being naturally rather poor, the images have been preprocessed in order to increase their similarity. Among the similarity measures formerly studied in the context of medical image registration, Correlation Ratio (CR) turned out to be one of the most accurate and appropriate, particularly with the chosen non-derivative minimization scheme, n...

  5. Clinical feasibility of 3D automated coronary atherosclerotic plaque quantification algorithm on coronary computed tomography angiography: Comparison with intravascular ultrasound

    To evaluate the diagnostic performance of automated coronary atherosclerotic plaque quantification (QCT) by different users (expert/non-expert/automatic). One hundred fifty coronary artery segments from 142 patients who underwent coronary computed tomography angiography (CCTA) and intravascular ultrasound (IVUS) were analyzed. Minimal lumen area (MLA), maximal lumen area stenosis percentage (%AS), mean plaque burden percentage (%PB), and plaque volume were measured semi-automatically by expert, non-expert, and fully automatic QCT analyses, and then compared to IVUS. Between IVUS and expert QCT analysis, the correlation coefficients (r) for the MLA, %AS, %PB, and plaque volume were excellent: 0.89 (p < 0.001), 0.84 (p < 0.001), 0.91 (p < 0.001), and 0.94 (p < 0.001), respectively. There were no significant differences in the mean parameters (all p values >0.05) except %AS (p = 0.01). The automatic QCT analysis showed comparable performance to non-expert QCT analysis, showing correlation coefficients (r) of the MLA (0.80 vs. 0.82), %AS (0.82 vs. 0.80), %PB (0.84 vs. 0.73), and plaque volume (0.84 vs. 0.79) when they were compared to IVUS, respectively. Fully automatic QCT analysis showed clinical utility compared with IVUS, as well as a compelling performance when compared with semiautomatic analyses. (orig.)

  6. Clinical feasibility of 3D automated coronary atherosclerotic plaque quantification algorithm on coronary computed tomography angiography: Comparison with intravascular ultrasound

    Park, Hyung-Bok [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); Myongji Hospital, Division of Cardiology, Cardiovascular Center, Goyang (Korea, Republic of); Lee, Byoung Kwon [Yonsei University College of Medicine, Division of Cardiology, Gangnam Severance Hospital, Seoul (Korea, Republic of); Shin, Sanghoon [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); National Health Insurance Corporation Ilsan Hospital, Division of Cardiology, Goyang (Korea, Republic of); Heo, Ran; Chang, Hyuk-Jae; Chung, Namsik [Yonsei University Health System, Yonsei-Cedar Sinai Integrative Cardiovascular Imaging Research Center, Seoul (Korea, Republic of); Yonsei University Health System, Division of Cardiology, Severance Cardiovascular Hospital, Seoul (Korea, Republic of); Arsanjani, Reza [Cedars-Sinai Medical Center, Departments of Imaging and Medicine, Cedars-Sinai Heart Institute, Los Angeles, CA (United States); Kitslaar, Pieter H. [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Medis medical Imaging Systems B.V., Leiden (Netherlands); Broersen, Alexander; Dijkstra, Jouke [Leiden University Medical Center, Department of Radiology, Division of Image Processing, Leiden (Netherlands); Ahn, Sung Gyun [Yonsei University Wonju Severance Christian Hospital, Division of Cardiology, Wonju (Korea, Republic of); Min, James K. [New York-Presbyterian Hospital, Institute for Cardiovascular Imaging, Weill-Cornell Medical College, New York, NY (United States); Hong, Myeong-Ki; Jang, Yangsoo [Yonsei University Health System, Division of Cardiology, Severance Cardiovascular Hospital, Seoul (Korea, Republic of)

    2015-10-15

    To evaluate the diagnostic performance of automated coronary atherosclerotic plaque quantification (QCT) by different users (expert/non-expert/automatic). One hundred fifty coronary artery segments from 142 patients who underwent coronary computed tomography angiography (CCTA) and intravascular ultrasound (IVUS) were analyzed. Minimal lumen area (MLA), maximal lumen area stenosis percentage (%AS), mean plaque burden percentage (%PB), and plaque volume were measured semi-automatically by expert, non-expert, and fully automatic QCT analyses, and then compared to IVUS. Between IVUS and expert QCT analysis, the correlation coefficients (r) for the MLA, %AS, %PB, and plaque volume were excellent: 0.89 (p < 0.001), 0.84 (p < 0.001), 0.91 (p < 0.001), and 0.94 (p < 0.001), respectively. There were no significant differences in the mean parameters (all p values >0.05) except %AS (p = 0.01). The automatic QCT analysis showed comparable performance to non-expert QCT analysis, showing correlation coefficients (r) of the MLA (0.80 vs. 0.82), %AS (0.82 vs. 0.80), %PB (0.84 vs. 0.73), and plaque volume (0.84 vs. 0.79) when they were compared to IVUS, respectively. Fully automatic QCT analysis showed clinical utility compared with IVUS, as well as a compelling performance when compared with semiautomatic analyses. (orig.)

  7. Non-rigid registration of a 3D ultrasound and a MR image data set of the female pelvic floor using a biomechanical model

    Rexilius Jan

    2005-03-01

    Full Text Available Abstract Background The visual combination of different modalities is essential for many medical imaging applications in the field of Computer-Assisted medical Diagnosis (CAD to enhance the clinical information content. Clinically, incontinence is a diagnosis with high clinical prevalence and morbidity rate. The search for a method to identify risk patients and to control the success of operations is still a challenging task. The conjunction of magnetic resonance (MR and 3D ultrasound (US image data sets could lead to a new clinical visual representation of the morphology as we show with corresponding data sets of the female anal canal with this paper. Methods We present a feasibility study for a non-rigid registration technique based on a biomechanical model for MR and US image data sets of the female anal canal as a base for a new innovative clinical visual representation. Results It is shown in this case study that the internal and external sphincter region could be registered elastically and the registration partially corrects the compression induced by the ultrasound transducer, so the MR data set showing the native anatomy is used as a frame for the US data set showing the same region with higher resolution but distorted by the transducer Conclusion The morphology is of special interest in the assessment of anal incontinence and the non-rigid registration of normal clinical MR and US image data sets is a new field of the adaptation of this method incorporating the advantages of both technologies.

  8. Mitigation of Variability among 3D Echocardiography-Derived Regional Strain Values Acquired by Multiple Ultrasound Systems by Vendor Independent Analysis.

    Cole Streiff

    Full Text Available This study compared the variability of 3D echo derived circumferential and longitudinal strain values computed from vendor-specific and vendor-independent analyses of images acquired using ultrasound systems from different vendors.Ten freshly harvested porcine hearts were studied. Each heart was mounted on a custom designed phantom and driven to simulate normal cardiac motion. Cardiac rotation was digitally controlled and held constant at 5°, while pumped stroke volume (SV ranged from 30-70ml. Full-volume image data was acquired using three different ultrasound systems from different vendors. The image data was analyzed for longitudinal and circumferential strains (LS, CS using both vendor-specific and vendor-independent analysis packages.Good linear relationships were observed for each vendor-specific analysis package for both CS and LS at the mid-anterior segment, with correlation coefficients ranging from 0.82-0.91 (CS and 0.86-0.89 (LS. Comparable linear regressions were observed for results determined by a vendor independent program (CS: R = 0.82-0.89; LS: R = 0.86-0.89. Variability between analysis packages was examined via a series of ANOVA tests. A statistical difference was found between vendor-specific analysis packages (p0.05.Circumferential and longitudinal regional strain values differ when quantified by vendor-specific analysis packages; however, this variability is mitigated by use of a vendor-independent quantification method. These results suggest that echocardiograms acquired using different ultrasound systems could be meaningfully compared using vendor-independent software.

  9. Position tracking of moving liver lesion based on real-time registration between 2D ultrasound and 3D preoperative images

    Weon, Chijun; Hyun Nam, Woo; Lee, Duhgoon; Ra, Jong Beom, E-mail: jbra@kaist.ac.kr [Department of Electrical Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Lee, Jae Young [Department of Radiology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of)

    2015-01-15

    Purpose: Registration between 2D ultrasound (US) and 3D preoperative magnetic resonance (MR) (or computed tomography, CT) images has been studied recently for US-guided intervention. However, the existing techniques have some limits, either in the registration speed or the performance. The purpose of this work is to develop a real-time and fully automatic registration system between two intermodal images of the liver, and subsequently an indirect lesion positioning/tracking algorithm based on the registration result, for image-guided interventions. Methods: The proposed position tracking system consists of three stages. In the preoperative stage, the authors acquire several 3D preoperative MR (or CT) images at different respiratory phases. Based on the transformations obtained from nonrigid registration of the acquired 3D images, they then generate a 4D preoperative image along the respiratory phase. In the intraoperative preparatory stage, they properly attach a 3D US transducer to the patient’s body and fix its pose using a holding mechanism. They then acquire a couple of respiratory-controlled 3D US images. Via the rigid registration of these US images to the 3D preoperative images in the 4D image, the pose information of the fixed-pose 3D US transducer is determined with respect to the preoperative image coordinates. As feature(s) to use for the rigid registration, they may choose either internal liver vessels or the inferior vena cava. Since the latter is especially useful in patients with a diffuse liver disease, the authors newly propose using it. In the intraoperative real-time stage, they acquire 2D US images in real-time from the fixed-pose transducer. For each US image, they select candidates for its corresponding 2D preoperative slice from the 4D preoperative MR (or CT) image, based on the predetermined pose information of the transducer. The correct corresponding image is then found among those candidates via real-time 2D registration based on a

  10. The Relationship of 3D Translabial Ultrasound Anal Sphincter Complex Measurements to Postpartum Anal and Fecal Incontinence

    MERIWETHER, Kate V.; HALL, Rebecca J.; LEEMAN, Lawrence M.; MIGLIACCIO, Laura; QUALLS, Clifford; ROGERS, Rebecca G.

    2015-01-01

    Objective We aimed to determine whether ASC measurements on translabial ultrasound (TL-US) were related to anal incontinence (AI) or fecal incontinence (FI) symptoms six months postpartum. Methods A prospective cohort of primiparous women underwent TL-US six months after a vaginal birth (VB) or Cesarean delivery (CD). Muscle thickness was measured at 3, 6, 9, and 12 o’clock positions of the external sphincter (EAS), the same four quadrants of the internal sphincter (IAS) at proximal, mid, and distal levels, and at the bilateral pubovisceralis muscle (PVM). Measurements were correlated to AI and FI on the Wexner Fecal Incontinence Scale, with sub-analyses by mode of delivery. The odds ratio (OR) of symptoms was calculated for every one millimeter increase in muscle thickness (E1MIT). Results 423 women (299 VB, 124 CD) had TL-US six months postpartum. Decreased AI risk was associated with thicker measurements at the 6 o’clock (OR 0.74 E1MIT) and 9 o’clock proximal IAS (OR 0.71 E1MIT) in the entire cohort. For CD women, thicker measurements of the 9 o’clock proximal IAS were associated with decreased risk of AI (OR 0.56 E1MIT) and thicker distal 6 o’clock IAS measurements were related to a decreased risk of FI (OR 0.37 E1MIT). For VB women, no sphincter measurements were significantly related to symptoms, but thicker PVM measurements were associated with increased risk of AI (right side OR 1.32 E1MIT; left side OR 1.21 E1MIT). Conclusions ASC anatomy is associated with AI and FI in certain locations; these locations varybased on the patient’s mode of delivery. PMID:26085463

  11. Intravascular Ultrasound Guidance to Minimize the use of Iodine Contrast in Percutaneous Coronary Intervention: The MOZART Randomized Controlled Trial

    Mariani, José; Guedes, Cristiano; Soares, Paulo; Zalc, Silvio; Campos, Carlos M.; Augusto C Lopes; Spadaro, André G.; Perin, Marco A.; Filho, Antonio Esteves; Takimura, Celso K.; Ribeiro, Expedito; Kalil-Filho, Roberto; Edelman, Elazer R.; Serruys, Patrick W.; Pedro A. Lemos

    2014-01-01

    Objectives: The aim of this study was to evaluate the impact of intravascular ultrasound (IVUS) guidance on the final volume of contrast agent used in patients undergoing percutaneous coronary intervention (PCI). Background: To date, few approaches have been described to reduce the final dose of contrast agent in PCIs. We hypothesized that IVUS might serve as an alternative imaging tool to angiography in many steps during PCI, thereby reducing the use of iodine contrast. Methods: ...

  12. Review of dynamic contrast-enhanced ultrasound guidance in ablation therapy for hepatocellular carcinoma

    Yasunori Minami; Masatoshi Kudo

    2011-01-01

    Local ablative techniques-percutaneous ethanol injection, microwave coagulation therapy and radiofrequency ablation (RFA)-have been developed to treat unresectable hepatocellular carcinoma (HCC). The success rate of percutaneous ablation therapy for HCC depends on correct targeting of the tumor via an imaging technique. However, probe insertion often is not completely accurate for small HCC nodules, which are poorly defined on conventional B-mode ultrasound (US) alone. Thus, multiple sessions of ablation therapy are frequently required in difficult cases. By means of two breakthroughs in US technology, harmonic imaging and the development of second-generation contrast agents, dynamic contrast-enhanced harmonic US imaging with an intravenous contrast agent can depict tumor vascularity sensitively and accurately, and is able to evaluate small hypervascular HCCs even when B-mode US cannot adequately characterize the tumors. Therefore, dynamic contrast-enhanced US can facilitate RFA electrode placement in hypervascular HCC, which is poorly depicted by B-mode US. The use of dynamic contrast-enhanced US guidance in ablation therapy for liver cancer is an efficient approach. Here, we present an overview of the current status of dynamic contrast-enhanced US-guided ablation therapy, and summarize the current indications and outcomes of reported clinical use in comparison with that of other modalities.

  13. Automatic guidance of robotized 2D ultrasound probes with visual servoing based on image moments.

    Mebarki, Rafik

    2010-01-01

    There is error in the front page of the first document (v1). This dissertation presents a new 2D ultrasound-based visual servoing method. The main goal is to automatically guide a robotized 2D ultrasound probe held by a medical robot in order to reach a desired cross-section ultrasound image of an object of interest. This method allows to control both the in-plane and out-of-plane motions of a 2D ultrasound probe. It makes direct use of the 2D ultrasound image in the visual servo scheme, w...

  14. Feasibility of Using Volumetric Contrast-Enhanced Ultrasound with a 3-D Transducer to Evaluate Therapeutic Response after Targeted Therapy in Rabbit Hepatic VX2 Carcinoma.

    Kim, Jeehyun; Kim, Jung Hoon; Yoon, Soon Ho; Choi, Won Seok; Kim, Young Jae; Han, Joon Koo; Choi, Byung-Ihn

    2015-12-01

    The aim of this study was to assess the feasibility of using dynamic contrast-enhanced ultrasound (DCE-US) with a 3-D transducer to evaluate therapeutic responses to targeted therapy. Rabbits with hepatic VX2 carcinomas, divided into a treatment group (n = 22, 30 mg/kg/d sorafenib) and a control group (n = 13), were evaluated with DCE-US using 2-D and 3-D transducers and computed tomography (CT) perfusion imaging at baseline and 1 d after the first treatment. Perfusion parameters were collected, and correlations between parameters were analyzed. In the treatment group, both volumetric and 2-D DCE-US perfusion parameters, including peak intensity (33.2 ± 19.9 vs. 16.6 ± 10.7, 63.7 ± 20.0 vs. 30.1 ± 19.8), slope (15.3 ± 12.4 vs. 5.7 ± 4.5, 37.3 ± 20.4 vs. 15.7 ± 13.0) and area under the curve (AUC; 1004.1 ± 560.3 vs. 611.4 ± 421.1, 1332.2 ± 708.3 vs. 670.4 ± 388.3), had significantly decreased 1 d after the first treatment (p = 0.00). In the control group, 2-D DCE-US revealed that peak intensity, time to peak and slope had significantly changed (p AUC, AUC during wash-in and AUC during wash-out had significantly changed (p = 0.00). CT perfusion imaging parameters, including blood flow, blood volume and permeability of the capillary vessel surface, had significantly decreased in the treatment group (p = 0.00); however, in the control group, peak intensity and blood volume had significantly increased (p = 0.00). It is feasible to use DCE-US with a 3-D transducer to predict early therapeutic response after targeted therapy because perfusion parameters, including peak intensity, slope and AUC, significantly decreased, which is similar to the trend observed for 2-D DCE-US and CT perfusion imaging parameters. PMID:26365926

  15. Enhancing Macrophage Drug Delivery Efficiency via Co-Localization of Cells and Drug-Loaded Microcarriers in 3D Resonant Ultrasound Field.

    Lee, Yu-Hsiang; Wu, Zhen-Yu

    2015-01-01

    In this study, a novel synthetic 3D molecular transfer system which involved the use of model drug calcein-AM-encapsulated poly(lactic-co-glycolic acid) microspheres (CAPMs) and resonant ultrasound field (RUF) with frequency of 1 MHz and output intensity of 0.5 W/cm2 for macrophage drug delivery was explored. We hypothesized that the efficiency of CAPMs-mediated drug delivery aided by RUF can be promoted by increasing the contact opportunities between cells and the micrometer-sized drug carriers due to effects of acoustic radiation forces generated by RUF. Through the fluoromicroscopic and flow cytometric analyses, our results showed that both DH82 macrophages and CAPMs can be quickly brought to acoustic pressure nodes within 20 sec under RUF exposure, and were consequently aggregated throughout the time course. The efficacy of cellular uptake of CAPMs was enhanced with increased RUF exposure time where a 3-fold augmentation (P CAPM delivery efficiency was mainly contributed by the co-localization of cells and CAPMs resulting from the application of the RUF, rather than from sonoporation. In summary, the developed molecular delivery approach provides a feasible means for macrophage drug delivery. PMID:26267789

  16. Monte Carlo investigation of the dosimetric effect of the Autoscan ultrasound probe for guidance in radiotherapy

    Martyn, Michael; O'Shea, Tuathan; Harris, Emma; Bamber, Jeffrey; Gilroy, Stephen; Foley, Mark J.

    2016-04-01

    The aim of this study was to quantify the dosimetric effect of the Autoscan™ ultrasound probe, which is a 3D transperineal probe used for real-time tissue tracking during the delivery of radiotherapy. CT images of an anthropomorphic phantom, with and without the probe placed in contact with its surface, were obtained (0.75 mm slice width, 140 kVp). CT datasets were used for relative dose calculation in Monte Carlo simulations of a 7-field plan delivered to the phantom. The Monte Carlo software packages BEAMnrc and DOSXYZnrc were used for this purpose. A number of simulations, which varied the distance of the radiation field edge from the probe face (0 mm to 5 mm), were performed. Perineal surface doses as a function of distance from the radiation field edge, with and without the probe in place, were compared. The presence of the probe was found to result in an increase in perineal surface dose, relative to the maximum dose. The maximum increase in surface dose was 18.15%, at a probe face to field edge distance of 0 mm. However increases in surface dose fall-off rapidly as this distance increases, agreeing within Monte Carlo simulation uncertainty at distances >= 5 mm. Using data from three patient volunteers, a typical probe face to field edge distance was calculated to be ≍20 mm. Our results therefore indicate that the presence of the probe is unlikely to adversely affect a typical patient treatment, since the dosimetric effect of the probe is minimal at these distances.

  17. Fast and Accurate Data Extraction for Near Real-Time Registration of 3-D Ultrasound and Computed Tomography in Orthopedic Surgery.

    Brounstein, Anna; Hacihaliloglu, Ilker; Guy, Pierre; Hodgson, Antony; Abugharbieh, Rafeef

    2015-12-01

    Automatic, accurate and real-time registration is an important step in providing effective guidance and successful anatomic restoration in ultrasound (US)-based computer assisted orthopedic surgery. We propose a method in which local phase-based bone surfaces, extracted from intra-operative US data, are registered to pre-operatively segmented computed tomography data. Extracted bone surfaces are downsampled and reinforced with high curvature features. A novel hierarchical simplification algorithm is used to further optimize the point clouds. The final point clouds are represented as Gaussian mixture models and iteratively matched by minimizing the dissimilarity between them using an L2 metric. For 44 clinical data sets from 25 pelvic fracture patients and 49 phantom data sets, we report mean surface registration accuracies of 0.31 and 0.77 mm, respectively, with an average registration time of 1.41 s. Our results suggest the viability and potential of the chosen method for real-time intra-operative registration in orthopedic surgery. PMID:26365924

  18. General Ultrasound Imaging

    Full Text Available ... of the body. Advancements in ultrasound technology include three-dimensional (3-D) ultrasound that formats the sound wave data into 3-D images. A Doppler ultrasound study may be ...

  19. Ultrasound guided supraclavicular block.

    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.

  20. A 3-D Guidance Law for Air to Surface Missile%空对地导弹的变结构三维导引律

    陈胜琪

    2009-01-01

    Three dimension kinematic model for air to surface missile is given, then a variable structure guidance law is designed considering the characteristics of surface maneuver target. Performance of the guidance system is analyzed theoretically. Guidance law proposed in the paper can be implemented conveniently in engineering as it needs little target information. Numerical simulation result sustains the effectiveness of the guidance law.%推导了空对地导弹的三维导引律模型,并设计了针对机动目标的变结构导引律,分析了其制导特性.设计的导引律由于需要的目标信息少,可以便利地应用于实际工程中,数字仿真结果证实了设计的导引律的可行性.

  1. Animal study assessing safety of an acoustic coupling fluid that holds the potential to avoid surgically induced artifacts in 3D ultrasound guided operations

    Jakola, Asgeir S; Jørgensen, Arve; Selbekk, Tormod; Michler, Ralf-Peter; Solheim, Ole; Torp, Sverre H; Sagberg, Lisa M; Aadahl, Petter; Unsgård, Geirmund

    2014-01-01

    Background Use of ultrasound in brain tumor surgery is common. The difference in attenuation between brain and isotonic saline may cause artifacts that degrade the ultrasound images, potentially affecting resection grades and safety. Our research group has developed an acoustic coupling fluid that attenuates ultrasound energy like the normal brain. We aimed to test in animals if the newly developed acoustic coupling fluid may have harmful effects. Methods Eight rats were included for intrapar...

  2. Real-time needle guidance with photoacoustic and laser-generated ultrasound probes

    Colchester, Richard J.; Mosse, Charles A.; Nikitichev, Daniil I.; Zhang, Edward Z.; West, Simeon; Beard, Paul C.; Papakonstantinou, Ioannis; Desjardins, Adrien E.

    2015-03-01

    Detection of tissue structures such as nerves and blood vessels is of critical importance during many needle-based minimally invasive procedures. For instance, unintentional injections into arteries can lead to strokes or cardiotoxicity during interventional pain management procedures that involve injections in the vicinity of nerves. Reliable detection with current external imaging systems remains elusive. Optical generation and reception of ultrasound allow for depth-resolved sensing and they can be performed with optical fibers that are positioned within needles used in clinical practice. The needle probe developed in this study comprised separate optical fibers for generating and receiving ultrasound. Photoacoustic generation of ultrasound was performed on the distal end face of an optical fiber by coating it with an optically absorbing material. Ultrasound reception was performed using a high-finesse Fabry-Pérot cavity. The sensor data was displayed as an M-mode image with a real-time interface. Imaging was performed on a biological tissue phantom.

  3. Feasibility of Remote Real-Time Guidance of a Cardiac Examination Performed by Novices Using a Pocket-Sized Ultrasound Device

    Mai, Tuan V; Ahn, David T.; Phillips, Colin T.; Agan, Donna L.; Kimura, Bruce J

    2013-01-01

    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...

  4. Ultrasound guidance in regional anesthesia: state of the art review through challenging clinical scenarios

    Brian D Sites

    2009-01-01

    Full Text Available Brian D Sites1, John G Antonakakis21Departments of Anesthesiology and Orthopedic Surgery, Dartmouth Medical School, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; 2Department of Anesthesiology, University of Virginia Health System, Charlottesville, VA, USAAbstract: Ultrasound guided regional anesthesia (UGRA for peripheral nerve blockade is becoming increasingly popular. The advantage of ultrasound technology is that it affords the anesthesiologist the real time ability to visualize neural structures, needle advancement, and local anesthetic spread. Recent data suggest that UGRA generates improved success rates and reductions in performance times in comparison to traditional approaches. Further, the use of ultrasound technology in peripheral nerve blocks has provided insight into needle–nerve interactions, revealing distinct limitations of nerve stimulator techniques. Given that UGRA requires a unique set of skills, formal standards and guidelines are currently being developed by leadership societies in order to foster education and training. This review article, in a case vignette format, highlights important techniques, concepts, and limitations regarding the use of ultrasound to facilitate regional anesthesia. Clinically relevant aspects of ultrasound physics are also discussed.Keywords: ultrasound, regional anesthesia

  5. Ultrasound -- Pelvis

    Full Text Available ... kidneys. top of page What are some common uses of the procedure? In women, a pelvic ultrasound ... patients with abnormal uterine bleeding Some physicians also use 3-D ultrasound or sonohysterography for patients with ...

  6. Breakage of Needle during Intracavernosal Injection and Use of Portable Ultrasound Guidance for Removal

    Wayland Hsiao

    2013-01-01

    Full Text Available Purpose. Intracavernosal self-injection (ICI was first described in 1982, and remains a viable therapy for erectile dysfunction. However, intracorporal needle breakage can be a rare complication of therapy. We report a rare complication of intracorporal needle breakage and a retention of a 30-gauge needle in a 42-year-old paraplegic man. We discuss our experience in using portable high-frequency ultrasound intraoperatively to visualize and guide removal of a retained ICI needle. Materials and Methods. Review of case and ultrasound technique are presented. Results. Using intraoperative ultrasound imaging, the retained intracorporal needle was successfully removed from the patient's penis without any complications. Follow-up ultrasonography and X-ray confirmed complete removal of the needle. Conclusions. We report on the successful implementation and use of a portable high-frequency ultrasound probe to visualize a retained intracorporal needle inside the penis and its use to guide removal. Given the rapid proliferation of portable ultrasound machines in the operating room and out in the field, we expect these imaging techniques to become routine, especially in urological emergencies.

  7. Ultrasound and Electromyography Guidance for Injection of the Longus Colli With Botulinum Toxin for the Treatment of Cervical Dystonia.

    Allison, Stephen K; Odderson, Ib R

    2016-09-01

    Cervical dystonia, also called spasmodic torticollis, is a painful condition in which neck muscles contract involuntarily, and may cause abnormal head position or movements. The primary (or first line of) treatment of cervical dystonia is chemodenervation with injection of botulinum toxin into the affected muscles. We report a case of a young man with idiopathic cervical dystonia who developed anterocollis (forward flexion of the neck) not responsive to prior scalene and sternocleidomastoid muscle injections. To safely access the deeper cervical musculature, ultrasound (US) was used in conjunction with electromyography, to inject the longus colli muscles bilaterally. The patient responded well and had no complications. The longus colli has been reported to be injected using electromyography, fluoroscopy, computed tomography, and, less frequently, US. We propose that US guidance is an excellent technique for botulinum toxin injection, especially for deep cervical muscles such as the longus colli. PMID:26886108

  8. Ultrasound and PET-CT image fusion for prostate brachytherapy image guidance

    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 cm3, 8.86 cm3 and 20.11 cm3 for known standard volumes of 4 cm3, 9 cm3 and 20 cm3 respectively. Depth of penetration assessment of the ultrasound system produced an estimate of 5.37 ± 0.02 cm, indicating the

  9. Technical note: Reduction of radiation dose using ultrasound guidance during transjugular intrahepatic portosystemic shunt procedure

    The transjugular intrahepatic portosystemic shunt (TIPS) procedure for decompression of the portal venous system generally performed under fluoroscopic guidance has undergone continuous technical modifications recently. Due to the length of the procedure, the fluoroscopy times are reasonably high, thus increasing the risk from ionizing radiation. Radiation doses were measured for 19 patients using dose area product (DAP) meter. The average DAP value for the TIPS procedure was 63.86 Gy cm2 (21.12-117.07). Radiation doses to patients can be reduced with the use of USG guidance and intermittent fluoroscopy screening

  10. Technical note: Reduction of radiation dose using ultrasound guidance during transjugular intrahepatic portosystemic shunt procedure

    Roshan S Livingstone

    2011-01-01

    Full Text Available The transjugular intrahepatic portosystemic shunt (TIPS procedure for decompression of the portal venous system generally performed under fluoroscopic guidance has undergone continuous technical modifications recently. Due to the length of the procedure, the fluoroscopy times are reasonably high, thus increasing the risk from ionizing radiation. Radiation doses were measured for 19 patients using dose area product (DAP meter. The average DAP value for the TIPS procedure was 63.86 Gy cm 2 (21.12-117.07. Radiation doses to patients can be reduced with the use of USG guidance and intermittent fluoroscopy screening.

  11. A new technique for performing Syed-Neblett template interstitial implants for gynecologic malignancies using transrectal-ultrasound guidance

    Purpose: Interstitial brachytherapy plays an important role in the treatment of advanced and recurrent gynecologic malignancies. Unfortunately, the inability to visualize the tumor and surrounding normal structures during the implant has hampered the accuracy and safety of the implant. Transrectal ultrasound guided Syed-Neblett template implantation is a new technique for performing interstitial implants under direct visualization. The details of the technique are presented to demonstrate the ability to accurately guide needle placement into tumor and avoid needle insertion into critical surrounding normal structures. Methods and Materials: The transrectal ultrasound is positioned so that it can visualize the tumor, and normal surrounding structures in both transverse and longitudinal planes. The Syed-Neblett template is positioned and sutured into the perineum. Needles are inserted into the target area under direct visualization through transverse imaging. The bladder and rectum can be directly imaged and thus avoided. Longitudinal imaging is then used to guide the needles to the appropriate depth. In addition, it can be used to assess the length of the target volume and aid in determining the active length of the sources. Results: A total of 12 procedures have been performed on seven patients from August 30, 1995 to April 12, 1996. The presenting diseases included: Stage IIIb cervical cancer in four cases, recurrent endometrial cancer in two cases, and Stage III vaginal cancer in one case. The total length of time for implantation of the needles ranged from 45 to 165 min (median--130 min). Conclusion: Transrectal ultrasound guidance provides real-time visualization of the target volume and normal tissues during interstitial implantation of gynecologic malignancies and allows for accurate needle placement

  12. Fast Conformal Thermal Ablation in the Prostate with Transurethral Multi-Sectored Ultrasound Devices and MR Guidance

    Kinsey, Adam M.; Diederich, Chris J.; Nau, William H.; Ross, Anthony B.; Pauly, Kim Butts; Rieke, Viola; Sommer, Graham

    2007-05-01

    Transurethral ultrasound applicators incorporating an array of multisectored tubular transducers were evaluated in theoretical simulations and in vivo canine prostates under MR guidance as a method for fast, conformal thermal therapy of the prostate. Comprehensive simulations with a biothermal model investigated the effect on lesion creation of sector size, perfusion, treatment time, rectal cooling, prostate target dimensions, and feedback controller parameters (maximum temperature, pilot points at boundary, update times). In vivo canine prostates (n = 4) were treated with trisectored ultrasound transducers (3 mm OD) under MR temperature monitoring to contour the ablation zone (>52 C for 1-2 min) to the boundary of the prostate. Contiguous thermal lesions extended 2 cm in radius from the urethra in less than 15 min and independent sector control simultaneously allowed for conformal treatment in the angular dimension. Experiments investigated sequential translation of the transducer assembly within the catheter for tailoring heat treatments to different partitions in the prostate (base, apex) without changing the initial setup. This treatment method offered greater lesion shape control in three dimensions and slightly lengthened the overall treatment time. The MR temperature images correlated with post-treatment histology and accurately controlled the heating to the target boundary. MR-based control of transurethral ultrasound devices appeared more practical with multisectored transducers compared to rotating curvilinear and planar applicators due to less stringent requirements on spatial and temporal MR parameters. This study demonstrated the applicability of these devices in the prostate for anterior-lateral BPH treatment, and whole gland or quadrant target volumes for cancer treatment.

  13. Automatic guidance of an ultrasound probe by visual servoing based on B-mode image moments.

    Mebarki, Rafik; Krupa, Alexandre; Collewet, Christophe

    2008-01-01

    We propose a new visual servo approach to automatically control in real-time the full motion of a 2D ultrasound (US) probe held by a medical robot in order to reach a desired image of motionless soft tissue object in B-mode ultrasound imaging. Combinations of image moments of the observed object cross-section are used as feedback information in the visual control scheme. These visual features are extracted in real-time from the US image thanks to a fast image segmentation method. Simulations performed with a static US volume containing an egg-shaped object, and ex-vivo experiments using a robotized US probe that interacts with a motionless rabbit heart immersed in water, show the validity of this new approach and its robustness to different perturbations. This method shows promise for a variety of US-guided medical interventions that require real-time servoing. PMID:18982623

  14. Percutaneous transhepatic biliary drainage under fluoroscopic and ultrasound guidance for the treatment of obstructive jaundice: its clinical application

    Objective: To investigate the technical and clinical value of percutaneous transhepatic biliary drainage (PTBD) in treating patients of obstructive jaundice with the help of fluoroscopic and real-time ultrasound monitoring. Methods: A total of 78 patients with obstructive jaundice were enrolled in this study. The primary lesions included malignant diseases (n=70) and benign diseases (n=8). PTBD was carried out in all patients. Under fluoroscopic and real-time ultrasonography guidance, the biliary duct of the right hepatic lobe (n=52) or the biliary duct of the left hepatic lobe was punctured and the cholangiography was routinely performed. The drainage procedure was carried out. Results: PTBD was successfully accomplished in all patients. No severe complications, such as massive bleeding or biliary peritonitis, occurred. After the treatment the symptoms and signs of obstructive jaundice were gradually improved. The serum levels of both bilirubin and transaminase determined 1-2 weeks after the treatment were decreased, and the reductions were statistically significant when compared with the preoperative data (P<0.01). Conclusion: For the obstructive jaundice, PTBD under the guidance of fluoroscopy and real-time ultrasonography is an effective, safe, simple and economical treatment with fewer complications. (authors)

  15. Animal study assessing safety of an acoustic coupling fluid that holds the potential to avoid surgically induced artifacts in 3D ultrasound guided operations

    Use of ultrasound in brain tumor surgery is common. The difference in attenuation between brain and isotonic saline may cause artifacts that degrade the ultrasound images, potentially affecting resection grades and safety. Our research group has developed an acoustic coupling fluid that attenuates ultrasound energy like the normal brain. We aimed to test in animals if the newly developed acoustic coupling fluid may have harmful effects. Eight rats were included for intraparenchymal injection into the brain, and if no adverse reactions were detected, 6 pigs were to be included with injection of the coupling fluid into the subarachnoid space. Animal behavior, EEG registrations, histopathology and immunohistochemistry were used in assessment. In total, 14 animals were included, 8 rats and 6 pigs. We did not detect any clinical adverse effects, seizure activity on EEG or histopathological signs of tissue damage. The novel acoustic coupling fluid intended for brain tumor surgery appears safe in rats and pigs under the tested circumstances

  16. 3D Rapid Prototyping for Otolaryngology-Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling.

    Harley H L Chan

    Full Text Available The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i a mono-material paranasal sinus phantom for endoscopy training ii a multi-material skull base simulator and iii 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and

  17. Catheter-based endomyocardial delivery of mesenchymal precursor cells using 3D echo guidance improves cardiac function in a chronic myocardial injury ovine model.

    Cheng, Yanping; Yi, Genghua; Conditt, Gerard B; Sheehy, Alexander; Kolodgie, Frank D; Tellez, Armando; Polyakov, Igor; Gu, Anguo; Aboodi, Michael S; Wallace-Bradley, David; Schuster, Michael; Martens, Timothy; Itescu, Silviu; Kaluza, Greg L; Basu, Shubhayu; Virmani, Renu; Granada, Juan F; Sherman, Warren

    2013-01-01

    The administration of bone marrow-derived stem cells may provide a new treatment option for patients with heart failure. Transcatheter cell injection may require multi-imaging modalities to optimize delivery. This study sought to evaluate whether endomyocardial injection of mesenchymal precursor cells (MPCs) could be guided by real-time 3D echocardiography (RT3DE) in treating chronic, postinfarction (MI) left ventricular (LV) dysfunction in sheep. Four weeks after induction of an anterior wall myocardial infarction in 39 sheep, allogeneic MPCs in doses of either 25 × 10(6) (n = 10), 75 × 10(6) (n = 9), or 225 × 10(6) (n = 10) cells or nonconditioned control media (n = 10) were administered intramyocardially into infarct and border zone areas using a catheter designed for combined fluoroscopic and RT3DE-guided injections. LV function was assessed before and after injection. Infarct dimension and vascular density were evaluated histologically. RT3DE-guided injection procedures were safe. Compared to controls, the highest dose MPC treatment led to increments in ejection fraction (3 ventricula 3% in 225M MPCs vs. -5 ± 4% in the control group, p logistical obstacles. Significant increases in LV performance (ejection fraction and wall thickening) and neovascularization resulted from this technique, and so this technique has important implications for treating patients with postischemic LV dysfunction. PMID:23107489

  18. General Ultrasound Imaging

    Full Text Available ... data into 3-D images. A Doppler ultrasound study may be part of an ultrasound examination. Doppler ... not stain or discolor clothing. In some ultrasound studies, the transducer is attached to a probe and ...

  19. SU-D-BRF-07: Ultrasound and Fluoroscopy Based Intraoperative Image-Guidance System for Dynamic Dosimetry in Prostate Brachytherapy

    Kuo, N; Le, Y; Deguet, A; Prince, J; Song, D; Lee, J [Johns Hopkins University, Baltimore, MD (United States); Dehghan, E [Philips Research North America, Briarcliff Manor, NY (United States); Burdette, E [Acoustic MedSystems Inc., Savoy, IL (United States); Fichtinger, G [Queen' s University, Kingston, ON (Canada)

    2014-06-01

    Purpose: Prostate brachytherapy is a common treatment method for low-risk prostate cancer patients. Intraoperative treatment planning is known to improve the treatment procedure and the outcome. The current limitation of intraoperative treatment planning is the inability to localize the seeds in relation to the prostate. We developed an image-guidance system to fulfill this need to achieve intraoperative dynamic dosimetry in prostate brachytherapy. Methods: Our system is based on standard imaging equipments available in the operating room, including the transrectal ultrasound (TRUS) and the mobile C-arm. A simple fiducial is added to compute the C-arm pose. Three fluoroscopic images and an ultrasound volume of the seeds and the prostate are acquired and processed by four image processing algorithms: seed segmentation, fiducial detection with pose estimation, seed reconstruction, and seeds-to-TRUS registration. The updated seed positions allow the physician to assess the quality of implantation and dynamically adjust the treatment plan during the course of surgery to achieve improved exit dosimetry. Results: The system was tested on 10 phantoms and 37 patients. Seed segmentation resulted in a 1% false negative and 2% false positive rates. Fiducial detection with pose estimation resulted in a detection rate of 98%. Seed reconstruction had a mean reconstruction error of 0.4 mm. Seeds-to-TRUS registration had a mean registration error of 1.3 mm. The total processing time from image acquisition to registration was approximately 1 minute. Conclusion: We present an image-guidance system for intraoperative dynamic dosimetry in prostate brachytherapy. Using standard imaging equipments and a simple fiducial, our system can be easily adopted in any clinics. Robust image processing algorithms enable accurate and fast computation of the delivered dose. Especially, the system enables detection of possible hot/cold spots during the surgery, allowing the physician to address these

  20. SU-D-BRF-07: Ultrasound and Fluoroscopy Based Intraoperative Image-Guidance System for Dynamic Dosimetry in Prostate Brachytherapy

    Purpose: Prostate brachytherapy is a common treatment method for low-risk prostate cancer patients. Intraoperative treatment planning is known to improve the treatment procedure and the outcome. The current limitation of intraoperative treatment planning is the inability to localize the seeds in relation to the prostate. We developed an image-guidance system to fulfill this need to achieve intraoperative dynamic dosimetry in prostate brachytherapy. Methods: Our system is based on standard imaging equipments available in the operating room, including the transrectal ultrasound (TRUS) and the mobile C-arm. A simple fiducial is added to compute the C-arm pose. Three fluoroscopic images and an ultrasound volume of the seeds and the prostate are acquired and processed by four image processing algorithms: seed segmentation, fiducial detection with pose estimation, seed reconstruction, and seeds-to-TRUS registration. The updated seed positions allow the physician to assess the quality of implantation and dynamically adjust the treatment plan during the course of surgery to achieve improved exit dosimetry. Results: The system was tested on 10 phantoms and 37 patients. Seed segmentation resulted in a 1% false negative and 2% false positive rates. Fiducial detection with pose estimation resulted in a detection rate of 98%. Seed reconstruction had a mean reconstruction error of 0.4 mm. Seeds-to-TRUS registration had a mean registration error of 1.3 mm. The total processing time from image acquisition to registration was approximately 1 minute. Conclusion: We present an image-guidance system for intraoperative dynamic dosimetry in prostate brachytherapy. Using standard imaging equipments and a simple fiducial, our system can be easily adopted in any clinics. Robust image processing algorithms enable accurate and fast computation of the delivered dose. Especially, the system enables detection of possible hot/cold spots during the surgery, allowing the physician to address these

  1. Single-Antenna Microwave Ablation Under Contrast-Enhanced Ultrasound Guidance for Treatment of Small Renal Cell Carcinoma: Preliminary Experience

    The purpose of this study was to determine the safety, effectiveness, and feasibility of microwave ablation (MWA) of small renal cell carcinomas (RCCs) in selected patients. Institutional review board and informed consent were obtained. From December 2007 to January 2009, 12 patients (8 male, 4 female) were enrolled in a treatment group, in which percutaneous MWA of small RCCs was performed under contrast-enhanced ultrasound guidance. The tumors were 1.7-2.9 cm in diameter (mean diameter, 2.0 cm).Therapeutic effects were assessed at follow-up with computed tomography. All patients were followed up for 3-14 months (mean, 6 months) to observe the therapeutic effects and complications (according to SIR classification). Assessment was carried out with CT imaging. No severe complications or unexpected side effects were observed after the MWA procedures. In all cases technical success was achieved. Clinical effectiveness was 100%; none of the patients showed recurrence on imaging. In conclusion, our preliminary results support the use of MWA for the treatment of small renal tumors. This technology can be applied in select patients who are not candidates for surgery, as an alternative to other ablative techniques.

  2. Three-dimensional(3D) Pelvic Floor Ultrasound:Transversal Imaging of Nulliparous Vagina at Different Level%未产妇阴道不同水平横断面的三维盆底超声观察

    李勤; 胡兵; 应涛

    2009-01-01

    Objective To search for an effective imaging method for the morphological observation of female pelvic support by studying 3D ultrasound image features of nulliparous vagina and perivaginal structures at different level.Methods Fifty nulliparas were examined by 3D pelvic floor ultrasonography.The appearance of vagina and perivaginal structures was observed from vaginal vault to orifice in transversal 3D reconstruction image of pelvic floor.Results Three-dimensional pelvic floor ultrasound showed cross-sectional imaging of the whole vagina clearly.The vaginal transversal morphologies were different at different level.It was lip-like in proximal vagina,butterfly-like in middle vagina and crescent-like in distal vagina.The perivaginal structures at different level were different.Perineal body was at distal vagina level,urethrovaginal septum,rectovaginal septum and paravaginal support at middle vagina level,perivaginal connective tissue at proximal vagina level.All were uniform,dense and complete.Conclusions The 3D pelvic floor ultrasound images of vagina and perivaginal structures at different level are distinct,which is valuable for the study of 3D ultrasound in female pelvic support and pelvic floor dysfunction.%目的 探讨未产妇不同水平阴道横断面及周围结构的三维盆底超声表现,为女性盆底支持结构的形态学观察提供有效的影像学方法 .方法 对50例无生育史年轻女性进行三维盆底超声检查,获得盆底横断面声像图,连续观察宫颈外口至阴道外口间阴道横断面及周围结构的声像图表现.结果 三维盆底超声清晰显示阴道全程的横断面声像图.不同水平的阴道横断面形态不同:近段阴道呈"唇形",中段阴道呈"蝶形",远段阴道呈"月牙形".不同水平的阴道周围结构不同:远段阴道水平可见会阴体,中段阴道水平可见尿道阴道隔、直肠阴道隔及阴道旁支持结构,近段阴道水平可见阴道周围结缔组织,阴道周围

  3. 3D Dynamic Echocardiography with a Digitizer

    Oshiro, Osamu; Matani, Ayumu; Chihara, Kunihiro

    1998-05-01

    In this paper,a three-dimensional (3D) dynamic ultrasound (US) imaging system,where a US brightness-mode (B-mode) imagetriggered with an R-wave of electrocardiogram (ECG)was obtained with an ultrasound diagnostic deviceand the location and orientation of the US probewere simultaneously measured with a 3D digitizer, is described.The obtained B-mode imagewas then projected onto a virtual 3D spacewith the proposed interpolation algorithm using a Gaussian operator.Furthermore, a 3D image was presented on a cathode ray tube (CRT)and stored in virtual reality modeling language (VRML).We performed an experimentto reconstruct a 3D heart image in systole using this system.The experimental results indicatethat the system enables the visualization ofthe 3D and internal structure of a heart viewed from any angleand has potential for use in dynamic imaging,intraoperative ultrasonography and tele-medicine.

  4. 基于后端扫描的三维超声成像系统%A 3D-Ultrasound Imaging System Based on Back-end Scanning Mode

    齐建; 陈益民; 丁明跃; 尉迟明

    2012-01-01

    A new scanning mode is proposed that the front-end of the probe is fixed, while the back-end makes fan-shaped, scanning movement. The new scanning mode avoided ribs drawbacks successfully, based on the new scanning mode a 3D-Ultrasound Images System is accomplished to acquire 2D data of fetusfetus fetusfetus phantom and livers and kidneys, to demonstrates the effectiveness of the new scanning mode.%提出了一种将探头前端固定,后端以恒定速度进行扇形扫描的扫描方式,可有效避免肋骨的遮挡.基于此扫描模式,搭建了一套三维超声成像系统,采集了胎儿体模和人体肝肾脏二维数据,证明了该扫描模式的有效性.

  5. Review of ultrasound image guidance in external beam radiotherapy part II: intra-fraction motion management and novel applications.

    O'Shea, Tuathan; Bamber, Jeffrey; Fontanarosa, Davide; van der Meer, Skadi; Verhaegen, Frank; Harris, Emma

    2016-04-21

    Imaging has become an essential tool in modern radiotherapy (RT), being used to plan dose delivery prior to treatment and verify target position before and during treatment. Ultrasound (US) imaging is cost-effective in providing excellent contrast at high resolution for depicting soft tissue targets apart from those shielded by the lungs or cranium. As a result, it is increasingly used in RT setup verification for the measurement of inter-fraction motion, the subject of Part I of this review (Fontanarosa et al 2015 Phys. Med. Biol. 60 R77-114). The combination of rapid imaging and zero ionising radiation dose makes US highly suitable for estimating intra-fraction motion. The current paper (Part II of the review) covers this topic. The basic technology for US motion estimation, and its current clinical application to the prostate, is described here, along with recent developments in robust motion-estimation algorithms, and three dimensional (3D) imaging. Together, these are likely to drive an increase in the number of future clinical studies and the range of cancer sites in which US motion management is applied. Also reviewed are selections of existing and proposed novel applications of US imaging to RT. These are driven by exciting developments in structural, functional and molecular US imaging and analytical techniques such as backscatter tissue analysis, elastography, photoacoustography, contrast-specific imaging, dynamic contrast analysis, microvascular and super-resolution imaging, and targeted microbubbles. Such techniques show promise for predicting and measuring the outcome of RT, quantifying normal tissue toxicity, improving tumour definition and defining a biological target volume that describes radiation sensitive regions of the tumour. US offers easy, low cost and efficient integration of these techniques into the RT workflow. US contrast technology also has potential to be used actively to assist RT by manipulating the tumour cell environment and by

  6. Review of ultrasound image guidance in external beam radiotherapy part II: intra-fraction motion management and novel applications

    O'Shea, Tuathan; Bamber, Jeffrey; Fontanarosa, Davide; van der Meer, Skadi; Verhaegen, Frank; Harris, Emma

    2016-04-01

    Imaging has become an essential tool in modern radiotherapy (RT), being used to plan dose delivery prior to treatment and verify target position before and during treatment. Ultrasound (US) imaging is cost-effective in providing excellent contrast at high resolution for depicting soft tissue targets apart from those shielded by the lungs or cranium. As a result, it is increasingly used in RT setup verification for the measurement of inter-fraction motion, the subject of Part I of this review (Fontanarosa et al 2015 Phys. Med. Biol. 60 R77-114). The combination of rapid imaging and zero ionising radiation dose makes US highly suitable for estimating intra-fraction motion. The current paper (Part II of the review) covers this topic. The basic technology for US motion estimation, and its current clinical application to the prostate, is described here, along with recent developments in robust motion-estimation algorithms, and three dimensional (3D) imaging. Together, these are likely to drive an increase in the number of future clinical studies and the range of cancer sites in which US motion management is applied. Also reviewed are selections of existing and proposed novel applications of US imaging to RT. These are driven by exciting developments in structural, functional and molecular US imaging and analytical techniques such as backscatter tissue analysis, elastography, photoacoustography, contrast-specific imaging, dynamic contrast analysis, microvascular and super-resolution imaging, and targeted microbubbles. Such techniques show promise for predicting and measuring the outcome of RT, quantifying normal tissue toxicity, improving tumour definition and defining a biological target volume that describes radiation sensitive regions of the tumour. US offers easy, low cost and efficient integration of these techniques into the RT workflow. US contrast technology also has potential to be used actively to assist RT by manipulating the tumour cell environment and by

  7. Effectiveness of evaluating tumor vascularization using 3D power Doppler ultrasound with high-definition flow technology in the prediction of the response to neoadjuvant chemotherapy for T2 breast cancer: a preliminary report

    The aim of this study was to evaluate the effectiveness of advanced ultrasound (US) imaging of vascular flow and morphological features in the prediction of a pathologic complete response (pCR) and a partial response (PR) to neoadjuvant chemotherapy for T2 breast cancer.Twenty-nine consecutive patients with T2 breast cancer treated with six courses of anthracycline-based neoadjuvant chemotherapy were enrolled. Three-dimensional (3D) power Doppler US with high-definition flow (HDF) technology was used to investigate the blood flow in and morphological features of the tumors. Six vascularity quantization features, three morphological features, and two vascular direction features were selected and extracted from the US images. A support vector machine was used to evaluate the changes in vascularity after neoadjuvant chemotherapy, and pCR and PR were predicted on the basis of these changes.The most accurate prediction of pCR was achieved after the first chemotherapy cycle, with an accuracy of 93.1% and a specificity of 85.5%, while that of a PR was achieved after the second cycle, with an accuracy of 79.31% and a specificity of 72.22%.Vascularity data can be useful to predict the effects of neoadjuvant chemotherapy. Determination of changes in vascularity after neoadjuvant chemotherapy using 3D power Doppler US with HDF can generate accurate predictions of the patient response, facilitating early decision-making. (paper)

  8. Effectiveness of evaluating tumor vascularization using 3D power Doppler ultrasound with high-definition flow technology in the prediction of the response to neoadjuvant chemotherapy for T2 breast cancer: a preliminary report

    Shia, Wei-Chung; Chen, Dar-Ren; Huang, Yu-Len; Wu, Hwa-Koon; Kuo, Shou-Jen

    2015-10-01

    The aim of this study was to evaluate the effectiveness of advanced ultrasound (US) imaging of vascular flow and morphological features in the prediction of a pathologic complete response (pCR) and a partial response (PR) to neoadjuvant chemotherapy for T2 breast cancer. Twenty-nine consecutive patients with T2 breast cancer treated with six courses of anthracycline-based neoadjuvant chemotherapy were enrolled. Three-dimensional (3D) power Doppler US with high-definition flow (HDF) technology was used to investigate the blood flow in and morphological features of the tumors. Six vascularity quantization features, three morphological features, and two vascular direction features were selected and extracted from the US images. A support vector machine was used to evaluate the changes in vascularity after neoadjuvant chemotherapy, and pCR and PR were predicted on the basis of these changes. The most accurate prediction of pCR was achieved after the first chemotherapy cycle, with an accuracy of 93.1% and a specificity of 85.5%, while that of a PR was achieved after the second cycle, with an accuracy of 79.31% and a specificity of 72.22%. Vascularity data can be useful to predict the effects of neoadjuvant chemotherapy. Determination of changes in vascularity after neoadjuvant chemotherapy using 3D power Doppler US with HDF can generate accurate predictions of the patient response, facilitating early decision-making.

  9. Feasibility of Remote Real-Time Guidance of a Cardiac Examination Performed by Novices Using a Pocket-Sized Ultrasound Device

    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.

  10. 3D vector flow imaging

    Pihl, Michael Johannes

    The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... conventional methods can estimate only the axial component. Several approaches for 3D vector velocity estimation have been suggested, but none of these methods have so far produced convincing in vivo results nor have they been adopted by commercial manufacturers. The basis for this project is the Transverse...... on the TO fields are suggested. They can be used to optimize the TO method. In the third part, a TO method for 3D vector velocity estimation is proposed. It employs a 2D phased array transducer and decouples the velocity estimation into three velocity components, which are estimated simultaneously based on 5...

  11. Preliminary study of 3D ultrasound in visualization of levator hiatus in intrapartum women%分娩期女性盆膈裂孔三维超声影像学观察

    陶均佳; 应涛; 杨少玲; 赵奕文; 金秀红; 潘莉华

    2014-01-01

    Objective To visualize the pelvic floor structures by translabial three‐dimensional(3D) ultrasonography performed during labor and immediately after delivery, and to observe the morphological changes of levator hiatus in intrapartum women. Methods Totally 62 nulliparous women with singleton pregnancy and cephalic presentation in labor ward underwent intrapartum translabial 3D ultrasound examination before cervical dilatation, at 10 cm dilatation and immediately after delivery. Volume datasets were obtained at rest, biometric measurements and observation of the morphological changes of levator hiatus in different stages were determined in the axial plane. Comparative analyses of parameters in three stages were carried out. Results Translabial 3D ultrasound demonstrated the pelvic floor structures of intrapartum women well. All biometric measurements of the hiatus before cervical dilatation were the smallest and became the largest at 10 cm dilatation, showed statistically significant differences. The measurements after delivery got smaller immediately but still significantly larger than those before cervical dilatation ( P <0 0.01). Conclusions Translabial 3D ultrasound examination of the pelvic floor during labor and within the first 2h after delivery is feasible. It seems to be an effective tool to visualize pelvic floor structures in intrapartum women. Hiatal enlargement may be a common consequence of vaginal childbirth.%目的:应用经会阴盆底三维超声观察分娩期不同阶段女性盆膈裂孔的形态学变化。方法选取阴道试产的单胎初产妇62例,分别采集静息状态下宫口未开、宫口开全及产后即刻3个阶段的盆底三维超声容积数据。在最小盆膈裂孔平面进行超声形态学观察及参数测量,包括盆膈裂孔前后径、左右径、面积及周长。结果经会阴三维超声可较好地显示分娩不同阶段的女性盆底结构。盆膈裂孔的前后径、左右径、面积及周长均

  12. The European Society of Therapeutic Radiology and Oncology-European Institute of Radiotherapy (ESTRO-EIR) report on 3D CT-based in-room image guidance systems: A practical and technical review and guide

    The past decade has provided many technological advances in radiotherapy. The European Institute of Radiotherapy (EIR) was established by the European Society of Therapeutic Radiology and Oncology (ESTRO) to provide current consensus statement with evidence-based and pragmatic guidelines on topics of practical relevance for radiation oncology. This report focuses primarily on 3D CT-based in-room image guidance (3DCT-IGRT) systems. It will provide an overview and current standing of 3DCT-IGRT systems addressing the rationale, objectives, principles, applications, and process pathways, both clinical and technical for treatment delivery and quality assurance. These are reviewed for four categories of solutions; kV CT and kV CBCT (cone-beam CT) as well as MV CT and MV CBCT. It will also provide a framework and checklist to consider the capability and functionality of these systems as well as the resources needed for implementation. Two different but typical clinical cases (tonsillar and prostate cancer) using 3DCT-IGRT are illustrated with workflow processes via feedback questionnaires from several large clinical centres currently utilizing these systems. The feedback from these clinical centres demonstrates a wide variability based on local practices. This report whilst comprehensive is not exhaustive as this area of development remains a very active field for research and development. However, it should serve as a practical guide and framework for all professional groups within the field, focussed on clinicians, physicists and radiation therapy technologists interested in IGRT.

  13. Ultrasound -- Pelvis

    Full Text Available ... uterine cavity . Three-dimensional (3-D) ultrasound permits evaluation of the uterus and ovaries in planes that ... physicians with expertise in several radiologic areas. Outside links: For the convenience of our users, RadiologyInfo .org ...

  14. Comparison of per rectum two-dimensional and three-dimensional ultrasound guidance in prostatic systematicness puncture biopsy%经直肠二维及三维超声引导下前列腺系统性穿刺的比较

    常莹; 杨敬春; 王萍

    2014-01-01

    Objective To compare the positive rate of per rectum two-dimensional and three-dimensional ultrasound guidance in prostatic systematicness puncture biopsy, to evaluate the value of clinical application of the two methods. Methods 60 patients with digital rectal examination or abnormal of prostatic specific antigen(PSA) (> 4.0ng/mL)without past medical history of prostate cancer were divided into two groups who were respectively actualized on prostatic systematicness puncture biopsy of two-dimensional and three-dimensional ultrasound guidance. Results The positive rate of prostatic cancer of 3D-TRUS(50.0%)in prostatic systematicness puncture biopsy was higher than which of 2D-TRUS(36.7%)(P=0.001), the number of positive needles of 3D-TRUS was obviously higher than which of 2D-TRUS(P=0.000). Conclusion The positive rate of 3D-TRUS in prostatic systematicness puncture biopsy was higher than which of 2D-TRUS.%目的:比较经直肠二维及三维超声引导下前列腺穿刺活检的阳性率,评价这两种方法在临床应用中的价值。方法选取既往无前列腺癌病史的60例直肠指检或者前列腺特异抗原(PSA)异常(>4.0ng/mL)的患者,随机分为两组,分别行2D-TRUS及3D-TRUS超声引导下的穿刺活检。结果3D-TRUS引导下的前列腺穿刺活检,其前列腺癌的阳性检出率高于2D-TRUS(50.0%∶36.7%),P=0.001,3D-TRUS阳性针数的比例明显高于2D-TRUS,P=0.000。结论3D-TRUS超声引导下的前列腺穿刺活检阳性检出率明显高于2D-TRUS。

  15. 3D video

    Lucas, Laurent; Loscos, Céline

    2013-01-01

    While 3D vision has existed for many years, the use of 3D cameras and video-based modeling by the film industry has induced an explosion of interest for 3D acquisition technology, 3D content and 3D displays. As such, 3D video has become one of the new technology trends of this century.The chapters in this book cover a large spectrum of areas connected to 3D video, which are presented both theoretically and technologically, while taking into account both physiological and perceptual aspects. Stepping away from traditional 3D vision, the authors, all currently involved in these areas, provide th

  16. 3D Animation Essentials

    Beane, Andy

    2012-01-01

    The essential fundamentals of 3D animation for aspiring 3D artists 3D is everywhere--video games, movie and television special effects, mobile devices, etc. Many aspiring artists and animators have grown up with 3D and computers, and naturally gravitate to this field as their area of interest. Bringing a blend of studio and classroom experience to offer you thorough coverage of the 3D animation industry, this must-have book shows you what it takes to create compelling and realistic 3D imagery. Serves as the first step to understanding the language of 3D and computer graphics (CG)Covers 3D anim

  17. In vivo cytological observation of liver and spleen by using high-resolution microendoscopy system under endoscopic ultrasound guidance: A preliminary study using a swine model

    Suzuki, Rei; Shin, Dongsuk; Richards-Kortum, Rebecca; Coghlan, Lezlee; Bhutani, Manoop S.

    2016-01-01

    Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is useful to obtain specimens from lesions underlying deep parts of the liver and spleen. However, the development of novel ancillary techniques must be explored to reduce the number of needle passes and potential adverse effects during this procedure. We conducted an animal study using a swine to demonstrate technical feasibility of in vivo cytological observation of liver and spleen using the high-resolution microendoscopy (HRME) system under EUS guidance. We successfully performed the study. No significant acute adverse events occurred during the procedure. The HRME system could obtain clear images representing cytology-level morphology of spleen and liver. Hence, it is found out that in vivo cytological observation of liver and spleen using the HRME system under EUS guidance is technically feasible. PMID:27503155

  18. Usefulness of US-CT 3D dual imaging for the planning and monitoring of hepatocellular carcinoma treatment using HIFU

    Purpose: We evaluated the safety and usefulness of high-intensity focused ultrasound (HIFU) assisted by ultrasound-computed tomography three-dimensional (US-CT 3D) dual imaging for the treatment of hepatocellular carcinoma (HCC). Materials and methods: HIFU ablation was performed in 13 patients with small HCC (≤3 lesions, ≤3 cm in diameter). The HIFU system (Chongqing Haifu Tech) was used under ultrasound guidance. By transferring the sagittal or axial plane of the 3D US and the CT volume data into the ZioM900, multiplanar reconstruction images were displayed in a manner resembling conventional monitor US to assist the HIFU treatment. Results: Overall, 69% (9/13) of the patients in whom good visualization using B-mode sonography could not be obtained because of the influence of multi-reflections, rib shadows, and unclear tumor margins were successfully treated under the guidance of US-CT 3D dual imaging. In 5 of the 13 patients, multi-reflections were responsible for the poor visualization. In 2 cases, the tumor was poorly visualized because of a rib shadow. In one case, the margin of the tumor was too unclear to be detected using ultrasography. The 3D US images obtained as part of the US-CT 3D dual imaging had a high resolution and were useful for examining the area of HCC invasion and for determining the extent of the ablation area. The CT images, which are not influenced by bone shadows or multi-reflections, were useful for detecting the tumors and for visualizing the presence of the intestines in the sonication zone. HIFU treatments were successfully performed in all the patients with the assistance of US-CT 3D dual imaging. Conclusion: US-CT 3D dual imaging is useful for HIFU treatment for HCC, compensating for the occasionally poor visualization provided by US monitor.

  19. Needle Detection Based on Phase Grouping in 3D Transrectal Ultrasound Images%基于相位编组的三维直肠超声导引图像中针检测算法研究

    邱武; 尉迟明; 张旭明; 赵四英; 丁明跃

    2011-01-01

    This paper proposes a robust and efficient needle detection method, which is used to localize and track the needle in three-dimensional (3D) transrectal ultrasound (TRUS) guided prostate therapy. First, all voxels are grouped into different line support regions (LSR) based on the outer product of adjacent voxels' gradient vectors. The needle axis is extracted by least square fitting in LSR. The needle endpoint is localized by finding an intensity drop along the needle axis. Evaluation results in synthetic da ta, tissue-mimicking agar, chicken breast phantoms and 3D TRUS patient images obtained during the prostate cryotherapy show that the proposed methods is with a relatively higher robustness and accuracy.The result of the in-vivo test also shows that our method outperformed several alternative methods in needle endpoint localization accuracy and TP rate. It is concluded that the proposed method is suitable for 3D TRUS guided prostate transperineal therapy.%本文针对三维直肠超声导引前列腺介入式治疗中,针状手术器械定位难的问题,提出了一种三维超声图像中基于三维相位编组的针检测算法.该算法首先将体素按照梯度相位角进行分组,在得到的分组中用最小二乘拟合方法进行针状物体轴线提取,然后利用轴线体素的灰度统计特性进行端点定位.提出的方法在三维模拟数据、Agar 和鸡肉假体数据,以及三维直肠超声导引前列腺冷冻治疗中采集的病人数据进行试验,获得了较高的定位精度以及鲁棒性.与其他方法比较,发现本文提出的方法从定位精度以及分割鲁棒性方面,体现了其优越性.试验结果证明本文方法可以适用于临床应用.

  20. EUROPEANA AND 3D

    D. Pletinckx

    2012-09-01

    Full Text Available The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.

  1. 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

    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.)

  2. 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

    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.)

  3. Feasibility of remote real-time guidance of a cardiac examination performed by novices using a pocket-sized ultrasound device.

    Mai, Tuan V; Ahn, David T; Phillips, Colin T; Agan, Donna L; Kimura, Bruce J

    2013-01-01

    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%) (P < 0.05). CLUE's combined SN, SP, and ACC were 0.67, 0.96, and 0.90. Technical adequacy (%) and accuracy for each abnormality (n) were LVSD (85%, 0.93, n = 5), LAE (89%, 0.74, n = 16), ULC+ (100%, 0.94, n = 5), and eCVP (78%, 0.91, n = 1). 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. PMID:24024032

  4. Solid works 3D

    This book explains modeling of solid works 3D and application of 3D CAD/CAM. The contents of this book are outline of modeling such as CAD and 2D and 3D, solid works composition, method of sketch, writing measurement fixing, selecting projection, choosing condition of restriction, practice of sketch, making parts, reforming parts, modeling 3D, revising 3D modeling, using pattern function, modeling necessaries, assembling, floor plan, 3D modeling method, practice floor plans for industrial engineer data aided manufacturing, processing of CAD/CAM interface.

  5. Embryonic staging using a 3D virtual reality system

    C.M. Verwoerd-Dikkeboom (Christine); A.H.J. Koning (Anton); P.J. van der Spek (Peter); N. Exalto (Niek); R.P.M. Steegers-Theunissen (Régine)

    2008-01-01

    textabstractBACKGROUND: The aim of this study was to demonstrate that Carnegie Stages could be assigned to embryos visualized with a 3D virtual reality system. METHODS: We analysed 48 3D ultrasound scans of 19 IVF/ICSI pregnancies at 7-10 weeks' gestation. These datasets were visualized as 3D 'holog

  6. Micromachined Ultrasonic Transducers for 3-D Imaging

    Christiansen, Thomas Lehrmann

    Real-time ultrasound imaging is a widely used technique in medical diagnostics. Recently, ultrasound systems offering real-time imaging in 3-D has emerged. However, the high complexity of the transducer probes and the considerable increase in data to be processed compared to conventional 2-D...... ultrasound imaging results in expensive systems, which limits the more wide-spread use and clinical development of volumetric ultrasound. The main goal of this thesis is to demonstrate new transducer technologies that can achieve real-time volumetric ultrasound imaging without the complexity and cost...... capable of producing 62+62-element row-column addressed CMUT arrays with negligible charging issues. The arrays include an integrated apodization, which reduces the ghost echoes produced by the edge waves in such arrays by 15:8 dB. The acoustical cross-talk is measured on fabricated arrays, showing a 24 d...

  7. Open 3D Projects

    Felician ALECU

    2010-01-01

    Full Text Available Many professionals and 3D artists consider Blender as being the best open source solution for 3D computer graphics. The main features are related to modeling, rendering, shading, imaging, compositing, animation, physics and particles and realtime 3D/game creation.

  8. 3d-3d correspondence revisited

    Chung, Hee-Joong; Dimofte, Tudor; Gukov, Sergei; Sułkowski, Piotr

    2016-04-01

    In fivebrane compactifications on 3-manifolds, we point out the importance of all flat connections in the proper definition of the effective 3d {N}=2 theory. The Lagrangians of some theories with the desired properties can be constructed with the help of homological knot invariants that categorify colored Jones polynomials. Higgsing the full 3d theories constructed this way recovers theories found previously by Dimofte-Gaiotto-Gukov. We also consider the cutting and gluing of 3-manifolds along smooth boundaries and the role played by all flat connections in this operation.

  9. IZDELAVA TISKALNIKA 3D

    Brdnik, Lovro

    2015-01-01

    Diplomsko delo analizira trenutno stanje 3D tiskalnikov na trgu. Prikazan je razvoj in principi delovanja 3D tiskalnikov. Predstavljeni so tipi 3D tiskalnikov, njihove prednosti in slabosti. Podrobneje je predstavljena zgradba in delovanje koračnih motorjev. Opravljene so meritve koračnih motorjev. Opisana je programska oprema za rokovanje s 3D tiskalniki in komponente, ki jih potrebujemo za izdelavo. Diploma se oklepa vprašanja, ali je izdelava 3D tiskalnika bolj ekonomična kot pa naložba v ...

  10. Novel 3D ultrasound image-based biomarkers based on a feature selection from a 2D standardized vessel wall thickness map: a tool for sensitive assessment of therapies for carotid atherosclerosis

    With the advent of new therapies and management strategies for carotid atherosclerosis, there is a parallel need for measurement tools or biomarkers to evaluate the efficacy of these new strategies. 3D ultrasound has been shown to provide reproducible measurements of plaque area/volume and vessel wall volume. However, since carotid atherosclerosis is a focal disease that predominantly occurs at bifurcations, biomarkers based on local plaque change may be more sensitive than global volumetric measurements in demonstrating efficacy of new therapies. The ultimate goal of this paper is to develop a biomarker that is based on the local distribution of vessel-wall-plus-plaque thickness change (VWT-Change) that has occurred during the course of a clinical study. To allow comparison between different treatment groups, the VWT-Change distribution of each subject must first be mapped to a standardized domain. In this study, we developed a technique to map the 3D VWT-Change distribution to a 2D standardized template. We then applied a feature selection technique to identify regions on the 2D standardized map on which subjects in different treatment groups exhibit greater difference in VWT-Change. The proposed algorithm was applied to analyse the VWT-Change of 20 subjects in a placebo-controlled study of the effect of atorvastatin (Lipitor). The average VWT-Change for each subject was computed (i) over all points in the 2D map and (ii) over feature points only. For the average computed over all points, 97 subjects per group would be required to detect an effect size of 25% that of atorvastatin in a six-month study. The sample size is reduced to 25 subjects if the average were computed over feature points only. The introduction of this sensitive quantification technique for carotid atherosclerosis progression/regression would allow many proof-of-principle studies to be performed before a more costly and longer study involving a larger population is held to confirm the treatment