Tissue elasticity and viscosity are always associated with pathological changes.As a new imaging method,ultrasound vibro-acoustic imaging is developed for quantitatively measuring tissue elasticity and viscosity which...Tissue elasticity and viscosity are always associated with pathological changes.As a new imaging method,ultrasound vibro-acoustic imaging is developed for quantitatively measuring tissue elasticity and viscosity which have important significance in early diagnosis of cancer.This paper developed an ultrasound vibro-acoustic imaging research platform mainly consisting of excitation part and detection part.The excitation transducer was focused at one location within the medium to generate harmonic vibration and shear wave propagation,and the detection transducer was applied to detect shear wave at other locations along shear wave propagation path using pulse-echo method.The received echoes were amplified,filtered,digitized and then processed by Kalman filter to estimate the vibration phase.According to the phase changes between different propagation locations,we estimated the shear wave speed,and then used it to calculate the tissue elasticity and viscosity.Preliminary phantom experiments based on this platform show results of phantom elasticity and viscosity close to literature values.Upcoming experiments are now in progress to obtain quantitative elasticity and viscosity in vitro tissue.展开更多
Endoscopic ultrasound (EUS) has recently evolved through technological improvement of equipment,with a major clinical impact in digestive and mediastinal diseases.State-of-the-art EUS equipment now includes real-time ...Endoscopic ultrasound (EUS) has recently evolved through technological improvement of equipment,with a major clinical impact in digestive and mediastinal diseases.State-of-the-art EUS equipment now includes real-time sono-elastography,which might be useful for a better characterization of lesions and increased accuracy of differential diagnosis (for e.g.lymph nodes or focal pancreatic lesions).Contrast-enhanced EUS imaging is also available,and is already being used for the differential diagnosis of focal pancreatic masses.The recent development of low mechanical index contrast harmonic EUS imaging offers hope for improved diagnosis,staging and monitoring of anti-angiogenic treatment.Tridimensional EUS (3D-EUS) techniques can be applied to enhance the spatial understanding of EUS anatomy,especially for improved staging of tumors,obtained through a better assessment of the relationship with major surrounding vessels.Despite the progress gained through all these imaging techniques,they cannot replace cytological or histological diagnosis.However,real-time optical histological diagnosis can be achieved through the use of single-fiber confocal laser endomicroscopy techniques placed under real-time EUS-guidance through a 22G needle.Last,but not least,EUS-assisted natural orifice transluminal endoscopic surgery (NOTES) procedures offer a whole new area of imaging applications,used either for combination of NOTES peritoneoscopy and intraperitoneal EUS,but also for access of retroperitoneal organs through posterior EUS guidance.展开更多
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 n...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 organr 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.展开更多
AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasou...AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasound image in real time by merging the ultrasound image with a multiplanar reconstruction computed tomography(CT)image,using pre-scanned CT volume data.The ultrasound used was EUB-8500with a convex probe EUP-C514.The RVS images were evaluated based on 3 levels,namely,excellent,good and poor,by the displacement in position.RESULTS:By combining the objectivity of CT with free scanning using RVS,it was possible to easily interpret the relationship between lesions and the surrounding organs as well as the position of vascular structures.The resulting evaluation levels of the RVS images were12 excellent(pancreatic cancer,bile duct cancer,cholecystolithiasis and cholangiocellular carcinoma)and 3 good(pancreatic cancer and gallbladder cancer).Compared with conventional B-mode ultrasonography and CT,RVS images achieved a rate of 80%superior visualization and 20%better visualization.CONCLUSION:RVS has potential usefulness in objective visualization and diagnosis in the field of biliary and pancreatic diseases.展开更多
The effect of the transducer eccentricity on grayscales of intravascualr ultrasound images was corrected based on the scattering properties of high frequency ultrasound in vessel walls. The displacement and strain dis...The effect of the transducer eccentricity on grayscales of intravascualr ultrasound images was corrected based on the scattering properties of high frequency ultrasound in vessel walls. The displacement and strain distributions of vessel walls produced by tissue microelement motion were obtained using a novel motion estimation method in steps and sum based on the optical flow and genetic algorithm. Furthermore, authors firstly reconstructed 'real' elasticity distribution images of cross section tissues of vessel walls in the world. In vitro experimental results of porcine artery demonstrated the methods mentioned above are reasonable. Experimental investigation of vascular mechanics can be advanced to 2D sub-millimeter microstructure levels. These studies have potential to provide new technology means in monitoring and evaluation of Percutaneous transluminal coronary angioplasty process.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.81000637)the Key Program of National Natural Science Foundation of China(Grant No.61031003)Shenzhen-HK innovative circle project(Grant No.ZYB200907090125A).
文摘Tissue elasticity and viscosity are always associated with pathological changes.As a new imaging method,ultrasound vibro-acoustic imaging is developed for quantitatively measuring tissue elasticity and viscosity which have important significance in early diagnosis of cancer.This paper developed an ultrasound vibro-acoustic imaging research platform mainly consisting of excitation part and detection part.The excitation transducer was focused at one location within the medium to generate harmonic vibration and shear wave propagation,and the detection transducer was applied to detect shear wave at other locations along shear wave propagation path using pulse-echo method.The received echoes were amplified,filtered,digitized and then processed by Kalman filter to estimate the vibration phase.According to the phase changes between different propagation locations,we estimated the shear wave speed,and then used it to calculate the tissue elasticity and viscosity.Preliminary phantom experiments based on this platform show results of phantom elasticity and viscosity close to literature values.Upcoming experiments are now in progress to obtain quantitative elasticity and viscosity in vitro tissue.
基金Supported by "Utility of EUS and OCT for the minimal invasive evaluation of tumour neo-angiogenesis in the patients with digestive cancers" financed by the Romanian Ministry of Educationand Research-National University Research Council UEFISCSU-Ideas Program, No.239/2007
文摘Endoscopic ultrasound (EUS) has recently evolved through technological improvement of equipment,with a major clinical impact in digestive and mediastinal diseases.State-of-the-art EUS equipment now includes real-time sono-elastography,which might be useful for a better characterization of lesions and increased accuracy of differential diagnosis (for e.g.lymph nodes or focal pancreatic lesions).Contrast-enhanced EUS imaging is also available,and is already being used for the differential diagnosis of focal pancreatic masses.The recent development of low mechanical index contrast harmonic EUS imaging offers hope for improved diagnosis,staging and monitoring of anti-angiogenic treatment.Tridimensional EUS (3D-EUS) techniques can be applied to enhance the spatial understanding of EUS anatomy,especially for improved staging of tumors,obtained through a better assessment of the relationship with major surrounding vessels.Despite the progress gained through all these imaging techniques,they cannot replace cytological or histological diagnosis.However,real-time optical histological diagnosis can be achieved through the use of single-fiber confocal laser endomicroscopy techniques placed under real-time EUS-guidance through a 22G needle.Last,but not least,EUS-assisted natural orifice transluminal endoscopic surgery (NOTES) procedures offer a whole new area of imaging applications,used either for combination of NOTES peritoneoscopy and intraperitoneal EUS,but also for access of retroperitoneal organs through posterior EUS guidance.
文摘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 organr 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.
文摘AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasound image in real time by merging the ultrasound image with a multiplanar reconstruction computed tomography(CT)image,using pre-scanned CT volume data.The ultrasound used was EUB-8500with a convex probe EUP-C514.The RVS images were evaluated based on 3 levels,namely,excellent,good and poor,by the displacement in position.RESULTS:By combining the objectivity of CT with free scanning using RVS,it was possible to easily interpret the relationship between lesions and the surrounding organs as well as the position of vascular structures.The resulting evaluation levels of the RVS images were12 excellent(pancreatic cancer,bile duct cancer,cholecystolithiasis and cholangiocellular carcinoma)and 3 good(pancreatic cancer and gallbladder cancer).Compared with conventional B-mode ultrasonography and CT,RVS images achieved a rate of 80%superior visualization and 20%better visualization.CONCLUSION:RVS has potential usefulness in objective visualization and diagnosis in the field of biliary and pancreatic diseases.
基金This work was supported by the National Science Foundation of China(No.69925101,39970208).
文摘The effect of the transducer eccentricity on grayscales of intravascualr ultrasound images was corrected based on the scattering properties of high frequency ultrasound in vessel walls. The displacement and strain distributions of vessel walls produced by tissue microelement motion were obtained using a novel motion estimation method in steps and sum based on the optical flow and genetic algorithm. Furthermore, authors firstly reconstructed 'real' elasticity distribution images of cross section tissues of vessel walls in the world. In vitro experimental results of porcine artery demonstrated the methods mentioned above are reasonable. Experimental investigation of vascular mechanics can be advanced to 2D sub-millimeter microstructure levels. These studies have potential to provide new technology means in monitoring and evaluation of Percutaneous transluminal coronary angioplasty process.
