Patients with left main coronary artery (LMCA) atherosclerosis have a poor prognosis compared with lesions in the other coronaries. Because of the methodological problems. LMCA atherosclerotic lesions are not frequent...Patients with left main coronary artery (LMCA) atherosclerosis have a poor prognosis compared with lesions in the other coronaries. Because of the methodological problems. LMCA atherosclerotic lesions are not frequently detected by coronary angiography. The purpose of the study was to reveal the existence of LMCA disease in patients with normal coronary arteries by using intravascular ultrasound imaging. Ninety-seven patients with angiographically normal coronary arteries were examined with a 3.5 F or 4.8 F. 20 MHz intravascular ultrasound catheter. The vessel, lumen and plaque areas were determined and percent area and diameter stenosis were calculated. Plaque formation with or without calcific deposits identified by ultrasound accoustic shadowing were regarded as signs of atherosclerosis.展开更多
In order to investigate the relationship between restenosis and the morphology detected by coronary angioscopy (CASC) and introvascular ultrasound imaging (IVUS), 17 patients were detected by CASC and IVUS immediately...In order to investigate the relationship between restenosis and the morphology detected by coronary angioscopy (CASC) and introvascular ultrasound imaging (IVUS), 17 patients were detected by CASC and IVUS immediately and 3 months after percutaneous transluminal coronary angioscopy (PTCA), The results showed that the dilation index by IVUS (DIu) was significantly lower in restenosis patients than in non-restenosis patients (0.42 +/- 0.08 versus 0.78 +/- 0.16, P < 0.01) and that the elastic recoil (ER) was higher in restenosis patients than in non-restenosis patients (4.51 +/- 1.42 mm(2) versus 1.63 +/- 1.20 mm(2), P < 0.01), and that the elastic recoil rate (ERR) was also higher in restenosis patients than in non-restenosis patients (57.3 +/- 8.07% versus 21.80 +/- 16.84% P < 0.01), and that coronary dissection, atheromatous plaque and calcification as well as the colour of inner coronary artery had no relation with chronic restenosis. In conclusion, the elastic recoil is one of the important factors of chronic restenosis after PTCA.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
The purpose of the study is to reconstruct the coronary arteries in 3 dimension (3D) from serial intravascular ultrasound (IVUS) images generated during a pullback of IVUS catheter. Slowly pullback. real-time, cross-s...The purpose of the study is to reconstruct the coronary arteries in 3 dimension (3D) from serial intravascular ultrasound (IVUS) images generated during a pullback of IVUS catheter. Slowly pullback. real-time, cross-sectional IVUS images of 18 patients (2 with normal coronary arteries. 1 with coronary aneurysm. and 15 post PTCA) were obtained by using a 20 MHz. 3.5F IVUS catheter and recorded on video tape. A series of 90-frame consecutive IVUS images were digitized into a SUN Spare 11 workstation. Digitized data were reconstructed to 3D images with use of voxel space modeling and were generated in both sagittal and cylindrical formats. The sagittal format results in a longitudinal展开更多
文摘Patients with left main coronary artery (LMCA) atherosclerosis have a poor prognosis compared with lesions in the other coronaries. Because of the methodological problems. LMCA atherosclerotic lesions are not frequently detected by coronary angiography. The purpose of the study was to reveal the existence of LMCA disease in patients with normal coronary arteries by using intravascular ultrasound imaging. Ninety-seven patients with angiographically normal coronary arteries were examined with a 3.5 F or 4.8 F. 20 MHz intravascular ultrasound catheter. The vessel, lumen and plaque areas were determined and percent area and diameter stenosis were calculated. Plaque formation with or without calcific deposits identified by ultrasound accoustic shadowing were regarded as signs of atherosclerosis.
文摘In order to investigate the relationship between restenosis and the morphology detected by coronary angioscopy (CASC) and introvascular ultrasound imaging (IVUS), 17 patients were detected by CASC and IVUS immediately and 3 months after percutaneous transluminal coronary angioscopy (PTCA), The results showed that the dilation index by IVUS (DIu) was significantly lower in restenosis patients than in non-restenosis patients (0.42 +/- 0.08 versus 0.78 +/- 0.16, P < 0.01) and that the elastic recoil (ER) was higher in restenosis patients than in non-restenosis patients (4.51 +/- 1.42 mm(2) versus 1.63 +/- 1.20 mm(2), P < 0.01), and that the elastic recoil rate (ERR) was also higher in restenosis patients than in non-restenosis patients (57.3 +/- 8.07% versus 21.80 +/- 16.84% P < 0.01), and that coronary dissection, atheromatous plaque and calcification as well as the colour of inner coronary artery had no relation with chronic restenosis. In conclusion, the elastic recoil is one of the important factors of chronic restenosis after PTCA.
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.
文摘The purpose of the study is to reconstruct the coronary arteries in 3 dimension (3D) from serial intravascular ultrasound (IVUS) images generated during a pullback of IVUS catheter. Slowly pullback. real-time, cross-sectional IVUS images of 18 patients (2 with normal coronary arteries. 1 with coronary aneurysm. and 15 post PTCA) were obtained by using a 20 MHz. 3.5F IVUS catheter and recorded on video tape. A series of 90-frame consecutive IVUS images were digitized into a SUN Spare 11 workstation. Digitized data were reconstructed to 3D images with use of voxel space modeling and were generated in both sagittal and cylindrical formats. The sagittal format results in a longitudinal