Three dimensional vascular ultrasound imaging.

Intravascular ultrasound (IVUS) is a new catheter-based system that produces two-dimensional (2D) images of vascular structures. Existing systems produce real-time, cross-sectional "slices" of vessels using 5.0 French (Fr) (30 MHz) and 8.0 Fr (20 MHz) IVUS catheters containing ultrasound transducers at the tip. Computerized, three-dimensional (3D) reconstruction of these 2D images using a personal computer- (PC) based image analysis system is described. A set (n = 90) of longitudinally aligned, consecutive images is sampled from a 5.0 cm vessel segment, and computerized processing creates rendered 3D images. By adjusting image density threshold and viewing angle, the morphology, location, and spatial distribution of arterial pathology can be seen. Refinements in computer hardware and software have reduced processing time and improved image resolution to the point where 3D IVUS imaging is a clinically applicable tool. Possible applications include diagnosis of complex arterial pathology, guidance of intraluminal instruments, and assessment of the effects of endovascular interventions.