北島 久視子

Kumiko KITAJIMA

東京女子医科大学第3外科

Department of Surgery III Tokyo Womens' Medical College

キーワード : Computer analyzing system , Doppler ultrasonography , Kidney transplantation, Pulsatility index , Resistive index

This study was conducted to investigate the value of duplex Doppler ultrasonography (US) in renal allografts. In cooperation with the Aloka Company, Limited, we devised a computerized system to analyze Doppler US wave forms. Blood flow patterns in 34 renal allografts were studied using Doppler US both manually, using the conventional method, and automatically, using the new system. Time since renal transplantation renged from 1 to 137 months; serum creatinine level, from 1.2 to 10.0 mg/dl. A duplex scanner with a 3.5 MHz convex transducer was used, and blood flow pattern was evaluated at the arcuate artery of the graft. Resistive index (RI) and pulsatility index (PI) were used to quantify arterial signals. The Doppler image in the US system was reproduced in the computer system. Although the wave form had to be traced manually with a trackball in the conventional US system, the new system made it possible to both trace the wave form and calculate RI and PI automatically. Indices obtained with the manual method correlated well with those obtained using the new automatic method. Furthermore, time required for tracing and calculating was one third shorter than in the conventional method. We consider this system to be reliable and, in terms of time, economical, and consequently, a very promising tool for the automatic analysis of blood flow pattern.