胃粘膜血流の画像解析

The Functional Imaging of Gastric Mucosal Hemodynamics

要旨　消化性潰瘍の発生・治癒の病態生理を解明すると共に，内視鏡による潰瘍の客観的診断法の開発を目的に，内視鏡下に粘膜血流や代謝機能を計測し，肉眼視できない粘膜微小循環系の画像化システムを開発した．ヒト胃潰瘍活動期には胃粘膜血液量分布図は潰瘍周辺で低下するパターンをとり，このパターンは治癒期には逆転し潰瘍周辺でむしろ増加した．更に近年開発された電子内視鏡を用い，リアルタイムに胃粘膜の血流機能画像を作成した．本システムは既に臨床応用を開始しており，臨床例について紹介した．

　Recent advances in image processing techniques are ushering in a new era of endoscopic diagnosis for peptic ulcers. In this paper, we report the usefulness of functional imaging in the analysis of gastric mucosal hemodynamics as an important defensive factor against aggressive agents.

　“Organ reflectance spectrophotometry” enabled the rapid and multiple measurement of regional blood volume. We made a computer-aided display of the distribution in gastric mucosal blood volume. These functional images were useful for analyzing the ab-normality of regional hemodynamics and predicting the appearance of acute gastric mucosal lesions and the healing of chronic gastric ulcers.

　The electric signals of the newly developed videoendoscope suited the image processing unit. We found that it was possible to analyze regional he-modynamics directly from the endoscopic image using a processing technique called “feature extraction”.

　Thus, we concluded that the functional imaging of gastric mucosal hemodynamics should be regarded as important progress in endoscopic diagnosis of peptic ulcers.