脂質低下療法による頸動脈プラーク安定化の評価 : 超音波integrated backscatter を用いたカラーマッピングシステムの開発と臨床応用

Background : The carotid plaque vulnerability is related to myocardial and cerebral infarction. We intended to develop an imaging system which enables to visualize tissue characteristics in the carotid plaques based on ultrasound integrated backscatter（IB）. And to test its clinical efficacy, effect of the statin therapy on the plaques was evaluated with our software. Methods and Results : Carotid ultrasound examination was performed and ultrasonographic RAW data of the plaques were obtained from８patients undergoing carotid artery endarterectomy. Tissue characteristics in the plaques of resected examples were compared with preoperative ultrasonic images and the tissue IB values corresponding to the specimens were determined for developing our imaging system. Using this system, Color-coded maps of plaques in the three patients were constructed before and after lipid lowing therapy. We could demonstrate that lipid fraction in each plaque decreased and fibrous or calcification fraction increased in the follow-up study. Conclusions : Changes in histology of carotid plaques by statin could visualized with our imaging system. This technique may become a useful tool for the management of atherosclerosis.