Quantitative diagnostic method for liver fibrosis using multi-Rayleigh model of ultrasound B-mode image

2015 Fiscal Year Final Research Report

• Project/Area Number: 25282153
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Medical systems
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Hachiya Hiroyuki 東京工業大学, 理工学研究科, 教授 (90156349)
• Co-Investigator(Kenkyū-buntansha): HIRATA Shinnosuke 東京工業大学, 理工学研究科, 助教 (80550970)
• Co-Investigator(Renkei-kenkyūsha): YAMAGUCHI TADASHI 千葉大学, フロンティア医工学センター, 教授 (40334172)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 医用超音波 / 定量診断 / 組織鑑別診断 / びまん性肝疾患 / 肝炎 / 振幅確率密度分布 / レイリー分布 / 線維化診断

Outline of Final Research Achievements

The development of a quantitative diagnostic method for liver fibrosis using an ultrasound B-mode image is highly required because of its real-time observation and noninvasive properties. To approximate the probability density function (PDF) of echo amplitudes from a heterogeneous tissue such as liver fibrosis, we proposed a new PDF model which is called a multi-Rayleigh model. From the multi-Rayleigh model, fibrosis parameters, such as the amount of fibrotic tissue and its progressive ratio, can be extracted. To visualize fibrotic tissues, a probability imaging method for tissue characteristics based on the multi-Rayleigh model was proposed, and to improve the evaluation accuracy, a removal method for nonspeckle signals was proposed. We showed that the information on fibrotic tissue can be extracted more accurately using the fibrotic probability than using the conventional method. We conclude that the proposed method is valid for the quantitative diagnosis of liver fibrosis.

Free Research Field

医用超音波，超音波応用計測