A Study on the Evaluation of Blood Flow in Arteriovenous Shunts and Stenosis Locations Using Non-Contact Measurement

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K18190
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 90110:Biomedical engineering-related
• Research Institution: Jikei University of Health Care Sciences
• Principal Investigator: Shimazaki Takunori 滋慶医療科学大学, 医療科学部, 准教授 (80833722)
• Project Period (FY): 2022-04-01 – 2024-03-31
• Keywords: 血液透析 / 内シャント / 狭窄 / 非接触 / 早期検出 / スリル

Outline of Final Research Achievements

This study shows the reference range of normal AVF based on quantitative values obtained from the SN ratio. The reference range for normal AVF, covering 95% of the distribution among 206 subjects, was found to be from 0.18 to 2.26, with an average value of 1.19. The confusion matrix of the binary classification between the normal group and the stenosis group using supervised machine learning revealed an accuracy of 92.3% for normal AVF, an accuracy of 76.7% for stenotic AVF, an error rate of 7.7% for stenotic AVF, and an error rate of 23.3% for normal AVF, demonstrating the effectiveness of stenosis detection. Additionally, by using a heat mapping technique that converts the brightness of the puncture site into five gradations, a technique to visualize the range from mild to severe stenosis was established.

Free Research Field

血液透析

Academic Significance and Societal Importance of the Research Achievements

日本の血液透析患者は30万人を超え、高齢者では100人に1人である。透析療法には内シャントが必要だが、狭窄が問題である。内シャントの血流確保は重要で、狭窄は合併症や死を招くこともある。現在は聴診法と触診法で状態を確認しているが、非接触で狭窄を早期発見する技術の確立が求められている。内シャントに異常が確認されると、超音波診断で狭窄部位を特定し、薬剤療法や経皮的血管拡張術が行われるため、肉体的精神的負担が大きく生活の質を著しく低下させている。本研究は、非侵襲で狭窄の早期発見と狭窄部位の推定を行うことで、既存の問題解決に寄与する可能性を示した。