Development of low-dose dynamic myocardial CT perfusion protocol using iterative reconstruction

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K15767
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Ehime University
• Principal Investigator: Kuwahara Natsumi 愛媛大学, 医学部附属病院, 助教 (30895941)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: Dynamic 心筋 CTP / 被ばく低減 / MBF / 心筋CT perfusion / Myocardial blood flow / 逐次近似再構成

Outline of Final Research Achievements

In present study, we underwent low-dose dynamic myocardial CT perfusion (CTP) to reduce radiation dose, and compared CTP image with full iterative reconstruction (FIR) and conventional reconstruction technique. We calculated myocardial blood flow (MBF) from reconstructed CT images (CT-MBF), and compared to 13N-ammonia PET-derived MBF (PET-MBF). Additionally, we assess diagnostic performance of CT-MBF for detecting PET-significant myocardial ischemia.
In result, CT-MBF derived from FIR image showed robust correlation between PET-MBF, moreover, showed better diagnostic performance to detect PET-significant ischemia compared to conventional reconstruction technique.
In conclusion, the low-dose dynamic myocardial CTP imaging with FIR was feasible for assessing myocardial perfusion abnormality, which may lessen invasion to patients in CTP imaging than conventional protocol, and be one of aid to spread CTP protocol as myocardial perfusion assessment.

Free Research Field

放射線科

Academic Significance and Societal Importance of the Research Achievements

本研究では、被ばく低減を目的に低線量心筋dynamic CT perfusion (CTP)撮影を施行した。低被ばく心筋CTP画像を逐次近似再構成法(IR)を併用し処理した場合と従来の画像再構成法を併用し処理した場合を比較した結果、IRを併用した場合は従来法に比べて画質改善や虚血診断能改善が可能であると示唆された。低侵襲心筋CTP撮影とIRを併用した撮影法を活用することで、患者負担の軽減や、灌流評価法としてのCTPの普及の実現が期待できると考える。