Cerebral circulation measurement by ASL imaging: arterial transit time and arterial transit artifact

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K09942
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Akita Cerebrospinal and Cardiovascular Center
• Principal Investigator: Ibaraki Masanobu 秋田県立循環器・脳脊髄センター(研究所), 放射線医学研究部, 主任研究員 (40360359)
• Co-Investigator(Kenkyū-buntansha): 中村 和浩 秋田県立循環器・脳脊髄センター(研究所), 放射線医学研究部, 主任研究員 (10312638) ; 梅津 篤司 東北大学, 大学病院, 助教 (40370259)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: ASL / CBF / PET / 脳循環 / 到達時間

Outline of Final Research Achievements

Pseudo-continuous arterial spin labeling (pCASL) is a completely non-invasive method of cerebral perfusion measurement. However, cerebral blood flow (CBF) quantification is hampered by arterial transit artifacts characterized by bright vascular signals surrounded by decreased signals in tissue regions, which commonly appear in patients with reduced cerebral perfusion pressure. Alternatively, ATT-like information can be extracted by calculating the spatial CoV from pCASL CBF images with single-PLD acquisition. The present study demonstrated the correlations between the spatial CoV determined by pCASL and PET-based measures for a patient group with cerebrovascular steno-occlusive disease. This method, although it is currently an ROI-based assessment, is feasible in clinical settings without the need for time-consuming, multi-timing ASL scans and can potentially detect subtle perfusion abnormalities.

Free Research Field

脳循環イメージング

Academic Significance and Societal Importance of the Research Achievements

本研究は，PETとの比較を通して，非造影MRIの一手法である動脈血スピンラベリング法（Arterial Spin Labeling; ASL）の脳循環評価手法としての可能性・臨床的有用性を明らかにすることを目的としたものである。片側性脳主幹動脈狭窄閉塞症例を対象とした解析により，ASL画像から計算される画像変動指標（spatial coefficient of variation; sCoV）は脳循環パラメータとして利用可能であり，より敏感に循環異常を検出できる臨床ツールと成り得る可能性が示された。