Elucidation of the Mechanism of Cognitive Dysfunction caused by Cerebral Hyperperfusion after Carotid Endarterectomy using 7T Quantitative Susceptibility Mapping.

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K16735
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Iwate Medical University
• Principal Investigator: Yoshida Jun 岩手医科大学, 医学部, 助教 (50869047)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 頚部頚動脈狭窄症 / 鉄沈着 / 7 Tesla MRI / 認知機能 / 過灌流 / 定量的磁化率マッピング / 頚動脈内膜剥離術

Outline of Final Research Achievements

This study aimed to detect and quantify iron deposition before and after carotid endarterectomy (CEA) in a case exhibiting postoperative hyperperfusion using quantitative susceptibility mapping (QSM) with ultra-high-field human 7 Tesla MRI (7TMRI), and to investigate its association with cognitive impairment.

Although our facility's 7TMRI QSM can assess iron deposition in the cortical surface of the entire brain, the disadvantage of strong image distortion became evident with the multi-echo method on 7TMRI images. Therefore, we opted to first perform imaging with less distortion using 3 Tesla MRI (3TMRI) compared to 7TMRI. 3TMRI QSM yielded images with minimal distortion and appropriate quality. The research findings revealed that preoperative cortical magnetization and postoperative changes in cerebral blood flow were associated with cognitive improvement after CEA. We compiled the paper at our department, and it was published in Cerebrovascular Disease in February 2024.

Free Research Field

脳血管障害

Academic Significance and Societal Importance of the Research Achievements

本研究により、術前の鉄沈着の程度によりCEA後に認知機能が改善する事が予測でき、手術治療を行う事での利益を術前からの把握する事が可能となる。この事実は患者が手術の結果をより正確に理解した上で同意の判断を可能とすると考える。また、3TMRIにて適切なQSM画像を安定して作成する事が出来た。今後は7TMRIQSMの歪みの問題を解消して、7TMRIでのより高精細なQSM画像を作成する事を目標とする。その結果が認知機能改善に対する予測精度のさらなる上昇に寄与するものと考える。