Insights into hippocampal perfusion using high-resolution, multi-modal 7T MRI

• 成果类型: Article
• 署名作者: Haast, Roy A. M.; Kashyap, Sriranga; Ivanov, Dimo; Yousif, Mohamed D.; Dekraker, Jordan; Poser, Benedikt A.; Khan, Ali R.
• 署名单位: Western University (University of Western Ontario); University Western Ontario Hospital; Maastricht University; Krembil Research Institute; University of Toronto; University Health Network Toronto; McGill University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-15413
• DOI: 10.1073/pnas.2310044121
• 发表日期: 2024-03-12
• 关键词: concurrent functional perfusion; temporal-lobe epilepsy; spin-labeling mri; resting state; human brain; high-field; arterial; blood; segmentation; ORGANIZATION

摘要

We present a comprehensive study on the non-invasive measurement of hippocampal perfusion. Using high-resolution 7 tesla arterial spin labeling (ASL) data, we generated robust perfusion maps and observed significant variations in perfusion among hippocampal subfields, with CA1 exhibiting the lowest perfusion levels. Notably, these perfusion differences were robust and already detectable with 50 perfusionweighted images per subject, acquired in 5 min. To understand the underlying factors, we examined the influence of image quality metrics, various tissue microstructure and morphometric properties, macrovasculature, and cytoarchitecture. We observed higher perfusion in regions located closer to arteries, demonstrating the influence of vascular proximity on hippocampal perfusion. Moreover, ex vivo cytoarchitectonic features based on neuronal density differences appeared to correlate stronger with hippocampal perfusion than morphometric measures like gray matter thickness. These findings emphasize the interplay between microvasculature, macrovasculature, and metabolic demand in shaping hippocampal perfusion. Our study expands the current understanding of hippocampal physiology and its relevance to neurological disorders. By providing in vivo evidence of perfusion differences between hippocampal subfields, our findings have implications for diagnosis and potential therapeutic interventions. In conclusion, our study provides a valuable resource for extensively characterizing hippocampal perfusion.