Comparing single- and multi-post labeling delays for the measurements of resting cerebral and hippocampal blood flow for cerebrovascular testing in midlife adults
Date
2024-10-01
Journal Title
Journal ISSN
Volume Title
Publisher
Frontiers in Physiology
Abstract
Objectives: To assess the reliability and validity of measuring resting cerebral blood flow (CBF) and hippocampal CBF using a single-post-labeling delay (PLD) and a multi-PLD pseudo-continuous arterial spin labeling (pCASL) protocol for cerebrovascular reactivity (CVR) testing.
Methods: 25 healthy, midlife adults (57 ± 4 years old) were imaged in a Siemens Prisma 3T magnetic resonance imaging (MRI) scanner. Resting CBF and hippocampal CBF were assessed using two pCASL protocols, our modified single-PLD protocol (pCASL-MOD) to accommodate the needs for CVR testing and the multi-PLD Human Connectome Project (HCP) Lifespan protocol to serve as the reference control (pCASL-HCP). During pCASL-MOD, CVR was calculated as the change in CBF from rest to hypercapnia (+9 mmHg increase in end-tidal partial pressure of carbon dioxide [PETCO2]) and then normalized for PETCO2. The reliability and validity in resting gray matter (GM) CBF, white matter (WM) CBF, and hippocampal CBF between pCASL-MOD and pCASL-HCP protocols were examined using correlation analyses, paired t-tests, and Bland Altman plots.
Results: The pCASL-MOD and pCASL-HCP protocols were significantly correlated for resting GM CBF [r = 0.72; F (1, 23) = 25.24, p < 0.0001], WM CBF [r = 0.57; F (1, 23) = 10.83, p = 0.003], and hippocampal CBF [r = 0.77; F (1, 23) = 32.65, p < 0.0001]. However, pCASL-MOD underestimated resting GM CBF (pCASL-MOD: 53.7 ± 11.1 v. pCASL-HCP: 69.1 ± 13.1 mL/100 g/min; p < 0.0001), WM CBF (pCASL-MOD: 32.4 ± 4.8 v. pCASL-HCP: 35.5 ± 6.9 mL/100 g/min; p = 0.01), and hippocampal CBF (pCASL-MOD: 50.5 ± 9.0 v. pCASL-HCP: 68.1 ± 12.5 mL/100 g/min; p < 0.0001). PETCO2 increased by 8.0 ± 0.7 mmHg to induce CVR (GM CBF: 4.8% ± 2.6%; WM CBF 2.9% ± 2.5%; and hippocampal CBF: 3.4% ± 3.8%).
Conclusion: Our single-PLD pCASL-MOD protocol reliably measured CBF and hippocampal CBF at rest given the significant correlation with the multi-PLD pCASL-HCP protocol. Despite the lower magnitude relative to pCASL-HCP, we recommend using our pCASL-MOD protocol for CVR testing in which an exact estimate of CBF is not required such as the assessment of relative change in CBF to hypercapnia.
Description
This article was originally published in Frontiers in Physiology by Frontiers Media. The version of record is available at: https://doi.org/10.3389/fphys.2024.1437973
© 2024 Decker, Sanjana, Rizzi, Kramer, Cerjanic, Johnson and Martens. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Keywords
brain health, cerebral blood flow (CBF), cerebrovascular reactivity (CVR), magnetic resonance imaging (MRI), and arterial spin labeling (ASL) MRI
Citation
Decker KP, Sanjana F, Rizzi N, Kramer MK, Cerjanic AM, Johnson CL and Martens CR (2024) Comparing single- and multi-post labeling delays for the measurements of resting cerebral and hippocampal blood flow for cerebrovascular testing in midlife adults. Front. Physiol. 15:1437973. doi: 10.3389/fphys.2024.1437973