MR imaging of microcirculation in rat brain: Correlation with carbon dioxide-induced changes in blood flow

✍ Scribed by Jeffrey H. Maki; Helene Benveniste; James R. Macfall; Claude A. Piantadosi; G. Allan Johnson

• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: English
• Weight: 932 KB
• Volume: 1
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.1880010609

✦ Synopsis

Abstract

Considerable interest has been shown in developing a magnetic resonance (MR) imaging technique with quantitative capability in the evaluation of tissue microcirculation (“perfusion”). In the present study, the flow‐dephased/flow‐compensated (FD/FC) technique is evaluated for measuring rat cerebral blood flow (CBF) under nearly optimal laboratory conditions. Imaging was performed on a 2.O‐T system equipped with shielded gradient coils. Rat CBF was varied by manipulating arterial carbon dioxide pressure (Paco^2^). In parallel experiments, optimized MR imaging studies (seven rats) were compared with laser Doppler flowmetry (LDF) studies (nine rats). LDF values showed a high degree of correlation between CBF and Paco~2~, agreeing with results in the literature. MR imaging values, while correlating with Paco~2~, showed considerable scatter. The most likely explanation is unavoidable rat motion during the requisite long imaging times. Because of this motion sensitivity, the FD/FC technique cannot provide a quantitative measure of CBF. It can, however, provide a qualitative picture.