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Simultaneous measurement of perfusion and oxygenation changes using a multiple gradient-echo sequence: application to human muscle study.

V Lebon·P G Carlier·C Brillault-Salvat·A Leroy-Willig
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Abstract

We have developed a magnetic resonance imaging (MRI) technique based on a multiple gradient-echo sequence designed to probe perfusion and oxygenation simultaneously within skeletal muscle. Processing of the images acquired at successive echo times (TEs) generates two functional maps: one of the signal intensity (SI) extrapolated to zero echo time, which is sensitive to perfusion; and a second one of R2*, which reflects oxygenation. An advantage of the processing procedure lies in the selection of tissue of interest through the profile of T2* decay, leading to automatic rejection of pixels containing small vessels. This allows a more specific assessment of tissue perfusion and oxygenation. This technique was demonstrated successfully during post-ischemic reactive hyperemia in human calf. A perfusion peak of 123 mL x 100 g(-)1 x min(-1) was measured immediately after ischemia, whereas R2* value showed an 11.5% decrease at the same time, essentially reflecting blood oxygenation changes. Differences in the time courses of reperfusion and re-oxygenation were observed, oxygenation presenting a slower recovery. The mechanisms responsible for such a differential dynamic response are discussed.

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AdultEcho-Planar ImagingHumansHyperemiaIschemiaMicrocirculationMuscle, SkeletalOxygenOxygen ConsumptionPlethysmographyComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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V Lebon, P G Carlier, C Brillault-Salvat, A Leroy-Willig. 1998. Simultaneous measurement of perfusion and oxygenation changes using a multiple gradient-echo sequence: application to human muscle study.. https://doi.org/10.1016/s0730-725x(98)00088-5

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