Functional brain MR imaging based on bolus tracking with a fast T2∗-sensitized gradient-echo method
Magnetic Resonance ImagingPublished 1 January 1994
Chrit Moonen, Fernando A. Barrios, Jeffrey R. Zigun, Joe Gillen, Guoying Liu, Geoffrey Sobering
Citations39
SJR quartileQ2
SJR score0.63
SNIP0.79
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TL;DR
It is shown that the T2* sensitivity of conventional FLASH techniques can be improved drastically on a conventional whole body instrument by delaying the gradient-echo until the subsequent TR-period without increasing total imaging time.
Abstract
Dynamic physiological scanning, based on temporary changes in local field homogeneity during the passage of a contrast agent bolus, has been performed hitherto with echo-planar imaging (EPI) or conventional gradient-recalled techniques (FLASH). Here, it is shown that the T2* sensitivity of conventional FLASH techniques can be improved drastically on a conventional whole body instrument by delaying the gradient-echo until the subsequent TR-period without increasing total imaging time. Examples are given for a full k-space matrix (128 x 256) obtained within 2 s with a TE of 25 ms, resulting in images free of artifacts. The method is applied to bolus tracking through the brain of healthy volunteers during visual stimulation and in the dark. An average increase of regional cerebral blood volume (rCBV) in the visual cortex of 10.9% (n = 9, p = .001) was found.
Keywords
MedicinePhysics and Astronomy
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