Radiology, Vol 186, 353-356, Copyright © 1993 by Radiological Society of North America
Measurement of brain activity with bolus administration of contrast agent and gradient-echo MR imaging
JR Zigun, JA Frank, FA Barrios, DW Jones, TK Foo, CT Moonen, DZ Press and DR Weinberger
Clinical Brain Disorders Branch, National Institute of Mental Health, Washington, DC 20032.
This study was performed to measure changes in cerebral blood volume (CBV)
associated with visual activation by use of bolus administration of
contrast agent and conventional, clinically configured magnetic resonance
(MR) hardware and software. Fast gradient-recalled acquisition in the
steady state technique was used to study five healthy subjects during
visual activation and a control dark state. MR images were obtained every
2.048 seconds for 2 minutes. A bolus of gadopentetate dimeglumine was
injected during visual stimulation and darkness. Cine images produced from
the series of rapid images clearly depicted arterial, capillary, and venous
phases. Analysis of serial concentration maps derived from the rapid images
revealed expected differences between the relative CBV of gray matter and
that of white matter, as well as significantly increased relative CBV in
calcarine cortex during visual activation versus the control state (mean
increase, 15.24%; range, 6.41%-27.78%; P < .05). These results confirm
those reported in echo-planar imaging studies and demonstrate that brain
function can be assessed with the bolus method by means of MR imaging
hardware and software with conventional clinical configurations.
