Cg. Santosh et al., FUNCTIONAL MAGNETIC-RESONANCE-IMAGING AT 1-T - MOTOR CORTEX, SUPPLEMENTARY MOTOR AREA AND VISUAL-CORTEX ACTIVATION, British journal of radiology, 68(808), 1995, pp. 369-374
Functional activation of the brain has been visualized using magnetic
resonance imaging (MRI). Early studies used echo planar imaging and ma
gnetic fields of 2 T and above. However, recent studies have successfu
lly shown the activation of visual and motor areas of the brain using
conventional clinical 1.5 T MRI systems. The purpose of the present st
udy was to replicate these studies at a lower field strength. Eight mo
tor and two visual activation studies were performed using a 1 T clini
cal scanner. Activation was seen in the contralateral motor cortex dur
ing motor stimulation in six of the eight volunteers. Activation was a
lso documented within the contralateral supplementary motor area in fo
ur of the six volunteers with motor cortex activation. The supplementa
ry motor area was located in the posteromedial aspect of the superior
frontal gyrus. Both volunteers subjected to photic stimulation showed
activation within the visual cortex. Results show that functional imag
ing can be successfully carried out with a 1 T clinical scanner. The s
ize of the image intensity on activation change suggests that contrast
may not be due solely to susceptibility changes.