[Theory and clinical application of functional MRI: 3D-functional brain mapping]

Functional magnetic resonance imaging (fMRI) was performed using a clinical 1.5 T MR scanner. Normal volunteers and patients with several neurological disorders were studied with somatosensory stimulation using sponge at right hand and visual stimulation using checkerboard pattern. Both fMR images by gradient echo echo planar imaging and three dimensional gradient echo images were studied. Reconstructed 3 dimensional functional brain mapping was superimposed on 3D anatomical images. Apparent signal increase was observed at contra lateral sensorimotor cortex and secondary sensory cortex with sponge stimulation. In the case of left homonymous hemianopia due to cerebral infarction, increasing signal was only observed surrounding left calcarine fissure by using stimulation of all visual field. In conclusion, fMRI and 3-D functional brain mapping has extremely high potentiality to examine pathophysiology of various neurological disorders.