A preliminary study of human visual cortex and clinical application by functional magnetic resonance imaging

Objective This test is focused on functional magnetic resonance imaging(fMRI) of visual cortex by using echo planar imaging(EPI) and blood oxygenation level dependent(BOLD) contrast. Methods 36 normal volunteers and 17 patients with lesions at occipital lobe were included in this test. The echo planar images of the occipital area were acquired at visual stimulation and rest phases. Results The primary visual cortex was located at the bilateral calcarine cortex, which belonged to Brodmann area 17. The functional areas showed displacement due to the mass effect of lesions near calcarine cortex in 3 patients. Conclusion fMRI can be used to study human functional cortex. A preliminary location of visual cortex can be acquired through visual stimulation. The invasion of the intracranial massive lesions to functional areas the disappearance of functional activation. The mass effect of intracranial lesions may lead to deformation or displacement of the near functional areas.