Adaptation of visual cortex to damage of visual pathways in suprasellar tumors before and after gamma knife radiosurgery

Purpose To demonstrate that lesions of the visual pathways due to suprasellar tumors are accompanied by alterations of the visual cortex and to see if these alterations are reversible after treatment of tumors by gamma knife radiosurgery. Materials and methods In 36 patients with peri-optic tumors and defects of their visual fields and in an age-matched control group, magnetic resonance imaging was performed before and after treatment. T1 weighted images were evaluated by voxel-based morphometry and correlated to the degree of visual field defects. Results In patients, grey matter density and cortical thickness were reduced in all parts of the occipital cortex, reaching significance (p