Visual processing in patients with macular hole

Macular hole is a specific disease of the central retina that affects central visual acuity and central visual field. The purpose of this study is to investigate the alteration of visual processing in patients with macular hole who had small central scotoma. Six patients with macular hole participated in this study. We used positron emission tomography (PET) to measure task-related changes in regional cerebral blood flow to identify regions of the brain activated during visual stimulation. Three tasks were performed in each eye: control task, checkerboard task, shape-discrimination task. Checkerboard stimuli caused a greater blood flow activation response in normal eyes than in affected eyes at the occipital cortex. The area involved in the macular hole appeared to be 20 mm or more anteriorly from the occipital pole. The Shape-discrimination task in affected eyes activated angular gyrus, inferoparietal lobule, and middle frontal gyrus. Our findings demonstrated greater confidence in Horton's new retinotopic map than in Holmes' retinotopic map in cortical areas involved in macular function. The dorsal pathway of the visual system was activated more than the ventral pathway in patients with macular hole.