Traumatic bilateral homonymous hemianopic scotomas

A patient is presented who received a gunshot wound that injured both occipital poles. It resulted in a central scotoma that was due to the combined effect of both right and left homonymous hemianopic scotomas. A 15 degrees wedge of retained, functioning, central field permitted the retention of 20/20 visual acuity. This case illustrates the point that only a small portion of the central fixation area need to be retained in order to maintain normal central visual acuity. We stress the diagnostic significance of vertical steps demonstrated with central scotomas as an indication that the field defect is due to retrochiasmal disease rather than bilateral macular or optic nerve disease.