Failure of the Clinical Examination to Predict the Presence of Functional Vision.

The absence of a pupillary light reflex and the lack of any clinical response to visual stimulation are generally considered reliable signs of poor visual function in patients with abnormal mental status. Two case reports are presented, one with no pupillary light reflex and no response to visual stimuli; and another with no clinical response to visual stimulation. After several months with no signs of vision, both patients regained significant visual function. It is important to recognize that all signs of visual function can be absent despite the potential for good vision. This should be considered before concluding that visual loss will be permanent.