Prevalence of organic neuro-ophthalmologic disease in patients with functional visual loss.

PURPOSE: To determine the concurrence of various patterns of functional visual loss (FVL) and organic disease.
DESIGN: A retrospective case series in a university neuro-ophthalmology practice.
METHODS: A retrospective case series in which we reviewed the clinical histories and neuro-ophthalmologic examinations of 133 consecutive patients diagnosed with FVL between July 1999 and August 2001. Functional visual loss was defined as an apparent afferent or efferent dysfunction that was unassociated with or far out of proportion with an identifiable lesion of the visual pathways.
RESULTS: A total of 133 patients were identified. Nineteen were pediatric, and 76 were female. Fifty-six had concurrent head or eye pain. Nineteen had a recent history of trauma, and 17 had a recent surgical procedure. The most common pattern of FVL was a normal visual field in the presence of reduced visual acuity. Seventy-one patients (53%) with FVL presented with abnormal neuro-ophthalmologic examinations. Thirteen patients had central scotomata, and all had concurrent retinal or optic nerve pathology. Only 18 patients had a known disability claim pending.
CONCLUSION: Although FVL was found in patients with no pathology, it was more common to find objective abnormalities on examination. This concurrence rate underscores the clinical necessity for following patients closely despite the diagnosis of FVL. No pattern of visual field constriction was routinely predictive of ophthalmologic or neurologic pathology except the presence of a central scotoma. The presence of a central scotoma in a nonorganic visual field should alert the practitioner to search for organic pathology.