Objective: To compare the characteristics of functional visual loss (FVL) in adults and children.
Design: Retrospective chart review.
Participants: One hundred forty patients diagnosed with FVL over a 5-year period.
Methods: Medical records of these patients were reviewed and data analyzed using statistical software.
Outcome: Demographics, underlying organic and psychiatric disease, concomitant psychosocial events, and resolution rates were studied.
Results: Functional visual loss, with or without functional overlay, was initially diagnosed in 140 patients and was, in retrospect, a correct diagnosis in 138. There were 56 (40.6%) children and 82 (59.4%) adults (mean age, 13.4 and 40.0 years). The gender ratio, incidence of concomitant psychosocial events, incidence of functional overlay, prevalence of migraine or facial pain, and proportion referred for counseling were similar in the 2 groups. Concomitant psychosocial events were primarily social in children and related to trauma in adults. Thirty-two (39.0%) adults had a history of psychiatric illness, versus 10 (17.9%) children (P = 0.008). Symptoms were bilateral in 65.0% of cases. Functional visual loss manifested as visual acuity (VA) loss only occurred in 26.1% of patients, FVL manifested as visual field (VF) loss only was present in 28.3% of patients, and FVL with loss of both VA and VF occurred in 45.6% of patients. There was no significant difference in children versus adults in the proportion of VA, VF, or both being affected. Functional visual loss with coexistent organic disease (functional overlay) was present in 16.7% of patients. Follow-up information was available for 26.1% of patients. Normalization of any one parameter occurred in 58.3% of patients and was more likely in children. Three patients (2.2%) originally felt to have solely functional disease were subsequently diagnosed with organic disease.
Conclusion: Functional visual loss is most common in teenagers, is typically bilateral, and involves both VA and VF. Normal VA was proven half the time at initial consultation. At all ages, patients were predominantly female, and one fifth had migraine, facial pain, or coexistent organic pathology. Concomitant psychosocial events were mainly social in children and related to trauma in adults. Psychiatric disease was twice as likely in adults. Normalization of visual function occurred in a majority of patients. Early-onset macular dystrophies and hereditary optic neuropathies may be misdiagnosed as FVL.