Medically unexplained visual loss in a specialist clinic: a retrospective case–control comparison

Abstract Purpose To compare the clinical and demographic characteristics of adult patients with nonorganic or medically unexplained visual loss (MUVL) to those with other common conditions presenting to a neuro-ophthalmology clinic. Methods Case–control design: a retrospective review of medical notes on a consecutive case series of 49 patients assessed at the King's College Hospital neuro-ophthalmology clinic with unexplained visual loss and matched with the next assessed patient identified from clinic records. Patients presented post-symptom onset with a mean clinical course of 30 months (SD = 67 months) and standard clinical examination used to confirm diagnoses, alongside ancillary investigations if required. Results Seventy-two percent (n = 36) of MUVL patients were female. In comparison with patients with organic visual disorders, MUVL cases presented with significantly higher rates of bilateral (cf. unilateral) visual impairment (41%, n = 20), premorbid psychiatric (27%, n = 13) as well as functional (24%, n = 12) diagnoses and psychotropic medication usage (22%, n = 11). Medically unexplained cases were significantly more likely to report preceding psychological stress (n = 9; 18%). Conclusions Medically unexplained visual impairment may be regarded as part of the spectrum of medically unexplained disorders seen in the general hospital setting. Research is needed to determine long-term outcomes and effective tailored interventions.