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Diagnostic and therapeutic challenges.

A 41-year-old Japanese woman presented to the Medical Retina Department of the Birmingham and Midland Eye Centre reporting chronic photopsia and visual field loss. Previously, she had undergone extensive neurologic, medical, and ophthalmologic consultations and laboratory investigations elsewhere, but no definitive diagnosis had been made to account for her symptoms. Nine years earlier, she initially reported flashing lights in front of her right eye and progressive ‘‘tunnel vision’’ of this eye. The attending ophthalmologist in Japan made a diagnosis of retinitis pigmentosa (RP). On moving to the UK later in the same year, she sought further ophthalmic assessment because of ongoing symptoms in her right eye. At this point, best-corrected visual acuity was 20/20 in each eye, near visual acuity N4.5 in each eye, and color vision normal. Ocular and medical history was remarkable only for myopia and an episode of abdominal shingles occurring 10 years before the development of her ocular complaints. There was no significant family history. Goldmann visual fields were markedly constricted in the right eye (limited to 30 around fixation) but were normal in the left eye. On examination, there was evidence of mild vitritis in each eye, accompanied by marked pigmentary retinopathy and vascular sheathing in the right eye, with only occasional scanty pigment clumping in the left eye. Because her history and clinical findings were not typical for a diagnosis of RP, further medical investigations were carried out, but no systemic cause was identified. The results of an electrodiagnostic test were normal in the left eye but subnormal in the right eye, with nondetectable rod-specific readings, delayed 30-Hz flicker responses, and an absence of the dark trough or light rise on electrooculography. On continued follow-up 9 years later, and after referral to the Birmingham and Midland Eye Centre, she reported a recent-onset progressive visual field defect affecting the left eye and continued problems with photopsia. Visual acuity at this stage was 20/30 and N5 in the right eye and 20/20 and N4.5 in the left. Goldmann visual fields not only showed evidence of severe constriction on the right eye but also demonstrated evidence of left-sided scotoma. Examination revealed mild vitritis affecting each eye, with marked pigmentary changes in the right eye but less marked changes in the left (Figures 1, 2). The optic disk of each eye appeared healthy. Spectral-domain optical coherence tomography (OCT) revealed perifoveal disruption of the photoreceptor inner segment–outer segment junctions of the right eye and scanty intraretinal cystoid spaces at the fovea of the left eye (Figure 3). Because of the ongoing and progressive nature of her symptoms, a number of treatment options were discussed with the patient. This case is presented for comment on diagnosis and management.