Abstract
Purpose: :
To survey the clinical characteristics of patients with unilateral pigmented retinopathy.
Methods: :
Thirty seven patients were ascertained retrospectively following pattern and full field electroretinography (PERG;ERG) that incorporated the International standards. Clinical findings, fundus photographs and fundus autofuorescence were reviewed.
Results: :
Of 37 patients, 29 women and 8 men between 13 and 67 years of age were ascertained. Associated conditions, that may explain aetiology were noted in 13 cases (35%) and included direct ocular trauma, prior ocular inflammation, systemic carcinoma, pregnancy induced hypotension and meningitis. An inherited disorder was definitely identified in 2 patients; one had a RP1 germline mutation and dominant family history and one was a female carrier of X-linked RP. Peripheral field loss and photopsias were common symptoms. Some were asymptomatic and were found to have UPR as part of a routine spectacle check-up. Reduced visual acuity was a later feature of the disorder. Fundoscopy revealed a range of abnormalities and varying degrees of intraretinal pigmentary deposition with 12.5% of patient not having frank bone-spicule pigmentation. Two patients had cystoid macular oedema (5%). On electrophysiologic findings, all patients presented a generalised loss of retinal function affecting both rod and cone systems and a dysfunction at the level of the retinal pigment epithelium/ photoreceptor complex. Pattern ERG was abnormal in 29 patients (78.4%) indicating macular involvement. There was subclinical involvement in the better seeing eye in 6 cases (16%) as assessed by electrophysiology with borderline or marginally subnormal full field ERGs, multifocal ERG and fundus autofluorescence imaging.
Conclusions: :
True unilateral RP is an uncommon cause of unilateral pigmentary retinopathy. Post traumatic and post-inflammatory disorders are more common, but the aetiology of most cases is unknown. Nevertheless, mosaisism for a mutant gene during development cannot be excluded.
Keywords: retina • electrophysiology: clinical • retinal degenerations: hereditary