Unilateral pigmentary retinopathy: a retrospective case series

Abstract

Purpose To review the clinical characteristics and address the aetiology in a group of patients presenting with unilateral retinal pigmentary changes, best described as unilateral pigmentary retinopathy (UPR). Methods The cohort of 42 patients was identified retrospectively from the Moorfields Eye Hospital electrophysiology database. All had undergone full‐field [electroretinography (ERG)] and pattern electroretinography (PERG), with 13 additionally having multifocal ERG (mfERG). The clinical findings, fundus photographs and fundus autofluorescence (AF) images were reviewed. Results All index eyes showed ERG evidence of generalized photoreceptor dysfunction with most showing a similar degree of rod and cone involvement. However, although the fellow eyes all had a normal fundus examination, there were bilateral but asymmetrical ERG abnormalities in eight patients and a further four patients had PERG evidence of macular dysfunction in the fellow eye. A relevant medical history or the diagnosis of an ophthalmologic entity that might be related to the unilateral fundus changes was ascertained in 15 cases (~36%) including acute zonal occult outer retinopathy, trauma, systemic malignancy or autoimmune disease, retinal vasculitis, presumed pregnancy‐related choroidal ischaemia and meningitis. Two patients had a family history of retinitis pigmentosa (RP; 4.8%). Conclusion The underlying aetiology in most cases of UPR cannot accurately be identified, but an heritable cause is unlikely. Aspects of the history clearly suggest an acquired disorder in some patients. Twenty‐five patients (60%) with nongenetic UPR did not adhere to the pattern of rod greater than cone dysfunction that occurs in RP (rod–cone dystrophy), and the pattern of rod > cone dysfunction seen in true RP is thus not a feature of most patients with UPR.

Unilateral Retinitis Pigmentosa Associated with Possible Ciliopathy and a Novel Mutation

“…In patient 2 the ffERG was affected in both eyes, demonstrating a bilateral retinal dystrophy. Similarly, Errera et al reported 42 patients with URP, where eight patients had subnormal ffERG findings in the fellow eye [ 4 ]. The chorioretinal atrophic changes in the peripapillary area along with increased autofluorescence in the right eye of patient 2 might indicate an asymmetric presentation of a bilateral RP.…”

“…Two possible genetic mechanisms have been suggested to play a role in asymmetrical RP or URP, namely, mosaicism and somatic mutations during embryogenesis. However, the exact pathogenesis and genetic mechanism are currently unclear [ 1 , 3 , 4 , 5 ].…”

“…Genetic associations with URP have recently been reported, including mutations in RP1 [ 6 ], RPGR [ 4 ], CLRN1 [ 7 ] and USH2A [ 5 ]. These have only been described in a handful of URP cases.…”

“…These have only been described in a handful of URP cases. Unilateral pigmentary retinopathy (pseudo retinitis pigmentosa) can also arise from a variety of conditions such as ocular trauma, inflammation, retained metallic intraocular foreign body, infections (toxoplasmosis, toxocariasis, syphilis, Lyme disease) and diffuse unilateral subacute neuroretinitis (DUSN), drug toxicity (chloroquine and chlorpromazine), autoimmune retinopathy and cancer-associated retinopathy (CAR) [ 4 ]. Key points that help in the differentiation of URP from common differential diagnoses are summarized in Table 1 .…”

Evaluation of fluocinolone acetonide 0.19 mg intravitreal implant in the management of birdshot retinochoroiditis

“…Pattern ERG P50 was used to assess macular function and darkadapted (DA) and light-adapted (LA) full-field ERGs were used to assess generalised rod and cone system function; the LA 30Hz flicker ERG peak time was examined and plotted separately, as established in previous studies as a sensitive measure of retinal dysfunction in BRC [9,10]. Pattern and full field ERGs obtained before and after treatment were compared and plotted as a percentage of the lower limit of normal, the latter defined as the lowest amplitude in a control group, minus 5% of the reference interval [17]. In all but one case PERG and ERG were performed prior to treatment with Ozurdex ® and/or FAc implant with a mean follow-up of 26 months (median 24.5 months; range 10-54 months).…”