Occult macular dystrophy with bilateral chronic subfoveal serous retinal detachment associated with a novel RP1L1 mutation (p.S1199P)

The purpose of this study was to present an atypical case of occult macular dystrophy (OMD) with bilateral chronic subfoveal serous retinal detachment (SRD).

A 53-year-old man was ophthalmologically evaluated because of decreased visual acuity in both eyes. Genomic DNA was extracted from venous blood samples. Mutational analysis of the retinitis pigmentosa 1-like 1 (RP1L1) gene was performed by Sanger sequencing.

Best-corrected visual acuity (BCVA) was 0.1 logMAR in both eyes until the age of 53, after which it gradually declined. Full-field electroretinography (ERG) was unremarkable, while multifocal ERG revealed a reduced central response in both eyes. Optical coherence tomography showed subfoveal SRD in both eyes, and fundus fluorescein angiography yielded unremarkable results. His brother and cousin had similar subjective symptoms. At age 58, his logMAR BCVA was 0.532 (OD) and 0.347 (OS). He was given 23 administrations of intravitreal bevacizumab (IVB; 1.25 mg) in both eyes alternately over a 2-year period and also underwent reduced-fluence photodynamic therapy in both eyes. Two years after the first administration of IVB, a reduction in SRD was obtained, and IVB was therefore discontinued. Three years after the first administration, logMAR BCVA was 0.155 (OD) and 0.523 (OS). Mutational analysis revealed a novel heterozygous missense mutation (p.S1199P).

We describe in detail a case of bilateral chronic subfoveal SRD in an atypical OMD patient carrying a novel heterozygous RP1L1 mutation (p.S1199P). Our results further extend the phenotypic spectrum of RP1L1-associated OMD.