Persistent Diffuse Photoreceptor Disorganization

Purpose: To characterize persistent diffuse photoreceptor disorganization (PDPD), a newly recognized retinal disorder, and establish diagnostic criteria differentiating it from similar outer retinopathies. Methods: This retrospective observational case series included 14 patients (21 eyes) with subacute vision loss, unremarkable fundus, and persistent diffuse photoreceptor disorganization on OCT, from 2020 to 2025. Medical records, multimodal imaging (OCT, fundus autofluorescence [FAF], fluorescein angiography [FA], indocyanine green angiography [ICGA]), and visual function (electroretinography [ERG], visual field) findings were analyzed. Results: Patients (mean age 30.7 years) presented with subacute vision loss [mean BCVA 0.9 LogMAR (20/160), range, 2.0-0.2 (FC-20/32)]. Seven patients (50%) had bilateral involvement. Infectious uveitis and known retinal dystrophy mutations (via whole-exome sequencing) were excluded. Fundus, FAF, and ICGA were largely unremarkable. OCT revealed blurred/rough ellipsoid zone and absent interdigitation zone in the posterior pole of all eyes (including fovea in 100% of cases, periphery in 92.9%). The RPE layer was preserved. Outer retina thickness was significantly thinner in involved eyes compared to fellow eyes (118.3 vs. 147.6 µm, p=0.031). FA showed peripheral venous leakage in 75% of eyes. Full-field ERG indicated reduced amplitudes (normal latency, scotopic/photopic), and visual fields showed significant defects. Eleven patients received immunosuppressive therapies. Over 17 months, OCT abnormalities persisted, outer retina thickness slowly decreased, and visual acuity remained stable with gradual deteriorations in some patients. Conclusions: PDPD is characterized by subacute, diffuse, and persistent photoreceptor disorganization with largely unremarkable fundus, distinct from other outer retinopathies. Visual prognosis is generally poor, necessitating further research into pathogenesis and treatment. Key words: photoreceptor disorganization; ellipsoid zone; interdigitation zone; OCT