This patient was a 33-year-old male under systemic corticosteroids and methotrexate treatment for serpiginous choroidopathy presented for a transition of care. Best corrected visual acuitities were 20/20 in the right eye and 20/25 in the left eye. Intraocular pressures were 18/15 mmHg for the right and left eyes with topical dorzolamide and timolol treatment. Slit-lamp examinations revealed posterior subcapsular cataracts in both eyes.
Dilated fundus examinations of both eyes showed bilateral symmetrical bone spicule-like pigmentation and retinochoroidal atrophy along the retinal veins.
Fundus autofluorescence revealed that both pigmented and atrophic areas appeared hypoautofluorescent, while the borders of the chorioretinal atrophy exhibited hyperautofluorescence. The hyperautofluorescent rim surrounding the hypoautofluorescent atrophy is thought to represent a hyperfunctional retinal pigment epithelium with lipofuscin accumulation, indicating a transition zone between healthy and degenerating retina.
Horizontal and vertical optical coherence tomography scans exhibited atrophy of the outer retinal layers and retinal pigment epithelium in the paravenous areas with a normal foveal contour.
Differential diagnosis is guided by clinical evaluation and multimodal imaging findings. The case exhibit regions of retinochoroidal atrophy tracing retinal veins with pigment accumulation varying from fine scattered deposits to pigment clumping and more severe bone spicule-like pigmentation. Paravenous lesion distribution is a hallmark of pigmented paravenous retinochoroidal atrophy, distinguishing it from phenotypically similar entities such as pericentral retinitis pigmentosa and serpiginous choroidopathy, which typically involve extraparavenous areas.
Pigmented paravenous retinochoroidal atrophy is characterized by perivenous aggregations of pigment clumps associated with peripapillary and radial zones of retinochoroidal atrophy which are distributed along the retinal veins. Patients are often asymptomatic and diagnosis is made with clinically by characteristic fundus appearance. It is usually asymptomatic and often diagnosed fortuitously during routine fundus examination, since the disease tends to be non-progressive or slowly progressive. The cause of pigmented paravenous retinochoroidal atrophy remains unknown, but there are several hypotheses on whether this has a dysgenetic, degenerative, hereditary etiology or even an inflammatory cause.
Credit: Kemal Tekin, M.D., from Ulucanlar Eye Training and Research Hospital
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