Bilateral non-hereditary foveomacular and peripheral retinoschisis in a young female with electrophysiological abnormalities.

PURPOSE: To report a case of non-hereditary bilateral foveomacular and peripheral retinoschisis in a young female, with electrophysiological abnormalities in the absence of high myopia.

METHODS

A 25-year-old female with recent-onset diminution of vision in the left eye (LE) underwent comprehensive ophthalmic evaluation including best-corrected visual acuity (BCVA), slit lamp biomicroscopy, indirect ophthalmoscopy, optical coherence tomography (OCT), full field electroretinography (ERG) and genetic evaluation.

RESULTS

BCVA at presentation was 6/6, N6 in the right eye(RE) and 6/9, N8 in the LE. The patient had a prior history of laser refractive surgery for moderate myopia. Anterior segment examination was unremarkable. Fundus evaluation revealed bilateral foveoschisis and peripheral retinal schisis. OCT showed retinoschisis predominantly involving outer plexiform and outer nuclear layer, along with mild vitreoschisis. Foveal detachment was noted in the LE. ERG demonstrated rod and cone system dysfunction, severe rod bipolar cell dysfunction in both eyes, and a borderline electronegative waveform in the LE. There was no family history, and clinical exome sequencing did not reveal any pathogenic variants associated with the phenotype.

CONCLUSION

Electrophysiological abnormalities with bipolar cell dysfunction, similar to those seen in hereditary retinoschisis, can also occur in non-hereditary retinoschisis. Genetic evaluation is recommended to differentiate between the two, as ERG may show abnormalities in both.