Familial split retinal nerve fiber layer bundles: A case report of two sisters

Split retinal nerve fiber layer (RNFL) bundles are a structural variant of the RNFL, which can be found in healthy eyes. Although the prevalence of split RNFL has been reported to be up to 9.48%, its familial occurrences have yet to be documented. This case report aims to describe two sisters presenting with split RNFL bundles. The first case includes a 22-year-old female with a history of glaucoma suspect. Other than being myopic, she showed no clinical abnormality. Bilateral split RNFL bundles were observed on optical coherence tomography (OCT). The second case describes a 28-year-old female who was the sister of the first case’s patient. Similar to her sister, she also had a normal clinical examination, was myopic, and had split RNFL bundles on OCT. This case report highlights the possibility that the split RNFL bundle phenotype may have a familial nature.