Peripheral retinal nerve fiber myelination

Abstract

Retinal nerve fiber myelination is a benign condition, rare and asymptomatic in most cases¹. The optic nerve myelination process in normal development is carried out by oligodendrocytes, which begins in the fifth week of gestation at the level of the lateral geniculate body, stopping at the lamina cribrosa in week 37^1,2. Although its pathophysiology is not clear, it is believed that the neurohumoral mechanisms that stop the process at that level fail, so the most frequent location is peripapillary¹. This condition is present from birth and is usually an incidental finding in the fundus². The impairment of visual function is highly variable according to the location of the affected area, as it blocks light transmission to the photoreceptors, reducing retinal sensitivity, which may affect the visual field². It can also be observed with other pathologies such as myopia, strabismus or amblyopia³.

We present a clinical case of an adult patient, 40 years old, hospitalized for sepsis, without ophthalmologic manifestations. In the ophthalmologic examination, visual acuity was preserved, and in the fundus fundus myelination of the retinal nerve fibers was observed, with pearly color and feathery appearance, located in the periphery of both eyes, as a casual finding. This involvement of the nerve fibers did not cause alterations in the visual field.