2020–2021 BCSC Basic and Clinical Science Course™
6 Pediatric Ophthalmology and Strabismus
Part II: Pediatric Ophthalmology
Chapter 26: Optic Disc Abnormalities
Developmental Anomalies
Myelinated Retinal Nerve Fiber Layer
Myelination of the optic nerve normally stops at the lamina cribrosa. Inappropriate myelination anterior to the lamina cribrosa causes scotomata or central vision loss. Particularly when the macula is involved, myelinated retinal nerve fibers are associated with ipsilateral high myopia and resultant anisometropic amblyopia. In some cases, the macula is hypoplastic.
Clinically, myelinated nerve fibers appear as a white superficial retinal area, the frayed and feathered edges of which tend to follow the same orientation as that of the normal retinal nerve fibers (Fig 26-7). Retinal vessels that pass within the superficial layer of the nerve fibers are obscured. The myelinated fibers may occur as a single spot or as several noncontiguous patches. The most common location is along the disc margin.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.