Polarimetric nerve fiber analysis in patients with peripapillary myelinated retinal nerve fibers

Abstract

ABSTRACT.Purpose: The aim of this study was to compare the RNFL thickness in eyes with myelinated retinal nerve fibers (MRNF) and age, sex-matched controls using scanning laser polarimetry. Methods: Seventeen patients with MRNF underwent a comprehensive ophthalmological examination including automated visual field testing, and scanning laser polarimetry with Nerve Fiber Analyser (NFA II). Twenty eyes with MRNF from 17 patients were available for the study. Sixteen healthy, age and sex-matched subjects were taken as controls. Retinal nerve fiber thickness measurements of the four sectors (superior, inferior, nasal, temporal) and along the whole circumference of the optic disc were obtained for affected and control eyes, and compared. Results: Inferior average and inferior integral parameters of the NFA revealed significantly thinner RNFL thickness measurements in eyes with inferiorly located MRNF compared to controls. Conclusion: Retinal myelination alters the birefringent property of the RNFL, and results in diminished thickness measurements. Hence, NFA measurements in patients with MRNF may not be reliable.Key words: myelinated retinal nerve fibers -nerve fiber analysis -scanning laser polarimetryvisual field defect.