title: Retinal nerve fiber layer thickness in children with optic pathway gliomas.
abstract: OBJECTIVE
  To determine the relationship of high-contrast visual acuity (VA) and low-contrast letter acuity with retinal nerve fiber layer (RNFL) thickness in children with optic pathway gliomas.
  
  
  METHODS
  Cross-sectional convenience sample, with prospective data collection, from a tertiary care children's hospital of patients with optic pathway gliomas associated with neurofibromatosis type 1, sporadic optic pathway gliomas, and neurofibromatosis type 1 without optic pathway gliomas.
  
  
  METHODS
  Patients underwent best-corrected VA testing using surrounded H, O, T, V optotypes and low-contrast letter acuity (5%, 2.5%, and 1.25% low-contrast Sloan letter charts). Mean RNFL thickness (micrometers) was measured by a Stratus optical coherence tomography device (Carl Zeiss Meditec) using the fast RNFL thickness protocol. Eyes were classified as having abnormal vision if they had high-contrast VA of more than 0.1 logarithm of the minimal angle of resolution units or visual field loss. The association of subject age, glioma location, and RNFL thickness with both VA and low-contrast letter acuity scores was evaluated by 1-way analysis of variance and linear regression, using the generalized estimating equation approach to account for within-patient intereye correlations.
  
  
  RESULTS
  Eighty-nine eyes of patients with optic pathway gliomas were included, and 41 were classified as having abnormal VA or visual field loss. Reduced RNFL thickness was associated significantly with higher logarithm of the minimal angle of resolution scores for both VA (P < .001) and all low-contrast letter acuity charts (P < .001) when accounting for age and glioma location.
  
  
  CONCLUSIONS
  Eyes of most children with optic pathway gliomas and decreased RNFL thickness had abnormal VA or visual field loss.
authors.affiliation: Division of Ophthalmology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA. ravery@cnmc.org
authors.forename: Robert A
authors.initials: RA
authors.lastname: Avery
authors.forename: Grant T
authors.initials: GT
authors.lastname: Liu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Fisher
authors.forename: Graham E
authors.initials: GE
authors.lastname: Quinn
authors.forename: Jean B
authors.initials: JB
authors.lastname: Belasco
authors.forename: Peter C
authors.initials: PC
authors.lastname: Phillips
authors.forename: Maureen G
authors.initials: MG
authors.lastname: Maguire
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Balcer
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009412:Nerve Fibers / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000473:pathology; D020339:Optic Nerve Glioma / Q000473:pathology*; D019574:Optic Nerve Neoplasms / Q000473:pathology*; D011446:Prospective Studies; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000175:diagnosis*; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult