title: Structural and functional measures of inner retinal integrity following visual acuity improvement in a patient with hereditary motor and sensory neuropathy type VI.
abstract: OBJECTIVE
  To report measures of inner retinal integrity following improvement in visual acuity and visual fields in a patient with hereditary motor and sensory neuropathy type VI (HMSN VI).
  
  
  METHODS
  The patient is a Caucasian male with HMSN VI (type 2A Charcot-Marie-Tooth disease and associated optic atrophy) and a c.1090C→T (p.R364W) mutation in the mitofusin 2 (MFN2) gene. The patient's best-corrected visual acuity improved from 20/200 (OD) and 20/400 (OS) at the initial visit to 20/25 in each eye when tested 7 years later. The visual field defects in both eyes that were present at the initial visit were absent at the follow-up visit. The structural integrity of the inner retina was assessed by an evaluation of retinal nerve fiber layer thickness (RNFLT) using optical coherence tomography (OCT), and the functional integrity was assessed by the amplitude of the photopic negative response (PhNR) of the electroretinogram (ERG). At the follow-up visit, the patient's RNFLT was less than the 5th percentile for control subjects in the superior and inferior quadrants OD and in one sector of the temporal quadrant OS, but was within normal limits elsewhere. The PhNR amplitude of each eye was below the lower limit of the normal range.
  
  
  CONCLUSIONS
  The abnormally low PhNR amplitudes and abnormally thin RNFL in certain quadrants of the retina following improvement of visual acuity and visual fields to near-normal values illustrates the potential usefulness of assessing the structure and function of the inner retina in HMSN VI patients.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois 60612, USA. sowjanya@uic.edu
authors.forename: Sowjanya
authors.initials: S
authors.lastname: Gowrisankaran
authors.forename: Anastasios
authors.initials: A
authors.lastname: Anastasakis
authors.forename: Gerald A
authors.initials: GA
authors.lastname: Fishman
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Alexander
mesh_terms: D000328:Adult; D002607:Charcot-Marie-Tooth Disease / Q000235:genetics / Q000503:physiopathology*; D004596:Electroretinography; D020558:GTP Phosphohydrolases; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D024101:Mitochondrial Proteins / Q000235:genetics; D009412:Nerve Fibers / Q000473:pathology*; D017354:Point Mutation; D012164:Retinal Diseases / Q000235:genetics / Q000503:physiopathology*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology
chemical_list: D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D020558:GTP Phosphohydrolases; C470018:MFN2 protein, human