title: Electrophysiological and microperimetry changes in vitamin A deficiency retinopathy.
abstract: OBJECTIVE
  To describe a follow-up case of vitamin A deficiency (VAD)-related retinopathy with macular involvement monitored with electroretinography and microperimetry.
  
  
  METHODS
  Flash (ERG), pattern (PERG), and multifocal (mfERG) electroretinography were recorded in parallel with microperimetry before and during 7-month follow-up of vitamin A treatment on a 65-year-old man presented with a 1-year history of night blindness. The patient had undergone ileostomy procedure for Crohn's disease 14 years ago. His best corrected visual acuity was 6/6 in each eye. Fundus examination revealed macular and mid-peripheral yellow-white lesions compatible with drusen.
  
  
  RESULTS
  Before treatment, PERG was reduced, and mfERG was reduced and delayed, worse in responses from the central rings. These results revealed evidence of bilateral macular and central cone dysfunction. The flash ERG showed reduced dark-adapted 0.01 ERG (rod response); a-wave of dark-adapted 3.0 and 10.0 ERG was normal but b-wave was reduced (negative configuration); light-adapted 3.0 ERG was slightly reduced. The flash ERG revealed evidence of bilateral generalised retinal dysfunction affecting the rod more than cone system. Microperimetry showed deep reduction in retinal sensitivity. Fixation stability was unstable with eccentric locus. During treatment, ERG and microperimetry demonstrated significant improvements. Fixation stability reached normal values after the third treatment week.
  
  
  CONCLUSIONS
  This case illustrates the importance of electrophysiological investigation in early VAD-related retinopathy detection correlated with microperimetry. Our findings indicate a more delayed central cone function recovery than that of generalised rod and cone function. There was a marked correlation between ERG and microperimetric changes.
authors.affiliation: Ophthalmology and Visual Sciences, Division of Clinical Neuroscience, Queen's Medical Centre, University of Nottingham, B Floor, Eye and ENT, Nottingham, NG72UH, UK.
authors.forename: Saker
authors.initials: S
authors.lastname: Saker
authors.forename: Marco
authors.initials: M
authors.lastname: Morales
authors.forename: Harsimar
authors.initials: H
authors.lastname: Jhittay
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Wen
authors.forename: Winfried
authors.initials: W
authors.lastname: Amoaku
mesh_terms: D000284:Administration, Oral; D000368:Aged; D003424:Crohn Disease / Q000601:surgery; D003623:Dark Adaptation; D004596:Electroretinography / Q000379:methods*; D006801:Humans; D007081:Ileostomy; D007273:Injections, Intramuscular; D008297:Male; D009755:Night Blindness / Q000188:drug therapy / Q000503:physiopathology*; D010775:Photic Stimulation; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology; D012160:Retina / Q000503:physiopathology*; D012164:Retinal Diseases / Q000188:drug therapy / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields / Q000502:physiology; D014801:Vitamin A / Q000627:therapeutic use; D014802:Vitamin A Deficiency / Q000188:drug therapy / Q000503:physiopathology*; D014815:Vitamins / Q000627:therapeutic use
chemical_list: D014815:Vitamins; D014801:Vitamin A