title: A comparative study of visual evoked potentials in optic neuritis and optic neuritis with multiple sclerosis.
abstract: OBJECTIVE
  To compare the visual evoked potentials (VEP) in patients with acute optic neuritis, recurrent optic neuritis, and optic neuritis with multiple sclerosis.
  
  
  METHODS
  The authors retrospectively reviewed VEP latency records of the patients with optic neuritis in Siriraj Hospital from 1995 to 2005 and divided them into three groups, acute optic neuritis, recurrent optic neuritis, and optic neuritis with multiple sclerosis (ON/MS). The patients with non-recordable VEP in the analysis were excluded. Comparison of the mean latency of the VEP in affected eyes among the three groups was statistically analyzed by a nonparametric independent sample test.
  
  
  RESULTS
  Twenty-two patients with acute optic neuritis, 8 patients with recurrent optic neuritis, and 22 patients with ON/MS participated in this study. The mean age among the three groups was not statistically significant. The median value of the latency of flash VEP (fVEP) and pattern reversal VEP (PRVEP) in the acute optic neuritis group was shorter than that of the recurrent optic neuritis group, and statistically significant (fVEP p = 0.012; PRVEP, p = 0.004). The median value of the latency of PRVEP in the acute optic neuritis group was shorter than that of the ON/MS group, and statistically significant (PRVEP p = 0.002). The median value of the latency of both fVEP and PRVEP in the recurrent optic neuritis group and ON/MS group were delayed with no statistical significance (fVEP p = 0.458; PRVEP, p = 0.403).
  
  
  CONCLUSIONS
  The VEP can be used to demonstrate the demyelinating mechanism of optic neuritis and optic neuritis with multiple sclerosis, but cannot determine the susceptibility of the patients with acute ON to become MS. The significantly delayed latency of VEP in recurrent optic neuritis is possibly caused by severe damage of the optic nerve conduction from recurrent attacks.
authors: Department of Ophthalmology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkoknoi, Bangkok, Thailand.
authors: Pathanee
authors: P
authors: Samsen
authors: Wanicha L
authors: WL
authors: Chuenkongkaew
authors: Patcharapim
authors: P
authors: Masayaanon
authors: Niphon
authors: N
authors: Chirapapaisan
authors: Ngamkae
authors: N
authors: Ruangvaravate
authors: Siriwan
authors: S
authors: Loket
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000503:physiopathology*; D009902:Optic Neuritis / Q000503:physiopathology*; D012008:Recurrence; D012189:Retrospective Studies; D013997:Time Factors