title: Comparison of the Wave Amplitude of Visually Evoked Potential in Amblyopic Eyes between Patients with Esotropia and Anisometropia and a Normal Group.
abstract: BACKGROUND
  We compared the wave amplitude of visually evoked potential (VEP) between patients with esotropic and anisometropic amblyopic eyes and a normal group.
  
  
  METHODS
  The wave amplitude of VEP was documented in 2 groups of persons with amblyopia (15 with esotropia and 28 with anisometropia) and 1 group of individuals with normal visual acuity (n, 15). The amplitude of P100 was recorded monocularly with different spatial frequencies.
  
  
  RESULTS
  Our statistical analysis revealed that the wave amplitude in the 2 groups with amblyopia was significantly decreased compared to that in the normal group (P<0.001). There was a significant difference regarding the amplitude in high spatial frequencies in both high- and low-contrast conditions between the groups with esotropia and anisometropia and the normal group (P<0.001). There were also significant differences in large check-size stimuli and low-contrast condition between the amblyopic groups with esotropia and anisometropia and the normal group (P=0.013 and P=0.044, respectively). In large check-size stimuli and high-contrast condition, a significant difference was indicated only in the comparison between the esotropic amblyopic eyes and the normal eyes (P=0.036).
  
  
  CONCLUSIONS
  The wave amplitude parameter of VEP was influenced by both types of amblyopia, but it seems that this parameter was more sensitive to esotropic amblyopia than anisometropic amblyopia. This outcome may reflect a non-parallel pattern of cortical responses in the comparison of the 2 types of amblyopia with each other and with the control group, which may be beneficial for the diagnosis and treatment of amblyopia.
authors.affiliation: Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Talebnejad
authors.affiliation: Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Optometry, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Saeedeh
authors.initials: S
authors.lastname: Hosseinmenni
authors.affiliation: Department of Optometry, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Jafarzadehpur
authors.affiliation: Department of Optometry, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Mirzajani
authors.affiliation: Department of Optometry, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Enayatollah
authors.initials: E
authors.lastname: Osroosh
keywords: Amblyopia; Anisometropia; Esotropia; Visual evoked potentials