title: [A study of multi-channel visual evoked potentials in exotropic children without amblyopia].
abstract: OBJECTIVE
  To investigate the clinical significance of multi-channel visual evoked potentials (VEPs) in constant exotropic children without amblyopia and the mechanism of exotropia.
  
  
  METHODS
  With 14 active cup electrodes, and full and half field stimulation, the checkerboard pattern was reversed and the VEPs were recorded in control and experimental groups.
  
  
  RESULTS
  With full field stimulation, the latent period 1 (LP1) of binocular VEPs was not longer and the amplitude N1-P1 (AN1P1) not higher respectively than those of monocular VEPs in experimental group. These properties were different from those of control group. The AN1P1 of non-dominant eye was decreased, and the LP1 of dominant and non-dominant eye was longer in experimental group than that of the control group. There were no significant differences in comparing LP1 and AN1P1 between nasal-retina and temporal-retina of experimental group.
  
  
  CONCLUSIONS
  VEPs can provide a scientific basis for abnormal binocular vision in constant exotropia. Although the visual acuity of constant exotropic children is normal, their VEPs are abnormal. Therefore, there might be dysfunction in primary visual cortex. With half field stimulation, there is no suppression of temporal-retina in monocular VEPs of constant exotropic children.
authors.affiliation: Department of Pediatric Ophthalmology, First School of Clinical Medicine, Beijing Medical University.
authors.forename: X
authors.initials: X
authors.lastname: Chen
authors.forename: J
authors.initials: J
authors.lastname: Guo
authors.forename: H
authors.initials: H
authors.lastname: Cai
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005074:Evoked Potentials, Visual; D005099:Exotropia / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male