title: Evaluation of visual function and retinal structure in adult amblyopes.
abstract: OBJECTIVE
  To evaluate visual function and its relationship to structure in adult amblyopic subjects.
  
  
  METHODS
  This observational, cross-sectional study included 24 adult amblyopes and 19 healthy subjects. The amblyopes were separated into three groups: anisometropic amblyopes (n = 15), strabismic amblyopes (n = 5), and strabismic amblyopes with anisometropia (n = 4). The relationships of the multifocal visual evoked potential (VEP) results with the clinical findings and psychophysical (Humphrey visual field) and structural (spectral domain optical coherence tomography) diagnostic test data were then investigated.
  
  
  RESULTS
  Significant differences in the multifocal VEP amplitude responses (abnormal cluster defects), combining the interocular and monocular probability analysis, were observed between the anisometropic amblyopic (80%) and nonamblyopic eyes (13.3%) (p < 0.001), whereas in strabismic amblyopia, such defects were found in 100% of the amblyopic and nonamblyopic eyes. Delayed multifocal VEP interocular and monocular latencies were seen in 66.6 and 26.6% of the anisometropic amblyopic and nonamblyopic eyes, with no significant differences between eyes (p = 0.065). Likewise, latency delays were found in 40% of both strabismic amblyopic and nonamblyopic eyes. Multifocal VEP latency showed significant differences between anisometropic and strabismic amblyopic eyes (p = 0.036). Significant agreement was found between the Humphrey visual field and the multifocal VEP visual field defects in the central area of the visual field (p = 0.033). The average retinal nerve fiber layer thickness, foveal and macular thickness, and macular volume, as measured by spectral domain optical coherence tomography, did not show any significant differences between the amblyopic and nonamblyopic eyes and the control group.
  
  
  CONCLUSIONS
  Multifocal VEP amplitudes and latencies were significantly affected in amblyopic eyes and, to a lesser extent, in nonamblyopic eyes. Multifocal VEP response latencies were more delayed in anisometropic eyes than in strabismic eyes, suggesting that anisometropic and strabismic amblyopia may represent different neural abnormalities.
authors.affiliation: *PhD, MD †MD ‡MSc Department of Ophthalmology (CP-R, JG-O, IR-D) and Department of Medicine (JA-S), University Hospital Principe de Asturias, Alcalá de Henares, Madrid, Spain; Department of Ophthalmology, University Hospital General de Guadalajara, Guadalajara, Spain (EG-R); and Department of Physiology (FG) and Department of Surgery (CP-R, RB), University of Alcalá, Madrid, Spain.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Pérez-Rico
authors.forename: Esperanza
authors.initials: E
authors.lastname: García-Romo
authors.forename: Juan
authors.initials: J
authors.lastname: Gros-Otero
authors.forename: Isabel
authors.initials: I
authors.lastname: Roldán-Díaz
authors.forename: Juan
authors.initials: J
authors.lastname: Arévalo-Serrano
authors.forename: Francisco
authors.initials: F
authors.lastname: Germain
authors.forename: Román
authors.initials: R
authors.lastname: Blanco
mesh_terms: D000328:Adult; D000550:Amblyopia / Q000503:physiopathology*; D015858:Anisometropia / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D013285:Strabismus / Q000503:physiopathology; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology*; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult