title: Binocular Rivalry Measured 2 Hours After Occlusion Therapy Predicts the Recovery Rate of the Amblyopic Eye in Anisometropic Children.
abstract: OBJECTIVE
  Recent studies on adults have shown that short-term monocular deprivation boosts the deprived eye signal in binocular rivalry, reflecting homeostatic plasticity. Here we investigate whether homeostatic plasticity is present also during occlusion therapy for moderate amblyopia.
  
  
  METHODS
  Binocular rivalry and visual acuity (using Snellen charts for children) were measured in 10 children (mean age 6.2 ± 1 years) with moderate anisometropic amblyopia before the beginning of treatment and at four intervals during occlusion therapy (2 hours, 1, 2, and 5 months). Visual stimuli were orthogonal gratings presented dichoptically through ferromagnetic goggles and children reported verbally visual rivalrous perception. Bangerter filters were applied on the spectacle lens over the best eye for occlusion therapy.
  
  
  RESULTS
  Two hours of occlusion therapy increased the nonamblyopic eye predominance over the amblyopic eye compared with pretreatment measurements, consistent with the results in adults. The boost of the nonamblyopic eye was still present after 1 month of treatment, steadily decreasing afterward to reach pretreatment levels after 2 months of continuous occlusion. Across subjects, the increase in nonamblyopic eye predominance observed after 2 hours of occlusion correlated (rho = -0.65, P = 0.04) with the visual acuity improvement of the amblyopic eye measured after 2 months of treatment.
  
  
  CONCLUSIONS
  Homeostatic plasticity operates during occlusion therapy for moderate amblyopia and the increase in nonamblyopic eye dominance observed at the beginning of treatment correlates with the amblyopic eye recovery rate. These results suggest that binocular rivalry might be used to monitor visual cortical plasticity during occlusion therapy, although further investigations on larger clinical populations are needed to validate the predictive power of the technique.
authors.affiliation: Department of Translational Research on New Technologies in Medicine and Surgery University of Pisa, Pisa, Italy 2Institute of Neuroscience, CNR, Pisa, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Lunghi
authors.affiliation: Department of Translational Research on New Technologies in Medicine and Surgery University of Pisa, Pisa, Italy 3Scientific Institute Stella Maris (IRCSS), Calambrone (Pisa), Italy.
authors.forename: Maria Concetta
authors.initials: MC
authors.lastname: Morrone
authors.affiliation: Clinical Ophthalmology Unit, Anna Meyer Children's University Hospital, Florence, Italy.
authors.forename: Jacopo
authors.initials: J
authors.lastname: Secci
authors.affiliation: Clinical Ophthalmology Unit, Anna Meyer Children's University Hospital, Florence, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Caputo
mesh_terms: D000550:Amblyopia / Q000503:physiopathology / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008027:Light; D008297:Male; D009473:Neuronal Plasticity / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D012683:Sensory Deprivation; D060205:Therapeutic Occlusion; D015357:Vision Disparity / Q000502:physiology*; D015348:Vision, Binocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology*