title: A morphological study of amblyopic eyes in children failing to achieve normal visual acuity after electronically monitored long-term occlusion treatment.
abstract: OBJECTIVE
  To search for morphological abnormalities in compliant unilaterally amblyopic children with poor occlusion treatment outcomes, for the first time with electronically recorded patching dosage. We included school children with remaining interocular logMAR (logarithm of the minimum angle of resolution) difference ≥ 0.3 after patching time of more than 22 months and 1300 h total in a previous prospective study.
  
  
  METHODS
  Six patients with a mean age of 11.19 years were included. Four patients had anisometropic amblyopia and two patients had a mixed strabismic and anisometropic amblyopia. Best-corrected visual acuity, cycloplegic refraction, dilated fundus examination, optic disc morphology and macular thickness using optical coherence tomography (OCT), retinal visual acuity, color perception, and the presence of a relative afferent pupillary defect (RAPD) were assessed. Paired t tests were performed to compare optic disc values and macular thickness of the amblyopic eyes to those of the fellow eyes.
  
  
  RESULTS
  Average (± SD) logMAR VA in the amblyopic eyes was 0.42 (±0.23) with a remaining average interocular difference (IOD) of 0.51 (± 0.23), despite electronically monitored occlusion treatment of more than 1300 h. All patients presented with hyperopia and a significantly different mean spherical equivalent of + 4.73 (± 2.73) D in the amblyopic eye compared with the fellow eye (p = 0.02). A statistically significant difference in macular thickness was found between amblyopic and fellow eyes, with amblyopic eyes having an increased average thickness (p = 0.0062) and total volume (p = 0.0091) of the macula. One patient had familial hereditary primary macrodisc in both eyes.
  
  
  CONCLUSIONS
  Our results provide evidence that average macular thickness and total macular volume tended to be increased among these compliant amblyopic children with unsatisfactory occlusion treatment outcomes. Further studies are warranted to evaluate whether morphological changes may have an impact on the effectiveness of amblyopia treatment. Moreover, our findings suggest that greater magnitude of hyperopia and anisometropia as well as older age may be risk factors associated with a poor visual acuity outcome among compliant amblyopic children.
authors.affiliation: Department of Ophthalmology, Goethe-University, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany. hattenbach@med.uni-frankfurt.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Kuhli-Hattenbach
authors.affiliation: Department of Ophthalmology, Goethe-University, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany.
authors.forename: Michael Janusz
authors.initials: MJ
authors.lastname: Koss
authors.affiliation: Department of Ophthalmology, Goethe-University, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kohnen
authors.affiliation: Department of Ophthalmology, Goethe-University, Theodor-Stern-Kai 7, 60590, Frankfurt am Main, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Fronius
mesh_terms: D000550:Amblyopia / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D015858:Anisometropia / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D001458:Bandages; D002648:Child; D002675:Child, Preschool; D003118:Color Perception / Q000502:physiology; D005260:Female; D006801:Humans; D007223:Infant; D008266:Macula Lutea / Q000473:pathology*; D008297:Male; D018670:Monitoring, Ambulatory; D010349:Patient Compliance; D012029:Refraction, Ocular / Q000502:physiology; D012683:Sensory Deprivation; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D014792:Visual Acuity / Q000502:physiology*
keywords: Amblyopia; Anisometropia; Macular thickness; Occlusion dose monitor (ODM); Occlusion treatment; Optical coherence tomography (OCT)