Binocular treatment in adult amblyopia is based on parvocellular or magnocellular pathway

Eur J Ophthalmol. 2020 Jul;30(4):658-667. doi: 10.1177/1120672119841216. Epub 2019 Apr 24.

Abstract

Introduction: Amblyopia is speculated to be an untreatable disease in the patient, who is beyond the critical period of vision; however, currently, it is treatable in adults.

Purpose: This study aimed to elucidate whether the treatment is useful in both anisometropic amblyopia and strabismic amblyopia. In addition, the differences were detected between anisometropic amblyopia and strabismic amblyopia after the same perceptual treatment and whether the suppression in anisometropic amblyopia or strabismic amblyopia could be decreased before and after the treatment.

Methods: A binocular perceptual learning was applied for the treatment, the suppression was measured, and the patients were followed up for 2 months after training. Anisometropic amblyopia and strabismic amblyopia groups were subjected to the assessment of stereo, visual acuity, contrast sensitivity, and suppression before and after the training.

Results: After 6 weeks of "Diploma Gabor Orientation Coherence" training, in the anisometropic amblyopia group, the outcomes of visual acuity (t = 3.114, p = 0.026) and contrast sensitivity (t = 7.786, p = 0.001) were increased significantly. While in the strabismic amblyopia group, the outcomes of stereo (t = 2.987, p = 0.040) and contrast sensitivity (t = 3.638, p = 0.022) were increased significantly.

Conclusion: After Diploma Gabor Orientation Coherence training in the same frequency and in the same duration, the anisometropic amblyopia group got an improvement in visual acuity, but the strabismic amblyopia group got an improvement in stereo. As there are evidences to show that anisometropic amblyopia and strabismic amblyopia were injured in different pathways, we think the diverse results might come from the different pathway injury in anisometropic amblyopia and strabismic amblyopia.

Keywords: Adult amblyopia; binocular perceptual learning treatment; coherence threshold; magnocellular; parvocellular; suppression.

MeSH terms

  • Adult
  • Amblyopia / physiopathology
  • Amblyopia / therapy*
  • Anisometropia / physiopathology
  • Anisometropia / therapy*
  • Contrast Sensitivity / physiology
  • Depth Perception / physiology
  • Discrimination Learning / physiology*
  • Female
  • Humans
  • Male
  • Strabismus / physiopathology
  • Strabismus / therapy*
  • Vision, Binocular / physiology*
  • Visual Acuity / physiology
  • Visual Perception / physiology*
  • Young Adult