Article

A Binocular Approach to Treating Amblyopia: Antisuppression Therapy

McGill Vision Research, Department of Ophthalmology, McGill University, Montreal, Quebec, Canada.
Optometry and vision science: official publication of the American Academy of Optometry (Impact Factor: 2.04). 09/2010; 87(9):697-704. DOI: 10.1097/OPX.0b013e3181ea18e9
Source: PubMed

ABSTRACT We developed a binocular treatment for amblyopia based on antisuppression therapy.
A novel procedure is outlined for measuring the extent to which the fixing eye suppresses the fellow amblyopic eye. We hypothesize that suppression renders a structurally binocular system, functionally monocular.
We demonstrate using three strabismic amblyopes that information can be combined normally between their eyes under viewing conditions where suppression is reduced. Also, we show that prolonged periods of viewing (under the artificial conditions of stimuli of different contrast in each eye) during which information from the two eyes is combined leads to a strengthening of binocular vision in such cases and eventual combination of binocular information under natural viewing conditions (stimuli of the same contrast in each eye). Concomitant improvement in monocular acuity of the amblyopic eye occurs with this reduction in suppression and strengthening of binocular fusion. Furthermore, in each of the three cases, stereoscopic function is established.
This provides the basis for a new treatment of amblyopia, one that is purely binocular and aimed at reducing suppression as a first step.

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    • "First, the remarkable acquisition of stereopsis by Sue Barry (''Stereo Sue'') in middle-age, documented first by Oliver Sacks (2006) and by Barry (2009) herself, points to the ability of binocular training to either establish, or more likely fine-tune, existing binocular connections that may have been retained despite longstanding alternating strabismus. In addition, remarkable success has been reported in a recent clinical study conducted on three adult strabismic amblyopes from a purely binocular approach to treatment (''antisuppression therapy'') unaccompanied by any patching of the fellow eye (Hess et al., 2010). "
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