Interventions for stimulus deprivation amblyopia.
BACKGROUND
Stimulus deprivation amblyopia (SDA) develops due to an obstruction to the clear passage of light, preventing clear formation of an image on the retina for example, cataract, ptosis (droopy eyelid). It is particularly severe and can be resistant to treatment and the visual prognosis is often poor. Stimulus deprivation amblyopia is rare and precise estimates of prevalence difficult to come by; it probably constitutes less than 3% of all cases of amblyopia. In developed countries most patients present under the age of one; in less developed parts of the world presentation is likely to be significantly later than this.The mainstay of treatment is patching of the better-seeing eye but regimes vary, treatment is difficult to execute and results are often disappointing.


OBJECTIVE
The objectives of this review were to evaluate the effectiveness of occlusion treatment for SDA, determine the optimum treatment regime and factors that may affect outcome.


METHODS
We searched the Cochrane Central Register of Controlled Trials - CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) on The Cochrane Library (2006, Issue 1), MEDLINE (1996 to April 2006), EMBASE (1980 to April 2006) and LILACS (Latin American and Caribbean Literature on Health Sciences) (to November 2004). There were no date or language restrictions.


METHODS
We aimed to include randomised and quasi-randomised controlled trials of subjects with unilateral SDA defined as worse than 0.2 LogMAR or equivalent. There were no restrictions with respect to age, gender, ethnicity, co-morbidities, medication use, and the number of participants.


METHODS
Two authors independently assessed study abstracts identified by the electronic searches.


RESULTS
No trials were identified that met the inclusion criteria.


CONCLUSIONS
It is not possible to conclude how effective treatment for SDA is or which treatment regime produces the best results. There is a need for further study in this area.
Hatt
S
S
International Centre for Eye Health, c/o Cochrane Eyes and Vision Group, London School of Hygiene & Tropical Medicine, Keppel Street, London, UK WC1E 7HT. sarahrhatt@gmail.com
Antonio-Santos
A
A
Powell
C
C
Vedula
S S
SS
D000550:Amblyopia / Q000209:etiology / Q000628:therapy*; D001763:Blepharoptosis / Q000150:complications; D002386:Cataract / Q000150:complications; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D009779:Occlusive Dressings; D016896:Treatment Outcome