Risk factors for treatment failure of anisometropic amblyopia.
OBJECTIVE
This study sought to explore factors which might predict the lack of vision improvement following therapy of anisometropic amblyopia.


METHODS
We retrospectively reviewed the records of 104 children aged 3 to 8 years who had anisometropic amblyopia with a difference in the refractive power between the two eyes of at least 1 diopter, a difference in corrected visual acuity between the two eyes of at least 3 logMAR units, visual acuity in the amblyopic eye of 20/50 or worse, and no ocular structural abnormalities. Patients were treated with either patching or atropine penalization therapy. Patients with strabismus were included. Treatment failure was defined in two ways: (1) functional failure indicating a final visual acuity in the amblyopic eye worse than 20/40 and (2) relative failure indicating less than three lines of logMAR visual acuity improvement regardless of final vision.


RESULTS
Failure risk factors were as follows: age above 6 at the onset of treatment (adjusted odds ratio [OR] (95% confidence limits [CL] = 4.69 [1.55, 14.2]), the presence astigmatism of more than 1.50 diopters in the amblyopic eye (adjusted [OR] (95% CL) = 5.78 [1.27, 26.5]), poor compliance with treatment (adjusted [OR] (95% CL) = 5.47 [1.70, 17.6]), and initial visual acuity in the amblyopic eye of 20/200 or worse (adjusted [OR] (95% CL) = 3.79 [1.28, 11.2]). Strabismus was not found to be a significant risk factor. Neither the type or amount of refractive error nor the difference in the refractive power between the two eyes was a significant risk factor for treatment failure.


CONCLUSIONS
Eyes with poor initial visual acuity, the presence of significant astigmatism, and age over 6 years were less likely to achieve successful outcome. The clinical profile of patients with anisometropic amblyopia may be useful in predicting response to therapy, but compliance with treatment has a major effect on response to therapy.
Hussein
Mohamed A W
MA
Cullen Eye Institute, Baylor College of Medicine, Department of Ophthalmology, Texas Children's Hospital, Houston 77030, USA.
Coats
David K
DK
Muthialu
Arpitha
A
Cohen
Ethan
E
Paysse
Evelyn A
EA
D000367:Age Factors; D000550:Amblyopia / Q000628:therapy*; D015858:Anisometropia / Q000628:therapy*; D001251:Astigmatism / Q000150:complications; D001285:Atropine / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009184:Mydriatics / Q000627:therapeutic use; D010349:Patient Compliance; D012189:Retrospective Studies; D012307:Risk Factors; D012683:Sensory Deprivation; D013285:Strabismus / Q000150:complications; D017211:Treatment Failure; D014792:Visual Acuity
D009184:Mydriatics; D001285:Atropine