OBJECTIVE To evaluate the effectiveness of treatment of amblyopia in children aged 7 to 17 years. METHODS At 49 clinical sites, 507 patients with amblyopic eye visual acuity ranging from 20/40 to 20/400 were provided with optimal optical correction and then randomized to a treatment group (2-6 hours per day of prescribed patching combined with near visual activities for all patients plus atropine sulfate for children aged 7 to 12 years) or an optical correction group (optical correction alone). Patients whose amblyopic eye acuity improved 10 or more letters (> or =2 lines) by 24 weeks were considered responders. RESULTS In the 7- to 12-year-olds (n = 404), 53% of the treatment group were responders compared with 25% of the optical correction group (P<.001). In the 13- to 17-year-olds (n = 103), the responder rates were 25% and 23%, respectively, overall (adjusted P = .22) but 47% and 20%, respectively, among patients not previously treated with patching and/or atropine for amblyopia (adjusted P = .03). Most patients, including responders, were left with a residual visual acuity deficit. CONCLUSIONS Amblyopia improves with optical correction alone in about one fourth of patients aged 7 to 17 years, although most patients who are initially treated with optical correction alone will require additional treatment for amblyopia. For patients aged 7 to 12 years, prescribing 2 to 6 hours per day of patching with near visual activities and atropine can improve visual acuity even if the amblyopia has been previously treated. For patients 13 to 17 years, prescribing patching 2 to 6 hours per day with near visual activities may improve visual acuity when amblyopia has not been previously treated but appears to be of little benefit if amblyopia was previously treated with patching. We do not yet know whether visual acuity improvement will be sustained once treatment is discontinued; therefore, conclusions regarding the long-term benefit of treatment and the development of treatment recommendations for amblyopia in children 7 years and older await the results of a follow-up study we are conducting on the patients who responded to treatment.

/pdf/randomized-trial-of-treatment-of-amblyopia-in-children-aged-1fgop9k9yu.pdf

Randomized trial of treatment of amblyopia in children aged 7 to 17 years.

Prevalence of Amblyopia and Strabismus in White and African American Children Aged 6 through 71 Months: The Baltimore Pediatric Eye Disease Study

Amblyopia and binocular vision.

https://www.acotv.org/media/com_lazypdf/pdf/perceptual_learning_as_a_potential_treatment_for_amblyopia_a_mini-review.pdf

Perceptual learning as a potential treatment for amblyopia: A mini-review

Amblyopia characterization, treatment, and prophylaxis.

METHODS. The study comprised three distinct phases: baseline, in which repeat measures of visual function were undertaken to confirm the initial visual deficit; refractive adaptation: an 18-week period of spectacle wear with six weekly measurements of logarithm of the minimum angle of resolution (logMAR) visual acuity; occlusion: in which participants were prescribed 6 hours of “patching” per day. In the latter phase, occlusion was objectively monitored and logMAR visual acuity recorded at 2-week intervals until any observed gains had ceased. RESULTS. Data were obtained from 94 participants (mean age, 5.1 1.4 years) with amblyopia associated with strabismus (n 34), anisometropia (n 23), and both anisometropia and strabismus (n 37). Eighty-six underwent refractive adaptation. Average concordance with patching was 48%. The relationship between logMAR visual acuity gain and total occlusion dose was monotonic and linear. Increasing dose rate beyond 2 h/d hastened the response but did not improve outcome. More than 80% of the improvement during occlusion occurred within 6 weeks. Treatment outcome was significantly better for children younger than 4 years (n 17) than in those older than 6 years (n 24; P 0.0014). CONCLUSIONS. Continuous objective monitoring of the amount of patching therapy received has provided insight into the dose–response relationship of occlusion therapy for amblyopia. Patching is most effective within the first few weeks of treatment, even for those in receipt of a relatively small dose. Further studies are needed to elucidate the neural basis for the dose–response functions. (Invest Ophthalmol Vis Sci. 2004;45: 3048 –3054) DOI:10.1167/iovs.04-0250

Treatment dose-response in amblyopia therapy: the Monitored Occlusion Treatment of Amblyopia Study (MOTAS).

Aim: To describe the visual response to spectacle correction (“refractive adaptation”) for children with unilateral amblyopia as a function of age, type of amblyopia, and category of refractive error. Method: Measurement of corrected amblyopic and fellow eye logMAR visual acuity in newly diagnosed children. Measurements repeated at 6 weekly intervals for a total 18 weeks. Results: Data were collected from 65 children of mean (SD) age 5.1 (1.4) years with previously untreated amblyopia and significant refractive error. Amblyopia was associated with anisometropia in 18 (5.5 (1.4) years), strabismus in 16 (4.2 (0.98) years), and mixed in 31 (5.2 (1.5) years) of the study participants. Mean (SD) corrected visual acuity of amblyopic eyes improved significantly (p Conclusion: Refractive adaptation is a distinct component of amblyopia treatment. To appropriately evaluate mainstream therapies such as occlusion and penalisation, the beneficial effects of refractive adaptation need to be fully differentiated. A consequence for clinical practice is that children may start occlusion with improved visual acuity, possibly enhancing compliance, and in some cases unnecessary patching will be avoided.

https://bjo.bmj.com/content/bjophthalmol/88/12/1552.full.pdf

Refractive adaptation in amblyopia: quantification of effect and implications for practice.

PURPOSE To identify factors that influence the outcome of treatment for unilateral amblyopia, as a part of the Monitored Occlusion Treatment of Amblyopia Study (MOTAS). METHODS This was an intervention study consisting of three nonoverlapping phases: "Baseline", "refractive adaptation" (18 weeks of full-time spectacle wear), and "occlusion" (6 hours of patching per day, objectively monitored). Condition factors: type of amblyopia, age of participant, initial severity of amblyopia, fixation, and binocular vision status; treatment factors: refractive adaptation and occlusion (total dose [hours] and dose rate [hours per day]) were assessed for their influence on visual outcome. Visual outcome was expressed in three ways: logMAR (logarithm of the minimum angle of resolution) change, residual amblyopia, and proportion of the deficit corrected. RESULTS The study included 85 participants (mean age, 5.1 +/- 1.4 years) with amblyopia associated with strabismus (n = 32) or anisometropia (n = 20) or associated with both anisometropia and strabismus (n = 33). Treatment factors: cumulative occlusion dose exceeding 50 hours, and dose rates > or =1 hour per day resulted in (P < or = 0.01) lower residual amblyopia and a greater proportion of the deficit corrected. Condition factors associated with poor outcome (high residual amblyopia) were presence of eccentric fixation, severe initial amblyopia, and no binocular vision. CONCLUSIONS Factors influencing outcome with treatment for amblyopia are occlusion dose (the rate of delivery and cumulative dose worn), the initial severity of the amblyopia, binocular vision status, fixation of the amblyopic eye, and the age of the subject at the start of treatment.

Treatment of unilateral amblyopia: factors influencing visual outcome.

Background/aims: The effectiveness of occlusion therapy for the treatment of amblyopia is a research priority. The authors describe the design of the Monitored Occlusion Treatment for Amblyopia Study (MOTAS) and its methodology. MOTAS will determine the dose-response relation for occlusion therapy as a function of age and category of amblyopia.

Methods: Subjects progress through up to three study phases: (1) Assessment and baseline phase: On confirmation of eligibility, and after parental consent, baseline visual functions are determined, and spectacles prescribed as necessary; (2) Refractive adaptation phase: Subjects wear spectacles full time and return to clinic at 6 weekly intervals until 18 weeks, by which time all improvement due to refractive correction is complete; (3) Occlusion phase: All subjects are prescribed 6 hours of occlusion per day. Daily occlusion is objectively monitored using an occlusion dose monitor (ODM). Outcome variables: visual acuity (logMAR charts), log contrast sensitivity (Pelli-Robson chart), and stereoacuity (Frisby) are assessed at 2 weekly intervals until gains in visual acuity cease to be statistically verifiable.

Conclusion: Four methodological issues have been addressed; firstly, baseline stability of visual function; secondly, differentiation of refractive adaptation from occlusion; thirdly, objective measurement of occlusion dose and concordance; fourthly, use of validated outcome measures.

https://bjo.bmj.com/content/bjophthalmol/86/8/915.full.pdf

M J Moseley

Papers

Treatment dose-response in amblyopia therapy: the Monitored Occlusion Treatment of Amblyopia Study (MOTAS).

Refractive adaptation in amblyopia: quantification of effect and implications for practice.

Treatment of unilateral amblyopia: factors influencing visual outcome.

Design of the Monitored Occlusion Treatment of Amblyopia Study (MOTAS).

Optimization of the Dose–Response of Occlusion Therapy for Amblyopia: the ROTAS study