Patching, atropine may suit moderate or severe amblyopia

Dr. Hug reviewed the findings from the Amblyopia Treatment Studies (ATS) undertaken by the Pediatric Eye Disease Investigator Group (PEDIG), and discussed application of the results into clinical practice.

The ATS consisted of a series of prospective, multicenter, controlled clinical trials investigating the efficacy and safety of different patching and atropine regimens for the management of amblyopia in children aged 3 to 7 years.

Treatment protocols

In the trial comparing atropine 1% daily with 6 hours of patching for moderate amblyopia, children were treated for 6 months. In all other trials, treatment duration was 4 months.

Each treatment protocols included 1 hour of near work daily; another PEDIG study investigated whether or not there was a benefit of near activity.

In the trial of severe amblyopia treatment, full-time patching and 6 hours of patching were associated with similar VA improvement in the amblyopic eye at both 5 weeks and study conclusion. However, 10% of patients in the full-time occlusion group were able to stop patching at 5 weeks because they had achieved equal acuity in both eyes, compared with only 1% of children in the part-time occlusion group.

"That 10% response rate at 5 weeks is huge considering these were severe amblyopes," said Dr. Hug, associate professor, Children's Mercy Hospitals and Clinics, Kansas City, MO. "The ability to be done with the patching after just 5 weeks can be a big deal for parents and patients."

Analyses of treatment groups

An analyses of occlusion strabismus showed that the rate was similar in both treatment groups (approximately 8%).

The incidence of occlusion amblyopia was slightly higher in children who wore the patch all day, compared with those having part-time occlusion (11% versus 6%, respectively). In all patients but one, VA returned to 20/20 when occlusion stopped.

Results from the studies of moderate amblyopia treatment showed VA improvement was similar whether patients used a 2- or 6-hour patching regimen. The same was true in comparisons of 6 hours of patching or daily atropine. Outcomes were also similar whether atropine was instilled daily or just on the weekend.