Older Children May Benefit From Treatment for Lazy Eye
Some children aged seven to 17 who had previously been thought too old to benefit from treatment for amblyopia, commonly known as ''lazy eye'', showed improvement after treatment in a clinical trial reported in the April issue of Archives of Ophthalmology, one of the JAMA/Archives journals.
Although it is widely agreed that amblyopia, a condition that involves poor vision and/or poor muscle control of one eye, can be effectively treated in children younger than six, it has generally been believed that older children were unlikely to benefit from treatment, according to background information in the article. The upper limit for successful treatment response has been believed to be six to seven or nine to ten years of age. The current study is designed to evaluate the effectiveness of treatment of amblyopia in children aged seven to 17 years.
Mitchell M. Scheiman, O.D., Richard W. Hertle, M.D., and colleagues in the Pediatric Eye Disease Investigator Group (PEDIG), conducted a randomized treatment trial of 507 older children with amblyopia at 49 clinical sites. All the patients were provided with optimal optical correction (children who already had glasses were given new ones). Children were then randomly assigned to receive treatment for amblyopia or to receive optical correction alone. Children aged seven to 12 in the treatment group were treated with two to six hours a day of patching over the sound eye combined with near visual activities such as playing with a GameBoy, homework, or reading, and one drop daily of atropine for the sound eye. Patients in the older treatment group (aged 13 to 17 years) were treated with patching and near visual activities alone.
Follow up visits occurred every six weeks for up to 24 weeks until the patients were classified as a responder or non-responder. A patient in the study was classified as a responder if the amblyopic eye acuity (sharpness of vision) was 10 or more letters (two lines on the eye chart) better than baseline. A patient was classified as a non-responder if amblyopic eye acuity had not improved 10 or more letters by the 24th week or if there was no improvement at all from a prior follow-up visit (or baseline).
Of the 404 seven- to 12-year-olds in the study, 53 percent (106 of 201) in the treatment group were responders compared with 25 percent in the optical correction group. Of the 13- to 17- year-olds, 25 percent of the treatment group (14 of 55) were responders compared with 23 percent of the optical correction group (11 of 48). However, of the13- to 17- year-olds who had not previously been treated for amblyopia, 47 percent (eight of 17) responded to treatment compared to 20 percent (four of 20) who did not.
''Although our results indicate that visual acuity can be improved by treating amblyopia in older children, it is not known whether the improvement will be sustained after treatment is discontinued,'' the authors write. ''Therefore, a conclusion regarding the long-term benefit of treatment and the development of treatment recommendations for amblyopia in children seven years and older will need to await the results of a follow-up study we are conducting on the patients who responded to treatment.''
(Arch Ophthalmol. 2005; 123:437-447. Available post-embargo at www.archopthalmol.com.) - CHICAGO