Author Affiliations: Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou (Drs Zhao, Zhang, and Lam); Department of Ophthalmology and Visual Sciences (Drs Chen, A. H. Fan, Zhao, D. S. P. Fan, and Lam), Institute of Chinese Medicine (Drs Leung and Lam), the Chinese University of Hong Kong, Hong Kong; Einhorn Clinical Research Center, New York Eye and Ear Infirmary, New York (Dr Ritch); and the Department of Ophthalmology, New York Medical College, Valhalla (Dr Ritch).
We appreciate Dr Lempert's interest in our article.1 He considered our study as well as a group of other studies that compared the effectiveness of different therapies to that of patching to be poorly controlled because they lacked an untreated group, raising a concern that “their reported benefits can be explained by the traditional educational remedial techniques with which they are usually combined.” We agree with Lempert that an untreated control group is useful to help evaluate the effects of treatments (ie, acupuncture and patching) that were combined with optical correction (refractive adaptation) in our study. However, as mentioned in our article, optimum optical correction is effective for anisometropic amblyopia in children aged 3 to 7 years,2 whereas in children aged 7 to 12 years, the response rate (approximately 30%) is much lower with optical correction alone.3 Therefore, combined treatment with optical correction and patching should be the benchmark treatment for children aged 7 to 12 years. There could thus be an ethical issue if we included a group of children who had optical correction alone for a period of 10 months (ie, 16 weeks of washout period plus 25 weeks with active treatment). Moreover, it has been shown that most visual acuity improvement due to optical correction was achieved before 15 weeks.2,4,5 Because we randomized our study participants after a spectacle-only washout period of at least 16 weeks or until stabilization of visual acuity was achieved,1 the contribution to visual improvement from continuous refractive adaptation would be minimal, if any, in our study.
Chen LJ, Fan AH, Zhao J, Fan DSP, Zhang M, Leung PC, Ritch R, Lam DSC. Acupuncture and Amblyopia—Reply. Arch Ophthalmol. 2011;129(7):962-963. doi:10.1001/archophthalmol.2011.154