To evaluate the effectiveness of CAM visual stimulation in amblyopia treatment in 7-20 years old patients

In this study, amblyopic patients in the age range of 7 to 20 were recruited from a private optometry/ophthalmology clinic in Gillan-e-Gharb, Iran, in 2017. According to the initial best corrected visual acuity (VA), amblyopia was categorized into three levels: mild (VA between 0.15-0.3logMAR), moderate (VA between 0.3- 0.55logMAR), and severe (VA≥ 0.55 log MAR). The patients were divided into two therapy groups: occlusion group versus CAM visual stimulation group. In the occlusion group, the patients were recommended to patch the non-amblyopic eye for 4-6 hours daily plus near activities such as playing computer games while patching. In CAM group, performed in office 2-3 times weekly, with the amblyopic eye, the patients watched a high contrast square wave grating rotating plate, with spatial frequency 1 line higher than the patient detection, while drawing on the transparent disk for 20 minutes. Follow up visits were performed after 1st, 2nd, 3rd month of the initiation of therapy.

After 3 months, in the occlusion group, the VA improvements were 0.32±0.18logMAR, 0.10±0.12logMAR, and 0.04±0.04 logMAR respectively in severe, moderate, and mild groups (p=.56). The improvement of VA in CAM groups were 0.54 ±0.11logMAR, 0.24±0.10logMAR, and 0.13±0.04logMAR in severe, moderate, and mild groups, respectively (P< 0.001).

In the age range of 7-20 years, CAM therapy was more effective than occlusion therapy specially in the severe group. Considering that occlusion is not socially acceptable for older children or younger adults and might create disability in performing certain tasks, CAM offers a good alternative to conventional method.