To analyze the pharmacologic effect of atropine penalization in amblyopic eyes.

Distant and near visual acuity, near point of accommodation (NPA), and pupil size were measured in the sound eye of 40 children with amblyopia before and after receiving atropine sulfate 1% solution. Amblyopic children were divided into 2 groups according to the time of follow-up visit: 4-days and 7-days after injection; the same tests were performed on all the scheduled follow-up visits. This study included a control group of 20 normal children who received the same test on the initial visit and the scheduled follow-up visits.

Visual acuity of the sound eye at distance showed greater decreases in children with 4-day follow-up visits compared with 7-day visits in the amblyopic group ( p = 0.24). There was no significant difference in near visual acuity between the amblyopic group and the normal control group by follow-up interval ( p = 0.98, p = 0.75). Near point of accommodation significantly increased in the 4-day visit group in both the amblyopic and the normal control groups ( p = 0.04 and p = 0.03, respectively), Pupil size was significantly maintained in the 4-day visit, amblyopic group ( p = 0.01).

Atropine effectively decreased the vision of the sound eye in amblyopic children. However, to maintain the pharmacologic effect, two separate atropine instillations per week (on a weekday and the weekend) should be considered as a treatment for amblyopia.