Fixation stability in posttreatment unilateral amblyopia using the MP1 microperimeter

1. Takafumi Mori¹
2. Kaori Saito¹
3. Akiko Sakamoto¹
4. Teiko Hashimoto²
5. Keiko Yago³
6. Tomohiro Iida¹

¹Fukushima Medical University, Fukushima, Japan
²Sakuramizu Sakai Eye Clinic, Fukushima, Japan
³Northern Fukushima Medical Center, Date, Japan

Purpose: To evaluate the characteristics of fixation stability in posttreatment unilateral amblyopia using microperimetry.

Methods: Twelve patients with treated unilateral amblyopia (age: 11-19 years) were assessed. Eye position was recorded using the MP1 during a fixation task. Fixation score and central 2 degrees and central 4 degrees values were obtained from the MP1. Distances between each fixation point from the center of gravity were calculated from raw fixation data.

Results: Best corrected visual acuity in amblyopic eye was 20/20 or better in 10 eyes, 20/25 in 1 eye and 20/32 in 1 eye. Of the 12 patients, all amblyopic eyes and all non-amblyopic eyes showed "stable" fixation. The mean value of distances between each fixation point from the center of gravity was 0.33±0.09 degrees in amblyopic eye and 0.20±0.05 degrees in non-amblyopic eye. In all patients, amblyopic eye had greater mean value than non-amblyopic eye.

Conclusions: Compared with non-amblyopic eye, amblyopic eye showed wandering fixation, even in good visual acuity.