Postoperative Shifts in Adult Strabismus Patients with Visual Deficits

To evaluate the effects of corrective surgery in adult strabismic patients with visual deficits and the stability of postoperative alignments.

Retrospective study. Alignment and binocular visual function were evaluated in adult patients with visual deficits (best corrective visual acuity (BCVA) <0.3 in one or both eyes) with at least 6 months postoperative follow-up. The results in these patients were compared to those in patients with normal or nearly normal vision (BCVA ≥ 0.6 in the worse eye) matched by the type of strabismus, magnitude of deviation, age at the time of corrective surgery, and length of time before final follow-up.

Sixty-four patients aged 28.3 ± 12.0 (17~65) years were included in the visual deficit group, and 64 subjects aged 26.8 ± 9.4 (17~58) years were included in the matched control group. No significant difference was found in the age or deviation angle between the two groups. The surgery was considered a success in 42 patients (65.6%) in the visual deficit group and 55 patients (86%) in the control group at the last visit (Χ² = 7.19, p = 0.008). Normal or partially normal stereo acuity was achieved by three patients in the visual deficit group and 29 patients in the control group. An average shift toward exotropia of 7.3 prism diopter (PD) in the visual deficit group and 4.9 PD in the control group was observed between postoperative day 1 and the final visit (t = 2.08, p = 0.04). Of the 22 patients in the visual deficit group that were defined as "not a success," 20 were under-corrected, and two were over-corrected.

Adults with poor vision experienced positive results from corrective surgery via a postoperative shift toward exotropia. Full correction of deviation and postoperative shift should be considered before surgery.