Intraocular pressure at different gaze positions in patients with highly myopic strabismus.

Purpose: To evaluate intraocular pressure (IOP) at different gaze positions in patients with highly myopic strabismus (HMS).

Study Design: Nonrandomized, prospective, observational study.

Methods: This study included 18 eyes of 14 patients with HMS and 51 eyes of 51 age-matched controls without strabismus; these were further divided into two groups based on refractive errors: > -6.00 diopter (D) (n = 22 eyes) and ≤ -6.00 D (n = 29 eyes). IOP was measured in primary and side gazes and compared within and among groups. The relationships between IOPs and axial length, angle of globe dislocation measured on magnetic resonance imaging, strabismus angle, and degree of abduction deficit were studied.

Results: The HMS group showed higher IOP in abduction (19.3 ± 4.9 mmHg) than in the primary (12.5 ± 4.3 mmHg) and adducting positions (13.0 ± 3.3 mmHg), (p < 0.001). The IOP in the adducting position in the HMS group (13.0 ± 3.3 mmHg) was lower than in the control groups both with (17.6 ± 3.5 mmHg) and without (16.9 ± 4.1 mmHg) high myopia, ; (p < 0.001 and = 0.003). The difference in IOP between abduction and adduction was significantly larger in the HMS group (6.4 ± 4.6 mmHg) compared to others (p < 0.001) and positively correlated with the strabismus angle and the angle of globe dislocation and negatively with abduction deficit.

Conclusion: The IOP of patients with HMS changes dramatically on side gazes, therefore, care should be taken while measuring IOP.