Effect of topiramate on choroidal thickness and anterior chamber parameters in the treatment of patients with migraine.

Objective: To investigate the effects of topiramate on choroidal thickness and anterior chamber parameters using optical coherence tomography in the treatment of patients with migraine. Methods: A total of 22 eyes of 22 adults (12 females, 10 males) diagnosed with migraine and scheduled to topiramate treatment for pain control were recruited in this prospective study. Choroidal thickness (CT), anterior chamber depth (ACD), anterior chamber angle (ACA), spherical refractive equivalent (SphEq) and intraocular pressure (IOP) measurements were recorded at baseline (prior the topiramate therapy), first and second month visits for the statistical analysis. One-way ANOVA with repeated measures test was used for the statistical evaluation. Results: Mean age of the patients was 40.2 +/- 6.5 years. Mean CT at central fovea was 324 +/- 47 mm initially, 341 +/- 45 mm in the first month and 344 +/- 46 mm in the second month, thus first and second month measures were significantly higher than base values (p<0.001). There was also a slight increase in IOP values among baseline (15.5 +/- 2.4 mmHg) and follow-up visits (17.5 +/- 2.6 mmHg, 19.0 +/- 3.3 mmHg, respectively, p = 0.001). Baseline ACD (3.66 +/- 0.22 mm) measures significantly decreased at the first month (3.63 +/- 0.22 mm) and second month (3.62 +/- 0.22 mm, p = 0.009). Also, a significant reduction was detected in the first (36.2 +/- 4.9 degrees) and second month (35.9 +/- 5.1 degrees) ACA measures comparing with baseline (39.1 +/- 5.1 degrees, p = 0.05). A significant myopic shift was determined in the first and second month SphEq values (-0.08 +/- 0.6, -0.10 +/- 0.6, respectively, p = 0.05). Conclusions: The study revealed increased CT and altered anterior chamber parameters and IOP due to topiramate therapy. Therefore, the patients using topiramate should be carefully monitored by an ophthalmologist considering the possible side effects.