Evaluation of the effect of tolterodine on pupil diameter and anterior chamber parameters with the Pentacam.

Background: To evaluate the effect of tolterodine on pupil diameter and anterior chamber parameters, including volume, depth, and angle, with the Pentacam.

Methods: The 56 eyes of 28 patients who were diagnosed as having overactive bladder and planned to be treated with tolterodine were followed up prospectively in the study. All the patients underwent full ophthalmic examination and scanning with the Pentacam (Oculus, Inc., Wetzlar, Germany) before and 4 weeks after the start date of tolterodine therapy. In addition, the 30 eyes of 15 healthy volunteers were analyzed twice as a control group for repeatability of the measurements.

Results: The quantitative descriptors of the anterior chamber before and after the treatment, respectively, were as follows: pupil diameter, 3.02 ± 0.56 mm and 3.01 ± 0.55 mm; anterior chamber depth, 2.74 ± 0.35 mm and 2.75 ± 0.34 mm; anterior chamber volume, 150.23 ± 33.95 mm(3) and 150.27 ± 34.48 mm(3); and anterior chamber angle, 34.56° ± 5.68° and 35.03° ± 5.99°. For all the measurements, the differences did not reach statistical significance (p > .05). Also, the comparison of the same parameters obtained from the first and second measurements of healthy volunteers was not statistically significant (p > .05).

Conclusion: Our study demonstrates that tolterodine does not affect pupil diameter and anterior chamber parameters, including angle, volume, and depth. Most likely, it is an organ-selective agent, inhibiting muscarinic receptors in the bladder rather than in the anterior segment of the eye.