The effect of 2% pilocarpine on depth of field in different time intervals among presbyopic subjects.

PURPOSE

The aim of this study was to determine the effects of 2% pilocarpine ophthalmic solution on the depth of field and the pupil size of human eye in the presbyopic population.

SETTINGS AND DESIGN

Prospective experimental study.

METHODS

The prospective study included 120 presbyopic people aged between 40 and 55. All willing subjects underwent a comprehensive eye examination that included measuring the visual acuity for distance and near, retinoscopy, refraction, anterior and posterior segment examination, depth of field, and pupil size in room illumination. Following a preliminary examination, 2% pilocarpine ophthalmic solution was instilled in both eyes, and after various intervals of 15, 30, and 45 min, the depth of field and the pupil size were measured.

RESULTS

Before instillation of 2% pilocarpine solution, the mean pupil size was 0.34 mm with a standard deviation (SD) of ±0.37. After instillation, the mean pupil size changed to 2.20, 1.91, and 1.57 mm with SD of ±0.43, ±0.27, and ±0.34 mm, respectively, in 15, 30, and 45 min time intervals. Initial mean depth of field also changed from 1.76 D (SD ± 0.20) to 1.72, 1.65, and 1.59 D with SD of ±0.20, ±0.16, and ±0.22 D, respectively, in 15, 30, and 45 min time intervals.

CONCLUSION

The study concludes that pupillary miotics create a pinhole effect after the instillation of 2% pilocarpine ophthalmic drop, extending the depth of field. The effect was highly clinically significant at 45 min with a P value <0.001.