The Effect of Pupil Dilation on Ocular Biometry Measurements in the Senile Cataractous Eyes

Abstract

Objective: The study aimed to evaluate the effect of cycloplegia on the ocular biometric parameters and intraocular lens (IOL) power calculated by Sanders–Retzlaff–Kraff/Theoretical (SRK/T) formula in the cataractous eyes. Materials and Methods: This cross-sectional study included 68 senile cataractous eyes of 68 patients scheduled to undergo cataract surgery. Measurements of anterior chamber depth (ACD), axial length (AL), white-to-white (WtW) diameter, keratometry (K1, K2, Kmean), central corneal thickness (CCT), and pupil size (PS) were obtained with AL-Scan (Nidek Co., Ltd, Gamagori, Japan) before and after cycloplegia. The SRK/T formula was used to calculate IOL power with target refraction of 0 D. Cycloplegia induced by cyclopentolate hydrochloride %1. Results: The mean age of the patients was 70.60±4.07 years (range 65 to 80). A significant increase was observed in ACD after cycloplegia (p< 0.001). There was no statistically significant difference between pre-dilation and post-dilation AL, WtW, CCT, K1, K2, Kmean, and IOL power readings (p> 0.05). Two cases observed a decrease above 0.5 D of IOL power after cycloplegia. Conclusions: Cycloplegia induced by cyclopentolate hydrochloride %1 does not affect the measurement of the AL, WtW, CCT, keratometry, and SRK/T calculated IOL power except ACD in senile cataractous eyes.