Résumé : | SIGNIFICANCE: It is apparent that a variety of biometric changes are caused by different types of cycloplegic eye drops. However, these effects are inconsistent and have not been reported in different refractive groups. PURPOSE: The purpose of this study was to determine the effect of cyclopentolate 1% on ocular biometric components in different types of refractive errors in children. METHODS: This cross-sectional study was conducted on 226 eyes of 113 schoolchildren in Shahroud, northeast Iran, with a mean ± standard deviation age of 9.20 ± 1.65 years. All participants had noncycloplegic and cycloplegic objective refraction using an autorefractometer. Cycloplegia was induced using cyclopentolate 1% eye drops. Biometric measurements were made with Allegro Biograph (WaveLight AG, Erlangen, Germany) before and after administering cycloplegic drops. Mixed-effect model regression was used to analyze the data. RESULTS: After cycloplegia, the vitreous chamber depth (VCD) (−0.043; 95% confidence interval [CI], −0.067 to −0.019 mm), lens thickness (−0.146; 95% CI, −0.175 to −0.117 mm), axial length (−0.009; 95% CI, −0.012 to −0.006 mm), and lens power (−0.335; 95% CI, −0.463 to −0.208 D) decreased significantly, whereas the anterior chamber depth (ACD) (0.183; 95% CI, 0.164 to 0.202 mm), anterior segment length (0.036; 95% CI, 0.014 to 0.058) mm), lens central point (0.109; 95% CI, 0.094 to 0.124 mm), and pupil diameter (1.599; 95% CI, 1.482 to 1.716 mm) increased (P value for all tests, |