ASSOCIATION BETWEEN AGE AND CYCLOPLEGIA-INDUCED CORNEAL AND ANTERIOR SEGMENT CHANGES

To evaluate the effects of cycloplegia on corneal topography and anterior segment parameters, and to investigate the correlation between these changes and age.

Department of Ophthalmology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Türkiye.

A total of 132 subjects (264 eyes) aged between 5 and 60 years were included in this study. The sample size was calculated based on a probability of 0.5, a 95% confidence interval, and a critical value of 1.96. Detailed ophthalmologic examination and corneal topography evaluations were performed for all participants using the Pentacam® AXL device (Oculus, Germany). Pre- and post-cycloplegia measurements included flat (K1), steep (K2), mean (Kmean), and maximum keratometry (Kmax); corneal volume (CV) and total corneal densitometry (CD); central corneal thickness (CCT); anterior chamber depth (ACD); and anterior chamber volume (ACV). Statistical analysis was performed on the changes in these parameters following cycloplegia.

The mean age of the participants was 32.6±16.6 years (range: 5–60), with 53 males (40.2%) and 79 females (59.8%). Comparisons of measurements before and after cycloplegia revealed statistically significant increases in mean K2 (44.11±1.52 vs. 44.12±1.52), Kmean (43.45±1.39 vs. 43.46±1.39), ACD (2.99±0.40 vs. 3.07±0.38), and ACV (178.5±46.3 vs. 187.3±37.2) (all p<0.05). CCT decreased significantly (549.5±37.1 to 548.3±36.3, p=0.01). No significant changes were observed in K1 (42.80±1.42 vs. 42.83±1.43), Kmax (44.68±1.61 vs. 44.67±1.68), CV (60.7±3.6 vs. 60.5±3.6), or CD (16.5±4.0 vs. 16.3±3.5) (p>0.05). A significant positive correlation was observed between age and the increase in mean K2 after cycloplegia (r=0.295, p=0.015). No statistically significant correlation was observed between age and changes in other parameters (p>0.05 for all).

Cycloplegia induces measurable alterations in corneal curvature and anterior segment configuration, particularly an increase in K2, ACD, and ACV, accompanied by a slight reduction in CCT. The positive correlation between age and the increase in K2 suggests a greater corneal steepening response to cycloplegia in older individuals. These findings highlight the importance of considering age-related variations when interpreting biometric and topographic measurements obtained under cycloplegic conditions.