Quantitative analysis of iris surface smoothness in normal population

This study aims to establish normative data for the Smoothness Index (SI) of the iris surface using Anterior Segment Optical Coherence Tomography (AS-OCT) in a healthy population. The study included 198 eyes from 99 subjects, 50 female and 49 males. The average age of participants was 46.71 ± 16.25, spanning 18-75 years. AS-OCT imaging was performed on both eyes before and after pupil dilation. The SI was calculated for various meridians of the iris. Participants were healthy individuals with no underlying iris pathologies, normal intraocular pressure, and a refractive error ranging from spherical equivalent (SE) -3.00 to + 3.00 diopters (D). The average SI was found to be 0.812 ± 0.036, with no significant differences between the eyes. The SI increased slightly with age and was higher in undilated pupils compared to dilated pupils. The study found no significant association between sex and the average SI. The normative range of SI across various meridians was established, providing a reference for future research on iris pathologies. This study highlights the SI pattern of normal iris in Iranians, which can be used for comparison in future research on iris pathologies. These findings are to be confirmed in a larger and more heterogeneous population.