Ultrasound biomicroscopy analysis of age-related trends in lens stability in cortical cataracts

To investigate age-related differences in the iris-lens angle (ILA) among patients with age-related cortical cataracts and elucidate the impact of age on lens stability.

A prospective observational study was conducted on patients with age-related cortical cataracts scheduled for phacoemulsification surgery. Preoperative ultrasound biomicroscopy (UBM) images were collected and analyzed. Initially, patients were stratified into two age groups: <60y and ≥60y, with no significant intergroup differences in sex or eye laterality. For further analysis, participants were subdivided into three age strata: <60y, 60-75y, and >75y. The ILA was measured in four quadrants (superior, inferior, nasal, and temporal). Intergroup differences in ILA were compared, and correlations between age and ILA parameters were analyzed using statistical methods.

The sample data were categorized into three groups according to age, <60y (113 patients; 55.8% female), 60-75y (245 patients; 61.0% female), and >75y (70 patients; 50.2% female). The superior quadrant ILA increased progressively with age stratification (P=0.02), and the maximum ILA difference (ΔILA) was significantly higher in patients over 75y (P<0.01). Simple linear regression analysis demonstrated a positive correlation between age and ILA in the superior (Y=7.487+0.096X, R=0.191, P<0.001) and temporal (Y=10.254+0.052X, R=0.104, P=0.032) quadrants. Additionally, the mean ILA across all quadrants (ILA_mean) and ΔILA were positively correlated with age (ILA_mean: Y=9.721+0.055X, R=0.138, P=0.004; ΔILA: Y=3.267+0.044X, R=0.006, P<0.05).

In patients with age-related cortical cataracts, ILA increases with age, particularly in the superior and temporal quadrants, suggesting that advanced age is associated with greater lens deviation and decreased lens stability. UBM imaging can effectively evaluate the status of the zonule and lens stability, providing crucial evidence for personalized surgical planning based on patients' age.