Brillouin Metrics of the Crystalline Lens Comparison Between Low-Medium Myopia and High Myopia

To investigate the impact of myopia on the Brillouin biomechanics and morphology of crystalline lenses in Chinese adults.

Patients with myopia were enrolled and divided into low-medium (spherical equivalent [SE] ≥ -5.75 D, N = 66) and high (SE ≤ -6.0 D, N = 72) myopia groups. All patients underwent routine ophthalmic examinations, including SE, axial length, and anterior chamber metrics (Pentacam) measurements. The Brillouin-related metrics of the crystalline lenses were measured using a Brillouin microscopy. The morphological parameters included the Width of Top Plateau (WTP), Width of Bottom Plateau (WBP), Bottom-Top (B-T), Slope of Anterior Cortex (SAC), and Slope of Posterior Cortex (SPC). The height of Plateau was a biomechanical parameter.

The study included 138 eyes (138 patients); the mean age was 28.43 ± 8.31 years. WBP, B-T, SAC, and SPC significantly differed between the high and low-medium myopia groups (all P<0.05). WBP, B-T, and SPC significantly correlated with SE in the high myopia group (Pearson's r = 0.365, 0.287, and 0.294, respectively; all P<0.05) but not in the low-medium group. The SPC significantly decreased for all participants based on the SE values (P<0.05). The biomechanics and thickness of the nucleus displayed no discrepancies with SE in all participants (all P >0.05).

An increase in the degree of myopia could be associated with posterior cortex thickening while maintaining stable biomechanics and morphology of the crystalline lens nucleus. Brillouin microscopy can serve as an effective technique for multidisciplinary lens biomechanical and morphological imaging.