Geometric Morphometric Anatomy of the Lacrimal Punctum in Normal Population: Punctum Update (PUP) Study – Paper 5

Background To investigate the geometric morphological differences of the lacrimal punctum by analyzing its shape in relation to age and sex in a normal population. Methods 960 high-magnification slit-lamp images were obtained from 320 puncta of normal asymptomatic Indian individuals across eight decades of life. Using advanced geometric morphometric techniques, including Elliptic Fourier Analysis and Principal Component Analysis, the intricate details of the lacrimal punctum's shape in a diverse population sample were categorized by age and sex. High-resolution images of the lacrimal punctum underwent standardization for scale and orientation, followed by precise landmark identification and coordinate data extraction. Results The geometric morphometry of the lacrimal punctum shows significant changes as one ages. However, the gender differences, in isolation, without consideration of age, remain subtle and are not pronounced. Interestingly, detailed Principal Component scores analysis revealed potential sex- and age-related variations specifically for the left and right lower puncta, which warrant further investigation. These changes could reflect unique aging changes in the proximal lacrimal drainage system. Conclusion The study is a starting point for geometric morphometric analysis of the lacrimal punctum and provides valuable insights into the punctal changes in size, orientation, and overall morphology across different age groups and between sexes. These findings highlight the significance of considering individual age-wise anatomical variations to better understand the lacrimal punctum.