Anterior segment characteristics and spatial variations of different crystalline lens diseases

Introduction

To evaluate anterior chamber and crystalline lens morphology in patients with cataracts, lens subluxation (LS), and microspherophakia (MSP) using three anterior segment (AS) imaging instruments, and to develop a novel method for assessing the spatial characteristics of crystalline lens position through anterior chamber morphology measurements.

Methods

We examined 98 eyes (19 normal, 25 cataracts, 27 LS, 27 MSP) using AS optical coherence tomography (AS-OCT), ultrasound biomicroscopy (UBM), and IOLMaster700. Measurements included corneal thickness, anterior chamber parameters, and lens thickness (LT). We introduced the coefficient of variation (CV) of anterior chamber angle (ACA) and angle open distance (AOD) to quantify lens dislocation, and generated lens position alteration maps using AS-OCT and UBM to visualize the extent and distribution of lens dislocation.

Results

The LS and MSP groups showed significantly greater LT compared to normal and cataract groups (P < 0.05). The nasal ACA was reduced in LS and MSP groups, with MSP showing smaller nasal AOD compared to normal group (P < 0.05). Temporal ACA was significantly lower in the LS group compared to other groups (P < 0.05). AS-OCT measurements of ACA and AOD in the MSP group exceeded UBM values. The CV measurements and lens location alterations maps effectively illustrated the extent of lens dislocation and zonular weakness.

Conclusion

Each condition showed distinct AS features. The CV of ACA and AOD, along with location alteration maps from wide-field AS-OCT and UBM, might serve as valuable tools in diagnosing lens dislocation-related diseases, identifying dislocation areas, and assessing zonular weakness.

Trial registration number: NCT04833491 (ClinicalTrials.gov.)