Residual Anterior Chamber Depth And Angle Correlation Following Implantable Collamer Lens Surgery

To assess the residual anterior chamber depth (RACD) after Implantable Collamer Lens (ICL) implantation and its relationship with the anterior chamber angle (ACA).

The study was conducted at five Aier Eye Hospitals in China, located in Changsha, Nanchang, Zhuzhou, Hengyang, and Yueyang, as a multicenter, retrospective study.

This study was divided into two stages. In the first stage, data from 1810 eyes that underwent ICL implantation across four hospitals were analyzed to evaluate RACD. In the second stage, 123 eyes from one hospital were used to explore the correlation between RACD and postoperative ACA measurements using anterior segment optical coherence tomography (AS-OCT). Additionally, 33 eyes were assessed for differences in postoperative ACA measurements when taken perpendicular and parallel to the ICL axis.

In the first stage, the mean RACD was 2.30 ± 0.25 mm, with a mean lens vault (LV) of 460.91 ± 222.07 μm. Approximately 11.10% (201 eyes) had a RACD ≤ 2.0 mm, which was associated with a higher LV (709.97 ± 250.52 μm). Among all eyes, 62.19% had an LV within the range of 250-750 μm. There were no significant differences in postoperative visual acuity and intraocular pressure among eyes with varying RACD values. In the second stage, four ocular variables were found to correlate with postoperative ACA, with RACD being the only significant factor included in the regression equation for ACA (R² = 0.521). No significant difference in postoperative ACA was found when measured perpendicular or parallel to the ICL.

A subset of patients exhibited an optimal LV with RACD ≤ 2.0 mm after ICL implantation. Shallow RACD was strongly correlated with a narrower postoperative ACA. These findings highlight the importance of considering RACD in postoperative ACA predictions and the potential need for individualized adjustments in ICL implantation to optimize patient outcomes.