Determining the Potential Role of Crystalline Lens Rise in Vaulting in Posterior Chamber Phakic Collamer Lens Surgery for Correction of Myopia

PURPOSE: To assess the effect of crystalline lens rise (CLR) on postoperative vault in eyes implanted with a phakic Visian Implantable Collamer Lens (ICL) (STAAR Surgical Company, Monrovia, CA) with a central port for myopic correction. METHODS: Non-invasive Fourier-domain swept-source anterior segment optical coherence tomography was used for dynamic assessment of the study eyes under changing light conditions. Phakic intraocular lens (IOL) vault, anterior chamber depth (ACD), and CLR were recorded after surgery, and intra-eye differences were analyzed under scotopic and photopic ambient light conditions. Inter-group analysis and regression analysis were performed to investigate any potential correlation between these biometric variables. RESULTS: This retrospective observational study comprised 111 eyes (65 patients) implanted with a myopic Visian ICL. The mean change in CLR from mydriasis to miosis was 59 +/- 60 mu m (P < .001). The sample was further divided into four groups according to the CLR value in miosis: CLR < 0, 0 to 200, 201 to 350, and > 350 mu m. A significant difference in central vault values was observed between the < 0 and > 350 mu m groups, the 0 to 200 and 201 to 350 mu m groups, and the 0 to 200 and > 350 mu m groups (P < .05). Eyes with a high vault value (> 750 mu m in mydriasis) had lower CLR values (P < .001) and higher ACD values (P < .001) than eyes with a low vault value (< 100 mu m in miosis). The linear correlation observed was negative between CLR and ACD, positive between postoperative vault and ACD, and negative between postoperative vault and CLR (P < .001). CONCLUSIONS: CLR significantly affected anterior chamber depth and postoperative ICL vault.