The Non-uniform Distribution of Horizontal and Vertical Crystalline Lens Rise Using Optical Coherence Tomography

Abstract

Purpose: To observe the crystalline lens rise (CLR) in horizontal and vertical orientations using anterior segment optical coherence tomography (AS-OCT). Methods: Non-invasive swept-source AS-OCT was used to measure the lens thickness, CLR, and angle-to-angle distance (ATA) in both the horizontal and vertical orientations. Anterior chamber depth (ACD) and horizontal white-to-white corneal diameter were obtained using the Pentacam HR (Oculus Optikgeräte GmbH). Axial length was obtained using the IOLMaster 700 (Carl Zeiss Meditec AG). The paired t test was used to analyze the difference in CLR between the two orientations. Pearson correlation analysis was performed to investigate the correlations between CLR and other ocular variables. Results: This prospective observational study comprised 99 eyes (99 patients) that underwent Visian Implantable Collamer Lens (STAAR Surgical) implantation for myopic correction. The mean CLR was 64.29 ± 168.04 and 208.09 ± 173.12 µm in the horizontal and vertical orientations, respectively. The vertical CLR (VCLR) was significantly greater than the horizontal CLR (HCLR) ( P < .05). Both the HCLR and VCLR were positively correlated with lens thickness and negatively correlated with ACD (all P < .05). The difference in CLR (VCLR-HCLR) was positively correlated with the axial length and the difference in ATA between the two orientations ( P < .05). Conclusions: VCLR was greater than HCLR in most patients with myopia, especially in the longer eyes. This nonuniform distribution in CLR implied different placements of the iridocorneal angles in the horizontal and vertical orientations and should be considered for the selection of ICL size and placement position. [ J Refract Surg . 2023;39(5):354–359.]

Causes and management strategies for elevated intraocular pressure after implantable collamer lens implantation

“…The study showed that ICL diameter and ACD were the most influential factors, a relatively larger ICL diameter and a greater preoperative ACD directly result in higher postoperative vault. In addition, CLR, refers to the anterior movement of the natural crystalline lens within the eye, is also an important factor in ICL surgery ( 31 ). CRL can affect the position and movement of the natural lens and the ICL, excessive CLR can lead to potential complications such as contact between the ICL and the natural lens, which may result in elevated IOP.…”