Evaluation of lens parameters using anterior segment optical coherence tomography for zonular weakness risk in cataract surgery

Abstract Zonular weakness leads to deviation or dislocation of the crystalline lens; however, studies on this topic remain limited. We aimed to evaluate crystalline-lens parameters for risk stratification of zonular weakness in patients undergoing cataract surgery. This prospective comparative study included 28 eyes undergoing routine cataract surgery (control group), 28 requiring capsular tension ring (CTR) insertion due to intraoperative zonular weakness (CTR group), and 28 requiring intrascleral intraocular lens fixation due to zonular weakness or rupture (intrascleral fixation group). Preoperative non-mydriatic CASIA2 imaging (cataract mode) was used for measurements. FrontR was 9.15 ± 1.09, 8.30 ± 0.89, and 8.56 ± 0.97 mm in the control, CTR (p = 0.012), and the intrascleral fixation (p = 0.076) groups, respectively. Receiver operating characteristic (ROC) analysis of FrontR ≤ 8.58 mm showed an area under the curve (AUC) of 0.70, sensitivity of 72%, and specificity of 74%. Lens tilt was 5.18 ± 1.80° (control), 5.00 ± 1.90° (CTR, p = 0.95), and 6.67 ± 4.20° (intrascleral fixation, p = 0.33). Lens decentration was 0.188 ± 0.093 mm (control), 0.19 ± 0.12 mm (CTR, p = 0.78), and 0.34 ± 0.35 mm (intrascleral fixation, p = 0.039). ROC analysis of decentration ≥ 0.25 mm showed an AUC of 0.68, sensitivity of 56%, and specificity of 81%. In summary, a reduced FrontR (≤ 8.58 mm) was associated with mild-to-severe zonular weakness, whereas lens decentration (≥ 0.25 mm) was associated with severe weakness.