Outcomes of coaxial micro-incision phacoemulsification in nanophthalmic eyes: report of retrospective case series

Purpose: The surgical risk and complication rate after cataract surgery are extremely high in patients with nanophthalmos. This study is designed to compare the visual and refractive outcomes before and after coaxial micro-incision phacoemulsification and evaluate postoperative complications. Methods: Fifty nine patients (89 eyes) with axial length (AL) < 21 mm diagnosed with nanophthalmos were enrolled in this retrospective study. All patients underwent coaxial micro-incision phacoemulsification and IOL implantation. The main outcome measures included anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), intraocular pressure (IOP) and best corrected visual acuity (BCVA). Wilcoxon signed rank test or Mann-Whitney test, and Chi-square test and logistic regression analysis were performed for statistical tests as appropriate. Results: The median AL was 19.63 mm. Sixty six eyes (74.16%) had a history of surgical intervention. Postoperative ACD, ACV and ACA were increased significantly (all P<0.001), whereas postoperative IOP was decreased significantly (P<0.001) after surgery. Previous surgical intervention was related to a reduction in the postoperative ACD and ACA (P<0.01), and both preoperative and postoperative IOP (P<0.001). Postoperative BCVA was improved in 94.38% of the cases. Intraoperative complications mainly included iridoschisis (6 eyes, 6.74%). Early postoperative complications included temporary corneal edema (TCE) (23 eyes, 25.84%), anterior inflammatory response (AIR) (19 eyes, 21.35%), cystoid macular edema (CME) (14 eyes, 15.73%), and uveal effusion (4 eyes, 4.49%). Late postoperative complications included CME (8 eyes, 8.99%), uveal effusion (8 eyes, 8.99%), malignant glaucoma (2 eyes, 2.25%) and posterior capsular opacification (PCO) (10 eyes, 11.24%). The majority of complications (80%) were successfully resolved by pharmacotherapy or operation. The risk of surgical complications was greater in patients with lower AL, ACD, ACV or ACA and higher nuclear hardness or mean keratometry (Km). Conclusion: With reasonable preoperative management, prudent selection of the lens, rigorous surgical technique and unerring cognition of potential complications, coaxial micro-incision phacoemulsification lens surgery can be performed in patients with nanophthalmos and yield favorable outcomes and a low incidence of complications.