Intraocular Lens Formula Comparison of Flanged Intrascleral Intraocular Lens Fixation with Double Needle Technique

Abstract

Purpose: To analyze visual outcomes and accuracy of intraocular lens (IOL) calculation formulas in predicting postoperative outcomes in patients undergoing flanged intrascleral IOL fixation. Design: Case Series. Subjects: Twenty-three patients who had undergone secondary IOL placement using flanged intrascleral fixation technique. Methods: Retrospective chart review. Main Outcome Measures: Corrected distance visual acuity (CDVA) and postoperative spherical equivalent based on manifest refraction. Results: Visual acuity improved from 20/577 to 20/58. Overall, the actual refraction was 0.06 D more myopic than predicted. Holladay 2, Sanders Retzlaff Kraff/Theoretical (SRK/T) and Barrett Universal II resulted in mild myopic surprise (−0.55, −0.18 and −0.20 D). Haigis and Hill-RBF (Radial Basis Function) resulted in mild hyperopic surprise (+0.28 and +0.28 D). Hoffer Q and Holladay 1 were the most accurate (−0.02D and −0.08 D). Conclusion: Flanged intrascleral IOL fixation improved vision even in patients with other posterior segment pathologies. The effective lens positioning is likely similar to in-the-bag positioning. Hoffer Q and Holladay 1 formulas with in-the-bag calculations were the most accurate.