Accuracy of formulae for secondary intraocular lens power calculations in pediatric aphakia

• Main Authors: Fouad R. Nakhli, Khaled Emarah, Laila Jeddawi
• Format: Article
• Language: English
• Published: Wolters Kluwer Medknow Publications 2017-09-01
• Series: Journal of Current Ophthalmology
• Online Access: http://www.sciencedirect.com/science/article/pii/S2452232517300033

Purpose: To compare the accuracy of axial length vergence formulas versus refractive vergence formulas for secondary intraocular lens (IOL) implantation in pediatric aphakia. Methods: This retrospective comparative study, evaluated 31 eyes of 31 patients aged ≤3.5 years, who had undergone secondary IOL implantation. The median absolute error (MedAE) was compared between axial length vergence formulas (Hoffer Q, Holladay I, SRK II, and SRK/T) and refractive vergence formulas (Lanchulev, Holladay R, Mackool, and Khan) as well as between formulas within the same vergence. Results: There was a significant difference (P = 0.010) between MedAE for axial length vergence formulas [1.19 Diopter(D)] and MedAE for refractive vergence formulas (2.48 D). The MedAE of axial length vergence formulas were comparable as to Hoffer (1.59 D), Holladay (1.27 D), SRK/T (1.23 D), and SRK II (1.30 D). Among refractive vergence formulas, Lanchulev (5.00 D) and Holladay R (2.51 D) had significantly larger MedAE as compared to Khan (2.06 D) and Mackool (2.15 D). Conclusion: Axial length vergence formulas performed significantly better than refractive vergence formulas; however, axial length vergence formulas were comparable within the same vergence. Keywords: Axial length, Refractive, Intraocular lens, Pediatric, Aphakia, Intraocular lens power calculation