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Review
. 2025 Jun 21:17:25158414251348882.
doi: 10.1177/25158414251348882. eCollection 2025 Jan-Dec.

Advances in IOL calculations in patients with keratoconus

Assaf Gershoni  1   2   3 , Graham D Barrett  2   3 , Ruti Sella  4
Affiliations
Review

Advances in IOL calculations in patients with keratoconus

Assaf Gershoni et al. Ther Adv Ophthalmol. .

Abstract

Keratoconus is a progressive ectatic corneal disease characterized by corneal thinning, steepening, and irregular astigmatism, presenting unique challenges for intraocular lens (IOL) calculations in cataract surgery. The use of traditional formulas for IOL calculations in eyes with keratoconus frequently leads to significant refractive prediction errors, often resulting in a hyperopic shift, which can lead to suboptimal outcomes and reduced patient satisfaction. This review examines the impact of keratoconus on IOL calculations and highlights recent advancements in formulas specifically designed for eyes with keratoconus, particularly the Barrett True-K and the Kane Keratoconus formulas. We assess the effectiveness of these formulas based on the current literature and provide clinical recommendations aimed at improving surgical outcomes in this complex patient group.

Keywords: Barrett True-K; IOL calculation formulas; Kane keratoconus; cataract surgery; clinical recommendations; corneal irregularities; intraocular lens (IOL) calculation; keratoconus; posterior corneal astigmatism; refractive prediction error; surgical outcomes.

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Conflict of interest statement

Prof Barrett is the developer of the Barrett suite of IOL formulas mentioned in this review. The other authors have no conflicts of interest to declare.

Figures

Figure 1.
Figure 1.
Clinical decision pathway for the perioperative management of cataract surgery in patients with stable keratoconus.
See this image and copyright information in PMC

References

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