Influence of intraocular lens haptic design on refractive error

J Cataract Refract Surg. 2014 Sep;40(9):1473-8. doi: 10.1016/j.jcrs.2013.12.018.

Abstract

Purpose: To assess the influence of intraocular (IOL) haptic design on the refraction prediction error in patients having cataract surgery.

Setting: Private practice.

Design: Comparative case series.

Methods: Corneal power and axial length were measured with the same devices in eyes with a 3-piece Acrysof IOL and eyes with a 1-piece Acrysof IOL and were entered into the Haigis, Hoffer Q, Holladay 1, and SRK/T formulas. The median absolute error and mean absolute error in refraction prediction (ie, difference between expected refraction and actual refraction) were assessed 1 month postoperatively.

Results: The study evaluated 110 eyes with the 3-piece IOL and 84 eyes with the 1-piece IOL. With all formulas, the median absolute error was lower with the 3-piece IOL. It ranged between 0.15 diopter (D) (Haigis and Holladay 1) and 0.19 D (SRK/T) with the 3-piece IOL and between 0.23 D (Haigis) and 0.30 D (SRK/T) with the 1-piece IOL. With all formulas, a higher percentage of eyes with the 3-piece IOL were within ±0.25 D and ±0.50 D of the target refraction.

Conclusions: Three-piece IOLs may yield better refractive outcomes than 1-piece IOLs. A possible reason is that once the early forward IOL shift previously observed with the 3-piece design occurs because of the haptic-compression force decay typical of these IOLs, the rigid haptics of 3-piece IOLs still exert more pressure against the capsular bag than the haptics of 1-piece IOLs. Therefore, 3-piece IOLs may better resist subsequent capsule contraction and provide a more predictable effective lens position.

Financial disclosure: Dr. Hoffer receives royalties for his book IOL Power, Slack, Inc., and formula royalties from all manufacturers using the Hoffer Q formula. No other author has a financial or proprietary interest in any material or method mentioned.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Algorithms
  • Axial Length, Eye / physiopathology
  • Cornea / physiopathology*
  • Female
  • Humans
  • Lens Implantation, Intraocular*
  • Lenses, Intraocular*
  • Male
  • Optics and Photonics
  • Phacoemulsification*
  • Prosthesis Design*
  • Refraction, Ocular / physiology
  • Refractive Errors / physiopathology*
  • Retrospective Studies
  • Visual Acuity / physiology*