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Updated: May 8, 2026

Rotating the Intraocular Lens to Prevent Posterior Capsular Opacification in Cataract Surgeries
Published on: July 7, 2023
Resolving refractive error after cataract surgery: IOL exchange, piggyback lens, or LASIK
Purpose:
To evaluate the efficacy, predictability, and safety of three different procedures (intraocular lens [IOL] exchange, piggyback lens implantation, and LASIK) to correct residual refractive error following cataract surgery.
Methods:
A retrospective multicenter study comprised 65 eyes of 54 patients that underwent phacoemulsification, resulting in a unacceptable final refractive error. Eyes were divided into three groups: eyes that had an IOL lens exchange (17 eyes), eyes that had a piggyback lens implanted (20 eyes), and eyes that had LASIK (28 eyes).
Results:
No differences between the IOL exchange and piggyback lens groups in the spherical equivalent, sphere, or cylinder were found (P = .072, .436, and .081, respectively). The LASIK group showed a statistically significant reduction in spherical equivalent and refractive cylinder when compared with the IOL exchange group (P < .001 and P = .001, respectively). The LASIK group showed statistically significant reduced refractive cylinder in comparison with the piggyback lens group (P = .002). The median efficacy index was 0.58 (range: 0.28 to 0.93), 0.75 (range: 0.65 to 0.92), and 0.91 (range: 0.85 to 1.14) in the IOL exchange, piggyback lens, and LASIK groups, respectively. Statistically significant differences were found between the IOL exchange and LASIK groups (P = .004) and the piggyback lens and LASIK groups (P = .003). No statistically significant differences were detected in the safety index among groups (P = .094). The predictability (±1 diopters of final spherical equivalent) was 62.5% of eyes in the IOL exchange group, 85% of eyes in the piggyback lens group, and 100% of eyes in the LASIK group.
Conclusions:
The three procedures were effective. The LASIK group showed the best outcomes in efficacy and predictability.
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