Myopic Correction with Iris-Fixated Phakic Intraocular Lenses: Twelve-Year Results

Abstract

Purpose. To evaluate a 12-year follow-up of myopic patients after iris-fixated phakic intraocular lenses (IF pIOLs) implantation. Setting. Ophthalmology Department, Military University Hospital in Prague (Czech Republic). Design. Single-center retrospective cohort study. Methods. We describe the results of a cohort study that included 85 eyes of 46 myopic patients who underwent implantation of Verisyse myopia, Veriflex, and Verisyse myopia toric (all Abbott Medical Optics, Inc.) intraocular lenses. Refractive functions and adverse events were assessed preoperatively, at 6 months, and 1, 2, 5, and 12 years after IF pIOL implantation. Results. Mean spherical equivalent was measured as −9.37 ± 2.87 D, 0.14 ± 0.61 D, and −0.42 ± 1.08 D, preoperatively, at 6 months and 12 years postoperatively, respectively. There was a significant reduction in the cylinder after surgery. At 12 years postoperatively, 90% of eyes had uncorrected distance visual acuity (UDVA) of 20/40 and 64% of 20/20. The safety index was 1.10 for the whole postoperative follow-up period. We found cataract formation in 3 eyes (3.5%). The endothelial cells loss (EC loss) directly caused by IF pIOL implantation was 6.0%, 8.10%, 12.8%, and 11.9%, at 1, 2, 5, and 12 years, respectively. In our cohort, 95% of eyes lost a higher percentage of EC than would be expected from a physiological loss at 12 years postoperatively. We found a significant negative interaction between preoperative pachymetry and EC loss, indicating that the lower pachymetry leads to a faster decline in endothelial cells density (ECD). IF pIOL re-enclavation was found in 28% of eyes. 7% of subluxations were caused by trauma. The mean time of nontraumatic re-enclavation was 6 years postoperatively. Conclusions. The study confirmed the advantages of IF pIOL implantation due to rapid visual recovery and stable visual function over the 12-year follow-up and also showed the influence of lower corneal pachymetry regarding EC loss.

Determination of Factors Associated With Long-Term Endothelial Loss and Refractive Result in Patients With Artisan Phakic Lens

“…This factor would be important in the context mentioned in a previous study by Galvis et al, where they mentioned a possible extrinsic mechanical factor, such as ocular rubbing or ocular compression when sleeping, as a possible cause of chronic endothelial loss in these patients. [8] Nemcova et al, in their recently published study, found an inverse correlation between baseline pachymetry and endothelial cell loss with a 12-year follow-up [18]. In the present study, an association between central corneal thickness and postoperative endothelial cell loss was not detected.…”

Long-Term Follow-Up of Corneal Endothelial Cell Changes After Iris-Fixated Phakic Intraocular Lens Explantation

“…4,18 Secondary corneal mechanical deformation due to ocular rubbing and nocturnal ocular compression related to the sleeping position leading to possible peripheral endothelial cell loss with irisclaw phakic IOL is also noteworthy. 4,19,20 The present results demonstrated that ECD continuously decreased postoperatively in the long-term follow-up despite safe pIOL explantation without intraoperative complications, use of dispersive viscoelastics, and minimization of operation time to reduce surgical trauma. Although normal ECD declines with age at rates of 0.6% per year, 5% to 6% every 10 years, and 3.5% to 5.7% after widely performed phacoemulsification, our results indicated that ECD had decreased by more than 25% 2 years after pIOL explantation.…”

“…4,18 Secondary corneal mechanical deformation due to ocular rubbing and nocturnal ocular compression related to the sleeping position leading to possible peripheral endothelial cell loss with iris-claw phakic IOL is also noteworthy. 4,19,20…”

Endothelzellverlust bei phaken Intraokularlinsen

“…10-12 Jahren wurde bei 0-15 % bzw. 6,3-20 % der Augen ein Endothelzellverlust von ≥ 25 % im Vergleich zur präoperativen Endothelzelldichte beobachtet [21,25,26]. Die Endothelzelldichte von < 1500 Zellen/mm 2 zeigte sich bei 0,8-3,2 % bzw.…”

“…3,5-4,0 % der Augen 5 bzw. 10-12 Jahre postoperativ [21,25]. Die Ergebnisse der Langzeitstudien mit einer Beobachtungsdauer von mindestens 5 Jahren sind in der ▶ Tab.…”