Phakic Intraocular Lens Implantation After Deep Anterior Lamellar Keratoplasty: Retrospective Case Series Analysis With Long-Term Follow-Up

Purpose: To report outcomes of phakic intraocular lens (IOL) implantation after deep anterior lamellar keratoplasty (DALK) to correct high ametropia.

Setting: Centro Hospitalar Universitário do Porto, Portugal.

Methods: Retrospective case series with 11 eyes submitted to phakic IOL implantation after DALK. Main outcomes measured were uncorrected and corrected distance visual acuity (UDVA and CDVA), refractive error components, tomographic parameters and endothelial cell density (ECD). The minimum follow-up was 3 years for all cases.

Results: Mean ECD loss was 8.7±6.7% at 1 year, 13.1±8.6% at 3 years (n=11; p=0.016, p=0.007, respectively) and 14.0±20.4% at 5 years (n=5, p=0.212). Mean logMAR UDVA increased from 1.27±0.90logMAR preoperatively to 0.16±0.15logMAR postoperatively (p≤0.001) and no statistically significant differences were registered during follow-up. All patients gained at least 5 lines of UDVA. 54.5% of the eyes gained 1 line in CDVA postoperative and only one eye lost one CDVA line through follow-up. Efficacy and safety indexes at 1 and 3 years were 1.01-0.97 and 1.24-1.21, respectively. Mean spherical equivalent was reduced from -7.84±4.63 D preoperatively to -1.05±1.07 D postoperatively (p=0.001). Mean percentage of reduction in refractive cylinder and spherical error was 83.8±15.8% and 73.1±31.5%, respectively, p≤0.001 for both. In one eye there was a significantly gradual ECD loss over 5 years follow-up and the patient will be submitted to IOL explant.

Conclusion: Phakic IOLs were effective for correction high ametropia after DALK, showing high efficacy and safety indexes with stability over time. However, it was registered a continuing endothelial cell loss postoperatively, which assumed to be higher than those reported in eyes without DALK.