Iris-Fixated Phakic Intraocular Lenses: New Results

Comparative study of small-incision lenticule extraction and phakic intraocular lens implantation for the correction of high myopia: 6-year results

PURPOSE

To compare the long-term safety, efficacy, and complications of small-incision lenticule extraction (SMILE) and flexible iris-fixated anterior chamber phakic intraocular lens (pIOL) implantation for the treatment of high myopia.

SETTING

University of Health Science Turkey, Beyoğlu Eye Training and Research Hospital, İstanbul, Turkey.

DESIGN

Retrospective comparative case series.

METHODS

Data of patients who underwent SMILE or pIOL (Artiflex) implantation for myopia were retrospectively reviewed. Only patients with preoperative manifest refraction spherical equivalent from -6.00 to -10.00 diopters (D) were included in the study.

RESULTS

There were 47 eyes of 32 patients in the SMILE group and 52 eyes of 29 patients in the pIOL group. The mean postoperative follow-up was 63.75 ± 18.40 months in the SMILE group and 65.38 ± 16.22 months in the p-IOL group (P = .71). At 6 years postoperatively, refractive predictability was slightly better in the pIOL group, and the percentages of eyes within ±0.50 D of the attempted correction were 77% and 83% in the SMILE and pIOL groups, respectively. Although mean uncorrected distance visual acuity was comparable (SMILE, 0.12 ± 0.06 logarithm of the minimum angle of resolution [logMAR]; p-IOL, 0.09 ± 0.05 logMAR), the safety indices (1.08 ± 0.22 vs 1.11 ± 0.20; P = .02) and the efficacy indices (0.92 ± 0.24 vs 1.11 ± 0.22; P = .03) were statistically significantly higher after pIOL implantation. Despite a mean of 11.09% of the endothelial cell being lost at 6 years after pIOL implantation, no pIOL was explanted due to endothelial cell loss.

CONCLUSIONS

In this comparative and long-term study, iris-fixated anterior chamber pIOL implantation for high myopic correction showed slightly better safety and efficacy profiles but with statistically significant endothelial cell loss.

Eight-year follow-up of Artiflex and Artiflex Toric phakic intraocular lens

PURPOSE

To analyse long-term efficacy, safety, visual and refractive stability and physiological changes of Artiflex Myopia and Toric phakic intraocular lenses (pIOL) separately throughout an 8-year follow-up.

DESIGN

Retrospective cohort study.

METHODS

A total of 67 eyes of 37 patients underwent Artiflex Myopia (47 eyes) or Artiflex Toric (20 eyes) implantation for correcting myopia and/or astigmatism. Follow-up evaluations were performed 1, 3, 5 and 8 years after surgery. Preoperative and postoperative data included corrected (CDVA) and uncorrected distance visual acuity (UDVA), manifest refraction, endothelial cell density (ECD) and intraocular pressure (IOP) assessments. Efficacy and safety indexes were analysed. The vectorial analysis was performed using the Thibos method.

RESULTS

Mean CDVA and UDVA of both pIOLs significantly improved from preoperative to 1 year after implantation, and then it remained stable over the 8-year follow-up. The efficacy and safety indexes after 8 years were 0.94 ± 0.16 and 1.07 ± 0.18 for Artiflex Myopia and 1.00 ± 0.11 and 1.10 ± 0.15 for Artiflex Toric, respectively. The spherical equivalent (SE) significantly improved after surgery. J0, J45 and SE refractive components showed no changes between postoperative visits. A total ECD loss of 4.8% (p < 0.001) and 10.4% (p = 0.005) was found after 8 years for Artiflex Myopia and Toric, respectively.

CONCLUSIONS

Artiflex Myopia and Toric pIOLs are a safe, efficient and predictable option for the correction of myopia and/or astigmatism. The vectorial analysis showed excellent rotation stability for the toric version.

Ten-year safety follow-up and post-explant analysis of an anterior chamber phakic IOL

PURPOSE

To assess endothelial cell loss (ECL) rate and collect safety data in patients with AcrySof L-series Cachet phakic intraocular lens (pIOL) up to 10 years post-implantation.

SETTING

Clinical settings in the United States, European Union, and Canada.

DESIGN

Nonrandomized, observational, open-label safety study.

METHODS

Central and peripheral endothelial cell density was evaluated and compared with 6-month post-implantation baseline. Nonlinear analysis was performed to identify factors affecting post-explantation ECL. Additional evaluations included uncorrected visual acuity (UCVA), corrected distance visual acuity (CDVA), adverse device effects (ADEs), and serious adverse events (SAEs).

RESULTS

The study included 1123 implanted eyes (mean age, 37.5 years). At 10 years, mean central and peripheral ECL was 16% (1.7% annualized). Explantations were performed in 10% of eyes (n = 136/1323). For eyes with pIOL explantation because of ECL (7%), annualized ECL rate post-explantation was numerically lower compared with the overall rate in eyes that underwent explantation for any reason (annualized rate, -1.65% vs -2.03%, respectively; n = 96) and compared with pre-explantation ECL. Mean ± SD CDVA and UCVA were -0.12 ± 0.11 and 0.03 ± 0.22 logarithm of the minimum angle of resolution, respectively. Common ocular ADEs included ECL (10%), pIOL extraction (9%), iris adhesion (7%), and pupillary deformity (2%). Common SAEs included pIOL extraction (11%), ECL (9%), and iris adhesions (8%).

CONCLUSIONS

Cachet pIOLs were associated with long-term ECL in some cases. Overall, only 10% of all implanted eyes underwent explantation during 10-year follow-up. In patients requiring explantation because of ECL, the annualized ECL rates decreased post-explantation in some eyes. Continued monitoring of patients regardless of explantation is recommended.

Comparison between Refractive Outcome of Primary Piggyback Intraocular Lens versus Secondary Lens Iris Claw Lens in Posterior Microphthalmos

Purpose

To compare the refractive outcome of 2 different methods of intraocular lens implantation in cases of posterior microphthalmos, primary piggyback IOLs versus secondary iris claw lenses.

Methods

This study was a retrospective interventional comparative study that included 60 eyes of 30 patients. The included patients had bilateral microphthalmos with high axial hyperopia and had undergone a lens-based surgical procedure for hyperopia correction. The included patients were equally divided into two groups. The first group had undergone refractive lens exchange (RLE) with primary piggyback IOL implantation. The second group undergone RLE with maximum available IOL power implanted followed by a secondary implantation of Artisan iris-fixated IOL (Ophtec B.V., Groningen, the Netherlands).

Results

The 2 groups were highly comparable to each other regarding the mean age, axial length (AL), manifest refraction (MR), and K readings. Postoperatively, there was a statistically significant difference between the 2 groups regarding the manifest refraction spherical equivalent (MRSE), mean absolute error (MAE), and uncorrected distance visual acuity (UDVA). There was no significant difference between the 2 groups regarding the CDVA. At 36 months, 20% and 73% of the eyes were within ±0.5 D of intended refraction at 36 months in 1ry piggyback and 2ry Artisan groups, respectively. Fifty-three percent and 93% of the eyes were within ±1.0 D of intended refraction at 36 months in 1ry piggyback and 2ry Artisan groups, respectively (p=0.001).

Conclusion

Secondary procedure with implantation of iris-fixated intraocular lens yielded very good results for treatment of axial hyperopia in cases of posterior microphthalmos. The primary piggyback IOL showed less satisfactory results with cases of under correction and the possible complication of interlenticular opacification. Both groups showed good safety parameters.