Iris-fixated Phakic Intraocular Lens Implantation Research Articles

Anterior Chamber Iris-Fixated Phakic Intraocular Lens Implantation for Treatment of High Anisometropia in Children: Long-term Results.

To evaluate the long-term efficacy of anterior chamber iris-fixated phakic intraocular lens (PIOL) implantation in the treatment of high myopic (> -9.00 diopters [D]) or hyperopic (> +6.00 D) anisometropia in children with intolerance to spectacles or contact lenses. A total of 58 children with anisometropic myopia (range: -9.25 to -18.50 diopters [D]) and 13 children with anisometropic hyperopia (range: +6.00 to +8.50 D) underwent unilateral iris-claw PIOL implantation from 2008 to 2018. The mean age was 6.7 years. The mean follow-up was 38.5 months. Target refraction was emmetropia. The cycloplegic refraction (mean spherical equivalent) improved from -12.47 D (range: -9.25 to -18.50 D) to -0.73 D (range: +0.75 to -1.50 D) in myopic eyes and reduced from +7.15 D (range: +6.00 to +8.50 D) to +0.94 D (range: -0.50 to + 1.75 D) in hyperopic eyes. Eighty-four percent of eyes were corrected to within ±1.00 D of emmetropia. The mean uncorrected distance visual acuity (UDVA) improved from 1.74 ± 0.36 to 0.45 ± 0.28 logarithm of the minimum angle of resolution (logMAR) (P = .0014). The mean corrected distance visual acuity (CDVA) changed from 0.68 ± 0.32 to 0.27 ± 0.15 logMAR (P = .02179). The safety index was 2.18 and the efficacy index was 1.51. The mean preoperative endothelial cell count of 2,874.7 cells/mm2 changed to 2,685.3 cells/mm2 at 2 to 6 years postoperatively. Binocular vision quality was improved in 55 patients. No patient had serious complications or lost any Snellen lines of CDVA. Iris-fixated PIOL implantation is an effective and safe method in the treatment of high anisome-tropic myopia and hyperopia and amblyopia in pediatric patients who are noncompliant with spectacles or contact lenses. [J Pediatr Ophthalmol Strabismus. 2023;60(3):203-209.].

Implantation of an iris-fixated phakic intraocular lens for the correction of hyperopia: 15-year follow-up.

To assess the predictability, efficacy, stability, and safety of implantation of an Artisan iris-fixated phakic intraocular lens (IF-pIOL) for the correction of hyperopia with a follow-up of up to 15 years. Leiden University Medical Center, the Netherlands. Patients operated by a single surgeon up to 2007 were identified, and data on refraction, corrected distance visual acuity (CDVA), uncorrected distance visual acuity, endothelial cell (EC) density, and complications were collected. A total of 61 eyes (32 patients) were analysed. The mean spherical equivalent decreased from +6.43 ± 1.78 diopters (D) preimplantation to -0.22 ± 0.57 D at 1 year postimplantation and remained stable throughout follow-up. A stable CDVA with safety indices ranging from 0.91 to 1.10 and efficacy indices between 0.43 and 0.86 were observed. Follow-up time had a significant effect on EC density with an estimated annual decline of 58 cells/mm2 after IF-pIOL implantation. IF-pIOL explantation was performed in a 10 eyes (16.4%) after 8.13 ± 5.11 years. The main reason for IF-pIOL explantation was EC loss (4 eyes [6.6%]). Pigment dispersion was the most encountered complication, observed in 9 eyes (14.8%). Visual and refractive results after implantation of an IF-pIOL to correct hyperopia show favorable and stable results with long-term follow-up. Lifelong monitoring of EC counts is mandatory. Pigment dispersion might be a problem in hyperopic eyes implanted with an IF-pIOL; a shallower anterior chamber depth and a convex iris configuration might be predisposing factors.

Middle- and long-term results after iris-fixated phakic intraocular lens implantation in myopic and hyperopic patients: a meta-analysis.

The iris-fixated phakic intraocular lens (pIOL) has been available for over 25 years. To provide a clear picture of outcomes and risks, for this systematic review and meta-analysis, the literature was searched for reports on middle- and long-term effects. The iris-fixated phakic intraocular lens (pIOL) has been available for over 25 years. To provide a clear picture of outcomes and risks, for this systematic review and meta-analysis, the literature was searched for reports on middle- and long-term effects of iris-fixated pIOLs on myopic and hyperopic eyes with a follow-up of at least 2 to 4 years. Visual and refractive results after implantation for correction of myopia are positive and the complication rate is low. Endothelial cell loss appears to be at an acceptable rate, although the range of endothelial cell change is too wide to draw firm conclusions. Care should be taken when considering an iris-fixated pIOL for hyperopic eyes because complication rates, particularly pigment dispersion, might be higher than those in myopic eyes. More well-designed, long-term studies are needed, especially in hyperopic eyes. The authors advocate for standardized reporting of refractive surgery data. Initiatives proposed by journal authors and editors to achieve uniformity should be supported.

Iris-fixated phakic intraocular lens implantation to correct myopia and a predictive model of endothelial cell loss

To report long-term results of Artisan phakic intraocular lens (pIOL) to correct myopia and to propose a model predicting endothelial cell loss after pIOL implantation. Quinze-Vingts National Ophthalmology Hospital, Paris, France. Retrospective, interventional case series. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and central endothelial cell count (ECC) were determined before and at yearly intervals up to 5 years after pIOL implantation. Linear model analysis was performed to present a model that describes endothelial cell loss as a linear decrease and an additional decrease depending on postoperative loss. A total of 49 patients (68 eyes) implanted with pIOLs from January 2000 to January 2009 were evaluated. The mean preoperative and final spherical equivalent (SE) were -13 ± 4.10 and -0.75 ± 0.74 diopters (D), respectively. The mean preoperative and final central ECC were 2629 ± 366 and 2250 ± 454 cells/mm(2), respectively. There were no intraoperative complications for any of the eyes. One eye required surgery for repositioning the pIOL, and 1 eye required pIOL exchange for postoperative refractive error. The model predicted that for patients with preoperative ECC of 3000, 2500, and 2000 cells/mm(2), a critical ECC of 1500 cells/mm(2) will be reached at 39, 28, and 15 years after implantation, respectively. Implantation of the pIOL was an effective and stable procedure after 5 years of follow-up. The presented model predicted EC loss after pIOL implantation, which can assist ophthalmologists in patient selection and follow-up. The authors report no conflict of interest.

Iris-fixated phakic intraocular lens implantation after retinal detachment surgery: Long-term clinical results

To assess the efficacy and safety of iris-fixated phakic intraocular lens (pIOL) implantation to correct myopia in eyes with previous retinal detachment (RD) surgery. Department of Ophthalmology, Soonchunhyang University College of Medicine, Seoul, South Korea. Retrospective case series. Patients having pIOL implantation in both eyes were enrolled. Eyes that had scleral buckling or encircling (RD group) and healthy fellow eyes (non-RD group) were evaluated over a 6-year follow-up. The corrected distance visual acuity (CDVA), endothelial cell density (ECD), intraoperative complications, and long-term complications were safety outcomes. Uncorrected distance visual acuity (UDVA), predictability, and stability of refraction were efficacy outcomes. The study comprised 34 eyes (17 patients). The mean postoperative CDVA and ECD were not significantly different between groups, and no patient lost CDVA. The rate of transient intraocular pressure spike was significantly higher in the RD group (P=.043). After 3 years and 6 years, the mean postoperative UDVA was 0.06 logMAR ± 0.09 (SD) and 0.08 ± 0.10 logMAR, respectively, in the RD group and 0.04 ± 0.08 logMAR and 0.04 ± 0.09 logMAR, respectively, in the non-RD group (P=.518 and P=.478, respectively). The rate of eyes within ±0.50 diopter of the desired refraction and the postoperative refraction was not significantly different between groups. No eye had vitreoretinal changes requiring secondary surgical intervention. Iris-fixated pIOL implantation corrected the myopic refractive error in patients who had scleral buckling or encircling surgery for RD with a high degree of efficacy, safety, and long-term stability. No author has a financial or proprietary interest in any material or method mentioned.

Evaluation of sterile uveitis after iris-fixated phakic intraocular lens implantation

Purpose:To evaluate the clinical features, and visual outcomes of sterile uveitis after iris-fixated phakic intraocular lens implantation (pIOLs) (Artisan-Artiflex® and Verisyse-Veriflex®).Material and Methods:In this retrospective non-comparative case series, the medical records of 117 eyes implanted with Artisan-Artiflex® (Ophtec BV, Groningen, Netherlands) and Verisyse-Veriflex® (AMO, Santa Ana, CA) iris claw phakic IOLs were analyzed for postimplantation sterile uveitis. The mean age of the 87 patients included in the study was 27.2±7.4 years. Of these patients, 56 (64.3%) were men and 31 (35.6%) were women. Patient age, gender, IOL brand type, refractive error, optic diameter, unilateral vs bilateral implantation, and anterior chamber depth were analyzed. Features of uveitis, uncorrected and best corrected visual acuity (VA) at presentation and at follow-up visits were examined. The mean follow-up time was 14.6 months (range: 6-37 months).Results:Clinically significant uveitis was observed in 12 of 117 eyes (10.3%) in a total of ten patients. Of these ten patients, four (40%) were women and six (60%) were men, and the mean age was 25.1±5.3 years (range: 18-36 years). Among those with bilateral implantation, 6.9% of patients developed bilateral uveitis, while 13.8% (4 of the 29 implanted bilaterally) developed unilateral uveitis. Foldable pIOL implantation was the only variable associated with the development of uveitis (P=.03).Conclusion:Although the prognosis is usually benign, sterile uveitis occurred in 10.3% of patients after iris-fixated pIOL implantation. The implantation of a foldable pIOL was the only variable associated with sterile uveitis. Appropriate medical management can be effective treatment, without the need for pIOL replacement.

The Effect of Iris-Fixated Foldable Phakic Intraocular Lenses on Retinal Straylight

To determine changes in straylight after iris-fixated phakic intraocular lens implantation (pIOL) and to investigate the relationship between straylight and several preoperative and postoperative variables. Institutional, prospective cross-sectional study. Artiflex (Ophtec B.V.) pIOL implantation was performed in 61 eyes (36 patients). Straylight values were measured before surgery and 3 months after surgery using the Oculus C-Quant (Oculus Optikgeräte). Furthermore, correlations were analyzed between straylight and the following parameters: keratometry, axial length, spherical equivalent, astigmatism, pIOL power, best spectacle-corrected visual acuity, and pupil size. Mean straylight decreased from 1.18 ± 0.17 log units before surgery to 1.13 ± 0.17 after surgery (P = .016). Higher preoperative straylight values were associated with larger postoperative decreases in straylight (r = -0.534; P < .001). Higher postoperative straylight values were correlated to higher axial length (r = 0.444; P = .001) and lower keratometry values in diopters (r = -0.414; P = .001). After regression analysis, only axial length was found to be an independent predictor of preoperative and postoperative straylight (P < .001 and P = .001, respectively). After correcting for the axial length of an emmetropic eye (23.44 mm), all straylight correlations disappeared, indicating that an increase in distance from cornea to retina explains the increase in straylight values in longer eyes. Retinal straylight was reduced significantly after Artiflex pIOL implantation. Besides age, axial length was the only predictor of preoperative and postoperative straylight values. The increased tissue length light has to pass from cornea to retina, might explain the increase in straylight values in longer eyes.

Comparison of wavefront-guided photorefractive keratectomy and foldable iris-fixated phakic intraocular lens implantation for low to moderate myopia

To compare and evaluate the visual and refractive outcomes of myopic wavefront-guided photorefractive keratectomy (PRK) and foldable phakic intraocular lens (pIOL) implantation for myopia. Department of Ophthalmology, Haaglanden Medical Center, The Hague, The Netherlands. Comparative case series. The differences in visual acuity and residual refractive outcomes after wavefront-guided PRK and Artiflex foldable pIOL implantation were compared in eyes with low to moderate myopia (spherical error -4.0 to -7.0 diopters [D]; maximum cylinder 2.25 D). One-year follow-up results are presented. At 1 year postoperatively, the mean decimal Snellen uncorrected distance visual acuity was 1.05 ± 0.21 (SD) in the PRK group (60 eyes) and 1.04 ± 0.21 in the pIOL group (33 eyes) and the mean corrected distance visual acuity (CDVA), 1.21 ± 0.18 and 1.24 ± 0.13, respectively. In the PRK group, 21.7% of eyes lost 1 to 3 lines of CDVA and 11.7% of eyes gained 1 or 2 lines. In the pIOL group, no eye lost lines of CDVA and 42% gained 1 or 2 lines. At 1 year, 80.0% of eyes in the PRK group and 90.9% of eyes in the pIOL group were within ± 0.50 D of the spherical equivalent. There were no statistically significant differences in safety and efficacy between the pIOL group and the PRK group at 1 year. However, the percentage of eyes that gained lines of CDVA was significantly higher in the pIOL group.

Change of accommodative function in phakic eyes with iris-fixated phakic intraocular lens implantation

To evaluate the changes of accommodative function after implantation of iris-fixated phakic intraocular lens (IFPIOL) for correction of high myopia, and compared with gender and age matched emmetropes. This study also provides clinical basis for assessing the quality of life after implantation of the IFPIOL. It was a case-control study. Iris-fixated in phakic intraocular lens implantation was performed in 23 eyes of 12 high myopic patients. Control group included 22 eyes in 11 emmetropes. All patients and controlled subjects had the same examinations including amplitude of accommodation, accommodative facility test, and negative/positive relative accommodation before, 1 month and 3 months after operation. Surgery was performed by the same surgeon. Randomized block design analysis of variance was applied to analyze accommodative function between the patients preoperative and postoperative, and two independent samples t-test was applied to analyze accommodative function between the control group and the patients. P value less than 0.05 was considered significant. The mean amplitude of accommodation at 1 month and 3 months was (8.90 ± 2.13) D and (9.10 ± 1.72) D after IFPIOL implantation, respectively. Mean amplitude of accommodation after the operation was significantly greater than that from preoperative eyes (7.35 ± 2.20) D, (F = 19.88, P < 0.01). Mean amplitude of accommodation at 3 months in eyes after IFPIOL implantation showed no significant difference (t = -1.76, P = 0.09) as compared with the control group (10.10 ± 2.09) D. Mean accommodative facility at 1 month and 3 months after IFPIOL implantation was (8.17 ± 2.09) cyc/min and (8.67 ± 1.80) cyc/min, respectively. This was significantly increased from preoperative data which was (5.67 ± 1.53) cyc/min, (F = 64.27, P < 0.01). Mean accommodative facility at 3 months after IFPIOL implantation had no statistically significant difference (t = -6.29, P < 0.01) as compared with the control group (14.51 ± 3.81) cyc/min. In addition, mean positive relative accommodation (2.45 ± 0.81) D was significantly greater than that in preoperative eyes (1.61 ± 0.80) D, (F = 6.10, P = 0.01) but, not significantly different (t = -2.83, P = 0.01) from the control group (3.89 ± 1.49) D. Patients can obtain physiological accommodative function after the implantation of IFPIOL for correction of high myopia. Moreover, the accommodative function increases with time and is stable. Nevertheless, accommodative function could not reach the level of normal emmetropic eyes. Longer-term results would be further observed.

Iris-fixated phakic intraocular lens implantation for correction of high myopia in microspherophakia

We report the refractive correction of high myopia in a 23-year-old patient with idiopathic microspherophakia using iris-fixated phakic intraocular lenses (pIOLs) (Verisyse/Artisan). Four years after bilateral implantation, the uncorrected distance visual acuity was 20/25 with a correction of 20/20(-1) in both eyes. No intraoperative or postoperative complications occurred. Iris-fixated pIOLs are not recommended for every patient with microspherophakia. However, this procedure may be an option in microspherophakic patients with appropriate anterior chamber depth and no history of lens dislocation who are likely to comply with annual eye examinations. Follow-up should include monitoring the endothelial cell count and biomicroscopy for adequate space between the pIOL, the natural crystalline lens, and the corneal endothelium. Scheimpflug photography can be a valuable tool in such cases.

Endothelial Cell Loss After Toric Iris-fixated Phakic Intraocular Lens Implantation: Three-year Follow-up

To study quantitative changes in endothelial cell count after implantation of the toric iris-fixated phakic intraocular lens. A prospective, non-randomized, self-controlled clinical trial was conducted of 40 eyes (28 myopic, 12 hyperopic) of 23 patients with high ametropia and astigmatism. Non-contact computer-assisted endothelial microscopy was performed before and 1, 2, and 3 years after surgery. In the myopic group, mean preoperative endothelial cell count was 3179 +/- 531 cells/mm2 (range: 1800 to 3900 cells/mm2). The mean intra-individual endothelial cell loss was -1.83 +/- 2.25% (range: -9.09% to 0%) in the first year; -1.83 +/- 2.95% (range: -7.74% to 3.80%) in the second year; and -3.20 +/- 4.43% (range: -14.25% to 1.91%) three years after surgery, compared to preoperative values. In the hyperopic group, mean preoperative endothelial cell count was 3107 +/- 125 cells/mm2 (range: 2932 to 3300 cells/mm2). The mean endothelial cell loss was -1.63 +/- 1.76% (range: -3.23% to 1.67%) in the first year; -0.05 +/- 1.25% (range: -1.65% to 1.75%) in the second year; and -2.88 +/- 2.03% (range: -5.33% to -0.13%) three years after surgery, compared to preoperative values. Annual cumulative cell loss was -1.9% for the myopic group and -1.6% for the hyperopic group, which is two to three times greater than physiological annual cell loss in normal eyes without surgery. An annual endothelial cell count analysis is highly recommended in every patient after iris-claw lens implantation to detect potential progressive cell loss at an early stage.