Experience with the Artisan phakic intraocular lens in Asian eyes

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

PURPOSE

The purpose of this study was to evaluate long-term corneal endothelial cell changes and visual outcomes after iris-fixated phakic intraocular lens (pIOL) explantation in patients with endothelial damage and to investigate potential predictors of endothelial injury.

METHODS

Consecutive patients undergoing pIOL explantation with corneal endothelial cell density (ECD) <2000 cells/mm 2 at the time of the procedure were retrospectively reviewed in a single tertiary center. All patients were treated between April 2016 and October 2020 at a high-volume referral-based tertiary hospital. The primary outcome was the change in corneal endothelial parameters, including ECD, over long-term follow-up. Secondary outcomes included changes in corrected distance visual acuity and analysis of prognostic factors.

RESULTS

This study included 44 eyes from 28 patients with an average age of 42.5 ± 7.8 years (range: 27-63). Mean ECD before explantation was 1375.4 ± 468.2 cells/mm 2 (range: 622-1996), and the average duration of follow-up after explantation was 20.5 months (6-58.2). Two years after explantation, ECD had significantly decreased by more than 25% to 1019.6 ± 368.6 (608-1689; P < 0.01). However, there was no significant change in corrected distance visual acuity (20/23-20/22, P = 0.59). Longer operation duration (odds ratio, 1.004; P = 0.04) was the only significant factor weakly associated with postoperative decreases in ECD.

CONCLUSIONS

Although ECD continuously decreased despite pIOL explantation on a long-term follow-up, patients did not experience any discomfort or showed decreases in visual acuity. Therefore, a careful follow-up is required for possible endothelial injury after pIOL explantation.

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.

Phakic intraocular lenses: An overview

Phakic intraocular lenses (pIOLs) are a common solution for the surgical correction of high myopia and myopia in thin corneas. Global trends result in increasing rates of patients with high myopia which will result in increased rates of pIOL implantation. Three types of lenses can be distinguished: anterior chamber angle-supported, anterior chamber iris-fixated, and posterior chamber phakic IOLs. The efficacy of phakic intraocular lenses is generally very good, but pIOLs have undergone many changes over the years to improve the safety profile and decrease pIOL-related complications such as endothelial cell loss, corneal decompensation and cataract formation. This article describes the efficacy and safety profiles of the most recent pIOLs, as well as suggests gaps of knowledge that are deserve additional research to optimize the results of pIOLs.

Comparison of surgically induced astigmatism following iris-claw PIOL insertion with scleral, limbal, or corneal incisions

PURPOSE

To compare surgically induced astigmatism (SIA) based on incision site and evaluate the clinical results and astigmatic stability of iris-claw phakic intraocular lens (Artisan lens; Ophtec BV, Groningen, Netherlands) implantation.

METHODS

Eighty-five eyes of 53 patients with myopia who underwent Artisan lens implantation with a 6.2-mm incision and follow-up of 6 months were retrospectively observed. SIA was assessed using keratometric astigmatism at 6 months postoperatively for the incision sites of the sclera, limbus, and cornea, and the efficacy, safety, predictability, and astigmatic stability were also calculated.

RESULTS

SIA obtained using Naeser's polar method (KP[90]SIA) was -0.48 ± 0.35 for scleral incisions, -0.99 ± 0.35 for limbal incisions, and -1.14 ± 0.54 for corneal incisions. Corresponding net astigmatism values, as calculated with KP(90)SIA and KP(135)SIA, were 0.70 ± 0.48 (177°), 1.04 ± 0.37 (175°), and 1.21 ± 0.57 (1°), respectively, with SIA increasing the nearer the incision was to the cornea center. Six months after surgery, the efficacy index was 1.03 and the safety index was 1.08. Ninety-eight percent of patients were within 1.50 diopters of attempted refraction.

CONCLUSIONS

The values of SIA after Artisan lens insertion showed significant differences among three incision locations, despite the absence of significant differences in preoperative steep corneal axis astigmatism values at the incision locations. It would be applicable for refractive surgery in the aspect of minimizing astigmatism after surgery.

Changes in higher-order aberrations after iris-fixated phakic intraocular lens implantation

PURPOSE

To evaluate surgically induced changes in corneal, internal, and ocular higher-order aberrations (HOAs) after phakic intraocular lens (PIOL) implantation and compare them between two PIOLs with different pupillary diameters.

METHODS

Twenty-three eyes with an Artisan PIOL (Ophtec BV, Groningen, The Netherlands) (Artisan group) and 30 eyes with an Artiflex PIOL (Ophtec BV) (Artiflex group) were retrospectively evaluated. The corneal, internal, and ocular HOAs and refractive data were recorded preoperatively and 6 months postoperatively. The root mean squares (RMSs) of the total HOAs from the third- to sixth-order Zernike coefficients were calculated. The RMSs of the third- and fourth-order coefficients represented coma-like aberrations (S3) and spherical-like aberrations (S4), respectively. The main outcome measures were the differences in the parameters among the groups with different pupillary diameters.

RESULTS

The mean postoperative spherical equivalents decreased from -11.84 ± 4.90 to -0.16 ± 0.40 diopters and -9.78 ± 3.20 to -0.09 ± 0.26 diopters in the Artisan and Artiflex groups, respectively. With the 4- and 5-mm pupillary diameters, the postoperative internal and ocular spherical aberrations (Z4(0)) were significantly lower in the Artiflex group than in the Artisan group (4 mm, P = .002, .024; 5 mm, P = .004, .022, respectively). With the 6-mm pupillary diameter, there were no significant postoperative differences in any parameter measured between groups; both groups had positive spherical aberration values.

CONCLUSIONS

The postoperative ocular spherical aberrations were positive after Artisan and Artiflex implantation. The postoperative ocular spherical aberration was greater in the Artisan group, possibly due to differences in the SAs of both PIOLs.

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.

Rigid iris-fixated phakic lens implantation for high myopia: novel trapezoidal corneal versus scleral incisions

PURPOSE

To compare refractive performance of implantation of an iris-fixated phakic intraocular lens (PIOL) through a novel trapezoidal corneal and a scleral tunnel incision.

METHODS

Sixty-nine eyes selected to undergo PIOL implantation were randomly assigned to 1 of 2 groups: 5.2-mm trapezoidal corneal incision (TCI), 34 eyes; 5.2-mm scleral tunnel incision (STI), 35 eyes. Visual acuity, refraction, corneal astigmatism, tonometry, and endothelial cell density were recorded preoperatively and postoperatively. Surgically induced astigmatism (SIA) was calculated using vector analysis.

RESULTS

No intraoperative complications were noted. One day after surgery, the quantity of cells in the anterior chamber was significantly lower in TCI group than in STI group (p=0.019). The percentage of eyes with uncorrected visual acuity (UCVA) of ≥20/25 was 41.2% for TCI and 17.1% for STI; the difference was statistically significant (p=0.03), but not thereafter. The mean corneal astigmatism was significantly lower in the TCI group than in the STI group (p=0.01) 3 months postoperatively and subsequently. No significant between-group difference in SIA was found during the follow-up. There was no significant difference in best-corrected visual acuity and endothelial cell loss between groups, postoperatively.

CONCLUSIONS

The TCI and STI techniques are comparable in terms of safety and induction of astigmatism for the rigid iris-fixated PIOL implantation. However, the TCI is easy to perform and provides a faster visual recovery and lower postoperative corneal astigmatism compared with the STI.

Topography-guided conductive keratoplasty: treatment for advanced keratoconus

PURPOSE

To evaluate the use of topography-guided conductive keratoplasty in eyes with keratoconus.

DESIGN

Interventional case series.

METHODS

We examined 21 eyes in 21 patients with advanced keratoconus. Topography-guided conductive keratoplasty was performed with intraoperative monitoring of corneal astigmatism using a surgical keratometer. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), corneal topography, manifest refraction, intraocular pressure (IOP), corneal endothelial cell counts, complications, and eventual outcomes were evaluated.

RESULTS

UCVA (logarithm of the minimal angle of resolution [logMAR]), which was 1.65 ± 0.49 preoperatively, improved to 1.04 ± 0.64 at 1 week (P < .001) and 1.12 ± 0.61 at 1 month after surgery (P < .001). BSCVA, which was 1.02 ± 0.56 preoperatively, improved to 0.76 ± 0.65 at 1 week (P = .026) and 0.76 ± 0.60 at 1 month after surgery (P = .003). Manifest refraction, which was -15.13 ± 6.66 diopters (D) before surgery, declined to -9.97 ± 6.71 D at 1 month after surgery (P = .002). Although corneal topography reverted to the preoperative pattern and UCVA and BSCVA also regressed toward preoperative values, 12 of 21 eyes were better able to tolerate and conduct normal daily activities using contact lenses. Five subjects have undergone or are considering corneal transplantation after unsatisfactory postoperative results. No serious perioperative complication was observed.

CONCLUSIONS

Topography-guided conductive keratoplasty may be effective in reshaping corneal configuration in eyes with keratoconus, without serious complications, and possibly contributed to avoiding or delaying corneal transplantation.

Factors affecting contrast sensitivity with the Artisan phakic intraocular lens for high myopia

PURPOSE

To evaluate the factors affecting postoperative visual function in eyes with Artisan phakic intraocular lenses (PIOLs).

METHODS

This study examined a retrospective noncomparative case series. Phakic IOLs were implanted in 60 eyes of 36 patients with high myopia. Contrast sensitivity for spatial frequencies of 1.1, 1.7, 2.6, 4.2, 6.6, and 10:4 cycles per degree with and without glare and wavefront aberrations were measured before and 3 months after surgery. The area under the log contrast sensitivity function (AULCSF) was calculated from the contrast sensitivity. Stepwise regression analysis was used to assess the factors that affected the postoperative AULCSF.

RESULTS

No significant difference was noted between the preoperative AULCSF without glare and the postoperative AULCSF without glare (P=.886). The mean AULCSF with glare improved significantly after surgery (P=.018). The variables affecting the postoperative AULCSF without glare were axial length (partial regression coefficient B=-0.101, P=.0002) and age (B=-0.008, P=.0063). The variables affecting the postoperative AULCSF with glare were axial length (B=-0.127, P<.0001) and age (B=-0.012, P=.0294). The preoperative refraction showed multicollinearity with the axial length, and coma-like aberration and spherical aberration showed multicollinearity with age.

CONCLUSIONS

Contrast sensitivity without glare was the same before and after surgery and contrast sensitivity with glare improved after surgery. Longer axial length and older age predispose patients to degradation of the postoperative visual function in eyes with Artisan PIOLs.

Five-Year Outcome of LASIK for Myopia

PURPOSE

To investigate the efficacy and safety of LASIK over a 5-year postoperative period.

DESIGN

Observational case series.

PARTICIPANTS

We examined 779 eyes in 402 patients with myopia or myopic astigmatism who underwent LASIK to correct their refractive errors and received regular postoperative assessments for 5 years.

METHODS

Postoperative examinations were performed 1 day; 1 week; 1, 3, and 6 months; and 1, 2, 3, 4, and 5 years after LASIK surgery.

MAIN OUTCOME MEASURES

We evaluated changes in uncorrected visual acuity (UCVA) (logarithm of the minimum angle of resolution [logMAR]), manifest refraction, best-corrected visual acuity (BCVA) (logMAR), intraocular pressure, corneal thickness, corneal endothelial cell counts, and complications.

RESULTS

Preoperative UCVA of 1.27 improved to -0.03 at 1 day after surgery and -0.08 at 1 month and revealed minimal but significant decreases thereafter. Postoperative manifest refraction was also improved by surgery, showing minimal but significant regression after 1 year. Final BCVA loss was seen in 10 eyes of 7 patients; in 7 cases, there were obvious reasons such as the progression of cataracts in 3 eyes, epithelial disintegrity due to dry eye in 2 eyes, irregular astigmatism due to flap striae in 1 eye, and age-related macular dystrophy in 1 eye. Intraocular pressure and corneal thickness decreased by 4.0 mmHg and 76.9 microm, respectively, due to surgery, but remained stable throughout the follow-up period. Corneal endothelial cell counts (2689.0+/-232.9 cells/mm(2) before surgery) showed a statistically significant decrease at 5 years after surgery (2658.0+/-183.1 cells/mm(2); 1.2% loss for 5 years), likely within the range due to physiological age-related loss. No serious, vision-threatening, irreversible complication such as keratectasia or progressive endothelial cell loss was observed.

CONCLUSION

LASIK surgery is an effective and safe procedure for correcting myopia/myopic astigmatism as long as inclusion and exclusion criteria are strictly respected. However, minimal regression occurred during the 5-year investigative period.

Long-term Follow-up of Endothelial Cell Change after Artisan Phakic Intraocular Lens Implantation

OBJECTIVE

To report endothelial cell densities (ECDs) and their correlation to anterior chamber depth (ACD) after implantation of the Artisan intraocular phakic lens.

DESIGN

Prospective observational case series.

PARTICIPANTS

Three hundred eighteen eyes of 173 myopic patients treated with the Artisan iris-fixated phakic intraocular lens (IOL).

METHODS

Eyes with an ACD ranging between 2.89 and 4.5 mm were implanted with the Artisan phakic IOL. Endothelial cell density measurements were performed preoperatively and at each follow-up examination using a noncontact specular microscope.

MAIN OUTCOME MEASURES

Endothelial cell density (cells per square millimeter).

RESULTS

Follow-up ranged between 1 (82 eyes) and 7 years (13 eyes) (mean, 35.3+/-20.7 [standard deviation] months per eye). After 3 years, there was a significant loss in ECD (P< or =0.03). At 5 years, mean observed endothelial cell loss was 8.3% (5.3% corrected for a natural endothelial cell loss of 0.6% a year). Endothelial cell density loss remained progressive throughout our follow-up period. After 3 years, a significant negative correlation between ACD and endothelial cell loss was revealed (P< or =0.03). Patient age, gender, refractive error, incision size, and side of the eye were not correlated to ECD loss. All corneas remained clear throughout the study.

CONCLUSION

After 3 years, a significant ECD loss was revealed. This ECD loss was significantly negatively correlated to the ACD. We therefore suggest that eyes just meeting the minimum ECD requirement have greater ACDs to compensate for possible greater endothelial cell loss and that patients with shallow anterior chambers have higher ECDs. Artisan phakic lens implantation in young eyes narrowly meeting the minimum criteria of endothelial cell density (2,000 cells/mm(2)) and ACD (2.6 mm) should perhaps be reevaluated, due to longer exposure to higher rates of endothelial cell loss.

Traumatic aniridia and aphakia after Artisan intraocular lens implantation

Traumatic aniridia and aphakia occurred in the left eye of a 22-year-old man who had had Artisan (Ophtec) phakic intraocular lens (IOL) implantation. Aniridia was probably the result of the relatively large wound used to implant the nonfoldable IOL. Although the eye had severe traumatic damage, vision was recoverable through a 2-stage procedure of vitrectomy and subsequent scleral suture fixation of an iris-diaphragm IOL.

Use of Verisyse iris-supported phakic intraocular lens for myopia in keratoconic patients

We report 2 patients with stable keratoconus and high myopia who benefited from implantation of an iris-supported phakic intraocular lens (Verisyse, AMO) for correction of their refractive error. Both patients had a postoperative uncorrected visual acuity of 20/40. Endothelial cell density showed at most a 4% decrease, and no evidence of keratoconus progression was witnessed. The use of the Verisyse lens may be beneficial for certain keratoconic patients as an alternative step between rigid gas-permeable lenses and penetrating keratoplasty.