Long-term Results of Correction of High Myopia With an Iris Claw Phakic Intraocular Lens

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.

Surgical management of aphakia

Despite the safety and efficacy of cataract surgery, intraoperative complications can hamper the ability to place an intraocular lens in the capsular bag. With vast numbers of cataract surgeries performed daily, complications occur often enough that every ophthalmologist should be equipped with techniques to manage aphakia. Medical management of aphakia used to be commonplace but these techniques have their disadvantages including thick bulky lenses, poor cosmesis, and aniseikonia. Surgical management of aphakia overcomes these disadvantages and offers patients the possibility of a spectacle and contact lens-free lifestyle. This article reviews the various options of surgical management of aphakia and their advantages and disadvantages. Comparison of outcomes between techniques and a protocol for deciding between techniques is presented.

Iris-Claw Intraocular Lens: Anterior Chamber or Retropupillary Implantation? A Systematic Review and Meta-Analysis

Background and Objectives: Iris-claw intraocular lens (ICIOL) could be implanted in the anterior chamber (AC) or retropupillary (RP) in eyes lacking capsular and/or zonular support. Several studies have focused on comparing the efficacy and complications of these two techniques and we designed this research to review the published literatures. Materials and Methods: Peer-reviewed studies were collected through network databases (PubMed, Scopus, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov) and analyzed. The primary outcome was the standardized mean differences (SMDs) of pre- and post-operative corrected distant visual acuity (CDVA). The secondary outcome was the SMDs of pre- and post-operative intraocular pressure (IOP), endothelial cell counts (ECC), and the odds ratios (ORs) of post-operative IOP elevation and cystoid macular edema (CME). Comprehensive Meta-Analysis software was utilized to conduct statistical analysis. Results: Six studies (one randomized controlled trial and five retrospective case series) were relevant and included a total of 516 eyes (255 and 261 eyes in the AC ICIOL and RP ICIOL groups, respectively). The quantitative analysis showed no significant differences in CDVA (SMD: 0.164, 95% confidence interval (CI): -0.171 to 0.500), ECC (SMD: -0.011, 95% CI: -0.195 to 0.173), and IOP elevation events (OR: 0.797, 95% CI: 0.459 to 1.383). Lesser IOP reduction (SMD: 0.257, 95%CI: 0.023 to 0.490) and a relative increase in the incidence of CME (OR:2.315, 95% CI: 0.950 to 5.637) were observed in the AC ICIOL group compared with RP ICIOL group. Conclusions: Our meta-analysis indicated that AC and RP ICIOL seem to have equivalent visual outcomes. RP ICIOL may perform slightly better with more IOP reduction and lesser CME. More randomized controlled trials, which have higher patient participation and more outcomes are needed to confirm our conclusions.

Dependency of endothelial cell loss on anterior chamber depth within first 4 years after implantation of iris-supported phakic intraocular lenses to treat high myopia

PURPOSE

To evaluate the effect of the anterior chamber depth (ACD) on the central corneal endothelial cell density (ECD) in eyes after implantation of an iris-fixated phakic intraocular lens (pIOL).

SETTING

Department of Ophthalmology, Goethe-University, Frankfurt, Germany.

DESIGN

Retrospective nonrandomized case series.

METHODS

An Artisan pIOL was implanted in eyes of highly myopic patients. Follow-up examinations at 1, 12, 24, 36, and 48 months included evaluation of ECD and adverse events. Three cohorts based on the ACD were established and their ECDs compared. All eyes had 1-year and 4-year postoperative ECD measurements available. Statistical analysis included linear regression analysis to evaluate the influence of ACD on ECD.

RESULTS

The study comprised 95 eyes (52 patients). Four years after surgery the mean spherical equivalent changed from -11.06 diopters (D) ± 4.77 (SD) to -0.42 ± 0.47 D. Severe adverse events were not detected. There was a significantly higher ECD loss after 4 years in patients with an ACD of less than 3.00 mm than in those with an ACD greater than 3.40 mm (-224 cells/mm²) (P < .01). There was no significant difference in ECD between eyes with an ACD of 3.00 to 3.39 mm and eyes with an ACD less than 3.00 mm (P = .23) or more than 3.40 mm (P = .08).

CONCLUSIONS

The iris-claw pIOL precisely and safely corrected high myopia. However, the loss in ECD can be considerable. Establishing stricter exclusion criteria for ACD might reduce this loss.

FINANCIAL DISCLOSURE

Proprietary or commercial disclosures are listed after the references.

An angle-supported foldable phakic intraocular lens for correction of myopia: A five-year follow-up

OBJECTIVE

To evaluate the efficacy and safety of an angle-supported foldable phakic intraocular lens (pIOL) for the correction of moderate to high myopia after 5 years follow-up.

METHODS

Prospective and retrospective, observational, longitudinal, non-randomised consecutive series of cases conducted on a total of 100 eyes of 67 patients with moderate to high myopia implanted with an Acrysof Cachet pIOL (Alcon Laboratories Inc.) with the aim of minimising the refractive error. The ages ranged between 18 to 60years. Uncorrected distance visual acuity (UDVA), manifest refraction, corrected distance visual acuity (CDVA), endothelial cells density, pIOL position, intraocular pressure, and complications were recorded preoperatively and during the 5 year follow-up.

RESULTS

Five years after implantation, the mean manifest spherical equivalent refraction reduced significantly from -11.62±3.35 dioptres (D) to -0.33±0.85D. UDVA was 20/20 or better in 5 of 25 cases (20%), and 20/40 or better in 22 cases (88%). CDVA was 20/20 or better in 17 cases (68%), and 20/32 or better in 23 cases (92%) of eyes. The residual refractive error was within ±0.50D of emmetropia in 12 cases (48%), and within ±1.00D in 19 cases (76%). Mean endothelial cell loss at 5 years was 11.8% central, and 13.7% peripheral. Mean endothelium-pIOL distance was 2.11±0.18mm, and mean pIOL-crystalline distance was 0.88±0.20mm.

CONCLUSIONS

This angle supported pIOL provided a favourable refractive correction and predictability, as well as acceptable safety in patients with moderate to high myopia. Although endothelial cell density decreased over 5years, the results are within the range reported in previous studies with other pIOLs.

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

PURPOSE

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.

SETTING

Department of Ophthalmology, Soonchunhyang University College of Medicine, Seoul, South Korea.

DESIGN

Retrospective case series.

METHODS

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.

RESULTS

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.

CONCLUSION

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.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Refractive lens exchange versus phakic intraocular lenses

PURPOSE OF REVIEW

To review the evidential basis of current practice in refractive lens exchange (RLE) vs. phakic intraocular lens (pIOL).

RECENT FINDINGS

Visual outcomes after pIOLs are better than RLE. With RLE, there still remain risks of retinal detachment, cystoid macular oedema, glare, halos and posterior capsule opacification. With pIOLs, risks include pigment dispersion, cataract formation, glaucoma and inflammation. The decision to choose between either is broadly based on age and type of refractive error, and the choice follows thorough evaluation and counselling taking into consideration patient's needs and expectations.

SUMMARY

With advancing technology, newer IOL models for RLE and phakic correction are becoming available. pIOLs provide better visual outcomes for distance correction and currently do not provide near-vision correction possible with RLE.

Five-year follow-up after anterior iris-fixated intraocular lens implantation in phakic eyes to correct high myopia

PURPOSE

To evaluate the 5-year follow-up of safety, efficacy, predictability, stability, and complications of anterior iris-fixated phakic intraocular lens (pIOL) implantation to correct high myopia, and patients' satisfaction after implantation.

DESIGN

Prospective, nonrandomized, and comparative (self-controlled) trial.

METHODS

A prospective clinical trial of 84 eyes of 43 patients with high myopia was conducted. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, endothelial cell count, intraocular pressure (IOP), anterior chamber depth, slit lamp biomicroscopy, and indirect ophthalmoscope were measured preoperatively and postoperatively.

RESULTS

At the 5-year follow-up, UCVA was significantly improved, with 85.7% of eyes reaching 20/25 or better. No eyes experienced a loss in BSCVA, and 71.4% gained one or more lines of their preoperative BSCVA. There was a significant reduction in spherical errors in all patients after operation. Loss of endothelial cells was observed 3 years after operation and no more loss was observed 4 years after operation in statistical analysis. No increase in IOP was observed 5 years after operation in statistical analysis. No intraoperative complications were observed in this study. However, pigment precipitates of varying intensities on the lens optic were noted in all patients 1 day after operation, and only five eyes were observed to have the pigment residual five years after operation.

CONCLUSION

At the 5-year follow-up, the implantation of the anterior iris-fixated pIOL was proved to be effective, predictable and capable of reversibility to correct high myopia in phakic eyes. It was a safety addition to the laser refractive surgery. However, longer follow-up with larger numbers of patients is still necessary to evaluate long-term complications.

Current approaches for management of postpenetrating keratoplasty astigmatism

A successful corneal graft requires both clarity and an acceptable refraction. A clear corneal graft may be an optical failure if high astigmatism limits visual acuity. Intraoperative measures to reduce postkeratoplasty astigmatism include round and central trephination of cornea with an adequate size, appropriate sutures with evenly distributed tension, and perfect graft-host apposition. Suture manipulation has been described for minimising early postoperative astigmatism. If significant astigmatism remains after suture removal, which cannot be corrected by optical means, then further surgical procedures containing relaxing incisions, compression sutures, laser refractive surgery, insertion of intrastromal corneal ring segments, wedge resection, and toric intraocular lens implantation can be performed. When astigmatism cannot be reduced using one or more abovementioned approaches, repeat penetrating keratoplasty should inevitably be considered. However, none of these techniques has emerged as an ideal one, and corneal surgeons may require combining two or more approaches to exploit the maximum advantages.

Artiflex phakic intraocular lens implantation after corneal collagen cross-linking in keratoconic eyes

PURPOSE

To evaluate the safety, efficacy, and stability of the Artiflex (Ophtec BV) foldable anterior iris-claw phakic intraocular lens (PIOL) following corneal collagen cross-linking (CXL) in select cases of progressive keratoconus.

METHODS

This prospective, comparative study, conducted between March 2007 and June 2008, involved 11 eyes with progressive keratoconus. Inclusion criteria were progressive keratoconus (Amsler-Krumeich classification grades I and II) with no corneal opacities, corneal thickness >450 μm, endothelial cell count >2500 cells/mm(2), anterior chamber depth >3.2 mm, spherical equivalent refraction >4.50 diopters (D) (with a cylinder component <2.00 D), and no other treatment for keratoconus other than contact lens. Each patient underwent CXL in the keratoconic eye with implantation of the Artiflex IOL 6 months thereafter. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and refraction and topographic profiles were examined at 1, 6, and 12 months after the CXL procedure.

RESULTS

All eyes achieved UDVA of 0.3 logMAR or better. Final spherical and cylindrical error ranged from 0 to -1.50 D and 0 to -1.75 D, respectively. No eyes lost lines of preoperative CDVA. Statistically significant reductions in mean maximum (2.14 D, P<.001) and minimum (1.17 D, P=.02) keratometry values were present 12 months after the CXL procedure. No complications were observed.

CONCLUSIONS

Combined CXL and Artiflex implantation was a safe and effective treatment in this subset of eyes with progressive keratoconus. Good results in terms of visual acuity, postoperative residual refractive error, and keratometry values were identified.

Visual outcomes following Artisan aphakia iris claw lens implantation

OBJECTIVE

To assess the visual outcome of eyes undergoing Artisan lens implantation for aphakia, to identify reasons for poor outcomes, and to report incidences of post-operative uveitis, glaucoma, or hyphaema.

METHODS

A retrospective analysis of 32 eyes rendered aphakic through various causes, which subsequently underwent Artisan lens implantation.

RESULTS

A total of 32 eyes from 31 patients were reviewed. Follow-up ranged from 6 to 42 months, mean 17.3 months. The commonest cause of aphakia was following complicated phacoemulsification in 17 of the 32 eyes (53.1%). At final follow-up, 21 of the 32 eyes (65.6%) achieved best-corrected visual acuity (BCVA) better than that measured pre-operatively and 10 of the 32 eyes (31.3%) matched their pre-operative BCVA. Of 33 eyes, only 1 (0.03%) attained a final BCVA worse than pre-operatively, owing to non-arteritic anterior ischaemic optic neuropathy. A total of 4 of the 33 eyes (12.5%) had pre-existing glaucoma or ocular hypertension; no additional intraocular pressure problems were identified during the follow-up period.

CONCLUSION

This study suggests that Artisan iris claw lens insertion is beneficial in acquired aphakia, matching or exceeding pre-operative BCVA in the overwhelming majority of the cases. In addition, this series did not identify any post-operative problems with uveitis, glaucoma, or hyphaema.

Retinal complications of phakic intraocular lenses

High myopia has always been a challenge for refractive correction. Current laser surgical techniques, however, fall short of correcting high refractive errors due to lack of predictability, regression, corneal ectasia, and introduction of high order optical aberration. Phakic intraocular lenses (IOL) have been proposed as an effective refractive surgical procedure for the correction of severe myopia, but, despite recent advances in implant material technology and design, their concept is still under clinical investigation. Most of the concern regarding the complications of phakic IOLs focuses on the anterior segment of the eye. This review examines the posterior segment complications associated with phakic IOL implantation, evaluates possible pathogenetic mechanisms and discusses posterior segment complications, prevention and management.

[Iris-fixated intraocular lenses: reinforced monitoring]

In 1986, the concept of the claw lens was applied to correct myopia in phakic patients. Since then, progress has made iris-fixated phakic intraocular lenses (IOL) relatively safe, predictable, and effective for the correction of myopia, hyperopia, and astigmatism. All these models have undergone a series of design improvements to prevent complications. Despite having excellent refractive results, the principal risk is a potential progressive endothelial cell loss. Many authors have presented encouraging results. Phakic iris-fixated IOL surgery is a potentially reversible procedure, but the surgeon cannot rule out the possibility of complications. Therefore, long-term follow-up is mandatory.

Higher-order aberrations after implantation of iris-fixated rigid or foldable phakic intraocular lenses

PURPOSE

To evaluate higher-order aberrations (HOAs) after implantation of Artiflex phakic intraocular lenses (pIOLs).

SETTING

Department of Ophthalmology, Academic Hospital Maastricht, Maastricht, The Netherlands.

METHODS

This retrospective comparative case series comprised 27 eyes (14 patients) that had Artiflex pIOL implantation and 22 eyes (13 patients) that had Artisan pIOL implantation. Refractive data, pupil size, IOL decentration, and HOA values were recorded and compared. Laboratory analysis was performed. Follow-up was 1 year.

RESULTS

In the Artiflex group, the mean spherical equivalent (SE) changed from -9.95 diopters (D) +/- 1.43 (SD) (range -6.75 to -12.13 D) to -0.30 +/- 0.53 D (range -1.94 to 0.56 D). Postoperatively, trefoil-y increased (increase factor 1.73) and spherical aberration decreased (increase factor 0.55). The mean pIOL decentration was 0.24 +/- 0.12 mm; 96.3% were decentered 0.5 mm or less. There was a significant correlation between pIOL decentration and postoperative spherical aberration and coma-y. In the Artisan group, the mean SE changed from -9.90 +/- 2.74 D (range -4.00 to -14.50 D) to -0.20 +/- 0.42 D (range -0.75 to 0.50 D). Postoperatively, trefoil-y and spherical aberration increased (increase factors 3.32 and 6.84, respectively). Laboratory analysis confirmed the negative and positive spherical aberration profile of the Artiflex pIOL and Artisan pIOL, respectively.

CONCLUSIONS

Artiflex pIOL implantation decreased spherical aberration, while Artisan pIOL implantation increased spherical aberration. Trefoil-y increased in both groups. These changes might be explained by incision size differences in relation to trefoil and differences in optic design in relation to spherical aberration.

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.

Basic knowledge of refractive surgery: correction of refractive errors using modern surgical procedures

INTRODUCTION

Refractive ophthalmic surgery allows refractive errors to be corrected permanently in a safe, effective, and reliable way with few complications.

METHODS

Selective literature review with special reference to the guidelines of the German Commission for Refractive Surgery.

RESULTS

With a total of almost 18 million treatments performed to date, laser in-situ keratomileusis (LASIK) is the most commonly used refractive surgical procedure worldwide. Alternatives to LASIK include surface ablation procedures (PRK, LASEK, Epi-LASIK) and phakic intraocular lens implantation. If ocular accommodation is lost, removal of the crystalline lens and implantation of modern multifocal intraocular lenses (refractive lens exchange) provide an alternative means of correcting myopia, hyperopia and presbyopia.

DISCUSSION

The treatment effect is maximized and complications kept to a minimum if strict inclusion criteria are applied and a high technical standard maintained during the procedure.

Long-term endothelial changes in phakic eyes after Artisan intraocular lens implantation to correct myopia: five-year study

PURPOSE

To evaluate long-term endothelial cell changes in eyes that had implantation of an iris-fixated phakic Artisan intraocular lens (IOL) for moderate to high myopia.

SETTING

Casa di Cura Villa Igea, Ancona, Italy.

METHODS

Forty-nine eyes of 30 patients having implantation of Artisan IOL for moderate to high myopia were prospectively examined. Preoperative specular microscopy and serial postoperative specular microscopy (Noncon Robo SP 8000, Konan Medical) were performed to evaluate endothelial cell changes over 5 years. Endothelial cell images were collected in the central region of the cornea before surgery and 4, 12, 24, 36, 48, and 60 months after surgery. The endothelial cell density (ECD), coefficient of variation, and percentage of hexagonal cells were determined.

RESULTS

Preoperatively, the mean ECD was 2616 cells/mm(2) +/- 347 (SD), the mean coefficient of variation was 39.6% +/- 4.7%, and the mean percentage of hexagonal cells was 49.2% +/- 6.7%. The mean endothelial cell loss from preoperatively was 2.3% at 4 months, 3.5% at 12 months, 4.7% at 24 months, 6.7% at 3 years, 8.3% at 4 years, and 9.0% at 5 years. Five years after surgery, the mean coefficient of variation was 35.9% +/- 6.9% (P = .1946) and the percentage of hexagonal cells was significantly higher (mean 54.7% +/- 10.3%) (P = .087).

CONCLUSIONS

Continuous endothelial cell loss was observed after surgery during a 5-year follow-up, especially during the first 2 years. A decrease in the coefficient of variation and an increase in the percentage of hexagonal cells were observed over time, reflecting the increasing stability and remodeling of the corneal endothelial cells 5 years postoperatively.

Comparison of Anterior Chamber Depth Measurement Between Orbscan IIz and Ultrasound Biomicroscopy

PURPOSE

To compare the measurement of anterior chamber depth exclusive of corneal thickness using Orbscan IIz and ultrasound biomicroscopy (UBM) and evaluate the repeatability of each method.

METHODS

Three consecutive measurements of anterior chamber depth were prospectively performed using Orbscan IIz and Paradigm 50-MHz UBM in 40 eyes in 20 individuals. Mean values were compared using the paired t test. For 12 eyes in 6 individuals, anterior chamber depth measurements were performed 5 times to estimate the repeatability of each method by a coefficient of variation. Refractive errors were measured to correlate with anterior chamber depth.

RESULTS

The mean anterior chamber depth was 2.82 +/- 0.46 mm with the Orbscan IIz and 2.91 +/- 0.43 mm in UBM. This difference was statistically significant (P < .001), but not clinically meaningful. The coefficient of variation was 1.15% and 1.10% in Orbscan IIz and UBM, respectively. A negative correlation between anterior chamber depth and spherical equivalent refraction was noted within the range of -5.50 to +3.00 diopters.

CONCLUSIONS

The mean anterior chamber depth of Orbscan IIz was 0.087 mm less than that of UBM. Both methods were precise. Orbscan IIz seems to be a useful and more convenient method to measure anterior chamber depth for phakic intraocular lens implantation.

Changes in Higher Order Aberrations and Contrast Sensitivity after Implantation of a Phakic Artisan Intraocular Lens

PURPOSE

To evaluate higher-order aberrations (HOAs) and contrast sensitivity (CS), and investigate their relationship, after implantation of a phakic Artisan intraocular lens (IOL) for high myopia.

METHODS

A prospective study including 25 eyes of 15 patients with high myopia (greater than -8.00 D) who underwent phakic Artisan IOL implantation was carried out. Uncorrected visual acuity (UCVA), best corrected visual acuity, manifest refraction, and pupil diameter were measured at baseline and at 1 and 3 months postoperatively. HOAs were measured by Wavescan(R) (VISX Inc., Santa Clara, Calif., USA) from the 3.0 mm pupil entrance, and CS was measured using the VCTS(R) 6500 (Vistech consultants, Inc., Dayton, Ohio, USA) under photopic conditions. The area under the log contrast sensitivity function (AULCSF), defined as the integration of the fitted third order polynomial of the log CS units between the fixed limits of 0.18 (1.5 CPD) and 1.25 (18 CPD) on the log spatial frequency scale, was calculated.

RESULTS

UCVA LogMAR improved from 1.58 at baseline to 0.22 at 3 months, and spherical equivalent refraction was -0.77 +/- 0.34 D at 3 months. The total HOAs had increased slightly at 1 month. CS had decreased significantly at all cycles per degree (p < 0.05) at 1 month, but returned to baseline values at 3 months. Postoperative AULCSF did not correlate with total HOAs under photopic conditions, but correlated with UCVA LogMAR at 1 month (p = 0.037).

CONCLUSIONS

Phakic Artisan IOL implantation for the correction of high myopia resulted in a small increase of HOAs under photopic conditions. At 1 month, CS was decreased, but returned to baseline at 3 months under photopic conditions. Postoperative AULCSF did not correlate with total HOAs at 1 month.

Position of myopic iris-claw phakic intraocular lens by Scheimpflug photography and ultrasound biomicroscopy

PURPOSE

To evaluate the position of iris-claw phakic intraocular lens (ICPIOL) in highly myopic eyes by Scheimpflug photography (SP) and ultrasound biomicroscopy (UBM).

METHODS

Nine eyes of five patients aged 31+/-10 years with average spherical equivalent of -16.04+/-5.46 D (range -7.88 to - 22.88 D) were enrolled in this prospective study and implanted with Verisyse ICPIOLs (AMO). The anterior segment was evaluated by SP and UBM preoperatively and for at least 1 month postoperatively. The statistical significance may be questionable due to the limited number (nine) of eyes.

RESULTS

By SP and UBM, the distance between corneal endothelium and lens (anterior chamber depth) preoperatively was 3.10+/-0.14 and 3.07+/-0.11 mm, respectively; between ICPIOL and corneal endothelium (pseudo-anterior chamber depth), 1.88+/-0.09 and 1.99+/-0.12 mm, respectively; between lens and posterior surface of ICPIOL (IL), 0.76+/-0.13 and 0.67+/-0.06 mm, respectively; between superior optic edge and iris (SOEI), 0.23+/-0.23 and 0.58+/-0.24 mm, respectively; between inferior optic edge and iris (IOEI), 0.07+/-0.13 and 0.41+/-0.22 mm, respectively; between ICPIOL haptics and the angle of anterior chamber (HA), 0.90+/-0.17 and 1.45+/-0.13 mm, respectively. ACD was well correlated between the two methods, but PACD, IL, OEI, HA were not. The postoperative measures, except IL, were significantly different between the two methods.

CONCLUSION

The differences between measurements by SP and UBM reveal the ICPIOL's position variations with change of body position. Nevertheless, it seems adequate that space is maintained between ICPIOL and corneal endothelium, angle, and crystalline lens. The ICPIOL implanted in phakic eyes seems a safe alternative for treatment of high myopia.

[Long-term changes in pupil size after implantation of an Artisan phakic intraocular lens for correction of high myopia]

PURPOSE

To evaluate the long-term changes in pupil size after implantation of an Artisan phakic intraocular lens for correction of high myopia.

PATIENTS AND METHODS

Fourteen myopic eyes of seven patients were included in the study. Pupil size was measured under photopic conditions, under scotopic conditions after 10 min of dark adaptation, and after topical medical mydriasis. The pupil size was measured using the eye image of the OPD scan (Nidek).

RESULTS

The mean follow-up was 46 months after surgery. The mean photopic pupil diameter was 2.94+/-0.33 mm (range, 2.54-3.6 mm). The diameter of the scotopic pupil remained less than 6.0 mm in all patients (4.68+/-0.59 mm, with maximal pupil diameter of 5.67 mm). The mean pupil diameter after pharmacological dilation was also reduced (5.39+/-1.08 mm; range, 4.19-7.59 mm), with pupil dilation more than 7 mm in only one patient.

CONCLUSION

The iris-fixated intraocular lens mechanically limited pupil dilation in our patients. The long-term reduction in pupil size after Artisan phakic intraocular lens implantation may contribute to the maintenance of the quality of vision in scotopic conditions.

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

PURPOSE

To study quantitative changes in endothelial cell count after implantation of the toric iris-fixated phakic intraocular lens.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Long-Term Follow-Up of the Corneal Endothelium After Artisan Lens Implantation for Unilateral Traumatic and Unilateral Congenital Cataract in Children

PURPOSE

To retrospectively estimate the long-term corneal endothelial cell loss in children after perforating corneal trauma and implantation of an iris-fixated anterior-chamber intraocular lens (IOL), either the Artisan aphakia lens or the Artificial Iris Implant, and to compare this corneal endothelial cell loss to that in children who received an Artisan aphakia lens to correct aphakia after cataract extraction for unilateral congenital cataract.

METHODS

A retrospective study was performed, evaluating the charts and endothelial photographs of 6 patients with unilateral traumatic cataract, with a mean age at IOL implantation of 9.5 years (range: 5.8-12.8 years) and a mean follow-up after IOL implantation of 10.5 years (range: 8.0-14.7 years), and of 3 children who were operated on for unilateral congenital cataract at a mean age of 2.7 years and who received an Artisan aphakia IOL, with a mean follow-up after IOL implantation of 9.5 years (range: 4.7-14.5 years). Parameters that were studied were central endothelial cell density (CECD) in both the operated and the normal eye at the last follow-up visit, percentage of cell loss in the operated eye compared with the normal eye, and length and location of the corneal scar in the injured eye.

RESULTS

: In the traumatic cataract group, CECD was, on average, 41% (range: 22%-58%) lower in the operated eye (1.647 +/- 322 [SD] cells/mm) than the normal eye (2.799 +/- 133 cells/mm). A significant negative linear correlation was found between the length of the corneal perforation scar and CECD. In the congenital cataract group, no statistical difference in CECD was found between the operated (3.323 +/- 410 cells/mm) and the unoperated (3.165 +/- 205 cells/mm) eye.

CONCLUSION

Endothelial cell loss 10.5 years after iris-fixated IOL implantation for traumatic cataract was substantial and related to the length of the corneal scar of the original trauma. In children operated on for congenital cataract, no difference was found in CECD in the operated and unoperated eyes 9.5 years after Artisan aphakia IOL implantation.

Clinical Results With the Medennium Phakic Refractive Lens for the Correction of High Myopia

PURPOSE

To evaluate the predictability, safety, stability, complications, and biocompatibility of the phakic refractive lens (PRL) as a posterior chamber intraocular lens to correct high myopia.

METHODS

Fifty eyes of 31 patients who underwent posterior chamber PRL implantation were evaluated prospectively. Mean preoperative myopia was -12.54 +/- 4.22 diopters (D) (range: -4.50 to -23.50 D) and mean astigmatic refractive power was -1.38 +/- 1.24 D (range: -1.00 to -4.50 D). Surgical implantation was performed through a 3.0- to 4.0-mm clear cornea sutureless incision using parabulbar (sub-Tenon's) anesthesia. Intra- and postoperative complications were recorded.

RESULTS

Three months after surgery, the mean spherical equivalent refraction was -0.21 +/- 0.42 D (range: +1.00 to -1.75 D). At 6 and 12 months, mean spherical equivalent refraction was -0.23 +/- 0.38 D (range: 0 to -1.25 D). At the last examination, uncorrected visual acuity was > or = 20/40 in 41 (82%) eyes and > or = 20/20 in 22 (44%) eyes. Best spectacle-corrected visual acuity (BSCVA) was > or = 20/40 in 42 (84%) eyes and > or = 20/20 in 27 (54%) eyes. Comparison of pre- and postoperative BSCVA at 12 months showed that 12 (36.4%) of 33 eyes gained > or =1 lines of BSCVA and 7 (21.2%) of 33 eyes gained > or =2 lines. One (2%) eye developed anterior subcapsular cataract requiring lens exchange, and 1 (2%) eye developed acute angle closure glaucoma requiring YAG-iridotomy. One (2%) eye developed macular hemorrhage.

CONCLUSIONS

At 6 months and 1 and 2 years, PRL implantation yielded encouraging visual and refractive results with excellent biocompatibility. The efficacy, stability, and short-term safety of this lens was established. Serious complications, such as cataract and acute angle closure glaucoma, may occur, and long-term safety needs to be evaluated.

Artisan Phakic Intraocular Lens Implantation After Retinal Detachment Surgery

PURPOSE

To report three cases of Artisan phakic intraocular lens (PIOL) implantation to correct myopic refractive error after previous retinal detachment surgery treated with scleral encircling.

METHODS

Artisan PIOLs were implanted in a 29-year-old man with -21.0 -2.0 x 180 manifest refraction and best spectacle-corrected visual acuity (BSCVA) of 20/40 (case 1), a 28-year-old woman with BSCVA of 20/20 and -8.5 -1.0 x 180 manifest refraction (case 2), and a 44-year-old man with BSCVA of 20/32 and -11.75 -1.75 x 10 manifest refraction (case 3).

RESULTS

In case 1, 24 months after implantation of the Artisan PIOL, uncorrected visual acuity (UCVA) was 20/40. In case 2, 24 months after surgery, UCVA was 20/32. In case 3, 3 months after surgery, UCVA was 20/32. There was no formation of new breaks, progressive vitreoretinal traction, or complications.

CONCLUSIONS

The Artisan PIOL may provide an alternative method to correct high myopia after retinal detachment surgery.

Iris-fixated toric phakic intraocular lens: Three-year follow-up

PURPOSE

To evaluate the 3-year safety, efficacy, predictability, and stability of iris-fixated toric phakic intraocular lens (pIOL) implantation for the correction of myopia or hyperopia with astigmatism.

SETTING

Department of Ophthalmology, Johannes Gutenberg University, Mainz, and Department of Ophthalmology, University Clinic, Bochum, Germany.

METHODS

A prospective clinical trial of 40 eyes of 23 patients with high ametropia and astigmatism was conducted. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity, refraction, astigmatism, intraocular pressure, slitlamp biomicroscopy, and indirect ophthalmoscopy were measured preoperatively and postoperatively.

RESULTS

Of the 40 eyes, 28 were myopic and 12 were hyperopic. Three years postoperatively, 70% of eyes were within +/-1.00 diopter (D) of the targeted refraction. In the myopic group, mean preoperative BSCVA was 20/40 and improved postoperatively to 20/25. Sixty-six percent of eyes gained 1 or more lines from the preoperative BSCVA. The mean cylinder decreased from -3.58 D +/- 1.26 (SD) preoperatively to -1.15 +/- 1.01 D postoperatively. In the hyperopic group, preoperative BSCVA was 20/25 and improved to 20/20 postoperatively. Thirty-six percent of eyes gained 1 or more lines from the preoperative BSCVA. The mean cylinder decreased from -3.37 +/- 0.88 D to -1.53 +/- 0.69 D postoperatively. The correction was stable in all eyes 3 years after surgery. No potentially sight-threatening complications occurred.

CONCLUSION

The 3-year follow-up showed the iris-fixated toric pIOL was effective in correcting high ametropia and astigmatism.

Recurrent iritis after implantation of an iris-fixated phakic intraocular lens for the correction of myopia

The iris-claw intraocular lens (IOL) was recently approved by the U.S. Food and Drug Administration for the correction of refractive disorders. Previous reports are not uniform regarding its potential to induce inflammatory reaction. We report the case of a young healthy patient who experienced persistent and intolerable iritis after implantation of an iris-claw IOL. The iritis was resolved only after explantation of the IOL.

Correction of high myopia with different phakic anterior chamber intraocular lenses: ICARE angle-supported lens and Verisyse iris-claw lens

PURPOSE

To evaluate the efficacy, predictability and safety of implanting two models of anterior chamber IOLs for high myopia. Comparison of the refractive results between two groups of patients implanted with different IOLs.

MATERIALS AND METHODS

Forty eyes were implanted with phakic IOLs. The ICARE myopia lens was implanted in 20 eyes of 12 patients with preoperative myopia that ranged from -21.875 to -10.0. The mean patients' age was 30 years. The Verisyse IOL was implanted in 20 eyes of 12 patients with spherical equivalent of the refractive error from -21.625 to -10.375D, and the mean patients' age was 32.25 years. The dioptric power of the intraocular lens was calculated by considering refraction, keratometry, and anterior chamber depth. The follow-up period was 12 months.

RESULTS

Twelve months after surgery, the mean refractive error (SE) was -0.19D (100% of eyes were within +/-1.0D of the target refraction) in the ICARE group, and -0.86D (95% of eyes were within +/-1.0D of the target refraction) in the Verisyse group. The postoperative refraction remained stable during the entire follow-up period. The mean uncorrected visual acuity was 0.7 in the ICARE group, and 0.69 in the Verisyse group 1 year postoperatively. There was no loss in visual acuity 1 year after surgery in the ICARE implanted eyes, one patient in the Verisyse group lost 1 line of BCVA as compared to the preoperative state. Mean endothelial cell density loss was 6.12% and 6.79% in the ICARE and Verisyse groups, respectively. There were no statistically significant differences regarding the analyzed outcome parameters between the two study groups.

CONCLUSION

The implantation of both anterior chamber phakic intraocular lenses to correct high myopia resulted in a stable and predictable refractive outcome. Efficacy and safety of surgery for both implanted lens models are very high.

Three-Year Follow-up Analysis of Artisan Toric Lens Implantation for Correction of Postkeratoplasty Ametropia in Phakic and Pseudophakic Eyes

PURPOSE

To determine the 3-year follow-up of efficacy and safety of Artisan toric iris-fixated lens implantation after penetrating keratoplasty (PK) to correct high ametropia and astigmatism.

DESIGN

Prospective noncomparative case series with a minimum follow-up of 1 year.

PARTICIPANTS

Artisan toric lens implantation was performed in 36 eyes of 35 patients who were contact lens intolerant or unable to wear glasses due to anisometropia and/or high astigmatism.

INTERVENTION

Thirty-six eyes of 35 consecutive patients received Artisan toric lens implantation for postkeratoplasty astigmatism and/or anisometropia.

MAIN OUTCOME MEASURES

Manifest refraction, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and corneal topography were determined or performed before surgery and at 3, 6, and 12 months and yearly intervals up to 4 years after surgery. Efficacy, safety, percent reduction of refractive astigmatism, anisometropia of defocus, and the astigmatism correction index were determined. A patient satisfaction questionnaire and specular microscopy were assessed.

RESULTS

The mean +/- standard deviation of preoperative refractive cylinder was -7.06+/-2.01 diopters (D) (range, -3.0 to -11.0), which was reduced to -1.73+/-1.25 D, -1.69+/-1.15 D, -1.94+/-1.68 D, -2.02+/-1.93 D, and -2.00+/-1.53 D at 6 months (n = 36), 1 year (n = 36), 2 years (n = 29), 3 years (n = 15), and the last follow-up examination (28.5+/-12.5 months, n = 36), respectively (P<0.001 for all time points, paired t test). The spherical equivalent was reduced from -3.19+/-4.31 D (range, +5.5 to -14.25 D) preoperatively to -1.03+/-1.20 D (range, +1.0 to -5.25 D) at the last follow-up. The UCVA and BSCVA were > or =20/40 in 31.6% and 80.6%, respectively. There was a loss of BSCVA of >2 lines in 8.3% of eyes and a gain of at least 2 lines in 8.3% of eyes. Percent reductions in refractive astigmatism and anisometropia of defocus were 88.8%+/-29.5% and 77.8%+/-19.3%, respectively. The astigmatism correction index was 96.0%+/-24.2%. Satisfaction increased from 3.6 to 8.0 (scale, 0-10) after implantation. The endothelial cell loss as compared with preoperatively was 13.8%+/-18.7% (n = 34), 21.2%+/-21.8% (n = 33), 29.6%+/-27.3% (n = 26), 30.4%+/-32.0% (n = 18), and 34.8%+/-26.3% (n = 6) at 6 months (P = 0.001), 1 year (P<0.001), 2 years (P<0.001), 3 years (P = 0.001), and 4 years postoperatively (P = 0.1), respectively. In 2 patients, irreversible graft rejections occurred, and in 1 patient, gradual endothelial decompensation occurred.

CONCLUSION

Artisan toric lens implantation after PK was effective for reduction of refractive astigmatism and ametropia. All patients were suitable for spectacle correction after implantation. There was continuing endothelial cell loss from 6 months to 3 years postoperatively. In 3 cases, corneal graft failure developed.

Long-Term Complications of Iris-Claw Phakic Intraocular Lens Implantation in Weill-Marchesani Syndrome

PURPOSE

This study was designed to report the long-term complications of iris-claw phakic intraocular lens implantation in a patient with Weill-Marchesani syndrome.

METHODS

Case report and literature review.

RESULTS

A 26-year-old man with a history of glaucoma had bilateral phakic lens implantation for high myopia 10 years previously. Two years later, the left implant dislocated and was repositioned. Slit-lamp examination of both eyes revealed phakic implants of the iris-claw variety. There were moderate iridocorneal adhesions in the areas in which the lens haptics pinched the iris in both eyes and moderate epithelial and stromal edema over the temporal one-third of the left cornea. The crystalline lenses were clear with 3+phacodonesis OU. Dilated fundus examinations revealed bilateral severe optic nerve cupping. Crystalline lens diameters were measured at 7.5mm in the right eye and 8 mm in the left. Anterior chamber depths were 2.63 mm OD and 2.40 mm OS. Specular microscopy revealed central endothelial cell counts of 1133 and 587 cells/mm OD and OS, respectively. Axial lengths were 23.3 mm OD and 25 mm OS. Gonioscopic examination revealed bilateral angle closure with marked peripheral anterior synechiae. Based on our findings of short stature, shortened and thickened fingers, relatively normal axial length, microspherophakia, high myopia, and glaucoma, we diagnosed the patient with Weill-Marchesani syndrome.

CONCLUSION

Iris claw-lens phakic lenses may be an effective surgical alternative to correct high myopia in select patients; however, it may produce long-term complications in eyes with specific features.

Implantation of Verisyse Phakic Intraocular Lens to Correct Myopic Refractive Error After Penetrating Keratoplasty in Pseudophakic Eyes

PURPOSE

We report 2 cases in which a Verisyse phakic intraocular lens (PIOL) was used to successfully treat high myopia after penetrating keratoplasty (PK) in pseudophakic patients.

METHODS

Case 1 involved a 69-year-old pseudophakic man with a manifest refraction (MR) of -6.50 + 1.75 x 048 and a best spectacle corrected visual acuity (BSCVA) of 20/40 approximately 16 months after PK in the right eye. Case 2 was a 78-year-old pseudophakic man who had an MR of -9.00 + 5.75 x 132 with a BSCVA of 20/100 approximately 24 months after PK in the left eye.

RESULTS

In case 1, 10 months after Verisyse PIOL implantation, the MR was pl +2.00 x 135 with a BSCVA of 20/30. Endothelial cell density (ECD) in this patient decreased from 1926.1 to 815.3 cells/mm over 17 months. In case 2, 24 months after Verisyse PIOL implantation, the MR was -3.25 + 3.50 x 105 with a BSCVA of 20/60. ECD in this patient decreased from 2108.4 to 753.8 cells/mm in 30 months.

CONCLUSION

The Verisyse PIOL may provide an alternative method to correct high myopia for anisometropia in pseudophakic patients after PK. In this report, PIOL implantation was associated with a decrease in ECD. Further studies are required to determine the long-term effects and ultimate safety of PIOL placement on the integrity of the cornea endothelium after corneal transplant in pseudophakic patients.

Short-term Follow-up after Implantation of a Foldable Iris-Fixated Intraocular Lens in Phakic Eyes

OBJECTIVE

To evaluate efficiency, predictability, stability, complications, and patient satisfaction after implantation of a foldable iris-fixated phakic intraocular lens (PIOL) for the correction of myopia.

DESIGN

Prospective, nonrandomized, comparative (self-controlled) trial.

PARTICIPANTS

Forty-one eyes of 22 myopic patients aged 18 to 56 years (mean, 36 years) with average sphere of -8.2+/-2.01 diopters (D; range, -12.25 to -3.75 D) and average preoperative cylinder of -0.90+/-0.62 D (range, -2.50 to 0.00 D) were enrolled in this prospective study.

METHODS

All eyes underwent implantation of a foldable iris-fixated PIOL with an optical zone of 6.0 mm. The follow-up was 6 months in all cases. Phakic intraocular lenses were available in powers ranging from -2.0 D to -12.0 D.

MAIN OUTCOME MEASURES

The main parameters assessed were best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity, refraction, endothelial cell count, intraocular pressure, slit-lamp biomicroscopy, and indirect ophthalmoscopy.

RESULTS

At 6 months' follow-up, no eyes experienced a loss in BSCVA and 78% gained 1 or more lines of their preoperative BSCVA. Uncorrected visual acuity was significantly improved, with 82% of eyes reaching 20/25 or better. There was a significant reduction in spherical errors in all patients after surgery. Ninety-one percent of eyes were within +/-0.50 D of target refraction. A slight loss of endothelial cells (2.3 %) was observed 6 months after surgery. There were no intraoperative complications. In the postoperative follow-up, however, pigment precipitates were noted in 5 eyes of 4 patients.

CONCLUSIONS

At short-term follow-up, the implantation of the foldable iris-fixated PIOL proved to be effective and predictable for the correction of myopia in phakic eyes. However, longer follow-up with larger numbers of patients is necessary to evaluate long-term complications.

Phakic Intraocular Lenses

An analytical review of the data available in the field of phakic intraocular lens implantation was conducted. Particular attention was paid to the more critical issues of intraocular lens sizing and safety guidelines. A comprehensive, competitive analysis of different implantation sites, intraocular lens model designs, and safety guidelines has been included. Specialized biometry techniques, such as very high frequency ultrasound and Scheimpflug imaging, have been reviewed, and a critical review of commercial claims regarding intraocular lens technologies has been included. Clinical studies of phakic intraocular lenses demonstrate increasing promise for the correction of refractive errors not amenable to mainstream excimer laser refractive surgery. The main issues currently revolve around adequate lens design (VHF ultrasound study suggests that custom-design and sizing may be the most effective and safest approach for every phakic IOL model), because these devices will be required to remain physiologically inert and anatomically compatible with internal ocular structures and relations for several decades. The possibility of safe removing or exchanging the IOL should remain a feasible option over time. It is of utmost importance that we continue to critically evaluate current encouraging short-term outcomes, which are being extrapolated to the longer term by ongoing high resolution imaging and monitoring of the anatomical and functional relations of implanted phakic IOLs.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses which are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for posterior chamber lenses these are mainly cataract formation and pigment dispersion. RLE is preferable in cases of high ametropia in which the natural lens has lost its accommodative effect. The main complications for myopic RLA include retinal detachment, while hyperopic refractive lens exchange may be associated with surgical problems in the narrower anterior eye segment.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

Artisan Phakic Intraocular Lens for Correcting High Myopia

OBJECTIVES

To evaluate the safety indexes and efficacy of Artisan phakic intraocular lens (IOL) for the correction of high myopia.

METHODS

Retrospective interventional case series reports. Thirty-one eyes (22 patients) with myopia from -5.25 to -19.00 diopters underwent implantation of an Artisan phakic IOL. Follow-up examinations were performed at 1 day, 1 week, 1 month, and 3 months. The following parameters were recorded: manifest refraction, slit-lamp examination, applanation tonometry, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), complications or adverse reactions. The primary variable was the refractive outcome at 3 months. Secondary variables were change in BSCVA, and efficacy and safety indexes.

RESULTS

At 3 months, mean spherical equivalent was -0.50 +/- 0.36 diopters (range, -1.25 - plano). In 29 eyes (93.5%) UCVA was 6/12 or better; the other three eyes had UCVA of 6/15. The difference between preoperative and 1 week postoperative BSCVA was not statistically significant (p = 0.25). Comparison of BSCVA at 1 week and at 1 month was statistically significant (p = 0.05); this difference was even more significant at 3 months (p = 0.01). The BSCVA remained the same or improved for all the eyes. BSCVA for 20 eyes (64.5%) had improved one or more lines in visual acuity. Mean endothelial cell loss at 3 months was 3.96%.

CONCLUSION

The Artisan lens is a safe, predictable, and efficacious method to correct high myopia. Postoperative gain in BSCVA was achieved for the majority of eyes. Future study to assess safety indexes and risk of complications is required with long-term follow-up.

Experience with the Artisan phakic intraocular lens in Asian eyes

PURPOSE

To investigate the efficacy and safety of implantation of an iris-claw phakic intraocular lens (PIOL), Artisan Myopia, in Asian eyes.

SETTING

Minamiaoyama Eye Clinic, Tokyo, Japan.

METHODS

Forty-four eyes of 32 Japanese patients and 1 Korean patient with high myopia had Artisan Myopia lens implantation to correct their refractive errors. Lens models, 5/8.5 or 6/8.5 (optic diameter/overall diameter), were chosen as standard lens model. A smaller lens model (5/7.5-Artisan Myopia Small) was implanted in eyes with corneal diameter less than 11.0 mm. Postoperative examinations were performed on 1 day, 1 week, 1 month, 3 months, 6 months, 1 year, and 2 years after surgery. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest refraction, corneal endothelial cell counts, intraocular pressure, and complications were evaluated.

RESULTS

Artisan Myopia Small lenses were implanted in 4 eyes (9.1%) and 8.5 mm diameter lenses were implanted in 40 eyes. Preoperative UCVA (logMAR) improved from 1.57 to 0.09 at 1 month after surgery and no regression was observed thereafter. Postoperative manifest refraction was -1.02 +/- 0.87 D (-3.25 to -0.00 D), and within 1.0 D in 20 eyes (55.6%), within 2.0 D in 32 eyes (88.9%) at 1 month after surgery, and stable during the follow-up period. The final BCVA decreased 2 lines in 2 eyes (4.5%) due to progression of age-related cataract. No serious complications such as angle closure or progressive endothelial cell loss were observed.

CONCLUSION

Implantation of an Artisan iris-claw PIOL implantation may be a safe and effective procedure for Asian eyes.

Contact entre le cristallin naturel et différents modèles d’implants réfractifs phakes. Étude avec l’OCT de chambre antérieure

Three patients received three different models of phakic implants. With the usual slit-lamp examination method, we were not able to establish whether there was contact between the implants and the natural crystalline lens. Using the anterior chamber optical coherence tomography scanner (AC-OCT), we were able to demonstrate that there was direct contact between the natural crystalline lens and the three different phakic implants. A dynamic study of these contacts was carried out during accommodation. These observations show that examination of the anterior segment with the optical coherence tomography scanner is essential in refractive surgery.