Posterior Chamber Phakic Intraocular Lens for Myopia of -8 to -19 Diopters

Monte-Carlo simulation for calculating phakic supplementary lenses based on a thick and thin lens model using anterior segment OCT data

BACKGROUND

Phakic lenses (PIOLs, the most common and only disclosed type being the implantable collamer lens, ICL) are used in patients with large or excessive ametropia in cases where laser refractive surgery is contraindicated. The purpose of this study was to present a strategy based on anterior segment OCT data for calculating the refraction correction (REF) and the change in lateral magnification (ΔM) with ICL implantation.

METHODS

Based on a dataset (N = 3659) containing Casia 2 measurements, we developed a vergence-based calculation scheme to derive the REF and gain or loss in ΔM on implantation of a PIOL having power PIOLP. The calculation concept is based on either a thick or thin lens model for the cornea and the PIOL. In a Monte-Carlo simulation considering, all PIOL steps listed in the US patent 5,913,898, nonlinear regression models for REF and ΔM were defined for each PIOL datapoint.

RESULTS

The calculation shows that simplifying the PIOL to a thin lens could cause some inaccuracies in REF (up to ½ dpt) and ΔM for PIOLs with high positive power. The full range of listed ICL powers (- 17 to 17 dpt) could correct REF in a range from - 17 to 12 dpt with a change in ΔM from 17 to - 25%. The linear regression considering anterior segment biometric data and the PIOLP was not capable of properly characterizing REF and ΔM, whereas the nonlinear model with a quadratic term for the PIOLP showed a good performance for both REF and ΔM prediction.

CONCLUSION

Where PIOL design data are available, the calculation concept should consider the PIOL as thick lens model. For daily use, a nonlinear regression model can properly predict REF and ΔM for the entire range of PIOL steps if a vergence calculation is unavailable.

Retinal complications post posterior chamber phakic intraocular lens implantation at a tertiary eye hospital in the Eastern Province of Saudi Arabia

PURPOSE

Phakic intraocular lenses treat higher degrees of myopia not possible previously with conventional refractive surgery. The aim of this study is to report the incidence and risk factors of retinal complications after posterior chamber PIOL implantation and assess the differences in biometric parameters between patients who developed such complications versus those who did not.

METHODS

This retrospective study recruited 514 patients who underwent ICL implantation to correct myopia at a tertiary eye hospital center in the Eastern province of Saudi Arabia. Follow up period was at least one year. Medical records of the patients were reviewed to obtain the required data. Associations between respondents' characteristics and retinal complications were evaluated using the Chi-squared test.

RESULTS

The mean (SD) age was 27.7 (± 6.5) years ranging from 18 to 47. Laser treatment was performed in 14 cases (2.7%). Retinal complications occurred in six cases (1.2%). The risk of retinal complication was significantly higher among patients with high axial length (OR = 1.3, 95% CI 1.2, 1.4) and patients with high pre-spherical equivalent before ICL (OR = 1.09, 95% CI 1.03, 1.4).

CONCLUSION

Patients with higher axial length and higher pre-spherical equivalent before ICL implantation are at high risk of retinal complications.

Evaluation of phakic intraocular lens power calculation using the new Linz-Homburg-Castrop formula and comparison with four conventional methods

PURPOSE

To evaluate the accuracy of phakic intraocular lens (pIOL) power calculation in a middle European patient cohort.

SETTING

EyeLaser Clinic, Linz, Austria.

DESIGN

Single-center single-surgeon retrospective consecutive case series.

METHODS

Patients were included after uneventful pIOL surgery implanting 91 nontoric and toric Visian implantable collamer lens model V4c. Online Calculation and Ordering System (OCOS) software, JPhakic software, Olsen-Feingold formula, Holladay formula, and Linz-Homburg-Castrop (LHC) formula were compared. When possible, lens constants were optimized for the patient cohort. Data of single eye per patient were included. Outcome measures were mean absolute prediction error, median absolute prediction error, mean prediction error with SD, and median prediction error, as well as the percentage of eyes with an absolute prediction error within limits of 0.25 diopters (D), 0.5 D, 0.75 D, and 1.0 D.

RESULTS

91 eyes of 91 patients were assessed. After application of the Cochran Q test, the Olsen-Feingold formula achieved a significantly lower percentage of eyes within an absolute prediction error of 1.0 D than all other methods.

CONCLUSIONS

In the patient cohort, OCOS software, JPhakic software, and Holladay and LHC formulas showed equal results and can be cross-checked. The LHC formula was not published before. A ready-to-use Excel sheet is available as an addendum.

Corneal diameter measurements by 3 optical biometers and their effect on phakic intraocular lens sizing

PURPOSE

To compare phakic intraocular lens size calculations based on corneal diameter (CD) measurements by 3 instruments.

SETTING

G.B. Bietti Foundation I.R.C.C.S., Rome, Italy.

DESIGN

Retrospective interventional case series.

METHODS

Preoperatively, CD was measured with the Aladdin, IOLMaster 700, and Pentacam AXL Wave. The simulated ICL size was computed by entering CD measurements into the manufacturer's calculator. Postoperatively, vaulting was measured by anterior segment optical coherence tomography. The optimal ICL size (OIS) was calculated and compared with the commercially available OIS (CAOIS).

RESULTS

54 eyes (29 patients) with the implantable collamer lens (ICL) were enrolled. The mean CD was 12.02 ± 0.36 mm with the Aladdin, 12.35 ± 0.39 mm with the IOLMaster 700, and 12.22 ± 0.41 mm with the Pentacam AXL Wave ( P < .0001), with the closest agreement between the Pentacam AXL Wave and IOLMaster 700 (95% limits of agreement: -0.43 to +0.17 mm). Vaulting (mean: 558 ± 261 μm) was within 251 and 1000 μm in 49 eyes (83.3%). The mean difference between the simulated ICL size and OIS ranged between -0.11 ± 0.35 mm and 0.10 ± 0.30 mm ( P < .0001), with no statistically significant difference between the IOLMaster 700 and Pentacam AXL Wave. The simulated ICL size was equal to CAOIS in 38 eyes (70.37%) with the Aladdin, 37 eyes (68.52%) with the IOLMaster 700, and 39 eyes (72.22%) with the Pentacam AXL Wave, without any statistically significant difference.

CONCLUSIONS

CD measurements by the 3 devices lead to similar percentages of eyes with an ICL size equal to the OIS. Agreement is closer between the IOLMaster 700 and Pentacam AXL Wave.

Long-term Comparison of Vault and Complications of Implantable Collamer Lens with and without a Central Hole for High Myopia Correction: 5 Years

PURPOSE

To investigate the long-term safety, efficacy, stability, vault, and complications of implantable collamer lens with (ICL V4c) and without (ICL V4) a central hole for correcting high myopia.

METHODS

78 eyes (40 patients) underwent ICL V4c implantation and 78 eyes (48 patients) underwent ICL V4 implantation were enrolled. They were followed up for 5 years of the uncorrected and corrected distance visual acuity, spherical equivalent (SE), axial length, intraocular pressure, endothelial cell density and vault.

RESUITS

The safety indices of the ICL V4c and V4 groups at 5 years were 1.25 ± 0.40 and 1.31 ± 0.40, respectively (P = .353). The efficacy indices were 0.90 ± 0.29 and 1.00 ± 0.44, respectively (P = .098). The preoperative, 1 month and 5 year postoperative logMAR UDVAs were respectively 1.54 ± 0.48, 0.11 ± 0.17, and 0.20 ± 0.26 in the V4c group and 1.56 ± 0.44, 0.14 ± 0.19, and 0.22 ± 0.26 in the V4 group (P = .703, 0.329, 0.585). The logMAR CDVAs were resepectively 0.13 ± 0.18, 0.02 ± 0.11, and 0.05 ± 0.16 in the V4c group and 0.18 ± 0.22, 0.05 ± 0.14, and 0.09 ± 0.21 in the V4 group (P = .128, 0.169, 0.229). The SE were resepectively -15.10 ± 4.32 D, -0.71 ± 1.31 D and -1.65 ± 1.30 D in the V4c group and -15.44 ± 3.51 D, -0.61 ± 1.12 D and -1.40 ± 1.30 D in the V4 group (P = .585, 0.637, 0.296). The mean vault reduced by 97.31 ± 136.61 μm in the V4c group and by 99.74 ± 245.83 μm in the V4 group. Three eyes (3.85%) with mid-periphery anterior subcapsular opacification in the V4c group and two (2.56%) with cataract, one (1.28%) with central anterior subcapsular opacification in the V4 group were observed. The CDVA of 20/40 was obtained in the two cataract eyes after phacoemulcification and intraocular lens implantation.

CONCLUSION

Long-term ICL V4c and ICL V4 implantations are safe, effective, and stable for high myopia correction. ICL V4c can potentially reduce the risk of lens opacification and may be more tolerant to low vault than ICL V4.

Comparison of clinical outcomes of implantable collamer lens implantation with and without use of an ophthalmic viscosurgical device

PURPOSE

To compare the clinical efficacy of posterior chamber phakic implantable collamer lens (ICL) implantation with and without the use of an ophthalmic viscosurgical device (OVD).

SETTING

Onnuri Eye Hospital, Jeonju, Jeollabuk-do, South Korea.

DESIGN

Retrospective case series.

METHODS

Included were patients who underwent ICL implantation with the use of an OVD (OVD group) and patients who underwent ICL implantation without the use of an OVD (hydro group). Refractive error, endothelial cell density (ECD), intraocular pressure (IOP), vault, and adverse events were evaluated at 1 day, 1 week, 1 month, and 3 months postoperatively. The IOP and vault were checked 1 hour postoperatively, and the surgical time was recorded.

RESULTS

The OVD group comprised 54 eyes of 27 patients and the hydro group 49 eyes of 25 patients. There were no significant preoperative differences between the 2 groups. At 1 hour postoperatively, the IOP was significantly higher in the OVD group (P < .001); however, there was no significant difference in IOP between the 2 groups at other follow-up timepoints. Surgical time was significantly shorter for the hydro group (P = .032). There was no statistically significant difference in vault, ECD, or refractive error between the 2 groups during the 3-month follow-up period. No adverse events were observed.

CONCLUSIONS

ICL implantation without the use of an OVD was safe and effective. The advantages of this technique included a short surgical time, prevention of early postoperative IOP spikes, and cost savings due to OVD elimination.

Intraoperative Versus Postoperative Vault Measurement After Implantable Collamer Lens Implantation in a Large Cohort of Patients

PURPOSE

To compare intraoperative and postoperative central vault measurement after implantable Collamer lens (ICL; STAAR Surgical) implantation using optical coherence tomography (OCT).

METHODS

A total of 574 eyes of 338 consecutive patients undergoing myopic ICL implantation were evaluated (mean age of 30.8 ± 5.7 years, 117 men and 221 women). Central ICL vault was measured both intraoperatively using the microscope-integrated iOCT (Optomedical Technologies GmbH) mounted on a standard surgical microscope (HS Hi-R NEO 900A; Haag-Streit Surgical GmbH), and postoperatively using the CASIA2 swept-source OCT (Tomey GmbH) at 4 and 24 hours.

RESULTS

Mean differences between intraoperative and postoperative vault values were 11.5 ± 29.0% of the mean value 4 hours postoperatively (P < .001) and 2.7 ± 33.5% of the mean value 24 hours postoperatively (P < .001). Correlation analysis shows significant agreement between vault values obtained intraoperatively and at the two postoperative times, 4 hours (Spearman Rho = 0.850, P < .001) and 24 hours (Spearman Rho = 0.745, P < .001). In 73% of cases, postoperative vault values 4 hours after the surgery could be predicted from intraoperative vault values, and so were 56% of vault values 1 day after surgery. Significant differences in vault were found at the different times, grouping cases by ICL size (Kruskal-Wallis, P = .028 for intraoperative vault, and P < .001 for both postoperative vault times), with smaller vault values for the smaller ICL size.

CONCLUSIONS

Intraoperative determination of ICL vault using iOCT is an effective method for predicting postoperative ICL vault and minimizing postoperative vault surprises that could require surgical retouching. [J Refract Surg. 2021;37(7):477-483.].

PRESBYOPIA MANAGEMENT WITH DIFFRACTIVE PHAKIC POSTERIOR CHAMBER IOL

OBJECTIVE

To evaluate safety and refractive efficiency after posterior chamber diffractive implantable phakic contact lens (IPCL) surgery.

MATERIAL AND METHODS

A prospective non-randomized case-series study was performed on 54 myopic eyes of 27 patients who had undergone diffractive IPCL surgery. Corneal endothelial cell density (ECD), central corneal thickness (CCT), intra-ocular pressure (IOP), vault, uncorrected distance (UDVA), spherical equivalent (SE) and defocus curve, were all evaluated twelve months after surgery. The presence of cataracts was evaluated by slit-lamp during a postoperative follow-up.

RESULTS

Mean age was 47 ± 2.62 years-old. Mean SE decreased, from -5.95 ± 2.56 D in a pre-operative stage, to -0.25 ± 0.25 D twelve months after surgery. Achieved UDVA was 20/20 in 24.1% of all cases, 20/25 in 74.1% of them, and 20/32 in all remaining cases. No eyes suffered lost lines of vision. The binocular defocus curve was 0.06 ± 0.05 logMAR for a -3.0 D of defocus; 0.11 ± 0.04 logMAR for a -1.5 D of defocus, and 0.08 ± 0.03 logMAR for a 0 D of defocus. Twelve months after surgery, mean ECD had decreased by 1.43 %, whereas mean CCT had increased by 0.06 %, without any significant statistical difference (p = 0.28 and p = 0.93 respectively). No difference (p: 0.86) in the vault was observed at 6 months vs.12 months, as well as between IOP measurements (p = 0.22). There were no non-intra or postoperative complications, and, specifically, no cataracts developed either.

CONCLUSIONS

Diffractive IPCL was implanted safely. Corneal endothelial CD, CCT, vault, and IOP remained stable twelve months after surgery. Visual acuity for distance, intermediate and near sight were achieved without spectacles.

Posterior Chamber Phakic Intraocular Lens Implantation for the Correction of Myopia and Myopic Astigmatism: A Retrospective 10-Year Follow-up Study

PURPOSE

To assess the 10-year clinical outcomes of implantable collamer lens (ICL) implantation for myopia and astigmatism.

DESIGN

Retrospective observational case series.

METHODS

This study included 114 eyes of 61 patients who underwent ICL implantation for correction of myopia and myopic astigmatism. We assessed the safety, efficacy, predictability, stability, and adverse events preoperatively, at 6 months (106 eyes) and 1 (94 eyes), 3 (58 eyes), 5 (65 eyes), 8 (89 eyes), and 10 (70 eyes) years postoperatively. Only the eyes with clinical data available at each follow-up time were analyzed.

RESULTS

The mean logMAR uncorrected and corrected distance visual acuities were -0.01 ± 0.24 and -0.18 ± 0.07 at 10 years postsurgery. The mean indices for safety and efficacy were 0.88 ± 0.15 and 0.66 ± 0.26, respectively. At 10 years postsurgery, 71.4% and 87.1% of the eyes were within 0.5 and 1.0 diopters (D), respectively, of the attempted spherical equivalent correction. The mean intraocular pressure was 13.1 ± 2.4 mmHg preoperatively and 13.1 ± 2.9 mmHg at 10 years postoperatively. The mean endothelial cell loss was 5.3% at 10 years postsurgery. Twelve of 114 eyes (10.5%) developed anterior subcapsular cataract during 5-10 years' follow-up; among these, 4 eyes (3.5%) were symptomatic and ICL explantation and phacoemulsification surgery were performed. No vision-threatening complications occurred during the observation period.

CONCLUSION

ICL implantation offered good overall outcomes in all measures of safety, efficacy, predictability, and stability for the correction of myopia and myopic astigmatism throughout a long-term follow-up period of 10 years.

[Intraocular pressure after implantation of an ICL with aquaport : Development of intraocular pressure after implantation of an ICL (model V4c) with aquaport without iridotomy]

BACKGROUND AND OBJECTIVE

The latest version of the intraocular lens (ICL V4c) has a central hole (aquaport) that avoids a pupillary block. Due to this laser iridotomy or intraoperative surgical peripheral iridectomy are no longer required. In this study, we examined the intraocular pressure (IOP) after implantation of the ICL with aquaport, with special reference to the development of a possible pupillary block glaucoma.

MATERIAL AND METHODS

This retrospective non-randomized study included 87 eyes from 46 patients (consecutive case series). These patients had the ICL model V4c (without a laser iridotomy or peripheral iridectomy) implanted between January 2013 and October 2014. The preoperative IOP values were compared with the postoperative values 1-2 h, 1 day, 1 week and 1 month after implantation.

RESULTS

The median intraocular pressure was 14 ± 2 mm Hg before implantation of the ICL, palpatory normotensive 1-2 h after implantation, 13 ± 3 mm Hg 1 day after implantation, 15 ± 3 mm Hg 1 week after implantation and 16 ± 4 mm Hg 1 month after implantation (a slight statistically significant increase of the intraocular pressure, p < 0.05). In 2 patients there was a steroid response in both eyes with IOP reaching up to a maximum of 28 mm Hg. There were no peaks of intraocular pressure due to a pupillary block.

CONCLUSION

It is possible to implant the latest ICL V4c with a central hole (Aquaport) without a laser iridotomy or peripheral iridectomy or development of a pupillary block.

Pars plana vitrectomy in management of giant retinal tear and retinal detachment following iris-fixated anterior chamber phakic intraocular lens implantation

This case report describes a 26-year-old man presenting with a giant retinal tear (GRT) with retinal detachment (RD) following implantation of iris-fixated anterior chamber phakic intraocular lens (AC-PIOL) for high myopia and occurrence of intraoperative aberrations during vitrectomy due to the presence of AC-PIOL in situ. Posterior chamber PIOL have been well reported to be associated with GRT with RD. Very few reports exist of GRT with RD following AC-PIOL. Moreover, the presence of iris-fixated AC-PIOL, in this case, led to the formation of ghost images intraoperatively especially during crucial steps like induction of posterior vitreous detachment which has never been reported.

Reverse Pupillary Block After Retinal Detachment Surgery in an Eye with Toric Implantable Collamer Lens

PURPOSE

To report an interesting phenomenon, after vitreoretinal surgery, in an eye with toric implantable collamer lens (ICL).

METHODS

A 20-year-old male presented with raised intraocular pressure (IOP) after the retinal detachment surgery in the left eye. He had toric ICL in both the eyes, and left eye showed shallow peripheral anterior chamber depth (ACD), narrow iridocorneal angle (ICA), increased ICL vault and pigments debris blocking central hole. After dilation, peripheral ACD deepened, ICL vault decreased and ICA increased, with posterior bowing of iris.

RESULTS

Patient was managed with topical steroids and antiglaucoma medications. A month later, after inflammation subsided, central hole of ICL became patent, peripheral ACD deepened, ICA increased and IOP was normal without medications, however, after dilation, posterior bowing of iris persisted. He was speculated to have unusual presentation of reverse pupillary block in the left eye after mydriasis. This phenomenon was not observed in the right eye.

CONCLUSION

Reverse pupillary block, after dilation is an unusual phenomenon, which was seen in a silicone-filled eye with toric ICL implant. In cases of inflammatory debris blocking Aquaport opening of ICL, conservative management with topical steroids and antiglaucoma medications can help reduce inflammation and IOP, alleviating need for any intervention, such as laser iridotomy.

Phake Intraokularlinsen

Die Implantation von phaken Intraokularlinsen stellt eine etablierte Therapieform zur Korrektur von höhergradigen Ametropien bei Myopie und Hyperopie sowie kombinierten Refraktionszuständen mit Astigmatismen dar. Bei der Anwendung sind gewisse anatomische und refraktive Voraussetzungen zu beachten. Der Artikel beschreibt die aktuell gängigen Verfahren und Intraokularlinsensysteme unter besonderer Berücksichtigung der Möglichkeiten und Grenzen.

Comparison of peripheral iridectomy methods for posterior chamber phakic intraocular lens implantation in patients with brown irides

Background

We explore and compare the advantages and disadvantages of different operating methods for a peripheral iridectomy (PI) for phakic posterior chamber implantable contact lens (ICL) implantation in patients with dark-brown irides.

Methods

Forty-six patients completed this prospective comparative study. Neodymium: yttrium-aluminum-garnet (Nd:YAG) PI was performed in 15 patients (30 eyes) 2 weeks prior to surgery (YAG PI group). Surgical PI was performed in 17 patients (34 eyes) 2 weeks prior to the ICL implantation (preoperative PI group), and intraoperative PI was performed during ICL implantation in 14 patients (28 eyes) (intraoperative PI group). The postoperative recovery of visual acuity, intraoperative complications, operation duration, and patients’ visual disturbances were compared.

Results

Compared with the preoperative BCVA, the uncorrected visual acuity (UCVA) at 1 week was markedly restored in the preoperative PI group (P = 0.004). UCVA in the three groups of patients had all recovered well at 1 and 3 months after ICL implantation and were significantly better than the preoperative BCVA (all P < 0.01). In the YAG PI group, iris bleeding occurred in nine eyes (30.0 %) and 14 eyes (46.7 %) had pigment dispersion; these values were significantly higher than those in the preoperative PI group (5.9 and 14.7 %, respectively, both P = 0.01). In the intraoperative PI group, elevated high intraocular pressure occurred in four eyes (14.3 %), and eight eyes (28.6 %) had varying degrees of pigment dispersion after ICL implantation.

Conclusions

For patients with dark-brown irides, surgical PI performed 2 weeks prior to the implantation facilitated better postoperative recovery of visual acuity.

Trial registration

Current Controlled Trials ISRCTN35178162. Retrospectively registered March 4th, 2013.

Long-term clinical results of posterior chamber phakic intraocular lens implantation to correct myopia

BACKGROUND

The aim of this study was to determine whether implantable collamer lens (ICL) implantation to correct myopia is an effective and safe surgical option even after long-term follow up.

DESIGN

A retrospective observational study was carried out.

PARTICIPANTS

A total of 281 eyes of 145 myopic patients were included in the study.

METHODS

Patients underwent ICL implantation and had the follow-up period of at least 5 years (87 ± 18.9 months).

MAIN OUTCOME MEASURES

Outcome measures included uncorrected and corrected distance visual acuities, refraction for the evaluation of efficacy, safety, stability and predictability, ICL vault and adverse events.

RESULTS

The final mean logMAR uncorrected and corrected distance visual acuities were 0.02 ± 0.19 and -0.12 ± 0.13, respectively. The mean efficacy and safety indices were 1.04 ± 0.32 and 1.20 ± 0.26. The mean spherical equivalent decreased from -8.74 ± 2.27 diopter (D) to -0.58 ± 0.72 D, and there was high predictability with 69.8% and 87.2% having a postoperative refraction within 0.5 D and 1.0 D, respectively. The mean postoperative vault was changed from 2.53 ± 0.6 to 2.00 ± 0.7. Six (2.1%) eyes developed cataract, and the mean endothelial cell loss was 7.8 ± 8.3%. Increased intraocular pressure was found in two (0.7%) eyes that required the exchange of lenses with different sizes.

CONCLUSIONS

Implantable collamer lens implantation to correct myopia was an effective and safe surgery with high predictability and stability during long-term follow up. Slight myopic shift and cataract formation related with change in vault should be further evaluated.

Posterior chamber collagen copolymer phakic intraocular lens with a central hole to correct myopia: One-year follow-up

PURPOSE

To assess the predictability, stability, efficacy, and safety of a newly developed posterior chamber phakic intraocular lens (pIOL) (model V4c Visian Implantable Collamer Lens) to correct moderate to high myopia.

SETTING

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Prospective case series.

METHODS

This study evaluated eyes that had implantation of the new pIOL model with a central hole for myopia correction. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density, pIOL vault, and adverse events were evaluated over 12 months.

RESULTS

The study comprised 147 eyes of 80 patients. Preoperatively, the mean spherical equivalent (SE) was -8.80 diopters (D) ± 2.60 (SD). At 12 months, the mean SE was -0.14 ± 0.26 D, with 93.9% of eyes within ±0.50 D of the target and 100% of eyes within ±1.00 D. The mean UDVA and CDVA were 0.028 ± 0.055 logMAR and 0.003 ± 0.013 logMAR, respectively. The efficacy and safety indices were 1.00 and 1.04, respectively. All eyes had unchanged CDVA or gained 1 or more lines during the follow-up. The IOP remained stable over time; no eye developed anterior subcapsular cataract. Twelve months postoperatively, the mean vault was 405.5 ± 184.7 μm (range 100 to 980 μm), and the mean endothelial cell loss was 1.7%.

CONCLUSION

The good refractive and visual acuity outcomes and the highly stable IOP values obtained over 12 months support the use of the new pIOL model with a central hole for the correction of moderate to high myopia.

FINANCIAL DISCLOSURE

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

Implantable Collamer Lens for Myopia: Assessment 12 Years After Implantation

PURPOSE

To evaluate the long-term refractive and visual stability and the risks related to the implantation of Implantable Collamer Lens (ICL; STAAR Surgical, Monrovia, CA) phakic intraocular lens (PIOL) for myopia.

METHODS

This retrospective, consecutive, cumulative clinical study was performed in a group of 144 eyes implanted with ICL PIOL for myopia. Only the cases with clinical data available 12 years after the implantation were included in the series. Corrected distance visual acuity (CDVA), uncorrected distance visual acuity, spherical equivalent, refractive astigmatism, endothelial cell density, ICL vaulting, and postoperative complications were analyzed.

RESULTS

Mean spherical equivalent refraction was -16.90±4.26 diopters (D) preoperatively and -1.77±1.93 D 12 years postoperatively. Mean CDVA at the first and last visit were 0.31±0.19 logMAR and 0.22±0.22 logMAR, respectively (Mann-Whitney U test, P<.001). Twelve years postoperatively, 8.9% of eyes had lost more than two lines of CDVA. The incidence of clinically relevant cataracts (13.88%) was significantly linked to the use of the V3 model ICL (chi-square test, P=.007). During the follow-up period, a significant reduction in PIOL vaulting was observed (Kruskal-Wallis test, P<.05), and the mean endothelial cell density decreased by 19.75%.

CONCLUSIONS

The ICL PIOL provided good refractive outcomes and stability in the long term. The incidence of cataracts is low when the latest models of this PIOL are used.

Effect of Myopic Defocus on Visual Acuity after Phakic Intraocular Lens Implantation and Wavefront-guided Laser in Situ Keratomileusis

This study aimed to investigate the effect of myopic defocus on visual acuity after phakic intraocular lens (IOL) implantation and wavefront-guided laser in situ keratomileusis (wfg-LASIK). Our prospective study comprised thirty eyes undergoing posterior chamber phakic IOL implantation and 30 eyes undergoing wfg-LASIK. We randomly measured visual acuity under myopic defocus after cycloplegic and non-cycloplegic correction. We also calculated the modulation transfer function by optical simulation and estimated visual acuity from Campbell &Green's retinal threshold curve. Visual acuity in the phakic IOL group was significantly better than that in the wfg-LASIK group at myopic defocus levels of 0, -1, and -2 D (p < 0.001, p < 0.001, and p = 0.02, Mann-Whitney U-test), but not at a defocus of -3 D (p = 0.30). Similar results were also obtained in a cycloplegic condition. Decimal visual acuity values at a myopic defocus of 0, -1, -2, and -3 D by optical simulation were estimated to be 1.95, 1.21, 0.97, and 0.75 in the phakic IOL group, and 1.39, 1.11, 0.94, and 0.71 in the wfg-LASIK group, respectively. From clinical and optical viewpoints, phakic IOL implantation was superior to wfg-LASIK in terms of the postoperative visual performance, even in the presence of low to moderate myopic regression.

Correction of moderate to high hyperopia with an implantable collamer lens: medium-term results

PURPOSE

To evaluate the medium-term results of phakic posterior chamber implantable collamer lens implantation to correct moderate and high hyperopia.

METHODS

In this retrospective study, patients were treated for hyperopia with the Visian Implantable Collamer Lens (ICH model V3; STAAR Surgical AG, Nidau, Switzerland). Examined parameters were manifest refraction spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, vault, anterior chamber depth, anterior chamber angle width, endothelial cell density, intraocular pressure, patient satisfaction, and complications.

RESULTS

The mean age of 15 patients (28 eyes) was 28 years (range: 18 to 36 years), with a mean follow-up period of 3.6 years (range: 3 to 6 years). The mean manifest refraction spherical equivalent decreased from +6.30 ± 1.42 diopters (D) (range: +4.25 to +8.50 D) preoperatively to -0.37 ± 0.56 D (range: -1.25 to +1.00 D) at 3 years postoperatively. The mean uncorrected distance visual acuity improved from 0.77 ± 0.38 logMAR (range: 0.16 to 1.30 logMAR) to 0.20 ± 0.17 logMAR (range: 0.00 to 0.48 logMAR) at the 3-year follow-up. Postoperatively, 62% of eyes gained one line of corrected distance visual acuity or remained unchanged. The mean vault reduced from 367.1 ± 253.6 μm (range: 70.0 to 1,190.0 μm) at 1 month postoperatively to 283.6 ± 210.0 μm (range: 75.0 to 915.0 μm) at the last follow-up visit (P = .005). The mean preoperative anterior chamber depth and anterior chamber angle width also decreased at the last follow-up visit (P = .037 and < .0001, respectively). The mean endothelial cell loss was 4.91% (P = .089). No serious complications occurred. Thirteen (87%) patients were satisfied with the outcomes and no patient was dissatisfied.

CONCLUSIONS

Implantation of a posterior chamber implantable collamer lens is a safe, effective, predictable, and stable method for the correction of moderate and high hyperopia in highly selected patients. No case of cataract or anterior subcapsular opacities formation was recorded in relation to the decrease of vault over the studied period and low vault in some eyes.

[Scheimpflug photography for the examination of phakic intraocular lenses]

BACKGROUND

High myopia phakic intraocular lenses (IOL) have become an established means of surgical correction for high ametropia. Scheimpflug photography is one of the methods which are frequently applied for postoperative examination of the implants.

MATERIAL AND METHODS

Results from published studies employing Scheimpflug photography for examination of anterior chamber angle-fixated, iris-fixated and sulcus-fixated phakic IOLs were evaluated.

RESULTS

In several published studies Scheimpflug photography was used to examine the position of the implant and opacification of the crystalline lens. The results provided valuable evidence for the improvement of phakic IOL design.

CONCLUSION

Scheimpflug photography offers an easy to use, rapid non-contact examination of phakic IOLs.

Factors influencing long-term regression after posterior chamber phakic intraocular lens implantation for moderate to high myopia

PURPOSE

To evaluate the factors affecting the long-term regression after posterior chamber phakic intraocular lens (Visian ICL; STAAR Surgical) implantation for myopia.

DESIGN

Retrospective observational case series.

METHODS

We retrospectively examined 60 eyes of 35 consecutive patients (age, 38.4 ± 9.3 years [mean ± standard deviation]) with myopic refractive errors of -4.00 to -15.25 diopters (D) undergoing ICL implantation. We assessed the amount of myopic regression from 1 month to 6 years after surgery. Stepwise multiple regression analysis was used to assess the factors affecting the amount of myopic regression.

RESULTS

The mean myopic regression from 1 month to 6 years after surgery was -0.33 ± 0.71 D (0.75 to -3.00 D). Explanatory variables relevant to the myopic regression were, in order of influence, patient age (partial regression coefficient B = -0.042, P < .0001) and preoperative axial length (B = -0.186, P = .013) (adjusted R(2) = 0.300). No significant correlation was seen with other clinical factors such as sex, preoperative refraction, intraocular pressure, white-to-white distance, anterior chamber depth, central corneal thickness, or mean keratometric readings.

CONCLUSIONS

Although the great majority of the variance remains unexplained, eyes of older patients and eyes with longer axial length are more predisposed to show greater myopic regression after ICL implantation. These results indicate that not only patient age but also axial length may play some role in predicting the long-term refractive outcomes of this surgical procedure.

Intraocular pressure during the early postoperative period after 100 consecutive implantations of posterior chamber phakic intraocular lenses with a central hole

PURPOSE

To study changes in intraocular pressure (IOP) during the early postoperative period in eyes having implantation of a posterior chamber phakic intraocular lens (pIOL) (Visian Implantable Collamer Lens V4c).

SETTING

Clínica Baviera, Instituto Oftalmológico Europeo, Madrid, Spain.

DESIGN

Case series.

METHODS

This retrospective review included the first consecutive eyes having implantation of a spherical or toric myopic pIOL with a central hole at Clínica Baviera from December 2011 to June 2012 by the same experienced surgeon. The IOP was evaluated preoperatively and 1 day, 1 week, and 1 month postoperatively.

RESULTS

The study comprised 100 eyes. The mean IOP changed from 14.6 mm Hg ± 3.4 (SD) (range 8 to 26 mm Hg) preoperatively to 14.5 ± 4.6 mm Hg (range 6 to 30 mm Hg) 1 day postoperatively, 14.2 ± 4.2 mm Hg (range 6 to 29 mm Hg) at 1 week, and 12.3 ± 3.4 mm Hg (range 9 to 24 mm Hg) at 1 month. No statistically significant changes were detected over time postoperatively (P>.2). No perioperative complications associated with the implantation of the pIOL were recorded. No pIOLs were explanted, no toric pIOL rotation was detected, and no pupillary block or acute angle closure was observed.

CONCLUSION

The short-term clinical data for the new pIOL model with the central hole (KS-Aquaport) suggest that it is a safe and effective means for controlling postoperative IOP.

Pediatric refractive surgery

This article reviews current thoughts regarding pediatric refractive surgery. This encompasses current trends in adult refractive surgery, differences between adult and pediatric refractive surgery, and future possibilities for refractive technology for the pediatric population.

Comparative study of 2 types of implantable collamer lenses, 1 with and 1 without a central artificial hole

PURPOSE

To compare the outcomes between implantable collamer lenses (ICLs), 1 with and 1 without a central artificial hole.

DESIGN

Comparative study.

METHODS

We included 65 eyes of 65 patients with refractive error in our study. The mean manifest refraction spherical equivalent (MRSE) was -9.32 ± 4.02 diopters (range, 6.75 to -16.50 diopters). We divided patients into 2 groups based on the type of ICL used, 1 for those without a central artificial hole (Group I, 21 eyes) and 1 for those with a hole (Group II, 44 eyes). The postoperative changes in visual acuity, endothelial cell density, MRSE, higher order aberrations readings, and objective scatter index between the 2 kinds of ICLs were compared. The follow-up period was 3 months.

RESULTS

There were no statistically significant differences in the postoperative changes in uncorrected distance visual acuity (P = 0.81), corrected distance visual acuity (P = 0.24), MRSE (P = 0.18), and endothelial cell density (P = 0.76) between the groups. Also, no difference in objective scatter index was found at 3 months (P = 0.32). None of the higher order aberrations readings showed any significant difference between the groups.

CONCLUSION

There were no significant differences between the outcomes of these ICLs, either with or without a central artificial hole.

Scheimpflug Analysis of Centration and Bending of Posterior Chamber Phakic Intraocular Lenses

PURPOSE

The aim of the study was to present a novel technique for the assessment of postoperative centration and bending in phakic intraocular lens (PIOL), illustrated through 4 patient examples.

DESIGN

This was a prospective observational study.

METHODS

Four patients (7 eyes) who presented with complaints of reduced quality of vision after implantation with a Staar Collamer plate haptic PIOL were recruited for assessment. Scheimpflug images were obtained and analyzed with respect to the apical axis and the crystalline lens by means of an in-house-developed algorithm. The program provides an estimate for the PIOL centration and bending through an analysis of the distance between the PIOL and the crystalline lens.

RESULTS

The algorithm detected PIOL bending in 5 of the 7 eyes and PIOL decentration in 3 eyes. The PIOL bending or decentration detected corresponded, in all cases, with the axis of the astigmatism-like complaints in the patient. In 2 eyes of the same patient, the analysis could not be performed because the distance between PIOL and crystalline lens was too short for reliable analysis.

CONCLUSIONS

This algorithm is a useful tool to objectively assess the postoperative complaints of patients implanted with a posterior chamber PIOL. Bending and decentration due to anatomical variations of the sulcus lens position can be measured and in many cases correlated with patients' complaints.

Eight-year follow-up of posterior chamber phakic intraocular lens implantation for moderate to high myopia

PURPOSE

To assess the long-term clinical outcomes of Implantable Collamer Lens (Visian ICL; STAAR Surgical) implantation for moderate to high myopia.

DESIGN

Retrospective observational case series.

METHODS

This study evaluated 41 eyes of 41 patients with myopic refractive errors of -4.00 to -15.25 diopters (D) who underwent ICL implantation and routine postoperative examinations. Before surgery, and 1 and 6 months and 1, 4 and 8 years after surgery, we assessed the safety, efficacy, predictability, stability, and adverse events of the surgery.

RESULTS

The safety and efficacy indices were 1.13 ± 0.27 and 0.83 ± 0.36. At 8 years, 68.3% and 85.4% of the eyes were within 0.5 and 1.0 D, respectively, of the targeted correction. Manifest refraction changes of -0.32 ± 0.73 D occurred between 1 month and 8 years. The mean endothelial cell loss from preoperative levels was 6.2% at 8 years. Two eyes (4.9%) developed clinically significant symptomatic cataract during the follow-up period. Simultaneous lens extraction and phacoemulsification with IOL implantation was successfully performed in these 2 eyes.

CONCLUSIONS

According to our experience, ICL implantation was overall good in measures of safety, efficacy, predictability, and stability for the correction of moderate to high myopia during the 8-year observation period, suggesting its long-term viability as a surgical option for the treatment of such eyes.

Macular hole after phakic intraocular lens implantation: two cases with divergent manifestations

Abstract We describe two cases of a macular hole (MH) which had divergent manifestations and clinical courses following implantation of an Implantable Collamer Lens (ICL) in two high myopic patients. The onset of symptoms and shape of the holes, which were observed by optical coherence tomography and fundoscopy, and prognosis of the visual acuity after the surgery of each patient, were quite different. In the first patient, the symptom was an acute onset. Fundoscopy showed a cuneiform-shaped hole with internal limiting membrane defect around the hole. The prognosis after the surgery was very poor, and the best corrected visual acuity was 0.08 after complete anatomical closure. In another patient, the MH showed insidious progression with disease-free interval from ICL implantation to MH onset. After the surgery, the best corrected visual acuity was recovered to 1.0.

ICL versus Veriflex phakic IOL for treatment of moderately high myopia: randomized paired-eye comparison

PURPOSE

To compare the objective and subjective outcome of implantable collamer lenses (ICLs; Staar Surgical, Monrovia, CA) versus Veriflex lenses (AMO, Santa Ana, CA) for the correction of moderately high myopia.

METHODS

A prospective randomized comparative eye study was performed on 24 patients with bilateral myopia that ranged from -6 to -14.5 diopters (D). One eye was implanted with an ICL and the other eye was implanted with a Veriflex phakic intraocular lens (PIOL). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), higher-order aberrations (HOAs), contrast sensitivity, patient satisfaction, central endothelial cell count, and PIOL centration were determined 6 months after surgery

RESULTS

The logMAR UDVA and CDVA improved significantly in both groups (P < .001). There was no statistically significant difference in postoperative logMAR UDVA (P = .41) or logMAR CDVA (P = .36) between the two groups. Postoperative deviation from target refraction was -0.06 ± 0.41 D in the ICL group and -0.07 ± 0.49 D in the Veriflex group (P = .15). The difference in both induced and absolute postoperative HOAs between groups was not statistically significant. The area under the log contrast sensitivity function increased significantly in both groups postoperatively. The difference in patient satisfaction between both PIOLs was not statistically significant. A higher but statistically insignificant central endothelial cell count loss occurred in the Veriflex group (P = .11).

CONCLUSION

Both ICL and Veriflex PIOLs have equally satisfactory objective and subjective visual outcomes after surgery.

Outcome of posterior chamber phakic intraocular lens procedure to correct myopia

PURPOSE

To assess the safety and efficacy of the implantable contact lens (ICL™) to treat myopia.

DESIGN

Clinical, retrospective, single center, non-randomized case series.

PARTICIPANTS

Sixty-nine eyes of 46 patients with myopia ranging from -3.00 to 25.00 D were included in this study.

INTERVENTION

Implantation of the ICL™.

MAIN OUTCOME MEASURES

Uncorrected Visual Acuity (UCVA), refraction, best spectacle corrected visual acuity (BSCVA), adverse events, operative and postoperative complications, subjective assessment and symptoms.

RESULTS

The mean follow-up was 12.35 ± 6.13 (SD) months (range, 6 months-32 months). At the last visit, 49.20% of eyes had 20/20 or better UCVA compared to preoperative 20/20 or better BSCVA of 31.9% of eyes; 69.23% of eyes had postoperative UCVA better than or equal to preoperative BSCVA. The mean manifest refractive cylinder was 1.93 ± 1.21 D at baseline and 1.00 ± 0.92 D postoperatively. The mean manifest refraction spherical equivalent (MRSE) was -11.70 ± 4.24 D preoperatively and -0.69 ± 1.13 D postoperatively. A total of 69.8% of eyes were within ±0.5 D of the predicted MRSE; 84.1% were within ±1.0 D, and 88.90% were within ±2.0 D. BSCVA of 20/20 or better was achieved in 64.6% of eyes postoperatively, compared to 31.9% preoperatively. Mean improvement in BSCVA was 1line. One eye (1.5%) lost ⩾2 lines of BSCVA at the last visit, whereas 20% of eyes improved by ⩾2 lines. A total of 56.92% of cases gained ⩾1 line of BSCVA and 4.62% of cases lost ⩾1 line. Four ICL lenses were removed without significant loss of BSCVA, and 2 eyes with clinically significant lens opacities were observed. Four eyes (5.8%) developed a pupillary block the first day postoperatively. One eye (1.4%) developed a hypotony and AC shallowing.

CONCLUSION

Implantation of ICL for the correction of myopia was a safe procedure with good visual and refractive results from the early postoperative period to 1 year. Long-term follow-up is required to confirm the long-term safety of this implant.

Posterior chamber phakic intraocular lens to correct myopia: long-term follow-up

PURPOSE

To evaluate the long-term safety and efficacy of a refractive phakic intraocular lens (pIOL) (PRL) to correct moderate to high myopia.

SETTING

Department of Ophthalmology, University Medicine Charité Berlin, Berlin, Germany.

DESIGN

Retrospective cohort study.

METHODS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure, endothelial cell loss, and adverse events were evaluated.

RESULTS

The study enrolled 53 eyes (mean spherical equivalent [SE] -12.17 diopters [D] ± 4.12 [SD]) of 29 patients. The mean age was 34.6 ± 9.2 years and the mean follow-up, 86 ± 21.2 months. The mean UDVA improved from 1.37 ± 0.28 logMAR preoperatively to 0.14 ± 0.19 logMAR at the last postoperative visit (P<.05). The mean CDVA improved from 0.10 ± 0.18 logMAR to -0.01 ± 0.09 logMAR (P<.05). The overall mean efficacy index and mean safety index were 0.9 and 1.21, respectively, at the last follow-up visit. The mean endothelial cell loss at the last follow-up was 6.4%. The complications were slight posterior chamber (PC) pIOL decentration (5 eyes, 9.4%), severe PC pIOL decentration resulting in pIOL removal (1 eye, 1.8%), glaucoma (4 eyes, 7.5%), clinically significant cortical lens opacification resulting in cataract surgery (4 eyes, 7.5%), clinically asymptomatic anterior subcapsular cataract formation (6 eyes, 11.3%), and retinal detachment (2 eyes, 3.8%).

CONCLUSIONS

Posterior chamber phakic pIOL implantation to correct moderate to high myopia provided predictable and stable refractive results but with a high rate of serious complications over the long term.

FINANCIAL DISCLOSURE

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

Three-year follow-up of posterior chamber toric phakic intraocular lens implantation for moderate to high myopic astigmatism

PURPOSE

To assess the 3-year clinical outcomes of toric phakic intraocular lens (Visian ICL™; STAAR Surgical) implantation for moderate to high myopic astigmatism.

METHODS

This retrospective study evaluated fifty eyes of 28 patients who underwent toric ICL implantation for the correction of moderate to high myopic astigmatism and who regularly returned for postoperative examination. Before, and 1, 3, and 6 months after, and 1, 2, and 3 years after surgery, we assessed the safety, efficacy, predictability, stability, and adverse events of the surgery in eyes undergoing toric ICL implantation.

RESULTS

The logarithm of the minimal angle of resolution (LogMAR) uncorrected visual acuity and LogMAR best spectacle-corrected visual acuity were -0.10 (corresponding to Snellen equivalents 20/16) ± 0.16 and -0.20 (corresponding to 20/12.5) ± 0.07, 3 years postoperatively, respectively. The safety and efficacy indices were 1.16 ± 0.20 and 0.94 ± 0.28. At 3 year, 82% and 98% of the eyes were within 0.5 and 1.0 D, respectively, of the targeted correction. Manifest refraction changes of -0.15 ± 0.31 D occurred from 1 month to 3 year. No vision-threatening complications occurred during the observation period.

CONCLUSIONS

On the basis of the clinical results of this study, toric ICL implantation was good in all measures of safety, efficacy, predictability, and stability for the correction of moderate to high myopic astigmatism throughout a 3-year observation period.

Intraindividual comparison of visual performance after posterior chamber phakic intraocular lens with and without a central hole implantation for moderate to high myopia

PURPOSE

To compare postoperative visual performance after implantable Collamer lenses with and without a central hole (Hole ICL and conventional ICL) are implanted to correct moderate to high myopia.

DESIGN

Prospective intraindividual comparative study.

PATIENTS AND METHODS

This study evaluated 58 eyes of 29 patients with spherical equivalents of -7.55 ± 2.09 diopters (D) [mean ± standard deviation] who underwent Hole ICL implantation in one eye and conventional ICL implantation in the other eye by randomization assignment. Ocular higher-order aberrations (HOAs) and contrast sensitivity (CS) function were measured by Hartmann-Shack aberrometry and a contrast sensitivity unit before and 3 months after surgery, respectively. From the contrast sensitivity, the area under the log CS function was calculated.

RESULTS

For 4-mm and 6-mm pupils, the changes after Hole ICL implantation in coma-like aberrations, spherical-like aberrations, and total HOAs are similar to those after conventional ICL implantation (P > .05, Wilcoxon signed rank test). The postoperative area under the log CS function was significantly increased after Hole ICL implantation (P < .05), and was equivalent to that after conventional ICL implantation under photopic, mesopic, or mesopic with glare conditions. Subjective symptoms such as glare or halo were also essentially equivalent after Hole ICL and conventional ICL implantation.

CONCLUSIONS

A newly developed Hole ICL implantation appears to be equivalent in the induction of HOAs and CS function to conventional ICL implantation for the correction of moderate to high myopia, suggesting its viability as a surgical option for the treatment of such eyes, because it does not require additional peripheral iridotomies and may also reduce the risk of cataract formation.

Visual performance after posterior chamber phakic intraocular lens implantation and wavefront-guided laser in situ keratomileusis for low to moderate myopia

PURPOSE

To compare postoperative visual function after implantable collamer lens (ICL) implantation and after wavefront-guided laser in situ keratomileusis (LASIK) in eyes with low to moderate myopia.

DESIGN

Retrospective observational case study.

PATIENTS AND METHODS

We investigated 30 eyes of 20 patients undergoing ICL implantation and 64 eyes of 38 patients undergoing wavefront-guided LASIK for the correction of low to moderate myopia (manifest spherical equivalent: -3.00 to -5.88 diopters [D]). Ocular higher-order aberrations (HOAs) and contrast sensitivity (CS) function were measured by Hartmann-Shack aberrometry and a contrast sensitivity unit before and 3 months after surgery, respectively. From the contrast sensitivity, the area under the log contrast sensitivity function was calculated.

RESULTS

For 4-mm and 6-mm pupils, the changes in ocular third-order aberrations, fourth-order aberrations, and total HOAs after ICL implantation were significantly less than those after wavefront-guided LASIK (P < .05, Mann-Whitney U test). The postoperative area under the log contrast sensitivity function was significantly increased after ICL implantation (P < .001), whereas, after wavefront-guided LASIK, it was not significantly changed (P = .11).

CONCLUSIONS

ICL implantation induces significantly fewer ocular HOAs than wavefront-guided LASIK. Moreover, CS was significantly improved after ICL implantation but unchanged after wavefront-guided LASIK in eyes with low to moderate myopia. Thus, even in the correction of low to moderate myopia, ICL implantation appears to be superior in visual performance to wavefront-guided LASIK, suggesting that it may be a viable surgical option for the treatment of such eyes.

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.

Long-term results of phakic refractive lens implantation in eyes with high myopia

PURPOSE

To evaluate the long-term results of phakic refractive lens (PRL; Carl Zeiss Meditec) implantation in eyes with high myopia.

METHODS

In this retrospective, noncomparative, interventional case series, 143 myopic eyes of 82 patients were treated for high myopia with the implantation of the silicone PRL in the posterior chamber.

RESULTS

Mean follow-up was 3.8±1.7 years (range: 1 to 6 years). Six years postoperatively (n=34), a statistically significant reduction was noted in the cycloplegic spherical equivalent from -14.08±4.00 diopters (D) (range: -24.88 to -4.75 D) before PRL implantation to -0.45±0.62 D (range: -1.00 to 1.00 D) (P<.001). At 6 years, 67.6% (23 eyes) and 91.2% (31 eyes) were within ±0.50 and ±1.00 D of target refraction, respectively. Mean logMAR uncorrected and corrected distance visual acuity improved significantly (P<.001) (counting fingers preoperatively in all eyes to 0.17±0.15 [range: 0.54 to -0.06] and 0.19±0.19 [1.00 to -0.08] to 0.07±0.10 [range: 0.30 to -0.10], respectively). Complications included anterior capsule damage (3 eyes), temporary intraocular pressure increase (14 eyes), pigment dispersion (1 eye), and PRL decentration (1 eye). No eyes presented any signs of cataract up to 6 years postoperatively.

CONCLUSIONS

Long-term results show that PRL implantation is an effective and safe method for treating high myopia.