Collamer intraocular contact lens to correct high myopia

Evaluation of biometric indicators of anterior segment parameters after ICL implantation by swept-source optical coherence tomography

BACKGROUND

To evaluate anterior segment structural alterations after implantable collamer lens (ICL) implantation in myopic patients using swept-source quantitative optical coherence tomography (SS-OCT).

METHODS

This prospective study included 47 eyes in 24 patients with preoperative spherical equivalent ≥ -3.00 D. Patients underwent ICL implantation at Department of Ophthalmology, Peking University Third Hospital, from May 2021 to December 2022. SS-OCT was used to measure anterior chamber width (ACW), angle opening distance (AOD), angle recess area (ARA), trabecular-iris area (TISA), trabecular-iris angle (TIA), iridotrabecular contact (ITC) area, and ITC Index before ICL implantation surgery and at 1 month follow-up. The correlations among the ITC index, vault, and angle parameters were analysed. Receiver operating characteristic (ROC) analysis was used to explore the ability of the vault to identify eyes with suspected angle-closure.

RESULTS

At one month following ICL implantation, the ITC area was 0.396 ± 0.37 mm², and the ITC index is 8.143 ± 5.439%. All angle parameters, except ACW, showed a statistically significant reduction on SS-OCT (P < 0.05). Mean AOD500, AOD750, ARA500, ARA750, TISA500, TISA750, TIA500, and TIA750 values at one month postoperatively decreased by 60.0%, 60.4%, 58.1%, 59.2%, 57.3%, 58.7%, 48.8%, and 50.7%, respectively. The vault was positively correlated with the ITC index and percent change in anterior chamber angle parameters. A vault of > 0.659 mm was found to be optimal for angle-closure suspect with a sensitivity of 85.2% and a specificity of 53.9%.

CONCLUSIONS

Anterior chamber angle parameters decreased one month after ICL implantation, and their percentage changes and ITC index correlated with the vault. When the vault is larger than 0.659 mm, it is necessary to be alert to possible closed angle suspicion.

Prospective clinical study of retinal microvascular alteration after ICL implantation

Purpose: To evaluate the retinal microvascular alteration after implantable collamer lens (ICL) implantation in moderate to high myopia patients using quantitative optical coherence tomography angiography (OCTA). Methods: This prospective cohort study included 50 eyes of 25 patients with preoperative spherical equivalent ≥ -3.00 D. Patients underwent bilateral ICL implantation at the Department of Ophthalmology, Peking University Third Hospital, from November 2018 to July 2019. OCTA was used to image the superficial and deep retinal capillary plexuses before ICL implantation surgery and at 3 months follow-up. Results: There was no significant difference in the microvascular density within each annular zone and all quadrantal zones of the superficial and deep layers found in myopia patients before and after ICL surgery. Conclusion: Levels of microvascular density in retinal capillary plexuses were stable, as detected by the OCTA, showing the high security of ICL implantation, which would not leave adverse effects on retinal microvasculature in myopia patients.

Intraocular Implantable Collamer Lens with a Central Hole Implantation: Safety, Efficacy, and Patient Outcomes

This review summarizes the available literature and provides updates on the efficacy, safety, and patient outcomes of phakic intraocular lens implantation using implantable collamer lens (ICL), with a focus on newer models with a central port (EVO/EVO+ Visian Implantable Collamer Lens, STAAR Surgical Inc.). All studies included in this review were identified from the PubMed database and were reviewed for relevancy of their topic. Data on hole-ICL implantation performed between October 2018 and October 2022 in 3399 eyes showed a weighted average efficacy index of 1.03 and a weighted average safety index of 1.19 within an average follow-up of 24.7 months. The incidence of complications such as elevated intraocular pressure, cataract, and corneal endothelial cell loss was low. Moreover, both quality of vision and quality of life improved after ICL implantation, confirming the benefits of this procedure. In conclusion, ICL implantation is a promising refractive surgery alternative to laser vision correction with excellent efficacy, safety, and patient outcomes.

Comparison of accommodation and accommodative micro-fluctuation after implantable collamer lens and LASIK surgery for myopia

BACKGROUND

To longitudinally analyze and compare the accommodative micro-fluctuation (MFs) and accommodative function between myopic patients after implantable collamer lens (ICL) implantation and laser in situ keratomileusis (LASIK).

METHODS

Patients with good corrected visual acuity (20/20 or better) and underwent ICL (V4c) and LASIK for myopic-correction (ranging from - 3.50 to - 8.50 D) were recruited. Refraction, amplitude of accommodation (AMP), accommodative lag, higher-order aberration (HOA), and MFs were recorded before surgery and 1 and 3 months after surgery. The ACOMEREF automatic refractor was used to measure the high-frequency component (HFC) of the MFs, which suggested tension of the ciliary muscle.

RESULTS

The study comprised 120 eyes. At 3 months after surgery, the manifest refractive spherical equivalent of the ICL and LASIK groups were - 0.11 and - 0.09 D, respectively (p = 0.46). HFC values were significantly higher at 1 month (p = 0.03) and 3 months postoperatively (p = 0.03) in the ICL group compared to that in the LASIK group. The ocular HOA of the ICL group was 1.08 ± 0.43 μm, which was lower than the LASIK group 1.45 ± 0.54 μm (p = 0.01). No significant differences in AMP and accommodative lag between groups were noted at 3 months postoperatively. There was a positive correlation between HFC and vault of the ICL lens (r² = 0.14, p = 0.005). There were no correlations between HFC and ocular HOA and postoperative MRSE in the two groups (all p>0.05).

CONCLUSIONS

The HFC increased significantly after an early period of ICL implantation compared to laser in situ keratomileusis for myopic correction, which indicated increased tension of the ciliary muscle, and had a positive correlation on the vault of the ICL lens; However, studies with longer follow-up time and more structural evaluation are needed.

Reasons for explantation of phakic intraocular lenses and associated perioperative complications: cross-sectional explant registry analysis

Background

We discuss the safety, since their introduction, of phakic intraocular lenses (pIOLs) to correct refractive errors in healthy eyes. We investigated the reasons for pIOL explantation and the associated perioperative complications.

Methods

This retrospective, cross-sectional study included 69 pIOLs, explanted at a single tertiary center between July 2005 and March 2020: 34 angle-supported (G1), 28 iris-fixated (G2) and seven posterior chamber (G3) pIOLs. Case data including the reason for explantation was taken from the patient records. Intra- and postoperative complications were evaluated for an association with the pIOL.

Results

The mean duration in the eye was 10.4 (0.2–28) years. Cataractogenesis and subsequent surgery that required pIOL explantation was the reason in 42% of all cases. In 22%, cataract in combination with endothelial damage prompted explantation, with 26, 18 and 14% for G1, G2 and G3 respectively. The second most common reasons were corneal damage alone in the angle-supported group (26%), IOL subluxation in the iris-fixated group (18%), and photopic disturbance in the posterior chamber group (29%). In 68% of all explantations, the surgical course was unremarkable, while in the remaining cases perioperative complications were associated with the lens in 45.7%.

Conclusion

Overall, the need for cataract surgery was the most common reason for pIOL explantation. Corneal complications were more frequent in the angle-supported pIOLs and their removal was associated with higher rates of complication compared to the other groups.

Long-term In Vivo Stability of Posterior Chamber Phakic Intraocular Lens: Properties and Light Transmission Characteristics of Explants

PURPOSE

To evaluate the in vivo durability of the surface and optical properties of the implantable Collamer lens (ICL).

DESIGN

Retrospective case series.

METHODS

We included patients who developed cataracts after having undergone ICL implantation from March 2003 to May 2014 and underwent ICL explantation followed by cataract surgery from March 2017 to December 2019 at the Nagoya Eye Clinic. ICL explants were submitted to Chukyo Medical Co, Ltd (Nagoya City, Japan) for laboratory analysis using ultraviolet-visible light spectroscopy, light microscopy (LM), and scanning electron microscopy. Patients' demographic and clinical data were collected and reviewed.

RESULTS

Thirteen eyes from 10 patients were studied. The average age at ICL explantation was 50.5 ± 8.5 years (range, 34.5-66.3 years). The average length of ICL stay in the eye (from implantation to explantation) was 10.5 ± 2.7 years (range, 4.4-13.7 years). No opacification or coloring of the ICL explants was observed by LM. The ICL explants showed almost the same light transmittance as that of unused ICLs. Scanning electron microscopy revealed no irregularities at the surface of the center and periphery of the optic and haptic footplate. The positioning holes did not show any deposition.

CONCLUSION

The ICLs remained in-eye for >10 years without any deterioration in the surface and optical properties of the ICL, despite their contact with the ciliary body and iris tissues and the continuous interaction with the aqueous humor components. The present study shows long-term in vivo stability of the ICL.

Safety of the Minimum Ophthalmic Viscosurgical Device Technique in Phakic Implantable Collamer Lens Implantation

PURPOSE

To compare the safety of the minimum ophthalmic viscosurgical device (OVD) technique with the standard procedure in phakic Visian Implantable Collamer Lens (ICL) (STAAR Surgical AG, Nidau, Switzerland) implantation.

METHODS

This retrospective cohort study evaluated a total of 147 eyes of 74 patients who underwent ICL implantation with the minimum OVD technique (minimum OVD group) and 154 eyes of 77 patients with the standard procedure (standard OVD group). Intraoperative and postoperative complications were recorded. Preoperative and postoperative visual acuity, intraocular pressure (IOP), aqueous depth (AQD), and central corneal endothelial cell density (ECD) were collected and analyzed over the 12-month follow-up. Lens vault and occurrence of paracentesis after surgery were also recorded.

RESULTS

No intraocular complications were observed. No difference was found in visual outcomes, lens vault, and AQD at all time points between the two groups (P > .05). The minimum OVD group had significantly lower IOP than the standard OVD group at 2 hours (17.04 ± 4.21 vs 19.40 ± 6.78 mm Hg, P < .001) and 3 hours (15.12 ± 3.38 vs 17.15 ± 5.09 mm Hg, P < .001) postoperatively. The IOP gradually returned to the preoperative level after 24 hours postoperatively. The occurrence rate of paracentesis was significantly less in the minimum OVD group compared with the standard group (0.68% [1 of 147] vs 3.2% [5 of 154], P < .001). ECD was not significantly different between groups at all time points (P > .05).

CONCLUSIONS

The minimum OVD technique could achieve visual and structural outcomes comparable to the standard procedure without additional damage to the corneal endothelial cells, while reducing the IOP fluctuations after surgery. [J Refract Surg. 2020;36(1):42-48.].

Off-Label Use of Phakic Intraocular Lens with a "Piggyback" Technique

Purpose

We report a case of a highly myopic pseudophakic patient who received off-label placement of a phakic intraocular lens (pIOL) via a “piggyback” technique, allowing the placement of an intraocular lens (IOL) in his fellow eye, resulting in improved visual acuity and emmetropia.

Case Report

A 66-year-old, highly myopic, pseudophakic male with an IOL implant in his left eye was referred for second opinion for surgical options for his phakic right eye. Given the severe myopic status of both eyes, he received off-label placement of a posterior chamber pIOL with a piggyback technique for the pseudophakic left eye followed by standard cataract surgery and intraocular lens implantation in the right eye. For the left eye, uncorrected best visual acuity improved from 20/70 to 20/25.

Conclusion

This case demonstrates the successful off-label use of a phakic IOL in a pseudophakic, highly myopic patient with a piggyback technique, resulting in improved visual acuity and ultimately allowing IOL placement in the fellow eye for emmetropia. This off-label use of pIOL can offer ophthalmologists an alternative option for pseudophakic patents with severe refractive error.

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.

Management of pseudophakic myopic anisometropic amblyopia with piggyback Visian® implantable collamer lens

PURPOSE

To assess the outcomes of sulcus implantation of the Visian^® implantable collamer lens (ICL) to correct pseudophakic myopic anisometropic amblyopia with myopic shift and/or primary refractive overcorrection.

METHODS

Prospective case series enrolled 14 pseudophakic eyes of 14 patients, 5-9 years old, with history of cataract surgery and primary in the bag-intraocular lenses (IOL) implantation, followed by myopic shift and/or refractive overcorrection and anisometropic amblyopia of variable degrees. All cases had implantation of a piggyback ICL/toric ICL, to correct the myopia/myopic astigmatism. Preoperatively, we evaluated the uncorrected distance visual acuity (UCVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), intraocular pressure (IOP) and endothelial cell density (ECD). We assessed the position and vaulting of the ICLs on slit lamp examination and confirmed by Scheimpflug tomography. Postoperative follow-up was at 1st week and 1, 3, 6, 9, 12, 18 and 24 months.

RESULTS

Uncorrected distance visual acuity improved in all cases, and CDVA improved in 11 amblyopic eyes (2-4 lines). There was no evidence of interlenticular opacification (ILO) throughout the 2-year follow-up. Two cases were complicated with early postoperative acute elevation of IOP and were controlled with topical beta-blockers. Postoperative acute anterior uveitis occurred in six eyes and controlled by topical steroids. Implantable collamer lens (ICL) vault was measured using Pentacam, with mean value of 470 ± 238 μm.

CONCLUSION

Sulcus implantation of the secondary piggyback ICL to correct unilateral pseudophakic myopic refractive error in children was safe, efficient, predictable and well tolerated in management of anisometropic amblyopia in all eyes.

Intraocular pressure after implantation of the Visian Implantable Collamer Lens With CentraFLOW without iridotomy

PURPOSE

To compare the intraocular pressure (IOP) values during a 3-month period after implantation of the new Visian Implantable Collamer Lens (ICL; STAAR Surgical Company, Nidau, Switzerland) V4c design with CentraFLOW technology without iridotomy using a standard procedure followed by implantation of the conventional ICL V4b model.

DESIGN

Retrospective cohort study.

METHODS

This study included 17 eyes implanted with the ICL V4b model and 18 eyes implanted with the ICL V4c model. The mean preoperative spherical equivalent refractions were -7.48 ± 5.00 diopters and -8.66 ± 4.2 diopters, respectively. We compared the best-corrected distance visual acuity before surgery with the uncorrected distance visual acuity after surgery. The intraocular pressure (IOP) was measured 1 week, 1 month, and 3 months after surgery. The central vault at 3 months was measured using optical coherence tomography.

RESULTS

Three months after surgery, the mean uncorrected distance visual acuities were -0.09 ± 0.12 logarithm of the minimal angle of resolution units with the V4b and -0.07 ± 0.11 logarithm of the minimal angle of resolution units with the V4c. The mean distances between the ICL and the anterior crystalline lens surface were 557 ± 224 μm and 528 ± 268 μm for the V4b and V4c, respectively (P = .73). After 1 week and 1 month, the mean IOPs were 13.7 and 13.3 mm Hg and 14.7 and 15.1 mm Hg, respectively. There were no significant differences in IOP within or between groups during the follow-up period (P > .05, for all comparisons).

CONCLUSIONS

The new ICL with the CentraFLOW design seems to provide similar results as its predecessors for the correction of moderate to high myopia and maintenance of safe IOP levels without iridotomy.

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.

Optimization of an implantable collamer lens sizing method using high-frequency ultrasound biomicroscopy

PURPOSE

To develop and evaluate a new implantable collamer lens (ICL) sizing method that uses high-frequency ultrasound biomicroscopy (UBM).

DESIGN

Interventional case series.

METHODS

ICL were implanted in 47 eyes of 25 patients (8 male, 17 female, mean age 34.7±6.8 years). At 3 months after ICL surgery, the vault (distance between ICL and crystalline lens) was measured using anterior optical coherence tomography (OCT). Stepwise multiple regression analysis was performed in order to determine the optimal ICL size that will be expected to achieve a 0.5-mm vault, and the regression equation was calculated. Mean keratometric power, axial length, anterior chamber depth, sulcus-to-sulcus (STS) diameter, and distance between STS plane and crystalline lens were applied as candidates for explanatory variables. Subsequently, the equation was applied to a new group of patients (81 eyes of 43 patients, 20 male and 23 female, mean age 35.6±7.2 years) in order to decide the ICL size. Postoperative vault was evaluated at 3 months after surgery. Main outcome measures were mean postoperative vault and percentages of eyes that achieved moderate vault.

RESULTS

The regression equation was determined using 3 explanatory variables: anterior chamber depth (ACD), STS diameter, and distance between STS plane and anterior crystalline lens surface (STSL). The mean vault error (postoperative vault-predicted vault) was -0.06±0.29 mm. Of the total number of eyes, 88.9% had a vault between 0.15 and 1.0 mm. None of the eyes had a low vault (<0.15 mm). Nine eyes (11.1%) had a high vault (>1.0 mm).

CONCLUSION

A novel ICL sizing equation was developed and shown to be an effective method for calculation of the optimal ICL size in order to achieve an appropriate vault.

Factors affecting rotation of a posterior chamber collagen copolymer toric phakic intraocular lens

PURPOSE

To evaluate the correlation between postoperative rotation of the toric Implantable Collamer Lens phakic intraocular lens (pIOL) and associated factors.

SETTING

Nagoya Eye Clinic, Nagoya, Japan.

DESIGN

Case series.

METHODS

The toric pIOL axis was analyzed by calculating the ocular internal cylinder power and axis from the total refractive cylinder and corneal astigmatism using vector analysis (Jaffe and Clayman method). The correlation between the toric pIOL rotation over 6 months postoperatively and the associated factors (ie, age, preoperative manifest refractive sphere, preoperative manifest spherical equivalent, mean keratometric power, axial length, toric pIOL intraoperative fixation angle, postoperative toric pIOL vault [distance between toric pIOL and anterior surface of crystalline lens], toric pIOL spherical power) were evaluated.

RESULTS

The mean age of the 34 patients (58 eyes) was 35.7 years ± 6.5 (SD). The mean rotation 6 months postoperatively was 4.82 ± 6.98 degrees (range 0.0 to 47.2 degrees). The intraoperative toric pIOL fixation angle and postoperative toric pIOL rotation were significantly correlated (Spearman rank correlation: P=.0096 and R(2) = 0.1140; multiple logistic regression analysis: P=.009). In the 1 eye with significant rotation (47.2 degrees), the toric pIOL was exchanged for a larger toric pIOL.

CONCLUSIONS

A small toric pIOL rotation occurred during the 6-month follow-up. One cause of rotation could be the intraoperative fixation angle of the toric pIOL. A toric pIOL with a minimum intraoperative fixation angle should be used to prevent postoperative rotation.

Astigmatism correction: Laser in situ keratomileusis versus posterior chamber collagen copolymer toric phakic intraocular lens implantation

PURPOSE

To compare the stability and predictability of astigmatism correction between toric phakic intraocular lens (pIOL) implantation and laser in situ keratomileusis (LASIK).

SETTING

Nagoya Eye Clinic, Nagoya, Japan.

DESIGN

Comparative case series.

METHODS

Consecutive patients who had Implantable Collamer Lens pIOL implantation or LASIK were divided into 3 subgroups according to the amount of refractive cylinder correction (low, 0.00 to 1.25 diopters [D]; moderate, 1.50 to 2.75 D; high, ≥ 3.00 D). Manifest refraction was measured preoperatively and 1, 3, 6, and 12 months postoperatively. Based on these data, the predictability and stability of the refractive cylinder correction, error of the refractive cylinder correction, and error of the refractive cylinder correction axis were evaluated.

RESULTS

The study comprised 338 eyes (196 patients) in the toric pIOL group and 351 eyes (202 patients) in the LASIK group. In the moderate cylinder subgroup, more eyes were corrected within ± 0.50 D of the postoperative refractive cylinder in the LASIK group (132 eyes [91%]) than in the toric pIOL group (111 eyes [79%]). In the high refractive cylinder subgroup, the error of the refractive cylinder correction in the LASIK group was significantly higher than in the toric pIOL group (P=.032). The postoperative manifest refractive cylinder did not change in either group during the follow-up period.

CONCLUSIONS

The stability of the refractive cylinder after toric pIOL implantation was as high as after LASIK. Although predictability in the LASIK group was higher than in the toric pIOL group in eyes with moderate refractive cylinder, the toric pIOL group had higher predictability than the LASIK group in eyes with high refractive cylinder.

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.

Long-term follow-up of first-generation posterior chamber phakic intraocular lens

We present a patient who received a first-generation posterior chamber phakic intraocular lens (PC pIOL) (Fyodorov IOL) to correct myopia 18 years previously. After a long lapse in the follow-up, the patient presented with a reduced endothelial cell count. Although the cataractogenic effect of first-generation PC pIOLs is well known, no sign of cataract was present. The patient was totally satisfied even after 18 years. To our knowledge, this is the first report of a long follow-up of a patient implanted with a first-generation PC pIOL.

Spherical implantable collamer lenses for myopia and hyperopia: 126 eyes with 1-year follow up

BACKGROUND

To report on 1-year follow up of a series of 126 eyes implanted with a spherical implantable collamer lens (ICL).

METHODS

Retrospective case note review of 126 eyes (68 patients) undergoing ICL placement by a single surgeon (TG) to correct preoperative mean spherical equivalents between +8.88 and -20.50 D. Main outcome measures included uncorrected visual acuity (UCVA), refraction, best spectacle-corrected VA, unaided binocular vision, adverse events, operative/postoperative complications and patient symptoms.

RESULTS

Complete data were available at 1 year on 121 of the 126 eyes (65 out of 68 patients). At 12 months 86% (104/121) had postoperative UCVA better than or equal to preoperative best spectacle-corrected VA, and 98% (118/121) had UCVA within one line of preoperative best spectacle-corrected VA. Ninety-six per cent (116/121) had postoperative UCVA of 6/9 or better, and 100% had postoperative best-corrected visual acuity of 6/12 or better. Ninety-eight per cent (64/65) patients had unaided binocular vision at 1 year of 6/7.5 or better. Average myopia treated was -8.83 D (116 patients), and average hyperopia +7.14 D (10 patients). Two ICLs were replaced because of high vaulting; one eye had increased intraocular pressure that resolved with smaller ICL placement. Four patients had visually insignificant pigment deposits on the ICL at 3/12, but no pigmentary glaucoma. Five patients noticed haloes around lights at night, none preventing driving.

CONCLUSIONS

One-year results from this study, the largest reported clinical investigation of the use of ICLs in New Zealand, support the safety, efficacy and predictability of ICL to treat both hyperopic and myopic spherical refractive errors.

Correction of residual refractive error in pseudophakic eyes with the use of a secondary piggyback toricImplantable Collamer Lens

PURPOSE

To evaluate the feasibility of piggyback insertion with a toric Implantable Collamer Lens (ICL, STAAR Surgical).

METHODS

This study investigated eight pseudophakic eyes of five patients who underwent piggyback insertion of a toric ICL to correct residual refractive error. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refractive sphere and astigmatism were measured before and 6 months after surgery.

RESULTS

Pre- and 6-month postoperative logMAR UDVA were 0.759±0.430 and 0.201±0.458, respectively. All eyes were corrected within ±0.50 diopters (D) of intended spherical equivalent refraction. The manifest refractive astigmatism was within ±0.50 D in five (62.5%) eyes and ±1.00 D in seven (87.5%) eyes. No eyes lost more than one line of CDVA. Pupillary block occurred in one eye on postoperative day 1.

CONCLUSIONS

Piggyback insertion of a toric ICL appears to be effective and predictable in correcting refractive error in pseudophakic eyes.

Long-term changes in posterior chamber phakic intraocular collamer lens vaulting in myopic patients

OBJECTIVE

Evaluation of central and midperipheral vaulting of the posterior chamber phakic intraocular Collamer lens (ICL; Staar Surgical Inc., Monrovia, CA) in eyes with moderate to high myopia.

DESIGN

Retrospective analysis of prospectively collected data.

PARTICIPANTS

Eighty-four eyes treated with the latest ICL (V4 model) and 27 eyes treated with early ICL models were examined.

METHODS

After standardized ICL implantation, patients underwent complete ophthalmologic examinations before surgery and at 1 week, 1 month, 3 months, 6 months, and at yearly intervals thereafter. Central vaulting was measured using the Jaeger device (Haag-Streit, Bern, Switzerland). From 2006 onward, vaulting was measured additionally by optical coherence tomography (Visante OCT; Carl Zeiss Meditec, Jena, Germany). Using the Visante OCT, the crystalline lens rise and the midperipheral vaulting of the ICL were assessed.

MAIN OUTCOME MEASURES

Central vaulting after ICL implantation.

RESULTS

The mean duration of follow-up was 74.1+/-23.1 months and 96.3+/-50.2 months in eyes treated with V4 and early models, respectively. Postoperative central vaulting was 466+/-218 microm (range, 30-900 microm) in eyes treated with the V4 models and 321+/-200 microm (range, 150-900 microm) in those treated with early ICL models. From the 6-month follow-up onward, a continuous and nearly linear reduction of central vaulting was observed. At the 10-year follow-up, the mean central vaulting was reduced to 184+/-159 microm (range, 6-500 microm) and 138+/-218 microm (range, 0-820 microm) in eyes treated with V4 or early models, respectively. Eyes with total vaulting had a mean central vaulting of 407+/-202 microm (range, 180-730 microm), whereas those with midperipheral contact had a significantly lower central vaulting of 105+/-87 microm (range, 0-200 microm).

CONCLUSIONS

This study revealed consistent reduction of central vaulting over a 10-year period and provides further evidence that insufficient vaulting of the ICL is responsible for the development of anterior subcapsular cataract. A minimum central vaulting of 230 microm seems to be necessary to ensure total vaulting of the ICL. If an ICL is chosen for the correction of myopia, targeting for the greatest possible postoperative central vaulting is advised to achieve safe and complete vaulting for several years.

Vaulting of myopic and toric Implantable Collamer Lenses during accommodation measured with Visante optical coherence tomography

PURPOSE

To study changes in vaulting of myopic and toric Implantable Collamer Lenses (ICLs) version 4 during accommodation with Visante optical coherence tomography (OCT), and analyze the relationship between vaulting and anterior subcapsular opacification.

DESIGN

Cross-sectional study.

PARTICIPANTS

Seventy-seven eyes of 77 myopic patients were examined after implantation with an ICL (48 myopic, 29 toric). The median follow-up time was 63 months (range, 10-84).

METHODS

The distance between the posterior ICL surface and the anterior surface of the crystalline lens was measured in the nonaccommodative state and during accommodation with Visante OCT. The lenses were examined for opacification using slit-lamp microscopy.

MAIN OUTCOME MEASURES

The distance between the ICL and the anterior surface of the crystalline lens.

RESULTS

At baseline, the mean distance between the ICL and the crystalline lens was 0.31+/-0.19 mm and during accommodation 0.31+/-0.26 mm; the difference did not reach significance (P = 0.77). The distance at baseline was significantly (P = 0.01) less in older patients and significantly (P = 0.04) greater in patients with a toric ICL. Contact was observed at baseline or during accommodation in 12 eyes; there was a significantly lower incidence of contact in eyes implanted with a toric ICL (P = 0.03). Anterior subcapsular opacification developed in 10 eyes, in 5 of these the ICL touched the crystalline lens.

CONCLUSIONS

Anterior subcapsular opacification developed in 13.0% of eyes. We found no difference in vaulting of the ICL at baseline and during accommodation. There was contact between the ICL and the crystalline lens in 15.6% of the eyes. The association between anterior subcapsular opacification and contact was significant (P = 0.004).

White-to-white corneal diameter in the Tehran Eye Study

PURPOSE

To determine the mean corneal diameter and its determinants in the population of Tehran.

METHODS

From the Tehran Eye Study participants who were sampled through a stratified cluster approach, those in the first 4 municipality districts of Tehran were selected, and after applying the inclusion and exclusion criteria, 399 right eyes and 401 left eyes of 410 people aged 14 years and older were examined with the Orbscan II. The corneal diameter was defined as the horizontal limbus-to-limbus distance. Linear regression was used to detect separate and multiple correlations. The design effect of cluster sampling was also considered and adjusted for.

RESULTS

The studied participants were male in 38.80%, and their mean age was 40.68 +/- 16.80 years. The mean corneal diameter was 11.68 mm (95% confidence interval: 11.63-11.73). The 95% range (mean +/- 2 SDs) was 10.76-12.60 mm. The mean corneal diameter was 11.76 and 11.63 mm in males and females, respectively. The corneal diameter in the studied population had no significant correlation with age (P = 0.186) but showed an increase of 0.18 mm for each millimeter increase in the anterior chamber depth (P = 0.028).

CONCLUSION

Although the mean corneal diameter in the present population was not different from that reported in other studies, the data suggest that slightly different cutoff values for the definition of macrocornea (>12.60 mm) and microcornea (<10.76 mm) can be used with this population.

Posterior chamber phakic intraocular lens (ICL) for hyperopia: Ten-year follow-up

PURPOSE

To evaluate the long-term safety, efficacy, predictability, and stability of implantation of a Collamer implantable contact lens (ICL) (Staar) to correct hyperopic refractive errors.

SETTINGS

Ophthalmology Department, Santa Rita Hospital, Vercelli, Italy.

METHODS

Fifty-nine eyes of 34 patients with hyperopia had implantation of an ICL. Patients were examined preoperatively (baseline) and 1 day, 1 week, 1, 3, and 6 months, and 1, 2, 4, 6, 8, and 10 years postoperatively. Main outcome measures were subjective and objective refractions, uncorrected visual acuity, best corrected visual acuity (BCVA), variation in intraocular pressure (IOP), anterior chamber depth (ACD), variation in endothelial cells, adverse events, and patient satisfaction.

RESULTS

Nine patients had ICL implantation in 1 eye and 25 patients, in both eyes. Preoperatively, the spherical equivalent (SE) was between +2.75 diopters (D) and +11.75 D and astigmatism was between +0.50 D and +1.00 D. The mean SE of the manifest refraction was +0.07 +/- 0.54 D; refraction stabilized quickly and remained stable throughout the follow-up period. At 10 years, the safety index was 111 and the efficacy index, 96.8. Of the eyes, 86.5% had a change in SE refraction within +/-0.50 D; 1.6% lost 1 Snellen line of BCVA. The mean endothelial cell loss was 4.7%, which remained almost unchanged throughout the follow-up period. The mean variation in ACD was -14.9% and in IOP, +5.3%.

CONCLUSIONS

The results confirmed the long-term safety, efficacy, accuracy, and predictability of ICL implantation for hyperopia. The Collamer material was well tolerated in all eyes.

Two-year follow-up of the Artisan/Verisyse iris-supported phakic intraocular lens for the correction of high myopia

PURPOSE

To evaluate the implantation of Artisan/Verisyse phakic intraocular lenses (pIOLs) (Advanced Medical Optics) as an effective and safe method for the correction of high myopia.

SETTING

Department of Ophthalmology, John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA.

METHODS

This retrospective outcomes trial examined the implantation of Artisan/Verisyse pIOLs in 85 highly myopic eyes (mean spherical equivalent -12.2 diopters). Patients were followed for 2 years and examined postoperatively at 1,6,12, and 24 months. Data collected included best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), corneal endothelial cell density, and adverse events.

RESULTS

Six months postoperatively, 5 (7%) eyes lost 1 line of the BSCVA; no eye lost 2 or more lines. The UCVA was better than 20/40 in 83% of eyes and better than 20/25 in 32%. Endothelial cell density decreased by 3.3% and 6.5% over the 1-year and 2-year intervals, respectively. Glare and halos, the most common complications of surgery, were reported by 6% of patients at 1 month and by 3% at 2 years.

CONCLUSION

Implantation of the Verisyse/Artisan pIOL yielded accurate refractive results with acceptable safety in highly myopic eyes.

[Ultrasound biomicroscopy of posterior chamber phakic intraocular lenses: a comparative study between ICL and PRL models]

PURPOSE

To evaluate the anatomic relationships of the implantable contact lens (ICL) and the phakic refractive lens (PRL) posterior chamber phakic intraocular lenses (PCP IOL) using ultrasound biomicroscopy (UBM).

MATERIAL AND METHODS

Seventeen phakic myopic eyes corrected with ICL, and 14 phakic myopic eyes that had had PRL implantation, were examined retrospectively using UBM. The main parameters measured and compared were anterior chamber depth, central and peripheral distance between PCP IOL and the crystalline lens, and exact lens haptic position.

RESULTS

The mean distance between the PCP IOL and the central endothelium was 2398+/-203 microm and 2640+/-230 microm in the ICL and PRL groups, respectively. The central vault between the implant and the crystalline lens was greater in eyes with ICL (ICL, 402+/-194 microm; PRL, 256+/-187 microm, p<0.05). However, the incidence of lens contact on the peripheral level was higher in the ICL group (41%) than in the PRL group (29%), and the difference between the two implants in the peripheral crystalline lens-PCP IOL distance was significant (p<0.05). Both IOL haptics appeared to be correctly positioned in the sulcus in 13 (76%) eyes of the ICL group, and on the zonule in eight eyes (57%) of the PRL group.

CONCLUSIONS

PCP IOL implantation is a safe procedure for the correction of high myopia with regard to refractive results. UBM provides a unique tool to noninvasively evaluate the relations of these implants within the posterior chamber, and helps to analyze the mechanisms of crystalline lens and iris complications.

Toric Implantable Collamer Lens for moderate to high myopic astigmatism

PURPOSE

To assess the efficacy of the Toric Implantable Collamer Lens (ICL) to treat moderate to high myopic astigmatism.

DESIGN

Prospective nonrandomized clinical trial.

PARTICIPANTS

Two hundred ten eyes of 124 patients with between 2.38 and 19.5 diopters (D) of myopia (spherical equivalent [SE]) and 1 to 4 D of astigmatism participating in the United States Food and Drug Administration clinical trial of the Toric ICL.

INTERVENTION

Implantation of the Toric ICL.

MAIN OUTCOME MEASURES

Uncorrected visual acuity (UCVA), refraction, best spectacle-corrected visual acuity (BSCVA), adverse events, and postoperative complications.

RESULTS

At 12 months postoperatively, the proportion of eyes with 20/20 or better UCVA (83.1%) was identical to the proportion of eyes with preoperative 20/20 or better BSCVA (83.1%); 76.5% had postoperative UCVA better than or equal to preoperative BSCVA. The mean manifest refractive cylinder dropped from 1.93 D (+/-0.84) at baseline to 0.51 D (+/-0.48) postoperatively, a 73.6% decrease in astigmatism. Although only 21.0% of eyes had 1-D refractive cylinder preoperatively (none less), 91.4% of cases had < or =1 D of cylinder postoperatively. Furthermore, 65.6% had < or =0.5 D and 40.9% had < or =0.25 D of refractive cylinder postoperatively. Mean manifest refraction SE (MRSE) improved from -9.36 D (+/-2.66) preoperatively to 0.05 D (+/-0.46) postoperatively. A total of 76.9% of eyes were predicted accurately to within +/-0.5 D, 97.3% to within +/-1.0 D, and 100% to within +/-2.0 D of predicted MRSE. Postoperatively, 37.6% of eyes had a BSCVA of 20/12.5 or better, compared with a preoperative level of 4.8%. Furthermore, BSCVA of 20/20 or better occurred in 96.8% postoperatively, compared with 83.1% preoperatively. Mean improvement in BSCVA was 0.88 lines; there were 3 cases (1.6%) that lost > or =2 lines of BSCVA after 12 months postoperatively, whereas 18.9% of cases improved by > or =2 lines. A total of 76.4% of cases gained > or =1 lines of BSCVA, whereas only 7.5% of cases lost the equivalent amount. Three ICL removals were performed without significant loss of BSCVA, and 1 clinically significant lens opacity was observed.

CONCLUSION

The results support the efficacy and predictability of Toric ICL implantation to treat moderate to high myopic astigmatism. Important safety concerns were not identified.

Ultrasound Biomicroscopy for Determining Visian Implantable Contact Lens Length in Phakic IOL Implantation

PURPOSE

To assess the efficacy of the ultrasound biomicroscopic (UBM) method in estimating the sulcus-to-sulcus horizontal diameter for Visian Implantable Contact Lens (ICL, model V4) length determination to obtain optimal ICL vault.

METHODS

The results of postoperative ICL vaults in 30 eyes of 18 patients were retrospectively analyzed. In 17 eyes, ICL length was determined using the conventional method, and in 13 eyes, ICL length was determined using the UBM method. The UBM method was carried out by measuring the sulcus to limbus distance on each side by 50 MHz UBM and adding the white-to-white diameter by caliper or Orbscan. The ICL vaults were measured using the UBM method at 1 and 6 months postoperatively and the results were compared between the two groups. Ideal ICL vault was defined as vault between 250 and 750 microm. The relation between the ICL vault, footplate location, and ICL power was also investigated.

RESULTS

In the UBM method group, ICL vault was within the ideal range in all 13 (100%) eyes at 1 and 6 months postoperatively, whereas in the conventional method group, 10 (58.8%) eyes showed ideal vault at 1 month postoperatively (P = .01) and 9 (52.9%) eyes showed ideal vault at 6 months postoperatively (P < .01). The ideal ICL footplate location was achieved in the ciliary sulcus in 11 (84.6%) eyes of the UBM method group and 10 (64.7%) eyes of the conventional method group. However, the differences between the two groups were not statistically significant. The ICL vault was not significantly affected by the ICL power.

CONCLUSIONS

Implantable Contact Lens length determined by the UBM method achieved significantly more ideal ICL vault than that of the conventional white-to-white method. The UBM method is superior to the conventional method in terms of predicting the sulcus-to-sulcus horizontal diameter for ICL length determination.

Iris and trabecular meshwork pigment changes after posterior chamber phakic intraocular lens implantation

PURPOSE

To evaluate the changes in laser iridotomies, intraocular pressure (IOP), angle structures, and pupil diameter after implantable contact lens (ICL) (Version 4 Staar Surgical) implantation in myopic Asian eyes.

SETTING

Department of Ophthalmology, Chung-Ang University Yongsan Hospital, Seoul, Korea.

METHODS

The ICL was implanted in 81 eyes of 43 patients with spherical equivalent greater than -6.00 diopters. Gonioscopy examination was performed 1 day after laser iridotomy and 6 and 12 months after ICL implantation. The changes in laser iridotomy sites, IOP, and pupil diameter were also evaluated.

RESULTS

Ten eyes (12.3%) had occlusion or narrowing of the laser iridotomy sites. The angle width was more than 30 degrees in all cases preoperatively but narrowed to less than 20 degrees in 16 eyes (19.8%) 6 months postoperatively. The mean pigment, measured by the semiquantitative method (grade 0 to 4), was 2.03 in the inferior angle, 0.18 in the nasal angle, 0.12 in the temporal angle, and 0.00 in the superior angle 12 months postoperatively. The pigment in all quadrants increased temporally as a result of the laser iridotomy or iris rubbing by the ICL; however, the pigments absorbed gradually and decreased to values before laser iridotomy 12 months postoperatively. There was a temporary increase in IOP from the instillation of steroid eyedrops 1 week and 1 month postoperatively; IOP returned to the preoperative level and remained there 12 months postoperatively. There was a significant decrease in pupil diameter 1 and 3 months postoperatively; the diameter returned to the preoperative size at 6 and 12 months. Pigment dispersion syndrome and pigmentary glaucoma were not seen.

CONCLUSION

Implantation of the ICL narrowed the angle width but did not increase trabecular pigmentation compared with values after laser iridotomy, indicating ICL implantation is safe regardless of the pigmentary changes in the trabecular meshwork.

[GBR foldable anterior phakic intraocular lens with angular supports: a 3-year experience]

PURPOSE

The purpose of this study was to evaluate the efficiency, predictability, and safety of the GBR foldable anterior chamber implant with angular supports to correct high myopia after 3 years of follow-up.

MATERIAL

and methods: A GBR anterior chamber lens with angular supports was implanted in 44 eyes between November 2001 and February 2004. These eyes were highly myopic (preoperative mean of -10.65 +/- 2.62 diopters (D) (range, -6.25 to -16.50 D). Visual acuity, refraction, biomicroscopy, and quality of vision were estimated with a follow-up of 3 years. The potential complications required endothelial density, mobility of the pupil, intraocular pressure, and gonioscopy measurements.

RESULTS

No severe intra- or postoperative complications required an ablation of the lens. Increased intraocular pressure in three cases and decentration in one were the most serious side effects reported. Eighteen eyes (40.9%) presented pupil ovalization; 68.2% of the eyes reached the attempted correction +/-0.50 D. Implants seemed stable in their position and refractive results. Functional signs included night glare for eight patients (18.2%) and glare in the sun for 11 (25%). There was no significant decrease in cellular endothelial density mean during follow-up.

CONCLUSION

The GBR implant (Ioltech) is the pioneer of foldable anterior chamber implants, a concept in full expansion. Long-term satisfaction of the operated patients is encouraging. However, the medium-term anatomical modifications noted require monitoring and a search for the responsible mechanism.

Visual improvement in high myopic amblyopic adult eyes following phakic anterior chamber intraocular lens implantation

PURPOSE

To evaluate the efficacy and safety of angle-supported phakic anterior chamber intraocular lenses in amblyopic adult eyes with very high myopia.

METHODS

We evaluated 12 eyes in nine patients with very high myopic amblyopia who received angle-supported phakic intraocular lenses (Phakic 6H) and followed them for more than six months. Uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and complications were evaluated. A satisfaction score was rated by patients using a 5-point (1-5) numeric scale.

RESULTS

The mean age of patients was 37.3 +/- 9.4 years, ranging from 29 to 59 years old. The preoperative mean refraction (spherical equivalent, SE) was -20.10 +/- 5.41 diopters (D). The postoperative mean refraction (SE) was -1.75 +/- 0.76 D at six months. The postoperative BCVA improved an average 3.92 +/- 1.24 lines over preoperative values, and mean endothelial cell loss was 8.9% at six months. Development of cataracts, glaucoma, and pupil abnormalities were not demonstrated in any case during the study. The patients were all very satisfied, as the average satisfaction score was 4.3.

CONCLUSIONS

This study indicates that angle-supported phakic anterior chamber intraocular lens implantation may be an effective surgical alternative for the correction of amblyopic adult eyes with very high myopia. However, long-term evaluation is necessary to assess possible complications and long-term safety.

Age-related behavior of posterior chamber lenses in myopic phakic eyes during accommodation measured by anterior segment partial coherence interferometry

PURPOSE

To evaluate age-related position shifts of the crystalline lens and the implantable contact lens (ICL, Staar Surgical) by a new, commercially available, anterior segment partial coherence interferometer, the ACMaster (Carl Zeiss Meditec), during accommodation in myopic eyes.

SETTING

ALZ Augenklinik, Munich, Germany.

METHODS

Fifty-three eyes of 29 consecutive patients were measured after myopic ICL implantation before and during subjective accommodation to a stimulus of 3 diopters (D) by anterior segment partial coherence interferometry (PCI). Nine eyes were also measured with a 5.00 diopters (D) stimulus; 14 eyes were measured repeatedly at different visits. The mean patient age was 33 years +/- 9 (SD) (range 21 to 59 years). The preoperative mean sphere was -7.6 +/- 1.9 D (range -5.0 to -11.5 D) and the cylinder, -1.4 +/- 1.1 D (range 0 to -4.25 D).

RESULTS

Older patients had a tendency toward smaller vaults on desaccommodation between the ICL and the crystalline lens compared to younger individuals. In younger patients, there was a decrease of the vault on accommodation, whereas it increased in older persons (P = .005). During accommodation, the more the anterior lens surface shifted forward, the more the ICL bulged (P = .005). The change in vaulting was significantly larger at 5.00 D than at 3.00 D accommodation stimulus (P = .012).

CONCLUSIONS

The behavior of ICLs in relation to the crystalline lens during accommodation varied with age and could be shown by PCI. The position shift of the ICL depended on the initial vault at desaccommodation and the ability of the anterior lens surface to bulge forward. Even though the crystalline lens stiffened, and therefore accommodation deteriorated with age, there was still a movement of the ICL, pointing to the role of the ciliary muscle movement in accommodation.

Changes in the crystalline lens resulting from insertion of a phakic IOL (ICL) into the porcine eye

BACKGROUND

Insertion of a phakic IOL offers these advantages: the corneal optical zone is not dissected or resected; preservation of the crystalline lens results in preservation of the accommodation force; and since the phakic IOL is removable, any error or change in refraction can be countered by exchanging it. However, the cause of secondary cataracts has never been clarified or discussed to date.

METHODS

The following ICL lenses were inserted under general anaesthesia into 20 eyes of ten 3-month-old miniature pigs: a minus lens without holes into five eyes, a plus lens in two eyes, a minus lens with four holes around the lens haptics in three eyes, and a minus lens with a central hole in the optic in three eyes; and seven eyes were used as controls. The anterior segments were then photographed 1 week, 1 month and 3 months after surgery. At 3 months after surgery, Evans blue (EB) was infused into the vitreous under general anaesthesia, and after 30 min, the eyeball was enucleated, fixed and examined.

RESULTS

In the case of the ICL without holes, the anterior subcapsular opacities were observed in all the eyes, and the anterior surfaces of the crystalline lenses were not stained with EB. Use of the ICL with four holes around the lens haptics resulted in light staining of the anterior surface of the crystalline lens, but the anterior subcapsular opacities observed were mild. As for the ICL with a hole in the centre of the optic, the anterior surface of the crystalline lens was stained and no anterior subcapsular opacities were observed.

CONCLUSION

The results suggested that the insertion of an ICL brings about a change in the dynamics of the intraocular aqueous humour, reducing its circulation to the anterior surface of the crystalline lens. This is considered to cause a metabolic disturbance of the crystalline lens, resulting in anterior subcapsular opacification.

Results of cataract extraction after implantable contact lens removal

PURPOSE

To evaluate the visual results following insertion of implantable contact lenses (ICLs) in ametropic eyes and the development of subcapsular opacification with visual loss and to examine the anterior capsule, including the subcapsular tissue alteration, by light microscopy.

SETTING

Department of Ophthalmology, Schlosspark-Klinik, affiliated hospital of the Charité Berlin, Humbold University, Berlin, Germany.

METHODS

A prospective noncomparative interventional case series of anterior subcapsular cataracts in 9 of 127 (7.1%) patient eyes receiving ICLs to correct myopia and hyperopia was studied. The cataracts were phacoemulsified due to visual loss, and an intraocular lens (IOL) was implanted in the bag. After capsulorhexis, the anterior capsule was withdrawn for light microscopy examination. Visual acuity in each eye was measured before and after ICL implantation and before and after cataract extraction. The age range of cataract patients was 39 to 53 years.

RESULTS

Implantable contact lens removal and phacoemulsification with IOL implantation for emmetropia resulted in an increased visual acuity compared to initial vision. Four of 28 hyperopic eyes (14.3%) developed subcapsular central opacification after ICL implantation, whereas 5 of 99 myopic patients (5.1%) developed opacifications.

CONCLUSIONS

Patients should be informed prior to ICL implantation, there is a possibility of secondary subcapsular cataract formation and vision reduction. Although the posterior chamber inlay as well as the cataract can be removed and better acuity can be restored, a possible complication due to the ICL implantation cannot be avoided and the accommodation in young patients lost.

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.

Pupillary capture of implantable contact lens after blunt trauma

A 33-year-old woman visited our clinic with blurry vision and periorbital swelling after experiencing blunt trauma to left eye. Ten months earlier, she had implantable contact lens (ICL) implantation in the left eye. Biomicroscopic examination showed that that 1 footplate of the ICL was entrapped in the pupillary aperture at the 7 o'clock position and the ICL was placed vertically. The patient had limited ocular movement in lateral gaze, and the computed tomography showed a medial orbital wall fracture. Pupillary capture of the ICL was surgically corrected with an iris manipulator under topical anesthesia. After the ICL was repositioned, the patient's uncorrected visual acuity was restored to 20/32, as before the injury. Pupillary capture of the ICL may occur after blunt ocular trauma.

Traumatic cataract and other adverse events with the implantable contact lens

PURPOSE

To evaluate the surgical outcome and adverse events associated with implantation of the implantable contact lens (ICL) for the correction of high myopia or high hyperopia.

SETTING

Helsinki University Eye Hospital, Helsinki, Finland.

METHODS

In this nonrandomized prospective clinical trial, the ICL V4 was implanted in 26 eyes of 13 patients with normal enrollment criteria (younger than 45 years, a clinically clear crystalline lens) (Group 1) and the V2, V3, or V4 were implanted in 38 eyes of 22 patients with heterogeneous criteria (older than 45 years or opacities in the crystalline lens) (Group 2). The main outcome measures were lens opacity classification system (LOCS II) assessment and transparency analysis of the lens.

RESULTS

In Group 1, microdensitometric assessment showed no decrease in crystalline lens transparency and no statistically significant increase in crystalline lens density at any follow-up examination (P>.05). The incidence of anterior subcapsular (AS) opacities was 7.7%, and no eye developed clinically significant cataract during the mean follow-up of 13.2 months +/- 12.3 (SD). No myopic eye lost a line of best corrected visual acuity (BCVA); 50.0% of hyperopic eyes lost 1 line of BCVA. Sixty-eight percent of myopic eyes and 75.0% of hyperopic eyes were within +/-1.0 diopter of the predicted refraction. In Group 2, the incidence of AS opacities was 47.4% and 10 eyes (26.3%) developed clinically significant cataract during the mean follow-up of 30.9 +/- 18.0 months. The visual and refractive results were similar to those in Group 1 at 1 month, but due to progressive AS opacities in the crystalline lens, 23.4% of eyes lost BCVA lines during the follow-up. Intraoperative complications were few and insignificant.

CONCLUSIONS

Implantation of the ICL for correction of high myopia or high hyperopia appears to be a safe procedure with good visual and refractive results immediately. There was no decrease in the transparency or increase in the density of the crystalline lens with the latest generation of the ICL device in the normal group, indicating enhanced safety. Progressive lens opacification in the heterogeneous group shows there are risk factors for cataract formation; ie, type V3 ICL, preexisting lens opacities, and older patient age. Anterior subcapsular opacities are most likely the result of trauma.

White-to-white corneal diameter: normal values in healthy humans obtained with the Orbscan II topography system

PURPOSE

The corneal horizontal diameter (white-to-white) is abnormal in diseases like microcornea, relative anterior microphthalmos, and corneal dystrophies. Because normal values are described imprecisely in the literature, the purpose of this study was to reevaluate the horizontal corneal diameter as a scientific parameter.

METHODS

The horizontal corneal diameter was measured with the Orbscan II system in 370 right eyes and 373 left eyes of 390 healthy white subjects aged 10-80 years. There were 148 female subjects and 242 male subjects. Each measurement was repeated twice. Differences in gender, between right and left eyes, and age-related alterations were analyzed statistically.

RESULTS

The average corneal diameter was 11.71 +/- 0.42 mm. The average corneal diameter was 11.77 +/- 0.37 mm in males compared with 11.64 +/- 0.47 mm in females. The resulting normal ranges were 11.04 to 12.50 for males and 10.70 to 12.58 mm for females. Differences in gender were not significant in the t test for independent samples (P = 0.071). There were no statistically significant differences between right and left eyes in the t test for dependent samples (P = 0.16). Corneal diameters decreased slightly with age.

CONCLUSIONS

With the obtained normal values, more precise determination of microcornea and macrocornea will be possible in the future. The horizontal corneal diameter was not significantly greater in males than in females. Further studies are needed to show the reasons for the age-related decrease in measurements.