Long-term results of implantation of phakic posterior chamber intraocular lenses

Three-year outcomes of a novel toric intraocular lens implantation for moderate-high myopic astigmatism in phakic eyes

PURPOSE

To investigate the three-year visual, refractive outcomes and adverse events of the Eyecryl toric phakic IOL (pIOL) for moderate-to-high myopic astigmatism.

METHODS

This retrospective study included eligible patients who underwent refractive surgery in one or both eyes with Eyecryl toric pIOL for myopic astigmatism. The efficacy, safety, predictability, rotational stability, vector analysis, and adverse events were evaluated in patients with spherical refraction from - 4.50 to -17.00 diopters (D) and cylindrical refraction from - 0.75 to -5.50 D.

RESULTS

Fifty-two eyes of 28 patients were included in the study. The mean efficacy and safety index were 1.12 ± 0.35 and 1.38 ± 0.42, respectively. The mean manifest refraction spherical equivalent was - 10.06 ± 2.69 D and - 0.64 ± 0.61 D preoperatively and postoperatively at 36 months, respectively. The mean manifest astigmatism was - 2.06 ± 1.16 D and - 0.44 ± 0.48 D preoperatively and 36 months postoperative, respectively. During the final examination, 70% of the eyes showed an increase in CDVA of one or more lines compared to their preoperative state. There was a cumulative endothelial cell loss of 3.1% at 36 months postoperatively. One eye developed visually significant anterior subcapsular opacity, whereas another eye experienced pIOL opacification.

CONCLUSION

The Eyecryl toric pIOL demonstrated satisfactory visual acuity and refractive outcomes, as assessed by efficacy, safety and stability over a three-year period.

Causes and outcomes of implantable collamer lens explantation in patients with corneal endothelial cell loss

PURPOSE

To investigate the correlated factors of corneal endothelial cell density (ECD) loss and ECD change in implantable collamer lens (ICL) explantation patients.

SETTING

Seoul St. Mary's Hospital, Seoul, South Korea.

DESIGN

Retrospective analysis.

METHODS

The study cohort consisted of 93 eyes from 50 patients who underwent ICL explantation. Correlation analysis was performed to assess the ocular parameters associated with ECD loss, while percentage of ECD change (ΔECD%) was monitored up to 6 months postoperatively. Receiver operating characteristic (ROC) curve was used to set cutoff values of ocular parameters to prevent ECD loss after explantation.

RESULTS

In multiple regression analysis, high vaulting, high vaulting/anterior chamber depth (ACD), low anterior chamber angle (ACA), and high iris pigmentations are the significant factors of ECD loss. At postoperative 6 months, 14 eyes (15.1%) had decrease (10.5% loss), 47 eyes (51.0%) were stationary, and 32 eyes (34.4%) had increase (12.7% gain) of ECD. The ROC curve analysis showed that vaulting had the highest area under the curve (AUC = 0.822), followed by vaulting/ACD (AUC = 0.821), ECD (AUC = 0.753), and ACA (AUC = 0.723) (all P < .01). Preoperative ECD showed a sensitivity of 77.6% and specificity of 86.7% in preventing ECD loss after explantation, with a cutoff value of 1722 cells/mm 2 , as determined by ROC curve analysis.

CONCLUSIONS

Our study demonstrated that high vaulting is a significant factor in ECD loss among ICL-inserted patients. To prevent continuous ECD loss in ICL patients, close monitoring of ECD and making appropriate decisions regarding explantation may be necessary.

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.

Seven-Year clinical outcomes after implantation of Eyecryl posterior chamber phakic intraocular lenses for high myopia

PURPOSE

To evaluate the long-term clinical outcomes, safety and efficacy of Eyecryl posterior-chamber phakic intraocular lens implantation (pIOL) implantation in patients with high myopia.

METHODS

Patients with myopia between -6.00 and -20.00 dioptres and with endothelial cell density (ECD) was ≥2300 cells/mm2 were included. Preoperative and postoperative first, fourth, and seventh years of refraction, uncorrected/corrected distance visual acuity (UDVA/CDVA), ECD, central vault were detected.

RESULTS

Thirty-six eyes were analyzed. The mean UDVA and CDVA in postoperative seventh years were 0.25 ± 0.31 and 0.13 ± 0.24 logMAR, respectively. The safety and efficacy indices were 1.55 ± 0.54 and 1.24 ± 0.53, respectively. The mean cumulative ECD loss was 6.96% (p < 0.001). The central vault at the 1st and the 7th year were 0.52 ± 0.14 and 0.49 ± 0.14 mm, respectively (p = 0.25).

CONCLUSIONS

These findings supported the long-term stability, efficacy, safety of the Eyecryl pIOL for high myopia. Eyecryl posterior chamber pIOL is one of the effective refractive options in correcting high myopia.

Three-Dimensional Quantitative Description of the Implantable Collamer Lens in the Ocular Anterior Segment of Patients With Myopia

PURPOSE

To describe the 3-dimensional (3D) location of the implantable collamer lens (ICL) quantitatively in the posterior ocular chamber of patients with myopia.

DESIGN

Cross-sectional study.

METHODS

To obtain visualization models before and after mydriasis, an automatic 3D imaging method based on swept-source optical coherence tomography was created. Parameters like the ICL lens volume (ILV), the tilt of the ICL and crystalline lens, the vault distribution index, and topographic maps were evaluated to describe the ICL location. Using a paired sample t test and the Wilcoxon signed rank test, the difference between nonmydriasis and postmydriasis conditions was compared.

RESULTS

The study investigated 32 eyes from 20 patients. The 3D central vault did not differ significantly before (P = .994) or after mydriasis (P = .549) compared with the 2D central vault. After mydriasis, the 5-mm ILV decreased by 0.85 mm2 (P = .016), and the vault distribution index increased significantly (P = .001). The ICL and the crystalline lens exhibited tilt (nonmydriasis: ICL total tilt 3.78 ± 1.85 degrees, lens total tilt 4.03 ± 1.53 degrees; postmydriasis: ICL total tilt 3.84 ± 1.56 degrees, lens total tilt 4.09 ± 1.64 degrees). The phenomenon of asynchronous tilt of the ICL and lens was found in 5 eyes, leading to the spatially asymmetric distribution of the ICL-lens distance.

CONCLUSION

The 3D imaging technique provided exhaustive and reliable data for the anterior segment. The visualization models offered multiple perspectives on the ICL in the posterior chamber. Before and after mydriasis, the intraocular ICL position was described by the 3D parameters.

Diagnostic Techniques to Increase the Safety of Phakic Intraocular Lenses

Preoperative and postoperative diagnostics play an important role in ensuring the safety of patients with phakic intraocular lenses (pIOLs). The risk of endothelial cell loss can be addressed by regularly measuring the endothelial cell density using specular microscopy and considering the endothelial cell loss rate and the endothelial reserve in accordance with the patient's age when deciding whether to explant a pIOL. The anterior chamber morphometrics, including the anterior chamber depth and the distance between the pIOL and the endothelium, measured using Scheimpflug tomography and anterior segment optical coherence tomography (AS-OCT), can help to assess the risk of the endothelial cell loss. In patients undergoing posterior chamber pIOL implantation, accurate prediction of the vault and its postoperative measurements using AS-OCT or Scheimpflug tomography are important when assessing the risk of anterior subcapsular cataract and secondary glaucoma. Novel approaches based on ultrasound biomicroscopy and AS-OCT have been proposed to increase the vault prediction accuracy and to identify eyes in which prediction errors are more likely. Careful patient selection and regular postoperative follow-up visits can reduce the complication risk and enable early intervention if a complication occurs.

Long-term results of a new posterior chamber phakic intraocular lens in patients with high myopia: 5-year results

PURPOSE

To evaluate the long-term refractive outcomes of Eyecryl posterior chamber spherical phakic intraocular lens (pIOL) implantation in high myopia and endothelial cell density (ECD) change.

SETTING

Beyoglu Eye Training and Research Hospital, Istanbul, Turkey.

DESIGN

Retrospective.

METHODS

Eyes that were not suitable for corneal refractive surgery, had high myopia between -6.00 diopters (D) and -20.00 D, had Eyecryl posterior chamber spherical pIOL implantation, and had at least 5 years of follow-up were included. Preoperative ECD was ≥2300 cells/mm 2 and cylindrical value was ≤2.0 D in all cases. Preoperative and postoperative first, third, and fifth years of refraction, uncorrected and corrected distance visual acuity (UDVA/CDVA), and ECD were recorded.

RESULTS

36 eyes of 18 patients were examined. The mean UDVA and CDVA in postoperative fifth years were 0.24 ± 0.19 logMAR and 0.12 ± 0.18 logMAR, respectively. The safety and efficacy indices were 1.52 ± 0.54 and 1.14 ± 0.38, respectively. At 5 years, the spherical equivalent was ±0.50 D in 75% of eyes and ±1.00 D in 92% of eyes. After 5 years, the mean cumulative ECD loss was 6.91% ( P = .07). The annual ECD loss was 1.57% in the first year, 0.26% between 1 year and 3 years, and 2.38% between 3 years and 5 years. Asymptomatic anterior capsule opacity developed in 1 eye 4 years after surgery. Rhegmatogenous retinal detachment developed in 1, and myopic choroidal neovascular membrane occurred in 1 eye.

CONCLUSIONS

Eyecryl posterior chamber spherical pIOL implantation is one of the effective and safe refractive surgical methods in correcting high myopia with predictable and stable refractive results over a 5-year period. Longer-term studies are needed for complications such as decreased ECD, retinal complications, and lens opacity.

Pure ICL Implantation: A Novel Ophthalmic Viscosurgical Device-Free Method

PURPOSE

To assess the clinical efficiency of a novel ophthalmic viscosurgical device-free (OVD-free) method for intraocular collamer lens (EVO-ICL) implantation in myopic eyes.

METHODS

In this study, 40 patients underwent ICL implantation for both eyes: one eye underwent traditional ICL implantation, and the other eye underwent OVD-free (pure) ICL implantation. Preoperative and postoperative UDVA, BCVA, equivalent spherical degree (SE), IOP, visual quality index, subjective visual quality scale, corneal endothelial cell density (ECD), operation time, and complications were compared between and within the traditional and pure ICL implantation groups.

RESULTS

Increased IOP >22 mmHg 2 h after surgery was noted in 8 eyes (20%) in the traditional group, but not in the pure group (0%, P < 0.001). Increased IOP relative to baseline was significantly higher at 2 h after surgery for the traditional group compared with the pure group (P < 0.001). UDVA, BCVA, and SE were significantly improved in the pure group compared with those in the traditional group 1 day (P < 0.001, P=0.003) after implantation, but not 1 week or 3 months after. Modulation transfer function cut-off frequency (MTF cut-off), Strehl ratio (SR), and OV20% were significantly better in the pure group than in the traditional group 1 day after implantation (P=0.013, P=0.009, and P=0.004). No significant difference in ECD changes within or between groups was observed (P > 0.05). The operation time for the pure group (2.897 ± 0.346 min) was significantly shorter than that for the traditional group (4.444 ± 0.656 min; P < 0.001). No complications were reported for either group during the observation period, except early IOP elevation in the traditional group.

CONCLUSIONS

The pure ICL implantation method was associated with faster visual acuity recovery, shorter operation time, and more stable intraocular pressure. Pure ICL represents a safe and convenient method for ICL implantation compared with the traditional method, completely eliminating OVD-related complications without causing additional complications.

Long-term Clinical Outcomes of Implantable Collamer Lens

Purpose: To evaluate the long-term clinical outcomes of implantable collamer lens (ICL) implantation in myopic patients.Methods: This retrospective study included 129 eyes of 68 patients who underwent ICL implantation for correction of myopia with a 10-year follow-up.Results: Ten years after ICL implantation, the mean uncorrected and corrected distance visual acuities (LogMAR) were 0.03 ± 0.13 and -0.07 ± 0.06, respectively. Ten years postoperatively, 52.7% and 84.5% of the eyes were within ± 0.5 and ± 1.0 diopters, respectively. The mean efficacy and safety indices were 0.91 ± 0.22 and 1.07 ± 0.19, respectively. There was no significant difference between mean preoperative (13.52 ± 2.88 mmHg) and postoperative (13.59 ± 3.55 mmHg) intraocular pressures. The endothelial cell density decreased from before surgery to 10 years after surgery (3,074 ± 365 cells/mm2, 2,812 ± 406 cells/mm2, respectively; mean decrease: 8.5 ± 10.8%; p = 0.011). Eight eyes (6.2%) developed cataract during follow-up, which was symptomatic in three eyes (2.3%) and treated with ICL explantation and phacoemulsification. Rhegmatogenous retinal detachment occurred in one eye (0.8%) and was treated with vitrectomy.Conclusions: ICL implantation for the correction of myopia had good efficacy and safety outcomes during long-term follow-up of 10 years. However, patients should be closely monitored for complications such as cataract formation, endothelial cell loss, and retinal detachment.

Changes in anterior lens density after Implantable Collamer Lens V4c implantation: a 4-year prospective observational study

PURPOSE

To investigate the changes in anterior lens density with a Pentacam after Implantable Collamer Lens (ICL) V4c implantation in patients with myopia.

METHODS

This prospective case series examined 62 eyes of 32 patients (mean age, 28.5 ± 5.73 years) with myopia or myopic astigmatism after ICL V4c implantation. Uncorrected distance vision acuity, corrected distance vision acuity (CDVA), manifest refraction, intraocular pressure, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), endothelial cell density and Pentacam images of lens density were obtained pre- and postoperatively. The vault was obtained during the follow-ups.

RESULTS

Patients were followed up for an average of 51 ± 2.7 months (range, 48-57 months). All surgeries were uneventful, without any complication. The efficacy and safety indices at the last follow-up were 1.03 ± 0.2 and 1.22 ± 0.22, respectively. No eye had decreased CDVA, and 66% eyes gained ≥1 line. Furthermore, refractive error in 90% eyes was within ±0.50 D and that of 100% was within ±1.0 D of the attempted refraction. Anterior average lens density (a-ALD) in the 0.5-, 1.0- and 1.5-mm depth zones increased by 10.41 ± 11.51%, 17.1 ± 11.09% and 16.76 ± 10.4%, respectively, compared to preoperative values (all p < 0.05). The change in a-ALD between two different age groups was not significant. Moreover, there were no significant correlations between the change in a-ALD and age, preoperative spherical equivalent, ACD, ACA, ACV or vault.

CONCLUSIONS

Implantable Collamer Lens (ICL) V4c implantation demonstrates safety and efficacy for myopia correction. Although a-ALD increased slightly at 4 years postoperatively, no cataract developed during the follow-up. Further studies should investigate the reason for the postoperative increase in a-ALD.

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

PURPOSE

To investigate refractive and visual outcomes as well as rotational stability following implantation of Eyecryl phakic toric intraocular lens (pIOL) for moderate-to-high myopic astigmatism.

METHODS

The efficacy, safety, predictability, stability, and adverse events of Eyecryl toric pIOL were evaluated in patients with spherical refraction from - 4.50 to - 18.50 diopters (D) and cylindrical refraction from - 0.50 to - 5.50 D.

RESULTS

This study included 60 eyes of 31 patients. The mean manifest refraction spherical equivalent (MRSE) dropped from - 10.45 ± 2.74 D preoperatively to - 0.34 ± 0.51 D and - 0.40 ± 0.56 D at 6 and 12 months postoperatively, respectively. There was an 81% decrease in astigmatism after surgery. The safety and efficacy of indices were 1.36 ± 0.43 and 1.20 ± 0 .32. At the final follow-up, the rate of eyes within ± 1.00 D and ± 0.50 D of the desired MRSE were 85% and 68.33%, respectively. Vision-threatening complications were not observed during the follow-up.

CONCLUSIONS

The implantation of pIOL was effective, safe, and predictable in patients with moderate-to-high myopic astigmatism during 1-year follow-up.

Myopia

Myopia, also known as short-sightedness or near-sightedness, is a very common condition that typically starts in childhood. Severe forms of myopia (pathologic myopia) are associated with a risk of other associated ophthalmic problems. This disorder affects all populations and is reaching epidemic proportions in East Asia, although there are differences in prevalence between countries. Myopia is caused by both environmental and genetic risk factors. A range of myopia management and control strategies are available that can treat this condition, but it is clear that understanding the factors involved in delaying myopia onset and slowing its progression will be key to reducing the rapid rise in its global prevalence. To achieve this goal, improved data collection using wearable technology, in combination with collection and assessment of data on demographic, genetic and environmental risk factors and with artificial intelligence are needed. Improved public health strategies focusing on early detection or prevention combined with additional effective therapeutic interventions to limit myopia progression are also needed.

Posterior-Chamber Phakic Intraocular Lens Implantation in Patients over 40 Years of Age

Purpose

To assess the efficacy, safety, and predictability of the Visian Implantable Collamer Lens (ICL) model having a central port in patients over 40 years of age.

Methods

This study included 33 eyes from 21 patients who underwent V4c ICL implantation for the correction of myopia and myopic astigmatism. We assessed uncorrected (UDVA) and corrected (CDVA) distance visual acuity, refraction, intraocular pressure (IOP), endothelial cell density (ECD), vault, and adverse events occurring over a 1-year period.

Results

Mean age of the patients at the time of implantation was 43.52 ± 4.49 years (range: 40 to 56 years). Efficacy and safety indexes were 1 and 1.09, respectively. Surgical outcomes for CDVA were as follows: no eye lost any lines, 19 eyes (57.58%) showed no CDVA changes, 7 eyes (21.21%) gained 1 line, 4 eyes (12.12%) gained 2 lines, and 3 eyes (9.09%) gained ≥3 lines. Mean postoperative spherical equivalent (SE) was −0.09 ± 0.47 D. A total of 29 eyes (87.8%) were within ±0.50 D and 31 eyes (93.9%) were within ±1.00 D of the desired SE. At 1-year, mean IOP was 15.27 ± 3.03 mmHg (range: 9 to 20 mmHg, p=0.12 pre vs. post) and mean ECD was 2516 ± 234 cells/mm² (p=0.29 pre vs. post). Mean postoperative vault was 320 ± 136 μm, with 201–300 μm being the most prevalent vault range for 9 eyes (31.03%). None of the eyes showed a vault >701 μm. There were neither intraoperative nor postoperative complications; in fact, all ICL implantation procedures were uneventful.

Conclusions

Our study's findings support the use of this lens in patients over 40 years of age. A long follow-up period is advisable to monitor ICL position relative to the crystalline lens.

A novel ophthalmic viscosurgical device-free phakic intraocular lens implantation makes myopic surgery safer

Purpose

To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free (OVD-free) method for posterior chamber phakic intraocular lens (PIOL) implantation in myopic eyes.

Methods

In this retrospective cohort study, the medical records of myopic eyes that underwent PIOL (Implantable Collamer Lens, ICL) implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed. A total of 49 eyes with complete data that met follow up requirements (2 h, 1 day, 1 week, 3 months postoperatively) were recruited. Based on the surgical techniques used, the eyes were divided into the OVD-free method group and the standard method group. The clinical data, including intraocular pressure (IOP), corrected distance visual acuity (CDVA) and spherical equivalent (SE), at each follow-up were collected for comparison. Endothelial cell loss and complications were also investigated.

Results

Twenty-one eyes received the standard method, and 28 eyes received the OVD-free method. A rise in IOP > 22 mmHg at 2 h was noted in 14 eyes (66.7%) in the standard group and none (0%) in the OVD-free group (p < 0.001). The rise in IOP from baseline was significantly higher at 2 h in the standard group (10.5 ± 5.2 mmHg vs. 2.2 ± 3.3 mmHg, difference: 8.3, 95% CI 5.8 to 10.8; p < 0.001). There was a significant difference in the time course of LogMAR CDVA changes between the two groups (p = 0.047). The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day (− 0.076, 95% CI − 0.134 to − 0.018; p = 0.012), 1 week (− 0.071, 95% CI − 0.135 to − 0.007; p = 0.03), but not at 3 months (− 0.046, 95% CI − 0.107 to 0.015; p = 0.134). There was no significant difference in the time course of SE changes between the two groups (p = 0.471; p = 0.705). In the OVD-free group, mean endothelial cell loss was 4.6% at 3 months (2522 ± 281 vs. 2407 ± 226 cells/mm², difference: -115, 95% CI − 295 to 65; p = 0.187). No complications were reported in both groups except for the early IOP elevation in the standard group during the observation period.

Conclusions

The OVD-free method is safe and efficient for ICL implantation. It can be a safer method of ICL implantation compared to the standard method in that it completely eliminates ophthalmic viscoelastic devices-related complications without causing additional complications.

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.

Changes in Endothelial Cell Count Up to Three Years After Implantation of Toric Implantable Collamer Lenses

PURPOSE

To determine the temporal effect of toric implantable collamer lens (TICL) implantation and location on corneal endothelial cell density (ECD) over a period of 36 months after surgery.

METHODS

ECD [number of cells per square millimeter estimated using the Specular Microscope SP-1P (Topcon Europe Medical B.V., Netherlands)] data were collected from cases deemed suitable for the TICL (VTICMO, VTICM5; STAAR Surgical, Nidau, Switzerland). The preoperative refractive error (sphere and cylinder) ranged from -1.00 to -22.25 diopter sphere and from -0.50 to -5.50 diopter cylinder. ECD was evaluated at preoperative and all postoperative sessions.

RESULTS

Key findings were as follows: the mean ECD (±SD, 95% confidence interval) was 2720 cells/mm (±272, 2620-2820 cells/mm) preoperatively, which was reduced to 2372 cells/mm (±325, 2250-2490 cells/mm) at 36 months postoperatively (P < 0.001). Linear regression revealed the following significant correlations between the (1) log of the change in ECD (y1) and log of preoperative ECD (x1) at 2 years postoperatively, y1 = 2.513x1-6.2816 (n = 62, r= 0.3503, P = 0.005); (2) mean ECD (y2) and log time (in months, x2), y2= 2543.7-36.997x2-38.99x2 (r=-0.9654, n = 7, P = 0.0004); and (3) mean axial distance between the front surface of the crystalline lens and the TICL back surface (y3) and time postoperatively (in months, x3), y3 = 0.1035x3-5.2808x3 +473.18 (r = 0.8512, n = 7, P = 0.015).

CONCLUSIONS

Expected ECD loss after TICL implantation by 2 years postoperatively is predictable. On average, over 3 years after implantation, there is (1) an initial rapid decline in ECD, followed by a gradual fall in the rate of cell loss, and (2) a gradual fall in the distance between the TICL and the crystalline lens by 2 years postoperatively, followed by a reversal by the third year.

Implantable collamer lens with central hole: 3-year follow-up

Purpose

To evaluate the long-term predictability, stability, safety, and efficacy of the V4c Visian implantable collamer lens (ICL) with central hole to correct myopia.

Patients and methods

One hundred and eighty-four eyes of 92 patients were evaluated during 3 years after implantation of the V4c ICL. The refraction, uncorrected distance visual acuity, best-corrected distance visual acuity, IOP, endothelial cell count, vault, and adverse effects were evaluated every 12 months during the whole follow-up.

Results

The mean spherical equivalent dropped from -8.30±2.98 D preoperatively to −0.37±0.47 D at 36 months post-surgery, with 91.8% eyes being within ±1.00 D of emmetropia. With respect to the astigmatic components J0 and J45, 98.4% and 99.5% of eyes, respectively, were within ±0.50 D of the desired refraction. At 36 months, 78.8% of eyes had no change in the Snellen lines of best-corrected distance visual acuity, while 8.7% gained one line and 6.5% gained two or more lines; mean safety and efficacy indexes were 1.03 and 0.90, respectively. Mean endothelial cell count was 2,742±340 cells/mm² before and 2,663±366 cells/mm² at 36 months post-surgery. Mean IOP reduced from 13.7±1.9 mmHg preoperatively to 12.8±1.7 mmHg at 36 months post-surgery. Mean vault varied from 409±196 µm at 12 months to 349±165 µm at 36 months.

Conclusion

The visual and refractive outcomes were very good and highly stable throughout the follow-up period, indicating that this ICL model may be predictable, stable, safe, and effective to correct myopia in the long term.

Intentional Undercorrection by Implantation of Posterior Chamber Phakic Intraocular Lens With A Central Hole (Hole ICL) For Early Presbyopia

Purpose

To assess visual performance at near to far distances in early presbyopic patients with undercorrection by implantation of an ICL with a central hole (hole ICL).

Methods

This prospective study evaluated forty-two eyes of 21 early presbyopic patients (age, 40 to 53 years) with spherical equivalents of -7.37 ± 3.18 D [mean ± standard deviation] who underwent hole ICL implantation and whose targeted refraction was set at slight myopia (-0.61 ± 0.28 D) for both eyes. We assessed the safety, efficacy at near to far distances, predictability, and adverse events of the surgery, during the 6-month observation period.

Results

Corrected distance visual acuity did not improve significantly, from -0.17 ± 0.07 preoperatively to -0.19 ± 0.08 logMAR postoperatively (p=0.066, Wilcoxon signed-rank test). Uncorrected distance visual acuity was significantly improved from 1.30 ± 0.24 preoperatively to -0.03 ± 0.20 logMAR postoperatively (p<0.001). The mean binocular visual acuity was 0.02 logMAR or better at all distances (5.0, 3.0, 2.0, 1.0, 0.7, 0.5, and 0.3 m). All eyes were within ± 0.5 D of the targeted correction. Neither cataract formation, significant intraocular pressure rise, nor other vision-threatening complications occurred in any case during the 6-month observation period.

Conclusions

Our pilot study showed that intentional undercorrection by hole ICL implantation for early presbyopia was safe with predictable refractive results and provided good binocular vision at near to far distances, without developing cataract, suggesting its viability as a surgical presbyopic treatment for such patients.

Correction of presbyopia: An integrated update for the practical surgeon

Presbyopia results from loss or insufficiency of the eye's accommodative ability, and clinically manifests as the inability to focus near objects on the retina. It is one of the most common causes of visual impairment worldwide especially in adults of productive or working age. Various means of compensating for the loss of accommodative ability have been devised from optical tools such as spectacles and contact lenses, to topical medications and to surgical procedures. A comprehensive search on journal articles about topical and surgical correction of presbyopia was undertaken. The various techniques for presbyopia correction, as enumerated in these articles, are discussed in this paper with the addition of our personal experience and perspective on the future of these techniques.

Buffering zone of implantable Collamer lens sizing in V4c

Background

The purpose of this study was to identify factors related to the unexpected vault in V4c implantable collamer lens (ICL; STAAR Surgical) implantation.

Methods

V4c ICLs were implanted in 43 eyes of 43 patients for the correction of myopia. The implanted V4c ICL sizes were determined individually with our previous V4 ICL sizing nomogram based on the sulcus-to-sulcus diameter (STS), and the V4 ICL sizes were then converted to V4c ICL sizes with a size-converting table. We defined the “normal-sizing group” as having a pre-converted ICL size larger than the STS, and the “under-sizing group” as having a pre-converted ICL size smaller than the STS. Refractive outcomes, safety and parameters related to postoperative vault were compared between the two groups.

Results

The value of “actual ICL size – STS” differed significantly between the normal-sizing and under-sizing groups (p < 0.001), but postoperative vault did not differ significantly (p = 0.442). The demographics, implanted ICL characteristics, effectiveness indexes, safety indexes, and parameters related to postoperative vault did not differ significantly between the two groups (p > 0.05). Two patients in the normal-sizing group exhibited over-vaulting; these patients had shallow anterior chambers and were implanted with high-dioptric-power ICLs.

Conclusions

The achievement of acceptable vault in both normal-sizing and under-sizing groups indicates the existence of a buffering zone in V4c ICL sizing. The smaller size of V4c ICLs should be considered in patients susceptible to over-vaulting, such as those with shallow anterior chambers and high-dioptric-power ICLs.

Monovision by Implantation of Posterior Chamber Phakic Intraocular Lens with a Central Hole (Hole ICL) for Early Presbyopia

This study was aimed to evaluate visual performance at near to far distances in early presbyopic patients undergoing monovision by implantation of an ICL with a central hole (hole ICL). This pilot study comprised thirty-four eyes of 17 early presbyopic patients (age, 40 to 53 years) who underwent hole ICL implantation, and whose targeted refraction was set at emmetropia for the dominant eye, and at slight myopia (-0.5 to -1.0 diopters (D)) for the non-dominant eye. Corrected distance visual acuity was significantly improved, from -0.11 ± 0.07 preoperatively to -0.19 ± 0.09 logMAR postoperatively (p < 0.001, Wilcoxon signed-rank test). Uncorrected distance visual acuity was also significantly improved from 1.43 ± 0.35 preoperatively to -0.04 ± 0.18 logMAR postoperatively (p < 0.001). The mean binocular visual acuity was 0.01 logMAR or better at all distances (5.0, 3.0, 2.0, 1.0, 0.7, 0.5, and 0.3 m). All eyes were within ± 0.5 D of the targeted correction. All patients had within the normal range of near stereopsis. Neither cataract formation, significant intraocular pressure rise, nor vision-threatening complications occurred. Monovision by hole ICL implantation provided good binocular vision at near to far distances, without developing cataract, suggesting its feasibility as a new surgical presbyopic approach for early presbyopia.

Anterior segment optical coherence tomography angle and vault analysis after toric and non-toric implantable collamer lens V4c implantation in patients with high myopia

OBJECTIVE

To assess anterior segment changes, including iridocorneal angle and vault, after toric and non-toric implantable collamer lens (ICL) V4c (STAAR Surgical AG) implantation under different lighting conditions.

METHODS

Longitudinal, prospective, case series. Patients with high myopia (>6 dioptres) underwent toric and non-toric ICL V4c implantation. Optical coherence tomography measurements were taken under different lighting conditions preoperatively and at 1 week and 1, 6 and 12 months of follow-up.

RESULTS

Seventy-six eyes of 42 patients underwent ICL V4c implantation. Mean age was 27.4 years (±5.14 years, range 20 to 39 years). The average iridocorneal angle showed a statistically significant decrease (p<0.05) in all mesopic, scotopic and photopic conditions after 1 week of surgery compared with the preoperative measurements; in mesopic conditions, it decreased 14.1°, in photopic conditions 14.8° and scotopic conditions 13.2°. The angle measurement had a statistically significant change only in mesopic conditions (p=0.01) over the 1-year follow-up. The average vault under mesopic conditions was 0.661±0.21 mm at week 1. The vault measurement change was statistically significant over the 1-year follow-up in mesopic conditions (p=0.01). Refractive results showed a significant improvement in both uncorrected and corrected distance visual acuity (p<0.001).

CONCLUSION

There is a significant reduction in the iridocorneal angle after ICL V4c implantation. Furthermore, there is a change under mesopic conditions in both the iridocorneal angle and vault during long-term follow-up.

Comparison of corneal endothelial cell density and morphology after posterior chamber phakic intraocular lens implantation with and without a central hole

AIM

To compare the corneal endothelial cells after posterior chamber phakic intraocular lens with and without a central hole (hole implantable collamer lens (ICL) and conventional ICL) implantation for the correction of moderate to high myopia.

METHODS

This retrospective study evaluated 34 eyes of 34 patients who underwent hole ICL implantation and 25 eyes of 25 patients who underwent conventional ICL implantation. Preoperatively and 3 months, and 1 and 2 years postoperatively, we compared the central corneal endothelial cell density (ECD), coefficient of variation in cell size (CV) and the percentage of hexagonal cells (HEX) between the two groups using a non-contact specular microscope (EM-3000, Tomey). Preoperatively and 2 years postoperatively, we also compared them in the peripheral regions.

RESULTS

The mean central ECD loss was 0.3% and 1.1%, 2 years after hole ICL and conventional ICL implantation, respectively (Mann-Whitney U test, p=0.72). There were no significant changes in central ECD, CV or HEX at any time points either after hole ICL or conventional ICL implantation, and a significant decrease only in terms of ECD in the superior regions after conventional ICL implantation.

CONCLUSIONS

Both ICLs do not induce a significant change in the density, polymegethism or polymorphism of corneal endothelial cells even 2 years postoperatively, except for the density in the superior regions after conventional ICL implantation. However, hole ICL implantation may have advantages over conventional ICL implantation only in terms of the density in the superior regions, possibly because preoperative laser iridotomies are unnecessary.

Clinical application of TICL implantation for ametropia following deep anterior lamellar keratoplasty for keratoconus: A CONSORT-compliant article

BACKGROUND

This study aimed to investigate the clinical application of phakic toric intraocular collamer lens (TICL) implantation in treating ametropia following deep anterior lamellar keratoplasty (DALK) for patients with keratoconus, especially the effectiveness and safety of high astigmatism and indications of TICL implantation after corneal transplantation.

METHODS

Using the self-controlled case series observation approach, 9 patients with ametropia (9 eyes) who underwent DALK surgery for keratoconus 1.5 years ago with stitches removed 3 months ago were kept under observation from May 2013 to April 2014 in Ophthalmic Center of Nanjing Drum Tower Hospital affiliated to Nanjing Medical University. TICL implantation was performed in all patients. The uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) were examined before surgery and 1 week, 6 months, 1 year, and 2 years after surgery. Corneal astigmatism, corneal thickness, anterior chamber depth, corneal endothelial cell density (ECD), and preoperative and postoperative intraocular pressures at different time points were measured. Intraoperative or postoperative complications of TICL implantation were observed, and the safety of the operation was evaluated.

RESULTS

The UCVA and BCVA in all operated eyes were better 6 months after surgery than before surgery. The spherical diopter and cylindrical diopter decreased to different degrees after surgery. Six months after surgery, the deviation of TICL axis in all operated eyes was less than 10 degrees, tending to be stable. No severe intraoperative or postoperative complication occurred.

CONCLUSION

TICL implantation was an optional choice for ametropia correction after DALK surgery, especially in patients with high astigmatism.

Comparison of Visian toric collamer lens and toric acrylic intraocular lens implantation for the treatment of myopia with astigmatism

Purpose

To compare the efficacy and outcome of phakic toric implantable collamer lens (TICL) and refractive clear lens extraction with AcrySof Toric intraocular lens (TIOL) implantation for the treatment of myopic astigmatism.

Patients and methods

This study assessed eyes with myopic astigmatism >−1 D and ≤−4 D with a spherical equivalent >10 D or <10 D if the patients were unsuitable for corneal refractive surgery. These eyes were divided into group A, in which Visian Toric ICL™ Phakic TICL was implanted, and group B, which involved clear lens extraction with implantation of an AcrySof IQ toric SN60T3-9™ IOL. The outcome and complications were evaluated.

Results

This study enrolled 63 eyes of 38 patients with a follow-up period of at least 6 months. The mean postoperative spherical equivalent was −0.19±0.31 D in group A and −0.21±0.28 D in group B (P=0.69). The mean postoperative cylinder value was −0.46±0.53 D in group A and −0.32±0.41 D in group B (P=0.35). Postoperative cylinder was <1 D in 76.47% and 79.31% of eyes in groups A and B, respectively. The mean endothelial cell count was reduced by 4.32% in group A and by 5.32% in group B (P=0.003). The mean postoperative intraocular pressure increased insignificantly in group A (P=0.22) and reduced significantly in group B (P=0.004). The complication rate was 11.76% in group A and 6.90% in group B.

Conclusion

Both procedures showed predictable results and good visual results. However, the loss of accommodation and risk of retinal complications in the TIOL group suggest that the use of TICL for myopic astigmatism is a better choice in younger patients.

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.

Five-year functional outcomes and vault of -20 diopter myopic phakic intraocular lens implantation

PURPOSE

To evaluate refractive and visual outcomes and complications associated with phakic intraocular lens (pIOL) implantation to correct high myopia.

SETTINGS

Fernández-Vega Ophthalmological Institute, Oviedo, Spain.

DESIGN

Retrospective observational case series.

METHODS

Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), refraction, vault, and adverse effects were evaluated after 5 years with Visian ICMV4 pIOL.

RESULTS

Mean spherical equivalent (SE) dropped from -18.32 ± 2.37 diopters (D) preoperatively to -0.88 ± 0.52D 5 years postoperatively; 61% of eyes were within ±0.75 D of the target. The mean Snellen decimal CDVA and UDVA were 0.73 ± 0.23 and 0.55 ± 0.26, respectively. More than 50% of eyes achieved 20/25 or better CDVA postoperatively. Four eyes had lost 2 or 1 lines of CDVA, 10 eyes had not lost any lines from preoperatively, and 46 eyes had gained 1 or more lines of CDVA 5 years postoperatively. The safety index was 1.26 ± 0.32. Forty eyes had UDVA of 20/40 or better postoperatively. The efficacy index was 0.99 ± 0.42. At 5-year follow-up, the mean central vault was 475.28 ± 216.38 μm. No eyes showed central contact between the pIOL and crystalline lens. Nevertheless, 10 eyes showed peripheral contact with a central vault between 150 and 260 μm. Two eyes developed anterior subcapsular cataract, although only 1 eye required cataract surgery.

CONCLUSIONS

Predictability, safety and effective outcomes of posterior pIOL of (- were good, as well as postoperative complications over the long term. A central vault of 260 μm was enough to prevent the peripheral contact between the pIOL and crystalline lens in eyes with high myopia.

FINANCIAL DISCLOSURE

The authors have no proprietary interest in any of the materials mentioned in this article.

Simulated prototype of posterior chamber phakic intraocular lens for presbyopia correction

PURPOSE

To evaluate the visual impact of adding different spherical aberration values to an Implantable Collamer Lens phakic intraocular lens (pIOL) to increase the depth of focus using an adaptive optics visual simulator.

SETTING

University of Valencia, Valencia, Spain.

DESIGN

Experimental study.

METHODS

Wavefront aberrations in -3.00 D and -6.00 diopter (D) pIOLs were measured in vitro. Afterward, different simulated pIOL experimental prototypes were created along with variances in the spherical aberration. An adaptive optics visual simulator was used to simulate vision after the implantation of the different pIOL prototypes from their wavefront aberrations. The corrected distance visual acuity (CDVA) and depth of focus were measured in 3.0 and 4.5 mm pupils.

RESULTS

In a 3.0 mm pupil, the CDVA achieved with -3.00 and -6.00 D pIOLs and all pIOL prototypes evaluated was above 20/20 except for a -6.00 D pIOL + spherical aberration 4 at 50% CDVA contrast, which decreased to 20/25. However, in a 4.5 mm pupil, the CDVA obtained with the pIOL prototypes decreased significantly and was more pronounced when the spherical aberration induced was negative. The depth of focus increment was larger with the highest spherical aberration added and with a small pupil. Nevertheless, it was independent of the sign of the added spherical aberration.

CONCLUSIONS

The outcomes show that residual negative spherical aberration after pIOL implantation will disrupt the CDVA. However, some residual positive spherical aberration after pIOL implantation increased the depth of focus with excellent CDVA, providing a possible pIOL design for young presbyopic patients.

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.

Long-term ultrasound biomicroscopy observation of position changes of a copolymer posterior chamber phakic intraocular lens

PURPOSE

To evaluate longitudinal changes in Implantable Collamer Lens phakic intraocular lens (pIOL) position after implantation.

SETTING

Department of Ophthalmology, Zhejiang University, Hangzhou, China.

DESIGN

Retrospective case series.

METHODS

Myopic eyes that had pIOL implantation with a follow-up of at least 24 months were evaluated. Ultrasound biomicroscopy examinations were performed at each visit.

RESULTS

The study enrolled 62 eyes (31 patients; 22 women, 9 men) ranging in age from 21 to 46 years. The manifest spherical equivalent ranged from -8.25 to -18.75 diopters. A significant increase (mean 36 μm±50 [SD]) in the endothelium-anterior pIOL distance occurred between 1 month and 3 months (P=.000); afterward, the distance decreased slowly (P>.05). The largest decrease (mean 47±17 μm) in central vault occurred between 1 month and 3 months (P=.009). The largest decrease (mean 21±14 μm) in peripheral vault occurred between 1 month and 3 months (P=.000).

CONCLUSIONS

A significant increase in the endothelium-anterior pIOL distance occurred from 1 month to 3 months postoperatively, after which a slight decrease occurred over time. Central vault and peripheral vault had a tendency to decrease over time.

FINANCIAL DISCLOSURE

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

Causes of elevated intraocular pressure following implantation of phakic intraocular lenses for myopia

The purpose of this study is to present the causes and visual acuity outcomes in patients with elevated intraocular pressure (IOP) following implantable collamer lens (ICL) implantation. A chart review identified patients who developed high IOP at any postoperative examination and a minimum follow-up period of 3 months after ICL implantation. Data are reported out to 6 months postoperatively. Outcome measures included causes of elevated IOP, best-corrected visual acuity (BCVA) at last visit, number of glaucoma medications, other interventions, and glaucomatous damage. Elevated IOP occurred in 58 (10.8 %) of 534 eyes that received ICL. The mean age was 28 ± 7.2 years. The preoperative IOP was 16.3 ± 1.2 mmHg. Elevated IOP most commonly occurred on the first postoperative day (23/58 (39.7 %) eyes) due to retained viscoelastic. This was followed by steroid response in 22/58 (37.9 %) eyes at 2-4 weeks postoperatively. IOP elevation in 6 (10.3 %) eyes was related to high ICL vault and pupillary block, and in 4 (6.9 %) eyes due to synechial angle closure. At last visit, BCVA was 20/40 or better in 56/58 (96.6 %) eyes, and 5/58 (8.6 %) eyes remained on glaucoma medications due to persistent steroid response (2 eyes), synechial angle closure glaucoma (1 eye), and other causes (2 eyes). One eye showed glaucomatous damage. Two eyes with high vault and elevated IOP underwent ICL explantation. There is a moderate risk of transiently developing elevated IOP after ICL implantation. Thorough removal of viscoelastic and use of anti-glaucoma medications during steroid use will reduce the majority of cases with postoperative IOP elevation.

Dynamic vaulting changes in V4c versus V4 posterior chamber phakic lenses under differing lighting conditions

PURPOSE

To compare vaulting changes in eyes implanted with V4c and V4 implantable collamer lenses (ICLs) under differing lighting conditions.

DESIGN

Noninterventional, cross-sectional comparative observational case series.

METHODS

Fifty-six eyes of 38 patients implanted with V4c ICLs, and 54 eyes of 28 patients implanted with V4 ICLs were enrolled and analyzed. Anterior chamber depth, pupil size and postoperative vaulting were evaluated using a Visante optical coherence tomography system under photopic and mesopic conditions 1 month postoperatively. Refractive errors, keratometry values, axial lengths, intraocular pressures, anterior chamber volumes, and central corneal thicknesses were also recorded.

RESULTS

No significant differences were noted in anterior chamber depth between photopic and mesopic conditions in either group. Significant decreases in vaulting and pupil size were detected under photopic conditions in both groups. Moreover, vaulting changes in eyes implanted with V4c ICLs were significantly larger than those in eyes implanted with V4 ICLs.

CONCLUSIONS

V4c ICL vaulting decreased more prominently under photopic conditions than did V4 ICL vaulting. Therefore, postoperative vaulting under mesopic and photopic conditions should be considered when interpreting the vaulting of eyes implanted with V4c ICLs.

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.

Pre-operative visual evaluation for implantable collamer lenses in highly myopic eyes

PURPOSE

The aim of this study was to evaluate a clinical procedure based on trial rigid gas-permeable (RGP) contact lenses fitting to assess the real pre-operative visual acuity (VA) of highly myopic eyes undergoing surgery with an implantable collamer lens.

METHODS

Highly myopic eyes with a spectacle visual acuity (SVA) of 0.2 logMAR (6/9.6 Snellen) or worse were enrolled. A trial RGP contact lens with high dioptric power was fitted before collamer lens implantation. The trial contact lens residual refractive error was corrected by spectacle over-refraction to estimate contact lens VA (CLVA). The three-month post-operative uncorrected vision and visual acuities were also measured. The safety and efficacy indices of collamer lens implantation were calculated based on pre-operative SVA and CLVA, respectively.

RESULTS

The study enrolled 42 patients with 68 highly myopic eyes with a mean pre-operative spherical equivalent of -16.40 ± 4.43 D. The mean pre-operative SVA was 0.38 ± 0.19 logMAR. Pre-operative trial RGP contact lens fitting resulted in a significant improvement of VA (2.02 ± 1.05 lines), which was statistically insignificantly different from the VA with the implantable collamer lens (2.07 ± 0.8 lines). The safety index of collamer lens implantation was 1.70 ± 0.38 in reference to the pre-operative SVA but significantly decreased to 1.02 ± 0.17 in reference to CLVA. Similarly, the efficacy index of 1.17 ± 0.48 on SVA decreased to 0.71 ± 0.28 on CLVA.

CONCLUSIONS

Trial RGP contact lens fitting was found to indicate the potential implantable collamer lens VA more accurately than spectacle refraction. Consideration should be given to the use a trial RGP contact lens as part of the pre-operative work-up prior to collamer lens implantation in order to provide an assessment of the patient's potential post-operative VA.

Implantable collamer lens versus iris-fixed phakic intraocular lens implantation to correct myopia: a meta-analysis

This study is a meta-analysis comparing the efficacy, predictability, and safety of correcting myopia via implantation of two types of phakic intraocular lens (PIOLs): the implantable collamer lens (ICL) and iris-fixed PIOL. The Cochrane library, Pubmed, and EMBASE were searched. Study selection, data exclusion, and quality assessment were performed by two independent observers. The pooled relative risk (RR), pooled standardized mean difference (SMD), and their 95% confidence intervals (CIs) were used to compare lenses. Seven studies, involving 511 eyes, were included. The pooled SMD in postoperative uncorrected distance visual acuity (UDVA) comparing ICLs to iris-fixed PIOLs was −0.22 (95% CI, −0.58 to 0.13; P = .22). The pooled RR values of UDVA of 20/20 or better and of 20/40 or better comparing ICLs to iris-fixed PIOLs were 1.15 (95% CI, 0.89 to 1.47; P = .29) and 1.01 (95% CI, 0.95 to 1.08; P = .75), respectively. The pooled RR of loss of best spectacle-corrected visual acuity (BSCVA) and gain in BSCVA comparing ICLs to iris-fixed PIOLs were 1.20 (95% CI, 0.24 to 6.00; P = .82) and 1.14 (95% CI, 0.89 to 1.48; P = .31), respectively. The pooled RR comparing ICLs to iris-fixed PIOLs was 0.78 (95% CI, 0.29 to 2.12; P = .63) for all reported complications and 2.80 (95% CI, 1.04 to 7.52; P = .04) for severe complications. The pooled RR of achieving a result within ±0.5 D (diopter) of the intended target comparing ICLs to iris-fixed PIOLs was 1.35 (95% CI, 1.04 to 1.77; P = .03). Overall, there is no significant difference in efficacy between the two types of PIOLs or in safety, except that the ICL is associated with a greater incidence of severe complications, especially anterior subcapsular cataract, primarily in the Version 2 and Version 3 groups. However, ICL has better predictability.