Intraocular optical quality of phakic intraocular lenses: comparison of angle-supported, iris-fixated, and posterior chamber 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.

Evaluation of Visual Outcome of 2 Phakic Posterior Chamber Implantable Lenses in High Myopia: A Comparative Study

PURPOSE

To evaluate and compare the visual outcomes of two phakic intraocular lenses in high myopia.

METHODS

A prospective comparative study was undertaken on 50 eyes of 26 patients {age ≥21 years and divided into two groups (implantable collamer lens [ICL] V4c, n=25 eyes and refractive implantable lens [RIL], n=25 eyes)}. Patients were evaluated for uncorrected distance visual acuity (UCVA), best-corrected distance visual acuity, manifest refractive spherical equivalent (MRSE), contrast sensitivity, intraocular pressure, dilated fundus examination, trabecular-iris angle (TIA), anterior chamber depth, horizontal white-to-white diameter, wavefront aberrometry, and endothelial cell (EC) count. All patients were followed up until 6 months and additionally evaluated for anterior chamber inflammation, cataract, and lens vault.

RESULTS

The baseline parameters (UCVA, MRSE, and EC count) and postoperative improvement in UCVA, contrast sensitivity, MRSE, EC loss, safety index, and efficacy index were comparable between both the lenses. The improvement in aberrometric profile was significantly better in the ICL group. The mean postoperative vault was higher in RIL group (434.88±162.48 μm vs. 547.24±159.83 μm, P=0.0173); however, the vault was within normal range in both the groups. The decrease in mean TIA was significantly higher in RIL group (8.58 vs. 13.45 μm, P=0.0073).

CONCLUSION

Acrylic phakic lens can be considered as a suitable alternative to collamer lens for refractive correction of high myopia. The collamer lenses showed slight superiority in some qualitative visual parameters; however, collamer lenses do not present with subjective complaints in the patients.

Visual and Refractive Outcomes With the Eyecryl Phakic Toric IOL Versus the Visian Toric Implantable Collamer Lens: Results of a 2-Year Prospective Comparative Study

PURPOSE

To compare the 2-year visual and refractive outcomes with the Eyecryl Phakic Toric IOL (EP TIOL) (Biotech Vision Care Pvt Ltd) and Visian Toric ICL (TICL) (STAAR Surgical) for correction of high myopic astigmatism.

METHODS

This prospective, interventional, non-randomized comparison study included eligible patients who underwent toric phakic IOL surgery in one or both eyes with either the EP TIOL or TICL for myopic astigmatism. Two years postoperatively, both lenses were compared for their safety, efficacy, stability, and patient satisfaction. Vector analysis of astigmatism was performed using the Alpins method with the ASSORT software (ASSORT Party Ltd).

RESULTS

A total of 50 eyes were included, of which 25 eyes received EP TIOL implantation and the remaining 25 received TICL implantation. Preoperative mean ± standard deviation of spherical equivalent (SE) and cylinder was -10.15 ± 4.04 and -2.08 ± 0.86 diopters (D) in the EP TIOL group and -10.21 ± 3.97 and -2.17 ± 0.95 D in the TICL group, respectively. At 2 years of follow-up, there was no significant difference between the mean uncorrected distance visual acuity, corrected distance visual acuity, spherical equivalent, and residual astigmatism between the two groups (P > .05 for all parameters). Ninety-two percent of eyes in the EP TIOL group and 88% of eyes in the TICL group were within ±0.50 D of refractive astigmatism. Vector analysis of astigmatism showed a comparable Correction Index of 0.98 in the EP TIOL group and 0.94 in the TICL group, signifying a mild undercorrection of 2% and 6%, respectively. Two eyes in the TICL group underwent exchange for high vault and one eye required realignment due to significant postoperative rotation.

CONCLUSIONS

At least for the first 2 years postoperatively, both toric phakic IOLs were safe and effective in managing high myopic astigmatism with comparable visual results and patient satisfaction. [J Refract Surg. 2021;37(1):7-15.].

Comparison of the visual performance of iris-fixated phakic lens and implantable collamer lens to correct high myopia

Background

To compare visual performance between the iris-fixated phakic intraocular len (pIOL) and implantable collamer len (ICL) to correct high myopia.

Methods

Twenty-four eyes underwent iris-fixated pIOL implantation and 24 eyes underwent ICL implantation. At the 6-month follow-up, the best-corrected visual acuity (BCVA) and uncorrected distance visual acuity (UDVA) were compared between the iris-fixated pIOL and ICL groups. The objective scatter index (OSI), modulation transfer function (MTF) cutoff, and ocular aberrations were performed to evaluate postoperative visual quality between the two groups.

Results

No significant difference was found in UDVA, BCVA, and spherical equivalent between the iris-fixated pIOL and ICL groups (P > 0.05). Six months after surgery, the following values were significantly higher in the ICL group than in the iris-fixated pIOL group: MTF cutoff, strehl ratio and optical quality analysis system values at contrasts of 9 %, 20 %, and 100 % (P < 0.01). The OSI in the iris-fixated pIOL group was higher than in the ICL group 6 months after surgery (P < 0.01). All high-order aberrations were slightly more severe in the iris-fixated pIOL group than in the ICL group 6 months after surgery, although only trefoil (P = 0.023) differed significantly in this regard.

Conclusions

Both iris-fixated lenses and ICLs can provide good visual acuity. ICLs confer better visual performance in MTF-associated parameters and induce less intraocular light scattering than iris-fixated pIOLs.

Artisan versus Artiflex phakic intraocular lens implantation in the treatment of moderate to high myopia: meta-analysis

Background

To compare the postoperative safety, efficacy, predictability, visual quality and biomechanics after implantation of Artisan vs. Artiflex phakic intraocular lenses (PIOLs).

Methods

Pubmed, Embase, Cochrane Library were conducted up from January 2000 to February 2020. Comparative clinical studies reporting in accordance with the eligibility criteria were included in this meta-analysis. The pooled weighted mean differences (WMDs) and odds ratios (ORs) with corresponding 95% confidence intervals were calculated.

Results

Comparative trials with myopia patients were selected in this review. The pooled WMD and OR estimates statistical significance in terms of postoperative best corrected visual acuity (BCVA), efficacy, postoperative spherical equivalence (SE), predictability, contrast sensitivity and mean intraocular higher-order aberrations (HOA) (mm) for a 6-mm pupil, manifesting that Artiflex PIOL showed evident beneficial effect for correcting myopia compared to Artisan PIOL. There was no significant difference in the incidence of complications between the two groups.

Conclusion

Both of two techniques were safe and effective for myopia and compared to Artisan PIOL, Artiflex PIOL had significant improvement in efficacy, predictability, contrast sensitivityand HOA, except safety and complications in the treatment of moderate to high myopia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01930-6.

Long-Term Destiny of Corneal Endothelial Cells in Anterior Chamber Intraocular Lens-Implanted Eyes

Purpose

To investigate the long-term changes of corneal endothelial cells (EC) in anterior chamber intraocular lens- (AC-IOL-) implanted eyes.

Methods

Retrospective study. We included 37 eyes (25 patients) that received AC-IOL implantation previously in the Eye and ENT Hospital of Fudan University between 1995 and 2016. Follow-up outcomes included the best-corrected visual acuity (BCVA), endothelial cell density, hexagonality, coefficient of variance, and central corneal thickness.

Results

In total, 23 eyes (62.16%) with phakic and 14 eyes (37.84%) with aphakic AC-IOLs were included. Among these, 3 eyes (8.11%) were angle-supported AC-IOLs and 34 eyes (91.89%) were Artisan iris-fixated AC-IOLs. The mean age of patients was 41.40 ± 17.17 years, and the mean follow-up time was 12.12 ± 4.71 years in our study. At the follow-up time, corneal decompensation existed in 3 angle-supported AC-IOL eyes with a rate of 100% and 15 iris-fixated AC-IOL eyes with a rate of 44.12%. AC-IOL displacement occurred in 14 (41.18%) iris-fixated AC-IOL eyes. In the 19 iris-fixated AC-IOL eyes without corneal decompensation, significant changes also took place in corneal endothelial cells. The endothelial cell density decreased from 2843.26 ± 300.76 to 2015.58 ± 567.99 cells/mm² (29.1% loss, P < 0.001) and hexagonality decreased from 51.21 ± 7.83 to 42.53 ± 9.17 (%) (16.9% loss, P < 0.001). The Kaplan–Meier survival curve also demonstrated the accumulated expectation rates of corneal endothelial cell decomposition for AC-IOLs with a median survival time of 12 years.

Conclusion

We reported a significant chronic loss and long-term decompensation destiny of corneal endothelial cells in AC-IOL eyes. Semiannual or annual follow-up and evaluation of endothelial cells should be conducted in AC-IOL-implanted patients.

Phakic intraocular lens implantation for the correction of hyperopia

The prevalence of myopia is much higher than hyperopia. Hence, there are relatively few studies investigating phakic intraocular lens (pIOL) implantation for the correction of hyperopia. This review aimed to summarize the available relevant literature on the efficacy and safety of pIOL implantation for the correction of hyperopia and hyperopic astigmatism. At present, two types of pIOLs are used to correct hyperopia and hyperopic astigmatism: anterior chamber iris-fixated pIOLs and posterior chamber implantable collamer lenses. Both have been found to be safe and effective. No serious events (eg, retinal or choroidal detachment, endophthalmitis) were reported in the reviewed articles. Implantation of pIOLs might be the optimal refractive surgery for the correction of high hyperopia.

Descemet membrane endothelial keratoplasty for corneal decompensation caused by a phakic anterior chamber intraocular lens implantation

PURPOSE

To describe the clinical outcomes of Descemet membrane endothelial keratoplasty combined with phacoemulsification/posterior chamber intraocular lens implantation (triple procedure) for treatment of corneal decompensation induced by a phakic anterior chamber intraocular lens (AC IOL) implantation.

METHODS

Ten patients (10 eyes) with corneal decompensation due to phakic AC IOL implantation that had undergone the triple procedure were included in this study. Among the 10 eyes, 5 eyes underwent explantation of AC IOL prior to the transplantation, and then underwent the triple procedure. The remaining 5 eyes with a phakic AC IOL in situ underwent the triple procedure with concurrent explantation of AC IOL. Corrected distance visual acuity (CDVA), subjective refraction, endothelial cell density (ECD), and complications were documented.

RESULTS

The triple procedure was performed across all eyes without any adverse events. The average CDVA improved from 1.32 ± 0.24 preoperatively to 0.15 ± 0.05 logarithm of the minimum angle of resolution (logMAR), which represents an improvement in Snellen equivalent from 20/400 (0.05) preoperatively to 20/28 (0.71) at 12 months after surgery. At 12 months, all eyes reached a CDVA of 20/32 (0.63) or better, and 50% of eyes reached a CDVA of 20/25 (0.8) or better. The mean donor ECD±SD was 2868.7 ± 67.9 cells/mm², which decreased to 1724.1 ± 84.6 cells/mm² at 12 months, representing 39.9% of endothelial cell loss. Patients did not experience any severe adverse events.

CONCLUSION

The triple procedure is a safe and effective option for corneal decompensation induced by a phakic AC IOL implantation, helping achieve a satisfactory visual rehabilitation with few complications.

Explantation of phakic intraocular lenses: causes and outcomes

PURPOSE

To describe reasons for explantation of anterior and posterior chamber phakic intraocular lenses (pIOLs), as well as outcomes of the surgery.

METHODS

The medical files of patients who underwent pIOL explantation due to complications were reviewed. All patients were divided into three groups based on the type of explanted pIOL: anterior chamber angle-supported (AS pIOL), anterior chamber iris-fixated (IF pIOL), and posterior chamber (PC pIOL).

RESULTS

Sixty-two eyes of 41 patients were evaluated. There were 26 (41.9%), 16 (25.8%), and 20 (32.2%) eyes in the AS pIOL, IF pIOL, and PC pIOL groups, respectively. The mean interval between the implantation and removal of the pIOL (i.e., survival time) was 13.6 ± 8.1 years (range 0.01-21.22 years). The mean follow-up after the explantation was 22.5 ± 4.0 months (range 11.3-28.7 months). The main causes of explantation were cataract in the PC pIOL group (60%) and chronic endothelial cell loss in the AS pIOL group (53.8%) and IF pIOL group (56.2%). Overall, the procedure most often combined with pIOL explantation was phacoemulsification and implantation of a posterior chamber IOL (40.3%), followed by keratoplasty (9.6%). Intraoperative complications were significantly more common in the AS pIOL group than the other groups (p < 0.001).

CONCLUSIONS

Explantation of anterior chamber pIOLs due to severe endothelial cell loss and the proportion of keratoplasty was more common in patients with a relatively long survival time. Therefore, patients with pIOL implantation should be monitored regularly after surgery.

Comparison of rigid versus foldable iris-fixed phakic intraocular lens implantation for high myopia: A systematic review and meta-analysis

BACKGROUND

This study aimed to assess the efficacy of rigid versus foldable iris-fixed phakic intraocular lens (PIOL) implantation in the treatment of high myopia.

METHODS

A systematic search based on electronic databases such as Pubmed, Embase, and Cochrane Library was conducted to identify relevant studies published up to January 11, 2019. The pooled odds ratios and weighted mean differences (WMDs) with corresponding 95% confidence intervals were calculated.

RESULTS

Eight comparative studies with 835 participants were included in this meta-analysis. The overall WMD showed statistical significance in terms of postoperative uncorrected distance visual acuity (UDVA), mean postoperative spherical equivalence (SE), and mean postoperative intraocular higher-order aberrations (HOA) (μm) for a 6-mm pupil, suggesting that foldable PIOL group showed significant improvement of high myopia, compared to rigid PIOL group. Besides, compared with rigid PIOL group, foldable PIOL group had beneficial effect on the proportion of eyes with central endothelial cell density (ECD) loss in patients with high myopia.

CONCLUSION

This meta-analysis provided the up-to-date evidence and found that foldable PIOL group had significant beneficial effect on UDVA, SE, HOA, contrast sensitivity, and ECD, except best spectacle-corrected visual acuity, and safety in the treatment of high myopia over rigid PIOL group.

Intraocular pressure fluctuations in patients implanted with an implantable collamer lens (ICL V4c). Three-month follow-up

INTRODUCTION

Fluctuating elevated intraocular pressure (IOP) is one of the complications of an implantable collamer lens (ICL), and its alteration is a predictive factor for the development of glaucoma.

MATERIAL AND METHODS

A prospective, cross-sectional analytic study was conducted on patients suitable for ICL implantation. Complete clinical and biometric work-ups were performed, as well as night-time IOP curve, in supine position, with 4 determinations, in order to assess fluctuation, considering abnormal with a value higher than 5 mmHg. Patients underwent surgery with conventional technique and three months after the work-ups were repeated, including a night-time IOP curve to assess any changes in IOP fluctuations.

RESULTS

A total of 31 eyes of 16 patients were studied. Mean IOP fluctuation in the preoperative assessment was 3.35 ± 2 mmHg, whereas the postoperative mean was 3.0 ± 2.2 mmHg, with the difference not being statistically significant. Visual acuity and capacity, as well as spheric equivalent did show a statistically significant improvement. There were 6 cases of complications, which were related to a higher vault and a greater ICL size. There was no relationship between these findings and the angle grade, pigment, and the level of training of the surgeon.

CONCLUSIONS

The effect of an ICL on IOP fluctuations, has been studied for the first time, which was found to be not statistically significant. As in previous publications, the procedure was safe and reproducible, adding the fact that the level of training of the surgeon is not a determining factor in these findings.

Artiflex foldable lens for myopia correction results of 10 years of follow-up

PURPOSE

The aim of this study was to evaluate the long-term efficacy and safety of the Artiflex® lens implant and to follow the evolution of the number of corneal endothelial cells over time.

DESIGN

It was a retrospective study of an observational case series of patients who underwent surgery at "The INVISION Ophthalmic Hospital" (Almería, Spain) in 2007 and who were followed for 10 years.

METHODS

Setting: Clinical practice. Study population included 53 eyes of 30 patients who underwent an Artiflex® lens implant for the correction of myopia from -4 to -14 D. Each patient included in this study had stable myopia for at least 2 years and a contraindication for corneal refractive surgery. The efficacy index was defined as the quotient between uncorrected distance visual acuity postoperative and best-corrected distance visual acuity (BCDVA) preoperative. The safety index was calculated as the quotient between BCDVA postop and BCDVA preop.

RESULTS

The average efficacy and safety indices of the lenses implanted were 1.1 (SD 0.30) and 1.06 (SD 0.2) at 10 years of follow-up. In this period of time there has been a loss of 12% of the corneal endothelial cells. The postoperative complications were pigment dispersion in four eyes (7%) of four patients and decentration of phakic intraocular lens in two eyes (4%) of another two patients.

CONCLUSIONS

The Artiflex® foldable phakic lens could be a safe and effective long-term alternative for myopic patients in whom laser surgery was contraindicated.

Comparison of long-term decentration and tilt in two types of multifocal intraocular lenses with OPD-Scan III aberrometer

PURPOSE

To compare the long-term decentration and tilt in two multifocal intraocular lenses (MfIOLs) with an OPD-Scan III aberrometer.

METHODS

Eighty cataract patients who underwent uneventful MfIOL implantation (42 with AcrySof® IQ ReSTOR® SN6AD1 and 38 with AMO Tecnis® ZMB00) were enrolled. At 1 year after surgery, a postoperative visual acuity evaluation included the measurement of uncorrected distance visual acuity, corrected distance visual acuity, distance-corrected near visual acuity, and distance-corrected intermediate visual acuity. OPD-Scan III aberrometer was used to collect the decentration, tilt, and high-order aberration (HOA) data. Significance was tested with Student's t test, Mann-Whitney U test, paired t test, and χ² test RESULTS: The average intraocular tilt was lower in the SN6AD1 group than in the ZMB00 group, whereas the average decentration of the two groups did not differ significantly. The mean total ocular HOAs, ocular trefoil, total internal HOAs, and spherical aberrations were significantly lower in the SN6AD1 group than in the ZMB00 group. In both the SN6AD1 and ZMB00 groups, the intraocular tilt was directly proportional to the total ocular HOAs, coma, and spherical aberration. However, there was no significant correlation between decentration and any type of HOA in SN6AD1 group, whereas decentration correlated positively with total ocular HOAs, coma, and spherical aberration in ZMB00 group.

CONCLUSION

Both MfIOLs significantly improve the visual acuity of the patients. However, tilt was lower in the SN6AD1 group than in the ZMB00 group 1 year after surgery, which provide fewer HOAs and better visual quality.

One Year Follow-Up After Veriflex Phakic Intraocular Lenses Implantation for Correction of Myopia

Objectives:

The aim of this study was to evaluate visual and refractive outcomes after Veriflex phakic intraocular lenses (pIOL) implantation in moderately myopic eyes as well as postoperative complications.

Methods:

This prospective clinical study included 40 eyes of 26 patients which underwent implantation of Veriflex for correction of myopia from -6.00 to -14.50 diopters (D) in the Eye Clinic Svjetlost Sarajevo, from January 2011 to January 2014. Uncorrected distance visual acuity (UDVA), manifest residual spherical equivalent (MRSE), intraocular pressure (IOP), endothelial cell (EC) density were evaluated at one, three, six and 12 months. Other complications in postoperative period were evaluated. For statistical analysis SPSS for Windows and Microsoft Excel were used.

Results:

Out of 26 patients 14 had binocular and 12 monocular procedure, with mean age of 29.8±6.5 years. After 12 months mean UDVA was 0.73±0.20. Mean MRSE was -0.39±0.31D and 90% of eyes had MRSE within ±1D. EC loss was 7.18±4.33%. There was no significant change of IOP by the end of 12 months follow up period. The only intraoperative complication was hyphema and occurred in one eye. Few postoperative complications were: subclinical inflammation in three eyes (7,5%), pigment dispersion in four eyes (10%), ovalisation of papilla in 2 eyes (5%) and decentration of pIOL in 2 eyes (5%).

Conclusion:

Implantation of iris-claw phakic lenses Veriflex for treating moderately high myopia is a procedure with good visual and refractive results and few postoperative complications.

Phakic Intraocular Lenses and their Special Indications

Phakic intraocular lenses revolutionize refractive surgery and continue to serve as an excellent option for vision correction in patients who are not ideal candidates for laser vision correction. This article will review special indications of phakic intraocular lenses in the clinical practice.

Ultrasound biomicroscopy in chronic pseudophakic ocular inflammation associated with misplaced intraocular lens haptics

PURPOSE

To evaluate the usefulness of ultrasound biomicroscopy in confirming intraocular lens haptic-induced ocular irritation and in the management of these patients.

DESIGN

A retrospective review of patient data.

METHODS

Twenty pseudophakic patients who underwent ultrasound biomicroscopy examination between May 2009 and February 2011 to confirm the clinical suspicion of misplacement of intraocular lens haptics were reviewed. Ophthalmic findings at the time of presentation and at each follow-up visit, and management of each patient, were recorded.

RESULTS

Intraocular lens haptic misplacement was confirmed by ultrasound biomicroscopy in all suspected cases. In 75% of the eyes 1 haptic was embedded in the iris; it extended into the ciliary body process in 35% and into the pars plana in 10%. Focal iris thinning/atrophy was detected by ultrasound biomicroscopy in 15% of cases and focal angle closure in 25%. Intraocular lens exchange was performed in 40% of patients. The remaining 60% were kept under observation, with the addition of topical steroids and/or cycloplegics in eyes that demonstrated anterior chamber inflammation and intraocular pressure-lowering medications in eyes with persistent elevated intraocular pressure or glaucoma.

CONCLUSIONS

Ultrasound biomicroscopy appears to be a valuable tool in confirming the presence of haptic-induced ocular irritation and in assisting the management of these patients.