Angle-Supported Anterior Chamber Phakic Intraocular Lens ExplantationCauses and Outcome

Causes of intraocular pseudophakic lens explantation in Spain

PURPOSE

To report the causes of pseudophakic intraocular lens (IOL) explantation in Spain over a 20 year period.

METHODS

Multicenter observational prospective study of a consecutive series of cases corresponding to pseudophakic intraocular lenses explantations performed in 22 Spanish clinical centres from 2002 to 2021, within a national clinical research network. The clinical data of all IOL explantation patients was evaluated, and the different causes for IOL explantation were systematically analyzed.

RESULTS

From a total of 1013 pseudophakic explantations, 919 cases were included in this investigation. The mean age of the patients at the time of explantation was 66.3 years, and 142 (15.45%) were women. Over the 20 years of the study, the five main reasons for explanting lenses in the last 20 years in Spain according to the Iberia RETICS database were: dislocation / decentration / misalignment (43.08%), bullous keratopathy (16.79%), neuroadaptation failure (13.85%), IOL opacification (9.71%), refractive surprise (6.87%). Other causes, less frequent, were uveitis / endophthalmitis / infection with 39 cases (4.25%); IOL substitution for reasons other than multifocal IOL neuroadaptation failure 3 cases (0.33%); and other causes, 47 cases (5.13%). Hydrophobic lenses were the most frequently explanted with a ratio of 47.1%.

CONCLUSIONS

Over the 20 years of the study, the five main reasons for explanting lenses in the last 20 years in Spain according to the Iberia RETICS database were: dislocation / decentration / misalignment, bullous keratopathy, neuroadaptation failure, IOL opacification, and refractive surprise.

Iris-Claw Anterior Chamber Phakic Intraocular Lens Explantation: A Case Series

Purpose

To evaluate indications, clinic characteristics, and outcomes in a series of patients who underwent explantation of phakic intraocular lens (pIOL).

Methods

Retrospective case series of patients who underwent iris-claw pIOL explantation in our institution from 2018 to 2022. Indications for explantation and visual and refractive outcomes were analyzed.

Results

Twenty-three eyes of 14 patients underwent pIOL explantation with a mean time to explantation of 11.7 ± 3.4 years. The mean age at explantation was 46.0 ± 3.9 years. Sixteen Artisan and seven Artiflex IOL were explanted. The main indication for explantation was endothelial cell loss (n = 14) and morphometric significant alterations of endothelial cells other than endothelial cell count decline (n = 5). The mean corrected vision after explantation was 0.4 ± 0.4 logMAR, and around 70% of intervened patients achieved visual acuity of at least 0.3 logMAR (0.5 in decimal scale).

Conclusions

In our group series, the main reason for the removal of pIOL was endothelial cell loss. This complication should be monitored and followed, so that early actions, namely IOL explantation, can be performed to avoid the development of deterioration requiring corneal transplantation. In fact, loss of follow-up, found in several cases for many years, continues to be a serious problem.

Accuracy of Intraocular Lens Calculation Formulas in Patients Undergoing Combined Phakic Intraocular Lens Removal and Cataract Surgery

PURPOSE

To investigate the prediction accuracy of intraocular lens (IOL) calculation formulas, and the impact of anterior chamber depth (ACD) and lens thickness (LT) measurement errors on IOL power calculation in patients undergoing combined phakic IOL (PIOL) removal and cataract surgery.

DESIGN

Retrospective, consecutive case series study.

METHODS

Thirty-six PIOL implanted eyes (12 anterior chamber PIOLs and 24 posterior chamber PIOLs [PC-PIOL]) undergoing cataract surgery were included. The prediction accuracy of new formulas (Barrett universal II, Emmetropia verifying optical, Kane, and Ladas super formula) and traditional formulas (Haigis, Hoffer Q, Holladay 1 and SRK/T) with or without Wang-Koch (WK) axial length (AL) adjustment was evaluated. The influence of ACD and LT measurement errors of IOLMaster 700 on refractive outcomes was also investigated.

RESULTS

The Kane and traditional formulas with WK AL adjustment had no significant systematic prediction error and displayed a smaller median absolute error, whereas the other formulas showed significant hyperopia shift (P < .05) and relatively lower prediction accuracy. The accuracy rate of IOLMaster 700 in measuring the ACD and LT was 100% in eyes with anterior chamber PIOL implantation, and 37.50% in the PC-PIOL subgroup. No significant difference was observed in refractive outcomes of formulas using correct and wrong parameters in the PC-PIOL subgroup (P > .05).

CONCLUSIONS

The Kane and traditional formulas with WK AL adjustment exhibited relatively higher prediction accuracy in patients who underwent combined PIOL removal and cataract surgery. The IOLMaster 700 displayed low accuracy in ACD and LT measurements for PC-PIOL implanted eyes, but showed negligible impact on IOL prediction accuracy.

Short-Term Efficacy and Safety of Cataract Surgery Combined with Iris-Fixated Phakic Intraocular Lens Explantation: A Multicentre Study

The purpose of this study was to evaluate the short-term efficacy and safety of cataract surgery for patients with iris-fixated phakic intraocular lenses (pIOLs). This study included 96 eyes of 91 patients. The changes in the logMAR uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), subjective spherical equivalent (SE), astigmatism, and endothelial cell density (ECD) were collected retrospectively. The intraoperative and postoperative complications also were investigated to assess the surgical safety. The preoperative UCVA and BCVA improved significantly at month 1 postoperatively, respectively (p < 0.001 for both comparisons). The efficacy and safety index at month 1 postoperatively were 1.02 ± 0.56 and 1.31 ± 0.64, respectively. The SE at month 1 postoperatively was significantly (p < 0.001) higher compared to preoperatively, whereas the subjective astigmatism did not differ significantly (p = 0.078). The ECD significantly decreased at month 1 (p < 0.001). The most common postoperative complication was intraocular pressure elevation exceeding 25 mmHg in 10.4% of eyes, which was controlled with medications in all cases until month 1 postoperatively. No intraoperative complications developed. Cataract surgeries for patients with iris-fixated pIOLs were performed safely with good visual outcomes.

Refractive outcomes and complications following angle supported, iris fixated, and posterior chamber phakic intraocular lenses bilensectomy

PURPOSE OF REVIEW

The manuscript presents a review of published studies regarding the outcomes, causes, and complications of phakic intraocular lens (pIOLs) bilensectomy.All pIOLs will be explanted at some point, therefore is important to know the visual and refractive outcomes following bilensectomy.

RECENT FINDINGS

There are few publications about the outcomes following pIOL bilensectomy; in all of them, cataract remains the main cause of bilensectomy. Other causes are endothelial cell density loss and pupil ovalization. The mean time between pIOL implantation and bilensectomy is longer in eyes implanted with an anterior chamber pIOL than in eyes implanted with a posterior chamber pIOL. There is a significant improvement in uncorrected and corrected distance visual acuity after bilensectomy. Some sight-threatening complications like retinal detachment and low endothelial cell density (ECD) after surgery have been reported. Current publications suggest that endothelial cell density loss is more frequent in eyes that underwent bilensectomy for an anterior chamber pIOL.

SUMMARY

Good visual and refractive outcomes are achieved after bilensectomy, regular endothelial cell density measurements should be performed in all patients implanted with an anterior chamber pIOL to perform a safe bilensectomy.

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.

Long-term results of Descemet-stripping automated endothelial keratoplasty for endothelial failure caused by phakic intraocular lenses

PURPOSE

To describe the surgical approach and long-term outcomes of Descemet-stripping automated endothelial keratoplasty (DSAEK) for endothelial failure secondary to phakic intraocular lenses (pIOL).

METHODS

Retrospective, interventional case series of 18 eyes of 13 patients who developed endothelial failure secondary to pIOL implant. Patients were submitted to pIOL explant and DSAEK for visual rehabilitation, with or without phacoemulsification plus posterior-chamber intraocular lens implant. The minimum follow-up time was 3 years and the main outcome measures were best-corrected visual acuity (BCVA), endothelial cell density (ECD) and percentage of endothelial cell loss (ECL), intraoperative and postoperative complications.

RESULTS

Patients' mean age was 47.44 (7.86) years with a mean follow-up time of 55.61 (14.13) months. Sixteen eyes (88.9%) had an angle-supported pIOL. The mean pIOL implant-to explant time was 8.17 (2.73) years. BCVA improved from 1.00 (0.36) logMAR preoperatively to 0.29 (0.36) logMAR at 1 year of follow-up (p < 0.001), remaining stable over the entire follow-up period (p > 0.05). At the last visit, all corneas were clear, with a mean ECD of 724.74 (325.57) cells/mm². During the follow-up, two eyes (11.1%) required a re-DSAEK due to early graft failure (<3 months).

CONCLUSION

Our outcomes reveal that an individualized and careful approach may result in a stable visual rehabilitation in young patients with corneal decompensation following pIOL implant.

Iris-fixated phakic intraocular lens explantation

BACKGROUND/AIMS

To evaluate the visual outcomes and indication for surgery in a series of patients who underwent explantation of a phakic intraocular lens (PIOL).

METHODS

A retrospective case series of patients who underwent PIOL explantation in our institution was performed. The indication for explantation and visual and refractive outcomes were examined. The method of explantation is described.

RESULTS

Twenty-two eyes of 16 patients underwent PIOL explantation with a mean time to explantation of 7 ± 3 years (range 3-11.4). The mean age at explantation was 50.3 ± 9.3 years. Sixteen Artisan PIOLs and six Artiflex PIOLs were explanted. The indications for explanation were cataract development (17/22), endothelial cell loss (4/22) and synechiae formation (1/22). All patients with cataract underwent a combined procedure with explantation and phacoemulsification and the placement of a posterior chamber IOL. Mean corrected vision after explantation was 0.22 ± 0.10 logMAR (range 0.1-0.3 logMAR). One patient with endothelial cell loss required a Descemet's Stripping Endothelial Keratoplasty (DSEK).

CONCLUSION

Removal of PIOLs was necessitated most frequently by cataract followed by endothelial cell loss. Both explantation alone and explantation with concurrent phacoemulsification are safe procedures with good visual outcomes and will become more frequent in the future as more patients with PIOLs reach cataractous age.

Phakic intraocular lenses: Recent advances and innovations

Phakic intraocular lenses (pIOL) are recommended when counselling refractive surgery candidates presenting with high ametropia or ocular surface and/or corneal conditions that contraindicate corneal refractive surgery. This review aims to present the state-of-the-art regarding pIOL models currently available in Europe, addressing their newer indications and recent design innovations. These include, in the case of posterior chamber pIOLs, the addition of a central hole to improve aqueous humour circulation, the availability of larger optical zones, and multifocal optics for the compensation of presbyopia. The review also highlights their good safety and efficacy results, as well as the role of patient education to ensure adequate outcomes in the medium-long term. The indications of pIOLs in special situations, as well as bi-lensectomy, a procedure that most pIOL patients may eventually require as they age and develop cataracts, are also addressed.

Changes in symmetry of anterior chamber following routine cataract surgery in non-glaucomatous eyes

Background

To assess minimum and maximum changes in anterior chamber dimensions following routine cataract surgery in non-glaucomatous eyes.

Methods

Forty-two eyes (42 participants) underwent routine cataract surgery with same surgeon and were assessed preoperatively, 1, 3, 6 and 12 months postoperatively. Primary outcome measure: Angle-to-angle diameter (AAD) (at 0-180^o, 45-225^o, 90-270^o, 135-315^o), Anterior-chamber-angle (ACA) (at 0^o, 45^o, 90^o, 135^o, 180^o, 225^o, 270^o and 315^o) and central anterior chamber depth (ACD) at all visits. Secondary outcome measures: relationship to axial length (AL).

Results

The mean AAD and ACA increased post-operatively in all meridians at all visits postoperatively. At 12 months, there was a maximum change in AAD in horizontal meridian (506.55 ± 468.71 μm) and least in vertical meridian (256.31 ± 1082.3 μm). The mean percentage increase in ACA postoperatively was least at 90^o (5% increase compared to 29–35% elsewhere). Central ACD deepened at all postoperative visits and this did not change over 12 months. There was no correlation between AAD, ACA and ACD with AL at any visit.

Conclusion

The AAD, ACA and ACD increases following cataract surgery in non-glaucomatous eyes, but at 12 months increase in AAD is least in vertical compared to horizontal meridian. Also, ACA was narrower (only 5% increase) superiorly compared to elsewhere (29–35% increase in ACA). This may have implications with regards to surgeries performed in the anterior chamber and corneal endothelial cell loss.

Updates on Managements for Keratoconus

Purpose

Keratoconus is a progressive disease of the cornea which can lead to blindness as irregular astigmatism increases. Currently, a variety of methods are available for the treatment of keratoconus, and in certain cases, it may be difficult to choose the most appropriate option. This article reviews available treatment modalities for keratoconus to provide the practitioner with practical and useful information for selecting the most suitable option for each individual patient.

Methods

To review treatment methods for different stages of keratoconus, PubMed (United States National Library of Medicine) and Scopus (Elsevier BV) databases were searched using the keywords “keratoconus”, “contact lens”, “cross-linking”, “Intacs”, “keratoplasty”, “gene therapy”, and “irregular astigmatism”, and related articles were reviewed based on disease assessment parameters and treatment methods.

Results

Various methods are available for the treatment of keratoconus: eyeglasses and contact lenses in the early stages, cross-linking for stabilizing disease progression, intrastromal corneal ring segments (ICRS) for reducing refractive errors or flattening the cornea, and penetrating keratoplasty (PK) and deep anterior lamellar keratoplasty (DALK), conductive keratoplasty, gene therapy and more recently, bowman layer transplantation (BL transplantation) in advanced stages of the disease. To achieve optimum results, it is essential to choose the best option for each individual patient.

Conclusions

A commonality of the reviewed papers was the advancement of novel diagnostic and treatment methods in ophthalmology, which can delay the need for corneal grafting. A better understanding of keratoconus treatment options can help enhance visual rehabilitation and prevent blindness in keratoconus patients.

Phakic intraocular lens: Two-year results and comparison of endothelial cell loss with iris-fixated intraocular lenses

PURPOSE

To evaluate the efficacy, safety, and stability of a foldable angle-supported Acrysof Cachet phakic intraocular lens (pIOL) to correct moderate to high myopia and compare endothelial cell loss after iris-fixated Artisan and Artiflex pIOL implantation.

SETTING

University Eye Clinic Maastricht, the Netherlands.

DESIGN

Retrospective observational study.

METHODS

Foldable angle-supported pIOL implantation for myopia ranging from -6.0 to -16.5 diopters (D) was done. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity, spherical equivalent (SE), and adverse events were documented preoperatively and 6 months and 1 and 2 years postoperatively. Endothelial cell loss after implantation of the foldable angle-supported pIOL and iris-fixated pIOLs was compared 6 months and 1 and 2 years postoperatively.

RESULTS

There were 158 eyes. The UDVA was equal to or more than 20/25 in 95% of eyes at 1 and 2 years postoperatively. The mean SE was -0.17 D ± 0.43 (SD) 2 years postoperatively. One patient developed pupil ovalization, resulting in explantation of the pIOL from both eyes. Acute endothelial cell loss in the foldable angle-supported pIOL group was -3.2% ± 0.7%, significantly higher than after iris-fixated pIOL implantation. Chronic endothelial cell loss from 6 to 24 months after surgery was -3.8% ± 0.7%. At the 2-year follow-up, the chronic endothelial cell loss in the foldable angle-supported pIOL group was not different than with iris-fixated pIOLs (P > .05).

CONCLUSIONS

The foldable angle-supported pIOL effectively corrected moderate to high myopia. However, acute surgical endothelial cell loss was significantly higher than with iris-fixated pIOLs.

FINANCIAL DISCLOSURE

Dr. Nuijts is a consultant to Alcon Laboratories, Inc., Théa Pharma GmbH, and ASICO LLC; he has received study grants from Acufocus, Inc., Alcon Laboratories, Inc., Carl Zeiss Meditec AG, Ophtec BV, and Physiol S.A. No other author has a financial or proprietary interest in any material or method mentioned.

Long-Term Observation of Triplex Surgery for Cataract after Phakic 6H Implantation for Super High Myopia

Purpose. To analyze the safety, effectiveness, and stability of triplex surgery for phakic 6H anterior chamber phakic intraocular lens explantation and phacoemulsification with in-the-bag IOL implantation for super high myopia in long-term observations. Methods. This retrospective case series evaluated 16 eyes of 10 patients who underwent triplex surgery. Best corrected visual acuity (BCVA), endothelial cell density (ECD), and associated adverse events were evaluated. Results. The mean follow-up time after the triplex surgery was 46 ± 14 months. The mean logMAR BCVA was significantly improved after triplex surgery (P = 0.047). One eye developed endophthalmitis five days postoperatively and underwent pars plana vitrectomy (PPV). Five eyes with preoperative severe endothelial cell loss developed corneal decompensation and underwent keratoplasty at a mean time of 9.4 ± 2.6 months after the triplex surgery. One eye had graft failure and underwent a second keratoplasty. The eye developed rhegmatogenous retinal detachment and underwent PPV with silicone oil 18 months later. ECD before the triplex surgery was not significantly different compared with that at last follow-up (P = 0.495) apart from these five eyes. Three eyes (18.8%) developed posterior capsule opacification. Conclusions. Triplex surgery was safe and effective for phakic 6H related complicated cataracts. Early extraction before severe ECD loss is recommended.

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.

Combined endothelial keratoplasty and clear lens extraction for corneal decompensation in irido-corneal endothelial syndrome

A 38-year-old woman presented with corneal decompensation in left eye secondary to irido-corneal endothelial (ICE) syndrome. She underwent simultaneous Descemet's stripping endothelial keratoplasty (DSEK) and clear lens extraction with posterior chamber intraocular lens implantation. The surgery was accomplished comfortably without rupture of peripheral anterior synechiae (PAS). 5 weeks postoperatively, the graft was attached, the cornea was clear and best-corrected visual acuity improved from 20/400 to 20/30. DSEK combined with clear lens extraction appears to be an effective measure to treat corneal decompensation in patients with ICE syndrome. Associated lens extraction in such cases increases the working space in anterior chamber for DSEK, which minimizes the intra-operative graft manipulation. This also avoids a future difficult cataract surgery in the presence of PAS and an endothelial graft, which may increase the chances of graft survival.

Surgical Management of Iatrogenic Pigment Dispersion Glaucoma

INTRODUCTION

Iatrogenic pigment dispersion syndrome generally originates from a repetitive, mechanical trauma to the pigmented posterior epithelium of the iris. This trauma can arise after intraocular surgery, most commonly due to an abnormal contact between the intraocular lens (IOL) and the iris. Whether surgical removal of this primary insult can lead to a successful intraocular pressure (IOP) control remains unclear.

METHODS

Case-series. Patients with IOP elevation and clinical signs of pigment dispersion were screened for a diagnosis of iatrogenic IOL-related pigment dispersion.

RESULTS

Three patients in which the IOL or the IOL-bag complex caused a pigment dispersion through a repetitive iris chafing were selected. In two cases, replacement of a sulcus-based single-piece IOL (patient 1) or a sub-luxated in-the-bag IOL (patient 2) by an anterior-chamber (AC) iris-fixed IOL led to a sustained decrease in IOP. In the third case, extensive iris atrophy and poor anatomical AC parameters for IOL implantation precluded further surgical intervention.

CONCLUSION

IOL-exchange appears to be a useful tool in the management of iatrogenic pigment dispersion glaucoma due to inappropriate IOL implantation. This cause-oriented approach seems to be effective in controlling IOP, but should be offered only if safety criteria are met. How to cite this article: Van Mierlo C, Abegao Pinto L, Stalmans I. Surgical Management of Iatrogenic Pigment Dispersion Glaucoma. J Curr Glaucoma Pract 2015;9(1):28-32.

Phakic intraocular lens explantation: causes in 240 cases

PURPOSE

To describe the main causes of explantation of phakic intraocular lenses (PIOLs) according to the anatomical site of implantation (angle supported, iris fixated, or posterior chamber).

METHODS

This multicentric, retrospective, and consecutive study sponsored by the Spanish Ministry of Health comprised a total of 240 eyes (226 patients) explanted due to PIOL complications. Clinical data of 144 angle-supported lenses, 24 iris-fixated lenses, and 72 posterior chamber lenses explanted were recorded preoperatively and postoperatively.

RESULTS

Mean age of the patients at explantation was 46.30 ± 11.84 years (range: 25 to 80 years). The mean time between implantation and explantation was 381.14 ± 293.55 weeks (range: 0.00 to 1,551.17 weeks). It was 422.33 ± 287.81 weeks for the angle-supported group, 488.03 ± 351.95 weeks for the iris-fixated group, and 234.11 ± 4,221.60 weeks for the posterior chamber group. It was 8.10 ± 5.52 years for the angle-supported group, 9.36 ± 6.75 years for the iris-fixated group, and 4.49 ± 4.25 years for the posterior chamber group. This period of time was significantly shorter in the posterior chamber group (P < .001). Overall, the main causes of explantation were cataract formation (132 eyes, 55%), endothelial cell loss (26 eyes, 10.83%), corneal decompensation (22 eyes, 9.17%), PIOL dislocation/decentration (16 eyes, 6.67%), inadequate PIOL size or power (12 eyes, 5%), and pupil ovalization (10 cases, 4.17%). Cataract development was the cause of explantation in 51.39% of angle-supported cases, 45.83% of iris-fixated cases, and 65.28% of posterior chamber cases. Endothelial cell loss was the cause of explantation in 15.97% of angle-supported PIOLs, 8.33% of iris-fixated PIOLs, and 1.39% of posterior chamber PIOLs.

CONCLUSIONS

Cataract is the main cause of PIOL explantation, especially in posterior chamber PIOLs. In the angle-supported group, endothelial cell loss was the second cause of explantation.

Quadruple procedure for visual rehabilitation of endothelial decompensation following phakic intraocular lens implantation

PURPOSE

To evaluate the clinical outcomes of combined phakic intraocular lens (phakic IOL) explantation, phacoemulsification, posterior chamber intraocular lens (PCIOL) implantation, and Descemet stripping automated endothelial keratoplasty (DSAEK) performed for phakic IOL-related endothelial decompensation.

DESIGN

Retrospective, interventional case series.

METHODS

setting: Private hospital. study population: Ten eyes of 7 patients who developed endothelial decompensation after phakic IOL implantation and were treated with a combined procedure of phakic IOL explantation, phacoemulsification, PCIOL implantation, and DSAEK. main outcome measures: Best spectacle-corrected visual acuity (BSCVA), manifest refractive error, endothelial cell count, and intraoperative and postoperative complications.

RESULTS

Mean postoperative follow-up was 25.2 ± 28.6 months (range 3-84 months). BSCVA at last visit was 7/10 or better in 6 eyes, 4/10 in 1 eye, and 2/10 or worse in 3 eyes, of which all had myopic maculopathy or deep amblyopia. Mean postoperative spherical equivalent was -3.4 ± 1.2 diopters. Mean endothelial cell loss in comparison to preoperative donor endothelial cell density was 21.3% ± 7.7%. Minor PCIOL decentration was seen in 1 patient, and IOL exchange was required in another patient owing to high postoperative refractive error. One graft rejection leading to graft failure was seen and was excluded from endothelial cell loss calculation.

CONCLUSION

An operation combining phakic IOL removal, DSAEK, cataract removal, and PCIOL implantation can offer fast visual rehabilitation with good visual results and graft survival.

Anterior segment optical coherence tomography of long-term phakic angle-supported intraocular lenses

PURPOSE

To evaluate the long-term age-related anterior chamber changes by anterior segment optical coherence tomography (OCT) and the impact of such changes on the stability and behavior of angle-supported phakic intraocular lenses (IOLs).

DESIGN

A retrospective consecutive observational cohort study.

METHODS

A total of 23 eyes with high myopia implanted with an angle-supported phakic IOL between 1990 and 1996 at Vissum Corporación Oftalmológica de Alicante were included in the study. Patients were evaluated using OCT. Anterior chamber depth, anterior chamber width, crystalline lens rise, and the distance between phakic IOL and endothelium were measured.

RESULTS

Fifteen years after implantation, anterior chamber depth was 2.9 ± 0.3 mm, crystalline lens rise 748.18 ± 393.13 μm, and phakic IOL-endothelium distance 2.1 ± 0.30 mm. The predictive model showed that 30 years after implantation, endothelial cell count was less than 600 cells/mm(2) in patients with a preoperative spherical equivalent of -25 diopters (D). Twenty years after implantation, the safety zone of 1.5 mm between endothelium and the lens will not be respected in patients with a preoperative spherical equivalent of -20 D.

CONCLUSIONS

The findings of this study could have an important influence on the decision about the indication to implant angle-supported phakic IOLs in young patients with a long postoperative life expectancy, as age-related changes in the anatomy of the anterior segment may create a long-term hazard for the implanted eye.

Stability of cachet phakic intraocular lens position during 6-months follow-up

Purpose:

To evaluate the position stability of a phakic intraocular lens (Cachet pIOL; Alcon, Laboratories, Inc., Fort Worth, TX) in the anterior chamber (AC) during a 6-months follow-up.

Methods:

Thirty eyes of 16 subjects underwent a Cachet pIOL implantation for the correction of high myopia from -6.50 to -16.00 D with plano targeted refraction. The position stability of the Cachet pIOL was evaluated using an Anterior Segment-OCT (AS-OCT, Carl Zeiss AG, Oberkochen, Germany) at 1- and 6-months postoperatively. Three measurements have been taken into account: 1) the minimum distance between the anterior surface of the Cachet pIOL optic disk and the central corneal endothelium; 2) the minimum distance between the optic disk’s edges of the pIOL and the endothelium; 3) the minimum distance between the posterior surface of the pIOL optic disk and the anterior surface of the crystalline lens. The endothelial cell density (ECD) was also recorded.

Results:

No statistically significant changes of the Cachet pIOL position in the AC were found during follow-up. The average changes were ≤0.1 mm between 1- and 6-months postoperatively (P>0.05). At the end of follow-up, The mean ECD loss was 0.7 % (from 2794 ± 337 cell/mm² to 2776 ± 388 cell/mm²; P>0.05).

Conclusion:

A high position stability of the Cachet pIOL in the anterior chamber was shown during a 6-months follow-up.

Phakic anterior chamber lenses in very high myopia: an 18-month follow up

BACKGROUND

To evaluate the efficacy and tolerance of two different foldable anterior chamber phakic intraocular lenses for high myopia.

DESIGN

A prospective interventional case series at the Eye Clinic, Kartal Training and Research Hospital, Istanbul, Turkey.

PARTICIPANTS

Sixty-two eyes of 31 patients received iris-claw lens (group 1) (Artiflex AC 401, Ophtec), and 43 eyes of 22 patients received angle-supported lens (group 2) (I-Care, Corneal).

METHODS

The mean preoperative spherical equivalents for group 1 and group 2 were -12.13 D and -18.95 D, respectively. Endothelial cell density was measured at day 1 and at 1, 3, 6, 12 and 18 months for follow ups.

MAIN OUTCOME MEASURES

  Percentage change in endothelial cell density and improvement in visual acuity.

RESULTS

At the 18-months follow up, uncorrected visual acuity improved to logMAR 0.37 ± 0.23 from 1.60 ± 0.10 in group 1, and logMAR 0.47 ± 0.14 from 0.70 ± 0.20 in group 2; best spectacle corrected visual acuity improved to logMAR 0.23 ± 0.22 from logMAR 0.36 ± 0.14) in group 1, and logMAR 0.29 ± 0.18 from logMAR 0.50 ± 0.20) in group 2 (P<0.001, in both groups). Mean decreased endothelial cell density was 241 cells/mm(2) (8.61%) and 223 cells/mm(2) (8.42%) at 18 months follow up in group 1 and 2, respectively (P=0.17) but significant in comparison to preoperative values for both groups (P<0.001).

CONCLUSIONS

Although both iris-claw and angle-supported lenses offer good refractive outcomes significant endothelial cell density was observed at 18 months follow up.

Simultaneous bilensectomy and endothelial keratoplasty for angle-supported phakic intraocular lens-induced corneal decompensation

A 40-year-old lady presented with severe endothelial cell loss in both eyes 14 years after angle-supported phakic intraocular lens (AS PIOL) implantation. The left eye had severe corneal edema with bullous keratopathy. The right eye had markedly reduced endothelial cell count (655 cells/mm²) although the cornea was clear. She underwent simultaneous bilensectomy (AS PIOL explantation and phacoemulsification) and Descemet's stripping and endothelial keratoplasty (DSEK) in the left eye. Explanted AS PIOL was identified as ZSAL-4 (Morcher, Stuttgart, Germany) model. Corneal edema cleared completely in 2 months with a best corrected visual acuity (-2.25 D sph) of 20/60. No intervention was done in the right eye. The present case illustrates that AS PIOL-induced endothelial decompensation can be effectively managed by simultaneous bilensectomy and endothelial keratoplasty.

Toric phakic implantable collamer lens for correction of astigmatism: 1-year outcomes

Purpose:

The purpose of this study was to assess predictability, efficacy, safety and stability in patients who received a toric implantable collamer lens to correct moderate to high myopic astigmatism.

Methods:

Forty-three eyes of 23 patients underwent implantation of a toric implantable collamer lens (STAAR Surgical Inc) for astigmatism correction. Mean spherical refraction was −4. 98 ± 3.49 diopters (D) (range: 0 to −13 D), and mean cylinder was −2.62 ± 0.97 D (range: −1.00 to −5.00 D). Main outcomes measures evaluated during a 12-month follow-up included uncorrected visual acuity (UCVA), refraction, best-corrected visual acuity (BCVA), vault, and adverse events.

Results:

At 12 months the mean Snellen decimal UCVA was 0.87 ± 0.27 and mean BCVA was 0.94 ± 0.21, with an efficacy index of 1.05. More than 60% of the eyes gained ≥1 line of BCVA (17 eyes, safety index of 1.14). The treatment was highly predictable for spherical equivalent (r² = 0.99) and astigmatic components: J₀ (r² = 0.99) and J₄₅ (r² = 0.90). The mean spherical equivalent dropped from −7.29 ± 3.4 D to −0.17 ± 0.40 D at 12 months. Of the attempted spherical equivalent, 76.7% of the eyes were within ±0.50 D and 97.7% eyes were within ±1.00 D, respectively. For J₀ and J₄₅, 97.7% and 83.7% were within ±0.50 D, respectively.

Conclusion:

The results of the present study support the safety, efficacy, and predictability of toric implantable collamer lens implantation to treat moderate to high myopic astigmatism.

Artisan iris-supported phakic IOL implantation in patients with keratoconus: a review of 16 eyes

PURPOSE

To evaluate the clinical outcomes of Artisan phakic intraocular lens (PIOL; Ophtec BV) implantation in patients with stable keratoconus.

METHODS

In a prospective, nonrandomized case series, 14 Artisan PIOLs and 2 toric Artisan PIOLs were implanted in 13 patients (16 eyes) with stable keratoconus who had contact lens intolerance. Pre- and postoperative data were collected.

RESULTS

Mean follow-up was 14.2 ± 7.8 months. Preoperative uncorrected distance visual acuity (UDVA) was counting fingers in all patients. Mean final logMAR (Snellen equivalent) UDVA and corrected distance visual acuity (CDVA) were 0.15(20/28) ± 0.13 and 0.11(20/26) ± 0.10, respectively. The improvements in UDVA and CDVA were statistically significant (P<.0001 and P<.002, respectively). All patients achieved a final UDVA of 20/40 or better, and 84.6% had a final CDVA of 20/32 or better. No postoperative complications occurred except for two cases of sterile uveitis.

CONCLUSIONS

Implantation of the Artisan PIOL is effective in improving visual acuity in patients with stable keratoconus. Long-term safety remains to be established as no postoperative endothelial cell counts were performed.

Value of optical coherence tomography for anterior segment surgery

Anterior segment optical coherence tomography (AS-OCT) is an important new noncontact imaging technology that uses a 1310 nm super luminescent diode. It can be used to assess anterior chamber biometry, corneal thickness, lens thickness, and angle configuration; to visualize pathological processes; to evaluate postsurgical anatomy and posttraumatic eyes; and to image phakic intraocular lenses and intracorneal ring segments. Because it is a noncontact technique, it can also be used intraoperatively, which could be useful during trabeculectomy and after deep anterior lamellar keratoplasty to detect abnormalities in the cornea and interface. A disadvantage of AS-OCT is its inability to penetrate the iris pigment epithelium, which makes it impossible to evaluate the structures behind the iris. The most frequently used devices are time-domain AS-OCT, but new Fourier-domain OCT devices, which have faster image acquisition and higher resolution, are currently under investigation.

FINANCIAL DISCLOSURE

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

Refractive stability of LASIK with the Visx 20/20 excimer laser vs ZB5m phakic iol implantation in patients with high myopia (>-10.00 d): a 10-year retrospective study

PURPOSE

To compare the long-term outcomes of LASIK and ZB5M phakic intraocular lens implantation (PIOL) (Domilens) for high myopia (>-10.00 diopters [D]).

METHODS

This long-term (10 years) follow-up retrospective interventional case series study included 126 eyes that underwent LASIK and 52 eyes that underwent ZB5M angle-supported PIOL implantation. Both groups of eyes were similar in terms of preoperative spherical equivalent refraction (SE), corrected distance visual acuity (CDVA), and age.

RESULTS

Mean preoperative SE was -14.33 D in the LASIK group and -14.84 D in the PIOL group. At 10-year follow-up, mean postoperative SE was -1.47±2.00 D in the LASIK group and -1.01±1.36 D in the PIOL group (P=.21). In the LASIK group, 67% of eyes were within ±1.00 D of emmetropia at 2 years after surgery, compared to 42% at 10 years. In the PIOL group, 68% of eyes were within ±1.00 D of emmetropia 2 years after implantation compared to 53% at 10 years. In the LASIK group, 43.5% of eyes achieved UDVA of 20/40 or better 10 years after surgery compared to 67.9% in the PIOL group (P=.02).

CONCLUSIONS

The ZB5M angle-supported PIOL was shown to have better predictability and stability compared to LASIK over 10 years. However, reductions in endothelial cell count over time were observed in eyes with PIOLs.

Late postoperative complications of backward implantation of a Vivarte phakic intraocular lens

A 34-year-old man had bilateral implantation of a Vivarte phakic intraocular lens (pIOL) (Ciba Vision) to correct high myopia. Postoperatively, both pIOLs appeared to have been implanted backward. After a few weeks, the position of the pIOL in the right eye was corrected in a second procedure. For unknown reasons, the pIOL in the left eye was untouched. Three years after the initial implantation, the patient visited our hospital for a second opinion. He presented with a decrease in visual acuity from an intrapupillary membrane in the left eye. Endothelial cell count of the left cornea showed markedly decreased endothelial cell density. The patient was successfully treated by removing the IOL and excising the intrapupillary membrane, leading to recovery of visual acuity. This case presents the rare occurrence and management of late postoperative complications of backward implantation of a Vivarte pIOL.

Implants phakes de chambre antérieure versus chambre postérieure

At a time when some of the limitations of photoablation have been defined, such as worry concerning secondary ectasia, a renewed interest in phakic implantation has arisen. This is driven by the goal of avoiding correcting high ametropia with LASIK and is based on the development of soft foldable biomaterials. When all phakic IOLs are in front of the natural lens, two varieties of lenses can be distinguished, depending on whether it is located in the anterior or posterior chamber. The various models available in 2006 and those under current evaluation are reviewed. We do not report details of clinical studies that vary in cohort size and follow-up. The advantages and limitations are discussed for each type of phakic IOL. Adequate although not exclusive indications are deduced. There is no phakic lens that has proved to be superior to the others in terms of safety. All have the ability to provide a visual benefit with a gain in best corrected visual acuity. The difference is based on anatomical effects, requiring long-term follow-up in the evaluation of angles, lens, iris, and endothelium.

Optical Analysis of Visual Improvement after Correction of Anisometropic Amblyopia with a Phakic Intraocular Lens in Adult Patients

PURPOSE

To analyze possible reasons for an increase in visual acuity observed in myopic patients with anisometropic amblyopia after implantation of a phakic intraocular lens (PIOL) using a theoretical eye model.

DESIGN

Retrospective case series.

PARTICIPANTS

Fifty-nine eyes of 48 patients with anisometropic amblyopia implanted with an angle-supported PIOL.

METHODS

Inclusion criteria were anisometropia of at least 3 diopters (D) and a best spectacle-corrected visual acuity (BSCVA) of 0.7 or less in the best eye. Follow-up was performed at 1, 3, 6, and 12 months and then annually for up to 10 years. The theoretical analysis of mechanisms to explain the visual improvement was performed using a theoretical eye, based on the Kooijman model, in which the measured values of radii and thickness of the different surfaces were substituted. The magnification and spot size were calculated by a ray tracing process.

MAIN OUTCOME MEASURES

Uncorrected visual acuity, improvement in best spectacle-corrected visual acuity, and spherical equivalent.

RESULTS

Mean gain in visual acuity was 3 lines (range, 0-7 lines). Fifty-four eyes (91.5%) gained at least 1 line of visual acuity, whereas no eyes lost lines of vision. The change in BSCVA did not correlate with preoperative BSCVA (Pearson coefficient, r = 0.19) or with the degree of anisometropia (Pearson coefficient, r = 0.23). The calculations using a Kooijman eye model corrected with spectacles and with a PIOL accounted for the full increase in visual acuity in terms of the magnification (increased by a factor of 1.2) and the spot size (reduced by a factor of 2).

CONCLUSIONS

After implantation of a PIOL, the visual acuity of myopic patients with anisometropic amblyopia showed a significant increase. This increase was explained using a theoretical eye model not only in terms of magnification but also including changes in aberrations. An evident role of neuroprocessing in this visual improvement was not identified.