Anatomical and functional outcomes of Boston type I keratoprosthesis as primary penetrating corneal procedure in high-risk and non-high-risk cases.

PURPOSE: To analyze the anatomical and functional results of Boston type I keratoprosthesis (B1-KPro) as a primary corneal procedure in high-risk (HR) cases and non-high-risk (NHR) cases. METHODS: In this retrospective interventional case series, all patients who underwent B1-KPro at a single center between January 2006 and March 2021 were reviewed and identified. Cases were classified according to the primary diagnosis. Anatomical failure was considered in the case of prosthesis extrusion or phthisis bulbi. Functional failure was a postoperative corrected distance visual acuity (CDVA) ≥ 1.3 LogMAR (≤ 0.05 decimal) at the end of the follow-up period. RESULTS: Twenty-three eyes were included for analysis. Thirteen eyes were classified as HR and 10 as NHR. The mean age was 46.5 ± 26.5 years (5-84 years) in the HR group and 49.5 ± 26.9 years (2-78 years) in the NHR group. The mean follow-up was 42.0 ± 35.9 months (1.5-118 months) in HR and 44.8 ± 38.8 months (1-107 months) in NHR. Three eyes in the HR and none in the NHR group showed anatomical failure. Functional failure was reported in 5/13 eyes in the HR and 8/10 in the NHR group. Functional cumulative survival probability was 92% and 82% for the HR group at 1 and 2 years, respectively. In the NHR group, it was 27% at both times. No significant differences were found between groups, except for functional survival in the HR group due to better visual potential of the eyes. CONCLUSIONS: B1-KPro as a primary corneal procedure is a valid option for visual rehabilitation in high-risk cases.

Soemmerring's Rings Developed around IOLs, in Human Donor Eyes, Can Present Internal Transparent Areas.

Soemmerring's rings consist of a ring of lens epithelial derived cells that grow along the periphery of an aphakic lens capsule, or around an intraocular lens. These rings when visualized frontally, appear opaque, however, in some cases the cells that compose these rings are organized in the same fashion as those in normal transparent adult lenses. Thus, our purpose was to test whether any part of the adult Soemmerring's ring could be transparent and how this related to morphological factors. To study this, 16 Soemmerring's rings were extracted from donor eye globes. After imaging, they were thickly sectioned sagittally in order to analyze the degrees of transparency of different areas. All samples were also histologically analyzed using alpha smooth muscle actin, Vimentin, wheat germ agglutinin and DAPI. Our results showed that many samples had some transparent areas, mostly towards the center of their cross-section. Of the factors that we analyzed, only lens fiber organization at the bow region and an increased area of mature lens fiber cells had a significant relation to the degree of transparency at the center. Thus, we can conclude that as Soemmerring's rings mature, they can develop organized and transparent areas of lens cells.

VITRECTOMY FOR ENDOPHTHALMITIS IN EYES WITH OSTEOKERATOPROSTHESIS.

PURPOSE: To analyze functional and anatomical results of pars plana vitrectomy (PPV) to treat endophthalmitis in eyes with osteokeratoprosthesis. METHODS: An observational, retrospective study of five eyes suffering from endophthalmitis, after an osteokeratoprosthesis implantation, which underwent PPV associated with intravitreal antibiotics. The minimum follow-up after PPV was 6 months. A descriptive study and a Kaplan-Meier survival analysis for anatomical (attached retina during the follow-up) and functional success (visual acuity ≥20/400) were performed. RESULTS: Best-corrected visual acuity during the final follow-up was 20/100 in 1 case (20%), hand movement in another case (20%), and no light perception in 3 cases (60%). The anatomical survival rates were recorded at 80%, 60%, and 40% at 1, 6, and 8 months respectively, and this last value was maintained at 12 months after PPV. The functional survival rates were recorded at 40% and 20% at 1 month and 8 months, respectively, and this last value was maintained at 12 months after PPV. CONCLUSION: Endophthalmitis in eyes with previous osteokeratoprosthesis is a very severe complication with a reserved prognosis. Pars plana vitrectomy associated with intravitreal antibiotics leads to maintaining or increasing visual acuity in a small proportion of patients who otherwise would end up blind.

Histological comparison of in vitro and in vivo development of peripheral posterior capsule opacification in human donor tissue.

In order to study the mechanisms involved in the development of posterior capsule opacification (PCO) we compared in vivo developed PCO with PCO formed in tissue culture with focus on the periphery of the lens capsule to evaluate lens regeneration potential. We studied three human tissue groups: Cultured lens capsules after mock cataract surgery (n = 6, 30 days), lens capsules from donors that had previously undergone cataract surgery (IOL capsules) (n = 12) and intact lenses (n = 6). All samples were stained with Vimentin, alpha Smooth Muscle Actin, Picro Sirius Red (for collagen) and Paired box protein (Pax6). We found that cultured capsules and less developed IOL capsules consisted mainly of monolayers of mesenchymal cells, while more developed IOL capsules, contained lens epithelial cells (LECs), globular cells and lens fiber cells. Many IOL capsule samples expressed collagen I and III in areas where cells were in contact with the IOL. Pax6 had a similar dispersed distribution in less developed IOL capsules and cultured capsules, while more developed IOL capsules and intact lenses, concentrated Pax6 in LECs at the equatorial lens bow. The similarities between cultured capsules and less developed IOL capsules indicate that our in vitro developed PCO is comparable to early in vivo developed PCO. The similar morphology of more developed IOL capsules and intact lenses seems to indicate an attempt at lens regeneration.

Cortical Cataract and Refractive Error.

PURPOSE: To evaluate the relationship between the presence of cortical cataract and accommodation effort, using refractive error as a proxy. METHODS: Patients between 50 and 90 years, scheduled for cataract surgery, were selected with the help of a photographic database. Nuclear and cortical cataract were graded and patients grouped having no cataract, pure cortical, mixed or pure nuclear cataract. Refraction data at the time of the photograph was converted to estimated spherical equivalent refractive error each patient would have had at the age of 45 years. RESULTS: From the initial 239 eyes from 239 patients, cases with myopia below -6.5 dpt and hyperopia above 6.5 dpt were excluded, resulting in 199 cases for final analysis. Eyes with no cataract showed the lowest median refractive error (-3.65 dpt), followed by the pure nuclear group (-2.69 dpt). The median refractive error for pure cortical (-0.23 dpt) and mixed cataracts (-0.87 dpt) were close to emmetropia. Cortical cataracts were found in 37% of myopes, 82% of emmetropes, and 85% of hyperopes. CONCLUSION: Emmetropes and hyperopes tend to develop more cortical cataract than myopes. These cortical cataracts might be caused by shear stress inside the crystalline lens due to accommodation efforts at the time of onset of presbyopia.

Anterior lens capsule strains during simulated accommodation in porcine eyes.

Experimental protocols have been developed to measure the spatial variation of the mechanical strains induced in the lens capsule during ex vivo lens stretching. The paper describes the application of these protocols to porcine lenses. The deformations and mechanical strains developed in the anterior capsule during each experiment were determined using full field digital image correlation techniques, by means of a speckle pattern applied to the lens surface. Several speckling techniques and illumination methods were assessed before a suitable combination was found. Additional data on the cross section shape of the anterior lens surface were obtained by Scheimpflug photography, to provide a means of correcting for lens curvature effects in the determination of the strains developed in the plane of the capsule. The capsule strains in porcine lenses exhibit non-linear behaviour, and hysteresis during loading and unloading. Peripheral regions experience higher magnitude strains than regions near the lens pole. The paper demonstrates the successful application of a procedure to make direct measurements of capsule strains simultaneously with ex vivo radial lens stretching. This experimental technique is applicable to future investigations on the mechanical characteristics of human lenses.

RESULTS OF RETINAL DETACHMENT SURGERY IN EYES WITH OSTEO-KERATOPROSTHESIS.

PURPOSE: To evaluate the anatomical and functional results of pars plana vitrectomy in eyes with osteo-keratoprosthesis, who have suffered retinal detachment. METHODS: An observational, retrospective study of 18 eyes which underwent pars plana vitrectomy for retinal detachment after an implantation of an osteo-keratoprosthesis, with a minimum of 1-year follow-up. A descriptive study and a Kaplan-Meier survival analysis for anatomical and functional success were performed. Anatomical success was defined as an attached retina at the end of vitreoretinal surgery with no redetachment during the follow-up. Functional success was defined as a postoperative visual acuity of more than or equal to 20/400. RESULTS: The overall rate of anatomical success was 56%, and the anatomical survival rates were 67% and 53% at 6 months and 12 months, respectively, maintaining this last value at 24 months after pars plana vitrectomy. The overall rate of functional success was 17%, and the functional survival rates were 83%, 39%, and 14% at 6 months, 12 months, and 24 months after pars plana vitrectomy, respectively. The most frequent complication after retinal surgery was retroprosthetic membrane (33%). CONCLUSION: Despite the reserved prognosis and the severe complications, vitrectomy represents a valid method for treating retinal detachment in patients with osteo-keratoprosthesis, with good anatomical results but poor visual acuity.

Validation of the Nuclear Cataract Grading System BCN 10.

PURPOSE: To evaluate a new nuclear cataract grading system which is intended as a surgical guidance system to predict lens hardness before cataract surgery. METHODS: The new BCN 10 grading system consists of frontal and cross-sectional slit-lamp images of human eye lenses, ranging from a completely transparent lens nucleus to a totally black nuclear cataract. Validation was done with 9 observers for 110 cases. Two modalities were applied, and observers were asked to use only whole digits and then half digits for grading. RESULTS: Repeatability with regard to test-retest differences showed a mean limit of agreement of 1.70 for whole digits and 1.32 for half digits. The absolute test-retest difference was close to zero for low as well high degrees of cataracts. Reliability for the entire group of 9 observers yielded an intraclass correlation coefficient which was within the same confidence interval, i.e., 0.991-0.995, for whole digits and half digits. CONCLUSIONS: BCN 10 grading repeatability was not affected by the severity of the cataract. It showed very good repeatability. Repeatability was significantly higher when the observers used half digits compared to whole digits. Reliability was found to be very good as well, independently of the use of whole or half digits.

Protein profiles in cortical and nuclear regions of aged human donor lenses: A confocal Raman microspectroscopic and imaging study.

A combination of Raman spectroscopy, imaging, hierarchical cluster analysis (HCA) and peak ratio analysis was used to analyze protein profiles in the superficial cortex (SC), deep cortex (DC) and nucleus of old human lenses with cortical, nuclear and mixed cataracts. No consistent differences were observed in protein spectra and after cluster analysis between the three locations irrespective of the presence or absence of cortical opacities and/or coloration. A sharp increase (∼15%-∼33%) in protein content from SC to DC, normal for human lenses, was found in 7 lenses. In 4 lenses, characterized by the absence of cortical opacities, the SC has a protein content of ∼35%. A significant increase in the disulfide-to-protein ratio is found only in the SC of the 7 cortical cataracts. No changes were found in sulfhydryl-to-protein ratio. The relative contents of α-helices and ß-sheets increase from SC to nucleus. ß-Sheets are more common in the SC of lenses with cortical cataract. The absence of significant and consistent changes in protein profiles between nucleus and cortex even in cases of severe coloration is not favoring the prevailing concept that ubiquitous protein oxidation is a key factor for age related nuclear (ARN) cataracts. The observations favor the idea that multilamellar bodies or protein aggregates at very low volume densities are responsible for the rise in Mie light scatter as a main cause of ARN cataracts leaving the short-range-order of the fiber cytoplasm largely intact. The absence of significant changes in the protein spectra of the deep cortical opacities, milky white as a result of the presence of vesicle-like features, indicate they are packed with relatively undisturbed crystallins.

Histopathology Findings of Corneal Buttons in Congenital Aniridia Patients.

PURPOSE: To evaluate the corneal button of primary penetrating keratoplasty of patients diagnosed with congenital aniridia. The study took place at the Instituto Universitario Barraquer and the Centro de Oftalmología Barraquer. METHODS: A retrospective analysis of cases diagnosed with congenital aniridia was carried out. We analyzed 13 corneal buttons of 11 eyes with congenital aniridia. We only included those patients who underwent penetrating keratoplasty for the first time. The corneal buttons were analyzed for histological characteristics of the presence of vascularization, the presence or not of Bowman's layer, the thickness of the stroma and Descemet's membrane, and endothelium layer alterations. RESULTS: We found alterations in the epithelium and stroma in all patients, although this loss of architecture was not seen in Descemet's membrane and the endothelial population. CONCLUSION: Patients with advanced congenital aniridic keratopathy may be good candidates for deep or superficial anterior lamellar keratoplasty for the preservation of normal endothelium and Descemet's membrane, along with limbal stem cell transplantation, to address epithelial and stromal pathology.

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.

Absence of amyloid-beta in lenses of Alzheimer patients: a confocal Raman microspectroscopic study.

We have compared the protein profiles in plaques and tangles in the hippocampus of post-mortem Alzheimer brains and in opaque and clear regions in the deep cortex of eye lenses of the same donors. From the 7 Alzheimer donors studied, 1 had pronounced bilateral cortical lens opacities, 1 moderate and 5 only minor or no cortical opacities. We focused on beta-sheet levels, a hallmarking property of amyloid-beta, the major protein of plaques and tau protein, the major protein of tangles in Alzheimer brains. Confocal Raman microspectroscopy and imaging was used in combination with hierarchical cluster analysis. Plaques and tangles show high levels of beta-sheets with a beta-sheet to protein ratio of 1.67. This ratio is 1.12 in unaffected brain tissue surrounding the plaques and tangles. In the lenses this ratio is 1.17 independently of the presence or absence of opacities. This major difference in beta-sheet conformation between hippocampus and lens is supported by Congo red and immunostaining of amyloid-beta and tau which were positive for plaques and tangles in the hippocampus but fully negative for the lens irrespective of the presence or absence of opacities. In line with a previous study (Michael et al., 2013) we conclude that cortical lens opacities are not typical for Alzheimer patients and are not hallmarked by accumulation of amyloid-beta, and can thus not be considered as predictors or indicators of Alzheimer disease as claimed by Goldstein et al. (2003).

Anatomical survival and visual prognosis of Boston type I keratoprosthesis in challenging cases.

PURPOSE: To describe the outcome of patients with Boston type 1 keratoprosthesis, with regard to anatomical and visual success. METHODS: Retrospective case series of patients who underwent Boston type I keratoprosthesis surgery at the Centro de Oftalmología Barraquer in Barcelona and at the University Eye Clinic in Salzburg between May 2006 and December 2011. Sixty-seven eyes were included. Anatomical success, visual acuity, and complication rate were evaluated and correlated with the initial diagnosis. RESULTS: The mean age of patients was 54 years; 62 % were male and 38 % were female. Eleven patients underwent Type I Boston Kpro implantation as a primary procedure, while the other 52 patients had previous graft failure. The most frequent diagnoses were autoimmune diseases (16 eyes), severe chemical or thermal burn (12 eyes), leukoma post-infectious keratitis (seven eyes) and bullous keratopathy (six eyes). The mean follow-up time was 26 months. Retention of the prosthesis was achieved in 95 % at 1 year and 78 % at 4.5 years. Two eyes suffered extrusion of the KPro, six underwent successful exchange of the prosthesis either due to infection, necrosis or extrusion, three KPro's had to be explantated, and two eyes ended up in enucleation due to panophthalmitis. The outcome of the autoimmune cases was similar to the group with "other diagnoses" and better than those with chemical/thermal burn. The most frequent complication was development of a retroprosthetic membrane in 21 eyes (34 %). Visual acuity (LogMAR) in the chemical/thermal burn group was 2.30 preoperatively, 0.69 at 1 year, 0.52 at 2 years and 0.39 at 3 years; in the autoimmune group visual acuity was 2.3 preoperatively, 0.65 at 1 year, 0.15 at 2 years, and 1.5 at 3 years. CONCLUSIONS: Boston type 1 keratoprosthesis is a viable option for patients with repeated graft failure, even for those with challenging diagnoses such as ocular burns and autoimmune syndromes.

Influence of primary diagnosis and complications on visual outcome in patients receiving a Boston type 1 keratoprosthesis.

PURPOSE: To analyse how primary diagnosis and complications affect the evolution of post-operative visual acuity (VA). METHODS: We performed retrospective chart analysis on 59 eyes in 57 patients with various diagnoses, most of which were non-standard indications for Boston type 1 keratoprosthesis (Kpro) implantation. The follow-up period was at least 3 months. Patients were classified based on the evolution of post-operative VA: group A demonstrated stable VA improvement, group B lost VA improvement and group C no significant VA improvement. RESULTS: We assigned 46% of our cases to group A with stable VA improvement, 32% to group B with lost VA improvement, and 22% to group C with no VA improvement. The number of graft failures before Kpro implantation did not influence VA outcome. Except for the relatively good VA outcome in chemical burn and radiation injury patients, there seems to be no association between primary diagnosis and positive or negative VA outcome. Only 9% of patients with posterior segment complications and 20% with infections and associated pathologies were assigned to group A. CONCLUSION: Most cases (78%) showed improvement in VA after Boston type 1 Kpro (groups A and B). Posterior segment complications and infections mostly resulted in persistent loss of vision. These complications should be prevented and carefully treated.

Endothelial Involvement in Monocular Mpox Keratitis: In Vivo Confocal Microscopy Approach.

PURPOSE: The aim of this study was to describe the clinical features and endothelial involvement in a case of Mpox virus keratitis by in vivo confocal microscopy (IVCM). METHODS: This is a case report. RESULTS: A 35-year-old man presented with redness, photophobia, pain, tearing, and a low visual acuity of 0.09 (decimal) in the left eye with a 6-week history of Mpox and corneal trauma. Previous testing of blood, interdigital skin lesions, and conjunctival and eyelid margin swabs confirmed the presence of Mpox by polymerase chain reaction. Biomicroscopy displayed superficial stromal infiltrates with a continuous but irregular epithelium. IVCM revealed the presence of pseudoguttata, loss of defined cell boundaries, infiltration of inflammatory cells in the endothelial layer, endothelial ridges, and precipitated pigmented granules, consistent with endotheliitis. After this episode, the patient had 4 reactivations, also treated with topical corticoids and oral tecovirimat 600 mg twice a day for 2 weeks. On the fourth reactivation, this treatment was extended to 4 weeks. On the last visit, the patient presented a visual acuity of 0.5 with disciform keratitis and reduced endotheliitis signs. The endothelial cell density remained normal during the follow-up (2763 ± 376 cell/mm 2 at baseline and 2795 ± 238 cell/mm 2 at the last visit). Polymegathism and pleomorphism showed altered values during the follow-up. CONCLUSIONS: Patients with an altered corneal epithelial barrier could suffer Mpox endotheliitis, like other DNA viruses, before disciform keratitis appears. IVCM is a useful tool for the early detection of endotheliitis and for describing its evolution, improving patient care.

Correction: Refractive changes of a new asymmetric intracorneal ring segment with variable thickness and base width: A 2D finite-element model.

[This corrects the article DOI: 10.1371/journal.pone.0257222.].

XEN45 Implant in Medically Controlled vs. Uncontrolled Eyes-Differential IOP Changes in Real-Life Conditions.

Background: To assess intraocular pressure (IOP) changes and complications after XEN45 implants in medically controlled eyes (MCE) vs. medically uncontrolled eyes (MUE). Methods: A retrospective study, in a tertiary referral hospital, on mild-to-moderate primary open-angle glaucoma (POAG) cases under topical medication, including 32 eyes with IOP < 21 mmHg (MCE group) and 30 eyes with IOP ≥ 21 mmHg (MUE group). The success criteria using Kaplan-Meier analysis was IOP < 21 mmHg without medications (complete success) or fewer drugs than preoperatively (qualified success) at the last visit, without new surgery or unresolved hypotony. Results: No significant preoperative differences were found between the groups. The mean IOP was 15.6 ± 3.8 mmHg in MCE and 15.1 ± 4.1 mmHg in the MUE group (p > 0.05; Mann-Whitney test) at the end of the follow-up (mean of 26.1 ± 15.6 months and 28.3 ± 15.3 months, respectively) (p = 0.414, Mann-Whitney Test). The device caused a significant IOP reduction at 24 h in both groups. Thereafter, the MCE group significantly tended to increase IOP, recovering baseline values at 1 month and maintaining them until the end of the follow-up. In contrast, in the MUE group, the IOP values tended to be similar after the first reduction. No relevant complications and no significant differences between the groups in the survival analysis were found. Conclusions: XEN45 provided stable IOP control in both the MCE and MUE group without important complications in the medium term. The IOP increasing in the MCE group, after a prior decrease, led to restored baseline values 1 month after surgery. The homeostatic mechanism that causes the rise in the IOP to baseline values and its relationship with failure cases remains to be clarified.

Absence of beta-amyloid in cortical cataracts of donors with and without Alzheimer's disease.

Eye lenses from human donors with and without Alzheimer's disease (AD) were studied to evaluate the presence of amyloid in cortical cataract. We obtained 39 lenses from 21 postmortem donors with AD and 15 lenses from age-matched controls provided by the Banco de Ojos para Tratamientos de la Ceguera (Barcelona, Spain). For 17 donors, AD was clinically diagnosed by general physicians and for 4 donors the AD diagnosis was neuropathologically confirmed. Of the 21 donors with AD, 6 had pronounced bilateral cortical lens opacities and 15 only minor or no cortical opacities. As controls, 7 donors with pronounced cortical opacities and 8 donors with almost transparent lenses were selected. All lenses were photographed in a dark field stereomicroscope. Histological sections were analyzed using a standard and a more sensitive Congo red protocol, thioflavin staining and beta-amyloid immunohistochemistry. Brain tissue from two donors, one with cerebral amyloid angiopathy and another with advanced AD-related changes and one cornea with lattice dystrophy were used as positive controls for the staining techniques. Thioflavin, standard and modified Congo red staining were positive in the control brain tissues and in the dystrophic cornea. Beta-amyloid immunohistochemistry was positive in the brain tissues but not in the cornea sample. Lenses from control and AD donors were, without exception, negative after Congo red, thioflavin, and beta-amyloid immunohistochemical staining. The results of the positive control tissues correspond well with known observations in AD, amyloid angiopathy and corneas with lattice dystrophy. The absence of staining in AD and control lenses with the techniques employed lead us to conclude that there is no beta-amyloid in lenses from donors with AD or in control cortical cataracts. The inconsistency with previous studies of Goldstein et al. (2003) and Moncaster et al. (2010), both of which demonstrated positive Congo red, thioflavin, and beta-amyloid immunohistochemical staining in AD and Down syndrome lenses, is discussed.

Resolving refractive error after cataract surgery: IOL exchange, piggyback lens, or LASIK.

PURPOSE: To evaluate the efficacy, predictability, and safety of three different procedures (intraocular lens [IOL] exchange, piggyback lens implantation, and LASIK) to correct residual refractive error following cataract surgery. METHODS: A retrospective multicenter study comprised 65 eyes of 54 patients that underwent phacoemulsification, resulting in a unacceptable final refractive error. Eyes were divided into three groups: eyes that had an IOL lens exchange (17 eyes), eyes that had a piggyback lens implanted (20 eyes), and eyes that had LASIK (28 eyes). RESULTS: No differences between the IOL exchange and piggyback lens groups in the spherical equivalent, sphere, or cylinder were found (P = .072, .436, and .081, respectively). The LASIK group showed a statistically significant reduction in spherical equivalent and refractive cylinder when compared with the IOL exchange group (P < .001 and P = .001, respectively). The LASIK group showed statistically significant reduced refractive cylinder in comparison with the piggyback lens group (P = .002). The median efficacy index was 0.58 (range: 0.28 to 0.93), 0.75 (range: 0.65 to 0.92), and 0.91 (range: 0.85 to 1.14) in the IOL exchange, piggyback lens, and LASIK groups, respectively. Statistically significant differences were found between the IOL exchange and LASIK groups (P = .004) and the piggyback lens and LASIK groups (P = .003). No statistically significant differences were detected in the safety index among groups (P = .094). The predictability (±1 diopters of final spherical equivalent) was 62.5% of eyes in the IOL exchange group, 85% of eyes in the piggyback lens group, and 100% of eyes in the LASIK group. CONCLUSIONS: The three procedures were effective. The LASIK group showed the best outcomes in efficacy and predictability.

Perioperative complications and clinical outcomes of intraocular lens exchange in patients with opacified lenses.

BACKGROUND: To evaluate the perioperative complications and the outcomes of intraocular lens (IOL) exchange in patients with opacified lenses. METHODS: Retrospective multicentrical consecutive series of cases that comprised 22 eyes from 21 patients who had previous phacoemulsification with implantation of an IOL in the capsular bag and developed severe late opacification of the IOL. All patients had loss of vision and reported light disturbances. The IOLs were explanted and replaced with new IOLs. The perioperative complications were evaluated. The best spectacle-corrected visual acuity (BSCVA) before and after the surgery was compared. RESULTS: The mean time lapsed between the original cataract surgery and the IOL exchange surgery was 89.1 ± 33.6 [48-216] months. The IOL exchange was uneventful in 14 eyes (63.6 %). Anterior vitrectomy was needed in seven cases (31.8 %). Other complications included zonular dehiscence in one case (4.5 %). In most of the cases, 14 eyes (63.6 %), the IOL was implanted in the sulcus. The most explanted IOL was the Hydroview H60M (Bausch & Lomb). The mean BSCVA (LogMAR) before and after the surgery were 0.57 ± 0.69 (0.10-3) and 0.18 ± 0.22 (0.0-1.10) respectively (t paired test, p < 0.001). After the operation, 20 eyes (90.9 %) achieved a BSCVA ≤ 0.3. No eye lost 1 or more lines of corrected vision after the surgery. CONCLUSIONS: IOL exchange surgery, although associated with a high incidence of complications, restores and significantly improves the visual acuity of patients with opacified IOLs.