Refractive surgery after deep anterior lamellar keratoplasty: a review of the literature.

PURPOSE: The main objective of this work is to present an updated review of the different surgical procedures for the correction of residual refractive errors following deep anterior lamellar keratoplasty (DALK) surgery. METHODS: A review of the literature was conducted using PubMed, Web of Science, and Scopus databases. The search was conducted in January 2022 and was limited to articles published in peer-reviewed journals. The information extracted from each publication included sample size, mean follow-up time, pre- and post-operative uncorrected (UDVA) and corrected distance visual acuity (CDVA), pre- and post-operative refraction and spherical equivalent (SE), safety and efficacy indexes and complications. RESULTS: Residual ametropias, mainly high astigmatism and myopia, and the resulting anisometropia are likely to occur following DALK. They become a limiting factor and may lead to unsatisfactory visual restoration, therefore affecting patients' quality of vision and life. Alternative surgical interventions may be required to treat this residual ametropia, such as corneal refractive surgery or intraocular lens implantation. A total of 47 relevant articles were studied in detail. Different refractive surgery techniques have been shown to be effective and safe for the correction of ametropia following the DALK procedure and to improve the patient's quality of vision, although more research is needed to confirm long-term results. CONCLUSION: The final refractive technique will depend on different factors, such as the amount of ametropia, the condition of the cornea or the patient's individual needs, economics, and occupational demands.

Three-year follow-up of posterior chamber phakic intraocular lens with a central port design after deep anterior lamellar keratoplasty.

BACKGROUND: To evaluate clinical outcomes of the Visian implantable collamer lens (ICL) with a central port to correct myopia and astigmatism after deep anterior lamellar keratoplasty (DALK) for keratoconus throughout 3 years of follow-up. METHODS: This study included 20 eyes of 20 patients that underwent V4c ICL (13 eyes with a spherical ICL and 7 eyes with a toric ICL) implantation after DALK. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure (IOP), endothelial cell density (ECD), and vault were analyzed. RESULTS: The mean UDVA improved from the preoperative 1.18 ± 0.33 logMAR to 0.25 ± 0.14 logMAR at 6 months after surgery (P < 0.0001) and remained unchanged throughout the whole follow-up (P = 0.4). All eyes gained lines of CDVA compared to preoperative values. At the last follow-up visit, all eyes achieved CDVA of 0.2 logMAR or better and 13 eyes (65%) 0.1 logMAR or better. At 6 months post-surgery, all eyes (100%) had a spherical equivalent within ± 1.50 D, and 19 (95%) within ± 1.00 D. The mean manifest spherical equivalent was stable over the postoperative follow-up (P = 0.25). No significant increase in IOP occurred in any case throughout the 3 years of follow-up. The loss in ECD from the preoperative baseline at the last follow-up visit was 2.27%. CONCLUSIONS: The clinical outcomes suggest that the V4c ICL implantation for correction of myopia and regular astigmatism in post-DALK eyes was satisfactory in terms of effectiveness, safety, and stability during 3 years of follow-up.

Impedance-based non-invasive assay for ocular damage prediction on in vitro 3D reconstructed human corneal epithelium.

Reconstructed human cornea-like epithelium (RhCE) holds unprecedented promise for toxicological analyses and the replacement of animal use. However, current standards to evaluate potential ocular irritancy present a major downfall, the need to invasively alter tissue samples to evaluate cell viability. In this study, the applicability of impedance analysis was validated by monitoring the change in cell capacitance during tissue maturation and before and after chemical application using coupled electrodes. Our results indicate that cell maturation on RhCE models can be evaluated during model production using capacitance sensing offering a faster and simpler quality control criteria for RhCE model usability. Additionally, cell capacitance resulted to be more sensitive in detecting slight cell damages than methods based on cell metabolism, and when integrated into OECD-approved testing strategies, capacitance sensing performed as good as currently accepted methodologies displaying 66% sensitivity, 100% specificity and 83% accuracy when evaluated at 300 Hz. In summary, a quantitative analysis to predict in vivo ocular irritation based on changes in RhCE capacitance by impedance spectroscopy is suggested. This methodology represents a non-invasive and non-destructive alternative that would enable the monitoring of reversible effects or repeated dose toxicity.

Mini Cleanroom for the Manufacture of Advanced Therapy Medicinal Products (ATMP): Bioengineered Corneal Epithelium.

Among several requirements for the manufacture of Advanced Therapy Medicinal Products (ATMP) are: following the guidelines of a pharmaceutical quality system, complying with Good Manufacturing Practice (GMP) and access to a cleanroom fulfilling strict environmental conditions (Class A work area and Class B environment). This makes ATMP expensive. Moreover, the production of many of these therapeutic products may also be unprofitable, as in most cases their use is limited to a few patients and to a single batch per manufacturing unit. To reduce costs, ATMP may be produced in a scaled-down system isolated from the external environment (isolator), allowing for placement of this facility in a Class D environment, which is much more permissive and less costly. In this work, we confirm that it is possible to manufacture bioengineered corneal epithelium inside an isolator while fulfilling all the safety assurance standards at an affordable cost for patients. This small-scale ultra-clean working environment complies with GMP guidelines and could be a solution for the high costs associated with conventional cleanroom ATMP production.

Use of Plasma Rich in Growth Factors and ReGeneraTing Agent Matrix for the Treatment of Corneal Diseases.

This study aimed to investigate the use of Plasma Rich in Growth Factors (PRGF) associated with tissue ReGeneraTing Agent (RGTA) drops for the treatment of noninfectious corneal ulcers. RGTA treatment was applied (one drop every two days); however, if ulcer closure was not achieved, PRGF eye drops treatment was added (four times/day). The time taken to reach the ulcer closure, the Best Corrected Visual Acuity (BCVA), intraocular pressure (IOP), Visual Analog Scale (VAS, in terms of frequency and severity of symptoms), and Ocular Surface Disease Index (OSDI) were evaluated. Seventy-four patients (79 eyes) were included, and the mean age was 56.8 ± 17.3 years. The neurotrophic corneal ulcer was the most frequent disorder (n = 27, 34.2%), mainly for herpes virus (n = 15, 19.0%). The time of PRGF eye drops treatment associated with the RGTA matrix was 4.2 ± 2.2 (1.5-9.0) months, and the follow-up period was 44.9 ± 31.5 months. The ulcer closure was achieved in 76 eyes (96.2%). BCVA, VAS and OSDI improved from the baseline (p < 0.001), and IOP remained unchanged (p = 0.665). RGTA and PRGF in noninfectious ulcers were effective and could be a therapeutic alternative for this type of corneal disease.

Plasma rich in growth factors versus Mitomycin C in photorefractive keratectomy.

ABSTRACT: To evaluate the efficacy and safety of plasma rich in growth factors (PRGF) in photorefractive keratectomy (PRK) versus Mitomycin C (MMC).This is a comparative, longitudinal and retrospective case-control study (MMC vs PRGF), in patients with a spherical correction from -0.25 to -8.00 D and cylinder correction from -0.25 to -3.00. The uncorrected distance visual acuity (UDVA), refractive efficacy and safety indices, and changes in endothelial cell density were evaluated. The predictability was assessed with the postoperative manifest spherical equivalent.Forty-four patients (72 eyes) were treated with MMC and twenty-five patients (45 eyes) with PRGF. The final UDVA (LogMar) in MMC was 0.029 ±â€Š0.065 and in PRGF it was 0.028 ±â€Š0.048 (p = 0.383). The efficacy index for MMC was 0.98 ±â€Š0.10 and 1.10 ±â€Š0.46 for patients treated with PRGF (p = 0.062). The safety index for MMC was 1.03 ±â€Š0.11 and 1.12 ±â€Š0.46 (p = 0.158) for PRGF group. The change percentage of endothelial cell density was 0.9 ±â€Š11.6 for MMC and 4.3 ±â€Š13.1 for PRGF (p = 0.593). The predictability for MMC was 92.1% and for the PRGF was 91.9% (p = 0.976). Hyperemia, eye pain and superficial keratitis were observed in 11.1% of the MMC group; no adverse events were observed with the PRGF.The use of PRGF in PRK surgery is as effective as MMC. The PRGF shows a better safety profile than MMC for its intraoperative use in PRK.

Development of an in-house reconstructed human epidermis model as an alternative method in skin corrosion assessment.

Defining the corrosive properties of chemical products generally involves the use of animal models for human health safety assessment. However, a few alternatives to animal experimentation are currently internationally accepted in order to reduce animal suffering. One of these alternatives makes use of in vitro reconstructed human epidermis (RhE) models and predicts corrosive potential based on the evaluation of cell viability after topical exposure. These models rely on its similarity to human skin, both functional and histological, and are currently worldwide marketed by a few private companies. In this manuscript, we describe the fundamentals of the production of a Do It Yourself (DIY) RhE model, and the operating procedures for the assessment of skin corrosion based on the guidelines proposed for the development of new alternative methods for skin corrosion. Our results indicate that the DIY-RhE model resembles the anatomy of the normal human epidermis as seen by immunohistochemical analysis. Moreover, barrier properties of DIY-RhE were assessed by the measure of Transepithelial Electrical Resistance. Applicability of DIY-RhE for the assessment of skin corrosion was evaluated by measuring cell viability after topical exposure of twelve reference chemicals for 3 and 60 min. Predictive performance resulted in 100% sensitivity, 100% specificity and 100% accuracy matching current requirements for new RhE models proposed for the discrimination of corrosives and non-corrosives.

Los cambios estructurales de la retina, ¿nuevos biomarcadores de los trastornos mentales? Una revisión sistemática y síntesis temática de la literatura / Could structural changes in the retinal layers be a new biomarker of mental disorders? A systematic review and thematic synthesis

Recientemente se ha planteado que las alteraciones de las capas de la retina podrían ser un biomarcador de determinados trastornos mentales, al derivar esta de la misma capa embrionaria que el cerebro y estar conectada con este a través del nervio óptico. El objeto del presente artículo es ofrecer una revisión sistemática de la literatura y una síntesis temática sobre el estado actual de las alteraciones de las capas de la retina identificadas mediante tomografía de coherencia óptica en los pacientes con esquizofrenia, trastorno bipolar y depresión mayor. Para ello se realizó una búsqueda sistemática de la literatura, la lectura crítica de los artículos seleccionados y la síntesis temática de los resultados. Los pacientes con esquizofrenia son los que presentan más alteraciones, seguidos de los pacientes con trastorno bipolar, siendo muy escasos los hallazgos en la depresión. La capa de fibras nerviosas de la retina es la capa retiniana con más alteraciones en la esquizofrenia y en el trastorno bipolar, mientras que ningún estudio en depresión mayor encontró alteraciones en ella. De los parámetros clínicos, la duración de la enfermedad correlaciona significativa e inversamente con el grosor de las distintas capas en todos los trastornos. A la hora de interpretar estos datos es necesario tener en cuenta las limitaciones y diferencias de los estudios, especialmente el tiempo medio de evolución de los trastornos. Dado que este era muy diferente entre los 3 trastornos (más del doble en el caso de la esquizofrenia respecto a la depresión mayor), las diferencias en los resultados encontrados podrían deberse más al efecto del tiempo de evolución que al trastorno en sí. En conclusión, los hallazgos de la tomografía de coherencia óptica son esperanzadores, ya que podrían proporcionar biomarcadores de la neurodegeneración y/o neuroprogresión tanto de la esquizofrenia como del trastorno bipolar

It has recently been suggested that alterations of the layers of the retina could be a biomarker of specific mental disorders since they originate in the same embryonic layer as the brain and both are interconnected through the optic nerve. The purpose of this article is to offer a systematic review of the literature and a thematic synthesis on the current state of the alterations of the retina layers identified by optical coherence tomography in patients with schizophrenia, bipolar disorder and major depression. For this purpose, we performed a bibliographic search, a systematic review of the studies and a thematic synthesis of the reported findings. Patients with schizophrenia have more abnormal findings followed by patients with bipolar disorder, with very few findings in depression. The nerve fiber layer is the retinal layer with more abnormal findings both in schizophrenia and in bipolar disorder, while no study in major depression found alterations in it. Of the clinical parameters, the duration of the illness correlates significantly and inversely with the thickness of the different layers in all disorders. When interpreting these data, it is necessary to take into account the limitations and differences of the studies, especially the mean length of the disorders. Given that this was very different among the 3 disorders (more than doubled in the case of schizophrenia respect to major depression), the differences in the results found could be due more to the effect of the length of illness than to the disorder itself. In summary, optical coherence tomography findings are promising, since they could provide biomarkers of neurodegeneration and/or neuroprogression of both schizophrenia and bipolar disorder

QobuR - A new in vitro human corneal epithelial model for preclinical drug screening.

A new in vitro human corneal epithelial model (QobuR) obtained from normal limbal tissue has been developed to study ocular irritancy of different ophthalmic compounded drugs. Phenotypical characterization and trans-epithelial electrical resistance (TEER) of QobuR revealed essential similarities compared with a native human cornea, displaying functional markers and TEER values near 1500 Ωcm2 at day 7th of cellular differentiation. Using this model, ocular irritancy and barrier integrity alterations were evaluated using MTT reaction and variations in TEER. We found that some of the Non-Irritant products evaluated still damage the corneal epithelial integrity and current protocols for ocular irritancy should therefore include a barrier integrity evaluation. Moreover, in order to comprehensively evaluate corneal permeability of the active ingredients, we propose the use of QobuR as an all-in-one alternative method for evaluating ocular irritancy, barrier disruptions and permeability rates of topically applied ocular drugs to improve current in vitro drug testing procedures.

Could structural changes in the retinal layers be a new biomarker of mental disorders? A systematic review and thematic synthesis. / Los cambios estructurales de la retina, ¿nuevos biomarcadores de los trastornos mentales? Una revisión sistemática y síntesis temática de la literatura.

It has recently been suggested that alterations of the layers of the retina could be a biomarker of specific mental disorders since they originate in the same embryonic layer as the brain and both are interconnected through the optic nerve. The purpose of this article is to offer a systematic review of the literature and a thematic synthesis on the current state of the alterations of the retina layers identified by optical coherence tomography in patients with schizophrenia, bipolar disorder and major depression. For this purpose, we performed a bibliographic search, a systematic review of the studies and a thematic synthesis of the reported findings. Patients with schizophrenia have more abnormal findings followed by patients with bipolar disorder, with very few findings in depression. The nerve fiber layer is the retinal layer with more abnormal findings both in schizophrenia and in bipolar disorder, while no study in major depression found alterations in it. Of the clinical parameters, the duration of the illness correlates significantly and inversely with the thickness of the different layers in all disorders. When interpreting these data, it is necessary to take into account the limitations and differences of the studies, especially the mean length of the disorders. Given that this was very different among the 3 disorders (more than doubled in the case of schizophrenia respect to major depression), the differences in the results found could be due more to the effect of the length of illness than to the disorder itself. In summary, optical coherence tomography findings are promising, since they could provide biomarkers of neurodegeneration and/or neuroprogression of both schizophrenia and bipolar disorder.

Different Use of Cell Surface Glycosaminoglycans As Adherence Receptors to Corneal Cells by Gram Positive and Gram Negative Pathogens.

The epithelium of the cornea is continuously exposed to pathogens, and adhesion to epithelial cells is regarded as an essential first step in bacterial pathogenesis. In this article, the involvement of glycosaminoglycans in the adhesion of various pathogenic bacteria to corneal epithelial cells is analyzed. All microorganisms use glycosaminoglycans as receptors, but arranged in different patterns depending on the Gram-type of the bacterium. The heparan sulfate chains of syndecans are the main receptors, though other molecular species also seem to be involved, particularly in Gram-negative bacteria. Adherence is inhibited differentially by peptides, including heparin binding sequences, indicating the participation of various groups of Gram-positive, and -negative adhesins. The length of the saccharides produces a major effect, and low molecular weight chains inhibit the binding of Gram-negative microorganisms but increase the adherence of Gram-positives. Pathogen adhesion appears to occur preferentially through sulfated domains, and is very dependent on N- and 6-O-sulfation of the glucosamine residue and, to a lesser extent, 2-O sulfation of uronic acid. These data show the differential use of corneal receptors, which could facilitate the development of new anti-infective strategies.

Human Bone Derived Collagen for the Development of an Artificial Corneal Endothelial Graft. In Vivo Results in a Rabbit Model.

Corneal keratoplasty (penetrating or lamellar) using cadaveric human tissue, is nowadays the main treatment for corneal endotelial dysfunctions. However, there is a worldwide shortage of donor corneas available for transplantation and about 53% of the world's population have no access to corneal transplantation. Generating a complete cornea by tissue engineering is still a tough goal, but an endothelial lamellar graft might be an easier task. In this study, we developed a tissue engineered corneal endothelium by culturing human corneal endothelial cells on a human purified type I collagen membrane. Human corneal endothelial cells were cultured from corneal rims after corneal penetrating keratoplasty and type I collagen was isolated from remnant cancellous bone chips. Isolated type I collagen was analyzed by western blot, liquid chromatography -mass spectrometry and quantified using the exponentially modified protein abundance index. Later on, collagen solution was casted at room temperature obtaining an optically transparent and mechanically manageable membrane that supports the growth of human and rabbit corneal endothelial cells which expressed characteristic markers of corneal endothelium: zonula ocluddens-1 and Na+/K+ ATPase. To evaluate the therapeutic efficiency of our artificial endothelial grafts, human purified type I collagen membranes cultured with rabbit corneal endothelial cells were transplanted in New Zealand white rabbits that were kept under a minimal immunosuppression regimen. Transplanted corneas maintained transparency for as long as 6 weeks without obvious edema or immune rejection and maintaining the same endothelial markers that in a healthy cornea. In conclusion, it is possible to develop an artificial human corneal endothelial graft using remnant tissues that are not employed in transplant procedures. This artificial endothelial graft can restore the integrality of corneal endothelium in an experimental model of endothelial dysfunction. This strategy could supply extra endothelial tissue and compensate the deficit of cadaveric grafts for corneal endothelial transplantation.

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

PURPOSE: To evaluate refractive and visual outcomes and complications associated with phakic intraocular lens (pIOL) implantation to correct high myopia. SETTINGS: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Retrospective observational case series. METHODS: Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), refraction, vault, and adverse effects were evaluated after 5 years with Visian ICMV4 pIOL. RESULTS: Mean spherical equivalent (SE) dropped from -18.32 ± 2.37 diopters (D) preoperatively to -0.88 ± 0.52D 5 years postoperatively; 61% of eyes were within ±0.75 D of the target. The mean Snellen decimal CDVA and UDVA were 0.73 ± 0.23 and 0.55 ± 0.26, respectively. More than 50% of eyes achieved 20/25 or better CDVA postoperatively. Four eyes had lost 2 or 1 lines of CDVA, 10 eyes had not lost any lines from preoperatively, and 46 eyes had gained 1 or more lines of CDVA 5 years postoperatively. The safety index was 1.26 ± 0.32. Forty eyes had UDVA of 20/40 or better postoperatively. The efficacy index was 0.99 ± 0.42. At 5-year follow-up, the mean central vault was 475.28 ± 216.38 µm. No eyes showed central contact between the pIOL and crystalline lens. Nevertheless, 10 eyes showed peripheral contact with a central vault between 150 and 260 µm. Two eyes developed anterior subcapsular cataract, although only 1 eye required cataract surgery. CONCLUSIONS: Predictability, safety and effective outcomes of posterior pIOL of (- were good, as well as postoperative complications over the long term. A central vault of 260 µm was enough to prevent the peripheral contact between the pIOL and crystalline lens in eyes with high myopia. FINANCIAL DISCLOSURE: The authors have no proprietary interest in any of the materials mentioned in this article.

Collagen copolymer posterior chamber phakic intraocular lens for hyperopia correction: three-year follow-up.

PURPOSE: To assess the efficacy, predictability, safety, and stability of the Visian V3 Implantable Collamer Lens posterior chamber phakic intraocular lens (PC pIOL) for moderate to high hyperopia. SETTING: Private clinic, Oviedo, Spain. DESIGN: Prospective nonrandomized clinical study. METHODS: The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction, endothelial cell density, intraocular pressure (IOP), central vault, and adverse events were evaluated for 3 years postoperatively. RESULTS: The study comprised 73 eyes of 44 patients. The mean spherical equivalent decreased from +4.84 diopters (D) ± 1.6 (SD) (range +1.00 to +7.75 D) preoperatively to -0.13 ± 0.39 D 3 years postoperatively; 61 eyes (83.6%) were within ±0.50 D of the target refraction and all eyes were within ±1.00 D. The mean postoperative Snellen decimal UDVA and CDVA was 0.86 ± 0.17 and 0.91 ± 0.16, respectively. Most eyes (91.8%) had no change from the preoperative CDVA or gained 1 or more lines. One eye (1.4%) lost 2 lines, and no eye lost more than 2 lines. Three years postoperatively, the efficacy index was 1.02 and the safety index was 1.08. The IOP remained stable over time, with no significant increase postoperatively. The mean endothelial cell loss was 4.7%, remaining unchanged over time. No postoperative complications or adverse events, including pupillary block or secondary cataract, occurred. CONCLUSIONS: Implantation of the PC pIOL was safe and effective in correcting hyperopic refractive errors, with stable visual and refractive outcomes. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Inferior intrastromal corneal ring segments in paracentral keratoconus with no coincident topographic and coma axis.

PURPOSE: To assess the visual and refractive outcomes of implantation of intrastromal corneal ring segments (ICRS) in keratoconic eyes with no coincident topographic and comatic axes. METHODS: Forty-one keratoconic eyes of 39 patients with no coincident topographic and comatic axes were implanted inferiorly with a Ferrara-type ICRS (Keraring SI6; Mediphacos Inc., Belo Horizonte, Brazil) of 150° of arc with a thickness of 150, 200, and 250 µm. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), corneal coma-like root mean square, and residual refractive errors analyzed using vector analysis were recorded before and 6 months after the ICRS implantation. RESULTS: Mean UDVA was 0.76 ± 0.41 logMAR before and 0.53 ± 0.46 logMAR after surgery (P = .0006). CDVA was 0.13 ± 0.14 logMAR before and 0.07 ± 0.09 logMAR after surgery (P = .0007). Two eyes (4.9%) lost two lines or more of CDVA, 3 eyes (7.32%) lost one line, 16 eyes (39.02%) had no change in CDVA, 9 eyes (21.95%) gained one line, and 11 eyes (26.83%) gained two lines or more of CDVA. The safety index was 1.10. Spherical equivalent was significantly reduced after ICRS implantation (P < .001). Corneal coma-like root mean square changed from 0.80 ± 0.53 µm before surgery to 0.61 ± 0.59 µm after surgery (P = .02) for 4.5 mm of pupil size. CONCLUSIONS: One Ferrara-type ICRS of 150° of arc with a thickness of 150, 200, or 250 µm implanted inferiorly may reduce both astigmatism and corneal coma-like aberrations in keratoconic eyes with no coincident topographic and comatic axes, providing an improvement of UDVA and CDVA values.

Visual quality after diffractive intraocular lens implantation in eyes with previous hyperopic laser in situ keratomileusis.

PURPOSE: To evaluate distance, intermediate, and near visual quality in eyes with diffractive intraocular lens (IOL) implantation after previous hyperopic laser in situ keratomileusis (LASIK). SETTING: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Cohort study. METHODS: Corrected distance visual acuity (CDVA) at 12.5%, 25.0%, and 100% contrast levels under photopic and mesopic conditions; uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuity, defocus curves, and corneal higher-order aberrations (HOAs) were measured in eyes that had AcrySof Restor SN60D3 spherical IOL implantation (study group) and in phakic eyes (control group) after hyperopic LASIK. RESULTS: Under photopic conditions at 100% contrast, there were no statistically significant differences between the 2 groups (P > .01) and the CDVA was 0.1 logMAR or better (approximately 20/25) in both groups. At 25.0% and 12.5% contrast, there were no statistically significant differences between the 2 groups (P > .01). Under mesopic conditions, the control group had better CDVA than the study group without glare at all contrasts (P < .01). In the study group, the mean UNVA was 0.017 logMAR ± 0.030 (SD) (approximately 20/20) and the mean DCNVA, 0.009 ± 0.030 logMAR. There was statistically significant worsening of visual acuity as a function of the distance to the test (P < .01). There were no statistically significant differences in HOAs between the 2 groups (P > .01). CONCLUSIONS: In eyes with previous hyperopic LASIK, the diffractive IOL provided good visual quality at distance, comparable to that obtained in phakic eyes under photopic conditions, although visual performance was slightly poorer under mesopic conditions. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Posterior chamber collagen copolymer phakic intraocular lenses to correct myopia: five-year follow-up.

PURPOSE: To evaluate the long-term safety and efficacy of posterior chamber collagen copolymer phakic intraocular lens (pIOL) implantation to correct myopia. SETTING: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Cohort study. METHODS: Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, pIOL vault, endothelial cell loss, and adverse events were evaluated for 5 years after implantation of the Visian Implantable Collamer Lens pIOL for moderate to high myopia. RESULTS: The mean spherical equivalent (188 eyes) decreased from -11.17 diopters (D) ± 3.40 (SD) preoperatively to -0.88 ± 0.72 D 5 years postoperatively. The mean change in refraction from 1 month to 5 years was -0.65 ± 0.65 D. The mean UDVA and CDVA (Snellen decimal) were 0.69 ± 0.26 and 0.83 ± 0.15, respectively. The mean safety and efficacy indices were 1.27 ± 0.33 and 0.89 ± 0.35, respectively. No eye lost more than 2 lines of visual acuity; 70% achieved 0.80 or better CDVA. Three eyes (1.6%) developed late anterior subcapsular cataract that was clinically significant in 1 case, leading to pIOL removal and phacoemulsification. Of the 3 eyes (1.6%) with a mild transient increase in intraocular pressure (up to 27 mm Hg), none required a second surgical procedure or prolonged topical medication. The total endothelial cell loss (considered cumulatively at consecutive intervals through 5 years) was 7.7%. There was a tendency toward decreased pIOL vault decrease over time. No vision-threatening complications occurred. CONCLUSION: Implantation of the collagen copolymer pIOL for moderate to high myopia was safe and effective and provided long-term predictable, stable refractive results.

Refractive lens exchange with Acri.LISA bifocal intraocular lens implantation.

PURPOSE: To assess efficacy, safety, and predictability after refractive lens exchange (RLE) in patients who had bilateral implantation of an Acri.LISA 366D diffractive bifocal intraocular lens (IOL). METHODS: Sixty-six eyes of 33 consecutive patients were examined after RLE who had bilateral implantation of an Acri.LISA bifocal 366D IOL. Eyes were divided into myopic and hyperopic groups. Monocular uncorrected distance visual acuity, best-corrected distance visual acuity (BCVA), uncorrected distance near visual acuity, and best distance-corrected near visual acuity (BCNVA) were recorded preoperatively and 6 months after surgery. RESULTS: Efficacy indexes were 0.73 for myopic and 0.85 for hyperopic eyes at 6 months postoperatively. For the myopic group, 2 eyes lost 1 line, 4 eyes gained 1 line, and 6 eyes gained ≥2 lines; for the hyperopic group, 11 eyes lost 1 line, 8 eyes gained 1 line, and 7 eyes gained 2 lines. Safety indexes were 1.07 and 1.03 for myopic and hyperopic eyes, respectively. Safety indexes at near were 1.03 for myopic and 1.00 for hyperopic eyes. Efficacy indexes at near were 1.00 for myopic and 0.99 for hyperopic eyes. CONCLUSIONS: Bilateral implantation of an Acri.LISA 366D bifocal IOL after RLE is an effective procedure for correcting ametropia and presbyopia.

Collagen copolymer toric posterior chamber phakic intraocular lenses to correct high myopic astigmatism.

PURPOSE: To assess the safety, efficacy, stability, and predictability after implantation of a toric intraocular copolymer (Collamer) lens (pIOL) to correct high myopic astigmatism. SETTING: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. METHODS: This study evaluated eyes that had implantation of a toric pIOL. Outcome measures were the uncorrected (UDVA) and corrected (CDVA) distance visual acuities (Snellen decimal), refraction, and postoperative complications. RESULTS: The study included 15 eyes of 12 patients (9 women). Preoperatively, the mean manifest spherical refraction was -1.98 diopters (D) +/- 1.32 (SD) (range -0.50 to -5.50 D) and the mean refractive cylinder, -4.85 +/- 0.83 D (range -6.50 to -4.00 D). At 12 months, the mean refractive cylinder was -0.55 +/- 0.52 D (range -1.50 to 0.00 D), with 93.3% of eyes having less than 1.00 D of cylinder. The mean spherical equivalent was -0.31 +/- 0.42 (range -1.00 to 0.75 D), with more than 70% of eyes within +/-0.50 D of the target. For the astigmatic components, 93.3% of eyes were within +/-1.00 D of J0 (r(2) = 0.98) and all eyes were within +/-1.00 D of J45 (r(2) = 0.98). The mean UDVA was 0.70 +/- 0.20 and the mean CDVA, 0.83 +/- 0.12. The overall efficacy index was 0.90. Postoperatively, all eyes had unchanged CDVA or gained 1 or more lines. CONCLUSION: The refractive outcomes and improvement in UDVA and CDVA were rapidly achieved and remained fairly consistent throughout the follow-up period, supporting the use of toric pIOLs in eyes with high astigmatism. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.