El glistening de las lentes intraoculares: revisión de la literatura / Glistening on intraocular lenses: a review

El glistening en las lentes intraoculares (LIO) es un fenómeno en el que se forman diminutas microvacuolas llenas de agua dentro del material de la LIO, lo que hace que la luz se disperse y cree un efecto centelleante o reluciente. La presencia del glistening es frecuente en muchos tipos de materiales y modelos de LIO, y se ha estudiado ampliamente en los últimos años para conocer su incidencia, factores de riesgo, evolución y posible relevancia clínica. Clásicamente se ha estudiado in vitro en laboratorio o mediante fotografía obtenida con lámpara de hendidura. Sin embargo, son técnicas que requieren de un explorador experto, además de requerir mucho tiempo y un complejo procesado de las imágenes. En los últimos años, han surgido propuestas basadas en la cámara de Scheimpflug y en la tomografía de coherencia óptica como forma de simplificar el análisis del glistening en las LIO. Se ha descrito que tanto el proceso de fabricación, como el propio material acrílico hidrofóbico, y el tiempo desde la cirugía son factores de riesgo relacionados con la aparición de glistening. Además, aún se desconocen numerosas cuestiones relacionadas con este fenómeno, como la cantidad de puntos o el tamaño de los mismos necesarios para causar afectación de la función visual, ya que se han descrito diferentes fenómenos ópticos relacionados con el glistening de las LIO (AU)

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs (AU)

Glistening on intraocular lenses: A review.

The glistening in intraocular lenses (IOLs) is a phenomenon in which tiny water-filled microvacuoles (MVs) form within the IOL material, causing light to scatter and create a sparkling or shimmering effect. The presence of glistening is common in many types of IOL materials and models and has been extensively studied in recent years to determine its incidence, risk factors, evolution, and possible clinical relevance. Classically, it has been studied in vitro in the laboratory or by means of photography obtained with a slit lamp, but these were techniques that required either specific technology or an expert explorer, complex image processing, and required a lot of time. In recent years, proposals based on the Scheimpflug camera and optical coherence tomography have emerged to try to simplify the analysis of glistening in IOLs. It has been described that the manufacturing process, the hydrophobic acrylic material, or the time since surgery are risk factors for the appearance of glistening. In addition, many issues related to this phenomenon are still unknown, such as not knowing from what number of points or their size they may have relevance to visual function since different optical phenomena related to glistening have been described on the IOLs.

Objective Classification of Glistening in Implanted Intraocular Lenses Using Optical Coherence Tomography: Proposal for a New Classification and Grading System.

PURPOSE: To propose a classification of the glistening in intraocular lenses (IOL) using swept-source optical coherence tomography (SS-OCT) by means of a simple, objective and reproducible method that allows the quantification of the presence and severity of glistening. METHODS: A cross-sectional study on a sample of 150 eyes of 150 patients who underwent cataract surgery in at least 600 days before the exam and attended a routine examination. Each subject was examined by SS-OCT after pupil dilation, identifying the presence of glistening or hyperreflective foci (HRF) in the central area of the IOL. The degree of glistening was classified into four categories: 0: ≤5 HRF; 1: 6 to 15 HRF; 2: 16 to 30 HRF; and 3: >30 HRF. The intra and interobserver reproducibility (intraclass correlation coefficient, ICC) in the quantification and classification of the glistening were calculated. The correlation between the horizontal and vertical scan of the IOL was also assessed. RESULTS: Glistening was present in the IOL in 42.7% of the patients. The mean number of HRF or glistening microvacuoles was 10.4 ± 26.2 (range 0 to 239). In total, 63.3% of the IOLs had a grade 0, 20% grade a 1, 6.7% grade a 2 and 10% a grade 3. The intraobserver and interobserver reproducibility were very high, both for the absolute quantification of the glistening (ICC ≥ 0.994) and for the severity scale (ICC ≥ 0.967). There was an excellent correlation in the quantification of the IOL glistening between the horizontal and vertical scans (R ≥ 0.834; p < 0.001). CONCLUSIONS: The use of SS-OCT makes it possible to identify, quantify and classify IOL glistening in a simple, objective and reproducible way. This technique could provide relevant information for the study of the glistening on IOLs.

Long Term Clinical Outcomes of Hydrophilic and Hydrophobic Versions of a Trifocal IOL with the Same Optical Design.

Purpose: To show the visual and refractive outcomes in Asian eyes with cataract when bilaterally implanted with either a hydrophobic FineVision POD F GF or a hydrophilic FineVision POD F intraocular lens (IOL). Methods: Forty-six patients were randomized to receive POD F GF or POD F IOLs. Visual and refractive outcomes were assessed up to 24 months post-surgery. Measurements included uncorrected-distance visual acuity, corrected-distance visual acuity (CDVA), distance-corrected intermediate visual acuity (DCIVA), distance-corrected near visual acuity (DCNVA), refraction, defocus curve, photopic and mesopic contrast sensitivity, and patient-reported outcomes. Results: Mean spherical equivalent was close to emmetropia for both groups and stable across postoperative visits. Overall, 97.73% and 100% of eyes in the POD F GF IOL group and 95.65% and 100%, of eyes in the POD F IOL group were within ±1.00D of the target refraction at 12 and 24 months, respectively. All patients showed a CDVA of ≥20/25 at 12- and 24-months post-surgery. In both groups, 24 months post-surgery 91% of patients presented a DCIVA of ≥20/25 and 83.3% of patients had a DCNVA of ≥20/25. Defocus curve showed continuous visual acuity, being 20/32 or better in both groups over a 4.00D range between 1.00D and -3.00/-3.50D. Both groups showed good contrast sensitivity values for photopic and mesopic conditions. Overall, 86.4%, 86.4%, and 72.7% of patients implanted with the POD F GF IOL reported not wearing glasses at all for distance, intermediate, and near vision, respectively. These values were 81.8%, 86.4%, and 90.9% for patients implanted with the POD F IOL. Both groups of patients reported similar satisfaction percentages (100% very satisfied/satisfied) and would recommend the procedure (100% definitively yes/probably yes). Conclusion: This study demonstrates good visual and refractive outcomes for both the FineVision POD F GF and the FineVision POD F IOLs when implanted in Asian eyes.

Raman Spectroscopy of six explanted acrylic hydrophobic foldable intraocular lenses with glistening.

Purpose: To study and interpret Raman spectra of six explanted acrylic hydrophobic foldable intraocular lenses (HFIOLs) with grade six microvacuoles and to understand the possible mechanism for microvacuole formation. Methods: Clinical data, slit-lamp photographs, and optical microphotographs of the explanted analytes were obtained. RS of the analytes were registered using a confocal Raman microscope (Lab RAM HR Evolution, Horiba Jobin Yvon) and Horiba Lab Space 6 Spectroscopy Suite software. Data were interpreted by identifying the functional group and fingerprint region of the spectra about the available literature. Results: IOLs were explanted for visual impairment after an average interval of 11.2 years following implantation. Each of the HFIOLs exhibited distinctive and identical Raman bands at the frequency range of 200-1,800, 2,600-3,000, and 3,200-3,700 cm-1 which were identified with those reported in the literature. The unique bands and peaks of the spectra were specific to the functional groups, its ring and other stretching variations, hydroxyl group, and water molecule. A spike at 1,640 cm-1 revealed the presence of monomer and indicated material bioincompatibility of the samples. Conclusion: Raman spectroscopy (RS) was found specific and an effective tool to detect the material change in the HFIOL and constituents of polymer biomaterial about microvacuole formation and also suggested modification and development of a more biocompatible and non-biodegradable polymer blend where RS could be a monitoring tool.

[Safety and efficacy of A1-UV aspheric intraocular lens implantation over the postoperative 5 years].

Objective: To evaluate the clinical safety and efficacy of A1-UV aspheric intraocular lens (IOL) implantation over the postoperative 5 years. Methods: Prospective cohort study. The subjects came from a finished multicenter, randomized and controlled clinical trial with a follow-up period of 1 year from April to November 2012. The clinical research centers were Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Peking University Third Hospital, Tianjin Medical University Eye Hospital, and Daping Hospital of Army Medical University. Cataract patients in the experimental group were implanted with A1-UV type IOL, while cataract patients in the control group were implanted with SN60WF type IOL, and monocular patients were enrolled. From April to May 2018, patients enrolled in the previous study were recalled for follow-up and continued observation. The visual acuity, spherical equivalent, postoperative complications, non-contact intraocular pressure and subjective evaluation results were statistically analyzed preoperatively, at 1 to 2 days, 1 week, 1 month, 3 months, 6 months, 1 year and 5 years after operation. The main statistical methods included Mann Whitney U test, Wilcoxon signed rank test, independent sample t test, chi square test and Fisher exact test. Results: A total of 42 subjects (22 in the experimental group and 20 in the control group) completed 5-year continuous observation. Among the 42 subjects, 28 were female and 14 were male. The age was (70±9) years, and the time from surgery to recall was (5.77±0.19) years. The age, gender distribution, left/right eye distribution, axial length, IOL power and nucleus hardness classification data of the experimental group and the control group were balanced and comparable (all P>0.05). At different visiting time points, there was no significant difference in the best corrected distance visual acuity (BCDVA), best corrected near visual acuity (BCNVA), uncorrected distance visual acuity (UCDVA) and uncorrected near visual acuity (UCNVA) between the groups (all P>0.05). At 5 years after operation, the UCDVA, BCDVA and BCNVA of the two groups were significantly improved compared with the baseline [all P<0.01; UCDVA was improved from 0.75 (0.30 to 1.30) to 0.10 (-0.10 to 0.70) in the experimental group and from 0.75 (0.30 to 1.60) to 0.20 (-0.10 to 0.80) in the control group; BCDVA was from 0.60 (0.10 to 1.00) to 0.00 (-0.10 to 0.54) in the experimental group and from 0.60 (0.10 to 1.60) to 0.10 (-0.10 to 0.50) in the control group; BCNVA was from 0.55 (0.00 to 1.10) to 0.10 (-0.10 to 0.60) in the experimental group and from 0.55 (0.10 to 1.60) to 0.10 (-0.20 to 0.60) in the control group], but there was no significant change in the UCNVA (both P>0.05). There were no significant differences in the spherical equivalent, intraocular pressure, subjective evaluation of visual adverse symptoms, distance vision spectacle independence and comprehensive evaluation of satisfaction between the groups (all P>0.05). In the experimental group, one eye (4.5%) had an abnormal pupil, one eye (4.5%) had an abnormal IOL with a few particles on the surface of the IOL but no glistening, and 3 eyes (13.6%) had posterior capsular opacification (PCO); in the control group, one eye (5.0%) had an abnormal cornea, five eyes (25.0%) had abnormal IOLs [one eye (5.0%) had IOL calcification, and four eyes (20.0%) had IOL glistening], and one eye (5.0%) had PCO with posterior capsular folds and IOL tilt. There was no significant difference in PCO and IOL abnormality between the two groups (both P>0.05), but there was significant difference in the occurrence of IOL glistening (P=0.04). Conclusion: The long-term effect of A1-UV aspheric IOL on improving the UCDVA is stable and good, with high subjective satisfaction of patients, a low incidence of PCO, no glistening and good biocompatibility, over the postoperative 5 years. (Chin J Ophthalmol, 2021, 57: 41-47).

A narrative review of intraocular lens opacifications: update 2020.

The opacifications of intraocular lenses (IOLs) can significantly impact patients visual quality. Despite the identification of specific risk factors, manufacturing changes, opacifications are not eliminated. Likewise, more attention in recent studies was paid to possible new risk factors, however one of the most important purposes of the studies remains opacifications effect on visual performance, which could be disturbed in different aspects. The aim of this review is to discuss the main risk factors of IOLs opacification in particular IOL types, and its impact on vision quality. Different risk factors were discussed in the study, including the material of IOLs, the impact of the breakdown of blood-aqueous barrier (BAB), and certain surgeries that can be associated with opacification formation. Glistenings occur more often in a hydrophobic material, however, the changes in water content of the IOLs can significantly reduce the formation of glistenings. The studies showed a significant effect of intraocular injection of exogenous air or gas during Descemet-stripping endothelial keratoplasty, Descemet-stripping automated endothelial keratoplasty, Descemet membrane endothelial keratoplasty, and pars plana vitrectomy on calcification formation. It raises a concern, as the incidence of these surgeries is increasing. Visual acuity decreases significantly after the calcification in IOLs occurs, and it usually causes IOLs exchange. However, disability glare seems to be more affected in patients with IOLs, which were affected by glistenings than visual acuity. Disability glare is associated with increased levels of straylight, which was widely evaluated in recent studies and it was reported to be a susceptible measurement to detect the presence of IOLs pathology. For future researches, it should be noticed that disability glare and straylight are more appropriate in evaluating IOLs opacification effect on visual quality than visual acuity. While reviewing the main risk factors of IOLs opacifications particular attention must be paid on calcification occurrence in hydrophilic acrylic IOLs after surgeries with intraocular injection of exogenous air or gas.

Comparison of Visual Performance and Patient Satisfaction Outcomes with Two Trifocal IOLs with Similar Optical Design but Different Materials.

PURPOSE: To compare clinical outcomes in a prospective trial of cataract surgery patients bilaterally implanted with two different trifocal intraocular lenses (IOLs) with very similar optical designs but consisting of different IOL materials (hydrophobic and hydrophilic). PATIENTS AND METHODS: Fifty-one patients (102 eyes) were randomized to receive trifocal IOLs bilaterally - FineVision POD F (hydrophilic) or FineVision POD F GF (hydrophobic) (both PhysIOL, Liége, Belgium). The follow-up period was 3 months. Outcome measurements included uncorrected distance (UDVA), corrected distance (CDVA), distance-corrected intermediate (DCIVA), and distance-corrected near visual acuity (DCNVA), refraction, negative dysphotopsia, optical quality of vision, contrast sensitivity under photopic and mesopic conditions, halometry (discrimination index), and patient-reported outcomes. RESULTS: At the final study visit, mean (SD) values for binocular UDVA, CDVA, DCIVA (80 cm), and DCNVA (40 cm) were -0.01 (0.06), -0.04 (0.04), 0.09 (0.10), and 0.10 (0.09) logMAR, respectively, for POD F, and 0.01 (0.08), -0.03 (0.03), 0.08 (0.1), and 0.13 (0.11) respectively, for POD F GF. Defocus assessments showed a continuous curve with a functional range of visual acuity (≤0.15 logMAR) from ~30 cm to infinity in both groups. The discrimination index was >0.85 for all patients, and both groups showed similar contrast sensitivity under photopic and mesopic conditions. At 3 months, no patient reported negative dysphotopsia, and high satisfaction rates were observed. CONCLUSION: Clinical outcomes showed no significant difference between each lens when measured at 1 month and 3 months after implantation. This equally good clinical performance of hydrophilic and hydrophobic trifocal lenses allows the surgeon to choose the IOL material based on personal preferences or patients' needs.

Imaging of Muller cell sheen dystrophy.

To report a rare case of Muller cell sheen dystrophy and to describe its clinical and diagnostic aspects. A 42-year-old woman presented with unilateral defective vision. Fundus evaluation revealed bilateral glistening retinal reflexes throughout the posterior pole with a wrinkled appearance in the right. Spectral Domain-OCT in the right showed abnormal internal limiting membrane, intraretinal schisis with serous detachment at macula. Angiography revealed staining along vessels. Electroretinogram in the affected eye was negative. At 4 months of follow up, vision dropped and intraretinal schisis increased. Family screening was negative.

Sjogren-Larsson Syndrome: Mechanisms and Management.

Sjogren Larsson syndrome (SLS) is a rare autosomal recessive inborn error of lipid metabolism due to mutations in the ALDH3A2 that result in a deficiency of fatty aldehyde dehydrogenase (FALDH). The syndrome has a high prevalence in Sweden where it was first described, but now known to occur worldwide. The classical triad of ichthyosis, mental retardation and spasticity characterizes clinical features. Preterm birth is common. "Glistening white dots" in the retina is a pathognomic clinical feature. Magnetic resonance imaging of the brain demonstrates leukoencephalopathy predominant in the periventricular region. Cerebral MR spectroscopy reveals a characteristic abnormal lipid peak at 1.3ppm and a small peak at 0.9ppm. The primary role of FALDH is oxidation of medium and long-chain aliphatic aldehydes derived from fatty alcohol, phytanic acid, ether glycerolipids and sphingolipids. The diagnosis is based on the typical phenotype, demonstration of the enzyme deficiency and presence of biallelic mutations in the ALDH3A2. The management of SLS largely remains symptomatic currently. However, several potential therapeutic options are being developed, keeping in view of the fundamental metabolic defects or correcting the genetic defect. This review aims to summarize the clinical, genetic and biochemical findings, pathogenetic mechanisms and the current therapeutic options, in SLS.

Incidence of posterior capsular opacification requiring Nd:YAG capsulotomy after cataract surgery and implantation of enVista® MX60 IOL.

PURPOSE: To evaluate incidence of posterior capsule opacification requiring Nd:YAG capsulotomy over 3 years in a large series of eyes implanted with the enVista® MX60 Intraocular Lens (IOL). METHODS: A university-based, single-center, observational study of patients' medical records was conducted. Uneventful cataract surgery patients with in-the-bag implantations of the enVista® MX60 IOL with a minimum of 24 months follow-up were included in the study. Exclusion criteria were insufficient follow-up (<24 months), intraoperative complications and combined surgery. The primary outcome measure was rate of YAG laser capsulotomy, while secondary outcome measures were time to YAG laser capsulotomy and rate of glistenings. RESULTS: A total of 245 eyes of 143 patients received the MX60 IOL and were followed in the same center. Of these, 226 eyes were included in the study. Mean age was 80.7±8.3 years and M/F ratio was 42/101 (29.4/70.6%). The mean preoperative distance (logMAR) visual acuity was 0.67±0.5, while postoperatively it was 0.31±0.5 and 0.32±0.5 at the last visit. The Mean±SD follow-up time (min-max) was 35.2±7.2, (24-48.4) months. The incidence of Nd:YAG capsulotomy over 3 years was 5/226 (2.2%). Average time between surgery and Nd:YAG capsulotomy was 32.17 months. Univariate analysis of age, gender, presence of comorbidity and baseline visual acuity found no predictive factors for capsulotomy. No glistenings were reported at any postoperative visit. CONCLUSION: The three-year cumulative incidence of PCO requiring Nd:YAG laser capsulotomy was 2.2% for the enVista® MX-60 IOL, with no glistenings observed during follow-up. This low rate confirms the excellent safety profile of this IOL.

[Posterior capsule opacification, glistenings and visual outcomes: 3 years after implantation of a new hydrophobic IOL]. / Performances visuelles, glistening et opacification capsulaire postérieure : 3 ans après l'implantation d'un nouvel implant hydrophobe.

PURPOSE: To evaluate the visual outcomes, the incidence of glistenings and posterior capsule opacification in a series of consecutive eyes with a new blue light-filtering hydrophobic acrylic intraocular lens (IOL) SETTING: Service d'ophtalmologie, clinique Beausoleil, avenue de Lodève, Montpellier. DESIGN: Retrospective, cross-sectional study. METHODS: This study included a series of 66 eyes that underwent routine cataract surgery with PODEye (PhysIOL SA, Liège, Belgium) monofocal IOL implantation between May 2011 and November 2011. These eyes were compared for glistenings with patients implanted with Acrysof material IOL (Alcon, Fort Worth, USA) who had a routine postoperative examination between January 2015 and August 2015. The safety of the IOL was assessed by visual acuity outcomes, as well as rotational stability, centration and postoperative medication. The incidence and severity of glistenings were evaluated with the slit lamp. Glistenings and PCO were graded subjectively (0=absent; 1=moderate; 2=dense). Follow-up was 3 years. RESULTS: The mean visual acuity after PODEye implantation was 0.98±0.05 (n=50) in decimal notation at 1 year, 0.98±0.06 at 1 week, (n=66), 1.00±0.01 at 3 weeks (n=64) and 0.99±0.02 at 3 months (n=59). The IOL displayed stable positioning in all axes. Glistenings of grade 2 were absent in the G-Free/PODEye group, whereas they were significantly present in the Acrysof group. One out of 43 eyes at 3-year follow-up underwent YAG capulotomy at 37 months. Sixty-six percent of eyes had no PCO (grade 0) at 3 years. CONCLUSIONS: The PODEye IOL was safe and stable. Glistenings grade 2 or more were not found with this blue light-filtering hydrophobic acrylic IOL. PCO occurrence was low at three years.

Influence of surface light scattering in hydrophobic acrylic intraocular lenses on laser beam transmittance.

The aim of this study was to experimentally examine the changes in the transmittances of photocoagulation lasers when surface light scattering increases in AcrySof intraocular lenses (IOLs). SA60AT IOLs (Alcon) were acceleratingly aging for 0, 3, 5, and 10 years to simulate surface light scattering, and the surface light-scattering intensities of both IOL surfaces were measured using a Scheimpflug photographer. The powers of laser beams that passed from a laser photocoagulator through the aged IOLs were measured at 532, 577, and 647 nm. Changes in the laser power and transmittance with the years of aging and the intensities of surface light scattering were examined. Although the intensity of surface light scattering increased with the years of aging, the laser power did not change with the years of aging (P > 0.30, Kruskal-Wallis test). There were no significant changes in the laser transmittance with the years of aging or the laser wavelength (P > 0.30 and 0.57, respectively). The intensity of surface light scattering revealed no significant association with the laser transmittance at any wavelength (P > 0.37, liner regression). The increases in the surface light scattering of the AcrySof IOLs would not influence retinal photocoagulation treatments for up to 10 years after implantation.

Intraindividual Comparison of Visual Outcomes between Blue Light-filtering and Ultraviolet Light-filtering Intraocular Lens

PURPOSE: To compare the clinical results of short-term visual acuity and quality of vision after implantation of a yellow-tinted blue light-filtering intraocular lens (IOL) (Acrysof IQ® SN60WF) and an clear ultraviolet (UV) light filtering IOL (enVista™ MX60) in the same patient. METHODS: 44 patients with bilateral cataract received an SN60WF in one eye and an MX60 in the other eye. All eyes were evaluated for refraction power and uncorrected visual acuity (UCVA) at preoperative and 1, 3 months postoperatively. At postoperative 3 months, corrected visual acuity, quality of vision (OQAS II®), contrast sensitivity (CGT 2000®) and visual field (Humphrey Field Analyzer®), and subjective patients' response to the degree of brightness were evaluated. Furthermore, glistening degree, intraocular stability, and posterior capsular opacification were examined. RESULTS: There were no significant differences in average refractive power or UCVA at 1 and 3 months (p > 0.05) between the two groups. At 3 months after cataract surgery, the quality of vision according to OQAS II®, the contrast sensitivity according to CGT 2000® with the glare either on or off, and visual field; showed no difference between the two groups (p > 0.05). Both IOLs had no glistening and posterior capsular opacity. The patients' response to the degree of brightness shows that MX60 (48.3%) has a higher degree of satisfaction. CONCLUSIONS: Yellow-tinted blue light-filtering IOL and clear UV light-filtering IOL had no difference in short-term visual acuity and quality of vision. Subjective brightness perception, however, was better with clear UV light-filtering IOL.

Sjogren-Larsson syndrome: A rare neurocutaneous disorder.

Sjogren-Larsson syndrome is an autosomal recessive disorder characterized by defective activity of fatty aldehyde dehydrogenase. It presents as a triad of congenital ichthyosis, spastic diplegia, and mental retardation. The pathology behind this syndrome is the failure of degradation of fatty aldehydes. This case is presented for its rarity.

Comparison of Clinical Long-Term Outcomes with Two Types of One-Piece Aspheric Intraocular Lenses after Cataract Surgery

PURPOSE: To compare the clinical outcomes of glistening-free intraocular lens (IOL) and conventional 1-piece aspheric IOL in implanted in-the-bag. METHODS: After phacoemulsification performed by a single surgeon, 2 different IOLs were implanted: enVista MX60 (glistening-free 1-piece aspheric IOL) in 38 eyes (group A) and AcrySof IQ (conventional 1-piece aspheric IOL) in 46 eyes (group B). Glare symptom score (0-5) obtained by questionnaires, best corrected visual acuity (BCVA), Functional Acuity Contrast Test (FACT), posterior capsular opacity (PCO), glistening formation and spherical equivalent error were compared and analyzed preoperatively and 6 months and 12 months postoperatively. RESULTS: A statistically significant improvement of BCVA and contrast sensitivity postoperatively was observed in all groups. There was statistically significant increase of glistening in group B compared with group A. However, there was no significant difference of FACT scores of spatial frequency in A, B, C, D and E columns and glare symptom score (0-10) obtained by questionnaires 12 months after surgery. Spherical equivalent errors were -0.38 +/- 0.27 D and -0.36 +/- 0.28 D for groups A and B, respectively. PCO occurred in 2 eyes in group A and 4 eyes in group B. CONCLUSIONS: EnVista MX60 IOL showed less glistening formation than AcrySof IQ IOL, however, there was no significant difference in terms of vision quality such as BCVA, FACT and glare symptom score at 12 months postoperatively.

Decreased visual acuity resulting from glistening and sub-surface nano-glistening formation in intraocular lenses: A retrospective analysis of 5 cases.

BACKGROUND: To report on five patients with decreased visual acuity due to glistening and severe sub-surface nano-glistening (SSNG) formation within their intraocular lenses (IOLs). DESIGN: Case reports and analysis of extracted IOLs. PARTICIPANTS AND SAMPLES: We report improved visual acuity when IOLs with severe glistening and SSNG were exchanged for clear IOLs in five patients. METHODS: Case reports. MAIN OUTCOME MEASURES: The main outcome measure was visual acuity. The secondary outcome measure was light transmission. Explanted IOLs were subjected to investigation. Pre- and postoperative slit lamp images of the anterior eye and microscopic images of the extracted IOLs were taken and compared. Light transmission of the IOL was measured using a double beam type spectrophotometer. An integrated value of the percentage light transmittance in the visible light spectrum was calculated. RESULTS: We report on five patients whose visual acuity improved when IOLs were exchanged because of severe glistening and SSNG. All of the affected IOLs were MA60BM (Alcon, Forth Wroth Texas, USA) and the original implantation had occurred over a range of 6-15 years prior to the IOL exchange. Light transmission was decreased in all affected lenses compared to a similar control IOL. CONCLUSIONS: Although only a few reports of cases in which glistening and SSNG have progressed to the level of decreased visual function have been published, the likelihood is that this phenomena will increase as the severity and incidence of these inclusions have been shown to increase with time. Appropriate evaluations of visual function in such patients are needed and consideration should be given to IOL exchange in symptomatic patients.

Glistening in glaucomatous eyes: visual performances and risk factors.

PURPOSE: To analyse risk factors and visual performances of glaucomatous eyes with glistening in the intra-ocular lens (IOL). METHODS: Prospective study performed between November 2010 and April 2011 and involving 67 consecutive glaucomatous eyes (47 patients), who previously had a phacoemulsification with a hydrophobic acrylic IOL implanted in the capsular bag. Glistening was classified in three groups of severity grade: G0 (<50 microvacuoles per mm(2) ), G1 (50-150 microvacuoles per mm(2) ), and G2 (>150 microvacuoles per mm(2) ). All eyes underwent a best-corrected visual acuity evaluation (BCVA, LogMAR scale), a complete clinical examination, a visual field test, a contrast sensitivity evaluation and a wavefront analysis of high-order aberrations (HOAs) using a Shack-Hartmann aberrometer. Eyes with a posterior capsular opacification and a BCVA>0.30 LogMAR were excluded. RESULTS: Twenty six eyes (38.8%) had a grade 0, 12 eyes (17.9%) a grade 1 and 29 eyes (43.3%) a grade 2 of glistening severity grade. The mean follow-up after cataract surgery was 35.2 ± 24.2 months and was significantly higher for G1 and G2 groups (p < 0.001). A higher number of topical glaucoma medication were associated with a higher glistening severity grade (p < 0.05). G1 and G2 groups had significantly lower mean contrast sensitivity values at high spatial frequencies and significantly higher loss variance (LV) values of the visual field test (p < 0.05). There was no significant difference in mean BCVA between groups (p = 0.455). CONCLUSIONS: In glaucomatous eyes, glistening increased with time was associated with the number of topical glaucoma medications daily instilled and altered visual performances. It should be a consideration for glaucoma patients who are more likely to develop glistening within the IOL optic.

Effect of Glistening-Free Intraocular Lens on Intraocular Straylight

PURPOSE: To compare intraocular straylight between glistening-free and conventional intraocular lenses in pseudophakic eyes. METHODS: Straylight values were measured prospectively in 21 eyes with glistening-free pseudophakic lenses (group A, model enVista(TM), Bausch & Lomb, Inc., USA) and 79 eyes with conventional hydrophilic pseudophakic lenses (group B, model Akreos MI-60, Bausch & Lomb, Inc., USA). Best corrected visual acuity (BCVA) and straylight were measured preoperatively and 1 month and 2 months postoperatively using C-quant straylight meter (Oculus GmbH, Wetzlar, Germany). RESULTS: There were no statistically significant differences of BCVA preoperatively or 2 months postoperatively between the 2 groups (p > 0.05). BCVA and straylight significantly improved after the operation (p 0.05). CONCLUSIONS: In terms of straylight, glistening-free intraocular lenses were not beneficial. Although straylight was not statistically significant, other correlations between glistening and visual function should be investigated.