Hydrophobic Acrylic Intraocular Lens Research Articles

Comparison of the functional visual outcomes in pseudophakic patients implanted with different intraocular lenses

A good functional visual outcome after meticulous cataract surgery and intraocular lens implantation is the ultimate aim of every eye care practitioner. Combining the measurement of functional acuity contrast sensitivity testing along with visual acuity testing adds to our knowledge of visual performance. This study aims at assessing the functional visual outcome before and after cataract surgery with different IOL materials. Aims: To evaluate ,compare and analyse the visual outcome and contrast sensitivity functions in pseudophakic patients with hydrophobic acrylic, hydrophilic acrylic, spherical silicone and aspheric silicone intraocular lenses using the high contrast sensitivity Snellen's chart as well as low contrast sensitivity Sloan letter chart before and after cataract surgery Material and Methods: Retrospective, Randomised study, conducted over a period of 2 years from January 2004 to December 2005 at a tertiary eye care institute in Chennai. Results: The aspheric silicone IOL may provide an improvement in the quality of vision as measured by our clinical results of contrast sensitivity testing followed by the hydrophobic acrylic IOL and the hydrophilic Acrylic and the spherical silicone IOL. Keywords: Contrast Sensitivity, Functional Visual Acuity, Aspheric IOL, Pseudophakia

Technique for Sutured Scleral Fixation of One-Piece Hydrophobic Acrylic Intraocular Lenses Dislocated Into the Vitreous.

To present a suturing technique for safe refixation of posteriorly dislocated one-piece hydrophobic acrylic intraocular lenses (IOLs). Retrospective data analysis of a series of 12 cases operated with vitrectomy, followed by IOL relocation to the retropupillary area, after which polypropylene sutures are passed through the optic-haptic junctions of the dislocated IOL and subsequently secured to the sclera. In all cases, the IOL remained centered throughout the follow-up period (mean 10.5 months, range 3 weeks-36 months). One case was complicated by vitreous hemorrhage the first postoperative day and later cystoid macular edema. Visual acuity was not compromised at the end of follow-up. The presented technique is safe and provides long-term stable refixation in cases of late posterior dislocation of a one-piece hydrophobic acrylic IOL. The risk that sutures looped around haptics will slip off the haptic is thereby avoided.

Microscopic Characteristics of Late Intraocular Lens Opacifications

The increases in overall life expectancy and in lens surgeries performed on younger patients have resulted in a significant increase in the anticipated duration of artificial intraocular lenses (IOLs) in the eye. Thus, the physicochemical properties of the IOL become a critical issue, and several types of postoperative IOL opacifications have been reported. To describe the microscopic characteristics of opacified IOLs. Glistenings and subsurface nanoglistenings are fluid-related phenomena developing mainly in hydrophobic acrylic IOLs and are associated with aqueous influx into the IOL matrix. Calcification presents in hydrophilic acrylic or silicone IOLs as deposits of hydroxyapatite or other phases of calcium. Snowflake degeneration is less common, and it manifests in older polymethyl methacrylate IOLs. PubMed and ScienceDirect databases were searched for the following keywords: intraocular lens, IOL, cataract surgery, phacoemulsification, opacification, glistening, subsurface nanoglistenings, calcification, snowflake degeneration. English-language articles published up to October 15, 2019 were included in the study. The manuscript contains mainly a literature review; however, it was supplemented with original investigations from the David J. Apple International Laboratory for Ocular Pathology. Glistenings and subsurface nanoglistenings should be evaluated in a hydrated state and at room temperature; they manifest as microvacuoles sized from 1.0 to greater than 25.0 μm and less than 200 nm, respectively. Calcification deposits are situated on or underneath the surface of the IOL and can be stained with a 1% alizarin red solution or with the von Kossa method. Snowflake degeneration manifests as "particles" or "crystals," causing whitish IOL discoloration. Scanning electron microscopy or energy dispersive X-ray spectroscopy may improve the diagnostic accuracy.

The assessment of the impact of glistening on visual performance in relation to tear film quality.

The aim of our case control study was to evaluate the impact of glistening and tear film quality on visual performance after implantation of two different hydrophobic acrylic intraocular lenses (IOLs). In our retrospective study we included cataract patients operated between January 1, 2011 and December 31, 2012, with follow-up controls between January 2016 and December 2019. Z-Flex 860FAB (Medicontur) and AcrySof IQ SN60WF (Alcon) monofocal IOLs were implanted during standard phacoemulsification. Best corrected distance visual acuity (BCDVA) and contrast sensitivity were monitored over the post-operative period of up to 6 years. Glistening was evaluated semi-quantitatively with slit-lamp biomicroscopy and quantitatively using Pentacam HR (Oculus). Using HD Analyzer OQAS (Visiometrics), total intraocular light diffusion was interpreted with the objective scatter index (OSI) and tear film quality was evaluated with the tear film related objective scatter index (TF-OSI). 26 eyes implanted with the Z-Flex and 25 eyes with the AcrySof IQ IOLs were included in the analysis. The slit-lamp evaluation of patients with the Z-Flex IOL (0.57 ± 0.60) revealed significantly less glistening (p<0.0001), compared to the AcrySof IQ group (1.82 ± 0.90), and these observations were confirmed by the Pentacam HR analyses, as well (Z-Flex group: 35.1 ± 1.63, Acrysof IQ: 39.6 ± 3.69, p<0.0001). TF-OSI differed between the two sets of patients remarkably (1.53 ± 1.03 vs. 2.51 ± 1.76 for AcrySof IQ and Z-Flex groups, respectively, p = 0.043). Both groups of patients provided similar results of BCDVA and contrast sensitivity. Glistening and tear film quality both contribute to visual performance outcomes after cataract surgery. In our study the advantage of less glistening in the Z-Flex IOL might have been masked by the adverse effects of the more pronounced tear film insufficiency of these patients, compared to the AcrySof IQ group. Among other factors, tear film quality should also be taken into consideration when comparing the impact of glistening on visual quality of patients implanted with different IOLs.

Proliferative Anterior Optic Membranes in Hydrophobic Acrylic Intraocular Lenses.

PurposeTo describe the observed stages of development and management of proliferative anterior optic membranes (AOM) seen on a popularly implanted single-piece hydrophobic intraocular lens (IOL).MethodsThis is an observational series of patients with AOMs managed by three surgeons in different geographical areas in the USA.ResultsAOMs may clinically present in one of the four distinct stages. Most patients were visually asymptomatic, but those with decreased visual acuity (Stage 4) required Nd:YAG laser treatment to remove the AOM. These patients had improved visual acuity without recurrence of the AOM during the one-year follow-up period.ConclusionAOMs can present and progress in four distinct stages with variable visual significance. AOMs may be safely and effectively treated with Nd:Yag laser. Occurrence of the membrane may be related to many factors, including high fibronectin content of this IOL. Additional studies are needed to identify incidence, etiology, and best management strategies.

Changes in Opacification of Hydrophobic Acrylic Intraocular Lenses According to Temperature and Hydration.

PurposeTo investigate optic opacification of hydrophobic acrylic intraocular lens (IOL) depending on hydration and temperature conditions.MethodsIOL (Acrysof® MA60BM Alcon, Fort Worth, Texas, USA) extracted from a 55-year-old male who underwent binocular cataract 11 years ago were used for the analysis. On slit lamp examination, the binocular IOL optics showed homogenous opacification. After extraction of the IOLs, the IOL opacification disappeared during dry storage at 4°C. To investigate the changes in IOL opacification according to temperature and hydration, an extracted IOL was stored in either dry conditions or normal saline at 4°C, room temperature, or 37°C for 24 hours, and then the degree of haziness was examined. To investigate the impact of an opaque optic on visual function, light transmission was performed using an ultraviolet-visible spectrophotometer (U-3000, Hitachi High-Technologies Corp., Tokyo, Japan).ResultsThe extracted IOL optics at 4°C, room temperature, and 37°C were transparent at dry conditions. When the dried IOL was immersed in normal saline at room temperature and 37°C, opacification appeared. However, when the dried IOL was immersed in normal saline at 4°C, opacification of the IOL did not appear. When compared with the control, light transmission of the extracted IOLs from the right and left eyes stored in 37°C normal saline decreased by 4.7% at 453 nm and by 5.1% at 482 nm, respectively.ConclusionIn acrylic hydrophobic IOLs, optic opacification can occur depending on temperature and hydration conditions.

Capsular bag performance of a novel hydrophobic acrylic single-piece intraocular lens: Two-year results of a randomised controlled trial.

To determine the visual outcome, intraocular lens (IOL) stability and posterior capsule opacification (PCO) rate of a hydrophobic acrylic intraocular lens. Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria. This double-masked randomised study included patients who underwent standard cataract surgery. Patients received either the hydrophobic acrylic IOL (iPure, PhysIOL) or the hydrophobic acrylic control IOL (Tecnis ZCB00, Johnson&Johnson). Subjective refraction, uncorrected and corrected distance visual acuity (UDVA, CDVA), IOL tilt and decentration (Purkinje meter) and PCO intensity using retroillumination images with automated image analysis (automated quantification of after-cataract, AQUA), were evaluated for both groups 2 years after surgery. A total number of 31 patients completed the 2-year follow-up, 16 in the study group and 15 in the control group. The CDVA was 0.0 logMAR (standard deviation - SD: 0.1) for the study IOL and 0.1 logMAR (SD: 0.2) for the control IOL, p = 0.001. The AQUA PCO score for the study group was 2.1 and 1.4 for the control group, p = 0.44. Mean IOL tilt was 2.9° (SD: 1.8) in the study group and 5.0° (SD: 4.5) in the control group, whilst the mean decentration was 0.37 mm (SD: 0.18) and 0.45 mm (SD: 0.3), p = 0.610. The studied parameters revealed a good performance for both IOLs. Both IOLs had good CDVA, a small amount of tilt and decentration and none of the patients required laser capsulotomies during the follow-up time of 2 years after surgery.Presented at the 37th ESCRS Congress Paris, France, September 2019.

Comparison of polymethylmethacrylate versus hydrophobic acrylic lenses for primary intraocular lens implantation in pediatric cataract surgery

AIM: To compare the visual results and postoperative complications of polymethylmethacrylate (PMMA) and hydrophobic acrylic intraocular lenses (IOLs) in children who underwent cataract extraction with primary IOL implantation. METHODS: This retrospective study included 117 eyes of 63 children with bilateral pediatric cataract undergoing cataract surgery and primary IOL implantation. The patients were divided into two groups, Group I included 58 eyes of 30 patients with PMMA IOLs; Group II included 59 eyes of 33 patients with hydrophobic acrylic IOLs. The clinical features, refraction errors, best corrected visual acuity (BCVA) and surgical complications were compared between two groups. RESULTS: The mean age at the time of surgery was 5.8 (2-12)y and mean follow up period was 40.5 (6-196)mo. Postoperatively, BCVA was ≥0.5 in 80 eyes (68.4%) and this was comparable in two groups. Visual axis opacification was seen in 28 eyes (48.3%) in Group I and 16 eyes (27.1%) in Group II and this difference was statistically significant (P=0.018). Postoperative IOL dislocation and posterior synechia formation were also noted. When all postoperative complications were considered, there were significantly less complications in the acrylic IOL group than PMMA IOL group (P=0.020). CONCLUSION: Pediatric cataract surgery with primary IOL implantation is a safe procedure. Hydrophobic acrylic IOLs may lead to less postoperative complications compared to PMMA IOLs.

Intraocular Lens Power, Myopia, and the Risk of Nd:YAG Capsulotomy after 15,375 Cataract Surgeries.

The present study estimated the 5-year cumulative probability of Nd:YAG laser posterior capsulotomy according to the diopter power of implanted hydrophobic acrylic intraocular lenses (IOLs). Data were retrospectively collected of 15,375 eyes having cataract surgery and in-the-bag implantation of hydrophobic acrylic monofocal IOLs at the Ophthalmology Unit of Kymenlaakso Central Hospital, Kotka, Finland between the years 2007 and 2016. The cumulative probability of Nd:YAG capsulotomy was calculated by Kaplan–Meier estimates, and potential risk factors were analyzed using the Cox proportional hazards model. The 5-year cumulative probability of Nd:YAG capsulotomy after cataract surgery was 27.4% (95% confidence interval (CI) 22.9–32.6%) for low-diopter (5–16.5 D) IOLs, 14.6% (13.8–15.5%) for mid-diopter (17–24.5 D) IOLs, and 13.6% (11.7–15.6%) for high-diopter (25–30 D) IOLs. A multivariate Cox regression analysis showed that low-diopter IOLs (HR 1.76; 95% CI 1.38–2.25; p < 0.001) were associated with an increased risk of Nd:YAG capsulotomy compared to mid-diopter IOLs over the follow-up period after accounting for other predictors. Real-world evidence shows that low-diopter IOLs are associated with significantly higher risk of Nd:YAG capsulotomy within five years following implantation. Estimation should help in evaluating the risks of cataract surgery in myopic eyes.

Comparison of surgical repositioning rates and outcomes for hydrophilic vs hydrophobic single-piece acrylic toric IOLs.

To evaluate the comparative rotational stability and the repositioning rates and outcomes of a hydrophilic and hydrophobic acrylic monofocal toric intraocular lens (IOLs). Single center, Aravind Eye Hospital in Madurai, India. Retrospective cohort study. All patients had either an Auroflex hydrophilic acrylic toric IOL (n = 4603) or AcrySof hydrophobic acrylic toric IOL (n = 926) implanted between January 2015 and April 2019. Surgical repositioning was offered if the toric IOL was 15 degrees or greater misaligned or there was a 2-line or greater improvement in uncorrected distance visual acuity (UDVA) predicted with repositioning. A total of 5529 single-piece toric IOLs were implanted during the study period. There was no statistically significant difference between the hydrophilic and hydrophobic acrylic toric IOL groups in need for surgical repositioning (2.5% vs 1.9%; P = .34) or actual surgical repositioning rate (1.8% vs 1.5%; P = .59). A higher rate of surgical toric IOL repositioning was associated with younger age (62.7 vs 67.2 years; P < .0001), higher presurgical astigmatism (2.32 vs 1.99 diopters [D]; P < .0001), and with-the-rule astigmatism (4.7% vs 2.1% against-the-rule astigmatism; P = .002). In 95 eyes that underwent toric IOL repositioning, there was significant preoperative to postoperative improvement in UDVA (0.48 vs 0.12 logarithm of the minimum angle of resolution; P < .001), mean residual cylinder (1.79 vs 0.7 D; P < .001), and mean toric IOL misalignment (49.7 vs 5.4 degrees; P < .001). The repositioning outcomes were statistically similar with both toric IOL models. There were no major complications or recurrent toric IOL rotation after surgical repositioning. The hydrophilic acrylic toric IOL had comparable rates of postoperative misalignment and surgical repositioning with the hydrophobic acrylic toric IOL. Early postoperative surgical repositioning was both safe and effective with both toric IOLs.

Refractive stability of a new single-piece hydrophobic acrylic intraocular lens and corneal wound repair after implantation using a new automated intraocular lens delivery system

PurposeTo investigate refractive stability and characterize corneal incision repair up to 3 months after implantation of a new hydrophobic acrylic intraocular lens (IOL) with hydroxyethylmethacrylate using a new automated IOL delivery system.MethodsThis prospective case series included 50 eyes of 50 patients undergoing phacoemulsification and implantation of the Clareon® CNA0T0 IOL using the AutonoMe® automated delivery system in the Department of Ophthalmology, Keio University School of Medicine. The clinical data were collected from 46 eyes of 46 patients preoperatively and 1 day, 1 week, and 1 and 3 months postoperatively. Endothelial-side incision gaping, posterior incision retraction, and Descemet’s membrane detachment were recorded as present or absent using anterior-segment optical coherence tomography postoperatively.ResultsThe uncorrected distance and corrected distance visual acuities improved and stabilized 1 week postoperatively. The anterior chamber depth was stable from 1 week postoperatively. The subjective refraction was stable from 1 day postoperatively. Descemet’s membrane detachments and endothelial-side wound gaping were seen in 19 (41.3%) eyes and 34 (73.9%) eyes 1 day postoperatively and decreased gradually. Posterior incision retraction was seen in eight eyes (17.4%) on day 1 and increased to 19 eyes (41.3%) 3 months postoperatively.ConclusionsThe Clareon IOL had excellent refractive stability from day 1 postoperatively. The AutonoMe automated delivery system enables safe IOL implantation through a 2.4-mm corneal incision, although the wound required longer than 1 month to heal postoperatively.

Long-term uveal and capsular biocompatibility of a new fluid-filled, modular accommodating intraocular lens.

To evaluate long-term uveal and capsular biocompatibility of a new fluid-filled modular accommodating intraocular lens (IOL) consisting of base and fluid lenses. John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA. Experimental study. Bilateral phacoemulsification was performed on 8 rabbits; 1 eye received the test IOL (Juvene) and the other a hydrophobic acrylic control IOL (SA60AT). Slitlamp examinations were performed at postoperative weeks 1 and 4, and at months 2, 3, and 6. The rabbits were killed humanely at 6 months. After gross examination from the Miyake-Apple view, IOLs were removed for implant cytology. All globes were then processed for histopathologic examination. Uveal biocompatibility was similar between test and control IOLs up to 6 months postoperatively. Anterior capsule opacification appeared absent in the test group, and posterior capsule opacification (PCO) was significantly less in comparison with the control group throughout the study. At 6 months, central PCO was scored as 0.12 ± 0.23 with test IOLs and as 4.0 ± 0 with control IOLs (P < .0001, 2-tailed t test: paired 2-sample for means). Histopathologic examination confirmed the relative lack of capsular opacification in test eyes in comparison to controls and the absence of toxicity in any eye. Six weeks in the rabbit model corresponds to approximately 2 years in the human eye for PCO. In this model, the Juvene IOL maintained an open and expanded capsular bag, preventing overall capsular bag opacification while retaining excellent uveal and capsular biocompatibility.

Serial opacification of a hydrophilic-hydrophobic acrylic intraocular lens: analysis of potential risk factors.

To identify potential risk factors related to the opacification of a hydrophilic-hydrophobic acrylic intraocular lens (IOL) model. University Hospital Regensburg, Department of Ophthalmology, Regensburg, Germany. Cross-sectional study. All patients with a Lentis LS-502-1 IOL implanted at the Department of Ophthalmology were identified. Existing medical records and information from the treating ophthalmologists were reviewed to determine the IOL status (clear or opacified). Potential risk factors were analyzed using binary logistic regression models. A total of 223 IOLs of 199 patients were included. Sixty-seven (30.0%) opacified (calcified) IOLs were identified and compared with a control group of 156 IOLs. Statistical analyses revealed age at IOL implantation (odds ratio [OR] = 1.05, P = .012) to be associated with an increased risk of calcification. Posterior capsulotomy (OR = 0.45, P = .011) was found to have a protective influence. No other ophthalmic or systemic condition showed a significant association. Mean corrected distance visual acuity diminished significantly under opacification from 0.21 ± 0.25 logarithm of the correct minimum angle of resolution (logMAR) to 0.42 ± 0.32 logMAR (P < .001). IOL exchange in 55 of 67 cases at 45.8 ± 20.5 months after initial implantation yielded significant visual recovery (P = .001). Age at implantation might be a risk factor of IOL calcification, whereas posterior capsulotomy might be a protective factor. Calcification of the LS-502-1 IOL might be caused by the interaction of 3 main factors: IOL material traits, manufacturing-associated contamination, and patients' individual factors altering intraocular ion concentrations.

Comparison of Long-Term Rotational Stability of Three Commonly Implanted Intraocular Lenses

To compare rotational stability and its influencing factors in 3 different widely used hydrophobic acrylic intraocular lenses (IOLs) from the end of surgery (EoS) to 4-7months (6months) in over 380 eyes. Prospective interventional comparative clinical study. Setting: Department of Ophthalmology, Medical University of Vienna. A total of 381 eyes of 199 patients with age-related cataract received an IOL Acrysof SN60WF, Tecnis ZCB00, or Envista MX60 in a consecutive order. Implantation of an Acrysof, Tecnis, or Envista IOL randomized to the 0 ± 10, 45 ± 10, 90 ± 10, or 135 ± 10° axis in 1 or both eyes. Baseline measurement was performed with patients supine still on the operating table. Postoperative follow-ups were conducted after 1 hour, 1week, 1month, and 6months. Difference of absolute rotation from the EoS to 6months. Absolute rotations from the EoS to 6months were 1.65 ± 2.1, 2.65 ± 4.1, and 3.18 ± 5.8° for the Acrysof, Tecnis, and Envista group, respectively. Rotational stability was statistically significantly superior in the Acrysof compared with the Envista group (P= .014), but not compared with the Tecnis group (P= .10). No significant difference was found between the Tecnis and Envista groups (P= .761). Maximum values of 15.8, 38.6, and 44.9° were observed for the Acrysof, Tecnis, and Envista group, respectively. The Acrysof IOL showed the least amount of absolute rotation compared with the Tecnis and Envista IOLs. Outliers possibly requiring secondary intervention were observed in all groups. The amount of rotation was greatest during the first postoperative hour.

In vitro glistening formation in IOLs: automated method for assessing the volumetric density and depth distribution of microvacuoles.

To develop a method to measure the depth profile of microvacuoles (MVs) in intraocular lenses (IOLs) and to characterize, after accelerated aging, the glistening of an acrylic hydrophobic IOL. University of Milano-Bicocca, Milan, Italy. In vitro study. A heat treatment was applied in vitro to Basis V IOLs exposed to deionized water (24 hours at 45 ± 1°C, rapid cooling, and 24 hours at 24 ± 1°C). Thirty images (area 1.2 mm) of each IOL were acquired by a microscope, focusing on sequential planes every 23 ± 2 μm. By tracking the traces of each MV in consecutive images, the coordinates of the MV centroids along the IOL thickness were construed by an automated procedure, and in the generated single-focus stacked image, MVs were counted by an automated method. MV density was found normally distributed along the IOL depth profile (Jarque-Bera test). In focus-stacked images, the MV automated counting was found accurate within 5% vs manual counting, and MV volume density of the order of 10 mm was estimated. It was observed that stacks of 15 images provided a 4% lower MV volume density compared with the stacking of 30 images. The assessment of the number of MVs by the acquisition of a single image of an IOL was influenced by the distance of the selected plane from the IOL surface. The decrease in MV density approaching the IOL edges can be explained as a consequence of the diffusion of water toward the external environment after accelerated aging.

Glistening formation in a new hydrophobic acrylic intraocular lens

BackgroundThe formation of fluid-filled microvacuoles, termed glistenings, is a common complication of intraocular lenses (IOLs) made from hydrophobic acrylate. Using our well-established in-vitro laboratory method, we evaluated a new IOL material’s resistance to glistening formation.MethodsAn in-vitro stress test for glistening induction was performed on 20 samples of hydrophobic acrylic IOLs: ten of the new Eyecryl ASHFY600 (Biotech Vision Care, Ahmedabad, India) compared with ten samples of AcrySof IQ SN60WF (Alcon, Fort Worth, USA). The number of microvacuoles per square millimetre (MV/mm2) was evaluated in five sections of each IOL. The results for each model were compared and rated on a modified Miyata Scale for grading glistening severity.ResultsIn all cases, glistening number was higher in the central section of the IOL optic than in the periphery. Mean number of MV/mm2 was highest in the central part of the AcrySof IQ SN60WF, with 41.84 (±27.67) MVs/mm2. The lowest number of glistenings was found in the five sections of the Eyecryl ASHFY600 with 0.52 (±0.24) MVs/mm2. Mean value of the Eyecryl ASHFY600 IOL, using the Miyata Scale, was Zero.ConclusionIn this in-vitro laboratory study, the new hydrophobic acrylic IOL showed a high resistance to microvacuole formation. Results from this in-vitro study suggest that glistening numbers will be low in clinical use in the Eyecryl ASHFY600.

Posterior Capsule Opacification With Two Hydrophobic Acrylic Intraocular Lenses: 3-Year Results of a Randomized Trial

To compare the incidence and intensity of posterior capsule opacification (PCO) and neodymium-yttrium-aluminum-garnet (Nd:YAG) capsulotomy rates between 2 similar open-loop single-piece hydrophobic acrylic intraocular lenses (IOLs) that differ in the proprietary material characteristics and design features, over a period of 3 years. Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison. Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. Eighty patients (160 eyes) had bilateral cataract surgery and received a Vivinex XY1 IOL in 1 eye and an AcrySof SN60WF IOL in the other eye. Follow-up examinations were performed 3 years after surgery. Digital retroillumination images were taken of each eye. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (AQUA). PCO score (scale, 0-10). The mean objective PCO score of the Vivinex XY1 IOLs was 0.9 ± 0.8 compared to the PCO score of 1.4 ± 1.1 for the AcrySof SN60WF IOLs (P < .001). Three years postoperatively, 11.4% of patients had an Nd:YAG capsulotomy in the Vivinex XY1 eye and 18.6% had a capsulotomy in the AcrySof SN60WF eye (P= .23). The new hydrophobic acrylic Vivinex XY1 IOL showed significantly lower PCO rates and lower YAG rates compared to the AcrySof SN60WF IOL. The interaction of various factors such as hydrophobic material, smooth optic surface, and sharp posterior optic edge plays a key role in PCO development.

Explantation of a glistening-free, hydrophobic acrylic intraocular lens with cosmetic imperfections on the lens surface

The enVista intraocular lens (IOL), model MX60E is a single-piece hydrophobic acrylic lens that became available in early 2018. Several months later, certain lot numbers were recalled by the manufacturer due to reports of cosmetic imperfections on the IOL surface. We describe a case of an enVista IOL, model MX60E, exhibiting such cosmetic imperfections, which was explanted due to unwanted optical symptoms, from a patient with a medical history of sarcoidosis. Laboratory evaluation of the explanted lens revealed the presence of multiple concentric rings throughout the surface of the optic component, which appeared to correspond to manufacturing marks. The patient's undesired visual symptoms resolved after IOL exchange.

Supercritical loading of gatifloxacin into hydrophobic foldable intraocular lenses - Process control and optimization by following in situ CO2 sorption and polymer swelling.

The supercritical impregnation process was used as a green technology for the elaboration of drug delivery intraocular lenses to mitigate the risk of post-operatory endophthalmitis after cataract surgery. Commercially available hydrophobic acrylic (copolymer of benzyl methacrylate and methyl methacrylate) intraocular lenses (IOLs) were impregnated with gatifloxacin, a fourth generation fluoroquinolone drug, using pure supercritical CO2 (scCO2) to obtain solvent-free loaded implants. The interaction phenomena involved in the supercritical impregnation were studied by following in situ scCO2 sorption within the polymer support and the subsequent IOL swelling, and by taking into account drug solubility in the supercritical fluid phase. The drug impregnation yields determined though in-vitro release studies varied between 0.33 and 1.07±0.07μg·mg-1IOL in the studied experimental conditions (8 to 25MPa, 308 to 328K and 30 to 240min impregnation duration). An impregnation duration longer or equal to the time required for a complete CO2 uptake by the polymer as well as a higher pressure or a higher temperature over the crossover pressure delimiting the upper limit of the retrograde solubility zone, led to higher drug impregnation yields.

Uveal and capsular biocompatibility of a new hydrophobic acrylic microincision intraocular lens

To evaluate uveal biocompatibility and capsular bag opacification of a new hydrophobic acrylic microincision intraocular lens (IOL) in comparison with a commercially available 1-piece hydrophobic acrylic IOL. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Eight New Zealand rabbits underwent bilateral phacoemulsification and implantation of the preloaded Nanex multiSert IOL in one eye and a commercially available preloaded lens (AcrySof IQ in UltraSert, model AU00T0) in the contralateral eye. A slitlamp examination was performed weekly for 4 weeks. The rabbits were then killed humanely and their globes enucleated. Capsular bag opacification was assessed from the Miyake-Apple view, and the eyes were subjected to histopathologic evaluation. Postoperative inflammatory reactions were similar between the test and control eyes in the 8 New Zealand rabbits. The mean postmortem central posterior capsule opacification (PCO) was 0.93 ± 0.73 in the test group and 1.19 ± 0.53 in the control group. The mean postmortem peripheral PCO was 1.75 ± 0.92 in the test group and 2.06 ± 0.77 in the control group. Central and peripheral PCO scores were not statistically different between the test and control groups (P = .41 and P = .35, respectively, 2-tailed t test: paired 2-sample for means). A new 1-piece hydrophobic acrylic microincision IOL incorporating an ultraviolet-ozone treatment on the posterior surface performed similarly to a commercially available 1-piece hydrophobic acrylic IOL in terms of uveal and capsular biocompatibility in the rabbit model. To our knowledge, this is the first hydrophobic acrylic microincision IOL to demonstrate similar PCO performance when compared with a conventional, commercially available IOL.