Uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses

Zwitterionic modified and freeze-thaw reinforced foldable hydrogel as intraocular lens for posterior capsule opacification prevention

Posterior capsule opacification (PCO) is a predominant postoperative complication, often leading to visual impairment due to the aberrant proliferation and adhesion of lens epithelial cells (LECs) and protein precipitates subsequent to intraocular lens (IOL) implantation. To address this clinical issue, a foldable and antifouling sharp-edged IOL implant based on naturally-derived cellulose hydrogel is synthesized. The mechanical strength and transparency of the hydrogel is enhanced via repeated freeze-thaw (FT) cycles. The incorporated zwitterionic modifications can remarkably prevent the incidence of PCO by exhibiting proteins repulsion and cell anti-adhesion properties. The graft of dopamine onto both the haptic and the periphery of the posterior surface ensures the adhesion of the hydrogel to the posterior capsule and impedes the migration of LECs without compromising transparency. In in vivo study, the zwitterionic modified foldable hydrogel exhibits uveal and capsular biocompatibility synchronously with no signs of inflammatory response and prevent PCO formation, better than that of commercialized and PEG-modified IOL. With foldability, endurability, antifouling effect, and adhesive to posterior capsule, the reported hydrogel featuring heterogeneous surface design displays great potential to eradicate PCO and attain post-operative efficacy after cataract surgery.

Reversible Multifocality Achieved Through Polypseudophakia

Simultaneous implantation of a monofocal or monofocal toric intraocular lens (IOL) into the capsular bag and a multifocal IOL into the ciliary sulcus, referred to as duet procedure, allows us to create multifocality that is more easily reversible than the implantation of a capsular bag-fixated multifocal IOL. The optical quality and results after the duet procedure are equivalent to those of a capsular bag-fixated multifocal IOL. Patients who cannot tolerate the side effects of multifocal optics or who develop an ocular condition leading to loss of function such as age-related macular degeneration (AMD) or glaucoma in the course of their lives may benefit from the reversibility of the procedure.

Preclinical biocompatibility and biosafety evaluation of a new foldable brown diaphragm intraocular lens: An in vitro and in vivo study

BACKGROUND

A new foldable brown diaphragm intraocular lens (IOL) was preclinically evaluated in vitro and in vivo by comparing its biocompatibility and biosafety with those of a commercially available IOL.

METHODS

The new foldable iris-diaphragm IOL is composed of hydrophobic acrylic material, with a transparent optical zone and surrounding brown diaphragm. Cellular experiments evaluating lens epithelial cell morphology, adhesion, and migration were conducted to exclude cytotoxic effects. Twelve New Zealand rabbits underwent implantation of a brown diaphragm IOL in one eye, whilst an additional 12 had a commercially available foldable IOL implanted, followed by slit-lamp evaluations of inflammatory reactions and capsular opacification. Corneal endothelial cells density was measured before and after implantation. Aqueous humour samples were obtained weekly for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis to investigate dye leakage from the brown-diaphragm IOL. Following 12 weeks of observation, haematoxylin and eosin staining of ocular tissue and scanning electron microscopy (SEM) of the IOL surface were performed.

RESULTS

Results from in vivo experiments found no statistically significant differences between the two groups in terms of postoperative inflammation and capsular biocompatibility. No significant changes in corneal endothelial cell density were observed in either group before and after surgery. LC-MS/MS analysis showed that the target dye was not detected in aqueous humour samples. Histopathology of ocular sections and SEM imaging of IOL surfaces showed similar changes in both groups.

CONCLUSIONS

The newly invented IOL showed good biocompatibility and biosafety. Combined with its foldability and peripheral shading, it could be a new choice for patients with iris defects.

Biomedical Silicones: Leveraging Additive Strategies to Propel Modern Utility

Silicones have a long history of use in biomedical devices, with unique properties stemming from the siloxane (Si-O-Si) backbone that feature a high degree of flexibility and chemical stability. However, surface, rheological, mechanical, and electrical properties of silicones can limit their utility. Successful modification of silicones to address these limitations could lead to superior and new biomedical devices. Toward improving such properties, recent additive strategies have been leveraged to modify biomedical silicones and are highlighted herein.

The outcomes of cataract surgery in eyes with Fuchs uveitis

BACKGROUND

To evaluate clinical results in eyes undergoing phacoemulsification intraocular lens (IOL) implantation due to Fuchs^, uveitis (FU) related complicated cataract.

METHODS

Post-surgical outcomes of 56 eyes of 55 FU patients were evaluated retrospectively. Three groups were formed according to the IOL model: hydrophilic SAF6125 (Optima fold) acrylic, hydrophobic SN60AT (Alcon), and hydrophobic AAB00 (Abbott). Postoperative posterior capsular opacification (PCO) development and PCO development time, neodymium number: YAG laser posterior capsulotomy rate, giant cell (GC) deposition on the IOL, and the development time of GC deposits were compared among the groups. All patients were followed postoperatively on the 1^st day, 1^st week, 2^nd and 6^th weeks, and then at 3-month intervals.

RESULTS

The hydrophilic SAF6125 IOL was implanted in 10 eyes, hydrophobic SN60AT in 24 eyes and AAB00 IOL in 22 eyes. The mean postoperative follow-up time was 34.1 ± 30.1 (6-144) months. PCO developed in 7 eyes (70%) in the hydrophilic SAF6125 group, 17 eyes (70.8%) in the hydrophobic SN60AT and 13 eyes (59.1%) in the AAB00 group. There was no statistically significant difference among the three IOL groups in the PCO development, the PCO development time and YAG laser capsulotomy rates (P = 0.674, P = 0.111, and P = 0.507, respectively). The PCO development time was significantly longer in the hydrophobic SN60AT than AAB00 group (P = 0.027). GC deposits were detected in 3 eyes (30%) in the hydrophilic SAF6125 group, 7 eyes (29.1%) in the hydrophobic SN60AT and 3 eyes (13.6%) in the AAB00 group. GC deposition and the development time of GC deposits were similar among the three IOL groups (P = 0.575, P = 0.804). At the final follow-up, BCVA was ≥ 20/40 in 41 eyes (73.2%).

CONCLUSION

The GC deposits and PCO development were the most important problems in these eyes with hydrophilic or hydrophobic IOLs despite good visual and postoperative results. New developments are needed in terms of IOL design or content in eyes with FU.

Factors influencing aqueous flare after cataract surgery and its evaluation with laser flare photometry

Despite the refinement of modern cataract surgery, postoperative inflammation still constitutes a substantial amount of visual morbidity worldwide. A surrogate for intraocular inflammation and blood-aqueous barrier breakdown can be objectively quantified by Laser flare photometry (LFP). This review outlines the utility of LFP in assessing the assessment of post-cataract surgery inflammation. It highlights the impact of preoperative pathological states such as uveitis and diabetes, intraoperative techniques, including efficient phacoemulsification and direct comparisons between postoperative anti-inflammatory regimes. There is a large interobserver variation in the subjective flare measurement after cataract surgery and the continued use of LFP amongst other objective, noninvasive measurements of intraocular inflammation, particularly in the further development of cataract surgery, is recommended.

Clinical outcomes with a low add multifocal and an extended depth of focus intraocular lenses both implanted with mini-monovision

OBJECTIVES

To compare the visual acuity, contrast sensitivity (CS), spectacle needs, photic phenomena, and quality of life parameters of patients bilaterally implanted with a low add multifocal (MIOL) or an extended depth of focus (EDOF) intraocular lens (IOL), both with intended mini-monovision.

METHODS

In this prospective, randomized, comparative study, patients were randomized to receive either Tecnis +2.75 D (ZKB00) (MIOL Group, n = 15) or Tecnis Symfony (ZXR00) (EDOF Group, n = 14) for bilateral implantation with mini-monovision (-0.50 D). Binocular logMAR uncorrected visual acuities (UVA), monocular defocus curves, CS with CSV 1000-E, and Pelli-Robson Test (PRT), spectacle needs and quality of life parameters with NEI RQL-42 questionnaire were evaluated at postoperative 1, 3, and 6 months.

RESULTS

Results of MIOL and EDOF Groups at postoperative month 6 are as follows: distance (6 m) UVA -0.03 ± 0.05 and -0.05 ± 0.06 (p = 0.938), intermediate (60 cm) UVA, 0.04 ± 0.08 and -0.03 ± 0.07 (p = 0.046); near (40 cm) UVA, 0.22 ± 0.08 and 0.15 ± 0.07 (p = 0.046); near spectacle needs, 26.7% and 14.3% (p > 0.05), respectively. Better visual acuity was achieved in the EDOF Group between the defocus range of -0.50 and -1.75 D (p < 0.05). No significant difference was found regarding photic phenomena and CS evaluated with CSV 1000-E between the two IOL groups at 6 months after surgery (otherwise there are differences at 1 and 3 months in favor of EDOF). However, EDOF Group performed better in mesopic CS evaluated with PRT (p < 0.05).

CONCLUSIONS

When implanted with mini-monovision better binocular uncorrected visual performance at intermediate and near distances achieved with EDOF than low add MIOL.

Clinical outcomes in patients after duet procedure for reversible trifocality using a supplementary trifocal IOL

PURPOSE

We report the clinical outcomes of patients who had primary lens implantation in the capsular bag and subsequently a supplementary trifocal lens implanted in the ciliary sulcus (duet procedure) to create reversible trifocality.

DESIGN

Retrospective interventional case series.

METHODS

Twenty-five patients were included in this single center clinical study, who had undergone either refractive lens exchange for presbyopia correction or cataract surgery. All had lens removal by phacoemulsification and duet procedure to achieve reversible trifocality. Preoperatively and three months postoperatively, uncorrected (UDVA) and corrected distance visual acuity (CDVA) were assessed, as well as uncorrected (UNVA), distance corrected (DCNVA) and corrected near visual acuity (CNVA). At the postoperative examination, uncorrected (UIVA), distance corrected (DCIVA) and corrected intermediate visual acuity (CIVA), defocus curve testing and dysphotopsia evaluation were also performed.

RESULTS

Monocular UDVA and CDVA improved from 0.71 ± 0.43 logMAR and 0.12 ± 0.16 logMAR preoperatively to 0.04 ± 0.10 logMAR and -0.01 ± 0.09 logMAR postoperatively. Monocular UNVA and DCNVA were both 0.06 ± 0.08 logMAR and UIVA and DCIVA 0.00 ± 0.10 logMAR and -0.02 ± 0.10 logMAR postoperatively. Monocular defocus curve testing revealed a visual acuity of 0.2 logMAR or better from +0.75 to -3.5 diopters.

CONCLUSIONS

Duet procedure using a trifocal supplementary IOL provided excellent results for far, near and intermediate distance, comparable to those reported for capsular bag fixated trifocal IOLs. The duet procedure offers the advantage of an exit-strategy in cases with a future loss of function or side effects associated with the optics.

Amphiphilic silicones to mitigate lens epithelial cell growth on intraocular lenses

Silicone intraocular lenses (IOLs) that resist lens epithelial cell (LEC) growth would greatly improve patient outcomes. Herein, amphiphilic surface modifying additives (SMAs) were incorporated into an IOL-type diphenyl silicone to reduce LEC growth without compromising opto-mechanical properties. The SMAs were poly(ethylene oxide)-silane amphiphiles (PEO-SAs) [H-Si-ODMS_m-block-PEO₈-OCH₃], comprised of a PEO segment and siloxane tether of varying lengths (m = 0, 13, and 30). These three SMAs were each blended into the addition cure diphenyl silicone at varying concentrations (5, 10, 15, 20, and 25 μmol g^-1) wherein the wt% of PEO was maintained for all SMAs at a given molar concentration. The chemical crosslinking and subsequent retention of SMAs in modified silicones was confirmed. Key material properties were assessed following equilibration in both air and aqueous environments. Silicones modified with SMAs having longer tethers (m = 13 and 30) underwent rapid and substantial water-driven restructuring of PEO to the surface to form highly hydrophilic surfaces, especially as SMA concentration increased. The % transmittance was also maintained for silicones modified with these particular SMAs. The moduli of the modified silicones were largely unchanged by the SMA and remained in the typical range for silicone IOLs. When the three SMAs were introduced at the highest concentration, modified silicones remained non-cytotoxic and LEC count and associated alpha-smooth muscle actin (α-SMA) expression decreased with increasing tether length. These results demonstrate the potential of silicones modified with PEO-SA SMAs to produce LEC-resistant IOLs.

Comparative analysis of postoperative results of cataract surgery using monofocal IOLs

 

One of the most common surgical interventions in ophthalmology today is lens replacement surgery. But there is still no consensus on whether the choice of a monofocal IOL affects the postoperative functional outcome.The aim: to conduct a comparative analysis of values of visual acuity without correction in the early postoperative period after cataract surgery using monofocal IOLs.Material and methods. The study included data of 2643 eyes operated for cataract, into which one of the monofocal IOLs, included in the top ten most frequently implanted IOLs in the Orenburg Branch of the S. Fyodorov Eye Microsurgery Federal State Institution, was implanted for the period 2019–2021. Statistical analysis was performed using the program Statistica 13.0.Results. The performed analysis of variance showed that the established differences between the compared groups are statistically signifi cant (p < 0.05). However, the subgroup analysis showed that there were statistically signifi cant differences between pairs such as Tecnis and Hydro-4; Tecnis and Rayner. In all other cases, statistically signifi cant uncorrected visual activity (UCVA) values after surgery were not established. It has also been reliably established that the presence of subluxation of the lens affects the value of UCVA after surgery.Conclusion. The results of the performed analysis in general indicate that the value of UCVA in patients in the early postoperative period after the performed surgical intervention does not depend on the manufacturer of the used IOL.

Intraoperative and Postoperative Intraocular Lens Opacifications: Analysis of 42545 Cases

Purpose

To assess the types and causes of intraocular lens (IOL) turbidity in a tertiary eye center. Setting. Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.

Design

Retrospective case series.

Methods

Patients who underwent uncomplicated phacoemulsification and IOL implantation for cataract between January 2015 and December 2019 were included. Medical records were reviewed of participants with intraoperative or postoperative IOL opacification for clinical data, artificial crystal materials, and causes of the opacification.

Results

A total of 42545 IOLs were implanted in the five years, comprising 25471 (66.0%) hydrophilic IOLs, 11881 (27.9%) hydrophobic IOLs, and 2601 (6.1%) hydrophilic-hydrophobic acrylic IOLs. Among the operated eyes, 14 eyes (13 patients) experienced IOL opacification, which was permanent for 10 IOLs, including 7 (0.6%) hydrophilic IOLs (860UV) and 3 (0.2%) hydrophilic-hydrophobic acrylic IOLs (L-312). The mean interval between surgery and diagnosis of permanent opacification was 34.4 ± 18.4 (SD) months (range, 12 to 59 months). Permanent IOL clouding led to a statistically significant reduction in best corrected visual acuity (mean, 0.64 ± 0.4 logMAR; P < 0.004). Acute IOL clouding occurred in four eyes during the implantation of a hydrophilic-hydrophobic acrylic IOL of L-312, 809M, or 839M and returned to transparency several hours later. All four procedures were performed in winter, with the mean outside temperature being −5.75°C.

Conclusions

The rate of IOL opacification was 0.03%. Both delayed postoperative and acute intraoperative opacifications occurred with various characteristics in IOLs made of different materials and designs. Clinicians should be aware of this risk for cataract surgery.

Clinical Features of Patients with Opacification of Hydrophilic Acrylic Intraocular Lens in Neovascular Glaucoma

Purpose: To report the clinical features of patients with opacification of hydrophilic acrylic intraocular lens (IOL) after cataract surgery in neovascular glaucoma.Methods: This retrospective case series included 11 eyes of 10 patients with IOL opacification and neovascular glaucoma (NVG) between January 2006 and December 2010. We included and analyzed cases with opacification of hydrophilic acrylic IOL. An IOL exchange was performed in three cases, and the explanted IOLs were examined grossly and evaluated by light microscopy. Sagittal sections of the optics of the IOLs were evaluated by Von Kossa staining, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX).Results: All 11 eyes of 10 patients were implanted with hydrophilic acrylic IOLs. In addition, there were no cases of hydrophobic acrylic IOL opacification. Nine patients of the 10 patients had diabetic retinopathy and one patient had central retinal artery occlusion. The mean period of IOL opacification after IOL implantation was 19.45 ± 8.52 months and the mean period of IOL opacification after the occurrence of NVG was 14.37 ± 8.51 months. The deposits of the explanted IOLs were shown to consist of calcium by von Kossa staining. The explanted IOLs showed fine whitish irregular granular deposits on the entire anterior surface of the optics by SEM and the presence of calcium deposition was confirmed by EDX analysis.Conclusions: Care is required when using hydrophilic acrylic IOLs in patients with risk of neovascular glaucoma, such as those with diabetic retinopathy or central retinal artery occlusion.

Study on buckling of intraocular lens haptic in 2 types of intraocular lens material and its effect on vision

Aim: To study the buckling of intraocular lens (IOL) haptics and its effect on vision in patients implanted with either hydrophilic or hydrophobic lens material. Study design: Prospective, observational and descriptive study. Setting: Tertiary eye care center in India. Material and methods: Patients operated for age-related cataract by phacoemulsification technique implanted with hydrophilic or hydrophobic IOL came either for follow-up surgery or complaints in an operated eye, being examined for visual acuity, refraction, anterior segment evaluation, and retinal examination. The position of IOL in terms of optic and haptics was noted and photographed. Results: 317 patients participated in the study. The mean age (SD) of the patients was 65 years (± 4.5). Of 317 patients, 127 (254 eyes) had bilateral, and 190 (190 eyes) had one eye IOL implantation. Out of 444 eyes, 254 (57.2 %) had hydrophilic and 190 eyes (42.8%) had hydrophobic IOL implantation. Buckling of IOL haptic was seen in 37 (8.3%) eyes of which 34 (13.9%) had hydrophilic, and 3 (1.6%) had hydrophobic IOL. Maximum eyes (n=20) with hydrophilic IOL presented during 1-3 years after IOL implantation. Major complaint for which patients came for follow up was blurring of vision (48.9%) and diminished vision (36.3%). Posterior capsular opacification (PCO) was observed in 2/ 190 (1.1%) eyes with hydrophobic and 28/ 254 (11%) eyes with hydrophilic IOL. Discussion: The present study dealt with the long-term performance of the haptics of the hydrophilic and hydrophobic IOLs in relation to its stability in the capsular bag. Conclusion: Buckling of haptic was seen more in the hydrophilic than in the hydrophobic IOLs. PCO was common in these eyes. Change in refraction occurred in eyes with hydrophilic IOL with buckling.

Analysis of YAG Laser-Induced Damage in Intraocular Lenses: Characterization of Optical and Surface Properties of YAG Shots

PURPOSE

To assess differences in neodymium:yttrium aluminum garnet (Nd:YAG)-induced defects in hydrophilic and hydrophobic intraocular lenses (IOLs) and describe optical and surface properties of YAG shots/pitting. Describing and measuring the iatrogenic produced defects should achieve higher awareness on this topic and change the mindset of such a trivial procedure to be proceeded with more caution and calmness in the future.

MATERIALS

Twelve IOLs from different manufacturers made of hydrophilic and hydrophobic materials were evaluated before and after treatment with the Nd:YAG laser. Microscopy and environmental scanning electron microscopic (ESEM) images were used to visually analyze the defects. Additionally, wavefront measurements were taken for power mapping and Raman spectroscopy was performed. Vertical and horizontal dimensions of the defects were analyzed and compared, and Raman line scans assessed the changes in the chemical structure in the defect area of the IOL.

RESULTS

Microscopically, pitting of the surface could be observed in both lens types. Defects in hydrophobic lenses appeared bigger and were visible with less magnification than in hydrophilic lenses. Similar results were obtained with ESEM images where the defects in hydrophobic IOLs seemed to be frayed while defects in hydrophilic IOLs were of circular shape. Raman spectroscopy revealed deeper defects in hydrophobic lenses. Vertical dimensions of the defects were statistically significant (p = 0.036) and greater in hydrophobic materials while horizontal dimensions did not reach significance (p = 0.056). The area of chemical changes was greater than the visible defect area and smaller in hydrophilic than that in hydrophobic materials.

CONCLUSION

Nd:YAG seems to have greater impact on hydrophobic IOL materials as that damage was greater and more frayed than that in hydrophilic materials. Moreover, there seems to be larger, distinctive damage area in IOLs (with chemical changes in the material) than that is visually recognizable. Therefore, a very cautious approach is recommended when performing capsulotomy, as defects in the surface structure can occur. This might come along with problems in quality of vision in monofocal and primarily premium IOLs (multifocal, enhanced depth of focus, and toric IOLs), dependent on the size, dimension, and position in the IOL. YAG capsulotomy should not be considered trivial but should be carried out with precision and without time pressure, just like surgery itself.

Reversibility of the duet procedure: Bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens for correction of a postoperative refractive error

Purpose

We present the case of a 49-year old female who underwent bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens (IOL) to correct a residual refractive error. Six months beforehand, she had been treated for hyperopia, astigmatism and presbyopia with a duet procedure to create reversible trifocality.

Observations

Refractive lens exchange with combined implantation of a monofocal toric IOL into the capsular bag and a trifocal supplementary IOL into the ciliary sulcus (duet procedure) had been performed in both eyes. Decreased uncorrected distance visual acuity due to the refractive outcome of −0.75 diopter sphere (DS)/-0.25 diopter cylinder (DC)x10° for the right eye and −1.0DS for the left eye as well as the perception of photic phenomena were inacceptable for the patient. In the second operations, we exchanged the supplementary IOLs to correct the residual refractive error and achieve the target refraction of emmetropia. UDVA increased from 0.50 logMAR in both eyes prior to the IOL exchange to −0.22 logMAR in the right eye and −0.20 logMAR in the left eye. Binocular uncorrected near and intermediate visual acuity were −0.10 logMAR and 0.00 logMAR respectively after exchanging the sulcus-fixated supplementary IOLs, allowing for complete spectacle independence.

Conclusions

This case demonstrates one of the most important benefits of the duet procedure: the possibility, if necessary, to easily remove or exchange the supplementary IOL from the ciliary sulcus. The duet procedure offers a safe treatment option in the event of postoperative complications like residual refractive error or intolerance to a multifocal optic.

Intraocular Lenses: Overview of Designs, Materials, and Pathophysiologic Features

This article provides an overview of intraocular lenses (IOLs) currently used in cataract surgery. Aspects presented include design features related to IOL construction and sites of fixation; optic, filter, and haptic materials; as well as pathophysiologic features of uveal biocompatibility, capsular biocompatibility, and postoperative IOL opacification. This overview also includes supplementary (add-on; piggyback) lenses implanted in eyes that are already pseudophakic and considerations on IOLs used in the pediatric population. Different IOLs are made available to surgeons each year, including lenses with increasingly complex design characteristics owing to advancements in manufacturing and surgical techniques.

Comparison of glistenings formation and their effect on forward light scatter between the Acrysof SN60WF and Eternity Natural Uni NW-60 intraocular lenses

Aims

To compare the characteristics of glistenings and forward light scatter between the Alcon Acrysof SN60WF and Santen Eternity Natural Uni NW-60 intraocular lenses (IOLs).

Methods

Five Acrysof SN60WF and five Eternity Natural Uni NW-60 IOLs were studied. All IOLs were single piece blue blockers with the same dioptric power (20D) and optic diameter (6.0 mm). Glistenings were induced by a thermal accelerated ageing process. Glistenings were objectively quantified using bespoke image processing software. The angular distribution of forward light scatter was measured using an optical bench system and the straylight parameter calculated from the light scatter function.

Results

The median increase in the number of glistenings was 15 and 525 for the Eternity and Acrysof IOLs, respectively, which was statistically significantly different (p=0.012). Median glistenings diameter was 23.8 μm (Acrysof) and 32.8 μm (Eternity). Four (80%) of the Acrysof lenses had straylight values higher than a 20-year-old CIE standard glare observer and in two cases the straylight exceeded that of the 70-year-old CIE standard glare observer. None of the Eternity lenses had straylight values that exceeded the value for the 20-year-old CIE standard glare observer.

Conclusions

The Eternity Natural Uni NW-60 IOLs resisted the induction of glistenings more than the Acrysof SN60WF IOLs. Although the Acrysof IOLs developed smaller glistenings than the Eternity IOLs, there were sufficient numbers to produce a higher straylight parameter.

Misdiagnosed opacification of a hydrophobic acrylic intraocular lens

A 75-year-old woman was referred for decreased visual acuity resulting from "opacification of the IOL" in the immediate period after uneventful bilateral cataract surgery with single-piece AcrySof IQ intraocular lens (IOL) implantation. A neodymium:YAG laser capsulotomy had been performed in both eyes to treat the complication. Anterior segment optical coherence tomography performed at presentation showed an opaque membrane enveloping the IOL. The membrane was peeled from the anterior IOL surface, and all adherences between the IOL and capsular bag were freed. One year later, the eyes remained stable; the uncorrected distance visual acuity was 20/20, the IOL was clear, and there was no evidence of recurrence of the membrane. Appropriate imaging for the diagnosis and surgical peeling with freeing of the adhesions between the IOL and the capsular bag were essential to the success in this case.

Edge profile of commercially available square-edged intraocular lenses: Part 2

PURPOSE

To analyze the sharpness of the posterior optic edge and edge thickness of intraocular lenses (IOLs) marketed with a square-edged profile.

SETTING

University of Brighton and Brighton and Sussex University Hospitals NHS Trust, Brighton, England.

DESIGN

Laboratory study.

METHODS

Fourteen square-edged 20.0 diopter IOLs were analyzed, including 9 hydrophobic IOLs (AF-1, AF-1 iSert, Clareon, EyeCee One Crystal, CT Lucia, Envista, EyeCee One, Vivinex iSert, and RayOne Hydrophobic) and 5 hydrophilic IOLs (Asphira, CT Asphina, Incise, Synthesis, and RayOne Hydrophilic). All the IOLs were scanned following a previously published standardized technique using environmental scanning electron microscopy. The posterior optic edges were scanned at a magnification of ×500 and ×200 to measure the radius of curvature of the posterior optic edges and the optic edge thickness.

RESULTS

The radius of curvature of the posterior optic edges ranged from 4.6 to 20.6 μm. Except for the Incise IOL (7.7 μm), all hydrophilic IOLs (Synthesis [10.6 μm], Asphira [13.7 μm], RayOne Hydrophilic [14.0 μm], CT Asphina [13.7 μm]) had a radius of curvature greater than 10.0 μm. For the hydrophobic IOLs, the radius of curvature was less than 10.0 μm for the Clareon (7.9 μm), EyeCee One Crystal (4.7 μm), Vivinex iSert (7.6 μm), and CT Lucia (4.6 μm), and greater than 10.0 μm for the Envista (19.7 μm), EyeCee One (13.7 μm), AF-1 iSert (19.7 μm), AF-1 (19.7 μm) and the RayOne Hydrophobic (20.6 μm). The Vivinex iSert (150.5 μm) and the Incise (218.2 μm) were the thinnest IOLs, and the RayOne Hydrophobic (375.8 μm) and RayOne Hydrophilic IOLs (477.1 μm) were the thickest of the hydrophobic and hydrophilic IOLs, respectively.

CONCLUSIONS

Commercially marketed square-edged IOLs still differed in the sharpness of the posterior optic edge. More hydrophobic IOLs have rounder edges than those studied 10 years ago. Variations in the edge profile of hydrophobic IOLs were greater compared with the hydrophilic IOLs.

Surgical experience with a redesigned, fully preloaded, hydrophobic acrylic intraocular lens in challenging cases of pseudoexfoliation syndrome, phacodonesis, and small pupils

Purpose

The purpose of this study was to describe our surgical experience and evaluate safety and postoperative outcomes of a fully preloaded, monofocal, hydrophobic acrylic intraocular lens (IOL) (CT LUCIA 611P) with a newly designed optic-haptic junction in severe cases of pseudoexfoliation (PXF) syndrome, phacodonesis, and small pupils.

Setting

This study was conducted in Borkenstein & Borkenstein, private practice, Privatklinik der Kreuzschwestern Graz, Austria.

Patients and methods

This study presents outcomes of 15 eyes of 15 patients implanted with CT LUCIA 611P IOL with improved optical properties and more rigid and wider optic– haptic junction. All patients had advanced cataract and PXF syndrome, of which phacodonesis was detected in 12 cases and five cases had PXF glaucoma. All eyes had small pupils with no response to mydriatic drops, and the surgery was performed with the use of Malyugin ring. All eyes were targeted for a slight postoperative myopia (−0.25 to −0.50 D). Refractive outcomes were presented for 3 months follow-up, while adverse events were followed up for to 10 months.

Results

The mean age of the study group was 78.3 years (from 68 to 86 years). Three months postoperatively, the mean manifest spherical equivalent was −0.35 D (from 0.00 to −1.00 D) and all eyes were within ±0.50 D of their preoperative target. No significant refractive shift or refractive surprise occurred during the follow-up of 10 months. Corrected distance visual acuity (CDVA) improved from the mean value of 20/50 preoperatively to 20/20 postoperatively. No intraoperative adverse events were noted. Postoperatively, six eyes presented with a slight decentration or tilt, which did not significantly affect postoperative refraction, CDVA, or patients’ subjective visual symptoms.

Conclusion

The IOL provided good surgical performance, excellent refractive stability, and predictable outcomes in patients with PXF syndrome. Further studies are necessary to evaluate long-term stability.

Evaluation of Preloaded IOL Delivery System and Hydrophobic Acrylic Intraocular Lens in Cataract Surgery

Background:

Advancements in cataract surgery have necessitated the availability of intraocular lens preloaded delivery systems that can safely, effectively and predictably deliver IOLs in the eye. Preloaded delivery systems simplify and reduce procedural variability during surgery preparation.

Objective:

The objective of this study was to evaluate clinical acceptability, delivery characteristics and clinical outcomes in patients implanted with new generation hydrophobic acrylic Intraocular Lens with Preloaded delivery system.

Methods:

This was a single centre retrospective study. Total 41 patients were enrolled in the study to get at least 38 patients for evaluation. All patients were assessed on day1 and 1, 3 and 6 months after surgery.

Results:

EYECRYL-SERT showed ‘excellent’ ease of insertion and handling in all 41(100%) patients. Corrected Distance Visual Acuity (CDVA) improved from 0.74±0.58 logMAR during screening to 0.03±0.04 logMAR 6 months after surgery. The Corrected Intermediate Visual Acuity (CIVA) and Corrected Near Visual Acuity (CNVA) were 0.10±0.04 and 0.01±0.02 logMAR post 6 months surgery, respectively. The refractive spherical equivalence was -1.94±2.51 D during screening, which improved significantly (p=0.0018) to -0.21±0.47 D post 6 months surgery. The low and high contrast sensitivity was 0.06±0.06 and -0.05±0.06 logMAR after 6 months surgery, respectively. The endothelial cell loss was 5.67%, 7.22% and 9.75% at 1, 3, and 6 months after surgery, respectively, as compared to screening. None of the subjects reported any adverse event during the study period.

Conclusion:

The IOL delivery system (EYECRYL_SERT) provided desired delivery characteristics during cataract surgery and was effective in improving clinical outcomes in cataract patients.

Biocompatibility of Intraocular Lenses

The performance of an intraocular lens is determined by several factors such as the surgical technique, surgical complications, intraocular lens biomaterial and design, and host reaction to the lens. The factor indicating the biocompatibility of an intraocular lens is the behavior of inflammatory and lens epithelial cells. Hence, the biocompatibility of intraocular lens materials is assessed in terms of uveal biocompatibility, based on the inflammatory foreign-body reaction of the eye against the implant, and in terms of capsular biocompatibility, determined by the relationship of the intraocular lens with residual lens epithelial cells within the capsular bag. Insufficient biocompatibility of intraocular lens materials may result in different clinical entities such as anterior capsule opacification, posterior capsule opacification, and lens epithelial cell ongrowth. Intraocular lenses are increasingly implanted much earlier in life in cases such as refractive lens exchange or pediatric intraocular lens implantation after congenital cataract surgery, and these lenses are expected to exhibit maximum performance for many decades. The materials used in intraocular lens manufacture should, therefore, ensure long-term uveal and capsular biocompatibility. In this article, we review the currently available materials used in the manufacture of intraocular lenses, especially with regard to their uveal and capsular biocompatibility, and discuss efforts to improve the biocompatibility of intraocular lenses.

Killing two birds with one stone: dual blockade of integrin and FGF signaling through targeting syndecan-4 in postoperative capsular opacification

The most common complication after cataract surgery is postoperative capsular opacification, which includes anterior capsular opacification (ACO) and posterior capsular opacification (PCO). Increased adhesion of lens epithelial cells (LECs) to the intraocular lens material surface promotes ACO formation, whereas proliferation and migration of LECs to the posterior capsule lead to the development of PCO. Cell adhesion is mainly mediated by the binding of integrin to extracellular matrix proteins, while cell proliferation and migration are regulated by fibroblast growth factor (FGF). Syndecan-4 (SDC-4) is a co-receptor for both integrin and FGF signaling pathways. Therefore, SDC-4 may be an ideal therapeutic target for the prevention and treatment of postoperative capsular opacification. However, how SDC-4 contributes to FGF-mediated proliferation, migration, and integrin-mediated adhesion of LECs is unclear. Here, we found that downregulation of SDC-4 inhibited FGF signaling through the blockade of ERK1/2 and PI3K/Akt/mTOR activation, thus suppressing cell proliferation and migration. In addition, downregulation of SDC-4 suppressed integrin-mediated cell adhesion through inhibiting focal adhesion kinase (FAK) phosphorylation. Moreover, SDC-4 knockout mice exhibited normal lens morphology, but had significantly reduced capsular opacification after injury. Finally, SDC-4 expression level was increased in the anterior capsule LECs of age-related cataract patients. Taken together, we for the first time characterized the key regulatory role of SDC-4 in FGF and integrin signaling in human LECs, and provided the basis for future pharmacological interventions of capsular opacification.

Physicochemical and surface properties of acrylic intraocular lenses and their clinical significance

To analyze and compare several commercially available acrylic intraocular lenses (IOLs) with particular regard to their clinical significance, we examined the physicochemical and surface properties of four currently available acrylic IOLs using static water contact angle, atomic force microscopy (AFM), Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. The hydrophobic acrylic IOLs, ZA9003, and MA60BM, had contact angles ranging from 77.9° ± 0.65° to 84.4° ± 0.09°. The contact angles in the hydrophilic acrylic (970C) and heparin-surface-modified (HSM) hydrophilic acrylic IOLs (BioVue) were 61.8° ± 0.45° and 69.7° ± 0.76°, respectively. The roughness of the IOL optic surface differed depending on the type of IOL (p < 0.001). The surface roughness of BioVue had the lowest value: 5.87 ± 1.26 nm. This suggests that the BioVue IOL may lead to reduced cellular adhesion compared to the unmodified IOLs. All IOLs including those composed of acrylic optic materials from different manufacturers showed distinct Raman spectra peaks. The glass transition temperatures (T_g) for the hydrophobic acrylic IOLs were between 12.5 and 13.8 °C. These results suggest that the intraoperative and postoperative behavior of an IOL can be predicted. This information is also expected to contribute greatly to the industrial production of reliable biocompatible IOLs.

Surface Modification of Intraocular Lenses

Objective:

This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs).

Data Sources:

All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect.

Study Selection:

The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded.

Results:

Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO₂, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments.

Conclusion:

The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs.

Improvement of Uveal and Capsular Biocompatibility of Hydrophobic Acrylic Intraocular Lens by Surface Grafting with 2-Methacryloyloxyethyl Phosphorylcholine-Methacrylic Acid Copolymer

Biocompatibility of intraocular lens (IOL) is critical to vision reconstruction after cataract surgery. Foldable hydrophobic acrylic IOL is vulnerable to the adhesion of extracellular matrix proteins and cells, leading to increased incidence of postoperative inflammation and capsule opacification. To increase IOL biocompatibility, we synthesized a hydrophilic copolymer P(MPC-MAA) and grafted the copolymer onto the surface of IOL through air plasma treatment. X-ray photoelectron spectroscopy, atomic force microscopy and static water contact angle were used to characterize chemical changes, topography and hydrophilicity of the IOL surface, respectively. Quartz crystal microbalance with dissipation (QCM-D) showed that P(MPC-MAA) modified IOLs were resistant to protein adsorption. Moreover, P(MPC-MAA) modification inhibited adhesion and proliferation of lens epithelial cells (LECs) in vitro. To analyze uveal and capsular biocompatibility in vivo, we implanted the P(MPC-MAA) modified IOLs into rabbits after phacoemulsification. P(MPC-MAA) modification significantly reduced postoperative inflammation and anterior capsule opacification (ACO), and did not affect posterior capsule opacification (PCO). Collectively, our study suggests that surface modification by P(MPC-MAA) can significantly improve uveal and capsular biocompatibility of hydrophobic acrylic IOL, which could potentially benefit patients with blood-aqueous barrier damage.

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

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

Lens status influences the association between CFH polymorphisms and age-related macular degeneration: findings from two population-based studies in Singapore

Aims

To determine the differential effects of genetic polymorphism in CFH and ARMS2 on risk of age-related macular degeneration (AMD) between phakic vs. pseudophakic/aphakic eyes.

Methods

9,529 eyes of 4,918 participants from the Singapore Malay Eye Study and Singapore Indian Eye Study were analyzed. Participants had detailed eye examinations, including slit-lamp examinations and dilated fundus photography. AMD grading was performed according to the Wisconsin age-related maculopathy grading system. Lens status was defined. Single nucleotide polymorphisms (SNPs) rs10801555 (Y402H) within CFH and rs3750847 in ARMS2 were assessed. The main outcome measure was early AMD or any AMD.

Results

No significant associations between the CFH Y402H genotypes and early AMD were found in phakic individuals. In contrast, among pseudophakic/aphakic individuals, the CFH Y402H risk genotypes were significantly associated with higher odds of early AMD, with an OR of 1.57 (95% CI: 1.07–2.29) for GA genotype and 2.40 (95% CI: 1.25–4.61) for AA genotype, compared to those with GG genotype. There was significant interaction between pseudophakic/aphakic status and CFH Y402H variant on risk of early AMD (p = 0.037), adjusting for age, gender, and the first 5 genetic principal components. No significant interaction was found between lens status and ARMS2 rs3750847.

Conclusions

CFH genetic polymorphism and pseudophakic/aphakic status may have a potential synergistic effect on early AMD, suggesting roles for the complement system and related pathways in the pathogenesis of AMD in eyes after cataract surgery.

RGD surface functionalization of the hydrophilic acrylic intraocular lens material to control posterior capsular opacification

Posterior Capsular Opacification (PCO) is the capsule fibrosis developed on implanted IntraOcular Lens (IOL) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing Epithelial Mesenchymal Transition (EMT). Literature has shown that the incidence of PCO is multifactorial including the patient's age or disease, surgical technique, and IOL design and material. Reports comparing hydrophilic and hydrophobic acrylic IOLs have shown that the former has more severe PCO. On the other hand, we have previously demonstrated that the adhesion of LECs is favored on hydrophobic compared to hydrophilic materials. By combining these two facts and contemporary knowledge in PCO development via the EMT pathway, we propose a biomimetically inspired strategy to promote LEC adhesion without de-differentiation to reduce the risk of PCO development. By surface grafting of a cell adhesion molecule (RGD peptide) onto the conventional hydrophilic acrylic IOL material, the surface-functionalized IOL can be used to reconstitute a capsule-LEC-IOL sandwich structure, which has been considered to prevent PCO formation in literature. Our results show that the innovative biomaterial improves LEC adhesion, while also exhibiting similar optical (light transmittance, optical bench) and mechanical (haptic compression force, IOL injection force) properties compared to the starting material. In addition, compared to the hydrophobic IOL material, our bioactive biomaterial exhibits similar abilities in LEC adhesion, morphology maintenance, and EMT biomarker expression, which is the crucial pathway to induce PCO. The in vitro assays suggest that this biomaterial has the potential to reduce the risk factor of PCO development.

Effect of heparin coating of a foldable intraocular lens on inflammation and capsular bag performance after cataract surgery

PURPOSE

To evaluate the effect of a heparin-coated foldable intraocular lens (IOL) on postoperative flare in high-risk patients.

SETTING

Vienna Institute for Research in Ocular Surgery, Department of Ophthalmology, Hanusch Hospital, Vienna, Austria.

DESIGN

Randomized clinical trial.

METHODS

This study included patients with diabetes mellitus (DM), pseudoexfoliation syndrome (PXF), or both scheduled for cataract surgery in both eyes. One eye received a coated IOL (Polylens EC-1YH PAL) and the other eye, an uncoated control IOL (Polylens EC-1Y PAL). Aqueous flare measurements were taken using a laser flare meter (FM-600, Kowa) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively. Visual acuity and anterior (ACO) and posterior (PCO) capsule opacification were assessed, and IOL centration and tilt were measured with a Purkinje meter.

RESULTS

Eighty eyes of 40 patients were included in the study; 64 eyes of 32 patients completed the study. The mean flare values (photons/ms) preoperatively and 1 hour, 1 day, 3 weeks, and 3 months postoperatively were 6.98 ± 3.71 (SD), 19.14 ± 18.90, 16.62 ± 25.33, 10.33 ± 9.70, 8.74 ± 4.64, respectively, with the coated IOL and 8.65 ± 5.73, 22.08 ± 16.23, 13.44 ± 13.71, 7.50 ± 4.11, and 7.03 ± 3.70, respectively, with the control IOL. No significant differences were found in flare, visual acuity, ACO, PCO, tilt, or centration between the coated IOL and the control IOL at any timepoint.

CONCLUSION

No significant differences in flare or capsule performance were found between the coated IOL and control IOL.

Pediatric cataract surgery with hydrophilic acrylic intraocular lens

PURPOSE

To assess the outcomes after hydrophilic acrylic intraocular lens (IOL) implantation during pediatric cataract surgery.

METHODS

This was a retrospective chart review of children who underwent cataract surgery or secondary IOL implantation at Beirut Eye Specialist Centre, Rizk Hospital, between March 2002 and August 2007.

RESULTS

A total of 57 eyes of 40 patients (20 boys) were included in this study. The average age at surgery was 48 ± 40 months (range, 5-172 months). Of these, 54 eyes had congenital or developmental cataracts and 3 eyes had traumatic cataracts. Primary cataract removal and IOL implantation accounted for 45 surgeries, and secondary IOL implantation accounted for 12 surgeries. Hydrophilic acrylic IOLs were implanted in all surgeries. Average follow-up time was 47 ± 21 months (range, 9-97 months). No intraoperative complications were recorded. Of the 57 eyes, 12 (21%) had postoperative complications, but only 7 (12%) required secondary intervention. Average best-corrected visual acuity improved from 2.0 ± 1.0 logMAR preoperatively to 0.8 ± 1.0 logMAR at last follow-up. Improved visual acuity was observed in 47 eyes (82.5%); 31 eyes (54.4%) had a visual acuity of ≥ 20/40 at the last follow-up.

CONCLUSIONS

Hydrophilic acrylic IOLs appear to be suitable for use in pediatric cataract surgery. Results from this study suggest that, compared with hydrophobic IOLs, these IOLs produce similar complication rates, secondary intervention rates, and visual acuity results.

[Early in-the-bag spontaneous intraocular lens dislocation of hydrophilic acryl single piece lenses following uncomplicated phacoemulsification]

BACKGROUND

As techniques for cataract surgery have evolved, spontaneous intraocular lens (IOL) dislocation in patients with no ocular pathology arises less frequently. We present seven consecutive cases of uncomplicated cataract surgery with early in-the-bag spontaneous intraocular lens dislocation for which the same type of hydrophilic single piece lens was used.

MATERIAL AND METHODS

A retrospective analysis was conducted on seven cases involving patients with IOL dislocation who underwent uncomplicated cataract surgery within a period of 4 months (October 2010 to January 2011) using the same type of single piece IOL. The median age of the 7 patients was 73 years and IOL repositioning was performed after an average of 10 weeks.

RESULTS

Sulcus repositioning could be carried out in only five of the seven patients and IOL repositioning within the capsule was achieved in one patient. A second patient exhibited IOL dislocation after yttrium aluminium garnet (YAG) laser capsulotomy. Explantation of the IOL and sulcus implantation of another IOL type (Acrysof MA50 MB) was necessary for a third patient. A fourth case presented an angled IOL haptic and dislocation of the IOL in the sulcus position.

DISCUSSION

Even after uncomplicated cataract surgery, spontaneous in-the-bag IOL dislocation in patients with no ocular pathology may occur due to a hydrophilic lens material which induces stronger anterior capsular phimosis (ACP) in comparison to alternative materials. In combination with a thin lens design this may result in angled IOL haptics and IOL dislocation.

CONCLUSIONS

Careful selection of suitable lens design and material according to individual predisposing factors is necessary. This retrospective case study demonstrates that the combination of hydrophilic lens material and a thin lens design may result in early spontaneous IOL dislocation. Furthermore, as established in one case, YAG laser capsulotomy may induce IOL dislocation if the lens design cannot withstand capsular fibrosis.

Cell adhesion and glistening formation in hybrid copolymer intraocular lenses

The purpose of this study is to investigate the cell adhesion and glistening formation properties of various foldable intraocular lenses (IOLs) in vitro. Three conventional hydrophobic methacrylate acrylic (MA) IOLs, a hydrophilic hydroxyethyl methacrylate (HEMA) IOL and a hybrid MA/HEMA copolymer IOL were investigated for immunologically activated cell adhesion and for formation of glistenings resulting from cavitation, by analysis of digital images using NIH Image J PC software. The MA IOLs exhibited a low level of adhering cells but a high level of glistening formation, the HEMA IOL exhibited the reverse tendency, and the MA/HEMA IOL exhibited a low level of both, thus indicating that hybrid MA/HEMA IOLs are less susceptible than HEMA IOLs to cell adhesion and less susceptible than MA IOLs to glistening formation.

Cataract surgery in uveitis

Cataract surgery in uveitic eyes is often challenging and can result in intraoperative and postoperative complications. Most uveitic patients enjoy good vision despite potentially sight-threatening complications, including cataract development. In those patients who develop cataracts, successful surgery stems from educated patient selection, careful surgical technique, and aggressive preoperative and postoperative control of inflammation. With improved understanding of the disease processes, pre- and perioperative control of inflammation, modern surgical techniques, availability of biocompatible intraocular lens material and design, surgical experience in performing complicated cataract surgeries, and efficient management of postoperative complications have led to much better outcome. Preoperative factors include proper patient selection and counseling and preoperative control of inflammation. Meticulous and careful cataract surgery in uveitic cataract is essential in optimizing the postoperative outcome. Management of postoperative complications, especially inflammation and glaucoma, earlier rather than later, has also contributed to improved outcomes. This manuscript is review of the existing literature and highlights the management pearls in tackling complicated cataract based on medline search of literature and experience of the authors.

Postcataract surgical inflammation

PURPOSE OF REVIEW

To describe the epidemiology, pathogenesis, and recent developments in the diagnosis and management of postcataract surgery inflammation.

RECENT FINDINGS

In patients with pre-existing uveitis, control of inflammation with topical and/or systemic therapy for 3 months preoperatively continues to be important in lessening the risk of postoperative inflammation and complications. During cataract surgery, intraocular lens selection in these patients is important. Recent literature suggests that modern intraocular lenses (IOLs), particularly hydrophilic or hydrophobic acrylic lenses, generally have good uveal biocompatibility in uveitic patients. The postoperative course can be complicated by inflammation and cystoid macular edema (CME), and in uveitic patients, intensive perioperative steroid treatment can lessen these complications. Recent studies show that in uveitic patients, the improvement in CME and inflammation after intravitreal triamcinolone is better than after orbital floor triamcinolone injection, but that a single intraoperative orbital floor injection of triamcinolone is as effective as a 4-week course of postoperative oral prednisolone. Although postoperative inflammation in uveitic patients may be due to recurrence of uveitis, one must recognize other important potential causes of postoperative inflammation and treat accordingly.

SUMMARY

Most patients with postcataract inflammation have good visual outcomes provided that the cause is recognized and that there is adequate perioperative planning in patients predisposed to inflammation.

Pathology of 157 human cadaver eyes with round-edged or modern square-edged silicone intraocular lenses: analyses of capsule bag opacification

PURPOSE

To assess the degree of capsular bag opacification in human cadaver eyes with silicone intraocular lenses (IOLs), specifically comparing the differences between round-edged IOLs and modern square-edged IOLs.

SETTING

John A. Moran Eye Center, University of Utah, USA.

DESIGN

Experimental study.

METHODS

The eyes were immersed in 10% formalin on enucleation. They had anterior segment scanning with a very-high-frequency ultrasound (Artemis). After the eyes were sectioned at the equator, gross examination of the anterior segment was performed from the posterior aspect to assess the degree of capsular bag opacification, coverage of the IOL edge by the anterior capsule, and IOL fixation. Selected eyes also had histopathologic examination.

RESULTS

Eighty-seven eyes with a 3-piece round-edged IOL, 43 with a 3-piece square-edged IOL, 26 with a 1-piece plate IOL, and 1 with an accommodating IOL design were included in the analyses of capsular bag opacification. Comparison between 3-piece round-edged IOLs and square-edged IOLs showed statistically significant differences in central posterior capsule opacification (PCO) (P=.0001687) and peripheral PCO (P<.0001). In eyes with square-edged IOLs, PCO had a tendency to start in areas without capsulorhexis coverage of the optic. Twenty-one of 26 eyes with a silicone plate IOL had a neodymium:YAG posterior capsulotomy for dense PCO.

CONCLUSIONS

This first study using pseudophakic human cadaver eyes that includes a significant number of modern 3-piece silicone IOLs with square optic edges confirmed the role of this design in the prevention of PCO.

FINANCIAL DISCLOSURE

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