Postoperative cellular reaction on various intraocular lens materials

Reversible deposition of inflammatory cells on the surface of an intraocular lens in a patient with uveitis: Case report and literature review

INTRODUCTION

The deposition of inflammatory cells on an intraocular lens (IOL) is a rare but potentially serious complication. We report a patient who presented with reversible severe deposition of inflammatory cells on the anterior surface of a hydrophobic IOL.

CASE DESCRIPTION

A 68-year-old woman with remissive uveitis presented with blurred vision in her right eye that persisted for 1 month. She had undergone cataract surgery and hydrophobic IOL (ZA9003, Johnson & Johnson Surgical Vision) implantation 3 months before presentation. Deposition of inflammatory cells was diagnosed by ocular examination. The IOL became transparent after 6 months of treatment with combined antibiotic/steroid eyedrops (tobramycin/dexamethasone eyedrops) and atropine. However, the cellular deposition recurred after either discontinuing the tobramycin/dexamethasone eyedrops or switching to steroid-only eyedrops (fluorometholone). Therefore, she was prescribed continuous tobramycin/dexamethasone eyedrops, twice-daily, and her IOL remained transparent at the time of submission of this article.

CONCLUSIONS

We have reported a case of reversible severe deposition of inflammatory cells on the anterior surface of a hydrophobic IOL in a patient with uveitis that was managed by continuous administration of combined antibiotic/steroid eyedrops. The morphology of the inflammatory cells deposits and the treatment differed from those of previously reported cases.

Coculture with intraocular lens material-activated macrophages induces an inflammatory phenotype in lens epithelial cells

Cataracts are the leading cause of blindness worldwide, requiring surgical implantation of an intraocular lens. Despite evidence of leukocyte ingress into the postoperative lens, few studies have investigated the leukocyte response to intraocular lens materials. A novel coculture model was developed to examine macrophage activation by hydrophilic acrylic (poly(2-hydroxyethyl methacrylate)) and hydrophobic acrylic (polymethylmethacrylate) commercial intraocular lens. The human monocytic cell line THP-1 was differentiated into macrophages and cocultured with human lens epithelial cell line (HLE-B3) with or without an intraocular lens for one, two, four, or six days. Using flow cytometry and confocal microscopy, expression of the macrophage activation marker CD54 (intercellular adhesion molecule-1) and production of reactive oxygen species via the fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate were examined in macrophages. α-Smooth muscle actin, a transdifferentiation marker, was characterized in lens epithelial cells. The poly(2-hydroxyethyl methacrylate) intraocular lens prevented adhesion but induced significant macrophage activation (p < 0.03) versus control (no intraocular lens), while the polymethylmethacrylate intraocular lens enabled adhesion and multinucleated fusion, but induced no significant activation. Coculture with either intraocular lens increased reactive oxygen species production in macrophages after one day (p < 0.03) and increased expression of α-smooth muscle actin in HLE B-3 after six days, although only poly(2-hydroxyethyl methacrylate) induced a significant difference versus control (p < 0.01). Our results imply that-contrary to prior uveal biocompatibility understanding-macrophage adherence is not necessary for a strong inflammatory response to an intraocular lens, with hydrophilic surfaces inducing higher activation than hydrophobic surfaces. These findings provide a new method of inquiry into uveal biocompatibility, specifically through the quantification of cell-surface markers of leukocyte activation.

Comparison of design of intraocular lens versus the material for PCO prevention

AIM

To evaluate the influence of different intraocular lens(IOL) designs made of PMMA on posterior capsular opacification(PCO) and compare with foldable designs.

METHODS

Phacoemulsification and IOL implantation was done in one eye of 24 New Zealand White rabbits, with IOL of two different designs (Square edged or round edge) and two different materials(PMMA or HEMA). After three months, the animals were sacrificed and enucleated. Evaluation of PCO included posterior view, migration of anterior capsular epithelial cells to the posterior capsule following epithelial-mesenchymal transition were assessed by staining the histological sections of posterior capsule by hematoxylin-eosin(HE) and Periodic acid- Schiff (PAS). The IOLs were extracted and stained with HE to evaluate the presence of adherent cells on the lens surface.

RESULTS

PCO was highest with round edged rigid lens. There was no significant difference in the PCO between the square edged PMMA and square edged foldable lens.

CONCLUSION

It is the design of the IOL not the material that offers protection on PCO formation.

Determination of albumin sorption to intraocular lenses by radiolabeling and confocal laser scanning microscopy

PURPOSE

To determine albumin adsorption profiles and penetration depth of 3 intraocular lens (IOL) materials over time using confocal laser scanning microscopy (CLSM) and radiolabeling.

SETTING

Centre for Contact Lens Research, School of Optometry, and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.

METHODS

Poly(methyl methacrylate) (PMMA), silicone, and foldable hydrophilic acrylic IOLs were incubated in 0.5 mg/mL bovine serum albumin (BSA) for 1, 7, and 14 days. The BSA was conjugated with lucifer yellow VS to allow identification of the protein location by fluorescent imaging with CLSM. Next, the protein uptake was quantified using 2% (125)I-labeled BSA.

RESULTS

Confocal laser scanning microscopy showed increasing BSA uptake for silicone and PMMA IOLs after 14 days of incubation (P<.05), with an apparent penetration depth of 8.7 microm +/- 1.9 (SD) and 9.2 +/- 1.4 microm, respectively. For hydrophilic acrylic IOLs, BSA was detected at a depth of 38 +/- 7.4 microm after 1 day, followed by an increase to 192.7 +/- 16.2 microm after 14 days. Despite the penetration depth into the hydrophilic acrylic IOLs, quantitative results confirmed that PMMA and hydrophilic acrylic deposited significantly less BSA (mean 278.3 +/- 41.7 ng and 296.5 +/- 33.1 ng, respectively) than silicone IOLs (mean 392.6 +/- 37.6 ng) (P<.05).

CONCLUSIONS

Silicone and PMMA IOL materials showed BSA sorption near the lens surface only, while BSA penetrated deep into the hydrophilic acrylic IOL matrix. Combining the qualitative CLSM method and quantitative radiolabeling technique provided detailed information on protein interactions with implantable biomaterials.

Improvement of the surface biocompatibility of silicone intraocular lens by the plasma‐induced tethering of phospholipid moieties

To improve the surface biocompatibility of the silicone intraocular lens (IOL), 2-methacryloyloxyethyl phosphorylcholine (MPC) was tethered onto the IOL through air plasma treatment. Chemical changes on the IOL surface were characterized by X-ray photoelectron spectroscopy (XPS) to confirm the covalent binding of MPC. Morphologies of the IOL surfaces were observed by scanning electron microscopy (SEM) to optimize the plasma treatment process. The hydrophilicity and biocompatibility of the control and modified IOLs were compared by the measurements of water contact angle, platelet adhesion, macrophage cell culture, and lens epithelial cell (LEC) attachment. It was found that, after the tethering of MPC, the hydrophilicity of the IOL can be improved significantly and permanently, and the platelet, macrophage, and LEC adhesion on the IOL surface are obviously suppressed, which indicated the enhancement of surface biocompatibility.

Chemoattraction of inflammatory cells by various intraocular lens materials

PURPOSE

To compare the chemotactic activity induced by polymethyl methacrylate (PMMA), acrylic, and silicone intraocular lens (IOL) materials, regardless of the surgical and host factors.

METHODS

The chemotactic effect of five different IOLs was studied using a modified multi-well Boyden chamber. Two different non-coated PMMA IOLs, a heparin-coated PMMA IOL, an acrylic IOL, and a silicone IOL were assessed. Each mean migration distance of the IOLs was compared with the others using Student's t test.

RESULTS

All IOLs induced some amount of leukocyte chemotaxis. There was no statistically significant difference between the chemotactic activity of PMMA IOLs. However, chemotactic activity was significantly higher in acrylic (p<0.05) and silicone (p<0.05) IOLs compared to one of the PMMA lenses.

CONCLUSIONS

This limited study has proven that chemotaxis assay is a useful tool to assess the biocompatibility of IOLs. The IOL material itself might attract inflammatory cells to its surface in the absence of surgical and host factors. As PMMA IOLs do not cause an increase in inflammatory reaction, they may be considered safe to use. Further improvement in chemical composition and surface characteristics of IOLs should reduce the inflammatory reaction and increase the biocompatibility and safety of IOLs.

Tissue reaction to hydrophilic intraocular lenses

The implant of intraocular lenses (IOLs) following cataract surgery induces a foreign body reaction to the IOL and a lens epithelial cell reaction. The host response to the IOL is mainly influenced by biomaterial properties. With the increasing use of phacoemulsification and small incision cataract surgery, there is growing interest in the use of foldable IOLs made of different materials. Hydrophilic acrylic IOLs include a wide group of foldable biomaterials different in terms of water content. These lenses have been reported to show a good biocompatibility after implantation. Nevertheless, tissue reaction to the implant of hydrophilic lenses is variable and not directly related to the hydrophilicity of their surface. A different adsorption of proteins on the IOL optic surface might be responsible for the different cellular reaction and lens epithelial cell response. Other properties besides hydrophilicity should be taken into account to classify IOL biomaterials.

Surface modification of silicone intraocular implants to inhibit cell proliferation

Photo-cross-linkable polymers bearing cinnamic, sulfonate, and carboxylate groups were synthesized by radical polymerization leading to randomly distributed copolymers. These polymers were used to coat silicone intraocular lenses in order to reduce posterior capsule opacification, also named "secondary cataract". We previously demonstrated that polymers containing both carboxylate and sulfonate groups inhibit cell proliferation, and formulations with the ratio R = COO-/(COO- + SO3-) equal to 0.64 provided the highest inhibitory effect. Ionic polymers with this formulation were synthesized to contain a monomer with pendant siloxane groups in order to get compatibility with the silicone matrix of the intraocular lenses. Anchorage of the ionic polymer at the surface of the silicone implant was achieved by a cycloaddition reaction of the photosensitive groups according to two options. These modified silicone surfaces grafted onto intraocular lenses were shown to inhibit cell proliferation to 60%.

Biological compatibility of polymethyl methacrylate, hydrophilic acrylic and hydrophobic acrylic intraocular lenses

PURPOSE

Extensive clinical investigations of the biocompatibility of different intraocular lenses (IOLs) have been made in an effort to optimize the outcome of modern cataract surgery. The aim of this study was to add animal eye experimental implantation data regarding cellular reaction on the anterior surface of IOLs.

METHODS

Thirteen adult albino rabbits had phacoemulsification/aspiration of the crystalline lens followed by implantation of a posterior chamber IOL in each eye. Three types of IOLs were studied: Hydroview (Bausch and Lomb; n = 7), Acrysof (Alcon, USA; n = 7), and polymethyl methacrylate (PMMA; HOYA, Japan; n = 7). The animals were killed by intravenous pentobarbital 1, 4, or 8 weeks later. The IOLs were explanted and stained with hematoxylin and eosin, and observed under a light microscope. The shape of mouse ascites-induced macrophages on the anterior surface of the three different IOL types (Hydroview, PMMA, and Acrysof) was studied after 24 h of oven culture.

RESULTS

Hydrophilic acrylic IOLs showed the highest affinity for lens epithelial cell (LEC) outgrowth, and the lowest and slowest maturation rate reaction of macrophages. PMMA IOLs showed the lowest affinity for LEC outgrowth, and the highest reaction of macrophages. Hydrophobic acrylic IOLs showed intermediate results both regarding LECs and macrophages.

CONCLUSIONS

Results suggest that IOL biomaterial properties are the key factor that influences the quantity of monocytes/macrophages as well as the process of their maturation/senescence. LEC outgrowth is influenced both by the biomaterial of IOLs and by the monocyte/macrophage reaction.

Inhibitory effects of Arg-Gly-Asp (RGD) peptide on cell attachment and migration in a human lens epithelial cell line

Posterior capsule opacification (PCO) after cataract surgery is caused by growth of residual human lens epithelial (HLE) cells on the posterior capsule. We have shown that extracellular matrix (ECM) is an essential factor for HLE cell attachment and migration. The purpose of this study was to examine the inhibitory effects of Arg-Gly-Asp (RGD) peptide on cell attachment and migration in an HLE cell line. HLE cell line cells (SRA 01/04) that were obtained by transfection of large T antigen of SV40 were cultured in the absence of serum. The culture dishes were coated with type IV collagen, laminin or fibronectin, and Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP) RGD peptide (0.1, 0.3, 1.0, 2.0 mg/ml) was added to the medium. The number of attached cells was counted after 90 min of incubation, and the inhibitory effects of GRGDSP RGD peptide on cell attachment were calculated. Cell attachment on the fibronectin-coated dishes was inhibited by GRGDSP RGD peptide at concentrations higher than 0.3 mg/ml; the inhibitory rate was 80% at a concentration of 2.0 mg/ml. The inhibition of cell attachment by GRGDSP RGD peptide on laminin-coated dishes appeared only at a concentration of 2.0 mg/ml, whereas no effects were observed on the type IV collagen-coated dishes. The inhibitory effects of GRGDSP RGD peptide on cell migration were measured in medium containing 2.0 mg/ml of GRGDSP RGD peptide after 1, 3, 5 and 7 days of culture. Cell migration was inhibited by GRGDSP RGD peptide from 1 day of culture on the fibronectin-coated dishes and from 5 days of culture on the laminin-coated dishes, whereas no effects were observed on the type IV collagen-coated dishes. GRGDSP RGD peptide inhibited cell attachment and migration on laminin and fibronectin that have RGD sequences. These data suggested that RGD peptide may have the potential to prevent PCO.

A 1-year study on carbon, titanium surface-modified intraocular lens in rabbit eyes

PURPOSE

To evaluate biocompatibility of Carbon (C) and Titanum (T) surface modified Polymethyl-methacrylate (PMMA) Intraocular Lens (IOLs) in pseudophakic rabbit model.

METHODS

Extracapsule Cataract Extraction (ECCE) and IOLs implantation were performed in Japanese albino rabbit eyes. The white cell concentration from the aqueous humor in the eyes was counted within 3 months post operation. The inflammatory cells in the eyes were noted and graded by slit lamp using a semiquantitive scale up to 1-year post operation. The rabbit eyes were inspected under light microscopy, where pathology of the eyes was caracterized.

RESULTS

The white cell concentration in the aqueous humor was significantly attenuated in C and T IOL-implanted eyes compared with PMMA IOL-implanted eyes 1 week post operation. The exudate levels in the anterior ocular chamber and the posterior synechias were significant lower in T IOL-implanted eyes than in PMMA IOL-implanted eyes 1 week and 2 weeks after surgery. The exudate levels in the anterior chambers and the posterior synechias were not significantly different in C IOL-implanted versus PMMA IOL-implanted eyes.

CONCLUSIONS

This in vivo study provides evidence of effectiveness of Carbon and Titanium IOLs in improving the biocompatibility of PMMA IOLs.

Relationship between posterior capsule opacification and intraocular lens biocompatibility

The type of healing process that occurs in response to cataract surgery and intraocular lens (IOL) implantation is dependent on a complex set of variables. Their interactions determine whether or not optical clarity is restored as a result of this procedure. In this process, wound healing entails cells undergoing either epithelial-mesenchymal transition, resulting in the generation of fibroblastic cells and accumulation of extracellular matrix, or lenticular structure formation. Such desperate cellular behaviors are regulated by the localized release of different cytokines, including transforming growth factor beta and fibroblast growth factors, which can result in post-operative capsular opacification. Other factors affecting the biological and mechanical outcome of IOL implantation are its composition, surface properties and shape.

Transscleral fixation of foldable intraocular lenses

PURPOSE

To report the results of transscleral implantation of foldable intraocular lenses (IOLs).

SETTING

Department of Ophthalmology Dokuz Eylül University School of Medicine, Izmir, Turkey.

METHODS

Twenty eyes of 20 patients had transscleral fixation of a foldable IOL combined with conventional 3-port pars plana vitrectomy or anterior vitrectomy. Twelve eyes had lens luxation, 8 traumatic and 4 idiopathic. Six eyes were aphakic, 3 after extracapsular cataract extraction and 3 as a result of complicated phacoemulsification. One patient with a mature cataract and pseudoexfoliation had a wide zonular dialysis during phacoemulsification. One patient had an opacified hydrophilic acrylic IOL.

RESULTS

The mean age of the patients was 52.9 years (range 17 to 80 years). The mean preoperative best corrected visual acuity (BCVA) was 20/63 (range counting fingers to 20/25). The mean preoperative refraction was +10.8 diopters (D) (range +10 to +13 D) and the mean preoperative astigmatism, 1.8 D (range 1.0 to 5.5 D). Sixteen IOLs were hydrophobic acrylic, 14 of which were 3-piece AcrySof MA60BM (Alcon) and 2 of which were Sensar AR40 (Allergan). Four IOLs, all VisaAcryl(Staar), were hydrophilic acrylic. The mean power of the IOLs was +22.0 D (range 19.0 to 26.0 D). The mean follow-up was 12 months (range 1 to 18 months). The postoperative BCVA ranged between 20/100 and 20/20, and the mean postoperative astigmatism was 1.1 D (range 0.5 to 4.0 D) at the last follow-up visit. The difference was statistically significant (P<.05). Suture exposure and cystoid macular edema were the only complications, each occurring in 2 eyes.

CONCLUSION

Transscleral fixation of foldable IOLs takes less time and results in fewer complications and better visual outcomes.

Lens epithelial cell reaction after implantation of different intraocular lens materials

PURPOSE

To determine the influence of intraocular lens (IOL) material on anterior capsular opacification and membrane growth over the anterior IOL surface in patients who have undergone standardized small-incision cataract surgery and foldable IOL implantation in the capsular bag.

DESIGN

Randomized controlled trial.

PARTICIPANTS

Eighty-eight cataract patients (88 eyes).

METHODS

Patients were randomly assigned to receive one of four different foldable IOLs after phacoemulsification: Storz Hydroview H60M, Corneal ACR6D, AMO SI40NB, and Alcon AcrySof MA60BM. Examinations on days 7, 30, 90, 180, 360, and 720 after surgery included ophthalmologic examination, slit-lamp biomicroscopy, and photography using red reflex and focal illumination of the anterior IOL surface.

MAIN OUTCOME MEASURES

Best-corrected visual acuity was measured at each examination. In addition, the anterior capsule opacification and the membrane growth on the anterior IOL surface were graded according to a subjective method by the same researcher.

RESULTS

The fibrosis of the anterior capsule was more frequently observed in the group using Corneal ACR6D and AMO SI40NB. The Hydroview and ACR6D groups showed a higher percentage of cases with membrane growth from the rhexis edge on the anterior IOL surface. AcrySof showed the lowest presence of fibrosis of the anterior capsule, and no membrane growth was noted.

CONCLUSIONS

Anterior capsule opacification is an index of IOL biocompatibility. The natural location of lens epithelial cells (LECs) precludes the possibility of the IOL's design influencing the anterior capsule behavior. The local response of LECs varies according to the IOL studied. This may be related to the chemical and physical properties of the materials used in the different IOLs.

Hydrophobic acrylic versus heparin surface-modified polymethylmethacrylate intraocular lens: a biocompatibility study

BACKGROUND

The implant of intraocular lenses (IOLs) following cataract surgery induces a foreign-body reaction to the IOL and a response on the part of the lens epithelial cells (LECs). The purpose of this study was to compare these aspects after the implantation of two different IOL materials.

METHODS

Thirty-six cataract patients were randomised to receive two different foldable lens: an acrylic hydrophobic IOL (Acrysof MA30BA) and a heparin surface-modified (HSM) polymethylmethacrylate IOL (Pharmacia & Upjohn 809C) after phacoemulsification. Slit-lamp biomicroscopy with specular technique was used to assess the inflammatory cell adhesion on the anterior IOL surface, anterior capsule opacification (ACO) and membrane growth from the rhexis edge at 7, 30, 90, 180 and 360 days after surgery.

RESULTS

The 809C group showed a higher percentage of patients with slight inflammatory cell adhesion on the anterior cell surface and a higher small cellular density during the whole follow-up period. The epithelioid cell response was greater in the 809C group than the Acrysof group but the difference between the two groups was not statistically significant. The ACO increased during the follow-up in both groups but was significantly higher in the 809C group.

CONCLUSION

Acrysof lenses are more biocompatible than HSM IOLs, showing a lower grade of inflammatory cell adhesion and ACO. The implantation of these lenses may be particularly indicated in patients with pathologies predisposing to blood-aqueous barrier damage.

Effect of aminoglycosides (sub-MICs) on adherence of coagulase-negative Staphylococci to intraocular lens surface

The authors evaluated the in vitro effects of subinhibitory concentrations (sub-MICs) of aminoglycosides (gentamicin, netilmicin and tobramycin) on the adherence of coagulase-negative staphylococcus to intraocular lens (PMMA, acrylic and heparin) surface. The five strains of coagulase-negative Staphylococcus epidermidis used (S. epidermidis IMe7, IMe11, IMe27, IMe29 and IMe31) were tested for their ability to produce slime. The minimum inhibitory concentrations (MIC) indicated high susceptibility in vitro to the antibiotics and homogeneous values. The adhesion tests without antibiotics (K1, K2 and K3) for every time considered (30 min, 60 min and 180 min) and for all examined strains showed more constant adhesive activity on the surface of acrylic intraocular lens (IOLs) than on the surface of heparin IOLs. The aminoglycosides tested were able to reduce adhesivity by coagulase-negative S. epidermidis slime to the IOL surfaces, even at sub-MICs. The documentation obtained by scanning electron microscope shows the growth of a strain of S. epidermidis IMe11 after 180 minutes of contact which remains adherent to the surface of the acrylic IOLs.

Cell response to AcrySof intraocular lenses in an Indian population

PURPOSE

To evaluate the quantitative cytological response to AcrySof (Alcon) intraocular lenses (IOLs) in an Indian population by studying the incidence, fate, progression, and severity of cell deposits after uneventful phacoemulsification.

SETTING

Iladevi Cataract & IOL Research Center, Ahmedabad, India.

METHOD

This clinical prospective study comprised 64 eyes of 64 healthy patients with senile cataract and no other ocular pathology having phacoemulsification and implantation of an AcrySof IOL. The eyes were observed for cell deposits. One week and 1, 3, 6, 12, and 15 months postoperatively, specular reflex was obtained by slitlamp biomicroscopy under x 20 magnification to record the incidence, progression, morbidity, and severity of small and large (including giant) cells on the IOLs.

RESULTS

The highest incidence of small cells was 18.7%. The cell deposits appeared at 1 week, peaked at 1 month, and were gone after 6 months. The severity was never more than grade 2 (5 to 10 cells). The highest incidence of large cells, including giant cells, was 23.4%. The deposits appeared at 1 month, peaked at 3 months, and were gone after 12 months. The severity was never more than grade 2 (3 to 5 cells). The highest incidence of giant cells was 6.2%. The deposits appeared at 3 months and were gone by 15 months. Severity was never more than grade 1 (2 cells). No IOL had cell deposits at the last follow-up (mean 14 months +/- 3.25 [SD]).

CONCLUSIONS

The incidence, and especially the severity, of cell deposits in the Indian population was low. All cell types, including giant cells, disappeared within 12 months. This could reflect the biocompatibility of the AcrySof IOL and the appropriate surgical technique.

Complications and clinical outcomes of intraocular lens exchange in patients with calcified hydrogel lenses

PURPOSE

To evaluate the outcomes of intraocular lens (IOL) exchange in patients with calcified hydrogel IOLs.

SETTING

Ophthalmology departments of 2 university hospitals in Hong Kong, China.

METHODS

Fifteen patients developed loss of vision resulting from calcification of hydrogel IOLs. The calcified IOLs were explanted and replaced with new IOLs. The best corrected visual acuity before and after surgery was measured and compared.

RESULTS

The mean visual acuity was 0.03 (range 0.01 to 0.20) before IOL exchange and 0.20 (range 0.01 to 0.50) 3 months after; the difference was significant (P <.001). Acuity improved approximately 5 Snellen lines. Complications included posterior capsule rupture in 2 patients and zonular dehiscence in 3 patients; the secondary IOL was placed in the anterior chamber or ciliary sulcus in these patients. Three patients required cutting of the haptics before the calcified IOL could be removed.

CONCLUSION

Intraocular lens exchange was an effective treatment in patients with calcified hydrogel IOLs.

Results of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses in uveitic eyes with cataract: comparison to a control group

PURPOSE

To evaluate the uveal and capsular biocompatibility of hydrophilic acrylic, hydrophobic acrylic, and silicone intraocular lenses (IOLs) in eyes with uveitis.

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This prospective study comprised 72 eyes with uveitis and 68 control eyes having phacoemulsification and IOL implantation by 1 surgeon. Patients received 1 of the following IOLs: foldable hydrophilic acrylic (Hydroview, Bausch & Lomb), hydrophobic acrylic (AcrySof, Alcon), or silicone (CeeOn 911, Pharmacia). Postoperative evaluations were at 1, 3, and 7 days and 1, 3, and 6 months. Cell reaction was evaluated by specular microscopy of the anterior IOL surface and the anterior and posterior capsule reaction, by biomicroscopy.

RESULTS

Small round cell deposition was observed on all IOLs in the immediate postoperative period, especially in eyes with uveitis. This reaction decreased 3 to 6 months after surgery. Although the CeeOn 911 had a higher mean grade of small cells, there was no statistical difference between the 3 IOL types after 6 months in the uveitis and control groups. Foreign-body giant cells (FBGCs) increased after 1 week to 1 month. The AcrySof IOLs had the highest number of FBGCs; after 6 months, there was a statistically significant difference between the AcrySof and Hydroview uveitis groups (P =.036) and the AcrySof and CeeOn 911 uveitis groups (P =.003) but there was no difference among the 3 IOL types in the control group. Lens epithelial cell outgrowth persisted on the Hydroview IOLs in control eyes and regressed on all 3 IOL types in uveitic eyes and on the AcrySof and CeeOn 911 IOLs in control eyes (P =.0001). Anterior capsule opacification (ACO) was more severe on all IOL types in uveitic eyes and on the CeeOn 911 IOL in control eyes. Posterior capsule opacification (PCO) was more severe in uveitic eyes. The Hydroview group had more severe PCO than the AcrySof and the CeeOn 911 groups in uveitis and control eyes. Six months postoperatively, the difference was significant (P =.0001). There was no significant difference between the AcrySof and CeeOn 911 IOLs.

CONCLUSIONS

Intraocular lens biocompatibility is inversely related to inflammation. Hydrophilic acrylic material had good uveal but worse capsular biocompatibility. Hydrophobic acrylic material had lower uveal but better capsular biocompatibility. Silicone showed a higher small cell count (mild) and more severe ACO but achieved PCO results comparable to FBGC results and better than those with the AcrySof lens 6 months after surgery. Despite the differences in IOL biocompatibility, all patients benefited from the surgery.

Uveal and capsular biocompatibility of 2 foldable acrylic intraocular lenses in patients with uveitis or pseudoexfoliation syndrome: comparison to a control group

PURPOSE

To evaluate the uveal and capsular biocompatibility of hydrophilic acrylic (Hydroview) and hydrophobic acrylic (AcrySof) intraocular lenses (IOLs) after phacoemulsification in eyes with pseudoexfoliation syndrome (PEX) or uveitis and compare the results with those in a control group.

SETTING

Department of Ophthalmology, University of Vienna, Vienna, Austria.

METHODS

This prospective nonrandomized comparative trial comprised 143 eyes recruited consecutively. Of these, 49 eyes had PEX, 43 had uveitis, and 51 served as controls. A standardized surgical protocol was used. Cell reaction, anterior (ACO) and posterior (PCO) capsule opacification, and flare were evaluated 1 year after cataract surgery.

RESULTS

Regarding uveal biocompatibility, the number of foreign-body giant cells (FBGCs) increased in proportion to associated ocular pathologies in both IOL groups. The difference between the Hydroview control and Hydroview uveitis groups was statistically significant. The number of FBGCs was greater on AcrySof IOLs than on Hydroview IOLs in all 3 groups. The difference in FBGCs between the 2 IOL types was statistically significant in the control and PEX groups. Regarding capsular biocompatibility, lens epithelial cell (LEC) outgrowth was inversely correlated with intraocular inflammation. Outgrowth was statistically significantly higher with Hydroview IOLs, occurring in 85% in the control group, 45% in the PEX group, and 28% in the uveitis group (P <.0001). With AcrySof lenses, the percentages were 0%, 8%, and 4%, respectively. The PEX and uveitis groups were more likely to develop ACO than the control group (P <.012). There was no statistically significant difference in ACO between the 2 IOL types in the 3 patient groups. The PCO was statistically significantly greater in the uveitis group than in the control group (P <.026) and statistically significantly more dense on Hydroview than on AcrySof IOLs in all 3 patient groups (P <.002). Flare was statistically significantly higher in the uveitis group than in the PEX and control groups with both IOL types (P <.012). There was no statistically significant difference in flare between the 2 IOL types.

CONCLUSIONS

Uveal and capsular biocompatibility depends on the intensity of ocular inflammation. The greater the inflammation, the less the biocompatibility of hydrophilic and hydrophobic acrylic materials. AcrySof stimulated more FBGCs. The Hydroview material had better uveal but poorer capsular biocompatibility than AcrySof. The sharp optic edge effect of the AcrySof IOL and the advantages of the Hydroview lens in normal eyes are less apparent in compromised eyes.

Biocompatibility of hydrophilic intraocular lenses

PURPOSE

To assess the biocompatibility of 3 hydrophilic acrylic intraocular lenses (IOLs) by evaluating the postoperative cell reaction on the IOL surface, anterior capsule opacification (ACO) rate, and presence of membrane growth over the anterior IOL surface.

SETTING

University Eye Clinic of Trieste, Trieste, Italy.

METHODS

In this prospective study, 73 patients were randomized to receive 1 of 3 types of hydrogel IOLs after phacoemulsification: Storz Hydroview H60M, Corneal ACR6D, or Ioltech Stabibag. To analyze and photograph the anterior IOL surface, slitlamp biomicroscopy and specular microscopy were performed 7, 30, 90, and 180 days after surgery. Small, epithelioid, and giant inflammatory cell reaction was evaluated. In addition, ACO and membrane growth on the anterior IOL surface were assessed.

RESULTS

Low inflammatory cell adhesion was observed on the anterior surface of all 3 IOLs. The Stabibag group had a significantly higher grade of small inflammatory cell reaction 7 and 30 days after surgery. A significantly higher rate of ACO was observed in the ACR6D group. The Hydroview and ACR6D groups had a significantly higher percentage of membrane growth from the capsulorhexis edge onto the anterior IOL surface than the Stabibag group.

CONCLUSIONS

Clinically, the 3 hydrophilic IOLs behaved in a different manner, showing the different forms of biocompatibility. Results indicate that a different chemical composition determines correspondingly different protein absorption on IOL surfaces. This might result in a different adhesion pattern and spreading of lens epithelial and inflammatory cells.

Implantation and capsular bag stability of single-piece, foldable EasAcryl 1 intraocular lenses

PURPOSE

To assess the folding and implantation of the single-piece EasAcryl 1 intraocular lens (IOL) and the maintenance of the tunnel structure and capsular bag stability after implantation.

SETTING

S. Orsola Hospital Department of Pathophysiologic Optics, University of Bologna, Bologna, Italy.

METHODS

This study comprised 300 cases of EasAcryl 1 IOL implantation. First, a 3.2 mm corneal incision was made according to preoperative astigmatism followed by a 5.5 mm +/- 0.3 (SD) capsulorhexis. After sutureless phacoemulsification using a venturi pump, the 6.0 mm optic, 11.0 mm diameter IOL was implanted using a hexagonal cartridge. The IOLs were implanted using a 2-step maneuver when the superior haptic was grasped with the forceps (first case) or a 1-step maneuver when only the Microsert injector was used. The cartridge was never pushed beyond the tunnel. The preoperative and postoperative incision size and the corneal surgically induced astigmatism were recorded. The IOL rotation was measured 30 +/- 5 days and 8 +/- 1 months postoperatively.

RESULTS

No intraoperative complications occurred after the learning curve. No alteration in astigmatism was observed. The mean IOL rotation was 1.04 +/- 0.5 degrees at 30 +/- 5 days and 1.02 +/- 0.2 degrees at 8 +/- 1 months.

CONCLUSIONS

The EasAcryl 1 was easily implantation through a 3.2 mm tunnel without altering the natural architecture. The unfolding of the IOL was well controlled, and the IOL remained well centered. A short learning curve is required.

Comparison of long-term incidence of posterior capsular opacification between phacoemulsification and phacotrabeculectomy

PURPOSE

To investigate the long-term incidence of posterior capsular opacification after phacoemulsification compared with phacotrabeculectomy with or without adjunctive subconjunctival mitomycin C.

METHODS

This was a retrospectively conducted long-term, observational, case-control study. One hundred eyes of 100 cataract patients who underwent phacoemulsification and posterior chamber intraocular lens implantation and 100 eyes of 100 primary open-angle glaucoma patients with cataract that underwent phacotrabeculectomy and posterior chamber intraocular lens implantation, matched with respect to age, intraocular lens type, prevalence of diabetes mellitus, and length of follow-up. The main outcome measure was the rate of clinically significant posterior capsular opacification as determined by slit-lamp biomicroscopy and necessity to perform neodynium:yttrium aluminum garnet (Nd:YAG) capsulotomy and as calculated by Kaplan-Meier survival analysis. Postoperative visual acuity and maintenance of intraocular pressure control were also measured.

RESULTS

There was no significant difference in the rate of posterior capsular opacification requiring Nd:YAG capsulotomy between the phacoemulsification and phacotrabeculectomy groups (P =.77). However, a significant difference in the rate of posterior capsular opacification was found between those patients without diabetes mellitus and those with a preoperative diagnosis of diabetes mellitus (P =.016). Also, survival analysis comparing use of mitomycin C with no use of mitomycin C in the phacotrabeculectomy group showed a higher survival in the mitomycin C subgroup (P =.03).

CONCLUSION

There was no significant difference in long-term posterior capsular opacification between phacoemulsification and phacotrabeculectomy in the study population. Intraoperative, adjunctive use of mitomycin C in the phacotrabeculectomy group and the presence of diabetes mellitus in the overall patients were beneficial (protective) factors against posterior capsular opacification.

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

PURPOSE

To evaluate the long-term response of 6 types of 3-piece intraocular lenses (IOLs) by assessing the cellular reaction on the anterior IOL surface, the behavior of posterior and anterior capsule fibrosis, and flare.

SETTING

Department of Ophthalmology, Medical School, University of Vienna, Vienna, Austria.

METHODS

One hundred eighty eyes were prospectively randomized to receive 1 of 6 IOLs: hydrophilic acrylic Hydroview (Bausch & Lomb) or MemoryLens (ORC); hydrophobic acrylic AcrySof MA60BM (Alcon) or AMO Sensar AR40 (Allergan); hydrophobic silicone CeeOn 920 or CeeOn 911A (Pharmacia). The patients had standardized cataract surgery, postoperative medication, and follow-up. One year after surgery, 155 eyes were assessed. The cellular reaction was evaluated by specular microscopy of the anterior IOL surface. Anterior and posterior capsule opacification (PCO) was assessed semiquantitatively by biomicroscopy. Flare was measured with a Kowa FC-1000 laser flare-cell meter.

RESULTS

Regarding uveal biocompatibility, the hydrophobic acrylic IOLs showed the highest incidence of late foreign-body cell reaction (AcrySof, 30%; AR40, 17%) followed by the hydrophilic acrylic (MemoryLens, 8%; Hydroview, 4%) and silicone (CeeOn 920, 4%; CeeOn 911A, 0%) (P =.0044). In all cases, the cellular reaction was low grade and clinically insignificant. Regarding capsular biocompatibility, some eyes developed lens epithelial cell (LEC) outgrowth on the anterior IOL surface. The highest incidence was in the hydrophilic acrylic group (Hydroview, 85%; MemoryLens, 27%) followed by the hydrophobic acrylic (AcrySof, 4%; AR40, 3%). No silicone IOL had LECs on the anterior surface. The difference among IOL groups was significant (P =.0001). Anterior capsule opacification was more predominant in the hydrophobic IOL groups. Posterior capsule opacification of the central 3.0 mm area was lowest in the groups with a sharp-edged optic (CeeOn 911A, AcrySof) followed by the round-edged silicone (CeeOn 920), hydrophobic acrylic (AR40), and hydrophilic acrylic IOLs (P =.0001). There was a significant difference in flare between the AR40 lens and the Hydroview, MemoryLens, CeeOn 911A, and CeeOn 920 (P <.004). There was no statistically significant difference in the postoperative cell count at 1 year. The power calculation showed that the sample size was sufficient.

CONCLUSIONS

The differences in cellular reaction, although clinically mild in normal eyes, indicate that there were more giant cells with hydrophobic acrylic IOLs and an increased tendency toward LEC outgrowth with hydrophilic lenses. The incidence of PCO was lowest in the hydrophobic IOL groups, especially in groups with a sharp-edged optic. Second-generation silicone IOLs with a sharp edge had good uveal and capsular biocompatibility 1 year after surgery.

Evaluation of cellular adhesions on silicone and poly(methyl methacrylate) intraocular lenses in monkey eyes: an electron microscopic study

PURPOSE

To assess the biocompatibility of intraocular lens (IOL) material by studying the number of cells adhering to IOLs in monkey eyes.

SETTING

Department of Ophthalmology, Kyushu University, Fukuoka, Japan.

METHODS

Silicone or poly(methyl methacrylate) (PMMA) IOL implantation was performed in 21 monkeys. One eye of each animal had surgery. The IOL-implanted eyes were enucleated 1, 2, 3, 5, and 7 days and 1, 3, 4, 5, and 9 months after the procedure. One eye was studied at each time. Cells on the anterior IOL surface were photographed using a scanning electron microscope, counted and assessed with NEC, Graphtec, and Nikon equipment, and then observed using a transmission electron microscope.

RESULTS

Leukocytes, macrophages, and giant cells were found on the anterior IOL surface. Numerous cells were observed on the PMMA IOLs in the early postoperative period; they gradually decreased. Few cells were seen on the silicone IOLs during the course of the study. The giant cells became larger during the postoperative period.

CONCLUSION

The foreign-body reaction to silicone IOLs in monkey eyes was less than that to PMMA IOLs.

Membranous proliferation of lens epithelial cells on acrylic, silicone, and poly(methyl methacrylate) lenses

PURPOSE

To determine whether intraocular lens (IOL) material influences the membranous proliferation of lens epithelial cells (LECs) on the anterior surface of the IOL.

SETTING

Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

METHODS

This prospective study included 87 eyes of 87 consecutive patients who had cataract surgery with IOL implantation. Patients were randomly assigned to receive a single-piece poly(methyl methacrylate) (PMMA) IOL, a 3-piece silicone IOL, or a 3-piece acrylic IOL. Postoperatively, the IOL optic was examined by slitlamp microscopy at 1 and 10 days and 1, 2, and 3 months to determine the incidence, duration, and extent of membranous LEC proliferation. The optic was also examined at 6, 9, and 12 months if proliferation persisted.

RESULTS

Thirteen eyes were excluded from analysis because of incomplete coverage of the IOL rim by the anterior capsule margin; 74 remaining eyes were studied. All patients obtained good postoperative visual acuity (20/25 or better). Incidence (P =.0024) and duration (P =.0002) of membranous LEC proliferation with the acrylic IOL was greater than with the other 2 types. Proliferation on the acrylic IOL was more extensive than on the PMMA IOL 10 days postoperatively (P <.05) and on the silicone IOL at 10 days (P <.01) and 1 month (P <.01). However, LEC proliferation on the 3 types of IOLs usually decreased by the third postoperative month, and proliferation did not disturb visual acuity.

CONCLUSIONS

The material of an IOL influenced membranous proliferation of LECs on its anterior surface. Proliferation on the acrylic IOL persisted longer than on the other 2 types but did not cause visual symptoms.

Clinical features of 46 eyes with calcified hydrogel intraocular lenses

PURPOSE

To clarify the clinical features of delayed calcification of hydrogel intraocular lenses (IOLs) based on observation of a large case series.

SETTING

Ophthalmology department of 2 university teaching hospitals, Hong Kong, China.

METHODS

The first 44 patients with a known diagnosis of calcified IOL were recruited. Medical and ophthalmic histories were obtained. Surgical details, surgical complications, and visual acuity before and after IOL implantation were also retrieved. Patients then had a visual acuity test, a slitlamp examination of the features of the IOL calcification, and a fundus examination for clarity of view.

RESULTS

Forty-six eyes of 44 patients had IOL calcification. All had a Hydroview IOL. The onset was from 4 to 26 months after surgery. Ninety-three percent of eyes had generalized IOL calcification, and 96% had forceps marks on the IOL. Mean visual acuity deteriorated from 0.4 at 3 months to 0.13 at 19 months. Visual loss was more severe in patients with diabetes mellitus or ischemic heart disease and in those in which the IOL calcified earlier after implantation.

CONCLUSION

All cases of IOL calcification were delayed in onset. The presence of forceps marks may provide a clue to the pathogenesis. Bilateral but asymmetric involvement in 2 patients suggests that the IOL was involved in the pathogenesis. Affected patients lost an average of 2.8 Snellen lines of visual acuity. Some eyes progressed more rapidly; however, the modulating factors remain unknown.

Cellular reaction on the anterior surface of 4 types of intraocular lenses

PURPOSE

To assess the cellular reaction on the anterior surface of 4 types of foldable intraocular lenses (IOLs).

SETTING

Department of Ophthalmology, University Hospital of Vienna, Vienna, Austria.

METHODS

One hundred eyes scheduled for cataract surgery were prospectively randomized into 4 groups of 25 eyes each using random number tables. Group 1 received a Hydroview IOL (Bausch & Lomb), Group 2 an AcrySof IOL (Alcon), Group 3 a MemoryLens IOL (ORC), and Group 4 a CeeOn 920 IOL (Pharmacia). Patients were examined 1, 3, 7, 30, 90, and 180 days postoperatively. Postoperative biomicroscopic examinations were done with a slitlamp, and a specular microscope was used to document the presence of cell deposits and identify areas with the highest density of cells.

RESULTS

The local tissue response revealed 2 patterns: a nonspecific foreign-body reaction to the IOL (small round, fibroblast-like, epithelioid, and giant cells) and a lens epithelial cell (LEC) reaction. The highest incidence of LECs was in the Hydroview group, in which LECs were present on 81.8% of lenses 180 days postoperatively. During the first postoperative days, small round and fibroblast-like cells were found on all IOLs. From 7 days on, the incidence and density of these cells were less severe in the Hydroview and CeeOn 920 groups. After several weeks, epithelioid cells and foreign-body giant cells were seen on some IOLs. These cells appeared more often on AcrySof, MemoryLens, and CeeOn IOLs.

CONCLUSION

This study found IOL-related differences in cellular reaction after cataract surgery. The incidence of a nonspecific foreign-body reaction to 4 IOLs is consistent with the results of previous studies. The incidence of LECs was highest in the Hydroview group and lowest in the AcrySof group. The CeeOn 920 group had the lowest incidence of all types of cells.

Inflammatory cell adhesion and surface defects on heparin-surface-modified poly(methyl methacrylate) intraocular lenses in diabetic patients

PURPOSE

To evaluate the incidence of surface scratches on heparin-surface-modified (HSM) poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) and the possible influence of these alterations on the biocompatibility of HSM PMMA.

SETTING

University Eye Clinic of Trieste, Trieste, Italy.

METHODS

Twenty-six diabetic patients had phacoemulsification and implantation of an HSM PMMA IOL (809C, Pharmacia & Upjohn). Patients with proliferative diabetic retinopathy or iridopathy were excluded from the study. On postoperative days 7, 30, 90, and 180, specular microscopy was performed to study and photograph the anterior IOL surface. The presence of scratches on the anterior IOL surface was assessed and the inflammatory cell reaction noted and graded using a semiquantitative scale. Finally, the location of the inflammatory cells in relation to the surface scratches was established.

RESULTS

Scratches and other surface defects were found in 88.4% of cases. All patients had small cells on the IOL surface 7 days after surgery. At 30 days, small cells were observed in 88.4% of cases. The inflammatory cells were mainly located inside the scratches rather than throughout the IOL surface.

CONCLUSIONS

This in vivo cytology study provides further evidence of the effectiveness of heparin surface modification in improving the biocompatibility of PMMA. In diabetic patients, inflammatory cells adhered to the exposed PMMA surface more than to the HSM surface, suggesting that the use of HSM PMMA in patients with conditions predisposing them to increased postoperative blood-aqueous barrier breakdown is beneficial.

Pit defects on the anterior surface of hydrophilic foldable intraocular lenses

A series of pits varying in depth and size appeared on the anterior surface of hydrogel intraocular lenses (IOLs) soon after they were implanted. In all cases, the pits increased in size but not in number during a 1 year follow-up. The origin of the pit defects is unknown and does not seem related to inflammatory or lens epithelial cell activity. Hydration of the IOL could be a cause even if a manufacturing defect were present. This IOL surface alteration did not seem to impair visual function or cause visual disturbances.

Posterior capsular opacification in phacotrabeculectomy : a long-term comparative study of silicone versus acrylic intraocular lens

PURPOSE

To investigate the long-term outcomes of silicone versus acrylic intraocular lens (IOL) implantation in phacotrabeculectomy (PT) with special emphasis on posterior capsular opacification.

DESIGN

Long-term follow-up on prior 1-year prospective, randomized study.

PARTICIPANTS

A total of 200 eyes of 200 consecutive primary open-angle glaucoma patients who had undergone primary PT with capsular bag implantation of either a silicone IOL (102 eyes) or an acrylic IOL (98 eyes) according to the initial short-term prospective, randomized study protocol.

INTERVENTION

The study eyes underwent primary trabeculectomy, phacoemulsification, and posterior chamber IOL implantation. Adjunctive mitomycin C was used selectively, primarily in patients with one or more risk factors for filtration failure.

MAIN OUTCOME MEASURES

Incidence of posterior capsular opacification (PCO), best-corrected visual acuity (BCVA), intraocular pressure (IOP), number of pressure-lowering medications, and filtration success rates, defined as maintenance of target IOP while on one (criteria 1) or zero (criteria 2) pressure-lowering medications without further surgical intervention.

RESULTS

At 3-year follow-up, the PCO rate and BCVA did not differ significantly between the two groups (P: > 0.05 for both). In addition, there were no significant differences in IOP, number of medications, and filtration success rate between the two groups (P: > 0.05 for each).

CONCLUSIONS

There were no significant long-term differences between the silicone and acrylic IOL groups in PCO, BCVA, IOP, number of medications, and success of filtration surgery after PT. Both groups attained significant improvement in BCVA and IOP control after surgery.

Effect of heparin-surface-modified intraocular lenses on postoperative inflammation after phacoemulsification: a randomized trial in a United States patient population. Heparin-Surface-Modified Lens Study Group

OBJECTIVE

To compare postoperative inflammation occurring with heparin-surface-modified (HSM) versus non-HSM polymethyl methacrylate intraocular lenses (IOLs) after phacoemulsification.

DESIGN

Randomized, double-masked, multicenter, parallel trial.

PARTICIPANTS

A total of 367 patients, consisting of routine (n = 220), glaucoma (n = 58), and diabetes (n = 89) patients, from eight US medical centers.

METHODS

Patients were observed for 1 year after phacoemulsification and lens implantation (week 1, months 1, 3, 6, 12).

MAIN OUTCOME MEASURES

Primary measures of postoperative inflammation defined as the presence of giant cells on the lens surface via specular micrography and cellular deposits via slit-lamp examination.

RESULTS

The cross-sectional analyses showed that consistently fewer routine patients with HSM lens implants had giant cells on the IOL than those with non-HSM lens implants across all follow-up visits. The statistical significance (P < 0.05) was observed at all visits except month 12 for routine patients. The diabetes patients also demonstrated the same giant cell difference, and the statistical significance was observed at all visits including month 12. A similar trend was also observed in the glaucoma patients, with statistical significance only at the 3-month visit. For cell deposits, significant differences in favor of the HSM lens (P < 0.05) were observed at 3 months among routine and diabetes patients, and at 3 and 6 months among glaucoma patients. A longitudinal data analysis using the generalized estimating equation approach indicated statistically significant treatment effect of HSM lenses in reducing inflammation in all patients except for cellular deposits in diabetes patients. In all patient groups, sight-threatening complications were not reported either more frequently or with more severity than normally expected for patients who have undergone cataract extraction and IOL implantation.

CONCLUSIONS

The present study, the only one to have used phacoemulsification in virtually all patients (211/220 [96%] routine, 57/58 [98%] glaucoma, and 84/89 [94%] diabetes) is the largest to evaluate and compare concurrently routine, glaucoma, and diabetes patients. It is also the first US patient population study to document that heparin surface modification reduces postoperative inflammatory responses, as measured by specular micrography and slit-lamp examination, especially in the early postoperative period.

Evaluation of giant-cell deposits on foldable intraocular lenses after combined cataract and glaucoma surgery

PURPOSE

To compare the incidence of inflammatory giant-cell deposits (IGCDs) on various foldable intraocular lenses (IOLs) after combined cataract and glaucoma surgery.

SETTING

The Phillips Eye Institute, Minneapolis, Minnesota, USA.

METHODS

In this prospective randomized clinical trial, 128 patients were randomized to receive a single-piece, first-generation silicone lens (n = 36); a 3-piece acrylic lens (n = 40); or 3-piece, second-generation silicone lens (n = 52). All patients had combined phacoemulsification and trabeculectomy with mitomycin-C by 1 surgeon using a standardized technique. Dilated biomicroscopy was used to identify and quantitate IGCDs on the surface of the IOLs using a 6-point grading scale.

RESULTS

Inflammatory giant-cell deposits were identified on 21 of 128 IOLs. Lens design was the most significant risk factor for deposit formation (P =.004). Inflammatory giant-cell deposits were most common in the first-generation silicone plate lens group (33%), less common in the acrylic lens group (15%), and least common in the 3-piece, second-generation silicone group (5.8%). Density of the deposits was significantly greater on the plate lens than the acrylic or the 3-piece silicone lenses (P <.0001). Although IOL design was the most significant risk factor for IGCD formation, other significant risk factors included intraoperative pupil stretch (P =.02) and preoperative miotic use (P =.04).

CONCLUSION

Inflammatory giant-cell deposit formation was significantly greater on first-generation silicone plate IOLs than on acrylic or second-generation silicone IOLs. The deposits were somewhat more common on acrylic IOLs than on second-generation silicone IOLs. However, this difference was not clinically or statistically significant.

Posterior capsular opacification with hydrogel, polymethylmethacrylate, and silicone intraocular lenses: two-year results of a randomized prospective trial

PURPOSE

To compare the visual outcome, percentage of posterior capsular opacification, and laser capsulotomy rates with polymethylmethacrylate, silicone, and hydrogel intraocular lens implants at 1 and 2 years postoperatively.

METHODS

Ninety-three eyes of 93 patients were randomized to receive a polymethylmethacrylate, silicone, or hydrogel intraocular lens implant. A standardized surgical protocol was followed by a single surgeon using phacoemulsification with capsulorhexis; any patients with surgical complications were excluded, and all patients received standardized medication and follow-up. Patients were examined at days 1 and 7, months 1, 3, and 6, and years 1 and 2 after surgery. At each assessment, best-corrected logMAR visual acuity and Pelli-Robson contrast sensitivity were measured. Posterior capsular opacification was objectively assessed by digital retroillumination imaging with the use of a dedicated software program and calculated as the percentage area of opacified capsule. Laser capsulotomy was performed if the eye had lost 2 lines of visual acuity with a clinically opaque capsule.

RESULTS

At 2 years postoperatively, the mean percentage area of posterior capsular opacification for hydrogel lenses was 63%; for polymethylmethacrylate, 46%; and for silicone, 17%. Hydrogel intraocular lenses were associated with 17% more posterior capsule opacification than were polymethylmethacrylate lenses (95% confidence interval, 1-33; P =. 037) and 45% more than were silicone lenses (95% confidence interval, 33-58; P <.0001) at 2 years. Polymethylmethacrylate lenses had 28% more posterior capsule opacification than silicone lenses (95% confidence interval, 13-43; P <.0001) at 2 years. Twenty-eight percent of patients with hydrogel intraocular lenses required an Nd:YAG laser posterior capsulotomy at 2 years, compared with 14% with polymethylmethacrylate, whereas no patients with silicone lenses needed a capsulotomy (P =.014). Visual acuity was not significantly different among the three groups, but patients with silicone intraocular lenses had significantly better contrast sensitivity than those with hydrogel lenses (P =.046).

CONCLUSIONS

Intraocular lenses made of this specific hydrogel were associated with a significantly higher degree of posterior capsular opacification and more laser capsulotomies than polymethylmethacrylate and silicone intraocular lenses.

Evaluation of foldable intraocular lenses in patients with uveitis

OBJECTIVE

To evaluate various foldable posterior chamber intraocular lenses (IOLs) after phacoemulsification in patients with uveitis.

DESIGN

A prospective, noncomparative, interventional case series.

PARTICIPANTS

Forty-nine consecutive patients (60 eyes) with various types of uveitis (anterior, n = 20; posterior, n = 1; panuveitis, n = 37, intermediate, n = 2).

INTERVENTION

All patients underwent phacoemulsification with foldable posterior chamber IOL implantation. All eyes were free of active inflammation at the time of surgery. A variety of IOL biomaterials were implanted: acrylic (n = 30), silicone (n = 17), and hydrogel (n = 13).

MAIN OUTCOME MEASURES

Detailed examination was performed by one masked observer. Several parameters were compared for each implant biomaterial, including level of best corrected Snellen visual acuity at final follow-up, presence of posterior synechiae, anterior capsular phimosis, posterior capsule opacification, and the degree of cellular deposits on the IOL optic.

RESULTS

There were 26 males and 23 females, aged 9 to 83 years (mean, 48 years). Follow-up ranged from 1 to 33 months (mean, 17.03 months). At final follow-up, 56 eyes (93.3%) had an improvement in visual acuity compared with preoperative levels as follows: 34 eyes (56.6%) achieved an improvement of four or more Snellen lines, and 44 eyes (73.3%) achieved 20/30 or better. Giant cells, observed on the IOL optic in 19 eyes (31.7%), were most often seen on the acrylic biomaterial at the 1-month follow-up, although this was not found to be statistically significant. Scratch marks produced by the lens-introducing forceps were seen in 24 eyes (40.0%), mainly on the acrylic and hydrogel optics. Posterior capsule opacification (PCO) occurred in 49 eyes (81.7%), with only 5 eyes requiring laser capsulotomy. There was no association between PCO and the various lens biomaterials. Other causes for reduced visual acuity included glaucomatous optic neuropathy (n = 5) and cystoid macular edema (n = 8).

CONCLUSIONS

The use of foldable IOLs in eyes with uveitis is safe, but the optimal biomaterial has yet to be found.

Two year results: sharp versus rounded optic edges on silicone lenses

To evaluate the role of optic edge design of 2 silicone intraocular lenses (IOLs) in 2 year clinical results. Department of Ophthalmology, University of Vienna, Medical School, Allgemeines Krankenhaus, Austria. In this comparative clinical study, 50 eyes had phacoemulsification and implantation of a high-refractive 3-piece silicone IOL with sharp optic edges (CeeOn model 911F) (n = 25) or a 3-piece silicone lens with rounded optic edges (CeeOn model 920) (n = 25). Biomicroscopic findings, including those of specular microscopic examination of the anterior lens surface, were documented and the results analyzed. After 2 years, a significant between-group difference in posterior capsule opacification (PCO) but not in anterior capsule alterations was observed. Behind all CeeOn 911F sharp-edge IOLs, the capsule remained clear; in 2 of 23 capsules behind the CeeOn 920 rounded-edge, a neodymium: YAG laser capsulotomy had to be performed for dense central fibrotic PCO. Seven of 21 of the remaining eyes had first-degree central fibrotic PCO, 14 of 23 had peripheral mixed fibrotic and slender Elschnig pearl PCO, and 8 of 23 had second-degree peripheral PCO. Specular microscopic findings did not differ between the 2 groups. No severe IOL decentration occurred in any eye; 25% in the sharp-edge group and 40% in the rounded-edge group had minimal decentration. The silicone IOL with the sharp optic edge design was associated with significantly reduced PCO 2 years postoperatively.

Incidence of anterior intraocular lens precipitates after combined phacotrabeculectomy

PURPOSE

To compare the incidence of anterior intraocular lens (IOL) precipitates on silicone and poly(methyl methacrylate) (PMMA) IOLs after phacotrabeculetomy.

SETTING

District general hospital in the United Kingdom.

METHODS

Ninety-five consecutive eyes of 77 patients who had combined phacotrabeculectomy between April 1992 and October 1996 were retrospectively studied. A slitlamp biomicroscope was used to look for precipitates.

RESULTS

Mean patient age was 75 years (range 51 to 89 years). Preoperatively, mean intraocular pressure (IOP) was 26 mm Hg +/- 5.26 (SD). Thirty plate-haptic silicone IOLs and 65 PMMA IOLs were implanted. Six months postoperatively, median corrected Snellen acuity improved from 6/18 to 6/9. The mean number of antiglaucoma medications dropped from 1.46 preoperatively to 0.29 postoperatively; 73 eyes (76.8%) had an IOP of less than 22 mm Hg with no medication. In 1 surgeon's experience, lens precipitates appeared in 10 of 59 cases (16.9%), with 7 of 14 (50.0%) in the silicone IOL group and 3 of 45 (6.7%) in the PMMA IOL group. The difference was statistically significant (P <.001, chi-square).

CONCLUSION

The incidence of anterior IOL precipitates was significantly higher in patients with a silicone IOL than in those with a PMMA IOL, suggesting that use of silicone IOLs may increase the incidence of postoperative IOL precipitates.

Phacoemulsification versus extracapsular cataract extraction in patients with diabetes

OBJECTIVE

To compare phacoemulsification with extracapsular cataract surgery in patients with diabetes and to identify determinants of postoperative visual acuity.

DESIGN

Prospective, randomized, paired-eye trial.

PARTICIPANTS

Forty-six patients with diabetes and bilateral cataract.

INTERVENTION

Patients were allocated to phacoemulsification surgery with silicone intraocular lens to one randomly determined eye, and extracapsular cataract surgery with 7-mm polymethylmethacrylate intraocular lens to the other.

MAIN OUTCOME MEASURES

Logarithm of minimum angle of resolution visual acuity (logMAR VA), incidence of clinically significant macular edema (CSME), retinopathy progression, indices of anterior segment inflammation, and incidence of capsulotomy.

RESULTS

Compared with eyes undergoing phacoemulsification, eyes managed with extracapsular surgery had more anterior chamber cells (P = 0.0004) and flare (P = 0.007) 1 week after surgery and a higher incidence of posterior synechiae (P = 0.04) and intraocular lens deposits (P < 0.0005) in the first postoperative year. The need for posterior capsulotomy was greater in eyes undergoing extracapsular surgery (16 of 46 vs. 5 of 46, P = 0.01). No difference in incidence of postoperative CSME, progression of retinopathy, or development of high-risk proliferative retinopathy was identified between techniques (P = 1.0, 0.8, and 0.2). Median 1-year logMAR VA was worse in eyes undergoing extracapsular surgery (0.08 vs. 0.06, P = 0.02), especially in those with retinopathy (0.14 vs. 0.08, respectively; P = 0.01). The presence or absence of CSME at the time of surgery was the most significant determinant of 1-year logMAR VA in regression models for both extracapsular (P = 0.0004, R2 = 0.45) and phacoemulsification groups (P < 0.00005, R2 = 0.46).

CONCLUSIONS

Phacoemulsification is associated with better postoperative VA, less postoperative inflammation, and less need for capsulotomy than extracapsular cataract surgery in patients with diabetes. However, with both techniques, the principal determinant of postoperative VA appears to be the presence or absence of CSME at the time of surgery. Early intervention, reducing the risk that unrecognized CSME is present at the time of surgery, may be more critical to outcome than choice of surgical technique.

Late pigmented-membrane formation on silicone intraocular lenses after phacoemulsification with or without trabeculectomy

PURPOSE

To determine the incidence of late inflammatory membrane formation with pigment precipitates on foldable silicone or poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) after phacoemulsification with or without simultaneous trabeculectomy and to identify probable causative factors.

SETTING

Eye Department, Bnai-Zion Medical Center, and the Faculty of Medicine, the Technion, Haifa, Israel.

METHODS

In this retrospective study, 155 eyes (140 patients) were divided into 4 groups by the surgery performed: Group 1, phacoemulsification combined with trabeculectomy and foldable silicone IOL implantation (12 eyes); Group 2, phacoemulsification combined with trabeculectomy and PMMA IOL implantation (15 eyes); Group 3, phacoemulsification alone with foldable silicone IOL implantation (66 eyes); Group 4, phacoemulsification alone with PMMA IOL implantation (62 eyes). Preoperative, intraoperative, and postoperative data were compared.

RESULTS

Late inflammatory membranes were found on the anterior surface of 33% of the IOLs in Group 1, 3% in Group 3, and none in Groups 2 and 4. Membranes developed 3 to 4 months after surgery, were resistant to topical corticosteroid treatment and required repeated neodymium:YAG laser treatments. No correlation with preoperative, intraoperative, or postoperative factors was found.

CONCLUSION

Foldable silicone IOLs may induce late postoperative inflammatory membranes with pigment precipitates, especially after combined phacoemulsification and trabeculectomy.