Visual outcome following cataract extraction in patients aged 90 years and older.

PURPOSE: To analyse surgical outcomes following cataract surgery in patients aged 90 years and older. METHODS: A retrospective case series of 78 patients aged 90 years or more (82 eyes) undergoing cataract extraction between 2000 and 2006 was performed. Age, sex, ocular comorbidities, surgical reports, preoperative and postoperative visual acuity (VA), and postoperative complications were recorded. A comparison of visual outcome between different ocular comorbidity groups was performed. RESULTS: Average age was 91.8 years. The most common comorbidities were dry AMD (47.4%) and open-angle glaucoma (24.4%). No ocular comorbidity was found in only 22 patients (28.2%). Posterior capsular tear (8.5%) was the most prevalent operative complication.Overall VA improvement was 67.8%, whereas unchanged VA and VA worsening rates were 16.1% each. A total mean improvement of 0.63 logMAR was achieved (from preoperative 1.36 logMAR to postoperative 0.73 logMAR), whereas patients with no comorbidity achieved as high as 0.8 logMAR improvement (1.42-0.62 logMAR). Almost 17% of patients achieved uncorrected VA of 20/40 or better at day 7, compared to 7% preoperatively. Final VA of 20/40 or better was achieved in 25% of the patients. AMD patients showed lower final improvement rates and higher rates of unchanged VA, as compared to the no comorbidity and glaucoma group (statistically significant at day 7). CONCLUSIONS: Overall, approximately 70% of very elderly patients can achieve VA improvement, which rises to 82% in those without ocular comorbidity. Although patients with AMD show less improvement and more unchanged VA outcome rates, 62.5% can still enjoy improvement in VA.

Suturing a tear of the anterior capsulorhexis.

AIM: To describe a new technique of suturing a tear in the anterior capsulorhexis. METHODS: Continuous curvilinear capsulorhexis (CCC) with lens removal was done in five fresh cadaver eyes. The diameter of the CCC was measured with a calliper. Using the same calliper a tear of the CCC was created while opening the calliper's arms. The distance between the calliper's arms needed to tear the CCC was documented. Using 9-0 Ethilon 9011, CS 160-6 sutures in two eyes, 9-0 Prolene, D-8229, CTC-6L sutures in two eyes, and 10-0 Prolene, 9090, CTC-6 suture in one eye, the tears were sutured. A tear in the CCC was created again in the same way as the first tear. The distance between the calliper's arms needed to tear the CCC was documented again. RESULTS: Suturing of the tear restored some of the strength/elasticity of the CCC. Better results were found while using the 9-0 Prolene, D-8229, CTC-6L sutures than with the two others sutures. CONCLUSIONS: Suturing of a broken CCC can restore at least some of the strength/elasticity of the CCC. This can be important before intraocular lens (IOL) implantation for the safety of the implantation or after the implantation to ensure proper fixation of the IOL.

Downregulation of gene expression in the ageing lens: a possible contributory factor in senile cataract.

PURPOSE: To study the molecular characteristics of lens epithelial cells from patients with senile cataract by cDNA microarray technique. METHODS: Lens epithelial cells adhering to anterior capsules taken during cataract surgery collected from 108 patients, aged 56-92 years (senile cataract group), were pooled. Pooled epithelial cells of normal, noncataractous lenses from one patient with ocular trauma, one patient with lens subluxation, and 25 cadaveric eyes, all under the age of 55 years, served as a control. Total RNA was extracted by conventional methods from the two groups of cells, and a fluorescent probe was prepared for each group. The probes were hybridized on 9700 known human cDNA clones. Hybridized clones were analysed using a scanning laser and the results were processed by GEMTools (Incyte Genomics) software. RESULTS: A total of 1827 clones hybridized with the two probes. Of these, 400 showed differences of more than two-fold in gene expression between the two probes. Relative to controls, gene expression in the senile cataract lenses was upregulated in 318 clones and downregulated in 82. Three genes-filensin, inwardly rectifying potassium channel (IRPC), and pigment epithelium-derived factor (PEDF) were strongly downregulated (by 41.3-, 6.8-, and 5.9-fold, respectively) in senile cataract. CONCLUSIONS: Cataractogenesis is associated with numerous changes in the genetic profile of the lens epithelial cells. Since filensin, IRPC, and PEDF genes are known to have important roles in the physiology and morphology of the transparent lens, substantial downregulation of their expression might contribute to the formation of senile cataract.

A gene causing autosomal recessive cataract maps to the short arm of chromosome 3.

BACKGROUND: Fourteen loci have been associated with autosomal dominant cataract, but only one with the recessive form of the disease. OBJECTIVES: To find the chromosomal location of a gene causing autosomal recessive cataract in three inbred Arab families. METHODS: A single nucleotide polymorphism-based genome-wide search, with the Effvmetrix GeneChip HuSNP genotyping array, was performed on a pooled DNA sample from six affected family members in a search for regions showing homozygosity. Using conventional microsatellite markers, regions of homozygosity were further analyzed in all the families. RESULTS: A region on chromosome 3p spanning 43 megabases showed homozygosity with 13 consecutive SNPs. Three microsatellite markers from this region yielded lod scores > 3.00. A maximal two-point lod of 4.83 was obtained with the marker D3S1298 at theta = 0.004. Haplotype analysis placed the disease gene in a 20 Mb interval between D3S1768 and D3S2409. CONCLUSIONS: A gene causing autosomal recessive cataract maps to the short arm of chromosome 3.

Corneal endothelial cytotoxicity of diluted povidone--iodine.

PURPOSE: To assess corneal endothelial toxicity of diluted povidone-iodine (PI) in vivo and in vitro. SETTING: Cell Biology Laboratory and the Laboratory for Intraocular Microsurgery and Implants, Goldschleger Eye Research Institute, Sackler School of Medicine, Tel-Aviv University, Chaim Sheba Medical Center, Tel-Hashomer, Israel. METHODS: In an in vitro study, cultured bovine corneal endothelial cells were exposed to diluted PI. The degree of cell damage was determined by staining with trypan blue and by comparing the results to those in a control group. In an in vivo study, a single dose of diluted PI was injected into the anterior chamber of rabbit eyes, completely replacing the aqueous humor. The eyes were evaluated by clinical examination, specular microscopy, pachymetry, pneumotonometry, and histopathology and compared to a control group injected with a balanced salt solution. RESULTS: In vitro, PI concentrations of 0.05% or less did not induce endothelial cell damage. Significant damage was observed with a PI concentration of 0.1%. Calf serum concentrations of 1% and higher in the culture media protected the endothelial cell monolayer from cytotoxic damage by PI. Aqueous humor did not have a similar effect. In vivo, PI concentrations of 0.1% or less did not induce changes in corneal endothelium morphology or function as assessed by specular microscopy and pachymetry. A PI concentration of 1% served as a positive control, causing corneal edema and endothelial cell loss as demonstrated by pachymetry, histopathology, and elevated intraocular pressure. CONCLUSIONS: The concentrations of PI tolerated by animal endothelium in vitro and in vivo were higher than the reported bactericidal levels. These findings justify further investigation of the safety and efficacy of PI for intracameral prophylaxis during surgery.

Primary cataract extraction and intraocular lens implantation in penetrating ocular trauma.

PURPOSE: To analyze the postoperative outcome and complication rate after cataract extraction or lensectomy with primary intraocular lens (IOL) implantation for penetrating traumatic cataract. DESIGN: Retrospective, nonconsecutive, noncomparative case series. METHODS: We retrospectively reviewed the files of 21 patients who were admitted to our departments because of traumatic cataract with corneal or scleral laceration caused by penetrating trauma with or without intraocular foreign body (IOFB) from 1992 through 1997. Lens aspiration or manual extracapsular cataract extraction with primary IOL implantation was performed in all patients. Removal of an IOFB was performed in eight patients. MAIN OUTCOME MEASURES: Final visual acuity and deviation of actual refraction from emmetropia and from expected postoperative refraction. RESULTS: The mean follow-up was 20.4 months. Fourteen eyes (67%) achieved final visual acuity of 20/40 or better, 95% obtained 20/60 or better final visual acuity, and all eyes achieved 20/100 or better final visual acuity. Major causes of limited visual acuity were central corneal scar and central retinal injury. Eleven eyes (57%) experienced secondary cataract and underwent neodymium:yytrium-aluminum-garnet capsulotomy. CONCLUSIONS: Primary implantation of posterior chamber lenses after penetrating ocular trauma is associated with favorable visual outcome and a low rate of postoperative complications.

Experimental studies of capsular equator rings of soft latex.

PURPOSE: To determine the efficacy of wide equatorial rings of various materials in reducing posterior capsule opacification (PCO) and maintaining the circular contour of the capsular equator in a rabbit model. SETTING: Laboratory for Intraocular Microsurgery and Implants, Goldschleger Eye Research Institute, Tel-Aviv University, Sheba Medical Center, Tel-Hashomer, Israel. METHODS: Closed rings made of poly(methyl methacrylate), Teflon(R), polyurethane, and latex were introduced into the capsular bags of rabbit eyes after removal of the lens material. The soft latex rings were deemed the only practical rings for atraumatic implantation through a small incision. Latex rings of 2 dimensions with rectangular edges were implanted in 8 rabbits. One eye served as a control after lens removal and no ring implantation. The eyes were followed for up to 5 months and then evaluated by light microscopy. RESULTS: Posterior capsule opacification was minimal or absent in all animals implanted with the latex rings. Mild to moderate inflammatory reaction was noted in most eyes. It was caused by the ring material or secondary to long-standing pressure on the ciliary tissue. The rings also maintained well the circular contour of the capsular bags. CONCLUSIONS: Equatorial rings of soft latex with sharp rectangular edges were effective in minimizing PCO and maintaining the shape of the capsule after lens removal in rabbits. Soft rings made of a biocompatible material may be effective in humans.

A nonsense mutation (W9X) in CRYAA causes autosomal recessive cataract in an inbred Jewish Persian family.

PURPOSE: To identify the genetic defect causing autosomal recessive cataract in two inbred families. METHODS: Linkage analysis was performed with polymorphic markers close to 14 loci previously shown to be involved in autosomal dominant congenital cataract. In one of the families a gene segregating with the disease was analyzed by single-strand conformation polymorphism (SSCP) and eventually sequenced. RESULTS: Three polymorphic markers close to the CRYAA gene located on chromosome 21q segregated with the disease phenotype in one of the families, but not in the other. Sequencing of the CRYAA in this Jewish Persian family revealed a G-to-A substitution, resulting in the formation of a premature stop codon (W9X). CONCLUSIONS: A nonsense mutation in the CRYAA gene causes autosomal recessive cataract in one family. This constitutes the first description of the molecular defect underlying nonsyndromic autosomal recessive congenital cataract. That there was no linkage to this locus in another family provides evidence for genetic heterogeneity.

Vancomycin concentration in the vitreous after intravenous and intravitreal administration for postoperative endophthalmitis.

OBJECTIVES: To measure the concentrations of vancomycin in the vitreous of patients with postoperative endophthalmitis after administration of 1 g of vancomycin hydrochloride intravenously and injection of 1 mg of vancomycin hydrochloride into the vitreous, and to determine whether these concentrations are adequate for treatment of gram-positive infections. METHODS: Patients with acute postoperative endophthalmitis were treated with intravenous administration of 1 g of vancomycin hydrochloride followed by vitrectomy and collection of vitreous samples 1 to 5 hours later. Intravitreal vancomycin and ceftazidime were given. Vitreous samples were cultured and their vancomycin concentrations assayed. Minimal inhibitory concentrations of vancomycin for the isolated vitreal pathogens, and serum and vitreous cidal activity were determined. RESULTS: Eighteen patients with acute postoperative endophthalmitis were studied. Fourteen vitreous samples were available after intravenous vancomycin administration, and 4 vitreous samples were available after intravitreal vancomycin administration. After intravenous injection, vitreous vancomycin concentrations ranged from 0.4 to 4.5 microg/mL. Minimal inhibitory concentrations in these samples, obtained from 10 bacterial isolates, were below the therapeutic levels for most causative organisms, including staphylococci. Vitreous cidal activity values were negative at a dilution of 1:2 in 9 of 10 patients examined. After a 1-mg intravitreal injection, vancomycin concentrations in vitreous samples obtained by a second tap from 4 patients 44 to 72 hours later were 182, 138, 58, and 25 microg/mL. In 2 patients in whom measurements were obtained, vitreous cidal activity values were 1:512 and 1:32. CONCLUSION: Vitreous vancomycin concentrations for the treatment of gram-positive endophthalmitis were nontherapeutic after intravenous administration but therapeutic after intravitreal administration.

Topical anesthesia using lidocaine gel for cataract surgery.

PURPOSE: To assess the safety and efficacy of topical anesthesia using lidocaine gel in cataract surgery. SETTING: Department of Ophthalmology, Meir Hospital, Sapir Medical Center, Kfar-Saba, Israel. METHODS: One hundred cataract procedures (48 manual extracapsular cataract extraction [ECCE] and 52 phacoemulsification) were performed using lidocaine 2% gel as the sole anesthetic agent. The gel was applied 3 to 5 times prior to surgery. Intraoperative and postoperative data were recorded, and patients were asked to grade the pain on a scale of 0 (no pain) to 10 (unbearable pain). RESULTS: Sixty-two percent of patients having manual ECCE and 74% having phacoemulsification reported no pain during surgery (score 0). The mean pain score in the manual ECCE group was 0.99 +/- 1.64 (SD); 3 patients required an additional intracameral lidocaine injection. The mean score in the phacoemulsification group was 0.72 +/- 1.47; no patient required additional anesthesia. CONCLUSIONS: Topical application using lidocaine 2% gel is safe and highly effective, especially in clear corneal phacoemulsification. The gel also provides prolonged lubrication, further facilitating surgery.

Effect of expandable full-size intraocular lenses on lens centration and capsule opacification in rabbits.

PURPOSE: To study the effects of expandable, hydrogel, full-size lenses (FSLs) on lens centration and posterior capsule opacification (PCO) in the rabbit model. SETTING: Center for intraocular Lens Research, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: Small FSLs designed for human eyes were implanted unilaterally in 20 rabbit eyes. Lens centration and PCO in these eyes were compared with those in eyes with conventional poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) or aphakia in the fellow eyes. In a second experiment, medium-size or large FSLs designed for rabbit eyes were implanted in 20 rabbit eyes and the results compared with those in eyes with conventional PMMA IOLs. Slitlamp examination of all eyes was performed regularly, after enucleation, gross inspection and microscopic studies were performed. RESULTS: Decentration of FSLs occurred in the presence of an anterior capsule tear or very large capsulorhexis. Posterior capsule opacification developed only at sites where the implanted lens was not in contact with the capsule. Aphakic eyes and looped IOLs developed Soemmering's rings peripherally. In eyes with small FSLs, PCO developed between the lens and the center of the posterior capsule, whereas in eyes with large FSLs, only small amounts of central PCO developed. Retained high-viscosity viscoelastic material had no effect on PCO development. CONCLUSIONS: Complete refilling of the capsular bag by a full-size IOL was associated with excellent centration and only a small degree of PCO. Elastic lenses may thus serve as a starting point for the development of an artificial lens with accommodative function.

Prevention of posterior capsule opacification with the CO2 laser.

BACKGROUND AND OBJECTIVE: Posterior capsule opacification (PCO) is a common complication after cataract extraction, despite the modern surgical techniques and lenses being used for this procedure. Its prevention challenged many investigators, because the current treatment of choice, capsulotomy with Nd:YAG laser, is associated with sight-threatening complications. In the present study, the authors investigated two approaches of preventing PCO using the CO2 laser. MATERIALS AND METHODS: A 15-W CO2 laser with a 17- or 18-gauge hollow probe was used on 20 sheep eyes and 14 rabbit eyes. Lens extraction was done by phacoemulsification. In the equatorial treatment study, the anterior chamber was filled with either air or a viscoelastic substance, and laser burns were applied to the equator of the lens capsule and to the peripheral anterior capsule to destroy the epithelial cells. In the capsulotomy study, a primary posterior capsulotomy was created by delivering 1 to 3 laser shots to the capsule behind an implanted intraocular lens (IOL). RESULTS: The CO2 laser was satisfactory in sheep eyes after filling the anterior chamber with air. In rabbit eyes, however, it was technically impractical to work with air. Using a viscoelastic material to maintain the anterior chamber, the hollow probe of the CO2 laser becomes plugged up and therefore is unable to affect the ocular tissue. However, by combining viscoelastic and air pumping, both the destruction of the lens epithelial cells and the creation of a central posterior opening behind a capsular-fixated IOL was repeatedly achieved. CONCLUSION: Using the CO2 laser for destruction of lens epithelial cells and the creation of controlled posterior capsulotomy is feasible and practical. A different design of the probe (closed gauge) is required to enable it to operate clinically in a fluid or viscoelastic environment.

The role of intraocular lenses in anterior chamber contamination during cataract surgery.

BACKGROUND: Bacterial endophthalmitis is a rare vision-threatening disease, usually caused by microorganisms that are natural inhabitants of the eye lids and conjunctiva. This study was conducted to investigate the role of intraocular lenses (IOLs) in introducing bacterial contamination into the eye during cataract surgery and the efficacy of povidone-iodine solution in prevention this ocular inoculum. METHODS: Fifty patients underwent routine cataract surgery and intraocular lens implantation. One group of the patients was pretreated with external disinfection using povidone-iodine 4% before surgery, while the other group was only pretreated with saline irrigation. Before IOL implantation, a test IOL was placed on the conjunctiva and taken for microbiological studies. Anterior chamber tap was done at the beginning and at the end of each operation. Positive bacterial growth was followed by bacterial identification and sensitivity tests to various antibiotics. RESULTS: Bacterial growth was obtained in 14 of the 50 eyes (28%); in 5 eyes the organism was cultured from tapped aqueous and in 9 eyes from the test IOLs. Prophylactic use of povidone-iodine 4% solution effectively reduced the contamination rate from 34.7% to 16.7%. Coagulase-negative staphylococci were the most common organisms isolated (72%). Most organisms were sensitive to vancomycin (86%) and to fucidic acid (71%). There were no cases of clinical endophthalmitis. CONCLUSIONS: IOLs are apparently potential vehicles for introduction of intraocular bacterial contamination. Instillation of povidone-iodine 4% into the cul-de-sac reduces the risk of bacterial inoculum. Vancomycin is the most effective single agent against intraocular contamination. In order to reduce potential intraocular contamination it is advisable to avoid contact between the IOL and ocular tissues.

Effect of aspirin intake on bleeding during cataract surgery.

PURPOSE: To study the association between chronic intake of aspirin and intraoperative bleeding during cataract surgery and the effect of discontinuing the medication before surgery. SETTING: Department of Ophthalmology, Meir Hospital, Sapir Medical Center, Kfar-Saba, Israel. METHODS: Sixty-one patients having cataract surgery and receiving aspirin to prevent thromboembolic events were divided into 3 groups: Group A, continuation of the medication; Group B, cessation of aspirin intake for 2 to 5 days before surgery; Group C, cessation of medication for 7 to 10 days before surgery. Blood tests of coagulation parameters, a detailed questionnaire, and 1 day and 1 week follow-up were evaluated. RESULTS: There were no significant differences in blood tests and the amount and incidence of intraoperative bleeding among the 3 groups. Diathermy was used somewhat more in Group A; however, there was no difficulty stopping the bleeding in any case and discontinuation of the medication had no effect on the intraoperative course or postoperative outcome. CONCLUSIONS: Aspirin intake was not associated with significant intraoperative bleeding; thus, discontinuation of aspirin is usually not indicated. Clear corneal phacoemulsification is advantageous in patients receiving antiplatelet therapy.

Experimental studies on viscofluids for intraocular surgery.

PURPOSE: To investigate the feasibility and efficacy of using diluted viscofluids during intraocular surgery. SETTING: Laboratory for Intraocular Microsurgery and Implants, Goldschleger Eye Research Institute, and the Sackler School of Medicine, Tel-Hashomer, Israel. METHODS: Diluted hyaluronic acid (0.06 to 0.12%) in balanced salt solutions were irrigated through the phacoemulsification machine or a separate irrigation line (i.e., anterior chamber maintainer). Irrigation was facilitated by increasing the atmospheric pressure in the bottle using compressed air. Experimental surgery was done in rabbit eyes. RESULTS: A viscous fluid could be irrigated at any practical rate by increasing the height of the bottle, increasing the atmospheric pressure within the bottle, or both. Experimental surgeries showed that viscofluids maintained intraocular pressure and anterior chamber volume, allowed safe intraocular manipulations, reduced turbulence in the anterior chamber, and probably provided tissue protection. CONCLUSION: Viscofluids irrigated using a high-pressure system combined the advantages of continuous irrigation of fluids and the protective qualities of viscoelastics in this rabbit eye study.

A safety suture for implantation of posterior chamber intraocular lenses in complicated cases.

Implantation of a posterior chamber intraocular lens can be difficult and risky in complicated cases such as a large tear in the posterior capsule, a cloudy cornea, or a small pupil. The author describes a technique for performing a safe implantation. The intraocular lens is supported by a suspension suture, which is threaded through a positioning hole or tied to the lens haptic. The suture is removed once a stable fixation is achieved.