Endophthalmitis following cataract surgery in Sweden: national prospective survey 1999-2001

Comparison of the influence of intracameral gentamicin, gatifloxacin, and moxifloxacin on the corneal endothelium in a rabbit model

PURPOSE

To compare the effect of three intracameral antibiotics, gentamicin (GM), gatifloxacin (GFLX), and moxifloxacin (MFLX), on the rabbit corneal endothelium.

METHODS

Twenty-four eyes from 18 rabbits were used. In the GM treatment group of 12 eyes, a dose of 20 mg/ml, 2 mg/ml, 200 μg/ml, or 20 μg/ml of GM was injected into the anterior chamber. In the GFLX and MFLX treatment groups were injected into the anterior chamber of three eyes. The central corneal thickness was measured. The eyes were then enucleated for observation under scanning electron microscopy.

RESULTS

Three days after the intracameral injection, a significant difference in central corneal thickness was found between the GM 20 mg/ml group and the control group (P < 0.05), but not between any other groups. The damage rate at the endothelial cell level was 67% in the GM 20 mg/ml group, 56% in the GM 2 mg/ml group, 33% in the GM 200 μg/ml group, 22% in the GM 20 μg/ml group, 22% in the GFLX group, and 0% in the MFLX group.

CONCLUSIONS

Intracameral GFLX or MFLX was almost nontoxic to the rabbit corneal endothelium, in contrast to the toxic results of intracameral GM 20 and 2 mg/ml.

Prophylaxis of postoperative endophthalmitis following cataract surgery: current status and future directions

Endophthalmitis is an uncommon but potentially devastating intraocular infection that can occur after routine cataract surgery. Although a broad spectrum of organisms have been shown to cause acute postoperative endophthalmitis, most cases are caused by Gram-positive bacteria, which may be introduced at the time of surgery from colonization of adjacent conjunctiva or eyelid skin. Risk factors for the development of endophthalmitis following cataract surgery include patient age, intraoperative surgical complications and poor wound construction. There are several antibacterial strategies employed to prevent postoperative endophthalmitis, with topical, intracameral and subconjunctival delivery being the most common. Worldwide, there seems to be significant regional variance in the type and method of prophylactic antibacterial regimens; for example, topical fluoroquinolones are commonly used in the US, while intracameral cephalosporins are employed widely in Europe. The optimal antibacterial strategy for the prevention of endophthalmitis should be safe, inexpensive and broad in microbiological activity spectrum, while not requiring patient compliance for its effectiveness.

Acute endophthalmitis after cataract surgery at a referral centre in Northern Taiwan: review of the causative organisms, antibiotic susceptibility, and clinical features

PURPOSES

The aims of this study were to describe the bacterial isolates and treatment outcomes of endophthalmitis after cataract surgery at a referral centre in Northern Taiwan.

METHODS

This was a retrospective, interventional, and observational series. Medical records were review of patients with clinical diagnosed, and/or culture-proven bacterial endophthalmitis at a tertiary referral centre in Northern Taiwan from January 2002 to December 2008. Treatment generally conformed to standard guidelines. Main outcome measurements were results of organism culture, antibiotic susceptibility of isolated bacteria, and visual acuity (VA) outcome.

RESULTS

Thirty-four patients had positive cultures. A total of 55.9% of the culture-positive isolates were Gram negative and 44.1% were Gram positive. Pseudomonas aeruginosa was the most commonly isolated organism. Eighteen patients had final VA better than 5/200, and 41 had final VA worse than 5/200. In multiple linear regression analysis, female gender, presence of hypopyon, and worse baseline VA were significant independent predictors of worse visual outcome.

CONCLUSIONS

It was found that at a referral centre in Northern Taiwan, the majority of bacterial isolates were Gram negative in acute postoperative bacterial endophthalmitis after cataract surgery and P. aeruginosa was the most common bacterial isolate.

Acute endophthalmitis after cataract surgery: 250 consecutive cases treated at a tertiary referral center in the Netherlands

PURPOSE

To evaluate the clinical characteristics, bacterial culture, and visual outcome of patients with acute endophthalmitis after cataract surgery.

DESIGN

Retrospective consecutive interventional case series.

METHODS

Clinical notes from patients treated for acute endophthalmitis after cataract surgery in a single center from 1996 to 2006 were reviewed. Patients with less than 1 month of follow-up and missing bacterial cultures were excluded. Vitreous biopsy or primary vitrectomy followed by intravitreal injection of vancomycin and ceftazidime (+/- prednisolone) was performed. Main outcome measures were bacterial culture and final visual acuity.

RESULTS

Bacterial cultures (total 250 cases) showed bacterial growth in 166 cases (66.4%). From these 166 cultures, 89 (53.6%) revealed gram-positive coagulase-negative, 63 (38.0%) other gram-positive, 10 (6.0%) gram-negative, and 4 (2.4%) polymicrobial cultures. Vitreous biopsy with intravitreal antibiotics injection was performed in 225 (90.0%) of cases. Primary vitrectomy with intravitreal antibiotics was performed in 25 eyes (10.0%). Final visual acuity >/=0.5 was achieved in 129 (51.6%) of all cases, 54 (60.7%) of the 89 gram-positive coagulase-negative cultures, 20 (31.7%) of the 63 other gram-positive cultures, 5 (50.0%) of the 10 gram-negative cultures, and 9 (45.0%) of the 20 Staphylococcus aureus cultures. There was no additional effect for treatment by primary vitrectomy or intravitreal prednisolone.

CONCLUSIONS

Treatment outcome after endophthalmitis is highly dependent on the causative organism. Treatment outcomes for gram-negative bacteria and S. aureus may be better than previously reported. Prompt treatment of endophthalmitis remains essential and the role of complete primary vitrectomy remains subject to debate.

[Intraocular lens and cataract surgery: comparison between bacterial adhesion and risk of postoperative endophthalmitis according to intraocular lens biomaterial]

Cataract surgery is a usually successful procedure that restores vision by replacing the natural lens with an intraocular lens (IOL). Acute postoperative endophthalmitis is still one of the most serious complications of cataract surgery. Its incidence has been reported to be between 0.04% and 0.32%. Precisely why bacteria induce endophthalmitis is not entirely understood. Indeed the risk of its development may be influenced by several factors. Among them, bacterial adhesion to the IOL has been recently emphasized in the ophthalmology literature. Indeed, the ability of an organism to adhere to the IOL surface is believed to be associated with a risk of infection at the implantation site. Several studies have demonstrated that bacterial adhesion is influenced by IOL materials. Ever since, numerous studies have investigated the interactions between bacteria and different types of IOLs to determine which biomaterial would be most permissive to bacterial adherence. This article reviews all the epidemiological and experimental data relating to the study of the relationship between bacterial adhesion, IOL material, and risk of developing postoperative endophthalmitis. Even if discrepancies between these studies exist, mainly stemming from the use of different experimental conditions and protocols, it seems that bacterial adhesion is strongly influenced by IOL material. Epidemiological studies suggest that the implantation of silicone IOLs might be associated with increased rates of endophthalmitis. Experimental studies reach similar conclusions showing that hydrophobic IOLs such as silicone or acrylic hydrophobic IOLs are more permissive to bacterial adhesion and growth than hydrophilic IOLs such as acrylic hydrophilic IOLs. Among the interactions that govern bacterial attachment to the IOLs, it seems that hydrophilic-hydrophobic interactions have the greatest influence. Nevertheless, since bacterial adhesion is a complicated process affected by many factors, the conclusions drawn by these results have to be interpreted with care. Further investigations are still needed to understand the connections between IOL material and endophthalmitis.

Multistate outbreak of toxic anterior segment syndrome, 2005

PURPOSE

To present the findings of an outbreak of toxic anterior segment syndrome (TASS).

SETTING

Six states, 7 ophthalmology surgical centers, United States.

METHODS

Cases were identified through electronic communication networks and via reports to a national TASS referral center. Information on the procedure, details of instrument reprocessing, and products used during cataract surgery were also collected. Medications used during the procedures were tested for endotoxin using a kinetic assay.

RESULTS

The search identified 112 case patients (median age 74 years) from 7 centers from July 19, 2005, through November 28, 2005. Common presenting clinical features included blurred vision (60%), anterior segment inflammation (49%), and cell deposition (56%). Of the patients, 100 (89%) had been exposed to a single brand of balanced salt solution manufactured by Cytosol Laboratories and distributed by Advanced Medical Optics as AMO Endosol. Two patients continued to have residual symptoms. There were no reports of significant breaches in sterile technique or instrument reprocessing. Of 14 balanced salt solution lots, 5 (35%) had levels exceeding the endotoxin limit (0.5 EU/mL). Based on these findings, the balanced salt solution product was withdrawn, resulting in a termination of the outbreak.

CONCLUSIONS

This is the first known report of an outbreak of TASS caused by intrinsic contamination of a product with endotoxin. Ophthalmologists and epidemiologists should be aware of TASS and its common causes. To facilitate investigations of adverse outcomes such as TASS, those performing cataract surgeries should document the type and lot numbers of products used intraoperatively.

Adherence and kinetics of biofilm formation of Staphylococcus epidermidis to different types of intraocular lenses under dynamic flow conditions

PURPOSE

To compare the adherence and biofilm formation of Staphylococcus epidermidis under in vitro flow conditions on intraocular lenses (IOLs) made of 4 biomaterials: poly(methyl methacrylate) (PMMA), silicone, hydrophilic acrylic, and hydrophobic acrylic.

SETTING

Department of Ophthalmology, Croix-Rousse University Hospital and University Research Laboratory, Lyon, France.

METHODS

Intraocular lenses were placed in a bioreactor designed to replicate intraocular conditions. The model consisted of Tygon tubing connected to a vial. Three septa allowed the entry and elimination of the artificial aqueous humor and inoculation of the bacterial suspension. The first of 2 pumps moved the aqueous humor along the circuit; the second pump regulated the flow at which the nutritive environment was regenerated. At various times (12, 16, 24, 40, 48, 60, and 72 hours), IOLs were taken from this environment and the bound bacteria were removed and counted. The distribution of bacterial adhesion on the IOLs was modeled using polynomial Poisson regression. To test the effect of the IOL biomaterial on bacterial adhesion, likelihood ratio tests were performed.

RESULTS

The model provided the kinetics of S epidermidis biofilm growth on IOLs. The biofilm growth on each of the 4 biomaterials occurred in 3 phases: latent, dynamic or accelerated growth, and linear growth. The extent of bacterial binding to IOLs increased from hydrophilic acrylic polymer to PMMA, hydrophobic acrylic, and silicone. The differences were statistically significant.

CONCLUSION

Bacterial adhesion to and biofilm development on the IOL surface depended on the characteristics of the biomaterial.

Endogenous endophthalmitis: microorganisms, disposition and prognosis

PURPOSE

Endogenous endophthalmitis is a severe and potentially blinding complication caused by haematogenous spreading of microorganisms. We evaluated the causative microorganisms, disposition to and prognosis of the disease.

METHODS

Thirty-one eyes of 28 patients were treated between 1996 and 2006 as the result of an endogenous endophthalmitis.

RESULTS

The microorganisms responsible for infection could be identified in 94% of all eyes investigated. Candida isolates were obtained in 15, gram-positive isolates in 11, gram-negative in one and Aspergillus in two of the 29 eyes studied. The majority of patients suffered from severe general disease (immuno-deficiency, severe surgical procedures, diabetes mellitus) and one third were intravenous drug abusers. Only one patient was otherwise healthy. The prognosis depended on the causative microorganisms. Whereas none of the eyes with Candida infection became blind, all except two of the eyes with gram-positive bacteria, Nocardia or Aspergillus infection lost visual function or had to be enucleated.

CONCLUSION

Compared to postoperative endophthalmitis, patients with endogenous endophthalmitis are more likely to have Candida isolates. Visual prognosis depends mainly on the underlying microorganisms, and is particularly poor in the case of infection with gram-positive bacteria or Aspergillus.

Endophthalmitis: a reappraisal of incidence and treatment

PURPOSE OF REVIEW

The current publications that address either the incidence or treatment of endophthalmitis are reviewed.

RECENT FINDINGS

A large body of published research has recently addressed the issue of potential increases in the incidence of endophthalmitis, especially postcataract endophthalmitis. Additional studies have evaluated relatively new antibiotics and their potential effect on the prevention and treatment of endophthalmitis.

SUMMARY

Although there appears to be a renewed effort to report the incidence and theorized risk factors for postcataract endophthalmitis, there are wide discrepancies in the rate and potential causes of postoperative endophthalmitis. In regards to endophthalmitis treatment, helpful findings regarding the potency of newer antibiotics and the appropriateness of subconjunctival antibiotics are reviewed.

Prophylaxis of postoperative endophthalmitis following cataract surgery: results of the ESCRS multicenter study and identification of risk factors

PURPOSE

To identify risk factors and describe the effects of antibiotic prophylaxis on the incidence of postoperative endophthalmitis after cataract surgery based on analysis of the findings of the European Society of Cataract & Refractive Surgeons (ESCRS) multicenter study.

SETTING

Twenty-four ophthalmology units in Austria, Belgium, Germany, Italy, Poland, Portugal, Spain, Turkey, and the United Kingdom.

METHODS

A prospective randomized partially masked multicenter cataract surgery study recruited 16 603 patients. The study was based on a 2 x 2 factorial design, with intracameral cefuroxime and topical perioperative levofloxacin factors resulting in 4 treatment groups. The comparison of case and non-case data was performed using multivariable logistic regression analyses. Odds ratios (ORs) associated with treatment effects and other risk factors were estimated.

RESULTS

Twenty-nine patients presented with endophthalmitis, of whom 20 were classified as having proven infective endophthalmitis. The absence of an intracameral cefuroxime prophylactic regimen at 1 mg in 0.1 mL normal saline was associated with a 4.92-fold increase (95% confidence interval [CI], 1.87-12.9) in the risk for total postoperative endophthalmitis. In addition, the use of clear corneal incisions (CCIs) compared to scleral tunnels was associated with a 5.88-fold increase (95% CI, 1.34-25.9) in risk and the use of silicone intraocular lens (IOL) optic material compared to acrylic with a 3.13-fold increase (95% CI, 1.47-6.67). The presence of surgical complications increased the risk for total endophthalmitis 4.95-fold (95% CI, 1.68-14.6), and more experienced surgeons were more likely to be associated with endophthalmitis cases. When considering only proven infective endophthalmitis cases, the absence of cefuroxime and the use of silicone IOL optic material were significantly associated with an increased risk, and there was evidence that men were more predisposed to infection (OR, 2.70; 95% CI, 1.07-6.8).

CONCLUSIONS

Use of intracameral cefuroxime at the end of surgery reduced the occurrence of postoperative endophthalmitis. Additional risk factors associated with endophthalmitis after cataract surgery included CCIs and the use of silicone IOLs.

Incidence of endophthalmitis after cataract surgery in Japan

PURPOSE

To estimate the incidence rate of endophthalmitis after cataract surgery performed by Japanese surgeons.

METHODS

A sample of 20% of members of the Japanese Society of Ophthalmic Surgeons was randomly selected. Each member was sent a postal survey asking for information on the number of cataract surgeries performed in 2003 and the number of postsurgery cases of endophthalmitis.

RESULTS

Replies were received from 78.7% (513/652) of survey recipients. The total number of cataract surgeries was 100 539, among which 52 cases of endophthalmitis occurred, resulting in an overall incidence rate of 0.052%. Incidence rates were 0.049% (38/78 170) for scleral incision phacoemulsification and 0.043% (9/20 894) for clear corneal incision phacoemulsification, with no significant difference between groups. The average annual volumes of surgery were 210 and 280 cases for surgeons who preferred scleral incision and clear corneal incision, respectively. There was a significant difference between volumes (Student's t-test, p < 0.01). The incidence of endophthalmitis was significantly lower with high-volume (> 300 cases/year) surgeons than with low-volume (< or = 300 cases/year) surgeons (0.040% versus 0.066%, chi-square test, p < 0.05).

CONCLUSIONS

The incidence of endophthalmitis after cataract surgery in Japan as estimated by a postal survey was low (0.052%) and consistent with rates reported previously. Surgeons who preferred clear corneal incision performed significantly more surgeries annually, but the incidence of endophthalmitis was similar between scleral and clear corneal incision phacoemulsification surgery.

Pharmacokinetics of vancomycin following intracameral bolus injection in patients undergoing phacoemulsification cataract surgery

AIM

To determine the elimination kinetics of intracameral vancomycin administered as a bolus injection at the end of phacoemulsification cataract surgery.

METHODS

Vancomycin 1 mg/0.1 ml saline solution was administered to 19 patients by intracameral bolus injection at the end of routine cataract surgery. The aqueous concentration of vancomycin was determined in nine patients 1 minute after administration and in 10 patients 18-24 hours postoperatively. Aqueous samples were obtained by inserting a Rycroft cannula into the anterior chamber via the side port incision. Fluorescence polarisation immunoassay was used to calculate the aqueous vancomycin concentration.

RESULTS

The median (interquartile range) vancomycin concentration was 5458 (4756-6389) mg/l at 1 minute and 40.6 (25.9-47.1) mg/l 18 to 24 hours (median 19 hours) postoperatively. The vancomycin concentration exceeded the minimum inhibitory concentration (MIC) of endophthalmitis-causing gram-positive bacteria by a factor of 4 for up to 26 hours postoperatively. No adverse event or reaction was noted.

CONCLUSION

Following bolus intracameral injection at the end of cataract surgery the concentration of vancomycin in the anterior chamber vastly exceeds its MIC for at least 24 hours but is predicted to fall below the MIC after 33 hours.

Endophthalmitis after cataract surgery: a nationwide prospective study evaluating incidence in relation to incision type and location

PURPOSE

To establish the nationwide rate of postoperative endophthalmitis (PE) after cataract extraction (CE) and to study the relationship between PE and type of incision and other possible risk factors.

DESIGN

Prospective, multicenter, comparative, nonrandomized, observational study.

PARTICIPANTS

All cataract surgeries in Sweden performed from January 2002 through December 2004 and all endophthalmitis cases in the same period that were reported to the Swedish National Cataract Register (NCR).

METHODS

Through a standard reporting form sent to the NCR, patient and operation technique data were recorded. In addition, PE cases with a traceable number to the main register were collected. Various parameters with a possible impact on endophthalmitis development were evaluated. Univariate analyses and logistic regression were statistical methods.

MAIN OUTCOME MEASURES

The rate and etiology of PE; possible risk factors pertaining to patient history and operation technique, with a special emphasis on incision type and location; use of injector for the intraocular lens implantation; kind of prophylaxis; and presence of peroperative communication between the anterior chamber and vitreous.

RESULTS

The overall rate of PE was 0.048% (109 cases in 225 471 CEs). Incidences of PE were 0.053% with clear corneal incisions and 0.036% with sclerocorneal incisions (P = 0.14, logistic regression analysis). The corresponding results were 0.040% for superior incisions and 0.055% for temporal incisions (P = 0.14). Communication between the anterior segment and vitreous was found to be a highly significant independent risk factor for PE (P<0.001), as were patient age > or = 85 years (P<0.001) and the nonuse of intracameral cefuroxime (P<0.001).

CONCLUSIONS

The overall rate of PE after cataract surgery is low in Sweden, which may be a consequence of the widespread use of prophylactic intracameral cefuroxime. Only a trend for an increased risk of PE was detected for clear corneal and temporal wounds. The present data indicate that the use of clear corneal and/or temporal approaches will result in 1 additional PE case in approximately 5500 procedures on top of the PE rate after sclerocorneal or superior incisions, which was approximately 1 case in 2400 operations.

Reducing the risk for endophthalmitis after cataract surgery: Population-based nested case-control study

PURPOSE

To characterize operative and nonoperative risks for the potentially blinding complication of endophthalmitis after cataract surgery.

SETTING

Ophthalmology services for the whole state of Western Australia.

METHODS

This retrospective population-based nested case-control study in Western Australia covered the period between 1980 and 2000. For each of the 205 cases of endophthalmitis, 4 time-matched controls were randomly selected from all cataract operations performed in the state. Conditional logistic regression was used to estimate multivariate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the risk factors of interest.

RESULTS

Wound location, suturing the wound, and type of cataract operation did not affect the risk for postoperative endophthalmitis. Antibiotic prophylaxis reduced the risk, but only if given as a subconjunctival injection (OR, 0.46; 95% CI, 0.29-0.70). The risk for endophthalmitis was greater with same-day surgery (OR, 2.27; 95% CI, 1.52-3.41) than with admission the day before surgery. A concurrent eyelid procedure was a substantial risk. Surgeons within 2 years of obtaining specialist qualifications were more likely to have a case of endophthalmitis, although this was partly the result of more posterior capsule breaches. Posterior capsule breach increased the risk when it occurred in private hospitals (OR, 13.57; 95% CI, 4.00-45.99), but not in public hospitals.

CONCLUSIONS

Nonoperative as well as operative factors are important in the prevention of endophthalmitis. Subconjunctival injection of antibiotics appears to be beneficial for endophthalmitis prophylaxis. The model showed that active risk management strategies designed to optimize hospitalization and chemoprophylaxis may reduce the incidence of endophthalmitis by up to 81%.

A survey of measures used for the prevention of postoperative endophthalmitis after cataract surgery in the United Kingdom

PURPOSE

This study investigates the current practice of United Kingdom (UK) ophthalmologists in perioperative antibiotic and antiseptic use in cataract surgery.

MATERIALS AND METHODS

A telephone interview survey was conducted with ophthalmic staff at all ophthalmic training units in the UK in October and November 2005.

RESULTS

The practices of a total of 800 consultants were ascertained. Preoperatively, 795 (99.4%) surgeons used povidone-iodine to prepare the skin. In all, 558 (69.8%) instilled 5 or 10% povidone-iodine in the conjunctival sac; 47 (5.9%) gave preoperative antibiotic eyedrops. Intraoperatively, intracameral antibiotics were given either as a bolus [80 (10.0%) intracameral cefuroxime, 29 (3.6%) intracameral vancomycin] or in the irrigating fluid [33 (4.1%) vancomycin]. 48 (6.0%) gave subconjunctival gentamycin only routinely, 531 (66.4%) gave subconjunctival cefuroxime, and 39 (4.9%) gave other subconjunctival antibiotics. A single dose of topical antibiotics was given by 134 (16.8%) surgeons. Postoperatively, 515 (64.4%) used a combination steroid and neomycin eyedrop, and 213 (26.6%) gave a separate steroid and chloramphenicol eyedrop.

CONCLUSIONS

This study reveals wide variations in the choice and duration of antibiotics used by UK ophthalmologists. The predominant methods of intraoperative prophylaxis are subconjunctival cefuroxime and intracameral cefuroxime. Most surgeons used a neomycin eyedrop for postoperative prophylaxis.

Cataract surgery practice and endophthalmitis prevention by Australian and New Zealand ophthalmologists

PURPOSE

Our aim was to examine current cataract surgery practice and the methods of chemoprophylaxis used in Australia and New Zealand, and to determine if these factors were related to self-reported incidence rates of postoperative endophthalmitis.

METHODS

All Fellows and trainees of the Royal Australian and New Zealand College of Ophthalmologists were surveyed about their cataract surgery practices and methods of chemoprophylaxis for the prevention of postoperative endophthalmitis. Associations between self-reported incidence rates of endophthalmitis and clinical practice were examined using multivariate Poisson regression modelling.

RESULTS

There were 731 respondents (81.6% of 896 surveyed) to the survey. Respondents reported a total of 162,120 cataract operations and 92 cases of endophthalmitis in 2003, a cumulative incidence of 0.057%. The self-reported incidence of endophthalmitis varied from 0.034% in Victoria to 0.56% in the Northern Territory. Topical antibiotics were used preoperatively by 46.7% compared with 97.4% postoperatively; while only 44.1% used subconjunctival antibiotics. The routine use of subconjunctival antibiotic halved the self-reported incidence of postoperative endophthalmitis (incidence rate ratio 0.53, 95% confidence interval 0.30-0.92).

CONCLUSIONS

Subconjunctival antibiotics may be beneficial in the prevention of endophthalmitis after cataract surgery.

Bacterial contamination in the anterior chamber after povidone–iodine application and the effect of the lens implantation device

PURPOSE

To assess the incidence of anterior chamber bacterial contamination during cataract surgery, and compare results of injector implantation and forceps implantation of foldable intraocular lenses (IOLs).

SETTING

Department of Ophthalmology and Institute of Medical Microbiology, Semmelweis University, Budapest, Hungary.

METHODS

This prospective randomized controlled clinical study comprised 97 eyes of 96 patients. Antibiotic eyedrops were not used; however, povidone-iodine 10% solution was used to prepare the eyebrow and eyelids and povidone-iodine 5% to disinfect the ocular surface. A Steri-Drape (3M) was used to surround the eye. Aqueous fluid samples were aspirated from the anterior chamber at the beginning and the end of surgery. The samples were cultured for 14 days under aerobic and anaerobic conditions simultaneously. Cataract surgery was performed using a sutureless, superotemporal, clear corneal phacoemulsification technique. The IOL was implanted with an injector (n = 47) or a forceps (n = 50), with the instrument randomly selected. The frequency of positive bacterial cultures with each implantation method was compared using the Fisher exact test.

RESULTS

Bacteria were found in the conjunctival samples in 21 eyes (21.65%) before povidone-iodine application and in 4 eyes (4.12%) after disinfection. The anterior chamber sample before surgery was culture positive for Staphylococcus epidermidis in 2 eyes and for Micrococcus luteus in 1 eye. After surgery, the culture was positive for S epidermidis in 1 eye (2.15%) in the injector group and 1 eye (2.00%) in the forceps group (P = .74). Neither sample came from an eye that had a positive culture preoperatively. There were no intraoperative complications.

CONCLUSIONS

In uneventful clear corneal phacoemulsification, meticulous technique can prevent antibiotic use during surgery. No difference in anterior chamber bacterial contamination was found between IOL implantation using an injector or a forceps.

Influence of intraocular lens material on the development of acute endophthalmitis after cataract surgery?

PURPOSE

To investigate the causal relationship between acute postoperative endophthalmitis (POE) after cataract surgery and the biomaterial properties of the intraocular lens (IOLs) implanted.

METHODS

This retrospective cohort study included all patients who had undergone cataract surgery with IOL implantation at the Lyon Croix-Rousse University Hospital between 1st January 1994 and 31st December 2004. Details respecting the type of IOL implanted (material and manufacturer) were meticulously recorded. The number of patients presenting with POE within 6 weeks of cataract surgery was documented together with their medical characteristics. These data were then compared, and Fisher's exact test was used to establish the significance of any apparent associations.

RESULTS

Eight of the 5837 eyes manifested acute POE (0.14%). Seven of these were composed of polymethylmethacrylate (PMMA) and one of heparinized PMMA. Patients with PMMA IOLs carried a higher risk of developing POE than did those implanted with either heparinized PMMA (P=0.001), hydrophilic acrylic, or hydrophobic acrylic IOLs (P=0.002).

CONCLUSIONS

The incidence of acute POE after cataract surgery in our hospital is similar to that currently reported for other institutions in developed countries. Our results add further evidence that IOL material and type are factors contributing to the risk to develop an acute POE after cataract surgery, and that PMMA IOLs may be associated with an increased risk of POE.

Endophthalmitis and incision construction

PURPOSE OF REVIEW

The relationship between endophthalmitis after cataract extraction and type of incision has been under debate lately. In particular, clear corneal incisions have been connected with an increased incidence of postoperative endophthalmitis. This review discusses recent reports within this area.

RECENT FINDINGS

Experimental studies have demonstrated the poor integrity of a clear corneal incision under certain circumstances. A relationship between wound leakage the day after surgery and endophthalmitis has also been reported. Some large studies have shown an increase of endophthalmitis that in time coincide with the increasing use of clear corneal incision. One earlier randomized controlled study showed a higher incidence of endophthalmitis after clear corneal incision compared with superior incision. Other case series have shown an equal distribution of endophthalmitis between surgeries using different types of incision. Some studies point to the multifactorial nature of endophthalmitis and the importance of every step from antiseptic surgical field to postoperative treatment.

SUMMARY

There is no conclusive evidence of the relationship between clear corneal incision and endophthalmitis. It seems, however, that in certain situations clear corneal incision may play a role in the occurrence of endophthalmitis.

Risk factors for endophthalmitis following cataract surgery: a retrospective case–control study

To gain further knowledge of possible risk factors for the development of postoperative endophthalmitis (POE) following cataract surgery, a single-centre retrospective case-control study was conducted for 1994-2000. In total, 46292 cataract procedures were performed during the study period. Sixty cases of POE were noted and 240 control cases were selected at random. Parameters pertaining to patient history and to peri-operative technique and complications were analysed. The relative risk of POE was calculated using univariate analyses and multi-variate forward stepwise logistic regression. In the logistic regression analyses, three statistically significant parameters were found. The use of intracameral prophylaxis with cefuroxime as opposed to topical treatment alone, and performing phaco-emulsification instead of extra- or intracapsular cataract extraction appeared to be protective against POE. Silicone intra-ocular lenses carried a higher risk than heparin surface modified poly (methyl methacrylate) implants. In summary, the important finding of this study was the protective effect against POE of intracameral prophylaxis with cefuroxime compared with topical anti-infectives alone.