Prophylaxis for endophthalmitis following intravitreal injection: antisepsis and antibiotics

Prophylactic Intracameral Antibiotics and Endophthalmitis After Cataract Surgery

Importance

Although the effectiveness of intracameral antibiotics to prevent postoperative endophthalmitis is described, selective use of antibiotics combined with 1% povidone iodine disinfection might be equally effective and could lead to cost reduction and avoidance of unnecessary use of antibiotics.

Objective

To compare the incidence of postoperative endophthalmitis when 1% povidone iodine disinfection is applied in combination with selective intracameral antibiotics with the incidence after routine use of intracameral antibiotics in combination with 5% povidone iodine.

Design, Setting, and Participant

This was a retrospective cohort study using incidence data from the ongoing endophthalmitis register of the Rotterdam Eye Hospital, a specialized hospital providing both secondary and tertiary ophthalmological care, when intracameral antibiotics were used only during cataract procedures with occurrence of a posterior capsular tear in comparison with results from cohorts described in the literature where routine antibiotics were used. All patients who had cataract (phacoemulsification) surgery at the Rotterdam Eye Hospital between 1993 and 2022 were included. No cataract surgical procedures combined with other intraocular procedures were included.

Exposure

Povidone iodine disinfection and intracameral antibiotics during cataract surgery either routinely or only in case of posterior capsular tears.

Main Outcome and Measure

Postoperative endophthalmitis incidence.

Results

Postoperative endophthalmitis incidence after 56 598 cataract (phacoemulsification) surgical procedures in the Rotterdam Eye Hospital between 2016 and 2022 was 0.000 (95% CI, 0.000-0.000). A PubMed literature search until September 2023 with respect to the incidence of postoperative endophthalmitis after routine antibiotic prophylaxis yielded 37 publications with an overall postoperative endophthalmitis incidence of 0.000 (95% CI, 0.000-0.000).

Conclusions and Relevance

No difference was observed between the postoperative endophthalmitis incidence during the last 7 years in the Rotterdam Eye Hospital and the overall postoperative endophthalmitis incidence after routine intracameral antibiotics prophylaxis as described in the literature. Disinfection with 1% povidone iodine in combination with selective antibiotic prophylaxis may be equally effective as routine antibiotic use and 5% povidone iodine.

Comparing the in vitro efficacy of chlorhexidine and povidone-iodine in the prevention of post-surgical endophthalmitis

BACKGROUND

Intravitreal injections are a common ophthalmologic procedure. While infections following these injections are rare, they can lead to endophthalmitis, with potentially serious consequences. Various methods have been proposed to prevent endophthalmitis, including the use of antisepsis and antibiotics in patient preparation.

PURPOSE

To evaluate the antiseptic efficacy of aqueous chlorhexidine (CHX) and povidone-iodine (PI) when used alone and in combination with lidocaine gel (LG) in vitro.

METHODS

Two independent experimental trials were conducted. The first trial determined the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) of CHX and PI against six bacterial strains. The second trial evaluated the bactericidal efficacy of the antiseptic agents (CHX 0.1% and PI 5%) and their combination with LG against the same bacterial strains.

RESULTS

CHX was more effective than PI in reducing the number of colonies forming units (cfus) of the tested bacteria. The order in which the antiseptic and LG were administered affected their effectiveness, with CHX administered before LG resulting in greater reduction of bacterial growth.

CONCLUSIONS

CHX 0.1% is more effective than PI 5% as an antiseptic agent. Application of CHX and PI prior to the use of lidocaine gel results in a more effective reduction of microorganisms.

Antimicrobials and antiseptics: Lowering effect on ocular surface bacterial flora - A systematic review

Topical antimicrobials and antiseptics are used perioperatively to reduce the ocular surface bacteria flora (OSBF) that are involved in the development of post-operative infectious complications. However, their effectiveness is still a controversial topic. This systematic review, performed according to the PRISMA guidelines and registered in PROSPERO, aims to provide an overview of the efficacy of the agents currently used in peri-cataract surgery and -intravitreal injections (IVI) in lowering the OSBF. Although effective in lowering OSBF, perioperative topical antimicrobials are associated with the risk of resistance development, with no obvious additional benefit compared with topical antisepsis. Conversely, the effectiveness of topical antiseptics before cataract surgery and IVI is strongly supported. Based on the available evidence, perioperative antimicrobials are not recommended, whereas the perioperative use of antiseptics is strongly recommended as prophylactic treatment for lowering the infection due to OSBF. Post-operative antimicrobials may be considered in eyes at higher risk for infection.

Comparison of Endophthalmitis Rates after Alcohol-Based Chlorhexidine and Povidone-Iodine Antisepsis for Intravitreal Injections

OBJECTIVE

Intravitreal injections (IVIs) are the most frequently performed intraocular procedure in Canada. Povidone-iodine (PI) is the current gold standard for antisepsis for IVI and is widely used; chlorhexidine (CH) is a possible alternative antiseptic agent. This study aims to compare rates of endophthalmitis after IVI with 0.05% chlorhexidine with a 4% alcohol base antisepsis to rates of endophthalmitis after IVI with 10% PI antisepsis.

DESIGN

Retrospective cohort study.

SUBJECTS

Eyes that received IVI between May 2019 and October 2022 at a group retina practice in Edmonton, Canada.

METHODS

Eyes at a single center received focal conjunctival application of either 10% PI antisepsis or 0.05% CH in 4% alcohol antisepsis for 30 seconds before each IVI.

MAIN OUTCOME MEASURE

Rates of endophthalmitis between the PI and CH groups.

RESULTS

A total of 170 952 IVIs were performed during the study period. A total of 31 135 were performed using CH prophylaxis compared with 139 817 with PI prophylaxis. Among all IVIs there were 49 total cases of endophthalmitis, 29 in the PI group (0.021%) and 20 in the CH group (0.064%). There was a statistically significant difference in the rates of endophthalmitis between the 2 groups (P < 0.001). The odds ratio for developing endophthalmitis with CH antisepsis was 3.1 (95% confidence interval, 1.9-5.2) compared with PI antisepsis. There were increased odds of developing endophthalmitis with aflibercept injection compared with bevacizumab (odds ratio, 3.48; 95% confidence interval, 2.09-7.24).

CONCLUSIONS

There is a statistically significant difference in rates of endophthalmitis between alcohol-based CH and PI antisepsis for IVI in our patient population utilizing the methods discussed. In our center, alcohol-based CH is now considered a second-line antiseptic agent. Further studies are warranted to further assess the endophthalmitis rate utilizing these 2 antiseptic agents.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

In vivo antimicrobial activity of 0.6% povidone-iodine eye drops in patients undergoing intravitreal injections: a prospective study

To investigate the antimicrobial activity of a preservative-free 0.6% povidone-iodine eye drop as an antiseptic procedure in decreasing the conjunctival bacterial load in eyes scheduled for intravitreal treatment and to compare its efficacy to the untreated fellow eye used as the control group. Prospective cohort analysis in which 208 patients received preservative-free 0.6% povidone-iodine eye drops three times a day for three days before intravitreal injection. Before and after the prophylactic treatment, a conjunctival swab was collected from both the study eye and the untreated contralateral eye, used as control. The swab was inoculated on different culture media and the colony-forming units were counted. Bacteria and fungi were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Treatment with 0.6% povidone-iodine eye drops significantly reduced the conjunctival bacterial load from baseline (p < 0.001 for blood agar and p < 0.001 for chocolate agar) with an eradication rate of 80%. The most commonly isolated pathogen at each time-point and in both groups was coagulase-negative Staphylococci, isolated in 84% of the positive cultures. The study provides evidence about the effectiveness of 0.6% povidone-iodine eye drops treatment in reducing the conjunctival bacterial load in eyes scheduled for intravitreal treatment.

2018 Update on Intravitreal Injections: Euretina Expert Consensus Recommendations

Intravitreal injections (IVI) have become the most common intraocular procedure worldwide with increasing numbers every year. The article presents the most up-to-date review on IVI epidemiology and techniques. Unfortunately, important issues related to pre-, peri- and postinjection management lack randomized clinical trials for a final conclusion. Also, a great diversity of approaches exists worldwide. Therefore, expert consensus recommendations on IVI techniques are provided.

ENDOPHTHALMITIS AFTER INTRAVITREAL INJECTION: Role of Prophylactic Topical Ophthalmic Antibiotics

PURPOSE

To determine the rate of postintravitreal injection endophthalmitis and to assess microbiological features and outcomes with and without the use of peri-intravitreal injection topical ophthalmic antibiotics.

METHODS

Consecutive series of endophthalmitis cases retrospectively identified after intravitreal injection at a multicenter, retina-only referral practice (Retina Consultants of Houston) from January 1, 2011 to December 31, 2014. Prophylactic peri-intravitreal injection topical antibiotics were routinely used during the initial 12-month period (January 1, 2011-December 31, 2011) and not used in the final 24-month period (January 1, 2013-December 31, 2014). Main outcome measures were incidence of endophthalmitis, microbiology results, treatment strategies, and visual outcomes.

RESULTS

Of 90,339 intravitreal injections, 30 cases of endophthalmitis were identified (endophthalmitis rate = 0.033%; 95% confidence interval, 0.021-0.045%; or approximately 1 of 3,011 intravitreal injections). The most common organisms isolated were coagulase-negative staphylococci (n = 10, 33%), followed by Streptococcus mitis (n = 2, 7%). Fourteen cases (47%) were culture negative. Peri-intravitreal injection topical antibiotic prophylaxis did not decrease the rate of endophthalmitis (0.035% [95% CI, 0.007-0.064%] with antibiotic use versus 0.021% [95% CI, 0.008-0.033%] without antibiotic use; P = 0.261).

CONCLUSION

The risk of endophthalmitis after intravitreal injection remains low, with coagulase-negative staphylococci and Streptococcus mitis the most common bacterial isolates identified. Prophylactic peri-intravitreal injection topical ophthalmic antibiotic use did not decrease the endophthalmitis rate.

Infectious and sterile endophthalmitis after intravitreal injections: differential diagnosis, prevention, treatment

Endophthalmitis is a rare but extremely severe complication of different intraocular procedures. In the article, we analyze world literature data on prevalence, differential diagnosis, prevention methods, and treatment of endophthalmitis after intravitreal injections.

Aqueous Chlorhexidine for Intravitreal Injection Antisepsis: A Case Series and Review of the Literature

PURPOSE

To determine the incidence of endophthalmitis in a large clinical series using aqueous chlorhexidine for antisepsis before intravitreal injection and to review the ophthalmic literature regarding chlorhexidine efficacy and safety.

DESIGN

Multicenter retrospective case series.

PARTICIPANTS

All patients receiving intravitreal injections from 7 retinal specialists.

METHODS

An audit of intravitreal injections performed by retinal specialists who exclusively used aqueous chlorhexidine 0.05% or 0.1% for prophylaxis of infective endophthalmitis was undertaken. The incidence of endophthalmitis was determined from August 1, 2011, to February 28, 2015. A literature review was performed to critically appraise the ocular safety and efficacy of aqueous chlorhexidine.

MAIN OUTCOME MEASURES

Incidence of endophthalmitis after intravitreal injections.

RESULTS

A total of 40 535 intravitreal injections were performed by 7 retinal specialists across 3 centers. Chlorhexidine was well tolerated, and only 1 patient with a suspected allergic reaction was noted. Three cases of endophthalmitis were identified with 1 culture-positive case. The 0.0074% (1 in 13 512) per-injection rate of endophthalmitis in this series compares favorably with previous series in which povidone-iodine has been used.

CONCLUSIONS

Aqueous chlorhexidine was associated with a low rate of postinjection endophthalmitis and was well tolerated by patients.

Incidence of Endophthalmitis after Intravitreal Anti-vascular Endothelial Growth Factor: Experience in Saudi Arabia

PURPOSE

To report the incidence of endophthalmitis, the clinical and microbiological aspects, after intravitreal (IVT) injection of anti-vascular endothelial growth factor.

METHODS

A chart review was performed of patients diagnosed with endophthalmitis after receiving IVT injections of bevacizumab (Avastin) and ranibizumab (Lucentis) presenting to King Khaled Eye Specialist Hospital (KKESH) from May 2006 to December 2012. Endophthalmitis was diagnosed clinically as an intraocular infection with vitreous involvement that required treatment with IVT antibiotics or had undergone pars plana vitrectomy (PPV) to remove the suspected microorganism. Main outcome measures were the incidence of endophthalmitis and the clinical and microbiological features.

RESULTS

Seven cases of endophthalmitis were identified, there was 1 (0.004%) case of endophthalmitis of 22674 IVT injections performed at KKESH. All cases were after IVT bevacizumab. Three (42.85%) cases were culture-positive and caused by Staphylococcus epidermidis. The initial management was vitreous tap and IVT injection of antibiotics followed by PPV in 6 (85.7%) cases. One (14.3%) case underwent evisceration. Visual acuity improved at last visit in only 2 (28.6%) cases. The rate of endophthalmitis was 0.0004% for bevacizumab.

CONCLUSIONS

The rate of endophthalmitis after IVT bevacizumab and ranibizumab was very low. We recommend following a standardized injection protocol, adherence to sterile techniques, and proper patient follow-up are determinant factors for low incidence rates. In addition, endophthalmitis after IVT bevacizumab and ranibizumab have poor visual outcomes despite prompt treatment.

Antibioprophylaxis in Prevention of Endophthalmitis in Intravitreal Injection: A Systematic Review and Meta-Analysis

Despite endophthalmitis being the most feared complication, antibioprophylaxis remains controversial in intravitreal injections. Therefore, we conducted a systematic review and meta-analysis on the effects of antibioprophylaxis in intravitreal injections in the prevention of endophthalmitis. The PubMed, Cochrane Library, Embase and Science Direct databases were searched for studies comparing groups with and without antibiotics in intravitreal injection, with the use of the following keywords: "antibiotic*", "endophthalmitis" and “intravitreal injection*”. To be included, studies needed to specify number of participants and number of endophthalmitis within each group (with and without antibiotics). We conducted meta-analysis on the prevalence of clinical endophthalmitis including both culture-proven and culture negative samples. Nine studies were included. A total of 88 incidences of endophthalmitis were reported from 174,159 injections (0.051% i.e., one incidence of endophthalmitis for 1979 injections). Specifically, 59 incidences of endophthalmitis were reported from 113,530 injections in the group with antibiotics (0.052% or one incidence of endophthalmitis for 1924 injections) and 29 incidences of endophthalmitis from 60,633 injections in the group without antibiotics (0.048% or one endophthalmitis for 2091 injections). Our meta-analysis did not report a significant difference in the prevalence of clinical endophthalimitis between the two groups with and without topical antibiotics: the odds ratio of clinical endophthalimitis was 0.804 (CI95% 0.384–1.682, p = 0.56) for the antibiotic group compared with the group without antibiotics. In conclusion, we performed the first large meta-analysis demonstrating that antibioprophylaxis is not required in intravitreal injections. Strict rules of asepsis remain the only evidence-based prophylaxis of endophthalmitis. The results support initiatives to reduce the global threat of resistance to antibiotics.

Endophthalmitis following intravitreal anti-vascular endothelial growth factor (VEGF) injection: a comprehensive review

The purpose of this review is to report and summarize previously reported studies and assess many of the individual steps of the intravitreal injection procedure's possible effect on the prevention of endophthalmitis. The pooled endophthalmitis rate from 20 large retrospective case series of anti-VEGF injections was 144/510,396 (0.028%; 1/3,544). Injections may be performed in an office-based location or in an operating room (OR) and low rates of endophthalmitis can be achieved in either location with careful attention to asepsis. Pre- or post-injection topical antibiotics have not been shown to be effective, and could select for more virulent microorganisms. Povidone-iodine prior to injection is accepted as the gold-standard antiseptic agent, but aqueous chlorhexidine may be an alternative. Antisepsis before and after gel or subconjunctival anesthetic is suggested. The preponderance of Streptococcal infections after intravitreal injection is discussed, including the possible role of aerosolization, which can be minimized by using face masks or maintaining silence. As with other invasive procedures in medicine, the use of sterile gloves, following adequate hand antisepsis, may be considered. Control of the eyelashes and lid margin is required to avoid contamination of the needle, but this can be achieved with or without a speculum. Techniques to minimize vitreous reflux have not been shown to reduce the risk of endophthalmitis. Same day bilateral injections should be performed as two separate procedures, preferably using drug from different lots, especially when using compounded drugs.

Safety study of 38,503 intravitreal ranibizumab injections performed mainly by physicians in training and nurses in a hospital setting

PURPOSE

To evaluate and to compare the safety of intravitreal ranibizumab injections performed by physicians and nurses at a single large hospital clinic in Denmark during 5 years.

DESIGN

Retrospective, interventional, non-comparative study.

METHODS

SETTING

All eyes that underwent a protocolized ranibizumab injection procedure performed in an operating room mainly by nurses and physicians in their first year of ophthalmology training.

STUDY POPULATION

A total of 4623 eyes in 3679 patients with subretinal neovascularization secondary to a variety of retinal diseases, mainly neovascular AMD treated with intravitreal therapy (IVT) at the Glostrup Hospital from January 1, 2007 to December 31, 2011 with a mean follow-up of 12.2 months (95% confidence interval: 11.9-12.6).

MAIN OUTCOME MEASURES

Frequency of endophthalmitis, traumatic cataract, intraocular haemorrhage and retinal detachment from 2007 to 2012.

RESULTS

Overall, 38,503 intravitreal ranibizumab injections were performed in 4623 eyes. Injections were performed by nurses (32.5%), ophthalmology residents (61.3%) and vitreoretinal surgeons (6.2%). Severe complications to treatment were observed in 17 eyes: Endophthalmitis (14 eyes, 0.36 ‰ of injections whereof seven cases were culture-positive), anterior uveitis (one eye, 0.026 ‰), traumatic cataract (one eye, 0.026 ‰) and rhegmatogenous retinal detachment (one eye, 0.026 ‰). Retinal pigment epithelial tears were registered in 14 eyes in 14 subjects within the first year of treatment with ranibizumab. Of the 14 cases of endophthalmitis, seven occurred within a period of 5 weeks in 2010 when occasionally abnormal needle outflow resistance prompted the needle replacement in the operating room. No drug-related adverse events were recorded.

CONCLUSIONS

Intravitreal ranibizumab injection performed by nurses and physicians without preinjection topical antibiotics was associated with a rate of injection-related adverse events of 0.44 ‰.

No cases of endophthalmitis after 20,293 intravitreal injections in an operating room setting

BACKGROUND

Intravitreal injection has become a common procedure worldwide. A rare, but sight threatening, complication is bacterial endophthalmitis that has a poor visual prognosis. To identify practices that minimize the risk of endophthalmitis, the setting of a Danish University hospital is described.

METHODS

A review of the intravitreal injection database of the department. All injections were performed in a positive pressure ventilated operating room under sterile conditions. The treating physicians wore face mask, the conjunctiva was irrigated twice with 5% povidone-iodine preoperatively, and topical tobramycin was applied immediately after the injection.

RESULTS

The authors have performed a total of 20,293 injections were performed in 2,575 eyes. No cases of proven or suspected endophthalmitis were identified corresponding to a risk of 0% (95% confidence interval, 0-0.019) per injection and 0% (95% confidence interval, 0-0.15%) per patient. Approximately 7,000 injections, all in patients without diabetes, were treated without a course of topical antibiotics after the injection.

CONCLUSION

The department has had the lowest rate of endophthalmitis after intravitreal injections in the current literature. Several factors that could have contributed to the positive result are highlighted. Omitting a postoperative course of topical antibiotic appears safe in patients without diabetes.

Endophthalmitis Associated with Intravitreal Anti-Vascular Endothelial Growth Factor Injections

The use of anti-vascular endothelial growth factor (VEGF) agents has led to a dramatic increase in the number of intravitreal injections. Endophthalmitis remains a rare but potentially vision-threatening complication of intravitreal injections. Recent large series have estimated this risk to be about one in 3,000 injections or less. Bevacizumab, which is generally prepared by a compounding pharmacy, is associated with additional risks of contamination. Although endophthalmitis cannot be prevented in all cases, certain risk reduction strategies have been proposed, including the use of an eyelid speculum, povidone iodine, avoidance of needle contact with the eyelid margin or eyelashes, and avoidance of routine post-injection antibiotics. Despite these precautions, some patients will develop endophthalmitis following intravitreal anti-VEGF injections, and outcomes may be poor despite prompt and appropriate therapy.

Povidone-iodine contact time and lid speculum use during intravitreal injection

PURPOSE

To determine the time necessary for 5% povidone-iodine (PI) to cause a significant reduction in colony-forming units and whether a lid speculum increases the conjunctival flora.

METHODS

This was a prospective randomized study of 131 eyes undergoing intravitreal injection. Conjunctival samples were collected in a prospective protocol at three points before intravitreal injection: (1) no intervention (baseline), (2) after placement of a lid speculum, and (3) after treatment with 5% PI. Participants were randomized into three different PI exposure intervals. Cultures were incubated for 6 days, and the resulting colony-forming units were tallied for each intervention.

RESULTS

Use of 5% PI caused significant decrease in the number of colony-forming units (P < 0.0001). Exposure to PI for 15 seconds did not cause a significant reduction in conjunctival bacteria (P = 0.08), but a significant reduction was observed after 30 seconds of exposure and beyond (P = 0.0003). Placement of a lid speculum did not result in a significant increase or decrease in the number of colony-forming units when compared with baseline (P = 0.47).

CONCLUSION

The use of 5% PI causes a significant reduction in bacterial colonies, and 30 seconds of exposure appears to be an adequate time to decrease conjunctival bacterial counts. Lid speculum use before intravitreal injection does not affect the overall conjunctival flora.

Streptococcus endophthalmitis outbreak after intravitreal injection of bevacizumab: one-year outcomes and investigative results

PURPOSE

To report the 1-year clinical outcomes of an outbreak of Streptococcus endophthalmitis after intravitreal injection of bevacizumab, including visual acuity outcomes, microbiological testing, and compound pharmacy investigations by the Food and Drug Administration (FDA).

DESIGN

Retrospective consecutive case series.

PARTICIPANTS

Twelve eyes of 12 patients who developed endophthalmitis after receiving intravitreal bevacizumab prepared by a single compounding pharmacy.

METHODS

Medical records of patients were reviewed; phenotypic and DNA analyses were performed on microbes cultured from patients and from unused syringes. An inspection report by the FDA based on site visits to the pharmacy that prepared the bevacizumab syringes was summarized.

MAIN OUTCOME MEASURES

Visual acuity, interventions received, time to intervention, microbiological consistency, and FDA inspection findings.

RESULTS

Between July 5 and 8, 2011, 12 patients developed endophthalmitis after intravitreal bevacizumab from syringes prepared by a single compounding pharmacy. All patients received initial vitreous tap and injection, and 8 patients (67%) subsequently underwent pars plana vitrectomy (PPV). After 12 months follow-up, outcomes have been poor. Seven patients (58%) required evisceration or enucleation, and only 1 patient regained pre-injection visual acuity. Molecular testing using real-time polymerase chain reaction, partial sequencing of the groEL gene, and multilocus sequencing of 7 housekeeping genes confirmed the presence of a common strain of Streptococcus mitis/oralis in vitreous specimens and 7 unused syringes prepared by the compounding pharmacy at the same time. An FDA investigation of the compounding pharmacy noted deviations from standard sterile technique, inconsistent documentation, and inadequate testing of equipment required for safe preparation of medications.

CONCLUSIONS

In this outbreak of endophthalmitis, outcomes have been generally poor, and PPV did not improve visual results at 1-year follow-up. Molecular testing confirmed a common strain of S. mitis/oralis. Contamination seems to have occurred at the compounding pharmacy, where numerous problems in sterile technique were noted by public health investigators.

Minimizing the endophthalmitis rate following intravitreal injections using 0.25% povidone-iodine irrigation and surgical mask

BACKGROUND

To examine the efficacy of complying with an infection control manual for intravitreal injection of anti-vascular endothelial growth factor (VEGF) preparations in reducing the rate of endophthalmitis.

METHODS

We retrospectively reviewed intravitreal anti-VEGF injections conducted by vitreoretinal specialists at the outpatient injection room of a single university hospital between July 2009 and July 2012. The injections were conducted following an infection control manual established by our department. Doctors and nurses wore surgical masks, and disinfected the patient's eyelid skin with 10% povidone-iodine and then the conjunctiva with 0.25% povidone-iodine. After putting a drape on the patient's face, a lid speculum was placed. The conjunctival surface was again washed with 5 ml of 0.25% povidone-iodine. After waiting at least 30 seconds, intravitreal injection was performed through povidone-iodine. Following injection, the injection site was again washed with 5 ml of 0.25% povidone-iodine. Patients were treated with topical levofloxacin 4 times a day for 3 days before and after the injection.

RESULTS

A total of 15,144 injections comprising 548 injections of pegaptanib sodium, 846 injections of bevacizumab, and 13,750 injections of ranibizumab were performed. During this period, no case of suspected or proven infectious endophthalmitis occurred. The endophthalmitis rate was 0 per 15,144 injections, (95% confidence interval, 0.0-0.0%).

CONCLUSION

The results suggest that endophthalmitis can be reduced to a minimum by preventing normal flora of the conjunctiva and bacteria in the oral cavity from entering the vitreous. For this purpose, an infection control manual that requires nurses and doctors to wear surgical mask and drape the patient's face, irrigate the conjunctiva with 0.25% povidone-iodine and wait at least 30 seconds before performing intravitreal injection is useful.