Prophylactic intracameral cefuroxime. Evaluation of safety and kinetics in cataract surgery

Endophthalmitis after cataract surgery and effect of different intracameral antibiotic regimes in Sweden 2011-2017: national registry study

PURPOSE

To study the incidence, predictive factors, etiology, and visual consequences of postoperative endophthalmitis (PE) in relation to 3 intracameral (IC) antibiotic regimes.

SETTING

Swedish National Cataract Register entries from 2011 through 2017.

DESIGN

Observational retrospective study.

METHODS

PE incidence, influencing factors, bacteriology, and visual outcome were analyzed regarding the 3 major prophylactic IC protocols.

RESULTS

The overall incidence of PE was 0.023% or 177 cases in 764 513 cataract procedures. Analyzed per IC regime, the rates of PE were 0.024% (126 cases in 514 916 surgeries) for cefuroxime, 0.020% (25 cases in 122 340 surgeries) for moxifloxacin, and 0.017% (20 cases in 121 045 surgeries) for combined cefuroxime-ampicillin. Incidences were not statistically significantly different from one another. Gram-positive bacteria caused 89.0% of culture positive cases. Enterococci as pathogens were significantly more frequent with IC cefuroxime than with moxifloxacin, P = .006, or cefuroxime-ampicillin, P < .001, while streptococci other than enterococci were more common with moxifloxacin than with cefuroxime, P < .001. Bacterial susceptibility to the given antibiotics was demonstrated in 21.3% of PE cases treated with cefuroxime, which was statistically significantly lower than proportions found with cefuroxime-ampicillin, 60.0%, P = .015, or with moxifloxacin, 88.2%, P < .001. Visual outcome worse than 20/200 was similar in the groups ranging from 42.0% to 53.7%.

CONCLUSIONS

No statistically significant differences in PE incidence or visual outcome results between treatment groups were demonstrated. However, differences in etiology and bacterial sensitivity were found between the prophylactic IC treatments.

Role of Prophylactic Oral Antibiotics in the Prevention of Post-cataract Surgery Acute Infective Endophthalmitis

Purpose To evaluate the role of perioperative oral antibiotics in the prevention of acute infective endophthalmitis (IE) after cataract surgery. Methods A prospective cohort study of patients older than 18 years of age undergoing uncomplicated phacoemulsification was conducted. Group A was given post-op oral ciprofloxacin for three days, whereas Group B was not. Both groups received 5% povidone-iodine (PVI) preparation for five minutes in the conjunctival cul-de-sac, and intracameral (IC) 0.5% moxifloxacin was administered at the end of the procedure as prophylaxis. The minimum post-op follow-up period was six weeks. Results Out of 2161 patients, 859 (39.8%) were included in Group A, and 1302 (60.2%) were included in Group B. No significant difference in anterior chamber (AC) reaction was found on day 1 (p = 0.67), day 14 (p = 0.03), or day 45 (p = 0.1). One patient developed acute post-op IE (0.04%) and two patients developed toxic anterior segment syndrome (TASS) from Group A. The non-oral antibiotic group had no serious complications. Conclusion Perioperative oral antibiotic use in routine clinical practice is not recommended for the prevention of acute post-op IE. Pre-op conjunctival PVI 5% for five minutes and IC moxifloxacin at the end of surgery were proven to be effective prophylactic measures in our study.

Management of patients undergoing cataract surgery: An Italian survey

PURPOSE

To investigate the management of patients undergoing cataract surgery in Italy.

SETTING

Italian ocular surgeons, members of the Italian Association of Cataract and Refractive Surgery (AICCER), were invited to participate to this survey.

DESIGN

Participants had to respond to a questionary including a series of practical questions concerning the management of patients undergoing cataract surgery.

METHODS

A designed questionnaire explored the main issues concerning the practical problems involved in managing patients undergoing cataract surgery. The questionnaire was sent by e-mail and analyzed by descriptive statistics.

RESULTS

Preoperative prophylaxis was performed by most surgeons. After surgery, several products were used, even simultaneously. Fixed antibiotic-corticosteroid combination (87.2%; 89) and NSAIDs (88.2; 90) were chosen as the most commonly used drug classes. The average duration of prescribed post-surgical therapies was more than two weeks for 52.9% (54) of participants, two weeks for 29.4% (30), and only one week for 5.9% (6).

CONCLUSION

This survey confirmed a discrete adherence to the main guidelines but at the same time highlights a discrete inhomogeneity in the use of medications, duration of treatments, and follow-up visits. For this reason, it is appropriate to continue updating and implementing the guidelines and educational pathways. This thought is consistent with the Precision Medicine approach. Every patient should be carefully evaluated to determine the best medication, dosage, and duration. A Personalized Medicine strategy is used on a single patient to optimize treatment clinical efficacy while minimizing side effects.

Impact on corneal morphology after cataract surgery with intracameral moxifloxacin in neglected hard cataracts

AIM

To evaluate corneal morphology after use of 0.5% intracameral moxifloxacin (ICM) in cataract surgery in patients who presented late with hard cataracts.

METHODS

Cross-sectional study conducted from June-2021 to December-2021 at a tertiary eye-care center. 90 patients over 60 years with high-risk characteristics for Covid-19, who presented late with higher grades of nuclear-sclerosis (NS), were included. They underwent phacoemulsification and 0.5%moxifloxacin (0.1 ml) was injected intracamerally at the end of surgery. Best-corrected visual acuity (BCVA), intraocular pressures (IOP), endothelial cell density (ECD), coefficient of variation in cell-area (CoV), hexagonality (Hex) and central corneal thickness (CCT) were measured preoperatively and postoperatively on day1, day7 and day30. Statistical analysis was done by Anova test. p-value<0.05 was considered significant.

RESULTS

Mean age of presentation was 65.26±8.3 years. Mean preoperative BCVA (1/60-to-6/60), IOP (16.7±2.3 mm of Hg), CCT (523.93±39.6µ), ECD (2547±302.08cells/mm2), Hex (47.04±5.7%) and CoV (37.57±3.9) changed to BCVA (6/9-to-6/6), IOP (17.5±2.1 mm of Hg), CCT (538.42±36.9µ), ECD (2388.40±339.25cells/mm2), Hex (44.44±5.6%) and CoV (39.09±4.5) at day30 postoperative. Average rate of change at day30 was increase in CCT (2.89%), ECD loss (6.4%), decrease in Hex (4.9%) and increase in CoV (4.6%), though clinically insignificant. No case of endophthalmitis or toxic-anterior segment syndrome seen.

CONCLUSION

0.5% moxifloxacin (0.1 ml) is safe as intracameral antibiotic to prevent postoperative infection in high-risk patients. The reported changes in the corneal parameters were within the range of any routine surgeries of hard senile cataracts. No specific effect could be attributed to ICM.

Acute Serous Retinal Detachment after the Same Operating Session of Uncomplicated Cataract Surgeries: A Case Series

PURPOSE

To report four cases of acute serous retinal detachment (ASRD) after the same operating session of uncomplicated cataract surgeries.

METHODS

In this case series, data of patients who developed ASRD after uncomplicated phacoemulsification with intraocular lens implantation during the same operating session were collected. Diagnosis was made on the first postoperative day, when all patients had a very low best-corrected visual acuity (BCVA), despite a good aspect of the anterior segment, without significant keratopathy and with only trace cells in the anterior chamber. Spectral-domain optic coherence tomography (SD-OCT) revealed serous retinal detachment with subretinal fluid accumulation in the macular area. Patients received a parabulbar injection of 40 mg/mL triamquinolone in addition to usual the postoperative topical treatment of 0.1% dexamethasone and 0.3% netilmicin eye drops. Patients were examined postoperatively on days 1, 3, 7, and 1 month. BCVA and central foveal thickness (CFT) measured by SD-OCT were evaluated at each visit. A relationship between demographics, preoperative ocular conditions, systemic diseases, parameters of surgery, and the development of ASRD was analyzed.

RESULTS

After a single operating session of 10 uneventful cataract surgeries, operated by the same expert surgeon, on postoperative day 1, ASRD was detected in 4 patients (3 male, 1 female; mean age 71 ± 4.1 years). Preoperatively, the mean BCVA was 0.6 ± 0.1 decimals and mean CFT was 191.3 ± 13.7 µm. On the first postoperative day, mean BCVA was 0.01 ± 0.1 decimals, and all eyes had serous retinal detachment, with a mean CFT of 682.0 ± 97.4 µm. On the following visits, BCVA improved and CFT reduced significantly. On day 7, BCVA was at least 0.7 decimals in all eyes, with complete reabsorption of subretinal fluid. At 1 month, mean BCVA was 1.0 ± 0.0 decimals and no eye had recurrence of serous retinal detachment, with a mean CFT of 202.3 ± 26.7 µm. No relevant data were found on other parameters investigated.

CONCLUSION

Acute serous retinal detachment is a rare event that can occur after uncomplicated phacoemulsification, which in our cases, resolved in a few days without recurrence.

High dose cefuroxime causing retinal toxicity in a patient undergoing trabeculectomy

PURPOSE

To present a case of severe retinal toxicity secondary to high dose intracameral cefuroxime administered during trabeculectomy glaucoma surgery. We describe the clinical features and management, and describe serial multimodal imaging and electrophysiological findings. Intracameral cefuroxime (ICC) and subconjunctival cefuroxime (SCC) are routinely administered during ocular surgeries to prevent postoperative endophthalmitis. Cefuroxime toxicity with both standard (1mg/0.1mL) and high doses of ICC (2-100mg) and SCC (31.25mg) have been reported. To the best of our knowledge, this is the first report of cefuroxime retinal toxicity in trabeculectomy surgery, which is of particular significance because of the possible differences in pharmacokinetics within the eye.

OBSERVATIONS

A 69-year-old male with primary open-angle glaucoma, underwent right trabeculectomy, augmented with mitomycin C (0.2mg/mL). The patient inadvertently received cefuroxime 12.5mg/0.1mL as an intracameral rather than a subconjunctival injection. Within 4 hours, the error was discovered and the patient underwent immediate anterior chamber (AC) washout. His right best-corrected visual acuity was hand movements, and he rapidly developed uveitis including AC cells and moderate vitritis and haze. Optical coherence tomography (OCT) demonstrated serous macular detachment, characteristic schisis-like changes in the outer nuclear layer and ellipsoid zone disruption. Multi-focal electroretinograms (ERG) identified deficits undetected by full-field ERG. He was successfully managed with intensive local topical corticosteroid, non-steroidal therapy and peri-ocular corticosteroid injection.

CONCLUSIONS AND IMPORTANCE

As ICC and SCC are routinely used in intra-ocular surgery to prevent endophthalmitis, ophthalmologists need to be aware of this potential complication and consider this in patients with unexplained reduced vision post-operatively. Theatre teams need to be vigilant about potential dilution and administration errors to ensure that the correct concentration and volume of cefuroxime is given via the correct route. We highlight the risks of high dose intracameral injection, including uveitis and retinal toxicity, and the utility of serial OCT, and full-field and multi-focal ERGs in this condition. We report a favourable outcome with significant and rapid improvement in retinal structure and function observed during follow-up. A literature review of the condition is presented.

A One-Week Course of Levofloxacin/Dexamethasone Eye Drops: A Review on a New Approach in Managing Patients After Cataract Surgery

A new fixed-dose combination of dexamethasone and levofloxacin eye drops has recently been approved for the prevention and treatment of inflammation, and the prevention of infection associated with cataract surgery in adults. This combination has been developed to respond to a series of unmet needs in the practical management of patients undergoing cataract surgery. Namely, despite updated guidelines, many ophthalmologists employ protocols mainly based on their personal experience. As a result, the choice of drugs, treatment duration, and drug association is not evidence-based medicine (EBM)-oriented. In addition, antibiotic resistance may occur since antibiotics are used for an extended length of time, even with tapering. Corticosteroids are also prescribed for prolonged periods, frequently without follow-up. Therefore, patient adherence to postsurgical self-care is low, and mainly affects older patients who are the majority undergoing cataract surgery. In both rabbit and human trials, it has been demonstrated that both active ingredients penetrate the ocular system without pharmacokinetic interaction between the two. The concentrations of both ingredients in aqueous humor after their ocular instillation are high enough at the site of action to carry out their expected potent anti-inflammatory and antibiotic activity. Tested in a pivotal study aimed at investigating efficacy and safety of the intended indication, the mixture/compound was non-inferior to a 2-week treatment with dexamethasone/tobramycin in preventing or reducing inflammation and in preventing infection when administered for 1 week, followed by the administration of dexamethasone alone for another week. The outcomes obtained by this study suggest that a 1-week course of levofloxacin/dexamethasone eye drops is sufficient to resolve inflammation and prevent infection in patients undergoing cataract surgery. In addition, this study underlines that a follow-up visit after 1 week allows for a decision about whether to stop or continue a treatment in patients still experiencing symptoms or inflammation. In conclusion, this new dose combination could represent a turning point in managing patients after cataract surgery, while mostly avoiding antibiotic resistance and improving treatment adherence.

Ocular toxicity after inadvertent overdose of intracameral cefuroxime during cataract surgery

PURPOSE

To describe intracameral toxic effects of cefuroxime at a higher dose than recommended in cataract surgery.

METHODS

Retrospective study of 8 eyes of 8 patients who inadvertently received 12.5 mg/0.1 ml of intracameral cefuroxime due to a dilution error, at the end of the cataract surgery. All patients underwent a strict ophthalmology follow-up for 6 months.

RESULTS

All patients presented with a marked anterior segment inflammation with corneal oedema that resolved completely in all cases (between 5 days and 3 months). At 6 months of follow-up a statistically significant difference was found in the corneal endothelial cell density when compared with the fellow eye (P = .038), being <1000 cells/mm² in 3 cases. Three patients (37.5%) showed early macular oedema, with subfoveal ellipsoid layer disruption in one case as a permanent sequel. One patient developed an optic neuropathy with associated afferent pupillary defect.

CONCLUSIONS

Although 1 mg/0.1 ml of intracameral cefuroxime has been shown to reduce the incidence of endophthalmitis, its overdose can have potentially toxic eye effects in both anterior and posterior segments.

Endophthalmitis Prophylaxis Failures in Patients Injected With Intracameral Antibiotic During Cataract Surgery

PURPOSE

To estimate the association of cefuroxime and moxifloxacin in relation to the occurrence of endophthalmitis following phacoemulsification cataract surgery.

DESIGN

Retrospective clinical cohort study.

METHODS

We studied patients with noncomplex phacoemulsification cataract surgery in Kaiser Permanente Northern California during 2014-2019. Data were obtained for acute, postoperative endophthalmitis within 90 days of phacoemulsification, including culture and antibiogram results, intracameral and topical antibiotic agent, and dose. In a post hoc analysis, we also examined preoperative anterior chamber depth (ACD) and postoperative anterior chamber volume (ACV).

RESULTS

Of 216,141 surgeries, endophthalmitis occurred in 0.020% of moxifloxacin-injected eyes and 0.013% of cefuroxime eyes (relative risk 1.62 with 95% CI 0.82-3.20, P = .16). Of the 34 (0.016%) cases of endophthalmitis, cefuroxime 1 mg was injected into 13 eyes and moxifloxacin 0.1% into 21 eyes. Organisms with antibiograms were identified in 12 (35%) cases. Of these, bacteria recovered from cefuroxime-injected eyes were resistant to cefuroxime in all cases (4/4), with Enterococcus comprising half of these. In eyes injected with moxifloxacin 0.1%, 6 out of 7 organisms were sensitive to moxifloxacin injected with 0.1 mL and in 1 eye injected with 1 mL. Streptococcus was the most common organism recovered (6/9) in moxifloxacin-injected eyes. Preoperative ACD and postoperative calculated ACV were higher in eyes injected with moxifloxacin.

CONCLUSIONS

Endophthalmitis cases with positive cultures were generally related to organism resistance in cefuroxime eyes but to sensitive organisms in moxifloxacin eyes. Moxifloxacin doses may have been insufficient in eyes with larger ACV.

Ocular toxicity after inadvertent overdose of intracameral cefuroxime during cataract surgery

PURPOSE

To describe intracameral toxic effects of cefuroxime at a higher dose than recommended in cataract surgery.

METHODS

Retrospective study of 8 eyes of 8 patients who inadvertently received 12.5mg/0.1ml of intracameral cefuroxime due to a dilution error, at the end of the cataract surgery. All patients underwent a strict ophthalmology follow-up for 6 months.

RESULTS

All patients presented with a marked anterior segment inflammation with corneal oedema that resolved completely in all cases (between 5 days and 3 months). At 6 months of follow-up a statistically significant difference was found in the corneal endothelial cell density when compared with the fellow eye (P=.038), being<1000 cells/mm2 in 3 cases. Three patients (37.5%) showed early macular oedema, with subfoveal ellipsoid layer disruption in one case as a permanent sequel. One patient developed an optic neuropathy with associated afferent pupillary defect.

CONCLUSIONS

Although 1mg/0.1ml of intracameral cefuroxime has been shown to reduce the incidence of endophthalmitis, its overdose can have potentially toxic eye effects in both anterior and posterior segments.

Incremental effect of topical and oral moxifloxacin administration with surgical intracameral prophylaxis

OBJECTIVE

To determine how supplemental perioperative topical or oral moxifloxacin administration impacts anterior chamber (AC) antibiotic concentrations beyond those achieved by intracameral (IC) administration alone for postoperative endophthalmitis (POE) prophylaxis.

DESIGN

Mathematical modeling.

METHODS

The mathematical model developed by Arshinoff, Modabber, and Felfeli was adapted to calculate all reported data. A literature review of pharmacokinetic data for topical and oral moxifloxacin was used to inform the expansion of the model.

RESULTS

Our previously constructed IC model yields a dose of moxifloxacin in the AC sufficient to confer bactericidal coverage against the most common POE pathogen, methicillin-sensitive Staphylococcus aureus (MSSA), for ∼40 hours postoperatively. Topical 0.5% moxifloxacin eye drops alone, administered every 4 or 6 hours, achieve an AC concentration just above or at the mutant prevention concentration (MPC) for MSSA, respectively, whereas 8-hour dosing produces levels generally below the MPC. Combining topical moxifloxacin with IC increases the AC concentration above IC alone only after 20 or more hours and maintains the AC concentration at, or just below, the MPC for MSSA for as long as the drops are continued. Combined perioperative oral moxifloxacin with IC increases AC levels over IC alone only after 16 hours and maintains the AC concentration above the MPC for MSSA for an additional 5 hours, owing to the systemic reservoir.

CONCLUSIONS

The addition of topical or oral moxifloxacin supplemental to IC can extend the duration of bactericidal coverage for the most common, but not the most resistant POE-causing pathogens.

Effect of Intracameral Cefuroxime on Graft Endothelial Cells in Descemet Membrane Endothelial Keratoplasty: A Comparative Study

Purpose: To evaluate the effect of intracameral cefuroxime on graft endothelial cell loss after simple Descemet Membrane Endothelial Keratoplasty (DMEK) and combined DMEK and cataract surgery.Materials and Methods: Single-center retrospective comparative analysis. One hundred and three patients were included, 31 in the cefuroxime group and 72 in the non-cefuroxime (NC) group. Best Spectacle-Corrected Visual Acuity (BSCVA), endothelial cell density (ECD) of the graft measured by specular microscopy, and the recipient's pachymetry were recorded pre-operatively and at 1, 3, and 6 months after surgery.Results: In the cefuroxime group, BSCVA was 0.22 ± 0.27 LogMAR, 0.15 ± 0.24 LogMAR and 0.07 ± 0.22, respectively, at 1, 3, and 6 months after surgery with no significant differences found when compared to the NC group (p > .05). Anatomical outcomes were similar as mean pachymetry decreased from 599 ± 51 µm preoperatively to 511 ± 30 µm at 6 months after surgery in the cefuroxime group and from 607 ± 67 µm preoperatively to 519 ± 32 µm at 6 months in the NC group (p = .25). Endothelial cell loss was comparable between both groups: 33.4% versus 33.6% at 1 month (p = .97), 37.4% versus 34.9% at 3 months (p = .68) and 41.6% versus 38.3% at 6 months (p = .42) in the cefuroxime and NC groups, respectively. The rates of rebubbling, graft rejection, and cystoid macular edema were not significantly higher in the cefuroxime group.Conclusion: The use of intracameral cefuroxime during simple or combined DMEK did not lead to higher graft endothelial cell loss.

Post-surgical management of cataract: Light and dark in the 2020s

Cataract surgery is the most frequently performed elective surgery worldwide. Although considered a safe procedure, potentially sight-threatening adverse events are possible. Among these, post-surgical inflammation and infections are the most relevant. Anti-inflammatory drugs, such as corticosteroids, and topical antibiotics are the pillars for the treatment of inflammation and for the prevention of infections. However, uncertainties remain regarding the duration of both topical antibiotic prophylaxis and corticosteroid treatment. LEADER7, a recent international clinical study conducted with the new fixed combination of levofloxacin and dexamethasone eye drops in patients undergoing uncomplicated cataract surgery, found that 1-week topical antibiotic prophylaxis is just as effective as the 2-week course commonly used in clinical practice. The study also showed that treatment for 1 week with dexamethasone results in complete resolution of inflammatory signs and symptoms in over 85% of patients, for whom further prolongation of corticosteroid treatment is, therefore, not necessary. This new treatment strategy can represent a significant step forward to reduce the unjustified use of prophylactic antibiotics after cataract surgery, limiting the emergence of bacterial resistance, as well as representing an opportunity to optimize the use and safety of the corticosteroid treatment.

Acute macular edema and serous detachment on the first day after phacoemulsification surgery: A case report

Purpose

To report a case of an acute macular edema with serous retinal detachment on the first day after uncomplicated phacoemulsification surgery with the use of a standard dose of intracameral cefuroxime at the end of the surgery.

Observations

A 46-year-old man underwent a technically uneventful right eye phacoemulsification surgery using a standard dose (1mg/0.1mL) of cefuroxime solution injected into the anterior chamber at the end of the surgery. Serous macular edema and detachment were in our case observed on the first post-operative day. Without surgical intervention fast clinical recovery was observed and best corrected visual acuity improved to the final visual outcome of 1.0, which was satisfactory 10 days after surgery.

Conclusions and Importance

Acute serous macular detachment and edema should be considered in cases of poor visual acuity in the early postoperative period. The role of a standard dose of cefuroxime toxicity should be more widely explored and discussed.

Comparison of the local effects of different intracameral cefuroxime solutions on rabbit cornea

PURPOSE

We aimed to compare the local effects of intracameral cefuroxime diluted in normal saline (SF groups) against those of cefuroxime in balanced salt solution (BSS group) on the cornea of rabbits.

MATERIALS AND METHODS

Fourteen New Zealand albino rabbits were randomised into two groups. The right eyes of the rabbits in the SF group I were injected intracamerally with 1 mg cefuroxime diluted with 0.1 mL normal saline (n = 7), whereas the right eyes of the BSS group II were injected with 1 mg intracameral cefuroxime diluted with 0.1 mL with balance salt solution, and the left eyes of all rabbits received no treatment group III (control group). Corneal thickness was measured with pachymetry before and 1 week after the injection. Corneal samples were evaluated with light, specular and electron microscopy.

RESULTS

Mean endothelial cell count was lower in the SF than in the BSS and control groups. Although an increase in corneal thickness was found in both treatment groups, this was not the case for the control group. The corneal endothelium preserved its hexagonal structure in all groups. Although both treatment groups showed a loss of endothelial microvilli, this was more prevalent in the SF group. However, microvilli were preserved in the control group. Dissolution of tight junctions in corneal endothelium was observed in the SF group only. Mitochondrial swelling, coarsening of endoplasmic reticulum, cytoplasmic vacuolisation, and increased endothelial cell sizes were the same in both treatment groups but was not observed in the control group. Thicker and more oedematous corneal stroma were observed in the SF group compared with the BSS and control groups.

CONCLUSION

Dilution of intracameral cefuroxime in BSS yielded superior results compared with dilution in normal saline owing to toxicity to the endothelial cells and decline in the endothelial cell number, resulting in intracellular and intercellular morphological changes. BSS or any other solution with proven safety should be used in clinical studies.

Commonly used intracameral antibiotics for endophthalmitis prophylaxis: A literature review

Endophthalmitis is a serious complication of cataract surgery that occurs in thousands of patients each year. To decrease the incidence of postoperative endophthalmitis, many surgeons inject intracameral antibiotics (cefuroxime, moxifloxacin, and vancomycin) routinely at the end of surgery. A large number of recently published retrospective studies and large database analyses have reported decreased endophthalmitis rates with routine antibiotic use, and the only prospective, multicenter, randomized trial performed by the European Society of Cataract and Refractive Surgery demonstrated that intracameral cefuroxime decreases the incidence of postoperative endophthalmitis. Routine cefuroxime use has become common in many European countries, whereas moxifloxacin is the most commonly used drug in India, and vancomycin use predominates in Australia. The decision regarding whether or not to use intracameral prophylaxis and the drug that is selected varies considerably throughout the world because of antibiotic availability and cost, and the spectrum of causative organisms. Adverse events due to intracameral antibiotics are infrequent, but complications such as hemorrhagic occlusive retinal vasculitis have been reported. Because additional prospective, comparative trials have not been performed, a consensus regarding best practices to prevent postoperative endophthalmitis has not been reached. Additionally, many surgeons do not routinely use intracameral antibiotics because they believe them unnecessary with modern aseptic techniques, small incision surgery, and shorter operating times. We discuss the most commonly used intracameral antibiotics, present the risks and potential benefits of this approach, and highlight challenges with drug compounding and safety.

Endophthalmitis prophylaxis by intracameral antibiotics: In vitro model comparing vancomycin, cefuroxime, and moxifloxacin

PURPOSE

To compare the efficacy of intracameral vancomycin, cefuroxime, and moxifloxacin on postoperative bacterial endophthalmitis rates.

SETTING

Norwalk Hospital, Norwalk, Connecticut, USA.

DESIGN

Experimental study.

METHODS

Bacteria and intraocular lenses (IOLs) were incubated with vancomycin, cefuroxime, moxifloxacin, or combinations. Antibiotic concentrations were high, corresponding to clinical maximum intracameral doses (1.0 mg vancomycin or cefuroxime, 0.5 mg moxifloxacin), or low (one third of clinical maximum dose). The following bacteria were isolated from patients with endophthalmitis: 18 strains including 6 staphylococci, 6 streptococci, 3 pseudomonad, and 3 propionibacteria. Samples were diluted by half every 2 hours to model the half-life of intracameral antibiotics. At 24 hours, samples were vortexed to shake bacterial biofilms loose from the IOLs. The bacterial broth was plated and colonies were counted 24 hours later.

RESULTS

Efficacy against staphylococci was concentration dependent; all antibiotics were effective at high concentrations, while low concentrations were in general ineffective. Streptococci and propionibacteria were nearly eliminated by all antibiotics at low concentrations. Pseudomonads were most effectively treated by high-dose moxifloxacin and its combinations.

CONCLUSIONS

Broadest coverage against common pathogens should be obtained by high-dose moxifloxacin (0.5 mg intracameral). Submaximum dosing, which could occur if aqueous is released to lower intraocular pressure after injection, compromises the efficacy against staphylococci and pseudomonads. All antibiotics, even at low doses, were effective against streptococci and propionibacteria, suggesting that many of the worst endophthalmitis outcomes could be prevented by intracameral use of any of the 3 antibiotics used in this study.

[Complications of intracameral cefuroxime in cataract surgery]

Intracameral injection of cefuroxime during phacoemulsification is considered effective in preventing endophthalmitis. Its widespread usage has led to the accumulation of data on local and systemic adverse reactions. The analysis of complications of cataract surgery with cefuroxime injections described in literature has allowed identifying a few different clusters of toxic and allergic reactions to intracameral cefuroxime for the first time. These clusters included toxic anterior segment syndrome, serous retinal detachment with macular edema, retinal hemorrhagic infarction and anaphylactic reaction. The first two types develop in the cases of both correct and incorrect dosages, and both have favorable prognosis. Retinal hemorrhagic infarction was observed in cases with more than 50 mg intracameral antibiotic injected in the anterior chamber and was accompanied by persistent irreversible visual deterioration. Anaphylactic shock in response to a standard dose of intracameral cefuroxime was described in patients allergic to penicillin. Every clinical variant has specific complication mechanisms, prevention and treatment options. Antibiotic dilution done by medical staff accounts for the risk of incorrect dosage and related complications. Clinical manifestations of the complications of antibiotic prophylaxis should be considered when specifying the causes of decreased vision in the early postoperative period.

Application of Vancomycin Powder to Reduce Surgical Infection and Deep Surgical Infection in Spinal Surgery: A Meta-analysis

STUDY DESIGN

This was a meta-analysis study.

OBJECTIVE

Our meta-analysis study aimed to evaluate the efficacy of vancomycin powder to reduce the surgical site infection (SSI) in spinal surgery.

SUMMARY OF BACKGROUND DATA

The SSI is a potential and devastating complication after spinal surgery. Local application of vancomycin powder is an attractive adjunctive therapy to reduce SSI in spinal surgery.

METHODS

Studies were identified from PubMed, The Cochrane Library, AMED, Web of Science, Scopus, Ovid, EMBASE, and Ebsco Medline. The fixed-effects model was used to compute the merge of relative risk and 95% confidence interval (CI). Heterogeneity tests were checked by I statistics. Subgroup analysis was performed to determine whether vancomycin powder was beneficial, that could reduce the SSI in spinal surgery, or not. Publication bias was explored by funnel plot.

RESULTS

We included 21 studies for final analysis. In our analysis, application of vancomycin powder was associated with a significantly reduced risk of SSI and deep SSI. Pooled relative risks showed significant changes: SSI, 0.36 (95% CI: 0.27-0.47, P=0.000), SSI in the instrumented group, 0.35 (95% CI: 0.25-0.49, P=0.000), SSI in the noninstrumented group, 0.39 (95% CI: 0.24-0.65, P=0.000), deep SSI, 0.28 (95% CI: 0.18-0.44, P=0.000), and the incidence pseudoarthrosis, 0.88 (95% CI: 0.35-2.21, P=0.784). In the subgroup analysis, vancomycin powder showed beneficial effects to SSI in the instrumented group. Pooled the heterogeneity: SSI (P=0.124, I=30.0%), SSI in the instrumented group (P=0.366, I=8.2%), SSI in the noninstrumented group (P=0.039, I=60.5%), deep SSI (P=0.107, I=33.5%).

CONCLUSIONS

The application of vancomycin powder could decrease the SSI and deep SSI in spinal surgery. In the subgroup, vancomycin powder is beneficial to the SSI in the instrumented group. The available evidence is too limited to make the conclusion that the use of vancomycin powder causes pseudoarthrosis in spinal surgery, its extrapolation should be carefully executed.

Toxic anterior segment syndrome: A review

Toxic anterior segment syndrome is a surgical complication characterized by a noninfectious anterior chamber inflammatory reaction having multiple etiologies. The clinical signs (prominent limbus-to-limbus corneal edema, anterior chamber inflammation) and symptoms (decreased visual acuity, discomfort) generally occur within the first 12-48 hours after intraocular surgery. Most patients achieve good clinical and visual outcomes when there is a prompt clinical diagnosis and adequate treatment. We review the literature on toxic anterior segment syndrome, emphasizing its etiology, pathophysiology, and clinical and surgical management, as well as prognosis and sequelae. Our goal is to reduce the frequency of toxic anterior segment syndrome by highlighting the importance of prevention, early recognition, and distinguishing toxic anterior segment syndrome from infectious endophthalmitis.

Effect of Intracameral Ophthalmic Cefuroxime Solution (Aprokam®) in the Prophylaxis of Cataract Surgery in Patients with Keratoplasty

Background:

Development of endophthalmitis during cataract surgery is one of the most severe complications and it may also result in blindness and globe loss.

Aims:

To evaluate the effect of an ophthalmic cefuroxime solution (Aprokam^®) that is prophylactically used in phacoemulsification surgery performed due to cataract that eventually occurs in patients with or without penetrating keratoplasty.

Study Design:

Case-control study.

Methods:

In this retrospective study, patients who had undergone penetrating keratoplasty and for whom phacoemulsification surgery was performed due to cataract and an intracameral ophthalmic cefuroxime solution (Aprokam^®) was administered for prophylaxis were evaluated in comparison with patients with cataract without keratoplasty. The following parameters were evaluated: postoperative anterior chamber reaction, intraocular pressure, best corrected visual acuity, corneal endothelial cell density, and central corneal thickness alterations.

Results:

A total of 42 patients (18 males, 24 females) with keratoplasty and 42 patients (17 males, 25 females) without keratoplasty were included in this study. An increase in visual acuity was observed in all the patients after cataract surgery (p<0.001). The mean corneal endothelial cell densitys were determined to be 2437.20±148.5 cells/mm² preoperatively in the study group and 2807.1±152.4 cells/mm² preoperatively in the control group. The mean corneal endothelial cell densitys were determined to be 2103.85±196.5 cells/mm² after the first postoperative month (p<0.001) in the study group and 2755.92±182.7 cells/mm² in the control group (p=0.17). The mean central corneal thickness in the study group were 565.78±11.5 μm preoperatively and 584.65±12.7 μm after the first postoperative month (p<0.001). No difference was observed in the control group in terms of preoperative and postoperative central corneal thickness and endothelial cell density. There was no significant difference between the groups in terms of the intraocular pressure, anterior chamber reaction.

Conclusion:

There was no significant effect of the prophylactic intracameral use of ophthalmic cefuroxime solution (Aprokam^®) on the endothelial cells which was used in patients with keratoplasty for whom cataract surgery was performed.

Dose and administration of intracameral moxifloxacin for prophylaxis of postoperative endophthalmitis

PURPOSE

To review current and past practices of intracameral antibiotic administration for infection prophylaxis in cataract surgery; to review the benefits and liabilities of available prophylactic drugs, dosage determination, and administration protocols; and to devise an optimum dose and administration protocol for intracameral moxifloxacin.

SETTING

Humber River Hospital and the University of Toronto, Toronto, Ontario, Canada.

DESIGN

Retrospective evaluation of treatment modality.

METHODS

This study consisted of a detailed review of the history, drugs, and methods of intracameral prophylaxis and microbiological and pharmacodynamics analysis of options. A review of potential drug sources and doses was performed and 1 drug, dose, and administration protocol was selected. The current method's adoption reasons are described followed by the authors' experience.

RESULTS

A single infection in 3430 cases occurred with a moxifloxacin-resistant strain of Staphylococcus epidermidis when moxifloxacin 100 mcg in 0.1 mL was used. Increasing the dose and changing the administration technique resulted in no infections in 4601 cases and no detrimental side effects or complications.

CONCLUSION

Intracameral moxifloxacin prepared by dilution of 3 cc moxifloxacin 0.5% (Vigamox) with 7 cc balanced salt solution and with the administration of 0.3 to 0.4 cc (450 to 600 mcg.) as the final step in cataract surgery via the side port after the main incision has been sealed and hydrated showed advantages over alternative intracameral antibiotic prophylactic methods, with minimum risk.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Comparative analysis of the safety and efficacy of intracameral cefuroxime, moxifloxacin and vancomycin at the end of cataract surgery: a meta-analysis

BACKGROUND

Current practice methods are unclear as to the most safe and effective prophylactic pharmacotherapy and method of delivery to reduce postoperative endophthalmitis occurrence.

METHODS

A systematic review and meta-analysis using Meta-analysis of Observational Studies in Epidemiology guidelines was performed to compare the efficacy of intracameral cefuroxime, moxifloxacin and vancomycin in preventing postphacoemulsification cataract surgery endophthalmitis. A safety analysis of intracameral antibiotics was concurrently performed.

DATA SOURCES

BIOSIS Previews, CINAHL, ClinicalTrials.gov, Cochrane Library, Dissertations & Theses, EMBASE, PubMed, ScienceDirect and Scopus were searched from inception to January 2017. Data were pooled using a random effects model. All articles were individually reviewed and data were extracted by two independent reviewers. Funnel plot, risk of bias and quality of evidence analyses were performed.

RESULTS

Seventeen studies with over 900 000 eyes were included, which favoured the use of intracameral antibiotics at the end of cataract surgery (OR 0.20; 95% CI 0.13 to 0.32; P<0.00001). The average weighted postoperative endophthalmitis incidence rates with intracameral cefuroxime, moxifloxacin and vancomycin were 0.0332%, 0.0153% and 0.0106%, respectively. Secondary analyses showed no difference in efficacy between intracameral plus topical antibiotics versus intracameral alone (P>0.3). Most studies had low to moderate risk of bias. The safety analysis showed minimal toxicity for moxifloxacin. Dosing errors led to the majority of toxicities with cefuroxime. Although rare, vancomycin was associated with toxic retinal events.

CONCLUSION

Intracameral cefuroxime and moxifloxacin reduced endophthalmitis rates compared with controls with minimal or no toxicity events at standard doses. Additionally, intracameral antibiotics alone may be as effective as intracameral plus topical antibiotics.

Differences in energy and corneal endothelium between femtosecond laser-assisted and conventional cataract surgeries: prospective, intraindividual, randomized controlled trial

AIM

To compare intraoperative phacoemulsification parameters and its effect on the corneal endothelium of eyes undergoing femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification (CP) cataract surgery.

METHODS

Two hundred eyes from one hundred patients were included in a prospective, non-blinded, randomized, controlled, intraindividual clinical study. One hundred eyes underwent FLACS while their one hundred fellow eyes underwent CP. All surgeries were performed using the Victus^® femtosecond laser platform and Infinity^® Vision System phacoemulsification machine. Primary outcome measure was endothelial cell density 6mo after surgery. Secondary outcome measures included central corneal thickness (CCT), average cell area, standard deviation, coefficient of variation and hexagonality before surgery and 6mo after surgery and endothelial cell density loss during this period were also evaluated. Intraoperative efficiency parameters [cumulative dissipated energy (CDE), total intraocular surgery time, total ultrasound time, total phacoemulsification time, total torsional energy time, total aspiration time, ultrasound energy, torsional amplitude and fluid required during surgery] were also collated.

RESULTS

Data from these patients was not considered for analysis. Data from 92 patients were analysed. Postoperative endothelial cell density (cells/mm²) between groups (2211.88±392.49 CP; 2246.31±403.48 FLACS) was not statistically significant (P=0.869). Total ultrasound time, torsional energy time, CDE and fluid requirements were significantly lower the FLACS group (P<0.05). Other parameters did not show statistically significant difference between FLACS and CP.

CONCLUSION

FLACS displays significant improvements in phacoemulsification parameters in comparison to CP. There are no significant differences in corneal endothelium measures between FLACS and CP.

The Effect of Intraoperative Antibiotics in Irrigating Solutions on Aqueous Humor Contamination and Endophthalmitis after Phacoemulsification Surgery

PURPOSE

To determine the efficacy of intraoperative antibiotic use in irrigating solutions on aqueous humor contamination during phacoemulsification surgery and to evaluate the corresponding risk of postoperative endophthalmitis.

METHODS

644 eyes of 640 patients who underwent phacoemulsification surgery with foldable intraocular lens (IOL) implantation were included in this study. Preoperative conjunctival smears were taken and eyes were allocated to receive irrigating infusion fluid containing either balanced salt solution (BSS)-only (group 1; 322 eyes) or BSS with antibiotics (vancomycin and gentamycin) during surgery (group 2; 322 eyes). Bacterial contamination rates of aqueous humor samples taken in the beginning and at the end of operation were compared. Predictive factors for the development of postoperative endophthalmitis were determined by clinical and microbiologic analyses.

RESULTS

The rates of culture-positivity were similar between group 1 and group 2 for both preoperative conjunctival smears and aqueous samples (p > 0.05). Aqueous samples taken at the end of operation were found to be contaminated in 68 (21.1%) eyes in group 1 and 22 (6.8%) eyes in group 2, and the difference was significant (p = 0.0001; OR = 3.65 (2.1-6.0)). Capsular rupture was associated with higher rate of contamination in both groups (p = 0.0001; OR = 7.7 and p = 0.0001; OR = 8.1). Two eyes in the BSS-only group developed postoperative endophthalmitis and these cases had posterior capsular rupture during the surgery and culture-positivity for staphylococcus epidermidis throughout the study.

CONCLUSIONS

Intraoperative antibiotic irrigation decreases aqueous humor contamination during phacoemulsification. Further studies are warranted to determine the interrelationship between aqueous humor contamination and endophthalmitis in eyes with posterior capsular rupture.

Antibiotic prophylaxis in cataract surgery - An evidence-based approach

Various protocols are being followed for endophthalmitis prophylaxis in cataract surgery, and this subject continues to be a matter of debate. We summarize the most recent evidence-based studies on this topic with additional stress on intracameral (IC) antibiotic prophylaxis. Here, we discuss several large, international clinical studies which discuss the efficacy, adoption, safety, cost, and newer trends in antibiotic prophylaxis. Majority of these studies report a significant reduction in endophthalmitis rates with IC antibiotic prophylaxis. Efficacy data have been reported for IC cefuroxime, vancomycin, and moxifloxacin. Surgeons are now looking for alternatives to vancomycin for IC prophylaxis because of its association with the rare but sight-threatening complication of hemorrhagic occlusive retinal vasculitis. A recent large clinical study shows convincing efficacy with IC moxifloxacin prophylaxis. Two large studies have also reported significant endophthalmitis reduction following use of IC antibiotic prophylaxis, in eyes with posterior capsule tear which are at highest risk for infection. Except for one randomized controlled trial, there is a lack of prospective data on this subject; however, considering the complexity of performing such studies, surgeons have to rely on the mounting evidence from other recent big data studies. Availability of approved intraocular antibiotic formulations will see a much higher adoption in the future.

Effects of intracameral cefuroxime on corneal endothelial cell counts and its morphology after cataract surgery

Background

Endophthalmitis is one of the most important complications after cataract surgery and in case event can cause many symptoms, such as severe decrease in eyesight and/or even the loss of vision. Employing methods to reduce this problem is very important. The aim of this study was to evaluate the effect of intracameral cefuroxime after cataract surgery on corneal endothelial cell counts and its morphology.

Methods

In this study, 32 eyes of 30 patients underwent endothelial cell count and morphology assessment by ConfoScan III device before and 1 month after cataract surgery. All patients undertaken cataract surgery by one surgeon and by one method. Intracameral cefuroxime (1 mg/0.1 ml) was used as prophylaxis of postoperative endophthalmitis at the end of operation.

Results

In this study, the rate of corneal endothelial cell loss 1 month after cataract surgery was 8.4%, and the rate of endothelial cells polymegathism before and after cataract surgery did not differ statistically. During the follow-up period, there were no cases of endophthalmitis or other complications.

Conclusion

With regard to the importance of the intracameral cefuroxime in a reduction in the rate of endophthalmitis after cataract surgery and that harmful effects on the endothelial cells were not seen, this method can be considered as a suitable method for endophthalmitis prophylaxis.

Endophthalmitis Prophylaxis for Cataract Surgery

Endophthalmitis after cataract surgery is a rare but potentially devastating complication. There is great variability in endophthalmitis prophylaxis practice patterns worldwide. Treatment varies globally and is based on the microbiological profile and availability of formulations. Periocular povidone-iodine antisepsis is universally adopted and considered the standard of care in most practices. Perioperative topical antibiotics are also very popular despite the lack of level 1 evidence confirming efficacy. Based on growing observational evidence, routine intracameral antibiotic prophylaxis is increasing, especially where approved commercial intraocular preparations are available. This review updates recent trends and evidence regarding endophthalmitis prophylaxis and the preferred choice of intracameral antibiotics.

Antibiotic prophylaxis in cataract surgery in the setting of penicillin allergy: A decision-making algorithm

Cataract surgery is the most commonly performed surgical procedure in many developed countries. Postoperative endophthalmitis is a rare complication with potentially devastating visual outcomes. Currently, there is no global consensus regarding antibiotic prophylaxis in cataract surgery despite growing evidence of the benefits of prophylactic intracameral cefuroxime at the conclusion of surgery. The decision about which antibiotic regimen to use is further complicated in patients reporting penicillin allergy. Historic statistics suggesting crossreactivity of penicillins and cephalosporins have persisted into modern surgery. It is important for ophthalmologists to consider all available antibiotic options and have an up-to-date knowledge of antibiotic crossreactivity when faced with the dilemma of choosing appropriate antibiotic prophylaxis for patients undergoing cataract surgery with a history of penicillin allergy. Each option carries risks, and the choice may have medicolegal implications in the event of an adverse outcome. We assess the options for antibiotic prophylaxis in cataract surgery in the setting of penicillin allergy and provide an algorithm to assist decision-making for individual patients.

Safety Profile of Stromal Hydration of Clear Corneal Incisions with Cefuroxime in the Mouse Model

PURPOSE

The use of sutureless clear corneal incisions (CCIs) for phacoemulsification is an established surgical technique, but the dynamic morphology of the wound and poor construction can lead to an increased risk of postoperative endophthalmitis. Stromal hydration with balanced salt solution (BSS) can improve the self-sealing status. Intracameral cefuroxime has reduced endophthalmitis rates. This study investigates the safety profile of stromal hydration with cefuroxime, as sequestering antibiotic at the wound may potentially provide added protection against infection.

METHODS

MF-1 mice underwent bilateral CCI, followed by stromal hydration with 5 μL of 10 mg/mL cefuroxime, cefuroxime-texas red conjugate (for detection using confocal microscopy), or BSS. Corneas were harvested from 1 h to 12 weeks postoperatively; gross morphology, histology, and apoptotic cell death levels were investigated to determine the safety profile. Bactericidal activity of cefuroxime was assayed using homogenized whole cornea following stromal hydration at 1 h, 24 h, and day 7 against gram-negative Escherichia coli.

RESULTS

Cefuroxime stromal hydration did not alter corneal morphology, with no evidence of corneal scarring or vascularization. Corneal histology and levels of apoptosis were minimal and comparable to the BSS groups up to 12 weeks. Confocal microscopy detected cefuroxime-texas red up to 1 week surrounding the corneal wound. Whole corneal tissue homogenates displayed bactericidal activity up to 24 h postoperatively.

CONCLUSIONS

Stromal hydration of CCI with cefuroxime is safe in mouse corneas. A reservoir of antibiotic at the wound can potentially act as a barrier of defense against infection following cataract and associated ocular surgery.

Transient macular edema after intracameral injection of a moderately elevated dose of cefuroxime during phacoemulsification surgery

IMPORTANCE

Intracameral injection of cefuroxime sodium (1 mg/0.1 mL) has been reported to reduce the risk of endophthalmitis following cataract surgery. In the United States it must be compounded, which is subject to dilution error. We describe a series of 13 eyes that received intracameral injection of cefuroxime sodium, 9 mg/0.1 mL, intraoperatively.

OBSERVATIONS

On postoperative day 1, 6 of 13 eyes (46%; 95% CI, 19%-75%) had visual acuity of 20/70 or worse and macular edema. Spectral-domain optical coherence tomography of 2 eyes revealed central subfield thicknesses of 909 and 873 µm. On postoperative day 4, the mean (SD) central subfield thickness was 309 (78) µm in the 6 eyes with diagnosed macular edema, 279 (23) µm in the fellow eyes, and 271 (38) µm in the 7 exposed eyes without macular edema. The mean (SD) time to resolution of macular edema was 5.2 (1.3) days; the final central subfield thickness ranged from 193 to 293 µm. All eyes, except 2 with preexisting ocular comorbidity, had a best-corrected final visual acuity at 1 month of 20/30 or better. Significant corneal edema was not observed.

CONCLUSIONS AND RELEVANCE

Intracameral injection of cefuroxime sodium at a dose of 9 mg/0.1 mL was associated with transient macular edema and diminished visual acuity in 6 of 13 exposed eyes (46%), resolving largely within 1 week.

Comparative Effectiveness of Antibiotic Prophylaxis in Cataract Surgery

PURPOSE

Intracameral injection is an effective method for preventing infection, but no controlled study has been published in the United States.

DESIGN

We conducted an observational, longitudinal cohort study to examine the effect of topical and injected antibiotics on risk of endophthalmitis.

PARTICIPANTS

We identified 315 246 eligible cataract procedures in 204 515 members of Kaiser Permanente, California, 2005-2012.

METHODS

The study used information from the membership, medical, pharmacy, and surgical records from the electronic health record.

MAIN OUTCOME MEASURES

The adjusted odds ratio (OR) and 95% confidence interval (CI) for the association of antibiotic prophylaxis (route and agent) with risk of endophthalmitis was estimated using logistic regression analysis.

RESULTS

We confirmed 215 cases of endophthalmitis (0.07% or 0.7/1000). Posterior capsular rupture was associated with a 3.68-fold increased risk of endophthalmitis (CI, 1.89-7.20). Intracameral antibiotic was more effective than topical agent alone (OR, 0.58; CI, 0.38-0.91). Combining topical gatifloxacin or ofloxacin with intracameral agent was not more effective than using an intracameral agent alone (compared with intracameral only: intracameral plus topical, OR, 1.63; CI, 0.48-5.47). Compared with topical gatifloxacin, prophylaxis using topical aminoglycoside was ineffective (OR, 1.97; CI, 1.17-3.31).

CONCLUSIONS

Surgical complication remains a key risk factor for endophthalmitis. Intracameral antibiotic was more effective for preventing post-cataract extraction endophthalmitis than topical antibiotic alone. Topical antibiotic was not shown to add to the effectiveness of an intracameral regimen.