***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE To determine whether repeated exposure of ocular and nasopharyngeal flora to ophthalmic antibiotics promotes antimicrobial resistance in patients undergoing intravitreal injections for choroidal neovascularization ( CNV ) . DESIGN Prospect i ve , r and omized , controlled , clinical trial . PARTICIPANTS Forty-eight eyes of 24 patients undergoing unilateral intravitreal injections for CNV . METHODS Patients were assigned r and omly to 1 of 4 ophthalmic antibiotics ( azithromycin 1 % , ofloxacin 0.3 % , gatifloxacin 0.3 % , moxifloxacin 0.5 % ) to be used after each injection in the treatment eye only . Bilateral conjunctival and unilateral nasopharyngeal cultures on the treatment side were obtained at baseline and were repeated at each subsequent visit for 1 year . All bacterial isolates were tested for antibiotic susceptibility to 16 different antibiotics using the Kirby-Bauer disc diffusion technique . Genetic analysis of bacteria strains was performed using pulse-field gel electrophoresis . MAIN OUTCOME MEASURES Changes in antibiotic susceptibility patterns of conjunctival and nasopharyngeal flora over time and emergence of resistant strains . RESULTS Eight subjects ( 33 % ) grew Staphylococcus aureus from the nasopharynx and 1 subject ( 13 % ) showed emergence of a resistant strain . Coagulase-negative staphylococci ( CNS ) cultured from eyes repeatedly exposed to fluoroquinolone antibiotics demonstrated significantly increased rates of resistance to third- and fourth-generation fluoroquinolones compared with untreated eyes . Resistance to ofloxacin and levofloxacin was roughly 85 % ( P = 0.003 ) , and resistance to gatifloxacin and moxifloxacin approached 67 % ( P = 0.009 ) and 77 % ( P<0.001 ) , respectively . In contrast , CNS isolated from eyes repeatedly exposed to azithromycin demonstrated significantly increased resistance ( 94 % ) to erythromycin and azithromycin when compared with control eyes ( P = 0.009 ) and decreased resistance to third-generation ( P<0.03 ) and fourth-generation ( P<0.001 ) fluoroquinolones when compared with eyes exposed to fluoroquinolones . CONCLUSIONS Repeated exposure of ocular and nasopharyngeal flora to ophthalmic antibiotics selects for resistant strains OBJECTIVE To describe the incidence and outcomes of endophthalmitis after intravitreal injections of anti-vascular endothelial growth factor agents in the Comparison of Age-Related Macular Degeneration Treatments Trials ( CATT ) and to assess the effect of prophylactic topical antimicrobials on incidence . DESIGN Cohort study within a r and omized clinical trial . PARTICIPANTS Patients enrolled in CATT . METHODS Patients with neovascular age-related macular degeneration received intravitreal injections of ranibizumab or bevacizumab under 1 of 3 dosing regimens . The study protocol specified preinjection preparation to include use of a sterile lid speculum and povidone iodine ( 5 % ) . Use of preinjection and postinjection antibiotics was at the discretion of the treating ophthalmologist . Patients were followed up monthly for 2 years . MAIN OUTCOME MEASURES Development of endophthalmitis and visual acuity . RESULTS Endophthalmitis developed after 11 of 18 509 injections ( 1 per 1700 [ 0.06 % ] ; 95 % confidence interval , 0.03%-0.11 % ) , and in 11 of 1185 patients ( 0.93 % ; 95 % confidence interval , 0.52 - 1.66 ) . Incidence of endophthalmitis was 0.15 % among injections with no antibiotic use , 0.08 % among injections with preinjection antibiotics only , 0.06 % among injections with postinjection antibiotics only , and 0.04 % among injections with preinjection and postinjection antibiotics ( P = 0.20 ) . All eyes were treated with intravitreal antibiotics and 4 underwent vitrectomy . Among the 11 affected eyes , the final study visual acuity was 20/40 or better in 4 eyes ( 36 % ) , 20/50 to 20/80 in 2 eyes ( 18 % ) , 20/100 to 20/160 in 3 eyes ( 27 % ) , and worse than 20/800 in 2 eyes ( 18 % ) . The final visual acuity was within 2 lines of the visual acuity before endophthalmitis in 5 eyes ( 45 % ) . CONCLUSIONS Rates of endophthalmitis were low and similar to those in other large-scale studies . Use of topical antibiotics either before or after injection does not seem to reduce the risk for endophthalmitis PURPOSE We sought to assess the efficacy of 3-day topical gatifloxacin use in combination with povidone-iodine ( PVI ) versus PVI alone in eliminating conjunctival bacterial flora in patients scheduled to undergo intravitreal ( IVT ) injection . DESIGN Prospect i ve , r and omized single-blind clinical trial . PARTICIPANTS We included 129 patients scheduled to undergo 273 IVT injections at California Vitreoretinal Center at Stanford University . METHODS Study patients were r and omized to self-administration of gatifloxacin drops for 3 days before injection , or no pretreatment antibiotics . Cultures were collected from the bulbar conjunctiva at the injection site and at the corresponding location in the fellow eye before PVI preparation . After topical PVI treatment and immediately before injection , a third culture was obtained at the injection site . Additionally , the injection needle was also cultured after the procedure . MAIN OUTCOME MEASURES Incidence of positive bacterial sample s collected from injection site conjunctiva and injection needles . RESULTS Three-day gatifloxacin use result ed in a significantly lower rate of SeptiChek ( Becton Dickinson , Franklin Lakes , NJ ) positive cultures compared with untreated controls ( 21 % vs 48 % respectively , P = 0.005 ) . After topical PVI , the rate of positive bacterial cultures in gatifloxacin-treated and control eyes were similar ( 8 % and 4 % , respectively ; P = 0.324 ) . CONCLUSIONS Although 3-day topical gatifloxacin use is effective in reducing the frequency of conjunctival bacterial growth relative to untreated eyes , antibiotic use confers no additional benefit in combination with PVI than eyes receiving PVI alone . This supports that topical PVI is an effective preinjection monotherapy for infection prophylaxis in the setting of IVT injections Objectives Appropriate reporting is central to the application of findings from research to clinical practice . The Strengthening the Reporting of Observational Studies in Epidemiology ( STROBE ) recommendations consist of a checklist of 22 items that provide guidance on the reporting of cohort , case – control and cross-sectional studies , in order to facilitate critical appraisal and interpretation of results . STROBE was published in October 2007 in several journals including The Lancet , BMJ , Annals of Internal Medicine and PLoS Medicine . Within the framework of the revision of the STROBE recommendations , the authors examined the context and circumstances in which the STROBE statement was used in the past . Design The authors search ed the Web of Science data base in August 2010 for articles which cited STROBE and examined a r and om sample of 100 articles using a st and ardised , piloted data extraction form . The use of STROBE in observational studies and systematic review s ( including meta-analyses ) was classified as appropriate or inappropriate . The use of STROBE to guide the reporting of observational studies was considered appropriate . Inappropriate uses included the use of STROBE as a tool to assess the method ological quality of studies or as a guideline on how to design and conduct studies . Results The authors identified 640 articles that cited STROBE . In the r and om sample of 100 articles , about half were observational studies ( 32 % ) or systematic review s ( 19 % ) . Comments , editorials and letters accounted for 15 % , method ological articles for 8 % , and recommendations and narrative review s for 26 % of articles . Of the 32 observational studies , 26 ( 81 % ) made appropriate use of STROBE , and three uses ( 10 % ) were considered inappropriate . Among 19 systematic review s , 10 ( 53 % ) used STROBE inappropriately as a tool to assess study quality . Conclusions The STROBE reporting recommendations are frequently used inappropriately in systematic review s and meta-analyses as an instrument to assess the method ological quality of observational studies PURPOSE To determine the baseline antibiotic susceptibility patterns of conjunctival and nasopharyngeal flora isolated from patients undergoing intravitreal ( IVT ) injections for choroidal neovascularization ( CNV ) . DESIGN Prospect i ve , observational study . PARTICIPANTS Forty-eight eyes of 24 patients undergoing unilateral IVT injections for CNV . METHODS Bilateral conjunctival and unilateral nasopharyngeal cultures on the treatment side were taken before application of any topical medications . MAIN OUTCOME MEASURES Bacterial isolates were identified and tested for antibiotic susceptibility to 16 different antibiotics using the Kirby-Bauer disc diffusion technique . RESULTS A total of 57 bacterial isolates were obtained from the conjunctiva of 48 eyes . Coagulase-negative staphylococci ( CNS ) accounted for 37 of the 57 isolates ( 65 % ) . The most common CNS organisms were Staphylococcus epidermidis and Staphylococcus lugdunensis accounting for 73 % and 11 % of CNS isolates , respectively . More than half of S. epidermidis isolates demonstrated some level of resistance to ofloxacin and levofloxacin , and 33 % and 37 % of isolates showed some level of resistance against gatifloxacin and moxifloxacin , respectively . Some 60 % and 30 % of CNS isolates were resistant to ≥ 3 and ≥ 5 antibiotics , respectively . Among the 24 nasopharyngeal cultures , 8 ( 33 % ) grew Staphylococcus aureus , and 1 of the 8 isolates ( 13 % ) was resistant to all penicillin , cephalosporin , macrolide , and fluoroquinolone antibiotics tested . CONCLUSIONS Our results demonstrate subtantial levels of resistance to third- and fourth-generation fluoroquinolones and multiresistance among ocular CNS isolated from patients undergoing IVT injections for CNV t r 5 d r h a i i NTRAVITREAL INJECTIONS HAVE RAPIDLY BECOME ONE of the most common medical procedures in the United States , with 1 270 836 intravitreal injections performed for Part B Medicare recipients in 2009 ( Ross Brechner , personal communication , 2011 ) . Associated endophthalmitis is a rare complication with potentially devastating consequences and a well-documented incidence , occurring after approximately 1 out of 1000 to 5000 injections . Toward the goal of endophthalmitis prevention , certain methods in patient preparation have become common practice and guidelines have been published . Most recently , streptococcal species have been reported to cause a significant proportion of postinjection endophthalmitis ( 15%–42 % ) , suggesting the possibility of injection site contamination by aerosolized nasopharyngeal moisture droplets , leading authors to recommend wearing surgical masks or minimizing talking while preparing and administering intravitreal injections . While many of these recommendations have not been evaluated in prospect i ve r and omized trials , much can be gleaned from analysis of existing literature . Two major points of interest are the use of antisepsis  and antibiotics IMPORTANCE Treatment with intravitreal ( IVT ) injections has increased during the last several years as evidence has accumulated demonstrating the efficacy of anti-vascular endothelial growth factor agents in the treatment of neovascular age-related macular degeneration ( AMD ) and various retinal vascular diseases . Although IVT injections are generally safe , infectious endophthalmitis is a rare but devastating complication , and the risk of morbidity and vision loss from endophthalmitis is high . OBJECTIVE To examine the change in antibiotic resistance of ocular surface flora with repeated prophylactic use of antibiotics after IVT injection for AMD . DESIGN AND SETTING Prospect i ve , nonr and omized cohort study in 2 tertiary academic hospitals . PARTICIPANTS Patients 65 years and older with newly diagnosed AMD were recruited by 7 retinal specialists from July 1 , 2010 , through December 31 , 2011 . INTERVENTION The study group received topical moxifloxacin hydrochloride for 3 days after each monthly IVT injection . MAIN OUTCOME MEASURE Resistance to moxiflo 
    Output:
    
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 .