0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address 54.242.8.162. Please contact the publisher to request reinstatement.
Laboratory Sciences |

Intravitreal Dexamethasone Effect on Intravitreal Vancomycin Elimination in Endophthalmitis FREE

Susanna S. Park, MD, PhD; Robert V. Vallar, MD; Chian Huey Hong, MD; Sylviane von Gunten, MD; Kate Ruoff, PhD; Donald J. D'Amico, MD
[+] Author Affiliations

From the Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas (Drs Park, Vallar, and Hong); and the Retina Service, Massachusetts Eye and Ear Infirmary (Drs von Gunten and D'Amico), and the Clinical Microbiology Laboratory, Massachusetts General Hospital (Dr Ruoff), Boston. Dr Park is now with the Retina Department, The Permanente Medical Group Inc, Sacramento, Calif. Dr von Gunten is now with the Department of Ophthalmology, Geneva University Hospital, Geneva, Switzerland.


Arch Ophthalmol. 1999;117(8):1058-1062. doi:10.1001/archopht.117.8.1058.
Text Size: A A A
Published online

Objective  To determine whether intravitreal dexamethasone administration can alter the elimination of intravitreal vancomycin hydrochloride in rabbit eyes with experimental Streptococcus pneumoniae endophthalmitis.

Methods  Albino rabbits were infected with an intravitreal inoculum of S pneumoniae (2×103colony-forming units) and randomized after 24 hours to treatment with intravitreal vancomycin hydrochloride (1 mg), alone or in combination with intravitreal dexamethasone (400 µg). For comparison, uninfected eyes were similarly treated. All eyes were enucleated 24, 48, or 72 hours after treatment, and vitreous levels of vancomycin were quantitated using a fluorescence polarizing immunoassay.

Results  The half-life of intravitreal vancomycin in infected eyes was prolonged from 48 to 84 hours when eyes were treated with dexamethasone. Conversely, such treatment shortened the half-life in uninfected eyes from 56 to 42 hours.

Conclusions  Intravitreal dexamethasone administration reduces the elimination of intravitreal vancomycin in rabbit eyes with pneumococcal endophthalmitis, whereas an opposite effect is noted in uninfected eyes.

Clinical Relevance  In patients with eyes having endophthalmitis caused by virulent organisms, the elimination of intravitreal vancomycin may be reduced when intraocular inflammation is minimized with corticosteroid therapy. This may enhance the efficacy of intravitreal vancomycin therapy in treating the infection.

Figures in this Article

STREPTOCOCCUS pneumoniae is a frequently encountered microorganism in endophthalmitis associated with a filtration bleb.1,2 Eyes with pneumococcal endophthalmitis generally have a poor outcome, despite prompt initiation of antimicrobial drug therapy, because of the destructive inflammatory response induced by the infection. In a previous study,3 we used a rabbit model of pneumococcal endophthalmitis to show that intravitreal dexamethasone therapy, when used in conjunction with intravitreal vancomycin administration, markedly reduced the inflammation and tissue destruction associated with the infection. A more recent study4 using a contrast-enhanced magnetic resonance imaging technique showed that intravitreal dexamethasone use also markedly reduced the associated blood-ocular barrier breakdown. Because the degree of breakdown correlates with the degree of intraocular accumulation of proteins and leukocytes from the blood,57 it is possible that a change in breakdown may affect the rate of elimination of a drug from the eye after intraocular administration. In this study, intravitreal vancomycin levels were measured in healthy eyes and in eyes with pneumococcal endophthalmitis to determine whether intravitreal dexamethasone therapy affects the elimination of vancomycin from the vitreous after intravitreal administration.

CULTURE OF BACTERIA

A strain of S pneumoniae, isolated from a patient's corneal culture and used in a previous study3 of experimental pneumococcal endophthalmitis, was grown on Brucella agar containing 5% horse blood (BBL; Becton Dickinson Microbiology Systems, Cockeysville, Md) at 35°C as previously described. The cultured microorganisms were diluted in sterile saline solution to achieve a concentration of 2×104colony-forming units (CFU)/mL. The suspension of bacteria was freshly made just before animal inoculation. A viable bacterial count of the suspension was confirmed by the growth on horse blood agar plates.

ANIMAL STUDY

All animals were maintained and cared for in accordance with the Association for Research in Vision and Ophthalmology Resolution on the Use of Animals in Research. All animal experiments were conducted at the University of Texas Southwestern Medical Center, Dallas, in accordance with the study protocol approved by the institutional animal care and research advisory board. New Zealand albino rabbits weighing 2.0 to 2.5 kg were infected with an intravitreal inoculum of S pneumoniae (2000 CFU) as previously described (n=7 per data point per group, N=42 rabbits).3 Briefly, the rabbits were anesthetized with a 1-mL intramuscular dose of a solution containing an equal mixture of ketamine hydrochloride (100 mg/mL; Parke-Davis Pharmaceutical Research, Morris Plains, NJ) and xylazine hydrochloride (20 mg/mL; Mobay Corp, Shawnee, Kan). Topical anesthesia was achieved with 0.5% proparacaine hydrochloride ophthalmic solution (Allergan Inc, Irvine, Calif). When adequate anesthesia was achieved, anterior chamber paracentesis was performed in the right eye with a 30-gauge needle to yield about 0.1 mL of aqueous fluid. The right eye was infected with a direct intravitreal inoculum of live bacteria—a 0.1-mL suspension containing 2000 CFU—delivered through the pars plana into the vitreous using a 30-gauge needle. Infected eyes were examined by indirect ophthalmoscopy 24 hours after inoculation to confirm the presence of clinical signs of endophthalmitis, ie, moderate to severe conjunctival injection with vitreous haze resulting in at least partial obscuration of the retinal and choroidal vasculature. The eyes were randomized to treatment with intravitreal vancomycin hydrochloride (1 mg in 0.1 mL of solution), alone or in combination with intravitreal dexamethasone (400 µg in 0.1 mL of solution). For comparison, uninfected rabbit eyes were similarly randomized to treatment (n=7 per data point per group).

The rabbits were euthanized 24, 48, or 72 hours after treatment using an intracardiac dose of pentobarbital sodium (120 mg/kg). The treated eyes were enucleated and promptly frozen in liquid nitrogen. The frozen eyes were dissected and the vitreous was obtained after removing the cornea, iris, lens, and retina-choroid-sclera layer. The vitreous concentration of vancomycin was measured using a fluorescence polarization immunoassay as previously described (TDX; Abbott Laboratories, North Chicago, Ill).810 The vitreous concentration of protein was measured with a commercially available protein assay that uses bovine serum albumin as a standard (BCA protein assay; Pierce Chemical Co, Rockford, Ill).11

PHARMACOKINETIC AND STATISTICAL ANALYSIS

Pharmacokinetic analysis of the relationship between intravitreal vancomycin concentration and time was performed using a nonlinear least squares regression analysis as previously described.12 The vitreous concentration of vancomycin at time zero, estimated vitreous volume, and vitreous half-life of vancomycin were calculated based on observed intravitreal vancomycin concentrations. Based on the model selection criteria and coefficients of determination, the concentrations of intravitreal vancomycin over time were best fitted to a 1-compartment model, consistent with a previous report.12

Statistical analysis was performed for comparison of means using an unpaired, 2-tailed t test. Statistical significance was defined as P≤.05.

Clinical signs of endophthalmitis were present after 24 hours in all rabbit eyes infected with S pneumoniae. Intravitreal vancomycin concentration 72 hours after treatment was significantly higher in eyes treated with intravitreal dexamethasone and vancomycin compared with those treated with vancomycin alone (P=.03) (Figure 1 and Table 1). Conversely, the intravitreal protein concentration, a marker of inflammation and breakdown of the blood-ocular barrier, was significantly lower in eyes treated with intravitreal vancomycin and dexamethasone compared with those treated with vancomycin alone at 72 hours following treatment (P<.001) (Figure 2). Pharmacokinetic analysis revealed that intravitreal vancomycin elimination was decreased in infected eyes treated with dexamethasone (Table 2); dexamethasone prolonged the vitreous half-life of vancomycin in infected eyes from 48 to 84 hours.

Place holder to copy figure label and caption
Figure 1.

Intravitreal vancomycin levels 24 to 72 hours after vancomycin hydrochloride injection (1 mg) (n=7 per data point; values presented as mean±SEM). A, Infected eye treated with vancomycin (1 mg) alone. B, Infected eye treated with vancomycin (1 mg) and dexamethasone (400 µg). C, Uninfected eye treated with vancomycin (1 mg) alone. D, Uninfected eye treated with vancomycin (1 mg) and dexamethasone (400 µg).

Graphic Jump Location
Table Graphic Jump LocationTable 1. Vitreous Vancomycin Concentration After Intravitreal Injection in Rabbit Eyes With Pneumococcal Endophthalmitis
Place holder to copy figure label and caption
Figure 2.

Intravitreal protein concentrations in eyes with pneumococcal endophthalmitis after treatment with vancomycin hydrochloride, alone or combined with dexamethasone (n=7 per data point; values presented as mean±SEM). Asterisk indicates a statistically significant difference from eyes not treated with intravitreal corticosteroid drugs, based on an unpaired t test (P≤.05).

Graphic Jump Location
Table Graphic Jump LocationTable 2. Pharmacokinetic Variables of Intravitreal Vancomycin in Rabbits*

Intravitreal vancomycin concentration 72 hours after injection was significantly lower in uninfected rabbit eyes injected with intravitreal dexamethasone and vancomycin compared with those injected with vancomycin alone (P<.001) (Table 3 and Figure 1). However, intravitreal protein concentration did not significantly differ (P>.05) between the groups of uninfected eyes at all time points after intravitreal injection (Figure 3). On pharmacokinetic analysis, the presence of dexamethasone shortened the vitreous half-life of vancomycin in uninfected eyes from 56 to 42 hours (Table 2).

Table Graphic Jump LocationTable 3. Vitreous Vancomycin Concentration After Intravitreal Injection in Uninfected Rabbit Eyes
Place holder to copy figure label and caption
Figure 3.

Intravitreal protein concentrations in uninfected eyes after injection with vancomycin hydrochloride, alone or combined with dexamethasone (n=7 per data point; values presented as mean±SEM). No statistically significant difference was found between groups based on an unpaired t test (P>.05).

Graphic Jump Location

To determine the effect of infection on the elimination of intravitreal vancomycin, intravitreal vancomycin and protein concentrations were compared between infected and uninfected eyes treated with vancomycin alone. Mean±SEM intravitreal vancomycin concentration was significantly lower in the infected eyes 72 hours after treatment (78±41 vs 120±22 µg/mL; P=.04). Mean±SEM intravitreal protein concentration was significantly higher in infected eyes 72 hours after treatment compared with uninfected eyes (24.3±8.5 vs 6.1±3.8 mg/mL; P<.001). On pharmacokinetic analysis, the infection shortened the vitreous half-life of intravitreal vancomycin from 56 to 48 hours (Table 2).

The possible benefits of intravitreal or systemic corticosteroid therapy to treat infectious endophthalmitis is an area of ongoing controversy and has yet to be shown in a prospective randomized clinical trial. However, several reports3,1316 of animal studies show that it reduces inflammation associated with the infection. In the case of pneumococcal endophthalmitis, it was previously shown3 histologically in a rabbit model that a single intravitreal injection of dexamethasone, in conjunction with vancomycin treatment, can dramatically reduce inflammation and tissue destruction associated with the infection.

In this study, we investigated whether intravitreal dexamethasone therapy may also alter the elimination of intravitreally administered antibiotic medication from the eye. Our results show that vancomycin is eliminated less readily in eyes with pneumococcal endophthalmitis when concurrently treated with dexamethasone. This corticosteroid therapy effect is correlated temporally with a reduction in intravitreal protein concentration, which is a marker of intraocular inflammation and blood-ocular barrier breakdown.5,6 Based on this observation, we speculate that the degree of breakdown of the blood-ocular barrier associated with the infection may affect the rate of vancomycin elimination from the eye. Consistent with this hypothesis, we found that, in the absence of corticosteroid therapy, the rate of elimination of intravitreal vancomycin was faster in eyes with pneumococcal endophthalmitis compared with uninfected eyes (Figure 1 and Table 2). Furthermore, results of a previous study17 show that intraocular inflammation can increase elimination of intravitreally administered antibiotic drugs if the predominant route of exit of the drug from the vitreous humor is via the anterior chamber and canal of Schlemm, as is the case with intravitreally administered vancomycin.18

Whether this decrease in the elimination of intravitreal vancomycin by corticosteroid therapy in infected eyes alters the bactericidal activity of the antibiotic drug is unknown. We did not address this question because the previous report3 using this animal model showed that rabbit eyes infected with pneumococcus become sterile within 7 days of infection, regardless of whether the eye was treated with antibiotic drugs. However, the observations made in this study are noteworthy since repeated intravitreal injection of antibiotic is frequently advocated in eyes with endophthalmitis that show minimal response to the initial antibiotic injection due to the relative rapid elimination of intravitreally injected antiobiotics from the eye.19 Unfortunately, these second injections are associated with toxic adverse effects on the retina.20,21

The second observation of this study is that the corticosteroid effect on intravitreal vancomycin elimination noted in eyes with pneumococcal endophthalmitis contrasts with that seen in uninfected eyes. As shown in Figure 1 and Table 2, an opposite effect of dexamethasone is noted in uninfected eyes. dexamethasone significantly increased the elimination of vancomycin from uninfected eyes. This observation did not correlate with changes in intravitreal protein concentration (Figure 3), and is unlikely to be secondary to an increase in intraocular inflammation resulting from additional trauma of a second intravitreal pharmacological injection. Although the exact mechanism for this observed corticosteroid therapy effect in uninfected eyes is unclear, it is similar to that reported previously12 in an animal model of Staphylococcus epidermidis endophthalmitis. In that study,12 eyes treated with intravitreal dexamethasone and vancomycin had lower vancomycin concentration than eyes treated with vancomycin alone, regardless of whether the eye was infected. The authors speculate that, because the normal route of elimination of vancomycin is anteriorly through the canal of Schlemm,18 intravitreal dexamethasone administration may facilitate this elimination in uninfected or minimally inflamed eyes. We speculate that, in eyes associated with severe inflammation due to infection with severe breakdown in the blood-ocular barrier, both anteriorly and posteriorly—as is the case in eyes with pneumococcal endophthalmitis4—the effect of intravitreal corticosteroid in reducing the blood-ocular barrier breakdown may have a more pronounced effect on the rate of elimination of intravitreal vancomycin from the eye than the possible direct effect of intravitreal corticosteroid in enhancing the elimination of vancomycin through the canal of Schlemm.

In conclusion, results of this study show that intravitreal dexamethasone treatment decreases the rate of elimination of intravitreal vancomycin from eyes with pneumococcal endophthalmitis, and enhances this rate in uninfected eyes. This observation further supports the use of intravitreal dexamethasone in the short-term management of infectious endophthalmitis that is characterized by marked inflammation on initial examination, especially when more virulent organisms are suspected to be involved, such as in cases of posttraumatic or postfiltration bleb endophthalmitides. When endophthalmitis follows cataract surgery with mild or moderate inflammation at initial examination and less virulent microorganisms may be involved, the possible effect of intravitreal dexamethasone use to enhance the rate of elimination of intravitreal antibiotic drugs from the eye should be considered.

Corresponding author: Susanna S. Park, MD, PhD, Retina Department, The Permanente Medical Group Inc, 1650 Response Rd, Sacramento, CA 95815 (e-mail: susanna.park@ncal.kaiperm.org).

Accepted for publication April 7, 1999.

Supported by a Career Development Award from Research to Prevent Blindness Inc, New York, NY (Dr Park).

Presented at the annual meeting of the Association for Research in Vision and Ophthalmology, Fort Lauderdale, Fla, April 24, 1996.

We thank the members of the clinical laboratory at Zale-Lipshy University Hospital, Dallas, Tex, for measuring vancomycin levels in the vitreous; Yogesh Mittal, MD, John Alappatt, MD, Miguel Brito, MD, Ling Li, MD, Ranjan Malhotra, MD, and Mary Payton for their help in animal experimentation; and the late Ann S. Baker, MD, for her invaluable contribution in initiating this project.

Katx  LJCantor  LBSpaeth  GL Early and late bacterial endophthalmitis following glaucoma filtering surgery. Ophthalmology. 1985;92959- 963
Mandelbaum  SForster  RKGelender  HCulbertson  WW Late onset endophthalmitis associated with filtering blebs. Ophthalmology. 1985;92964- 972
Park  SSSamily  NRuoff  KD'Amico  DJSullivan Baker  A Effect of intravitreal dexamethasone in treatment of pneumococcal endophthalmitis in rabbits. Arch Ophthalmol. 1995;1131324- 1329
Vallar  RWilson  CAPark  SS Effect of intravitreal dexamethasone on the blood-ocular barrier breakdown associated with pneumococcal endophthalmitis in rabbits [ARVO abstract]. Invest Ophthalmol Vis Sci. 1995;36(suppl)790
Csukas  SPaterson  CABrown  KBhattacherjee  P Time course of rabbit ocular inflammatory response and mediator release after intravitreal endotoxin. Invest Ophthalmol Vis Sci. 1990;31382- 387
Fleisher  LNMcGahan  MC Time course for prostaglandin synthesis by rabbit lens during endotoxin-induced ocular inflammation. Curr Eye Res. 1986;5629- 634
Williams  RNPaterson  CA PMN accumulation in aqueous humor and iris-ciliary body during intraocular inflammation. Invest Ophthalmol Vis Sci. 1984;25105- 108
Filburn  BHShull  VHTempera  YMDick  JD Evaluation of an automated fluorescence polarization immunoassay for vancomycin. Antimicrob Agents Chemother. 1983;24216- 220
Meredith  TAAguilar  HEShaarawy  AKincaid  MDick  JNiesman  MR Vancomycin levels in the vitreous cavity after intravenous administration. Am J Ophthalmol. 1995;119774- 778
Moyer  T Therapeutic drug monitoring. Tietz  Ned.Fundamentals of Clinical Chemistry. Philadelphia, Pa WB Saunders Co1987;842- 868
Bradford  MM A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976;72248- 254
Smith  MASorenson  JASmith  CMiller  MBorenstein  M Effects of intravitreal dexamethasone on concentration of intravitreal vancomycin in experimental methicillin-resistant Staphylococcus epidermidis endophthalmitis. Antimicrob Agents Chemother. 1991;351298- 1302
Coats  MLPeyman  GA Intravitreal corticosteroids in the treatment of exogenous fungal endophthalmitis. Retina. 1992;1246- 51
Graham  ROPeyman  GA Intravitreal injection of dexamethasone: treatment of experimentally induced endophthalmitis. Arch Ophthalmol. 1974;92149- 154
Meredith  TAAguilar  HEMiller  MJGardner  SKTrabelsi  AWilson  LA Comparative treatment of experimental Staphylococcus epidermidis endophthalmitis. Arch Ophthalmol. 1990;108857- 860
Peyman  GAHerbst  R Bacterial endophthalmitis: treatment with intraocular injection of gentamicin and dexamethasone. Arch Ophthalmol. 1974;91416- 418
Kane  ABarza  MBaum  J Intravitreal injection of gentamicin in rabbits: effect of inflammation and pigmentation on half-life and ocular distribution. Invest Ophthalmol Vis Sci. 1981;20593- 597
Barza  M Antibacterial agents in the treatment of ocular infections. Infect Dis Clin North Am. 1989;3533- 549
D'Amico  DJNoorily  SW Postoperative endophthalmitis. Albert  DMJakobiec  FAeds.Principles and Practice of Ophthalmology. Philadelphia, Pa WB Saunders Co1994;1159- 1169
Olson  JCFlynn  HWForster  RKCulbertson  WW Results in the treatment of postoperative endophthalmitis. Ophthalmology. 1983;90692- 699
Oum  BSD'Amico  DJWong  KW Intravitreal antibiotic therapy with vancomycin and aminoglycosides: an experimental study of combination and repetitive injections. Arch Ophthalmol. 1989;1071055- 1060

Figures

Place holder to copy figure label and caption
Figure 1.

Intravitreal vancomycin levels 24 to 72 hours after vancomycin hydrochloride injection (1 mg) (n=7 per data point; values presented as mean±SEM). A, Infected eye treated with vancomycin (1 mg) alone. B, Infected eye treated with vancomycin (1 mg) and dexamethasone (400 µg). C, Uninfected eye treated with vancomycin (1 mg) alone. D, Uninfected eye treated with vancomycin (1 mg) and dexamethasone (400 µg).

Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.

Intravitreal protein concentrations in eyes with pneumococcal endophthalmitis after treatment with vancomycin hydrochloride, alone or combined with dexamethasone (n=7 per data point; values presented as mean±SEM). Asterisk indicates a statistically significant difference from eyes not treated with intravitreal corticosteroid drugs, based on an unpaired t test (P≤.05).

Graphic Jump Location
Place holder to copy figure label and caption
Figure 3.

Intravitreal protein concentrations in uninfected eyes after injection with vancomycin hydrochloride, alone or combined with dexamethasone (n=7 per data point; values presented as mean±SEM). No statistically significant difference was found between groups based on an unpaired t test (P>.05).

Graphic Jump Location

Tables

Table Graphic Jump LocationTable 1. Vitreous Vancomycin Concentration After Intravitreal Injection in Rabbit Eyes With Pneumococcal Endophthalmitis
Table Graphic Jump LocationTable 2. Pharmacokinetic Variables of Intravitreal Vancomycin in Rabbits*
Table Graphic Jump LocationTable 3. Vitreous Vancomycin Concentration After Intravitreal Injection in Uninfected Rabbit Eyes

References

Katx  LJCantor  LBSpaeth  GL Early and late bacterial endophthalmitis following glaucoma filtering surgery. Ophthalmology. 1985;92959- 963
Mandelbaum  SForster  RKGelender  HCulbertson  WW Late onset endophthalmitis associated with filtering blebs. Ophthalmology. 1985;92964- 972
Park  SSSamily  NRuoff  KD'Amico  DJSullivan Baker  A Effect of intravitreal dexamethasone in treatment of pneumococcal endophthalmitis in rabbits. Arch Ophthalmol. 1995;1131324- 1329
Vallar  RWilson  CAPark  SS Effect of intravitreal dexamethasone on the blood-ocular barrier breakdown associated with pneumococcal endophthalmitis in rabbits [ARVO abstract]. Invest Ophthalmol Vis Sci. 1995;36(suppl)790
Csukas  SPaterson  CABrown  KBhattacherjee  P Time course of rabbit ocular inflammatory response and mediator release after intravitreal endotoxin. Invest Ophthalmol Vis Sci. 1990;31382- 387
Fleisher  LNMcGahan  MC Time course for prostaglandin synthesis by rabbit lens during endotoxin-induced ocular inflammation. Curr Eye Res. 1986;5629- 634
Williams  RNPaterson  CA PMN accumulation in aqueous humor and iris-ciliary body during intraocular inflammation. Invest Ophthalmol Vis Sci. 1984;25105- 108
Filburn  BHShull  VHTempera  YMDick  JD Evaluation of an automated fluorescence polarization immunoassay for vancomycin. Antimicrob Agents Chemother. 1983;24216- 220
Meredith  TAAguilar  HEShaarawy  AKincaid  MDick  JNiesman  MR Vancomycin levels in the vitreous cavity after intravenous administration. Am J Ophthalmol. 1995;119774- 778
Moyer  T Therapeutic drug monitoring. Tietz  Ned.Fundamentals of Clinical Chemistry. Philadelphia, Pa WB Saunders Co1987;842- 868
Bradford  MM A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976;72248- 254
Smith  MASorenson  JASmith  CMiller  MBorenstein  M Effects of intravitreal dexamethasone on concentration of intravitreal vancomycin in experimental methicillin-resistant Staphylococcus epidermidis endophthalmitis. Antimicrob Agents Chemother. 1991;351298- 1302
Coats  MLPeyman  GA Intravitreal corticosteroids in the treatment of exogenous fungal endophthalmitis. Retina. 1992;1246- 51
Graham  ROPeyman  GA Intravitreal injection of dexamethasone: treatment of experimentally induced endophthalmitis. Arch Ophthalmol. 1974;92149- 154
Meredith  TAAguilar  HEMiller  MJGardner  SKTrabelsi  AWilson  LA Comparative treatment of experimental Staphylococcus epidermidis endophthalmitis. Arch Ophthalmol. 1990;108857- 860
Peyman  GAHerbst  R Bacterial endophthalmitis: treatment with intraocular injection of gentamicin and dexamethasone. Arch Ophthalmol. 1974;91416- 418
Kane  ABarza  MBaum  J Intravitreal injection of gentamicin in rabbits: effect of inflammation and pigmentation on half-life and ocular distribution. Invest Ophthalmol Vis Sci. 1981;20593- 597
Barza  M Antibacterial agents in the treatment of ocular infections. Infect Dis Clin North Am. 1989;3533- 549
D'Amico  DJNoorily  SW Postoperative endophthalmitis. Albert  DMJakobiec  FAeds.Principles and Practice of Ophthalmology. Philadelphia, Pa WB Saunders Co1994;1159- 1169
Olson  JCFlynn  HWForster  RKCulbertson  WW Results in the treatment of postoperative endophthalmitis. Ophthalmology. 1983;90692- 699
Oum  BSD'Amico  DJWong  KW Intravitreal antibiotic therapy with vancomycin and aminoglycosides: an experimental study of combination and repetitive injections. Arch Ophthalmol. 1989;1071055- 1060

Correspondence

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).
Submit a Comment

Multimedia

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

See Also...
Articles Related By Topic
Related Topics