Eyeworld

EW NEWS & OPINION 21 ferent mutation sites were detected at 3 weeks," Dr. Miyanaga reported. "Our study also showed that the rates of resistance to various fluoro- quinolone agents in the S epidermidis strains isolated after 3-week continu- ous instillation of levofloxacin reached 73.3% to 86.7% (versus 26.7% to 46.7% before instillation). These results suggest that long-term prophylactic instillation of lev- ofloxacin may increase the risk for endophthalmitis as a result of the emergence of fluoroquinolone-resis- tant bacteria." Gatifloxacin operated differ- ently. "There were no increases in the resistance rate to fluoro- quinolone after instillation, unlike in the levofloxacin group, and bacte- ricidal effects were observed after in- stillation in 1 patient with high-level fluoroquinolone-resistant strains de- tected before antibiotic instillation," Dr. Miyanaga noted. "These results suggest that gatifloxacin had better bactericidal effects against S epider- midis than levofloxacin and a lower risk for inducing microbial substitu- tion to fluoroquinolone-resistant strains." Dr. Miyanaga suggested the bet- ter performance of gatifloxacin in terms of preventing resistance could be attributed to the fact that it in- hibits two enzymes (DNA gyrase and topoisomerase IV), "and has more potent bactericidal effects than lev- ofloxacin, which mainly inhibits topoisomerase IV." However, one strain of bacteria detected before antibiotic use demonstrated a high level of resist- ance against both fluoroquinolones, as well as others tested. "Strategies for the prevention of antibiotic re- sistance are important," Dr. Miyanaga stressed. Japan's culture currently in- volves long-term use of antibacterial prophylaxis after surgery, which may be a cause for concern. "A ques- tionnaire sent to members of the Japanese Society of Cataract and Re- fractive Surgery in 2005 found that the most common duration of anti- bacterial eyedrop use after surgery was 1 month (34%), followed by 3 months (33%)," Dr. Miyanaga re- ported. Again, even 3-week continuous use of antibiotics can cause resist- ance to emerge, as Dr. Miyanaga demonstrated with levofloxacin in this study. "Long-term preventive administration of antibacterial eye- drops may result in resident bacteria developing resistance to the agent," he concluded. Francis S. Mah, M.D., co-med- ical director, Charles T. Campbell Ophthalmic Microbiology Labora- tory, University of Pittsburgh School of Medicine, suggested there's cause for concern about resistance to an- tibiotics, but also that resistance may not be as bad as statistics indi- cate. "In our lab we have anywhere from 30-75% efficacy of fourth-gen- eration fluoroquinolones against Staphylococcus aureus and coagulase- negative Staphylococcus," Dr. Mah said. "In truth, we're not having all those failures." Dr. Mah suggested the standard way the scientific community meas- ures resistance—based on data that is not eye-specific—means the figures are actually more damning than in actual practice, where concentrations of topical antibiotic allow them to kill bacteria efficaciously. EW Editors' note: Dr. Mah has no financial interests related to his comments. Dr. Miyanaga has no financial interests re- lated to this study. Contact information Mah: 412-647-2211, mahfs@upmc.edu Miyanaga: miyanaga-tmd@umin.ac.jp D.O.R.C. International B.V. Scheijdelveweg 2 3214 VN Zuidland The Netherlands Phone: +31 181 45 80 80 Fax: +31 181 45 80 90 E-mail: sales@dorc.nl Dutch Ophthalmic USA 10 Continental Drive Bldg 1, Exeter, NH 03833, U.S.A. Phone: +1 800-75-DUTCH or +1 603-778-6929 Fax: +1 603-778-0911 E-mail: sales@dutch ophthalmicusa.com MEMBRANEBLUE TM 0.15% Trypan Blue Ophthalmic Solution INDICATIONS FOR USE MembraneBlue ™ is indicated for use as an aid in ophthalmic surgery by staining the epiretinal membranes during ophthalmic surgical vitrectomy procedures, facilitating removal of the tissue and reducing the risk of retinal damage. Staining also reduces the chance of incomplete peeling of the membrane, which could lead to persisting metamorphopsia. The application of MembraneBlue ™ onto the ILM or the ERM resulted in a useful bluish staining, facilitating the identification, delineation, and removal of the membranes in all surgeries. No residual staining or adverse effects related to MembraneBlue ™ were observed. 1 MembraneBlue ™ staining of the internal limiting membrane, epiretinal membranes, and the posterior hyaloid is a useful adjunct in vitreoretinal surgery and improves the efficiency and safety of membrane identification and removal. 2 SPECIAL CONSIDERATIONS It is recommended that after injection all excess MembraneBlue ™ is immediately removed from the posterior chamber of the eye. MembraneBlue ™ is contraindicated when a non-hydrated, hydrophilic acrylic lens is planned to be inserted into the eye. Adverse reactions reported following use of MembraneBlue ™ include discoloration of high water content hydrogen IOLs and inadvertent staining of the posterior lens and vitreous face, which is generally self-limited, lasting up to one week. NOW AVAILABLE TO US SURGEONS Please see adjacent page for brief prescribing information. 1. Teba FA, Mohr A, Eckardt C, Wong D, Kusaka S, Joondeph BC, Feron EJ, Stalmans P, Van Overdam K, Melles GRJ. Trypan blue staining in vitreoretinal surgery. Ophthalmology 2003; 110(12):2409-12. 2. Vote BJ, Russell MK, Joondeph BC, Trypan Blue-Assisted Vitrectomy, Retina 2004; 24(5):736-8. D.O.R.C. International B.V. Scheijdelveweg 2 3214 VN Zuidland The Netherlands Phone: +31 181 45 80 80 Fax: +31 181 45 80 90 E-mail: sales@dorc.nl Dutch Ophthalmic USA 10 Continental Drive Bldg 1, Exeter, NH 03833, U.S.A. Phone: +1 800-75-DUTCH or +1 603-778-6929 Fax: +1 603-778-0911 E-mail: sales@dutch ophthalmicusa.com ERGONOMICALLY DESIGNED, PRECISION ENGINEERED TO GIVE YOU AN ADVANTAGE. See what other advantages D.O.R.C. can offer you! INNOVATION WITH AN ADVANTAGE... THE D.O.R.C. ADVANTAGE Until now, disposable microforceps and scissors have fallen short of achieving the same level of action and performance as reusable instruments. The Dutch Ophthalmic Research Center, the first to develop disposable instruments, now offers you a distinct advantage in disposable instrumentation. The D.O.R.C. Advantage line has been clinically engineered to overcome the functional limitations of existing disposable instruments while delivering maximum performance and functionality. A recent study examined the impact of gatifloxacin and levofloxacin eyedrops on S. epidermis, which frequently causes post-op endophthalmitis (pictured here) Source: Daljit Singh, M.D. April 2011

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