EyeWorld Asia-Pacific December 2012 Issue

49 EWAP PHARMA FOCUS December 2012 Scientific - from page 40 combination of belt and suspenders of besifloxacin, which gives gram- negative and good gram-positive coverage, and vancomycin is the ideal antibiotic prophylaxis for cataract surgery.” Likewise, Mark Packer, MD , clinical associate professor of ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Ore., USA, likes besifloxacin for high-risk cases, and finds it has some advantages over the other two latest generation fluoroquinolones, moxifloxacin (Vigamox, Alcon, Fort Worth, Texas, USA/Hünenberg, Switzerland) and gatifloxacin (Zymar, Allergan). “The greatest risk of postoperative infection is a broken capsule and an extended length of time for the surgery,” Dr. Packer said. “One of the reasons that I like besifloxacin is that its only use is as an eye drop so it seems the chance of a resistant organism is low.” The downside of besifloxacin can be its viscosity. “It’s a gooey emulsion, and that’s to increase the adherence to the ocular surface,” Dr. Packer said. “But it does blur vision temporarily, which is a negative for someone who just had cataract surgery.” The post-cataract “wow factor” can be impeded a bit. In higher risk cases, Dr. Packer sees this as a worthwhile tradeoff. “If you have one of these riskier cases, people understand—their expectations are quite different,” he said. In a difficult case, Dr. Packer will start besifloxacin 3 days prior to surgery and then continue this for a couple of weeks after surgery. On the other hand, in routine cases, Dr. Packer will use a generic fluoroquinolone like ofloxacin beginning 3 days before surgery and continuing it for a couple of weeks after. Dr. Packer also uses intracameral moxifloxacin in every case. He injects 0.1 cc of this diluted moxifloxacin into the anterior chamber. “That makes so much sense to me,” he said. “I feel as if I am doing the most that can be done to prevent infection.” While this approach is off-label and brings with it a potential risk of toxic anterior segment syndrome (TASS), Dr. Packer said there are several studies now in peer-review literature that point to the safety of intracameral moxifloxacin, as well as the fact that it is widely used elsewhere. “I think that is the standard for me, even though it is off-label here in the U.S.,” he said. Currently he sees the off-label status as giving practitioners some pause and creating unnecessary billing obstacles for those who embrace the approach. Dr. Donnenfeld also presses for regulatory change here to better protect high-risk patients and others. “The risk of endophthalmitis is certainly the most devastating complication of cataract surgery, and with an aging population and the lack of development of new antibiotics in ophthalmology because of the hurdles arbitrarily placed by the FDA, we are putting our patients at risk for an epidemic of endophthalmitis in the near future,” he said. Dr. Donnenfeld said he hopes that the government can be persuaded that antibiotics are a vital part of care for cataract patients. “Even though it’s an off-label indication, it’s one that should be considered important for all of our patients,” he said. EWAP Editors’ note: Dr. Donnenfeld has financial interests with Alcon, Allergan, and B+L. Dr. Packer has financial interests with Allergan and B+L. Contact information Donnenfeld: 516-766-2519, eddoph@aol.com Packer: 541-687-2110, mpacker@finemd.com regenerate. A number of studies have reported the recovery of corneal sensation after LASIK and show that recovery to normal levels takes on average 6 months. Figure 3 shows the average corneal sensation across these nine studies. In SMILE on the other hand, the anterior corneal anatomy is preserved and the anterior stromal nerve plexus is disrupted significantly less since there are no sidecuts created—no flap is created; this should result in fewer dry eye symptoms and a faster recovery of post-op patient comfort. Early results seem to support this hypothesis. We have measured corneal sensation in 39 eyes after SMILE and the results compare favorably with the average data taken from similar published LASIK studies. Corneal sensation had recovered to the baseline level by 3 months after SMILE compared with 6-12 months after LASIK. Also, corneal sensation was only slightly depressed in the majority of eyes after SMILE at the day 1 post-op visit, whereas corneal sensation was found to be generally 0 in published LASIK studies reporting 1-day data. In summary, with the introduction of the VisuMax femtosecond laser technology it has become clinically feasible to now create refractive lenticules of proper regularity with sufficient accuracy to meet and possibly exceed the accuracy of excimer laser tissue ablation for corneal refractive corrections. This enables Jose Ignacio Barraquer’s original concept of keratomileusis to be effectuated through a minimally invasive pocket incision with maximal retention of anterior corneal innervational and structural integrity. It is the final frontier in the realization of the perfect refractive surgical technique for both patients and surgeons. EWAP Editors’ note: Dr. Reinstein practices at the London Vision Clinic, London, England, UK, and is affiliated with the Department of Ophthalmology, Columbia University Medical College, New York, NY, USA, and the Centre Hospitalier National d’Ophtalmologie, Paris, France. He has financial interests with Carl Zeiss Meditec and ArcScan Inc. (Morrison, Colo., USA). References 1. Sekundo W, Kunert KS, Blum M. Small incision corneal refractive surgery using the small incision lenticule extrac tion (SMILE) procedure for the correction of myopia and myopic astigmatism: results of a 6 month prospective study. Br J Ophthalmol. 2011;95:335-339. 2. Shah R, Shah S, Sengupta S. Results of small incision lenticule extraction: All-in-one femtosecond laser refractive surgery. J Cataract Refract Surg. 2011;37:127-137. 3. Randleman JB, Dawson DG, Grossniklaus HE, McCarey BE, Edelhauser HF. Depth-dependent cohesive tensile strength in human donor corneas: implications for refractive surgery. J Refract Surg. 2008;24:S85-89. 4. Knox Cartwright NE, Tyrer JR, Jaycock P, Marshall J. The effects of variation in depth and side cut angulation in sub-Bowman’s keratomileusis and LASIK using a femtosecond laser: a biomechanical study. J Refract Surg. 2012 Jun;28(6):419-25. Contact information Reinstein: +44 207 224 1005, dzr@londonvisionclinic.com