EyeWorld Asia-Pacific September 2013 Issue

59 EW PHARMACEUTICALS September 2013 patients on Coumadin (warfarin, Bristol-Myers Squibb, New York, NY, USA), as well as one-eyed individuals. Likewise, patients with posterior staphylomas are not good candidates, since this puts them at an approximately nine- fold increased risk of intraocular perforation. This is something most likely to occur in myopes, Dr. Arbisser noted. “Whoever is doing an injection needs to be well aware that it’s a longer eye and be very sensitive about the angle that they use,” she said. As part of her regional regimen, Dr. Arbisser gives a single peribulbar injection administered inferior, through the cul-de-sac only, of no more than 5 cc of a mixture of lidocaine 2% with epinephrine and hyaluronidase. The addition of the hyaluronidase helps the medication spread through the tissue planes in order to get full akinesia. There is some evidence that this reduces the toxicity of the lidocaine to the extraocular muscles since it spreads what otherwise would be a concentrated lump through the tissues, she explained. In addition to giving all patients IV-systemic sedation with a little versed and dilute alfentanil (Alfenta, Akorn, Lake Forest, Ill., USA), Dr. Arbisser relies on what she dubs “vocal local” to empower them. “What I always say at the beginning of the case is, ‘You’ll be aware of my presence, but you’ll feel no pain. And if anything bothers you, just tell me and we’ll do something about it right away.’” It is then important to follow through with that promise, she noted. When using peribulbar or retrobulbar techniques, Dr. Arbisser stressed the need to avoid multiple injections. “I virtually never supplement an injection because I think the risk is higher than the benefits,” she said. Another possible option is use of sub-Tenon’s injections, commonly used in the U.K. This may have greater efficacy than the topical approach and is safer than the intraocular one, believes Scott Greenbaum, MD , Greenbaum Eye Associates, and clinical assistant professor of ophthalmology, New York University Medical Center, New York, NY, USA. Sub-Tenon’s gives amaurosis—the inability to see the operating room microscope. “This is an underappreciated benefit of sub-Tenon’s anesthesia because it provides so much more comfort to the patient,” Dr. Greenbaum said. This approach also provides some akinesia, he noted. When compared to retrobulbar and peribulbar, Dr. Greenbaum views the sub- Tenon’s technique as “infinitely safer.” “If you use, for example, my plastic cannula [Greenbaum Anesthesia Cannula, Alcon, Fort Worth, Texas, USA/Hünenberg, Switzerland], it’s short, it’s blunt, it’s flexible, and you’re not going to penetrate the eye with it,” Dr. Greenbaum said. “If you use other short, blunt anterior sub-Tenon’s cannulas, it’s the same thing.” However, long metal cannulas can damage the optic nerve and extraocular muscles, he observed. “The risk of perforating the eye with a needle with a peribulbar or retrobulbar technique is much greater,” Dr. Greenbaum said. The same medications injected with other regional techniques are used here. Dr. Greenbaum uses 0.75% bupivacaine, 4% lidocaine, and Hylenex (hyaluronidase, Halozyme Therapeutics, San Diego, Calif., USA). “All three [regional techniques] will give the same effect, it’s just the safety of sub-Tenon’s is much better,” Dr. Greenbaum said. Dr. Greenbaum doesn’t think that general anesthesia is indicated anymore. “With sub- Tenon’s, it’s such a safe, effective technique, I’ve not had, except for pediatric cases, a need to put anyone under general anesthesia,” he said. Dr. Arbisser, meanwhile, reserves this for children, for those who cannot control themselves, as well as rarely a one-eyed patient or particularly complex case. Dr. Gills believes that physicians should use their discretion here. He pointed to a practitioner he knows who has an assistant with a very calming presence, thereby enabling him to use minimal anesthesia. His own assistant’s in-charge approach, while efficient, doesn’t allow for this. “I think physicians should be free to do what in their hands is good—everybody has to do what they think is sincerely the best for their patients,” he concluded. EWAP Editors’ note: Dr. Arbisser and Dr. Gills have no financial interests related to this article. Dr. Greenbaum has financial interests with Halozyme Contact information Arbisser : 563-323-2020, drlisa@arbisser.com Gills : 727-938-2020, jgills@stlukeseye.com Greenbaum : 718-897-2020, thecannula@aol.com Digital Photography Solutions for Slit Lamp Imaging Digital Photography Solutions Digital Eyepiece Camera Fundus Camera upgrades Digital SLR Camera Upgrades Image Capture Soft FDA cleared EMR/EHR interface DICOM compatible Visit us @ ASC RS in San Francisco booth # 2712 Digital SLR Camera Upgrades Ma TTI Transamerican Digital Fundus Camer upgrades Di Ca Visit us @ ASCRS in Sa Digital Eyepiece Camera Image Capture Software FDA cleared EMR/EHR interface DICOM compatible Made in USA TTI Medical Transamerican Technologies International Digital Photography Solutions Digital Eyepiece Camera Fundus Camera upgrades Digital SLR Camera Upgrades Toll free: 800-322-7373 email: info@ttimedical.com www.ttimedical.com Image Capture Software FDA cleared EMR/EHR int rface DICOM compatible Visit us @ ASCRS in San Francisco booth # 2712 Come visit us @ AAO in New Orleans, booth # 4231 Made in USA TTI M dical Transamerican Technologies International Toll free: 800-322-7373 email: info@ttimedical.com www.ttimedical. om