EyeWorld Asia-Pacific December 2016 Issue

EWAP CORNEA 51 December 2016 its adherence to the cornea. Because most graft detachments occur early in the postoperative period, a long- lasting tamponade could reduce the need to reinject, or rebubble, gas into the anterior chamber. To explore the role of a different gaseous endotamponade, Dr. Sekundo relied on his experience as a vitreoretinal surgeon. “There have not been many studies investigating different endotamponade options. We used air bubble endotamponade for DMEK surgery for quite awhile and wanted to try something else. As a vitreoretinal surgeon, I decided to try a gas that is commonly implemented as a retinal tamponade, sulfur hexafluoride (SF6).” Dr. Sekundo was part of a team led by Paraskevas Ampazas, MD , that conducted a retrospective study comparing the rebubbling rate of air with SF6 in patients treated with DMEK surgery. The investigation used 5% SF6 and air in 381 consecutive patients. Two hundred of the grafted eyes received an air endotamponade and the remaining 181 grafted eyes received 5% SF6. The outcomes showed that 42 out of 200 eyes with air (21%) required rebubbling of air, while 16 out of 181 (8.8%) in the SF6 group needed rebubbling (P<0.01), demonstrating the longer- lasting effect of SF6 gas within the anterior chamber. The study is not yet published. Dr. Sekundo explained, “When you implant a graft, it can often occur that the transplant detaches and you need to put in another bubble of air or gas. When I began using SF6 gas, I initially used a higher concentration but ended up choosing a concentration between 5 and 10%.” Crucial postop hours The hours and days following DMEK surgery are crucial to graft success. For the new graft to adhere, patients should remain supine following the procedure, or be sedated for 45 minutes if unable to stay in a supine position. Because German DMEK patients are hospitalized for 3 to 4 days following surgery, their progress can be closely followed according to a strict postoperative protocol. “I perform a partial gas removal regardless of IOP. I also mark the sideport with ink for the resident on ward, and leave a written order in the chart to double check graft adherence, calling the ward myself to follow up. The second evaluation is done 4 hours after surgery. Topical steroids are used for at least 6 months postoperatively,” Dr. Sekundo said. “DMEK is currently the best choice to treat endothelial malfunction. It offers the fastest visual rehabilitation of any keratoplasty procedure to date. Final visual acuity is excellent due to minimal optical interface effects. Surgical success is dependent on experience, and there are many small steps that significantly improve outcomes. Because minimal tissue is transplanted, the risk of allograft rejection is much lower.” The indications for DMEK include Fuchs’ corneal dystrophy, pseudophakic bullous keratopathy, decompensated corneal grafts, ICE syndrome, Double protection, double safety ! Tomography Biomechanics Now, measurable biomechanics – Corvis ® ST ! Twice as much information for twice as much safety in pre-op screening for keratorefractive surgery Enhance your practice with the world’s first tonometer capable of measuring and interpreting the biomechanical properties of the cornea. In combination with the tomography values from the OCULUS Pentacam ® , it gives you maximum safety and efficiency in refractive screening. OCULUS Corvis ® ST – take care of more patients with greater safety ! Want to learn more about corneal biomechanics? Check out www.corneal-biomechanics.de for more information, scientific material and lectures from the experts. OCULUS Asia Ltd. Hong Kong Tel. +852 2987 1050 • Fax +852 2987 1090 www.oculus.de • info@oculus.hk and other causes of corneal endothelial dysfunction. EWAP References 1. Coster DJ, et al. A comparison of lamellar and penetrating keratoplasty outcomes: a registry study. Ophthalmology . 2014;121:979–87. 2. Dapena I, et al. Standardized “no-touch” technique for Descemet membrane endothelial keratoplasty. Arch Ophthalmol . 2011;129:88–94. Editors’ note: Dr. Sekundo has no financial interests related to his comments. Contact information Sekundo : sekundo@med.uni-marburg.de