EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78719
February 2012 EW NEWS & OPINION 11 LASIK: On the Frontlines by John Ciccone ASCRS Director of Communications In the journal … February 2012 Posterior capsule striae and PCO after one-piece IOL implantation Gauri D. Shah, M.S., Abhay R. Vasavada, M.S., F.R.C.S., Mamidipudi R. Praveen, D.O.M.S., M.S., Alpesh R. Shah, M.S., Rupal H. Trivedi, M.D., M.S.C.R. The aim in this case-control study of 500 eyes was to determine how pa- tients' vision was impacted by the occurrence of intraoperative posterior capsule striae after implantation of a one-piece hydrophobic acrylic IOL. In additions, investigators looked at whether risk for posterior capsule opacification (PCO) was increased by the presence of such striae. They found such intraoperative posterior capsule striae in 13.6% of cases. In 63.2% of cases, a single stria was seen compared with multiple striae in 36.7% of eyes. At the 3-year mark, there was no significant difference in PCO scores regardless of how this was evaluated. Investigators con- cluded that in 13.6% of cases, practitioners can expect posterior capsule striae and that at the 3-year mark, this will not affect visual acuity or the development of PCO. New incisional procedure for exfoliation and POAG Jessica L.M. Ting, M.D., Karim F. Damji, M.D., Michael C. Stiles, M.D., on behalf of the Trabectome Study Group Investigators in this prospective trial set out to see how performing ab interno trabeculectomy with the Trabectome (Neomedix, Tustin, Calif.) alone or in combination with cataract surgery and IOL implantation fared for those with exfoliation glaucoma versus primary open-angle glaucoma (POAG). They determined that the mean pre-op IOP for those in the Trabectome alone group was 29 mm Hg in exfoliation cases and 25.5 mm Hg in POAG cases. One-year post-op for those in the Trabectome alone group IOP was –12.3 mm Hg in exfoliation cases and –7.5 mm Hg in POAG. Meanwhile, in exfoliation cases the cumulative probability of success was 79.1% versus 62.9% for POAG patients. When use of the Trabectome was combined with cataract surgery the mean pre-op IOP was 21.7 mm Hg in exfoliation cases and 19.9 mm Hg in POAG cases. This had dropped by –7.2 mm Hg in exfoliation cases at 1 year, which had a probability of success of 86.7% and by –4.1 mm Hg for POAG, with a success probability of 91%. Investigators concluded that IOP was safely lowered to the mid-teens with ab interno trabeculec- tomy with an overall greater reduction in exfoliation glaucoma. When this was combined with cataract surgery improved success was also seen. Review/update: Wavefront analysis and Zernike polynomial decomposition Cristina M. Oliveira, Andreia Ferreira, Sandra Franco, Ph.D. When it comes to corneal wavefront analysis the major clinical uses are of course wavefront-guided refractive surgery and new customized con- tact lens and IOL designs. Therapeutically this also can come into play for a host of issues such as conventional refractive surgery, corneal disor- ders, corneal transplantation, crosslinking therapy, incisional tech- niques, and cataract surgery and implantation of intrastromal corneal ring segments. At the mathematical heart of wavefront analysis are Zernike polynomials, which are a representation of the higher- and lower-order aberrations of the cornea. These are used to characterize individual higher-order aberrations in a familiar way. In this review, in- vestigators highlight just what is known about corneal wavefront aber- ration and how this applies therapeutically or refractively to anterior segment surgery. They also consider how this knowledge can ultimately improve outcomes. An ASCRS documentary on LASIK in the military A fter nearly 2 years of ex- tensive research and on- location filming, ASCRS has completed a television documentary on the his- tory of LASIK and laser vision correc- tion in the military. The program features a former Navy SEAL who owes his career to laser vision correc- tion and key physicians in the mili- tary who explain the important role laser vision correction plays in the lives of U.S. service men and women. The primary goal of the pro- gram is to educate the public about the safety and effectiveness of LASIK and show how, after rigorous clinical research and scientific evaluation, LASIK was accepted by the military and NASA for elite personnel who must work under the most extreme, mission-critical conditions. Addi- tionally, ASCRS wanted to showcase how the adoption of laser vision cor- rection by the Department of De- fense and NASA has created a new pool of talented and skilled men and women who want to serve in the military or NASA but were unable to due to their visual constraints. The project was funded by an unrestricted educational grant from ASCRS. Robert Watson, president of Patient Education Concepts Inc. (PEC), Houston, was selected to pro- duce the documentary, based on the company's experience with oph- thalmic patient education. The production team went to San Diego where it shot video on board the USS Midway, at the SEAL training facility in Coronado, and at the Naval Medical Center. The next two stops were Lackland Air Force base in San Antonio and the Army's base in Ft. Bragg, N.C. Additional lo- cations included Washington, D.C., as well as Clear Lake, Dallas, and Houston, Texas. "The first 8 minutes of the pro- gram were completed in April 2011 and titled 'LASIK: The Right Stuff,'" said Mr. Watson. "We presented the initial program to the ASCRS Execu- tive Committee during the ASCRS• ASOA Annual Meeting to obtain their approval of the editorial direc- tion we were taking the program. It received high marks, and some members thought the 8-minute seg- ment would make a great stand- alone program." Following approval of the editorial direction, production of the full 28-minute program went into high gear. "This program is one of the most inspiring programs I have ever watched. The impact of LASIK on our first responders and our national security cannot be overestimated," said ASCRS Executive Committee member Eric D. Donnenfeld, M.D. The film documents how re- tired Navy Capt. Steven Schall- horn, M.D., former director of Cornea Service and Refractive Sur- gery, Naval Medical Center, San Diego, and others rigorously tested laser vision correction in harsh com- bat-like environmental conditions including high altitude, extreme G- forces, underwater pressures, and blowing sand—all to simulate actual experiences that he and other mili- tary professionals have faced while on duty. He was surprised to find that many of the test subjects actu- ally performed their duties better in these conditions after having laser vision correction than before with glasses or contacts. Comprehensive clinical studies and evaluation within the Navy ulti- mately allowed PRK to be approved for ground troops and aviators. But Dr. Schallhorn's initial studies of LASIK created concerns about the in- tegrity of LASIK flaps in harsh envi- ronmental conditions and clarity of nighttime vision for aviators. How- ever, because LASIK offered a much quicker return to functional vision over PRK and less downtime for fly- ers, his team intensely studied all new technological advancements the industry offered. With the advent of custom wavefront technology, Dr. Schallhorn's studies began to show considerable improvement in the quality of night vision. But it wasn't until wavefront-guided LASIK was evaluated in combination with fem- tosecond laser flap creation that Dr. Schallhorn recommended that LASIK was finally "the right stuff" for aviators. Capt. David Tanzer, M.D., another key player on the Navy team, reported that 92% of the latest LASIK-in-aviators studies show patients achieving 20/12 or better, and 35% were 10/10 or better using the combined procedure. continued on page 12