DEC 2013

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

Issue link: https://digital.eyeworld.org/i/227001

Contents of this Issue


Page 55 of 74

November 2013 are more likely with Fuchs' and no preoperative glaucoma," said Ed Holland, MD, Cincinnati. Additionally, while there was significant cell loss (around 76%) in all groups, "this seems to level off after five years." Grafts with endothelial cell counts of 1500 or more had a 2% risk of failure between years five and 10, but those with ECDs under 500 had a 29% risk of failure. "Donor age should not be a factor in transplantation," Dr. Holland said. Single-pass ultra-thin grafts and eye bank preparation Using a single-pass technique to prepare donor tissue leaves a "slightly thicker periphery," said Erkin Abdullayev, MD, Tampa, Fla., which may be beneficial in preserving endothelial cell density (ECD) during the life of the graft. A retrospective analysis of 199 consecutive grafts prepared by an eye bank with a standard microkeratome had an average ECD count of 3097 before the cut and a central corneal thickness (CCT) of 490 microns. Post-cut, the ECD was 3059 microns and the CCT was 81 microns. A total of 35 surgeons used the grafts (surgeons were in the U.S. and 12 other countries). There was one primary graft failure, five interface hazes, and three technical difficulties with insertion. "These grafts can be safely prepared in the eye bank with no increased risk of perforation and endothelial cell loss," Dr. Abdullayev said. Steroid cessation linked to graft rejection Overall rejection rates after DSAEK in patients with Fuchs' endothelial dystrophy can be reduced with continued steroid use, said Kevin Shah, MD, Cincinnati. In his retrospective study on 400 patients with Fuchs' and an average follow-up of 38 months, the overall rate of rejection was 4.3% (n=17), with most rejections occurring between months 24 and 36. "Our rejection rate was really low, which may be reflective of our patient population only including Fuchs,'" he said. "But 50% of those rejections were in eyes that had completely stopped topical therapy." Dr. Shah said that regardless of transplant technique, chronic steroid use is highly recommended. During the audience Q&A, it was also suggested (with anecdotal evidence) that graft patients increase their steroid use to four times daily one or two days before receiving a flu shot, and continue the higher dosage for 2–3 weeks after receiving their shot. Steroid choice is not as important as therapy maintenance, he said. Future of phakic IOLs uncertain The future of phakic IOLs is unknown, as they currently offer excellent refractive results but have long-term complications, Antonio A.P. Marinho, MD, Porto, Portugal, said. Dr. Marinho delivered the Keynote Lecture "Phakic IOLs: Where are we heading?" at the Refractive Surgery 2013: Perfecting Vision Subspecialty Day. The talk followed "Section II: Phakic IOLs," which featured presentations on the lenses from four physicians including Alaa M. Eldanasoury, MD, Jeddah, Saudi Arabia, and Thomas Kohnen, MD, Frankfurt, Germany. They discussed topics related to phakic IOLs including type of lens and safety profiles. "We need phakic IOLs because corneal laser surgery has limits because of biomechanics of the cornea, and we all know about regression, ectasia, and loss of quality of vision in high ametropes," Dr. Marinho said. He said the lenses are necessary now because they have high predictability even in high ametropia cases. He answered the question "are phakic IOLs safe?" by saying that, although phakic IOLs have excellent refractive results, there are long-term complications with the lens design. Those occur because the phakic IOL is placed in the "top of the normal structures of the eye, so there is an intimacy of the phakic IOL with the different structures of the eye. This is what causes the complications," he said. Five challenges exist with phakic IOLs: the sizing of the IOL, location related to the anterior vs. posterior chambers, IOL material, range of correction, and surgical technique, Dr. Marinho said. These factors can impact the overall results and complication rates with the lens, he said. Whether or not there is a future for phakic IOLs is undetermined, he said. "Are we going to discuss, here, phakic IOLs in 15 or 20 years' time?" he asked. "It's impossible to guess. However, the problem of the intimacy with ocular structures will remain." Ultimately, phakic lenses might not be needed decades from now if what Dr. Marinho called the "refractive surgeon dream" happens and lens surgery develops considerably into the future. Editors' note: Drs. Eldanasoury, Kohnen, Marinho have no financial interests related to their presentations. EW MEETING REPORTER 53 Corneal collagen crosslinking Refractive Subspecialty Day began with a session devoted to corneal collagen crosslinking, a highly debated topic. Theo Seiler, MD, Zurich, gave the keynote for the session on "Crosslinking: Inception to Multiple Clinical Application." He broke down crosslinking into four main points: definition, biomechanical action, biochemical action, and cytotoxic action. Dr. Seiler also served as a moderator and speaker in the corneal crosslinking session, where he discussed safety, efficacy, stability, and long-term results. Paolo Vinciguerra, MD, Milan, discussed the concentration of riboflavin in the cornea. If there is poor riboflavin concentration, there are ways to improve this, he said. Some of the ways to improve this problem include using epi-off, increasing concentration and increasing soaking time. The way that Dr. Vinciguerra highlighted, however, was iontophoresis. Dr. Vinciguerra's presentation defined iontophoresis as a non-invasive technique in which a small electric current is applied to enhance ionized drug penetration into tissue. So far preliminary outcomes seem continued on page 54 Scan QR code to go to EWrePlay.org Kazuo Tsubota, MD, Tokyo, (right) explains the wavelengths associated with diurnal rhythm and why LED lighting may be interfering with our sleep to Joshua Young, MD.

Articles in this issue

Links on this page

Archives of this issue

view archives of Eyeworld - DEC 2013