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Printed i sed by Bausch & Lomb Incorporated. d in USA PH3467 10/10 82 Infrequent intraoperative issues found I ntraoperative complications of flap creation with the IntraLase (Abbott Medical Optics, Santa Ana, Calif.) are rare, occurring in just .37% of cases, according to James A. Davison, M.D., adjunct associate clinical professor, Univer- sity of Utah, Salt Lake City. In the November 2010 issue of the Journal of Refractive Surgery, investigators fo- cused on complications that oc- curred with the femtosecond laser during the course of 3,009 consecu- tive LASIK surgeries. Dr. Davison was one of the early users of the IntraLase. "The decision- making process in 2002 was kind of radical," he said. "We had machine numbers 21 and 22 in the country." The thinking at the time was that while they had good experiences with mechanical microkeratomes such as the Hansatome (Bausch & Lomb, Rochester, N.Y.) and the ACS (Bausch & Lomb), with no difficul- ties, it was only a matter of time be- fore a complication occurred. "We knew that our luck might not hold out of not having problems with mechanical microkeratomes because anyone can have problems with them," Dr. Davison said. "It was a technology issue and we thought that it was going to be better for pa- tients in the long run [to use the In- traLase] if we did continue to do LASIK." Prospective log From the start, he kept track of any issues that occurred with the IntraLase technology. "We kept a log of interesting and unusual things that happened that we would call intraoperative complications," he said. "Then we analyzed the cases and the results from these." When Dr. Davison reviewed the results with the IntraLase from Au- gust 2002 through July 2009, he found that there were very few is- sues, with just 11 complications over the years. "We didn't have any vi- sion-threatening complications," he said. "The most common issue was suction break." This was dealt with in a very routine manner. "We have a team of technicians who do laser all the time and they know how to reapply it. We could go ahead and reinitiate it, like it's recommended, and it worked fine," Dr. Davison said. "We didn't have to cancel pa- tients or have them come back like we do with a mechanical microker- atome." Dr. Davison had one patient, who had very unusual eyes, who was problematic. "I had one patient who had very interesting eyes be- cause they seemed to absorb the laser energy a little bit more than most and have a little bit more car- bon dioxide gas accumulate in the interface," he said. "This probably interfered with how the laser energy was absorbed." Dr. Davison found that he could barely get the patient's flaps elevated. After consulting with his partner, Dr. Davison decided to reapply the laser. "We did that and then with great effort I was able to elevate the flaps and do the case," he said. "It took me about 11 min- utes to raise one flap and 4 minutes to raise the other, while usually it takes about 10 seconds, so it was a huge effort, but it was doable." Wave of the future Using the IntraLase instead of me- chanical microkeratomes is akin to converting from extracapsular cataract surgery to phacoemulsifica- tion, to Dr. Davison's way of think- ing. "It took 20 years for that conversion to be complete but now pretty much no one does extracaps and everyone does phaco," he said. "I think that it's going to be the same thing with this because it's su- perior technology." Dr. Davison acknowledged that the IntraLase technology has its is- sues, including expense, but sees it as a worthwhile investment. "We have to purchase technology that gives better results and provides bet- ter patient care," he said. "We don't have a valet parking service, but we have this because I think that it does provide better patient care over the long term." He pointed out that anyone can have problems with LASIK. Given the procedure's elective nature, he sees this as putting more pressure on the surgeon. "Everyone thinks that LASIK is an easy thing, but there is a certain amount of anxiety when you sit down with someone with an oth- erwise normal eye and you're going to do something to it," Dr. Davison said. "You take on a certain amount of risk with that." Overall, Dr. Davison sees the femtosecond technology as an excel- lent addendum in forestalling LASIK complications. "If you can acquire the technology at a reasonable price and if you can create a discipline to use the technology to avoid cata- strophic complications, then it's going to be a good thing," he said. EW Editors' note: Dr. Davison has financial interests with Alcon (Fort Worth, Texas). Contact information Davison: jdavison@wolfeclinic.com EW REFRACTIVE SURGERY 82 March 2011 by Maxine Lipner Senior EyeWorld Contributing Editor Considering femtosecond flap complications An example of the IntraLase procedure Source: Perry S. Binder, M.D. Straylight relationships continue to puzzle researchers R esearchers who set out to find the influencing factors of stray- light before and after LASIK discovered that the perplexing phenomenon had no correlation with specific optic parame- ters such as refractive power, keratometric value, corneal cen- tral thickness, and anterior chamber depth, according to a study published in February in the online version of Investigative Ophthalmology & Visual Science. In the prospective, non-randomized study conducted at the Tianjin Eye Hospital & Eye Institute, Tianjin, China, 105 eyes of 105 patients were examined. Straylight levels were measured with a straylight meter (C-Quant, Oculus, Lynnwood, Wash.), and relationships with the afore- mentioned optic parameters were analyzed in normal, young, myopic eyes. The difference between post-op and pre-op straylight and the rela- tionship with ablation were studied before and 1, 4, and 10 months after LASIK surgery was performed. "For normal eyes, sphere, astigmatism, K value, CCT and ACD showed no significant correlation with straylight; however, straylight values showed a statistically significant increase one and four months postoperatively (P<0.05) but returned to preoperative levels at 10 months postoperatively (P>0.05) in LASIK eyes," the study authors re- ported. Researchers also could not find a statistically relevant relationship between straylight values, ablation depth, ablation ratio, residual bed thickness, or RBT/CCT post-op.

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