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Allegretto Wave hyperopic LASIK accurate with little regression
Hyperopic LASIK using the Allegretto Wave was successful in treating low and high hyperopia.
Wavelight LASIK to correct hyperopia and hyperopic astigmatism with the Allegretto Wave laser demonstrated a high degree of accuracy and little regression in a multicenter clinical study.
Charles R. Moore, MD, presented the study results at the American Society of Cataract and Refractive Surgery meeting.
“In terms of stability, Allegretto Wave hyperopic treatments achieved less than half the regression reported [in earlier studies], and postoperative quality of vision results were superior in all respects,” the study concluded.
The study
Dr. Moore looked at 290 hyperopic and hyperopic astigmatic LASIK treatments performed with Wavelight’s Allegretto Wave at 10 centers for Food and Drug Administration premarket approval.
“We went back and reviewed, recalled the patients and reviewed the data now compared to what it was back then in the original study,” Dr. Moore told Ocular Surgery News in a follow-up interview. “All these were patients that participated in the original FDA study with 10 different sites.”
All of the patients had been living with their treatments for more than 3 years. They ranged up to 6.5 D spherical equivalent.
Initially, after 3 months, patients showed a mean regression of 0.12 D and 0.01 D thereafter, Dr. Moore said. This study was an attempt to look at long-term stability after 3 to 4 years, he said.
“We broke the categories down into three separate groups of 0 D to 2 D, 2 D to 4 D, and 4 D to 6 D. All patients received a 6.5-mm optical zone ablation with adjustable blend out to 9 mm,” he explained.
Sixty percent of patients were within the 0 D to 2 D range, 28% were between 2 D to 4 D, and 12% fell between 4 D and 6 D.
Conclusions
With a mean follow-up of 3.7 years, Dr. Moore said there was no significant regression for patients receiving treatment for less than 4 D and a “tolerable” amount of regression for more than 4 D; stability and predictability were good.
“This shows with the large optical zone that the Allegretto produces, you not only get tremendous reduction in the regression that’s been reported previously in the literature, but you also get a better depth of focus,” Dr. Moore said.
Postoperative uncorrected visual acuity of 20/40 or better was achieved in 95.4% of patients. More than 65% were 20/20, and more than 29% achieved 20/16. One or more lines of best corrected visual acuity were gained by 40.8%, while 10.1% gained two or more lines.
Attempted vs. achieved predictability spheroequivalent for all eyes was 71.9% within ±0.5 D and 90.2% within ±1 D. Glare reduction postoperatively was statistically significant.
“It’s 10 times faster than most other lasers to treat hyperopia, and I think that’s one of the reasons the results are so predictable,” Dr. Moore said. He explained that a patient suffers less tissue dehydration and, therefore, less erratic results.
“The refractive changes correlated best with the keratometric changes in the higher hyperopes – the 4 D to 6 D group – so this implied after 3 years some true regression, but less than 0.5 D,” Dr. Moore said.
“The refractive differences correlated best with the untreated hyperopia or the latent hyperopia in the lower hyperopic groups, suggesting latent hyperopia becoming manifest 3 years later, which was not a surprise,” he said.
Overall, regression occurred more often in higher hyperopes, but it was less than 0.5 D after at least 3 years.
“In conclusion, there was no significant regression seen in less than 4 D and a very tolerable amount over 4 D at the 3.7-year mark, which suggests good stability with hyperopic LASIK using the wider ablation zones and the wavefront optimized profile,” Dr. Moore said.
In comparison to previous studies, he said, “It may suggest that the older broad-beam lasers just didn’t have large enough optical zones to create good stability.”
Previous studies
In previous studies of hyperopic LASIK, there are few showing strong performance or with long-term follow-up, Dr. Moore said.
“Hyperopic LASIK literature reports vary in their conclusions of hyperopic stability — some platforms showing good, long-term stability and many reporting very poor long-term stability,” he said. “Comparisons also vary with older lasers, smaller optical zones and treatment ranges. There are very few reports in the literature with follow-ups more than 1 year.”
“In the literature previous to now, there have been no long-term good results that didnt have significant regression, Dr. Moore said.
For more information:
- Charles R. Moore, MD, can be reached at International Eye Center, 926 N. Wilcrest, Houston, TX 77079; 713-984-9777; fax: 713-984-8768; e-mail: drmoore@texaslasik.com.
- Wavelight Laser Technologies AG, maker of the Allegretto Wave laser, can be reached at 46040 Center Oak Plaza, Sterling, VA 20166; 571-434-8500; Web site: www.wavelight-laser.com.
- Katrina Altersitz is an OSN Staff Writer who covers all aspects of ophthalmology.