New Allegretto Wavelight Excimer Laser shows good results for hyperopia, myopia, and astigmatism!

Dear folks, if you are interested in Lasik please research the Allegretto Wavelight Excimer Laser. It is super fast and compensates for periphial vision.

Lasik University

The Allegretto excimer laser (WaveLight Laser Technologie, Erlangen, Germany) improves refractive predictability and enhances the outcome of LASIK, based on the results of a recently completed trial of the laser system in patients with myopia and myopic astigmatism, said Karl G. Stonecipher, MD.

Dr. Stonecipher

The laser received FDA approval in early October and is being marketed in the United States by Lumenis. It is approved for myopic LASIK up to 12 D of spheroequivalent (SE) and up to 6 D of cylinder as well as for hyperopic LASIK up to 6 D SE and 5 D of cylinder.

"If you end up at -1 D, it doesn't matter how many higher-order aberrations you get rid of, the patient is still seeing 20/40 and is not happy. Refractive spherocylinder outcomes must be correct," said Dr. Stonecipher, director, Southeastern Laser and Refractive Surgery Center, Greensboro, NC.

He noted that most higher-order aberrations exist in the peripheral cornea, an area that some aberrometer systems cannot image and therefore cannot treat, and that most lasers are inaccurate in the periphery. However, higher-order aberrations contribute little to most preoperative refractive errors, and attention should be directed instead to induced aberrations, particularly spherical aberrations.

"Minimizing induced spherical aberration will accomplish more than chasing small higher-order errors," said Dr. Stonecipher, a member of the WaveLight investigative group. "If we can develop a laser that will eliminate certain postoperative problems such as spherical aberration, then maybe wavefront-optimized LASIK is as good as custom LASIK."

Designed for custom ablationThe Allegretto is a flying-spot laser designed specifically for custom ablation. It has a Gaussian beam with a diameter of 0.95 mm and a tracker with a 6-ms response time. This wavefront-optimized system addresses the problem of iatrogenically induced spherical aberrations by changing the ablation profile to minimize these aberrations and adding more spots to the peripheral ablation, Dr. Stonecipher said. The laser also compensates for beam ovalization and beam reflection.

Final, 1-year myopia results of the FDA trial of the Allegretto showed that the manifest refractive predictability of all eyes ²-7 D of correction was 86% within ±0.5 D of intended correction. One-year results for 602 eyes out of 700 with ²-7 D, from an original cohort of 813, also showed a statistically significant decrease in glare and an improvement in night-driving scores when results of postoperative questionnaires were compared with responses from preoperative interviews.

Uncorrected visual acuity (UCVA) results showed that 88.6% of eyes achieved 20/20 vision, while 61.7% had reached 20/16, and 25% were at 20/12. For best spectacle-corrected visual acuity (BSCVA), three of 700 eyes (0.43%) had lost 2 lines, although no eyes lost more than that. A gain of one line or more was noted in 437 eyes.

"The high rate of improved BSCVA is a really important statistic because other lasers, even with wavefront, don't show as much gain in BSCVA," said Guy Kezirian, MD, FACS, president of SurgiVision Consultants Inc., Westlake Village, CA, which was the sponsor of WaveLight's FDA trials. "One of the things that really distinguishes this laser is the fact that eyes improved their best-corrected acuity after surgery."

Results of patient surveys also suggest that patients experienced a significant reduction in glare and fewer night-vision problems following surgery with the Allegretto laser.

On a scale of 1 to 10, patients rated their level of glare at 3.2 when measured 6 months after surgery, compared with 4.1 preoperatively and 3.4 at 3 months postoperatively (p < 0.001).

Fewer night-driving problemsThere was also a statistically significant reduction in problems reported with night-driving vision. On a scale of 1 to 10, with one being no glare and 10 being significant glare, the mean dropped from 3.7 preoperatively to 3.1 at both 3 and 6 months postoperatively (p <0.001).

"Overall, improved glare and night-vision scores were seen with the WaveLight Allegretto laser, and the difference was statistically significant (p < 0.01). However, not all eyes improved, especially those that experienced residual refractive error after surgery (p < 0.01). Pupil size correlated with worsened glare and night vision if there was residual refractive error," Dr. Kezirian said. "In eyes with a plano outcome, however, pupil size did not correlate with glare or night-driving scores. These data suggest that correction of residual refractive errors, even when the amounts are small, may result in improved glare and night vision in symptomatic patients."

Dr. Stonecipher presented results from the trial at the American Society of Cataract and Refractive Surgery meeting earlier this year; he and Dr. Kezirian subsequently provided final results to Ophthalmology Times.

Drs. Stonecipher and Kezirian also compared standard or classic LASIK, based on manifest refraction; wavefront-optimized LASIK, featuring Allegretto optimized profiles with treatment based on manifest refraction; and custom or aberrometer-based LASIK, as performed by the LADARVision excimer laser (Alcon) and the Star S4 excimer laser system (VISX). They used FDA studies of the same design to perform the comparison and limited comparisons with eyes in the same range, using 3-month data.

"Allegretto's wavefront-optimized results compared favorably with custom treatments with LADARVision and VISX for visual acuity, refractive results, and improvement in BSCVA," Dr. Stonecipher said. Comparison of aberrations could not be made since the WaveLight studies did not include these measurements.

"BSCVA results showed that 55% of eyes treated with phoropter-based wavefront-optimized ablations with the Allegretto laser gained 1 or more lines of visual acuity. With the VISX laser, 53% treated based on aberrometry (wavefront) gained 1 letter or more-a rate that is lower than the Allegretto rate for 1 line or more," Dr. Kezirian said. "With the LADARVision laser wavefront treatments, the rate for 1 line or more improvement was 31%."

Among eyes that stayed the same or gained BSCVA, Allegretto (93%) was better than VISX (89%) and LADARVision (84%). No patients treated with the VISX laser lost 2 or more lines; 0.9% of eyes treated with Allegretto lost 2 or more lines, as did 1.4% treated with the LADARVision laser.

Thank you for reading this article, We hope you enjoyed it.

Lasik Counselor

Lasik University