Combined femtosecond, excimer laser produces premium LASIK results

The femtosecond laser is used for flap creation, while the excimer laser is used for photoablation.

The combination of Ziemer Femto LDV femtosecond laser for flap creation and Schwind Amaris excimer laser for photoablation resulted in optimal visual and refractive outcomes in a large number of patients, according to a surgeon.

“Results were remarkable 1 day after LASIK and throughout the follow-up. These two lasers make the perfect combination,” Minoru Tomita, MD, said at the meeting of the European Society of Cataract and Refractive Surgeons in Paris. In 2009, Dr. Tomita received the Schwind Amaris Award and the Ziemer Award for the highest treatment volume worldwide.

A total of 1,000 eyes of 526 highly myopic patients with a mean age of 35 years were treated between August 2009 and January 2010. Preoperative mean uncorrected visual acuity was 20/250 and mean manifest refraction spherical equivalent was –5.12 D. Thin 90-µm flaps were performed in all patients, and the “aberration-free” program was used for laser ablation.

At 3 months, 98% of the patients had achieved UCVA of 20/20 or better, and 100% were 20/20 or better with correction. The manifest refraction spherical equivalent was within 1 D of intended correction in 99% of patients.

“Safety index and efficacy index were very good, and no complications occurred during surgery,” Dr. Tomita said.

Femtosecond laser

The Femto LDV femtosecond laser has a spot size of less than 2 µm and a repetition rate of more than 1 MHz. Pulse energy is nearly 100 nJ.

“The combination of low pulse energy with high repetition rate produces a smooth stromal surface, preserving normal tissues and fibers,” Dr. Tomita said. “The low pulse energy also reduces the incidence of the typical complications of femtosecond laser ablation, such as inflammation, transient light syndrome, diffuse lamellar keratitis and opaque bubble layer.”

Excimer laser

The Amaris excimer laser has unique features for safety and high-quality performance, Dr. Tomita said.

It works at a high speed, with a repetition rate of 500 Hz, but a significant reduction of corneal heating can be obtained by using an “intelligent treatment effect control” program.

“The adapted distribution of laser pulses during the treatment provides time between the pulses, allowing for each area to cool down,” he explained.

It has a unique, high-speed, six-dimensional eye tracker that is more than twice as fast as the laser and tracks all possible eye movements — along the x, y and z axes, as well as rolling and cyclotorsion.

“It is more than twice as fast as the laser and it allows for the creation of accurate, perfectly centered ablations,” Dr. Tomita said.

It has two automatically adapted fluence levels to vary the amount of laser energy delivered to the eye during the treatment.

“In the first 80% of the ablation, it works with high speed and high power to produce fast ablation of a large area and automatically switches to lower power in the last 20% to create a smooth surface,” Dr. Tomita said.

Finally, an aberration-free program minimizes the induction of aberrations.

Unlike other femtosecond LASIK procedures, this combination does not require the patient to be moved during surgery.

“It’s the femtolaser to be moved,” Dr. Tomita said. “The Ziemer LDV is on wheels and can be transported to the operating table without resetting. The entire operation is conducted under the same microscope.”

Treatment time is short and comfortable for the patient.

“I offer this combination of Ziemer LDV and Amaris as a premium treatment. The cost is slightly higher, but patients are willing to pay the extra price for premium results. [Because] the patients are very satisfied with their outcomes, it is easy to get referrals, and the process simply repeats itself with new patients,” Dr. Tomita said. – by Michela Cimberle

• Minoru Tomita, MD, can be reached at Shinagawa LASIK Center, Yurakucho Itocia 13-15F 2-7-1 Yurakucho, Chiyoda-ku, Tokyo 100-0006 Japan; 81-3-5221-2207; fax: 81-3-5221-8138; email: tomita@shinagawa.com.

I fully confirm what the author says: The combination of the Amaris excimer laser and the LDV femtosecond laser is offering outstanding results with a high degree of patient satisfaction. Despite the slightly higher costs, an increasing number of patients choose this premium treatment and recommend it to others.

Not only the time of ablation but also the overall procedure time are shorter and allow a very efficient work flow. The combination of the two lasers does not require the patient to be moved during surgery, which is a further advantage for both patients and surgeons.

Despite the excellent outcomes, research should be continued. We should always aim at improving what we already have, not only in terms of clinical outcomes, but also as far as ergonomics, complications, environmental burden during production, usage and many other aspects are concerned.

– Maria Clara Arbelaez, MD
Muscat Eye Laser Center, Muscat, Oman
Disclosure:Dr. Arbelaez receives occasional travel expenses from Schwind and Ziemer.