Latest technology allowing laser vision correction in naval aviators

SAN DIEGO — The combination of wavefront-guided technology and femtosecond flap creation has produced such positive clinical results that certain naval aviators may now undergo LASIK, according to a surgeon speaking here.

Steven C. Schallhorn, MD, presented an overview of the evolution of refractive surgery in the U.S. Navy during the Cornelius D. Binkhorst Lecture at the American Society of Cataract and Refractive Surgery's opening session.

Dr. Schallhorn and his colleagues have conducted numerous studies since the 1990s to ascertain which procedures and technology produced the best clinical results, he said.

They learned from their initial studies that conventional LASIK induced a non-recoverable decrease in contrast sensitivity. In a further comparative study, he found this decrease was five times less pronounced with wavefront-guided LASIK.

In a second comparative study, Dr. Schallhorn found that femtosecond laser-created flaps led to faster visual recovery and better contrast sensitivity than microkeratome-created flaps, he said.

In night driving tests, which mimic aircraft landing scenarios, naval aviators who were treated with femtosecond-assisted wavefront-guided LASIK demonstrated an improvement in their performance. In contrast, those aviators who underwent conventional, microkeratome-assisted LASIK experienced, on average, a decline in performance, he said.

As a result of these studies, the U.S. Naval Medical Center now performs LASIK with a VISX STAR S4 CustomVue laser platform and the IntraLase femtosecond laser (Advanced Medical Optics), he said.

In 2006, the U.S. Naval Medical center performed LASIK on the first naval aviator in history. Within 4 hours postop, he had achieved a UCVA of 20/20. By the next day, his UCVA had improved to 20/16.

Naval aviators can typically return to the cockpit by 1 month postop, Dr. Schallhorn said. Ongoing studies will look at ways to reduce this recovery time to 1 to 2 weeks, he said. Shorter recovery times could translate into cost savings, he said.

He noted that astronauts are the "final frontier" in personnel restricted from LASIK. The military is currently working with NASA on this issue with the hope of introducing laser vision correction to astronauts in the near future, he said.