Conventional LASIK affects night-driving performance

April 18 - Washington, DC - Conventional LASIK for moderate myopia generally reduces night-driving performance, but the frequency of that effect differs between laser platforms, said Steve C. Schallhorn, MD.

He reported results from a study in which 75 patients were randomized to conventional myopic LASIK with one of four lasers: a VISX system, the Technolas 217 (B&L), the EC-5000 (Nidek), or the LADARVision 4000 (Alcon Laboratories).

Only patients with between -5 and -6 D of myopia were included. All underwent testing with a night driving simulator preoperatively and at 6 months after surgery. A series of 144 threshold measurements were made in each patient with each eye tested separately to detect and identify three different road hazards with and without a glare source.

For change in detection, patients who were treated with the Alcon or VISX lasers had less performance loss from pre- to postoperatively relative to the B&L and Nidek groups. Loss in ability to identify road hazards was least in the VISX group compared with the other three laser groups, which were all associated with similar changes in performance.

"Based on metrics provided by the National Highway Traffic Safety Administration, the decrement in night-driving performance occurring after LASIK would be clinically relevant in between 20% and 50% of the patients in the four treatment groups," Dr. Schallhorn said.

Dr. Schallhorn has no financial interest in any of the technology he discussed.