WASHINGTON (Reuters) – An experimental stroke treatment that sends laser beams into the brain may help patients with milder strokes lessen their crippling effects, US researchers said yesterday.

Carlsbad, California-based PhotoThera Inc's NeuroThera Laser System failed to significantly lower stroke disability overall in 660 stroke patients in its first major clinical trial, the researchers wrote in the journal Stroke.

But patients with moderate to moderately severe strokes did improve after laser treatment, the researchers said.

Stroke is the number three cause of death in the United States and a leading cause of disability, and experts say new stroke treatments are urgently needed.

Doctors used the laser device to painlessly send low-energy infrared radiation into the brain, on average 14-½ hours after a stroke.