Medical experts estimate there are 160 million people around the world with an unruptured intracranial aneurysm. When it breaks, more than half of those people die. The situation is frustrating for surgeons because the location of those blister-like lesions are in arteries too thin and too difficult to reach.

That may change with the development of a steerable, hydraulically actuated catheter that is thin enough to reach those small arteries. The design was inspired by flagella that allow microscopic organisms to swim but required University of California, San Diego, researchers to devise a novel technique to produce it. Mechanical Engineering Professor James Friend and Golpesh Tilvawala, who earned his Ph.D. on the project, talk about its development.