During a brain surgery, a team led by Dr David Langer uses a videomicroscope, which provides a magnified, high-resolution 3D image, at Lenox Hill Hospital in New York. Photograph: Beatrice de Gea/The New York Times

One blue surgical drape at a time, the patient disappeared, until all that showed was a triangle of her shaved scalp. “Ten seconds of quiet in the ro(...)