Ultrasound scanning could be used to diagnose stroke victims faster, and may even one day be used to check the head injuries of sport stars while they are still on the field.

Ultrasound produces pictures of a body’s insides by transmitting and recording the echoes of sound waves. It is most commonly used to measure the size of fetuses during pregnancy. Lluís Guasch at Imperial College London and his colleagues have now developed a version that produces three-dimensional ultrasound images of the human brain

Guasch hopes it …