An augmented reality system for ultrasound guided needle biopsies.

We have developed an augmented reality visualization system that helps the physician perform ultrasound guided needle biopsies. For a needle biopsy, the needle has to be inserted into an anatomical target to remove a tissue sample. Ultrasound guidance is routinely used e.g. for breast needle biopsies. The real-time ultrasound images allow the physician to locate the target and to monitor the needle position. Our system uses a combination of an optical laser guide and a virtual guide in the augmented image to provide intuitive guidance for the needle placement. There is no need to track the needle, i.e. there is no need to instrument the needle for tracking. In phantom tests, users have performed well with the system without prior training. This paper describes special features of our system and the workflow for the needle placement procedure.