A new concept for a real-time ultrasound transmission camera

Ultrasound transmission imaging is an alternative promising modality because unlike x-ray transmission this concept is not ionizing and has a good contrast in tissue imaging. Our concept enables also real time imaging. Earlier designs of transmission cameras with a 2D-array and an acoustic lens suffered from high costs, large size and a limited imaging quality, which finally caused those cameras not to become a commercial product. We developed a novel compact low-cost ultrasound transmission camera. With a center frequency of 3 MHz a resolution of 1 mm in both lateral dimensions was achieved over a field of view of 80/spl times/80 mm/sup 2/. Real time images of moving joints and tendons are displayed with a frame-rate of 25 1/s. The major fields of application are orthopedics, pediatrics and diagnosis of rheumatic arthritis.