US extended-field-of-view imaging technology

PURPOSE: To develop an ultrasound (US) extended-field-of-view scanning technique that combines the convenience of a real-time scanner with the spatial advantages of a static B-mode scanner and provides a panoramic image in real time without position sensors or cumbersome articulated arms. MATERIALS AND METHODS: An image-registration-based position-sensing technique was used to track probe motion and reconstruct a large composite image during real-time scanning. The probe motion (translation and rotation) was estimated by combining multiple local motion vectors. This computationally intensive process required a special programmable image processor. RESULTS: Large, resolution-preserved composite images up to 60 cm long were obtained. Measurement accu racy as determined with phantom experiments was better than 5%. The method could be applied to any probe or image format. CONCLUSION: In addition to providing a panoramic image to expand diagnostic capabilities, extended-field-of-view US provides a more easily interpretable image and is an effective cross-specialty communication tool.