Acoustic shadows appear in ultrasound images as regions of low signal intensity after boundaries with very high acoustic impedance differences. Acoustic shadows can be viewed as informative features to detect lesions or calcifications, or can be considered as damageable artifacts for image processing tasks such as segmentation, registration or 3D reconstruction. In both cases, the detection of these acoustic shadows is useful. This paper proposes a new geometrical method to detect these shadows based on statistical analysis of intensity profiles along the lines that compose the B-scan image. The results demonstrate that this detection improves the accuracy of 3D reconstruction of intraoperative ultrasound.
D. Louis Collins, Pierre Hellier, Pierre Meyer, Pi