Signature-Based Algorithm for Improved Needle Localization in Ultrasound Images: a Feasibility Study

Ultrasound imaging is commonly used to guide needle insertion procedures, such as biopsies and anesthesia. In such procedures, the needle can be poorly visualized, making it difficult to determine the needle trajectory. A novel needle detection algorithm is introduced based on the unique needle reflection pattern of circular ultrasound waves. The proposed algorithm was evaluated by locating a needle placed in an agar phantom. Circular waves were created using a 5 MHz, curvilinear transducer array. The coordinates of the needle axis were estimated when the angle between the needle and the transducer central axis was varied between 50 degrees and 90 degrees. The differences between the radial and azimuth coordinates of the needle estimated using the proposed algorithm and those calculated using computed tomography scan of the phantom were within 0.1 to 0.5 mm and 0.0 degrees to 3.1 degrees, respectively.