In breast cancer screening, suspicious lesions may be found that need to be checked for malignancy. A biopsy is the only diagnostic procedure for accurate histological confirmation, usually under ultrasound guidance. When sonographic placement is not allowed, a Magnetic Resonance Imaging-guided biopsy procedure is necessary.
The lack of real-time imaging information and the deformations of the breast make it difficult to bring the needle precisely towards the lesion detected in pre-interventional MR images: the current manual MRI-guided biopsy procedure is inaccurate and would benefit from a technique that allows real-time tracking and visualization of the lesion during needle insertion.
The MRI and Ultrasound Robotic Assisted Biopsy (MURAB) project has the ambition of revolutionizing the way breast cancer is researched for patient and improve biopsy of lesions that are only visible on MRI. The main focus of the project is the development of software architecture to combine the high precision of MRI scanning with stereo vision localization in the physical space to estimate the current target location and achieve an accurate needle placement and tissue extraction. In particular, the real-time tumour location is computed by optically tracking multimodality-visible markers attached on the skin of the patient. On MRI, the markers and the lesions which need to be biopted are precisely localized and then segmented in software. Subsequently, a tracking system is exploited to evaluate the current position of fiducials and access surface deformations. Data acquired in the preoperative phase are combined with intraoperative data to compute and periodically update the current tumour location and plan the precise needle path for a robotically steered biopsy system. The last objective involved in the assignment is the control of a hand-mounted motorized needle angulation tool, which is able to carry out the biopsy procedure in the computed target location.
The performances of the implemented architecture are evaluated through phantom experiments.