Robotic System for Biopsy and Therapy of Breast Lesions in a High-Field Whole-Body Magnetic Resonance Tomography Unit

摘要

RATIONALE AND OBJECTIVES: With magnetic resonance mammography, significant progress has been achieved in the diagnosis of small breast cancers. However, biopsy and therapy of suspicious lesions must take place at a later time. Diagnosis and simultaneous biopsy and therapy in one single examination would considerably reduce costs, strain on the patient, and side effects. METHODS: ROBITOM (Robotic system for biopsy and interventional therapy of mammary lesions) is used to approach a lesion found in the breast in an image-controlled manner under a high magnetic field (eg, 1.5 T). The robotic system works in the direct vicinity of the isocenter of a magnet and consists of a trocar, coaxial sleeve, biopsy needle, laser applicator, and a control and driving unit. It contains a rack, a driving unit along the three coaxes of space, and a gripping unit for instruments or biopsy sample removal. The system has six degrees of freedom. RESULTS: In vitro experiments in pig liver including eight targets (vitamin E capsules, 4 mm in diameter) were performed. All eight capsules were hit precisely by the robotic biopsy system. The procedure was performed directly in the isocenter of a 1.5-T whole-body scanner. CONCLUSIONS: The system allows the coordinates of a lesion in the breast to be approached in a high magnetic field without shifting the patient. A combination of imaging with biopsy and subsequent therapy (eg, laser therapy or cryotherapy) seems to be feasible in the future.