A minimally invasive biomechatronic approach for breast cancer surgery

This paper presents a novel mechatronic approach for minimally invasive excision of breast tumors along with a pre-defined margin tissue, by extending directional vacuum-assisted biopsy (DVAB) technique. Means of overcoming the limitations of mammotome biopsy probe (by J&J) while adopting it for complete removal of tumor and margin area, which may lead to unpredictable removal of tissue from ill-defined location, are presented. A dual arm robotic system in a hybrid configuration, whereby imaging probe and excision needle can be independently maneuvered, is designed using a modular approach. Two systematic methods for tissue excision viz. the progressive removal and oscillatory removal are proposed and implemented for multiple resections through the target tissue region and ensuring complete removal of the tumor. Collapsing of the tissue after each removal has been taken into consideration while developing the systematic method of tissue removal. System GUI is developed to help the end-users/clinicians for image guidance, target and margin demarcation, on-line update on volume estimation, positioning and controlling the manipulator. A representative number of tissue phantoms were tested to validate the feasibility of the system and proposed concept. The accuracy and repeatability of our present system was measured as ± 0.5 mm and within ± 0.1 mm, respectively.