Robotic Surgeon-Assistant System for Percutaneous Breast Therapies
Creators: Makhachev, Kirill
Publisher: name: University of Alberta Library
Year: 2024

<p>Breast cancer is one of the most common cancers diagnosed in women, with 1 in 8 women in Canada expected to develop it within their lifetimes. During the treatment of some forms of breast cancer, numerous procedures involve the insertion of percutaneous surgical instruments into the breast, such as biopsy, breast-preserving surgery known as lumpectomy, and more recently, low-dose-rate (LDR) brachytherapy. These therapies require a high degree of accuracy and highly skilled clinicians to be performed safely and successfully. For example, LDR brachytherapy involves the permanent implantation of radioactive seeds by needle into the volume of the excised tumor, known as the seroma, where the seeds must be placed precisely in accordance with the plan to obtain sufficient radiotherapy coverage. However, intraoperative visualization is unintuitive and cumbersome, as the insertion of the needle and maneuvering of the US probe for guidance must be performed concurrently by the same clinician. Additionally, the intraoperative imaging modality is a 2D ultrasound (US) probe, which provides limited situational awareness and is unintuitive to interpret. Such a workflow contributes to a high mental load and can result in surgical errors, especially for more novice clinicians. In this work, a robotic assistance system is presented that focuses on improving the working conditions and surgical outcomes of LDR brachytherapy, the subsystems of which can be generalized to other percutaneous breast therapies. The system alleviates mental duress by automating all non-invasive steps of an LDR brachytherapy procedure and enhances situational awareness by providing the clinician with a complementary digital twin of the surgical scene. This thesis details the design and experimental validation of this system.The thesis first describes the preoperative subsystems, which focus on the automatic localization and reconstruction of the seroma within the breast. These subsystems include a robotic US scan of the entire breast for image acquisition, leveraging deep learning to obtain automatic segmentations of the seroma, and using radial basis function interpolation to reconstruct the seroma virtually.Then, the thesis describes the intraoperative subsystems, which include robotic needle guide positioning, robotic US tracking of the needle tip within the tissue, and the additional visualization information presented in the virtual environment.Next, the feasibility study is described, which involves simulating an LDR brachytherapy procedure under the guidance of various visualization setups. The subjects evaluate their perceived workload with the NASA-TLX form, and their seed deposition accuracy and needle path length are used as quantitative metrics. The study&#39;s findings indicate that the system had a positive impact on the user&#39;s subjective experience, seed deposition accuracy, and needle insertion certainty, suggesting that alternative and additional visualizations of the surgical area could benefit surgical outcomes and patient safety in percutaneous breast therapies.The last portion of the thesis describes implemented system improvements. These include the process for obtaining the complete seroma reconstruction and augmented reality (AR) implementation with the HoloLens 2 headset.</p>