Date of Award
Master of Engineering Science
Dr. Terry Peters
Minimally invasive surgery is becoming popular for a number of interventions. Use of robotic surgical systems in coronary artery bypass intervention offers many benefits to patients, but is however limited by remaining challenges in port placement. Choosing the entry ports for the robotic tools has a large impact on the outcome of the surgery, and can be assisted by pre-operative planning and intra-operative guidance techniques. In this thesis, pre-operative 3D computed tomography (CT) imaging is used to plan minimally invasive robotic coronary artery bypass (MIRCAB) surgery. From a patient database, port placement optimization routines are implemented and validated. Computed port placement configurations approximated past expert chosen configurations with an error of 13.7 ±5.1 mm. Following optimization, statistical classification was used to assess patient candidacy for MIRCAB. Various pattern recognition techniques were used to predict MIRCAB success, and could be used in the future to reduce conversion rates to conventional open-chest surgery. Gaussian, Parzen window, and nearest neighbour classifiers all proved able to detect ‘candidate’ and ‘non-candidate’ MIRCAB patients. Intra-operative registration and laser projection of port placements was validated on a phantom and then evaluated in four patient cases. An image-guided laser projection system was developed to map port placement plans from pre-operative 3D images. Port placement mappings on the phantom setup were accurate with an error of 2.4 ± 0.4 mm. In the patient cases, projections remained within 1 cm of computed port positions. Misregistered port placement mappings in human trials were due mainly to the rigid-body registration assumption and can be improved by non-rigid techniques. Overall, this work presents an integrated approach for: 1) pre-operative port placement planning and classification of incoming MIRCAB patients; and 2) intra-operative guidance of port placement. Effective translation of these techniques to the clinic will enable MIRCAB as a more efficacious and accessible procedure.
Marmurek, Jonathan, "Image-guided port placement for minimally invasive cardiac surgery" (2009). Digitized Theses. 4285.