Conference Paper

Computer-Assisted Navigation on the Arrested Heart During CABG Surgery.

Conference: Bildverarbeitung für die Medizin 2009: Algorithmen - Systeme - Anwendungen, Proceedings des Workshops vom 22. bis 25. März 2009 in Heidelberg
Source: DBLP
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    ABSTRACT: Coronary artery bypass grafting (CABG) is the most commonly performed type of open heart surgery. For an ef-fective revascularisation procedure, the identification of the optimal anastomotic site is of utmost importance. To assist the surgeon in this matter, a surgical navigation system for the open heart is desirable. During surgery, its purpose is to provide a patient-specific map of the coronaries in which the current position of a surgical pointing device (Cardio-Pointer) is visualised. To enable navigation on the heart surface, registration of pre-and intraop-erative modalities is required. This work focusses on an appropriate method for registration of the 3D map of the coronaries extracted from preoperative MSCT (multi-slice computed tomography) data with optical tracking data recorded intraoperatively at the ischaemic heart. The registration algorithm is based on mutually shared anatomical point landmarks and vessel paths on the surface of the heart. Depending on the number and type of landmarks visible both in the MSCT images and during surgery on the surface of the heart itself, the method consists of up to four successive steps. This includes a rigid, coarse registration followed by an enhanced weighted ICP algorithm, corrections for the effects of muscle relaxation and torsion of the non-beating heart, and if suitable the generation of additional landmark points by means of vessel length calculations. The registration process has been validated retrospectively on real patient data sets recorded during CABG surgery.
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    ABSTRACT: Since the discovery of X-rays, medical imaging has played a major role in the guidance of surgical procedures. While medical imaging began with simple X-ray plates to indicate the presence of foreign objects within the human body, the advent of the computer has been a major factor in the recent development of this field. Imaging techniques have grown greatly in their sophistication and can now provide the surgeon with high quality three-dimensional images depicting not only the normal anatomy and pathology, but also vascularity and function. One key factor in the advances in Image-Guided Surgery (IGS) is the ability not only to register images derived from the various imaging modalities amongst themselves, but also to register them to the patient. The other crucial aspect of IGS is the ability to track instruments in real time during the procedure, and to portray them as part of a realistic model of the operative volume. Stereoscopic and virtual-reality techniques can usefully enhance the visualization process. IGS nevertheless relies heavily on the assumption that the images acquired prior to surgery, and upon which the surgical guidance is based, accurately represent the morphology of the tissue during the surgical procedure. In many instances this assumption is invalid, and intra-operative real-time imaging, using interventional MRI, Ultrasound, and electrophysiological recordings are often employed to overcome this limitation. Although now in extensive clinical use, IGS is often currently perceived as an intrusion into the operating room. It must evolve towards becoming a routine surgical tool, but this will only happen if natural and intuitive human interfaces are developed for these systems.
    Computer Methods in Biomechanics and Biomedical Engineering 02/2000; 4(1):27-57. DOI:10.1080/10255840008907997 · 1.79 Impact Factor
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    ABSTRACT: The aim of this work is to quantify the errors introduced at different levels of applying results planned using a computer integrated surgery system in the operating room, and to make use of these errors to adapt the transfer and rethink the planning. In particular, we address the registration between preoperative imaging and the intraoperative patient model, as well as between the patient and the robot. Two different registration methods are used and their accuracies compared. Moreover, augmented reality trials are conducted to assess the difficulty of adapting preoperative data to intraoperative models in order to deliver useful information to the surgeon during the intervention. The experimental work in this paper is conducted on a dog for a coronary bypass intervention using the da Vinci™ surgical system.
    The International Journal of Robotics Research 04/2004; 23:539-548. DOI:10.1177/0278364904042205 · 2.50 Impact Factor