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"This thesis presents a single-slice based fast stereotactic registration and tracking technique along with a corresponding modular system for guiding robotic mechanism or interventional instrument to perform needle-based interventions under live MRI guidance. The system can provide tracking of full 6 degree-of-freedom (DOF) in stereotactic interventional surgery based upon a single, rapidly acquired cross-sectional image. The whole system is constructed with a modular data transmission software framework and mechanical structure so that it supports remote supervision and manipulation between a 3D Matlab tracking user interface (UI) and an existing MRI robot controller by using the OpenIGTLink network communication protocol. It provides better closed-loop control by implementing a feedback output interface to the MRI-guided robot. A new compact fiducial frame design is presented, and the fiducial is wrapped with a passive resonant coil. The coil resonates at the Larmor frequency for 3T MRI to enhance signal strength and enable for rapid imaging. The fiducial can be attached near the distal end of the robot and coaxially with a needle so as to visualize target tissue and track the surgical tool synchronously. The MRI-compatible design of fiducial frame, robust tracking algorithm and modular interface allow this tracking system to be conveniently used on different robots or devices and in different size of MRI bores. Several iterations of the tracking fiducial and passive resonant coils were constructed and evaluated in a Phillips Achieva 3T MRI. To assess accuracy and robustness of the tracking algorithm, 25 groups of images with different poses were successively scanned along specific sequence in and MRI experiment. The translational RMS error along depth is 0.271mm with standard deviation of 0.277mm for totally 100 samples. The overall angular RMS error is less than 0.426 degree with standard deviation of 0.526 degree for totally 150 samples. The passive resonant coils were shown to significantly increase signal intensity in the fiducial relative to the surroundings and provide for rapid imaging with low flip angles. "

This thesis proposes a multidirectional methodological framework for a comprehensive ergonomic analysis and modelling of workflow for multi-modal vascular image-guided procedures (IGPs). Two approaches are employed to analyse the workflow: Discrete Event Simulation (DES) and purpose-oriented physical models. In contrast to previous studies, the proposed methodology looks in detail the actions carried out within the intervention rooms and the clinical experience during the procedures with three main objectives: to provide a deeper understanding of vascular procedures, to predict the impact of protocol modifications and to offer a framework to develop new image-guided protocols for the alternative use of Magnetic Resonance (MR) imaging in comparison with X-Ray Digital Subtraction Angiography (DSA). The methodological framework includes an assessment of commercial simulation software packages to evaluate their fitness to the specific requirements of this research. The novel methodology is applied to several cases studies of common vascular IGPs. In addition, a case of MR – guided focused ultrasound intervention demonstrates how it is possible to extend the framework to study non-vascular IGPs. The multi-disciplinary methodological framework described opens a new way to understand IGPs that could be used in prospective applications such as medical education and medical devices regulations.

This formative evaluation focuses on feedback regarding a self-guided educational intervention for those at the crossroads of divorce. Entitled Should I Keep Trying to Work It Out? A Guidebook for Individuals and Couples at the Crossroads of Divorce (And Before), this Guidebook aims to help individuals minimize possible ambiguity in the decision-making process surrounding divorce. Fifty-three participants were recruited through divorce orientation education classes to provide formative feedback via brief phone surveys. Eighteen of these provided in-depth interviews for additional feedback. Though the participants in this study were largely past the crossroads of divorce, most agreed or strongly agreed that the Guidebook was helpful (61%), trustworthy (88%), helped them change some of their attitudes about divorce (67%), and helped them be more prepared for the divorce (81%). Additionally, 64% reported feeling more confident about their decision to divorce, including three noteworthy cases that cited domestic violence as their reason for divorce. Overall, this Guidebook appears to be useful to those who are contemplating divorce. Options for improving the Guidebook and introducing it earlier in the decision-making process are discussed.

Percutaneous needle placement, a minimally invasive procedure performed dozens of millions in the U.S. each year, relies on dedicated skill and long-term training due to difficult control of needle trajectory inside tissue and mental registration of images to locations inside the patient. Inaccurate needle placement may miss cancer tumors during diagnosis or eradicate healthy tissue during therapy. MRI provides ideal procedure guidance with the merit of excellent soft tissue contrast and volumetric imaging for high spatial resolution visualization of targets and surgical tool. However, manual insertion in the bore of an MRI scanner has awkward ergonomics due to difficult access to the patient, making both training and intervention even harder. To overcome the challenges related to MRI electromagnetic compatibility and mechanical constraints of the confined close-bore, a modular networked robotic system utilizing piezoelectric actuation for fully actuated prostate biopsy and brachytherapy is developed and evaluated with accuracy study. To enhance manipulation dexterity, two kinds of steerable continuum needle robots are developed. The asymmetric tip needle robot performs needle rotation and translation control to minimize tissue deformation, and increase steering dexterity to compensate placement error under continuous MRI guidance. The MRI-guided concentric tube robot is deployed to access delicate surgical sites that are traditionally inaccessible by straight and rigid surgical tools without relying on tissue reaction force. The master-slave teleoperation system with hybrid actuation is the first of its kind for prostate intervention with force feedback. The teleoperation controller provides the feel and functionality of manual needle insertion. Fabry- Perot interferometer based fiber optic force sensor is developed for the slave manipulator to measure needle insertion force and render proprioception feedback during teleoperation.