DOI
https://doi.org/10.25772/2XET-4B80
Defense Date
2018
Document Type
Dissertation
Degree Name
Doctor of Philosophy
Department
Medical Physics
First Advisor
Siyong Kim
Second Advisor
Woon-Hong Yeo
Third Advisor
Laura Padilla
Fourth Advisor
Taeho Kim
Abstract
One of the greatest challenges in achieving accurate positioning in head and neck radiotherapy is that the anatomy at and above the cervical spine does not act as a single, mechanically rigid body. Current immobilization techniques contain residual uncertainties that are especially present in the lower neck that cannot be reduced by setting up to any single landmark. The work presented describes the development of a radiotherapy friendly mostly-plastic 6D robotic platform for positioning independent landmarks, (i.e., allowing remote, independent positioning of the skull relative to landmarks in the thorax), including analysis of kinematics, stress, radiographic compatibility, trajectory planning, physical construction, and phantom measurements of correction accuracy. No major component of the system within the field of imaging or treatment had a measured attenuation value greater than 250 HU, showing compatibility with x-ray-based imaging techniques. Relative to arbitrary overall setup errors of the head (min = 1.1 mm, max = 5.2 mm vector error) the robotic platform corrected the position down to a residual overall error of 0.75 mm +/- 0.33 mm over 15 cases as measured with optical tracking. This device shows the potential for providing reductions to dose margins in head and neck therapy cases, while also reducing setup time and effort.
Rights
© Mark Ostyn
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
8-3-2018