Document Type

Dissertation

Date of Degree

Spring 2013

Degree Name

PhD (Doctor of Philosophy)

Degree In

Biomedical Engineering

First Advisor

Joseph M. Reinhardt

Second Advisor

John E. Bayouth

Abstract

Current radiation therapy (RT) planning for limiting lung toxicity is based on a uniform lung function with little consideration to the spatial and temporal pattern of lung function. Establishment of relationships between radiation dose and changes in pulmonary function can help predict and reduce the RT-induced pulmonary toxicity. Baseline measurement uncertainty of pulmonary function across scans needs to be assessed, and there is a great interest to compensate the pulmonary function for respiratory effort variations.

Respiratory-gated 4DCT imaging and image registration can be used to estimate the regional lung volume change by a transformation-based ventilation metric which is computed directly from the deformation field, or a intensity-based metric which is based on CT density change in the registered image pair. In this thesis, we have evaluated the reproducibility of regional pulmonary function measures using two repeated 4D image acquisitions taken within a short time interval for both transformation-based and intensity-based metrics. Furthermore, we have proposed and compared normalization schemes that correct ventilation images for variations in respiratory effort and assess the reproducibility improvement after effort correction.

The major contributions of this thesis include: 1) develop and validate a process for establishing measurement reproducibility in 4DCT-based ventilation, 2) evaluate reproducibility of the transformation-based ventilation measurement, 3) evaluate reproducibility of the intensity-based ventilation measurement, 4) develop and compare different ventilation normalization methods to correct for respiratory effort variation across scans.

Keywords

4DCT, image registration, lung, pulmonary function, reproducibility, ventilation

Pages

xv, 196 pages

Bibliography

Includes bibliographical references (pages 185-196).

Comments

This thesis has been optimized for improved web viewing. If you require the original version, contact the University Archives at the University of Iowa: http://www.lib.uiowa.edu/sc/contact/.

Copyright

Copyright 2013 Kaifang Du

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