Journal article
4DCT-based measurement of changes in pulmonary function following a course of radiation therapy
Medical physics (Lancaster), Vol.37(3), pp.1261-1272
03/2010
DOI: 10.1118/1.3312210
PMCID: PMC2842288
PMID: 20384264
Abstract
Purpose:
Radiation therapy (RT) for lung cancer is commonly limited to subtherapeutic doses due to unintended toxicity to normal lung tissue. Reducing the frequency of occurrence and magnitude of normal lung function loss may benefit from treatment plans that incorporate the regional lung and radiation dose information. In this article, the authors propose a method that quantitatively measures the regional changes in lung tissue function following a course of radiation therapy by using 4DCT and image registration techniques.
Methods:
4DCT data sets before and after RT from two subjects are used in this study. Nonlinear 3D image registration is applied to register an image acquired near end inspiration to an image acquired near end expiration to estimate the pulmonary function. The Jacobian of the image registration transformation, indicating local lung expansion or contraction, serves as an index of regional pulmonary function. Approximately 120 annotated vascular bifurcation points are used as landmarks to evaluate registration accuracy. The authors compare regional pulmonary function before and after RT to the planned radiation dose at different locations of the lung.
Results:
In all registration pairs, the average landmark distances after registration are on the order of 1 mm. The pulmonary function change as indicated by the Jacobian change ranges from −0.15 to 0.1 in the contralateral lung and −0.22 to 0.23 in the ipsilateral lung for subject A, and ranges from −0.4 to 0.39 in the contralateral lung and −0.25 to 0.5 in the ipsilateral lung for subject B. Both of the subjects show larger range of the increase in the pulmonary function in the ipsilateral lung than the contralateral lung. For lung tissue regions receiving a radiation dose larger than 24 Gy, a decrease in pulmonary function was observed. For regions receiving a radiation dose smaller than 24 Gy, either an increase or a decrease in pulmonary function was observed. The relationship between the pulmonary function change and the radiation dose varies at different locations.
Conclusions:
With the use of 4DCT and image registration techniques, the pulmonary function prior to and following a course of radiation therapy can be measured. In the preliminary application of this approach for two subjects, changes in pulmonary function were observed with a weak correlation between the dose and pulmonary function change. In certain sections of the lung, detected locally compromised pulmonary function may have resulted from radiation injury.
Details
- Title: Subtitle
- 4DCT-based measurement of changes in pulmonary function following a course of radiation therapy
- Creators
- Kai Ding - Department of Biomedical Engineering, The University of Iowa, Iowa City, Iowa 52242John E Bayouth - Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa 52242John M Buatti - Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa 52242Gary E Christensen - Department of Radiation Oncology, The University of Iowa, Iowa City, Iowa 52242 and Department of Electrical and Computer Engineering, The University of Iowa, Iowa City, Iowa 52242Joseph M Reinhardt - Department of Biomedical Engineering, The University of Iowa, Iowa City, Iowa 52242
- Resource Type
- Journal article
- Publication Details
- Medical physics (Lancaster), Vol.37(3), pp.1261-1272
- DOI
- 10.1118/1.3312210
- PMID
- 20384264
- PMCID
- PMC2842288
- ISSN
- 0094-2405
- eISSN
- 2473-4209
- Number of pages
- 12
- Grant note
- EB004126 / NIH HL079406 / NIH
- Language
- English
- Date published
- 03/2010
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Radiology; Electrical and Computer Engineering; Radiation Oncology; Radiation Research Laboratory; Neurosurgery; Otolaryngology
- Record Identifier
- 9984040439702771
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