4-Dimensional computed tomography-based ventilation and compliance images for quantification of radiation-induced changes in pulmonary function.
J Med Imaging Radiat Oncol
; 63(3): 370-377, 2019 Jun.
Article
em En
| MEDLINE
| ID: mdl-30932346
ABSTRACT
INTRODUCTION:
4-Dimensional computed tomography (4DCT)-based ventilation imaging is a promising technique for evaluating pulmonary function, but lung elasticity and mechanics are usually not part of the ventilation image analysis. In this study we demonstrate a 4DCT-based imaging technique that can be used to calculate regional lung compliance changes after radiotherapy (RT).METHODS:
Six lung cancer patients were included in this study. Four of the patients had 4DCT images acquired pre-RT, 3 and 9 months post-RT. Ventilation and compliance were calculated from the deformable image registration (DIR) of 4DCTs, performed from the end-inhale to the end-exhale breathing phase. Regional compliance was defined as the ratio of volumetric variation and associated stress in each voxel, representing lung elasticity and computed using a FEM-based framework. Ventilation, compliance and CT density were calculated for all pre-RT and post-RT 4DCTs and evaluation metrics were computed.RESULTS:
Average CT density changes were 13.6 ± 11.4HU after 3 months and 26.9 ± 15.8HU after 9 months. Ventilation was reduced at 3 months, but improved at 9 months in regions with dose ≥ 35 Gy, encompassing about 10% of the lung volume; compliance was reduced at both time-points. Radiation dose ≥ 35 Gy caused major change in lung density and ventilation, which was higher than that previously reported in the literature (i.e. 24 Gy).CONCLUSION:
Lung tissue response is diverse with respect to CT density, ventilation and compliance. Combination of ventilation and compliance with CT density could be beneficial for understanding radiation-induced lung damage and consequently could help develop improved treatment protocols for lung cancer patients.Palavras-chave
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Base de dados:
MEDLINE
Assunto principal:
Complacência Pulmonar
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Carcinoma Pulmonar de Células não Pequenas
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Ventilação Pulmonar
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Tomografia Computadorizada Quadridimensional
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Neoplasias Pulmonares
Tipo de estudo:
Guideline
Limite:
Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article