Combined Assessment of Pulmonary Ventilation and Perfusion with Single-Energy Computed Tomography and Image Processing.
Acad Radiol
; 28(5): 636-646, 2021 05.
Article
in En
| MEDLINE
| ID: mdl-32534966
ABSTRACT
RATIONALE AND OBJECTIVES:
To establish a proof-of-principle for combined assessment of pulmonary ventilation and perfusion using single-energy computed tomography (CT) and image processing/analysis (denoted as single-energy CT ventilation/perfusion imaging). MATERIALS ANDMETHODS:
Breath-hold CT scans were acquired at end-expiration and end-inspiration before injection of iodinated contrast agents, and repeated at end-inspiration after contrast injection for 17 canines (8 normal and 9 diseased lung subjects). Ventilation images were calculated with deformable image registration to map the end-expiratory and end-inspiratory CT images and quantitative analysis for regional volume changes as surrogates for ventilation. Perfusion images were calculated by subtracting the end-inspiratory precontrast CT from the deformably registered end-inspiratory postcontrast CT, yielding a map of regional Hounsfield unit enhancement as a surrogate for perfusion. Ventilation-perfusion matching, spatial heterogeneity, and gravitationally directed gradients were compared between two groups using a Wilcoxon rank-sum test.RESULTS:
The normal group had significantly higher Dice similarity coefficients for spatial overlap of segmented functional volumes between ventilation and perfusion (median 0.40 vs. 0.33, pâ¯=â¯0.05), suggesting stronger ventilation-perfusion matching. The normal group also had greater Spearman's correlation coefficients based on 16 regions of interest (median 0.58 vs. 0.40, pâ¯=â¯0.09). The coefficients of variation were comparable (median, ventilation 0.71 vs. 0.91, pâ¯=â¯0.60; perfusion 0.63 vs. 0.75, pâ¯=â¯0.27). The linear regression slopes of gravitationally directed gradient were also comparable for ventilation (median, ventilation -0.26 vs. -0.18, pâ¯=â¯0.19; perfusion -0.17 vs. -0.06, pâ¯=â¯0.11).CONCLUSION:
These findings provide proof-of-principle for single-energy CT ventilation/perfusion imaging.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Tomography, X-Ray Computed
/
Pulmonary Ventilation
Limits:
Animals
Language:
En
Journal:
Acad Radiol
Journal subject:
RADIOLOGIA
Year:
2021
Document type:
Article
Affiliation country:
Japan