Purpose
INTRODUCTION:
Pulmonary CT angiography (CTA) is the gold standard techniquefor the diagnosis of acute pulmonary embolism (APE).
Dual Energy CT Angyography (DECTA) with dual source technique allows to perform iodine maps of thelung parenquima.
These iodine maps are rutinely used to detect perfusion defectsand to verify the extension of vascular impairmentinAPE patients.
This toolmakesthe diagnose ofsubsegmentary endoluminal clots easier ,sometimes missed in conventional angiographic images,
by detecting small perfusion defects.
Fig.
1
While conventional pulmonary CTAprovides only morphologic information and does not allow the direct...
Methods and Materials
50 patients who underwent DECTA with clinical suspicion of APE were retrospectively selected:
25 healthy subjects without APE or pulmonary pathology that could interfere with iodine maps.
25 subjects with any kind of APE (oclusive or non oclusive thrombus),
without other concomitant lung disease
36 women,
14 men; mean age: 77 y.o.
The aplication “Lung PBV” and the tool "Lung Isolation" of Siemens softwareCT was used to measure: Fig.2 Fig.3 Fig.4
average enhancement (Hounsfield Units)of total,
left and right lung parenchyma.
relative enhancement of lung...
Results
Average enhancement for total lung parenchyma was 30,64 ± 5,83 HU for healthy pacientes (HP) and 25,60 ± 10,87 HU for patientes with APE (APEP).
Relative enhacement was 84,68 ± 24,25 (HP) and 78,88 ± 24,29 (APEP).
Statistically significant differences were found with average lung enhancement (p<0.003).
However,
there were no differences with relative enhancement (p=0,264) between both groups.
Fig.
5
Conclusion
Iodine lung perfusion maps show different average parenchymal enhancement between healthy subjects and patients with APE; which could be used to improve accuracy diagnosis and predict severity ofAPEwith further investigations.
References
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Dual-Energy CT for the Assessment of Contrast Material Distribution in the Pulmonary Parenchyma.
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