Dual Source CT Lung Perfused Blood Volume imaging with Dual Energy

SOMATOM Definition Dual Energy Scanning

Ralf W. Bauer, J. Matthias Kerl, Thomas J. Vogl
Department of Diagnostic and Interventional Radiology/Johann Wolfgang Goethe University Frankfurt, Germany
 |  2008-06-10


A 61 year old woman with known advanced lung cancer presented to the emergency department with sudden onset of shortness of breath, chest pain, and dropped arterial O2-saturation. She was referred to pulmonary CT angiography for clinically suspected pulmonary embolism.


Pulmonary CTA was performed utilizing the Dual Energy Lung PBV protocol. Pulmonary embolism could be ruled out by CTA. Instead, a large lymph node mass in the upper mediastinum was identified. This mass caused encasing of the superior vena cava, the right pulmonary artery, and major obstruction of the right upper lobe branch. Analysis of the iodine distribution map with Dual Energy revealed a huge perfusion defect of the whole upper lobe of the right lung, explaining the woman´s symptoms. The patient was then immediately referred to the Department of Radiation Oncology of our hospital for emergency irradiation.


Analysis of pulmonary iodine distribution with Dual Energy can provide important information not only about the significance of intravascular obstruction such as pulmonary embolism but about vascular obstruction in general. The influence of vascular obstruction identified with the conventional morphological information of CT on hemodynamics can be assessed using different information of the same scan. Thus, Dual Energy CT can provide both morphological and functional information within one scan.

Examination Protocol

SOMATOM Definition
Scan area
Scan length 180 mm
Scan time 5 s
Scan direction Caudo-cranial
140/80 kV
Effective mAs
28/176 eff. mAs
Rotation time
0.33 s
Slice collimation
14 x 1.2 mm
Reconstructed slice thickness
1.5 mm
Increment 1 mm

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