Differential Diagnosis Of Pulmonary Hypertension With Dual Energy CT (DECT)
Chronic thromboembolic disease (CTEPH) is one of many causes of pulmonary hypertension. For this there is a new drug and interventional therapies. Diagnosis is made by detection of segmental defects of the lung perfusion. Previous standard method is the perfusion ventilation scintigraphy, which is performed in addition to a pulmonary CT angiography. The Dual Energy CT (DECT), which is used at the Lung Clinic Berlin for two years to diagnose CTEPH combines the CT angiography and lung perfusion in one examination.
In a DECT the lung is irradiated in about five seconds simultaneously with X-rays of two different energies. In addition to the morphological image of the pulmonary artery and the pulmonary parenchyma the distribution of the contrast agent is shown in the lung parenchyma (lung perfusion). Advantages over a scintigraphy are the higher spatial resolution of a CT and being able to be more precise with anatomical mapping of outages of perfusions of the lung structure. Especially for patients with emphysema and inhomogeneous lung perfusion, the DECT can be useful by detecting additional perfusion defects, caused by chronic thromboembolisms. Experience shows that with scintigraphy negative results the DECT may still show perfusion defects in individual cases. The DECT provides additional diagnostic information, which are required for adequate treatment of pulmonary hypertension.
Since 2013, the Lung Clinic Berlin, as the only German Lung Clinic, uses a DECT-enabled high-end CT scanner. All examination results are interdisciplinary discussed with the attending pulmonologists. Outpatient DECT is possible through our PAH ambulance.
PD Dr. med. Dag Wormanns, is chief physician at the Radiological Institute of Lung Clinic Berlin.
Picture: Lung image in Pulmonary Hypertension CT