Perfusion defects in pulmonary perfusion iodine maps: causes and semiology

to describe the usefulness of dual-energy CT for obtaining pulmonary perfusion maps to provide morphological and functional information in patients with pulmonary embolisms. To review the semiology of perfusion defects due to pulmonary embolism so they can be differentiated from perfusion defects due to other causes: alterations outside the range used in the iodine map caused by other diseases of the lung parenchyma or artifacts.

CT angiography of the pulmonary arteries is the technique of choice for the diagnosis of pulmonary embolisms. New dual-energy CT scanners are useful for detecting perfusion defects secondary to complete or partial obstruction of pulmonary arteries and is most useful for detecting pulmonary embolisms in subsegmental branches.