Introduction
Computer tomography (CT) angiography is widely accepted
as the gold standard for the examination of patients with
suspected pulmonary embolism (PE) [1]. The advantages of
CT are obvious: it is widely available, the method is fast, and it
is highly sensitive for the diagnosis of PE. In fact, in clinical
studies, the sensitivity of CT angiography is reported to range
between 53 % and 100 %, while its specificity ranges between
83 % and 100 % for diagnosing PE [2, 3]. Indeed, high
contrast within the pulmonary artery is essential to diagnose
the presence of PE with CT angiography. Moreover, insufficient
contrast enhancement in the pulmonary artery may