The Age of CT Pulmonary Angiography

Abstract

With the introduction of multi detector-row CT (MDCT), computed tomography (CT) has been firmly established as the de facto first line test for imaging patients with suspected pulmonary embolism (PE). However, remaining concerns regarding CT's accuracy for diagnosis of isolated peripheral emboli have prevented the unanimous acceptance of this test as the standard of reference for imaging PE. Consequently, many patients with a chest CT scan negative for PE undergo additional testing for a definitive rule-out of PE, increasing radiation burden, risk of complications, and health care cost. After a decade of uncertainty, there is now conclusive evidence that computed tomography (CT), if positive, provides reliable confirmation of the presence of PE and, more importantly, if negative effectively rules out clinically significant PE. Current endeavors to streamline and facilitate workflow for CT diagnosis of PE will further improve the acceptance, utility, and importance of this test. Thus, rather than seeking further confirmation for the accuracy of CT for PE diagnosis, future efforts ought to be directed at harnessing the unique strengths of this test. Examples include improvements in workflow, CT derivation of right ventricular function parameters for triage and prognostication of patients with acute PE, and the comprehensive assessment of patients with acute chest pain for PE, coronary disease, aortic disease, and pulmonary disease by means of a single, contrast enhanced, ECG-synchronized CT scan. At the same time, efforts must be directed at refining clinical pathways to ensure appropriate use and avoid overutilization of this test.

Evaluation of right ventricular dysfunction and prediction of clinical outcomes in acute pulmonary embolism by chest computed tomography: comparisons with echocardiography

“…Contrast-enhanced chest computed tomography (CT) has become the first-line imaging test for patients with suspected pulmonary embolism [3,6,7]. Sometimes, CT is more rapidly accessible in emergency settings, and is more widely available than echocardiography.…”

Image Quality and Radiation Exposure at Pulmonary CT Angiography with 100- or 120-kVp Protocol: Prospective Randomized Study

“…Pulmonary CT angiography has been demonstrated to result in lower radiation exposure than conventional angiography (9,10). However, CT is the most important source of radiation exposure for the general population and is of special concern with respect to thin-section acquisition of extensive anatomic volumes, which have become feasible with multidetector CT (11).…”

High-pitch Dual-source Computed Tomography Pulmonary Angiography in Freely Breathing Patients

“…[1][2][3][4] In conventional single-source CT systems, the table feed is limited to a pitch of 1.5 to avoid gaps in the raw data set. This means that, even with modern multidetector-row CT (MDCT), a breath-hold period of a couple of seconds is required for motion-free imaging of the pulmonary vessels and lung parenchyma.…”