New imaging techniques for the diagnosis of pulmonary embolism

Pulmonary embolism (PE) remains a common cause of illness and death. Appropriate therapy requires timely diagnosis, but the currently available noninvasive diagnostic methods lack adequate sensitivity and specificity. In particular the vast majority of ventilation-perfusion scans are unable to confirm or reliably exclude PE, cannot differentiate between acute and chronic PE, and provide no clues about possible alternate explanations of presenting symptoms (even if PE can be excluded). Although the precise role of these scans in the diagnosis of PE remains to be clarified, recent advances appear to ensure a place for magnetic resonance imaging and helical computed tomography in the diagnostic evaluation of PE in the near future.