Helical computed tomography and magnet resonance imaging: diagnosis of pulmonary embolism in symptomatic patients.

Abstract

The diagnosis of pulmonary embolism is challenging because lung scanning is nondiagnostic in most patients and because pulmonary angiography is invasive. Advancements in computed tomography and magnetic resonance imaging have enabled visualization of pulmonary emboli. Studies using each of these modalities have demonstrated high sensitivity for lobar and segmental emboli and lower sensitivity for subsegmental emboli. A recent study of a management approach using spiral computed tomography combined with testing for deep vein thrombosis using compression ultrasonography was found to have high clinical validity. A number of different magnetic resonance imaging techniques have been used to identify pulmonary emboli, and no single technique has been shown to be superior. Further studies are needed to delineate the role of magnetic resonance imaging in the management of patients with suspected pulmonary embolism.