Role of Computed Tomography and Magnetic Resonance Imaging for Deep Venous Thrombosis and Pulmonary Embolism

Abstract

Abstract-During the 1990s, computed tomography (CT) and magnetic resonance (MR) imaging underwent extensive technological advancement and expanded clinical use in patients with venous thromboembolic disease, particularly with regard to evaluation of the pulmonary vasculature. In many institutions, helical (spiral) CT pulmonary angiography has become the initial imaging study of choice to evaluate patients with suspected pulmonary embolism, supplanting ventilation/perfusion scintigraphy. In addition, CT venography of the pelvis and lower extremities is often incorporated into the CT angiography protocol to identify or exclude concurrent deep venous thrombosis. MR pulmonary angiography and MR venography are second-line diagnostic tools because of their higher cost, limited availability, and other logistical constraints. As the technology improves and becomes more widely available, MR imaging may play a greater role in the evaluation of patients with venous thromboembolic disease. Key Words: thrombosis Ⅲ pulmonary heart disease Ⅲ imaging Ⅲ MRI D uring the 1990s, technological advances in computed tomography (CT) and magnetic resonance (MR) imaging made these techniques applicable to the diagnosis of venous thromboembolic disease, particularly for the pulmonary vasculature in patients with suspected pulmonary embolism (PE). At the opening of the third millennium, in many institutions, helical (spiral) CT pulmonary angiography (CTPA) has become the initial imaging study of choice for evaluating patients with suspected PE, supplanting ventilation/perfusion (V/Q) scintigraphy by reducing indeterminate examinations. 1-4 CT venography (CTV) of the pelvic and lower extremity veins after CTPA of the pulmonary arteries has been advocated by some as an adjunct to helical CT for detection of concurrent deep venous thrombosis (DVT) using a single imaging technique for detection of venous thromboembolic disease.Although MR imaging produces high tissue contrast without ionizing radiation, currently, this technique is less popular than CT for evaluation of acute venous thromboembolism (VTE) because of technical limitations, higher costs, limited availability, and other logistical considerations. As technology improves, however, MR pulmonary angiography (MRPA) and MR venography (MRV) may play a greater role in the evaluation of patients with venous thromboembolic disease.This article reviews applications of CT and MR imaging in the clinical evaluation of patients with suspected venous thromboembolic disease. CT Pulmonary AngiographyCTPA has gained acceptance as a first-line imaging study in cases of suspected acute PE, replacing traditional V/Q scintigraphy at many institutions. In general, V/Q scanning is reserved for patients in whom motion artifact or poor right heart function limit the quality of CT examination and those with contraindications to intravenous radiographic contrast.After contrast administration, CTPA provides visualization of the pulmonary arterial system in the axial plane, and multiplanar and three-dimensional...

Advanced imaging in acute and chronic deep vein thrombosis

“…CT pulmonary angiography (CTPA) has become initial modality of choice in evaluating patients with suspected PE (32). CTV of the pelvic and lower extremity veins after CTPA can be used for concurrent DVT detection.…”

Case report: Optimizing intraoperative detection of pulmonary embolism using contrast-enhanced echocardiography

“…Limitations on spatial resolution, however, make evaluation of segmental and subsegmental PE difficult. 19 In cases of massive PE, the sensitivity and specificity of TEE without contrast agents were reported to be as high as 80-97% and 84-100%, respectively, and virtually comparable with the diagnostic accuracy of CT scanning. 4 Intraoperatively, however, the sensitivity of TEE to detect PE in patients undergoing emergent pulmonary embolectomy has been reported to be only 46%, while the sensitivity for direct visualization of thromboemboli at any specific location was even lower at 26%.…”

Diagnosis and Treatment of Lower Extremity Deep Vein Thrombosis: Korean Practice Guidelines

“…(3) CT venography: Although ultrasonography is widely used for the diagnosis of DVT, CT venography has recently been documented as a rapid and available alternative to ultrasonography for lower extremity DVT, with sensitivity and specificity of 89%-100% and 94%-100%, respectively [87][88][89][90][91][92]. CT venography typically involves injection of contrast media into an arm vein, followed by multi-detector CT imaging timed to coincide with opacification of the deep veins of the legs to allow assessment of these veins for thrombus.…”