@article{Kirsten van Langevelde_Alexandr Šrámek_Patrice W.J. Vincken_Jan-Kees van Rooden_Frits R. Rosendaal_Suzanne C. Cannegieter_2013, place={Pavia, Italy}, title={Finding the origin of pulmonary emboli with a total-body magnetic resonance direct thrombus imaging technique}, volume={98}, url={https://haematologica.org/article/view/6570}, DOI={10.3324/haematol.2012.069195}, abstractNote={Pulmonary embolism is considered to originate from embolization of a deep-vein thrombosis, resulting in two manifestations of one disease: venous thrombosis. However, in up to 50% of patients with pulmonary embolism no deep-vein thrombosis is found with ultrasonography. An explanation for this low proportion is currently lacking. Other imaging modalities may increase the yield of detection of deep-vein thrombosis in the calf or in the abdominal region. Alternatively, not all pulmonary emboli may originate from deep-vein thromboses in the extremities. We searched for the origin of pulmonary emboli, by performing total-body magnetic resonance imaging-scans to visualize thrombi. Ninety-nine patients with a first pulmonary embolism confirmed by computed tomography underwent a magnetic resonance direct thrombus imaging-scan, a validated technique using endogenous contrast. Additionally, acquired and genetic risk factors were assessed. No thrombus was found in 55 patients, whereas a thrombus was identified in 44 patients. The commonest thrombus location was the lower leg; 12 patients had isolated calf vein thrombosis and five had isolated superficial vein thrombosis. A peripheral thrombus was found by magnetic resonance imaging in less than half of patients with pulmonary embolism. We propose several hypotheses to explain the absence of thrombi, such as a cardiac thrombus origin or embolization of the whole deep-vein thrombus. The possibility that pulmonary embolism arises <em>de novo</em&gt; in the lungs, due to local inflammation-driven coagulation, needs to be considered.}, number={2}, journal={Haematologica}, author={Kirsten van Langevelde and Alexandr Šrámek and Patrice W.J. Vincken and Jan-Kees van Rooden and Frits R. Rosendaal and Suzanne C. Cannegieter}, year={2013}, month={Feb.}, pages={309-315} }