Computed tomography and magnetic resonance imaging in the diagnosis of pulmonary thromboembolic disease.

In selected cases CT and MRI may be useful for the evaluation of patients suspected of having central pulmonary emboli. In stable patients MRI appears to be superior to CT because no iodinated contrast medium is required. In evaluating critically ill patients CT is better because of its superior resolution, ability to assess changes in the lung parenchyma, and ease of patient monitoring.