[Magnetic resonance imaging in the diagnosis of myxedematous pericardial effusions].

Two cases of myxedematous pericardial effusions studied by magnetic resonance imaging (MRI) are reported. After a reminder of the place of pericardial involvement in this disease, the advantage of MRI which provides original semiologic factors on the analysis of topographic extension and on the approach of the cellular characteristics of the effusion, is presented. Concerning the latter, difficulties of interpretation and current imprecisions are discussed but we will especially remember the advantage of this recent technique in the diagnosis of an effusion, even moderate, in hypothyroidism, mainly in patients with poor sonographic response.