[The radiological evaluation of the abnormal thymus and its frequency in myasthenia gravis (author's transl)].

The radiological evaluation of the thymus is discussed and the results of 159 pneumomediastinums are described. Amongst these patients, 28.5% had a persistent thymus, 41.1% showed partial involution of the thymus, 22.5% showed total involution and in 7.9% a thymoma was found. Comparison of patients with myasthenia gravis with a group suffering from autoimmune diseases showed a similar incidence of abnormal thymuses. The value of radiology in assessing the need for thymectomy as a treatment is stressed.