The authors demonstrate the observations of four patients with radiation myelopathy, localized in three instances in the cervical spinal cord - the basic disease was pleomorphic adenocarcinoma of the parotid gland, malignant immunoblastic lymphoma of the hard palate and pavement carcinoma of the tonsil. In the latter patient after irradiation of metastases of the pulmonary carcinoma in the mediastinum the thoracic spinal cord was affected. The onset of clinical symptoms occurred in these four cases between the 6th and 11th months after termination of actinotherapy, all MRexaminations were made 1 - 3 months later. In all patients nonomogeneous foci were detected at the level corresponding to the irradiated tumourous process and three times the spinal cord was markedly expanded by oedema. The authors draw attention to the importance of detection of postirradiation changes in the surroundings of the spinal cord (diffuse fatty degeneration of the bone marrow of vertebral bodies) for assessment of the etiology of the affection.

        Key words: MR imaging - radiotherapy, complications - myelopathy, differential diagnosis