[Brain lesions after radiotherapy]

On the basis of literature reports up to 1988 the incidence, clinical pattern and treatment of cerebral complications following radiotherapy administered to the organs and tissues of the head are discussed. Acute radiation-induced reaction and early delayed reaction in the form of e.g. the so called somnolence syndrome or rhombencephalopathy are rare and their prognosis is usually good. In 1 to 14% of the patients delayed reaction may develop corresponding to the late radiation necrosis, usually with progressive unfavourable course. A problem of practical importance is the impossibility of differentiating radiation-induced cerebral necrosis from recurrence, expansion of the primary tumour or metastatic tumour, even using CT and MNR. Only the poorly available positron emission tomography makes possible differential diagnosis. Sometimes, surgical or pharmacological treatment of cerebral necrosis is effective.