Late paralyses of peripheral nerves after radiotherapy

On the basis of eleven observations in 10 patients carried out by the authors-nine cases of paresis of the brachial plexus, one case of paresis of the accessory nerve and one of femoral nerve--the problems of late paresis due to the irradiation of peripheral nerves are discussed. The development of these nerve lesions are primarily caused by radiation-induced fibroses and vasculopathies in the environment of the nerves. Several series of radiation appear to increase the risk of radiogenic pareses. With the frequently preferred application of megavolt therapy, a further increase in radiogenic nerve lesions may result.