[Thoracic neurinoma: a rare tumor of the posterior mediastinum]. / Das thorakale Neurinom: ein seltener Tumor des hinteren Mediastinums.

Neurogenic tumors of the thorax are seen mainly in young adults and children. Most of them are small, benigne, unilateral and extraspinal. Benign lesions are always almost asymptomatic, the malignant ones symptomatic. It must be sure preoperative, whether the tumor has an intraspinal component. In case of the benign neurogenic tumors, the anatomical extension is more important than the histological type of tumor, intraspinal canal extension makes necessary a combined surgical-neurosurgical procedure. Recurrence of a benigne lesion is unusual, prognosis of malignant neurogenic tumors of the thorax is poor.

Neuromuscular function and plasma drug levels in pyridostigmine treatment of myasthenia gravis.

In 18 patients with generalised myasthenia treated with oral pyridostigmine, muscular strength, decrement of neuromuscular transmission in the trapezius muscle on repetitive accessory nerve stimulation, and pyridostigmine plasma level were measured repeatedly during 1-3 dosing intervals. Significant correlations between pyridostigmine concentrations and functional parameters were present in three out of 11 cases in which plasma levels changed by at least 25 ng/ml during the investigational period and peak levels did not exceed 100 ng/ml. Several other observations indicated that pyridostigmine at levels above 100 ng/ml may impair neuromuscular function.