[Muscular biopsy in myasthenia gravis: histochemical and morphometric study of 4 cases].

Myasthenia gravis is a neuromuscular disease characterized by excessive fatigability of muscle function and particularly involves muscles innervated by the cranial nerves. It is believed that the defect is in the neuromuscular junction. The authors studied histochemical and morphometric findings in 4 patients with myasthenia gravis showing that the type II fibres were significantly smaller than the type I fibres.