Surgical treatment for myasthenia gravis.

A new surgical technique for thymectomy is presented. Three hundred and seventeen patients with myasthenia gravis and 20 with thymomas who had myasthenic symptoms were operated on. The new surgical approach--a small transverse sternotomy--was used in 257 cases (in 240 patients with myasthenia gravis and 17 with thymomas) and conventional median sternotomy in 80. In myasthenic patients small transverse sternotomy enabled radical thymectomy to be performed with an uneventful postoperative course and very good cosmetic results. There were no hospital deaths among patients with myasthenia gravis after thymectomy. The long term results, assessed after 18-24 months, were good: the total remission rate was 39.5%, and there was a great improvement in 48.5% and an improvement in 9%. After thymectomy about 30% of patients received supplementary treatment with prednisone. A correlation between the duration of symptoms and the result of thymectomy was established: the shorter the duration of myasthenia gravis the better the results. In the small group of 20 patients with thymomas two died in hospital. In 12 patients with encapsulated thymic tumours the long term results were similar to those in patients with myasthenia gravis, whereas in patients with infiltrating thymic tumours the results were unsatisfactory.