Clinical results of thymectomy in myasthenia gravis patients

Document Type : Original


1 Mashhad University of Medical Ghaem - Department of Thoracic and Cardiovascular Surgery

2 Professor of Neurology and Psychiatry Department of Qayim Hospital

3 Assistant Professor of the Lung Department of Qayim Hospital

4 Assistant professor of heart and thoracic surgery department

5 General practitioner


Introduction: myasthenia gravis is an autoimmune disorder affecting postsynaptic acetylcholine receptors of voluntary muscles. Since Blalock et al. first demonstrated the beneficial effect of thymectomy in 1939. The procedure has become increasingly accepted in the treatment of myasthenia gravis.
Materials and Methods: we studied clinical results of thymectomy in myasthenia gravis cases during 12 years retrospectively and antegradly. Our variables included: patient's age, sex, and signs at the time of admission, disease onset to operation interval, postoperative complications, and duration of hospitalization, thymus histology and clinical response to thymectomy. Data were analyzed appropriate analysis.
Results: 16 women and 11 men with median age of 29.8 (±12.7) years were operated on by median sternotomy approach. Thymectomy was done during less than 1 year after disease onset in 44%, 1-3 years later in 42% and later than 3 years in 14%. Most had mild to moderate generalized myasthenia. Thymic hyperplasia was reported to be the most common pathologic finding. Clinical response to thymectomy was good (70.4%). The best results were obtained in female less than 40 years old, with out thymoma, disease onset to operation interval less than 2 years and mild myasthenia.
Conclusion: Because of its high beneficial rate thymectomy is an advantageous therapeutic option. The chance of benefit increases when the history of myasthenia gravis is short and the stage of the disease is early.


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