Experience of thymectomy by median sternotomy in patients with myasthenia gravis

Objective: To determine the outcome of thymectomy in patients with myasthenia gravis and safety of median sternotomy approach. Methodology: An observational descriptive study was conducted in the department of thoracic surgery JPMC from February 2005 to January 2009. Twenty-two patients having persistent generalized or ocular myasthenia gravis referred to our department by neurologists and general physicians, partially or not responding to medical treatment with or without thymoma, were included in the study. Those who were not fit for anaesthesia were excluded. Preoperatively 2 to 3 sessions of plasmapheresis were done and each patient was given anti myasthenia gravis treatment. Clinical staging was done by Modified Osserman classification. Median sternotomy approach was used. Outcome was assessed on the basis of remission of disease in different Osserman groups. All patients were followed for a minimum of 6 months. Results: Out of 22 patients, 16 (72.7%) were females and 6 (27.2%) males. Mean age at presentation was 35.2 +/- 14.5 years. Mean duration of symptoms was 1.5 +/- 1.2 years. A total of 4 (18.1%) patients with myasthenia gravis had thymoma and histopathology of 18 (81.9%) patients showed thymic hyperplasia. Remission was seen in most grades of Osserman. The best response was seen in Grade I where all patients achieved remission. Most patients in Grade II A and II B were benefited. The only patient in Grade III had no improvement of symptoms. No patient in Grade IV underwent thymectomy. Overall 86.3% had a positive outcome on basis of remission and improvement. Conclusion: Thymectomy by median sternotomy is safe and effective with more favourable outcomes for patients of myasthenia gravis not responding to medical treatment (JPMA 60:368; 2010).