Objective      To study the outcome of surgical treatment of myasthenia gravis (MG) by thymectomy via video-assisted thoracoscopic surgery (VATS) and partial sternotomy.       Methods      Thirty-two cases of MG were treated by thoracoscopic thymectomy along with mediastinal fat cleaning via right anterior-lateral approach (VATS group) and 40 cases were treated by by transsternal thymectomy via partial sternotomy (transsternal group) from April 2001 to September 2006.       Results      In VATS group

thoracoscopic thymectomy was performed successfully in 31 cases and additional thoracotomy was employed in 1 patient because of the injury of the left anonymous vein by electric coagulation claw during VATS. There was no postoperative mortality or MG crisis. In transsternal group

1 patient died 2 days after operation because of acute cardiac infarction

5 cases of MG crisis occurred postoperatively and all recovered after respiratory support. Compared with transsternal group

the operation time and hospital days were both shorter in VATS group. The postoperative dose of mestinon bromid and MGFA scores were both decreased in the two groups (VATS group P0.01

transsternal group P0.05).        Conclusion      Thymectomy by VATS via right anterior-lateral approach is technically feasible and safe. Compared with the transsternal thymectomy via partial sternotomy

it still has advantages of minimal invasion

less complications and rapid recovery.