Experience with the "da Vinci" robotic system for thymectomy in patients with myasthenia gravis: Report of 33 cases

Background. Our initial experience in applying robotic-assisted technologies for the treatment of myasthenia gravis (MG) in patients without thymoma is reported. Methods. from April 2002 to October 2004, 33 patients (24 females and 9 males; mean age, 41 years), with clinical nonthymomatous myasthenia gravis, underwent robotic thoracoscopic thymectomy using the "da Vinci" (Intuitive Surgical, Inc, Mountain View, CA) system and adopting a 3 port, left-sided approach. Results. Mean operative time was 120 minutes. No intraoperative complications or surgical mortality is reported and postoperative complications occurred in two patients (6%). Mean hospital stay was 2.6 days (range, 2-14 days). Histologic analysis of surgical specimens revealed 23 hyperplasia, 4 normal thymus, 4 atrophy, and 2 thymomas; in 12 patients (36.3%) ectopic thymic tissue was found. Follow-up evaluation of the first 24 patients (mean, 23.8 months; range, 12-31 months) showed that 4 patients (16.7%) had complete remission and 18 (75%) had significant clinical improvement for a global benefit rate of 91.7%. Conclusions. In patients with MG, robot-assisted thymectomy can be performed safely and efficiently. The improved visualization and dexterity of this instrument and its advanced technology may facilitate the minimally invasive approach to the thymus. We prefer to use the left-sided approach because it provides an enhanced visualization of the aortic window and it reduces the probability of phrenic nerves injury. A longer follow-up is necessary to verify long-term clinical results.