Surgical and Neurological Outcome of Minimally Invasive Thymectomy in Patients With Myasthenia Gravis: An Experience of 100 Cases Over 6 Years at a Tertiary Care Center in North India

Background: Minimally invasive thymectomy (MIT) is emerging as an effective alternative to open thymectomy in the management of patients with myasthenia gravis (MG). The primary objective of our study is to assess the surgical and neurological outcome of MIT in patients with MG. Materials and Methods: It is a retrospective evaluation of prospectively collected data of 100 patients with MG, who underwent MIT from April 2012 to January 2018 at a tertiary care center in India. Surgical outcome was assessed for success of minimal invasive approach, conversion, perioperative morbidity, and postoperative hospital course. Neurological outcome was assessed, after at least 1 year of follow-up, according to Myasthenia Gravis Foundation of America postintervention status. Factors predicting complete stable remission (CSR) were evaluated. Results: MIT was successfully performed in 98% patients with 2% conversion. There was no mortality. Overall, 10% of patients had perioperative morbidity with 5% having exacerbation of neurological symptoms. Two of these needed postoperative ventilation, whereas 3 recovered on conservative treatment. Median operative time and hospital stay were 140 minutes and 3 days, respectively. At a median follow-up of 47 months, CSR was seen in 20% with improvement in 73.3%. Overall, 63% patients were taken off steroids and patients requiring 3 drugs decreased by 70.7%. There was significant reduction in the dosage of pyridostigmine (P<0.001), prednisolone (P<0.001), and azathioprine (P=0.002) after thymectomy. Milder disease (Myasthenia Gravis Foundation of America class 1 and 2) predicted CSR on multivariate analysis. Conclusions: MIT is a safe and effective procedure that leads to improvement in neurological status with significant reduction in number and dosage of medications after thymectomy. Mild disease predicts CSR.