Thymectomy in the Management of Myasthenia Gravis

There continues to be a debate regarding the effectiveness of thymectomy in the treatment of nonthymomatous myasthenia gravis (MG) and, when undertaken, which thymectomy technique is the procedure of choice. The debate persists primarily because of the lack of controlled prospective studies. Analysis has been complicated by the absence, until very recently, of accepted objective definitions of severity of the illness and response to therapy as well as variable patient selection, timing of surgery, type of surgery, and methods of analysis of results. Without resolution of these issues by properly controlled prospective studies, there can be no unequivocal determination of the effectiveness of thymectomy or valid comparison of the various thymectomy techniques. In this review, based on previous analyses, attempts will be made to clarify some of the controversial issues concerning thymectomy for nonthymomatous MG and make limited recommendations based on the best available evidence.

KEYWORDS

Nonthymomatous myasthenia gravis - transcervical thymectomy - transsternal thymectomy - video-assisted thoracic surgery “VATS” thymectomy - life table analysis - crude analysis - nonrandom prospective studies

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