The historical evolution of microvascular decompression for trigeminal neuralgia: from Dandy's discovery to Jannetta's legacy.

Although the symptoms of trigeminal neuralgia (TN) have been well described throughout the history of medicine, its etiology was initially not well understood by most surgeons. The standard procedure used to treat TN today, microvascular decompression (MVD), evolved due to the efforts of numerous neurosurgeons throughout the twentieth century. Walter Dandy was the first to utilize the cerebellar (suboccipital) approach to expose the trigeminal nerve for partial sectioning. He made unique observations about the compression of the trigeminal nerve by nearby structures, such as vasculature and tumors, in TN patients. In the 1920s, Dandy unintentionally performed the first MVD of the trigeminal nerve root. In the 1950s, Palle Taarnhøj treated a TN patient by performing the first intentional decompressive procedure on the trigeminal nerve root solely through the removal of a compressive tumor. By the 1960s, W. James Gardner was demonstrating that the removal of offending lesion(s) or decompression of nearby vasculature alleviated pressure on the trigeminal nerve and the pain associated with TN. By the 1990s, Peter Jannetta proved Dandy's original hypothesis; he visualized the compression of the trigeminal nerve at the root entry zone in TN patients using an intraoperative microscope. In this paper, we recount the historical evolution of MVD for the treatment of TN.