Solitary dorsal intramedullary schwannoma

A LXHOUGH it has been reported that schwannomas (also called neurinomas or neurilemomas) comprise approximately' 30% of primary intraspinal neoplasms, ~3'37 intramedullary neurilemomas are rare. According to recent review papers, only 25 cases have been reported in patients who had no evidence of yon Recklinghausen's disease. ~.~-~42~' In addition, 11 cases of intraparenchymal schwannomas of the brain and brain stem have been reported. 2 Because the presumed cell of origin of the schwannoma is the Schwann cell, l~ which is not normally found within the parenchyma of the brain and spinal cord, it is not surprising that these lesions are rare. Several theories have been advanced to explain the presence of these tumors within the central nervous system (CNS). None has gained universal acceptance. We report an additional case of intramedullary schwannoma of the dorsal spinal cord and review the literature on these rare neoplasms. With the increasing use of magnetic resonance (MR) imaging as the initial diagnostic procedure and the preference for operative management of intramedullary tumors of all types, these lesions are expected to be encountered more frequently in the literature over the next years.