Extramedullary Intradural Spinal Tumors

Abstract

Spinal tumors comprise 15% of all central nervous system tumors. Their annual incidence is 2 to 10 per 100,000, and 90% of affected patients are older than 20 years. The most common spinal tumor location is extradural, with cancer metastasis being the most common tumor; primary extradural vertebral bone tumors are less frequent. Most spinal tumors are extradural (50%-55%), whereas 40% to 45% are intradural. Furthermore, 5% are intramedullary and 40% are extramedullary. The most common tumors are schwannomas (29%) followed by meningiomas (25%) and gliomas (22%).Extramedullary intradural spinal tumors (EISTs) are rare. They comprise about 40% to 45% of all spinal tumors. They are distinguished from intramedullary tumors by their extraaxial location. The fi rst recorded resection of an EIST was performed in 1888 by Horsley, in a 42-year-old patient. The lesion was classifi ed originally as a fi bromyxoma, but it probably was a degenerated schwannoma. The mean age of patients with EISTs is 46 years, and 54% to 57% of patients are men.

CSF-Related Complications After Intradural Spinal Tumor Surgery: Utility of an Autologous Fat Graft

“…In our earlier practice, CSF-related complications were similar to those reported by other authors ( 1 - 3 , 6 , 7 , 9 , 11 - 14 , 17 - 19 , 22 , 23 , 25 , 26 ). As a consequence, we have prospectively adopted the intraoperative use of autologous fat grafting.…”

Two Cases with Incidental Finding of Large Asymptomatic Intradural Lumbar Tumors

“…Incidental spinal lesions are divided into intraosseous vertebral spinal lesions identified within the actual vertebrae or disc space distinguishing them from intraspinal lesions [ 5 - 7 ]. The vertebrae are the most common location for incidental findings, comprising 70–80% of incidental spine lesions and commonly include hemangiomas, unsuspected osteoporotic fractures, intraosseous tumors, and unsuspected spinal metastasis [ 7 , 8 ]. Lesions within the spinal canal or neural foramina are defined as intraspinal, are less frequent, but can include migrated disc fragments and commonly include Tarlov cysts, lipomas, tethered cord and thickened filum terminale, dermoid and other developmental tumors and much more infrequently intradural or extradural tumors [ 9 - 12 ].…”

“…Besides the obvious location within the spinal canal, differentiating these lesions depends on a combination and comparison using CT reconstruction possible identifying intra-tumoral calcification, existence of adjacent vertebral erosion and detecting enhancement on CT contrast. Classification of intraspinal masses using MRI with and without using Gadolinium contrast can demonstrate patterns of enhancement commonly seen with tumors [ 8 , 9 ]. Included in the radiologic differential diagnosis of an intraspinal mass is always an extruded disc fragment which can migrate within the epidural space and rarely even intradurally but will not have gadolinium enhancement.…”

“…Often intraspinal tumors can have a latent period without symptoms and even when initially symptomatic these tumors can be clinically confused with symptoms of lumbar disc degeneration [ 12 - 14 ]. Review of large surgical series demonstrates the presenting symptoms are a mixture of gradual lumbar pain with and without radiculopathy progressing on to cauda equina syndrome, however, there is commonly a delay in diagnosis since other causes of lumbar pain and radiculopathy are often initially suspected such as herniated disc and spinal degeneration [ 8 , 13 , 14 ].…”

“…There were no tumors in this series [ 6 ]. Lumbar and thoracic intradural tumors presenting as incidental, asymptomatic findings, are very uncommon comprising less than 0.05% of large series of incidental MRI studies [ 8 , 13 ]. Spinal tumors comprise 15% of all central nervous system tumors.…”