Intramedullary: Astrocytoma Astrocytomas Astrocytomas are the second most common spinal intramedullary glioma. They are the most common primary spinal cord neoplasms in children. Epidemiology Lack of sex predilection. 24–30% of adults Up to 90% of children 3rd and 4th decades for adults.

Location Thoracic (most say cervicothoracic 50% in upper thoracic) Location Thoracic (most say cervicothoracic 50% in upper thoracic). Eccentric in the spinal cord. Enhancement Heterogeneous, mild to moderate, partial. Borders Ill defined. It may contain Cysts, necrosis, or hemorrhage. Signal characteristics include: T1WI: Hypointense to Isointense T2WI: Hyperintense (mild).

Intramedullary: Ependymoma Ependymoma is the most common primary cord neoplasm They are slow-growing, benign, well-circumscribed lesions that may be focal or involve long segments of the cord. They commonly occur within the conus and filum terminale but may be found anywhere in the spinal cord.

Location Epidemiology Signal characteristics include: Cervical, conus, filum terminale (MP) Centrally located in the cord. Epidemiology There is no sex predilection, 60% of adult, 30-60yrs of life. Signal characteristics include: T1WI: Hypointense (Except MP which can be hyperintense). T2WI: Hyperintense (mild).

Ependymoma

Enhancement Homogenous, may be only mild and moderate. Borders Well defined. May be associated with: Edema, cystic degeneration, haemorrhage, calcium, spinal cord cyst and hemosiderin cap.

6 Histological subtypes of ependymoma Cellular (the most common intramedullary type) Papillary Clear cell Tanycytic Myxopapillary Virtually always located along the filum terminale with occasional extension into the conus medullaris 6. Melanotic (the least common type)

Intramedullary: Syringohydromyelia Seen with: Congenital lesions Chiari I & II Tethered cord Acquired lesions Trauma Tumors arachnoiditis Idiopathic