Spinal cord gangliogliomas are rare, comprising 1.1% of all spinal cord tumors.

They are more frequent in children, representing 15% of intramedullary neoplasms in the paediatric age group.

As is the case with intracranial variety, spinal gangliogliomas occur predominantly in children and young adults. The mean age of presentation is 19 years. There is no gender predilection.

Clinical presentation is similar to that of other intramedullary spinal tumours, with pain, weakness and sensory changes common.

Gangliogliomas are WHO grade I or II neoplasms.

The most common location is the cervical cord, followed by the thoracic cord. Gangliogliomas may rarely involve the conus medullaris or the entire spinal cord (holocord presentation).

As is the case with other intramedullary spinal tumours plain films and CT have little to offer in the diagnosis and characterisation of spinal gangliogliomas. None the less a few features may be visible, including:

scoliosis

bony remodelling

posterior vertebral body scalloping

remodelling of the pedicle or posterior arch

cord expansion may be visible on CT and vague enhancement may also be seen following contrast administration

MRI

Gangliogliomas of the spinal cord typically involve long segments of spinal cord, often extending for greater than eight vertebral body segments. They are commonly eccentric in location. Approximately half (46%) of these tumours contain tumoral cysts 3.

Signal characteristics include:

T1: the mixed signal intensity of gangliogliomas on T1 weighted images is due to the dual cellular elements of the tumour and is a unique finding among spinal cord tumours.

T2 high intensity

surrounding oedema is uncommon

T1 C+ (Gd): most demonstrate patchy enhancement, however up to 15% cases may demonstrate no enhancement 2

gradient echo: calcification is common, and will appear as areas of low signal with blooming

Gangliogliomas are generally slow growing. Gross resection of the tumour is recommended. However, despite their low grade, there is a 27% rate of recurrence, which is approximately three to four times that of cerebral gangliogliomas, likely due to the increased difficulty of complete surgical excision of spinal tumours. Overall, there is an 89% 5-year survival rate after resection 3.

The main differential diagnoses are spinal astrocytomas and spinal ependymomas. In many instances a definite preoperative diagnosis is not possible as many of the features overlap, however some features are helpful in suggesting the diagnosis of a spinal ganglioglioma 6:

spinal astrocytoma

difficult to distinguish from gangliogliomas

majority enhance (used to be said that all enhance but this is not the case 7)

spinal ependymoma

average length of four or less vertebral body segments (whereas gangliogliomas often extend over a greater distance than this)

typically centrally located within the cord

the vast majority enhance

periapical cysts common

hemosiderin capping common

transverse myelitis

clinical presentation more acute

absent bony remodelling

central rather than eccentric

rapid resolution on follow-up imaging.