Presentation
Strange sensations and functional loss in left leg.
Patient Data
Notice a focal anterior displacement of the spinal cord at the level T6-T7. The sagittal images show a focal anterior displacement of the spinal cord.
The axial images show an asymmetry in this displacement being more pronounced on the right side. On the right there is a herniation of spinal cord through a dural defect presenting as an extradural mass.
There is a focal enlargement of the subarachnoid space. Notice a normal flow void behind the spinal cord which makes an arachnoid cyst less probable as a cause for the herniation.
Case Discussion
Possible causes of spinal cord herniation are a history of (occult) minor trauma or herniated and/or calcified disk. This eventually could lead to thinning and rupture of the dura.
In the majority of cases no possible antecedent cause is identified and the dural defect is thought to be congenital or idiopathic in nature.
In our case there is no relevant history and also there are no obvious signs of disk pathology, so imaging features in this case are consistent with ventral cord herniation or idiopathic spinal cord herniation.