Presentation
Back pain.
Patient Data
At T9/T10, on the left side of the cord, displacing the cord slightly towards the right, without appreciable cord signal abnormality is a lesion is of markedly low signal on T2, low signal on T1 (lower than the adjacent cord), and enhancement at its periphery, which is somewhat ill-defined.
On axial imaging the lesion can be seen occupying the left T9/T10 neural exit foramen. It is difficult to determine whether this lesion is intra or extra-thecal in location although based on axial imaging I favor the latter.
Best appreciated on sagittal T2-weighted imaging the central non-enhancing hypointense component is in close proximity to, and possibly continuous with the T9/T10 disc.
Conclusion: Left sided T9/T10 lesion has appearances that favor an extruded disc with surrounding reactive inflammatory enhancement, despite the relatively normal adjacent disc. The main differential is that of a meningioma with central calcification. This should be readily apparent on CT.
AT T9/10, there is mild disc space narrowing with prominent intradiscal calcification. There is an extradural lesion at T9-T10 impinging upon the left side of the thoracic cord. This demonstrates subtle areas of mineralization within it, corresponding to the low signal T1-T2 lesion on MRI. The lesion extends into the left T9-T10 intervertebral foramen. The lesion appears contiguous with the T9-T10 disc. The appearances are favored to represent a partially mineralized T9-T10 disc extrusion.
Case Discussion
The patient went on to have a laminectomy and resection of the lesion which confirmed the absence of tumor and supported the diagnosis of an extruded disc.
Histology:
MICROSCOPIC DESCRIPTION: Sections show diathermied fibroadipose tissue with foci of dystrophic calcification, hemosiderin laden macrophages and degenerative changes. No tumor is seen.
DIAGNOSIS: Fibroadipose tissue with degenerative changes.