Where do you think this lesion is located?
Although much of the cord is of increased T2 signal, the conus appears to be the most affected. It also demonstrates subtle contrast enhancement.
What is the differential diagnosis?
These lesions can be difficult to categorically diagnose on imaging alone, and the presentation and clinical history is important. The main differential is between a diffuse spinal cord neoplasm (e.g. astrocytoma) and an inflammatory process (e.g. extensive transverse myelitis). A spinal dural arteriovenous fistula can have similar appearances, with increased T2 signal and vague enhancement, but tends to be associated with visible flow voids over the dorsal surface of the cord.
The whole of the thoracic cord from the level of the C7/T1 disc through to the conus is slightly expanded and displays abnormal signal within the grey matter. The central canal is slightly dilated up to a maximum of 3 mm in diameter in the mid thoracic cord. No abnormal vessels are detected. Post contrast views show slight, diffuse contrast enhancement, maximal in the conus and lower thoracic cord. The conus terminates opposite L2.