Answer of August 2008

Clinical History:

48-year-old lady with persistent back pain and MRI was done.

A 48-year-old lady presented to us with persistent back pain.  She has suffered from lower limb pain and numbness consistent with right sciatica for years.  On physical examination, there is reduced sensation over L4 to S1 dermatome and right-sided power loss over L5 myotome.

Diagnosis:

Epidural lipomatosis

Discussion:

The thecal sac terminates at the inferior aspect of L5, which is higher than expected (S2).  The more inferior spinal canal is filled with fat, the signal of which is consistent with the adjacent subcutaneous fat and is suppressed on STIR sequence.  There is incidental finding of a Tarlov cyst.
Patient underwent decompression surgery with right L5 laminotomy and debulking of the epidural lipomatosis.
The patient enjoys satisfactory post-operative outcome with relief of symptoms.