Age / Sex : 75 / M

Chief complaint : Low Back Pain, Bilateral Lower Extremity Radiating Pain

PMHx : s/p Lumbar disc operation (50YA), s/p Cervical disc operation (4MA)

Question: What is the radio-opaque material in the central canal of C-T-L spine (&intracranial aspect) ?
Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).

Courtesy of Eugene Lee, Seoul National University Bundang Hospital

Discussion

Answer:  Intradural Oil-based contrast agent

Findings:

• Multifocal intradural tiny calcifications along the whole spinal canal


• probable previous oil-based contrast myelography related finding


• A well-defined cystic lesion within the dural sac from L4 to S1 level


• probable arachnoid cyst related with adhesive arachnoiditis

Differential Diagnosis: arachnoiditis Ossificans

Discussion:

• Myodil, and oil based positive contrast media, now discontinued, was widely used for performing myelography 30–70 years ago


• Myodil remained widely used substance until 1980s, gradually becoming replaced by water soluble contrast media


• Side effects: arachnoid adhesion (1%), and arachnoid cysts


• Half time: months or even years


• Imaging


• CT : Intradural radio-opaque dots


• T1WI : Hyper-intense signal intradural lesions


• T2WI: Iso-intense to hypo-intense intradural lesions

References:

• J spinal Cord Med 2012; 35:187–190