Presentation
Low back pain
Patient Data
A well-defined left paracentral intra-spinal epidural soft tissue is seen opposite to the L5 level, measuring about 25 x 17 x 15 mm at maximal CC, AP, and T diameters and eliciting isointense signal in T1 and slightly high signal in STIR, with peripheral enhancement in the post-contrast T1 fat sat images and lies immediately below L4-5 disc that shows annular tear, representing a sequestrated disc material. It is markedly compressing and displacing the thecal sac and cauda equina nerve roots to the right side.
L4-5 mild diffuse disc bulge is seen with left posterolateral tear and sequestrated disc material (described above).
L5-S1 diffuse disc bulge associated with left posterolateral and foraminal protrusion, indenting the thecal sac and causing moderate bilateral foraminal compromise.
Case Discussion
The sequestrated disc material follows the disc signal in all pulse sequences and enhances peripherally after intravenous contrast.
The differential diagnosis includes:
granulation tissue which shows diffuse and delayed enhancement
epidural abscess shows high T2 signal with thick marginal enhancement, end plate destruction, and surrounding soft tissue edema