PT  - JOURNAL ARTICLE
AU  - Carl V. Bundschuh
AU  - Michael T. Modic
AU  - Jeffrey S. Ross
AU  - Thomas J. Masaryk
AU  - Henry Bohlman
TI  - Epidural Fibrosis and Recurrent Disk Herniation in the Lumbar Spine: MR Imaging Assessment
DP  - 1988 Jan 01
TA  - American Journal of Neuroradiology
PG  - 169--178
VI  - 9
IP  - 1
4099  - http://www.ajnr.org/content/9/1/169.short
4100  - http://www.ajnr.org/content/9/1/169.full
SO  - Am. J. Neuroradiol.1988 Jan 01; 9
AB  - Twenty patients were enrolled in a prospective study to evaluate MR imaging in the differentiation of epidural scar and herniated disk material. Fourteen patients had surgical verification of imaging findings. In 12 (86%) of these patients, the MR interpretations fully agreed with the observations at surgery. Careful integration of the findings on sagittal and axial T1-weighted images with more T2-weighted axial images was important for analysis. Anterior and lateral recess scars were hypo- or isointense on T1-weighted sequences and hyperintense on more T2-weighted sequences relative to the “parent” anulus intensity. Free fragments demonstrated a slightly hyperintense signal intensity on T1-weighted images relative to epidural fibrosis but had a similar hyperintense signal intensity on T2-weighted sequences. Prolapsed or extruded disk fragments were hypo- or isointense relative to the parent anulus on all sequences. Morphology, epidural location, mass effect, and often signal intensity were the important parameters by which scar and herniated disk could be differentiated with MR.