Migrated disk fragment

There is mild loss of disk space height (and thus substance) at L5-S1. A left paracentral disk herniation is noted, at this level, together with superior migration. Note the slight hyperintensity of the superiorly migrated portion of the disk on the T2-weighted scan, consistent with a free fragment (which is also suggested by the extent of migration of disk material). There is marked compression of the S1 nerve roots on the left prior to their exit from the thecal sac.

Migrated disk fragment
Part of the on-line supplement to Neuroradiology – The Essentials with MR and CT (© 2015)