Figure 2.

The same patient as in Figure 1. At 75 months after surgery, he presented with low back pain, bilateral lower-extremities numbness, and heavy walking. T2-weighted MRI showed a well-circumscribed intradural sacral lesion measuring 14×8.2×30.1 mm at S1–S2 level. Note that there is no local recurrence or residue at L1–L3 level; defects of L2 laminectomy.