Male, 11 years old, status post L5-S1 hemilaminectomy for resection of a left S1 extra dural mass. Three month follow-up examination. Postoperative findings are again seen compatible with prior left laminectomy at S1, S2 and partially at L5 for resection of the previously seen cystic lesion. Postoperative edema in the operative bed has resolved. Amorphous soft tissue thickening with low level enhancement in the operative bed is compatible with scarring.At the site of the resected lesion, along the ventral epidural space at the proximal left L5 neural foramen, a 6 x 6 mm T2 hyperintense structure with a hypointense rim is detected (see image 37 series 501). No such finding was evident on the prior exam, though the area may have been obscured by edema.Elsewhere, spinal canal contents are within normal limits. No significant canal or foraminal compromise is suspected. Vertebral body morphology and signal characteristics are within normal limits. Alignment is anatomic.
1.Redemonstration of postoperative findings reflecting prior resection of a cystic lesion from the ventral epidural space at the level of the proximal left L5 neural foramen.2.A 6 x 6 mm T2 hyperintense structure with hypointense rim is identified at the site of the prior lesion which seems to be new compared to prior, though it may have been present but obscured by edema. This could represent residual surgical distortion, but the possibility of a small residual or recurrent component of the original lesion must also be considered. Continued imaging followup is advised.