Images in Neurosurgery

Anterior Sacral Meningocele, Scimitar Sacrum

The patient is a 25-year-old female with a history of presacral mass found on routine pelvic examination five years previously. Current examination was for sacral and coccygeal aches in addition to urinary frequency. She was neurologically intact. On imaging, the mass had increased in size (Figure 1).

Figure 1: Sagittal T2 view of lumbosacral spine showing meningocele
arising from terminal dural sac.

The lesion communicated with the dural sac at the coccygeal tip and did not enhance. There was auto-fusion of L3-4 vertebral bodies. A myelogram and operation were planned. Disruption of caudal eminence development and secondary neurulation can result in a spectrum of disorders, including anterior sacral meningocele, scimitar sacrum, sacral agenesis, sacrococcygeal dermoids and teratomas, and anomalous development of the anorectal, urinary, and genital tracts (Figure 2).

These disorders are thought to be more common in females, and may be related to X-linked or autosomal dominant inheritance.

Figure 2: AP view of pelvis to show scimitar sacrum.

Submitted by:
Osama Kashlan, MD, Paul Park, MD, and Suresh Ramnath, FRCSC

Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA