A 62 y.o. woman sp lumbar laminectomy comes in for back pain and headache

What do you see on her MIR?

hint: this is a T2 weighted image

Our patient had a pseudomeningocele  from L4-S1.   This is a collection of CSF which  occurs due to a CSF leak which is not contained within the dura like a true meningocele.  The most common causes of a pseudomeningocele are surgery or trauma.

a true meningocele or myelomeningocele(containing spinal cord) is covered with dura.

The majority of pseudomeningoceles resolve with time and aspiration but surgery is needed for the ones which develop external fistulas, infection or persistent intracranial hypotension.  Our patient had had two previous surgeries following her lumbar laminectomy to repair this CSF leak which were unsuccessful.  She developed E. coli meningitis and was treated with six weeks of IV antibiotics, then oral antibiotics. On arrival at Barnes she was taken to the OR for a lumbar drain and aspiration of the pseudomeningocele.   The lumbar drain is set at 10cc/hr.   Here CSF was no growth here.   Plans are being made to transfer her care to her previous spine surgeon.

While many pseudomeningoceles resolve spontaneously,  patients with infection or persistent symptoms of headache when standing( which implies low CSF pressures ) require surgery.  Pseudomeningoceles are more common in head and neck surgery and are reported 4.5% of the time in neurotologic procedures.

In the case below, after a cerebropontine angle tumor resection of a schwannoma, a pseudomeningocele developed which compressed the brainstem causing altered mental status.  Emergent surgery was needed.

this pseudomeningocele extended into the scalp on the L

Chiang,J, Lin H. Life-threatening posterior fossa cyst induced by pseudomeningocele after operation for acoustic neuroma.  2014. Surgical Neurology International.

Solomon P, Sekharappa V, Krishnan V, et al. spontaneous resolution of post operative lumbar pseudomeningoceles: A report of 4 cases. 2013 Indian Journal of Ortho Jul-Aug 47(4):417-421.

Hawk M, Kim K . review of spinal pseudomeningoceles and CSF fistulas. 2008. Neurosurg Focus. 9:e5