Spontaneous spinal CSF leaks are best known as a cause of
orthostatic headache, but may also be the cause of
coma. The authors encountered a unique case of a spontaneous spinal CSF leak causing
coma 2 days after
craniotomy for clipping of an unruptured
aneurysm. This 44-year-old woman with
autosomal dominant polycystic kidney disease underwent an uneventful
craniotomy for an incidental anterior choroidal artery
aneurysm. No intraoperative spinal CSF drainage was used. Two days after surgery the patient became
comatose with a left
oculomotor nerve palsy. Computed tomography scanning revealed a right extraceberal
hematoma and loss of gray-white matter differentiation. The
hematoma was evacuated and a diagnosis of
hemodialysis disequilibrium syndrome was made. Continuous
hemodialysis and hyperosmolar
therapy were instituted without any improvement. The CT scans were then reinterpreted as showing sagging of the brain, and the patient was placed in the Trendelenburg position which resulted in prompt improvement in her level of consciousness. A CT myelogram demonstrated an upper thoracic CSF leak that eventually required surgical correction. The patient made a complete neurological recovery. Neurological deterioration after
craniotomy may be caused by brain sagging caused by a spontaneous spinal CSF leak, similar to
intracranial hypotension due to intraoperative lumbar CSF drainage.