Imaging of Acquired Skull Base Cerebrospinal Fluid Leaks

Acquired skull base cerebrospinal fluid (CSF) leaks can result from trauma, tumors, iatrogenic causes, or may be spontaneous. Spontaneous skull base CSF leaks are likely a manifestation of underlying idiopathic intracranial hypertension. The initial assessment of rhinorrhea or otorrhea which is suspected to be due to an acquired skull base CSF leak requires integration of clinical assessment and biochemical confirmation of CSF. Imaging with high-resolution CT is performed to locate osseous defects, while high-resolution T2w MRI may detect CSF traversing the dura and bony skull base. When leaks are multiple or if samples of fluid cannot be obtained for testing, then recourse to invasive cisternography may be necessary.