Atraumatic Cranial CSF Leaks

This article reviews the most common presenting symptoms and radiographic findings of atraumatic cranial CSF leaks, surgical management of skull base leaks, and postoperative management of idiopathic intracranial hypertension (IIH).

IIH is now widely accepted as a causative factor in the development of thinning of the bone of the anterior and lateral skull base and formation of encephaloceles or arachnoid granulations through the skull base with resulting CSF leaks into the aerated sinuses or middle ear and mastoid cavities. Demographic characteristics and presenting symptoms may differ slightly between patients with IIH and those with CSF leaks, but in both populations, management of elevated intracranial CSF pressure is required. Dural venous stenosis is associated with both conditions, and stenting of transverse or sigmoid sinus stenotic segments is now considered a treatment option for IIH.

Atraumatic cranial CSF leaks present with clear fluid either dripping from the nose or accumulating in the middle ear and mastoid because of bony and dural defects in the anterior or lateral skull base. Cranial CSF leaks are often associated with IIH, and treatment requires both repair of the skull base defects and management of IIH. Timely diagnosis and treatment of CSF leaks and IIH are necessary to prevent meningitis and decrease the risk of recurrence of leaks or sequelae of IIH. Patients with these CSF leaks should be evaluated for IIH by imaging or postoperative lumbar puncture with opening pressure because pressure may increase further once the CSF leak is repaired. Medication, weight loss, and CSF shunting are management options for elevated CSF pressure, but imaging for intracranial venous stenosis should be considered with venous stenting for treatment of elevated venous pressure.