Cervical cerebrospinal fluid venous fistula with syringomyelia treated with suboccipital decompression: illustrative case

Abstract

BACKGROUND Cerebrospinal fluid (CSF) venous fistulas are a recently discovered and underdiagnosed cause of spontaneous spinal CSF leak, which may lead to spontaneous intracranial hypotension. Most cases occur in the thoracic spine, and only 2 cases were reported in the cervical spine. Treatments include the epidural blood patch, fibrin glue injection, and surgical ligation of the fistula. OBSERVATIONS The authors report the treatment of a C6–7 CSF venous fistula, for which direct ligation was not feasible, with suboccipital decompression, leading to the complete resolution of the symptoms. Based on the clinical course and outcome in our patient, the authors summarize the previous theory and propose a hypothesis for the pathophysiology of headache and other symptoms in patients with CSF venous fistulas. LESSONS The symptoms of CSF venous fistulas may be linked not only to intracranial hypotension but also to the altered CSF dynamics induced by tonsillar herniation. Suboccipital decompression should be considered as a potential treatment option, especially in patients with Valsalva-induced headache who show a poor response to surgical ligation, patients in whom surgical ligation is not feasible, and patients with foramen magnum obstruction. Further investigation of the pathophysiology of CSF venous fistulas is warranted and should be performed in the future.

An Uncommon Case of Multiple, Recurrent Cerebrospinal Fluid Venous Fistulas

“…CVFs were only first ever documented in 2014; however, they are an extremely important cause of SIH [ 1 ]. Similar to other documented cases of CVFs including a case report by Hsieh et al and a case series of 42 patients by Duvall et al, our patient presented with the common symptoms of headache, tinnitus, and double vision [ 3 , 4 ]. Specifically, in 77% of patients reported by Duvall et al, new-onset Valsalva-induced headache was the first and most common presenting symptom.…”

“…Duvall et al also found that in 40/42 patients, fistulas were located in the thoracic region between T7 and T12 and only 2/42 patients had CVFs located in the cervical spine, both of them located between C7 and T1 [ 4 ]. On the other hand, Hseih et al reported a case of a 30-year-old woman with a history of Evans syndrome who presented with new-onset Valsalva-induced headache accompanied by mental fog, nausea, and a dragging sensation for four months [ 3 ]. She underwent a CT myelogram of the thoracic and cervical spine and was found with bilateral CVFs between C6 and C7 and was treated with surgical ligation.…”

“…The suggested mechanism of CVF leading to SIH is the rupture of an arachnoid villi at the level of a nerve root sheath, leading to a direct connection between the CSF and a paravertebral venous system, allowing a unidirectional CSF flow from the CVF and lowering the pressure of the subarachnoid space [ 2 ]. Symptoms can include double vision, headaches, and tinnitus [ 3 , 4 ]. Most reported cases of CVFs occur in the thoracic spine; only two cases have been reported in the cervical spine [ 2 ].…”

CSF‐Venous Fistula of the Clival Skull Base: A Unique Case Study and Literature Review

“…2 CVFs were initially described in neurosurgical literature in 2014 as a cause of SIH and have since been reported with increasing frequency. 3 Dural weakness or rupture of the arachnoid granulations along nerves likely contributes to the pathophysiology of CVFs, although they are still incompletely understood. In this patient, the initial clival fracture likely leads to an enlarging traumatic meningoencephalocele that eventually erode into the nearby veins causing a CVF.…”

“…There are no reported cases of CVFs in the clival skull base and only one previously reported case of skull base CSF leak causing SIH at the level of the porus acusticus 2 . CVFs were initially described in neurosurgical literature in 2014 as a cause of SIH and have since been reported with increasing frequency 3 . Dural weakness or rupture of the arachnoid granulations along nerves likely contributes to the pathophysiology of CVFs, although they are still incompletely understood.…”