Medullary venous hypertension secondary to a petrous apex dural arteriovenous fistula: a case report

[Multiple dural arteriovenous fistulas showing isolated subcortical white matter T2 hyperintensity with gadolinium enhancement]

We describe a 44-year-old man with a complaint of atonic seizures of the left upper limb, followed by generalized seizures. Brain MRI showed isolated juxtacortical white matter T2 hyperintensity with gadolinium (Gd) enhancement of the adjacent cortical gray matter and subcortical white matter in the right frontal convexity. Treatment with levetiracetam was effective for seizure suppression, and he had no other neurological abnormalities. Human leukocyte antigen typing revealed B54 and Cw1, which indicated the possibility of neuro-Sweet disease. However, a general examination, which included vital signs and eye and skin findings, was normal. A cerebrospinal fluid test showed a mild elevation in protein levels without pleocytosis and a normal range of interleukin-6. Electroencephalography showed intermittent slow waves without epileptic discharge in the bilateral temporal lobes. We detected subtle flow voids in the pia mater of the left frontal lobe, which suggested cerebrovascular disease, and specifically, the possibility of dural arteriovenous fistulas. Computed tomography angiography showed abnormally dilated perimedullary veins in the left frontal lobe. Cerebral angiography confirmed the existence of four dural arteriovenous fistulas, which included two retrograde leptomeningeal venous drainages in the right frontal cortical veins supplied by the anterior branch of the right middle meningeal artery. The other dural arteriovenous fistulas were retrograde leptomeningeal venous drainages in the left frontal cortical veins supplied by the anterior and posterior convexity branches of the left middle meningeal artery. The patient underwent successful endovascular embolization of all dural arteriovenous fistulas with Onyx injection. A follow-up MRI showed gradual improvement of the T2 hyperintensity and Gd enhancement. He remained seizure-free for 2 years following endovascular embolization.

Endovascular treatment for dural arteriovenous fistulas in the petroclival region

Petroclival region dural arteriovenous fistulas (DAVFs) are rare and difficult lesions to manage. They often have very complex anatomical structures and can be further divided into the superior petrosal sinus, petrous apex, inferior petrosal sinus, upper clival, and upper clival epidural-osseous DAVFs. Most petroclival region DAVFs should be treated due to their high Cognard grades. Currently, endovascular treatment (EVT) has become the first-line therapeutic option for petroclival region DAVFs. But not all the petroclival region DAVFs could be cured with EVT. When the arterial feeders are large or the DAVF is adjacent to the venous sinus, the success rate may be higher. In petroclival region DAVFs, if EVT can be performed successfully, satisfactory outcome can be anticipated. However, there are some inadvertent complications, which include cranial nerve palsy, subsequent sinus thrombosis, and migration embolization of the internal carotid artery and vertebral artery. Currently, a review of the EVT of petroclival region DAVFs is lacking. In this article, we performed a review of the relevant literature on this issue. In addition, some illustrative cases would be provided to elaborate these specific entities.

Spontaneous Resolution of Venous Aneurysms After Transarterial Embolization of a Variant Superior Sagittal Sinus Dural Arteriovenous Fistula: Case Report and Literature Review

We present a rare case of dural arteriovenous fistula (DAVF) with subarachnoid hemorrhage and intraventricular hemorrhage due to its venous aneurysms. A 63-year-old woman was admitted for a sudden loss of consciousness. Computed tomography angiograph, magnetic resonance imaging angiography, and digital subtraction angiography revealed a superior sagittal sinus DAVF. The fistula was fed by the left middle meningeal artery and left internal carotid artery, and was drained by a right vein of Trolard, the superficial Sylvian vein, deep Sylvian vein, and basal vein to the vein of Galen. The drainage veins were enlarged obviously with 3 aneurysmal venous malformations. There was a stenosis segment on the right basal vein. All the anatomic factors of direct cortical vein drainage, normal deep vein drainage, long tortuous drainage vein, outflow restriction, and multiple venous aneurysms, were contributed to the aggressive presentation of our case. Transarterial complete embolization of the fistula with balloon protection was successfully performed. Nine months later, a follow-up magnetic resonance imaging showed a complete disappearance of the 2 venous aneurysms located in the deep Sylvian vein and basal vein, and an obvious decrease in size of the venous aneurysm of the superficial Sylvian vein. This is the first report of a DAVF with 3 ballooned venous aneurysms and a spontaneous anatomy resolution of the venous aneurysms after the embolization of the fistula. At the same time, the clinical and radiologic characteristics of variant superior sagittal sinus DAVFs were summarized by review of the literatures reported previously.

Risk factors for dural arteriovenous fistula intracranial hemorrhage

To our knowledge, the risk factors for intracranial hemorrhage from dural arteriovenous fistula (DAVF) have not been systematically described, due to the complexity of their anatomy and low incidence. We performed this retrospective study to investigate the DAVF factors predicting intracranial hemorrhage. A 10year database of 144 consecutive patients with DAVF was reviewed. Data collected and analyzed were demographics, morphologic features of DAVF, sex, age, fistula flow rate, arterial supply, lesion location, and venous drainage pattern. Linear univariate and multivariate logistic regression analyses were used to evaluate the association between influencing factors and hemorrhage. A first linear univariate analysis was performed for all influencing factors, and showed that sex, lesion location, and venous drainage pattern were statistically significant in predicting intracranial hemorrhage (p<0.05). Secondary multivariate logistic regression analysis with sex, lesion location, and venous drainage pattern showed that only venous drainage pattern was statistically significant in predicting intracranial hemorrhage (p<0.05). Therefore, venous drainage pattern, particularly the cortical venous drainage, significantly predicts intracranial hemorrhage from DAVF. Both sex and lesion location may be confounding factors in predicting intracranial hemorrhage from DAVF, while the other factors may not be associated with hemorrhage.