Spontaneous closure of cerebral dural arteriovenous fistulas with direct cortical venous drainage. A case report

Spontaneous closure of a superior sagittal sinus dural arteriovenous fistula with an extensive angioarchitectural network: A case report and systematic review of the literature

BACKGROUND

Intracranial dural arteriovenous fistulas (DAVFs) have been documented to occasionally spontaneously regress. However, the mechanism responsible for this occurrence remains speculative.

METHODS

We present a case of a Borden II - Cognard IIa+b DAVF involving the superior sagittal sinus (SSS) with bilateral external carotid artery supply that regressed spontaneously. A systematic literature review was conducted to explore the current theories explaining the spontaneous regression of DAVFs according to Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.

RESULTS

A total of 26 studies and 54 cases were included in our results. Of the included cases, 57.14% of cases were Borden I, 16.33% were Borden II, and 26.53% were Borden III. Ruptured status or intracranial hemorrhage was documented in 24.1% of all cases, the majority of which (69.2%) were in cases with aggressive lesions (Borden II or greater). The most commonly involved location was the transverse sinus (38.89% of cases, n = 21), and the SSS was only involved in 12.96% of all cases. 50% of included cases proposed a mechanism responsible for spontaneous regression. The most frequently proposed mechanisms were thrombosis of the involved sinus/chronic inflammatory changes or direct endothelial injury, endoluminal stasis, and thrombogenic effects of contrast medium during angiography. We present the case of a 54-year-old woman with an aggressive ruptured DAVF that likely developed following a pediatric traumatic brain injury that was left untreated before she presented to our institution after significant delay. Her DAVF regressed on repeat angiography before neurovascular intervention without a clear identifying mechanism as proposed by the current literature.

CONCLUSION

Our results suggest that spontaneous regression is not necessarily associated with lower risk DAVFs. The present case offers a unique long-term insight into the natural history of an aggressive ruptured DAVF of the SSS that regressed without intervention. Further research into the natural history of DAVFs will be helpful in deducing key factors leading to spontaneous regression.

Intracranial dural arteriovenous fistula: a comprehensive review of the history, management, and future prospective

Dural arteriovenous fistulas (DAVF) are abnormal acquired intracranial vascular malformations consisting of pathological connections located within the dura between the pial arteries and the veno vasora, comprising the walls of the dural sinuses, bridging veins, or transosseous emissary veins. Dural arteriovenous fistulas are distinguished from arteriovenous malformations by their arterial supply from the vessels that perfuse the dura mater and lack of a parenchymal nidus. They are most commonly situated at the transverse and cavernous sinuses. The mechanism of development behind dural arteriovenous fistula can be explained by the molecular and anatomical factors. Multiple classification systems have been proposed throughout history including; Djindjian and Merland, Cognard, and Borden classification systems. The aggressiveness of the clinical course in intracranial dural arteriovenous fistula can be predicted through the angiographic patterns of venous drainage, more specifically, the presence of cortical venous drainage, the presence of venous ectasia, and the aggressiveness of clinical presentation. Intracranial dural arteriovenous fistulas might be discovered incidentally. However, if symptomatic, the clinical presentation ranges from mild neurological deficits to severe, lethal intracranial hemorrhage. Angiography is the imaging of choice to investigate, diagnose, and plan treatment for intracranial dural arteriovenous fistula. The management algorithm of intracranial dural arteriovenous fistula can be broadly divided into conservative, surgical, endovascular, and/or radiosurgical options. With the advent of endovascular therapies, surgery has fallen out of favor for managing intracranial dural arteriovenous fistulas. In the present article, the pathophysiology, classifications, natural history, clinical manifestations, radiological features, management, and complications are comprehensively reviewed.

Spontaneous closure of non-cavernous sinus dural arteriovenous fistulas: A case series and systematic review of the literature

BACKGROUND AND PURPOSE

To report 9 new cases of non-cavernous sinus dural arteriovenous fistulas (NCS-DAVFs) that closed spontaneously and systematically review reports of other cases in the literature.

MATERIAL AND METHODS

We performed a retrospective analysis of 9 cases from 2 institutions of NCS-DAVFs that closed spontaneously. Using PubMed and Scopus in accordance with the PRISMA guidelines, we systematically reviewed English language articles about NCS-DAVFs showing spontaneous closure.

RESULTS

Review of the cases from 2 institutions identified 9 cases of NCS-DAVFs showing spontaneous closure in follow-up magnetic resonance angiography (MRA), and the systematic review of the literature yielded an additional 38 cases, which had been diagnosed by repeated arteriography. Collectively, the patients included 23 men and 24 women with a mean age of 54 years. The shunts were located in the transverse-sigmoid sinus in 24 cases (51%), anterior condylar confluence in 11, and other locations in 12. Based on the venous drainage pattern on arteriography, 27 cases (57%) were classified as low-risk NCS-DAVF (without cortical venous reflux) and 17 were classified as high-risk NCS-DAVF (with cortical venous reflux). Shunt closure was observed within 3 months in 17 cases (36%). Extrinsic predisposing factors for shunt closure were detected in 14 cases (30%). These included angiography in 7 cases, sinus recanalization in 4, development of sinus occlusion in 2, and sinus compression by a newly developed hematoma in 1.

CONCLUSION

Spontaneous closures of NCS-DAVFs can occur for both high- and low-risk types. One-third of these closures occur within 3 months.

Spontaneous Closure of a Cavernous Sinus Dural Arteriovenous Fistula with Spinal Perimedullary Drainage (Cognard V) during Attempted Transvenous Embolization

The authors describe a patient with spontaneous closure of a spontaneous cavernous sinus dural arteriovenous fistula (CSDAVF), Cognard type V, during transvenous attempt. A 39-year-old woman experienced mild proptosis, redness of the left eye, and diplopia. Four months later, she developed left retro-orbital pain and left-sided headache. Cerebral angiography revealed the left CSDAVF exclusively draining into the superior petrosal sinus with subsequent drainage into the veins surrounding the medulla oblongata, and finally into the perimedullary spinal veins, classified as Cognard type V. The feeders arise from the dural branches of both the left external and internal carotid arteries. Following 2 h period of attempted transvenous embolization, the fistula disappeared spontaneously. Follow-up angiography obtained 6 months later confirmed complete resolution of the CSDAVF. At 2-year follow-up, the patient has remained clinically asymptomatic. The mechanism of thrombosis in this fistula related to the endovascular procedure. We speculated that putting the wire tip in the draining vein may induce the spontaneous thrombosis in the venous side. In addition, precipitating factors may include small, low-flow fistula, and pre-existing thrombosis.

Spontaneous closure of a dural arteriovenous fistula immediately after cerebral angiography using a gadolinium contrast agent

Gadolinium (Gd) contrast agents have been used instead of iodinated contrast agents in patients in whom iodine is contraindicated, but cerebral angiography of a dural arteriovenous fistula (dAVF) using a Gd contrast agent has not previously been reported. We recently performed cerebral angiography using a Gd contrast agent in a patient with an anterior condylar confluence dAVF who was allergic to iodine. To our surprise, there was spontaneous closure of the dAVF immediately after angiography. We now report what we believe is the first such case report.

Spontaneous closure of a dural arteriovenous fistula

Spontaneous closure of a dural arteriovenous fistula (dAVF) is a rare condition and only a few cases have been reported since its first description in 1976. We report delayed and progressive spontaneous closure of a dAVF after massive intracerebral hemorrhage documented by angiographic studies before and after bleeding. To our knowledge, this is the first report to document gradual closure of a dAVF by serial angiographic studies. The mechanism of spontaneous closure of dAVFs has not been fully elucidated. We suggest different factors for consideration from previously published data and show how each of these factors can influence the others.

Spontaneous closure of intracranial dural arteriovenous fistulas: a report of 3 cases

Spontaneous closures of dural arteriovenous fistulas (dAVFs) are rare. We present spontaneous occlusion of dAVFs in 3 cases (one type IIa dAVF, one type IIb and one type III). Patients were 3 males with a mean age of 55 years (range 45-61). For two patients, the dAVF was revealed by hemorrhage. No head trauma was recorded at the interrogatory. Mean delay for spontaneous closure was 4 months (3-5 months). Review of the literature about this rare occurrence is presented and the factors that may lead to spontaneous occlusion of dAVFs are discussed.