Classification schemes of cranial dural arteriovenous fistulas

Arteriovenous shunts of the cervical spine: patient demographics, presentation, patterns of high-risk venous drainage, and updated classification

BACKGROUND

Intracranial dural arteriovenous (AV) fistula classifications focus on presence/absence of retrograde flow in the cortical veins of the brain as this angiographic finding portends a worse prognosis. However, prior categorization systems of AV shunts in the spine do not incorporate these features. We propose an updated classification for spinal shunting lesions that terms any shunting lesion with retrograde flow in any cortical vein of the brain or spinal cord medullary vein as "high risk". To present this classification, we analyzed our center's most recent experience with cervical spine shunting lesions.

METHODS

The electronic medical record at our institution was reviewed to identify shunting lesions of the cervical spine and patient demographics/presentation. Comprehensive craniospinal digital subtraction angiograms were evaluated to classify shunt location, type (arteriovenous malformation (AVM) vs arteriovenous fistula (AVF)), and presence of high-risk venous drainage.

RESULTS

Some 52 lesions were identified and categorized as pial/dural/epidural/paravertebral AVFs and intramedullary/extraspinal AVMs. Lesions were classified as high risk or not depending on the presence of retrograde flow into at least one vein that directly drains the spinal cord or brain. All patients who presented with either hemorrhage or infarct had underlying high-risk lesions. Additionally, 50% (17/34) of symptomatic patients with high-risk lesions presented with neurological extremity symptoms (OR=10.0, p=0.037) most of which fit a myelopathic pattern.

CONCLUSION

We present an updated classification system for shunting lesions of the spine that focuses on high-risk retrograde flow to the brain or spine in addition to anatomical location in order to better inform patient management.

Endovascular treatment strategy and clinical outcome of tentorial dural arteriovenous fistula

Introduction

To evaluate treatment strategies and clinical outcomes following endovascular embolization of tentorial dural arteriovenous fistulas.

Methods

We retrospectively analyzed 19 patients with tentorial dural arteriovenous fistulas admitted to the Department of Neurosurgery at Jiangsu Provincial People's Hospital between October 2015 and May 2022, all treated with endovascular therapy. To collect and analyze patients' clinical presentation, imaging data, postoperative complications, and prognosis and to analyze the safety and clinical outcomes of endovascular treatment of tentorial dural arteriovenous fistulas.

Results

Imaging cure was achieved in 18 patients, with the arterial route chosen for embolization in 17 patients and the venous route in one patient; one patient received partial embolization. Staged embolization was performed in four patients. At postoperative follow-up of 9-83 months (37.8 ± 21.2), all 19 patients had recovered well (mRS score ≤ 2). Three patients experienced perioperative complications: intraoperative Onyx reflux into the middle cerebral artery in one patient; postoperative permanent limited left visual field loss and deafness in the left ear in one patient; and transient diplopia, vertigo, and decreased pain and temperature sensation of the left limb in one patient, with no abnormalities on post-procedure magnetic resonance examinations. A total of 17 patients completed a postoperative digital subtraction angiography review during follow-up, and one patient had a recurrence of an arteriovenous fistula.

Conclusion

Endovascular treatment of tentorial dural arteriovenous fistulas is safe and effective. Reduction of the Borden or Cognard classification via eliminating cortical venous reflux through multi-staged embolization or combined open surgery is a reasonable goal of treatment where complete obliteration of the fistula is not achievable.

Characteristics and outcomes of pediatric dural arteriovenous fistulas: a systematic review

BACKGROUND

Dural arteriovenous fistulas (dAVF) are arteriovenous shunts in communication with the dural vasculature in the brain or spine. Apart from single-center series, risk factors and treatment outcomes for pediatric dAVFs are largely undescribed.

METHODS

We performed a systematic literature review of pediatric (< 18 years at diagnosis) intracranial and spinal dAVF according to PRISMA guidelines. We queried PubMed, CINAHL, SCOPUS, and Embase databases without time/date restriction. Search strings included a variety of MeSH keywords relating to dural AV fistulas in combination with MeSH keywords related to pediatric cases (see Appendix). Manuscripts describing patients diagnosed with dural sinus malformations or pial AVF were excluded.

RESULTS

We identified 61 studies describing 69 individual patients. Overall, dAVF were more common in males (55.1%) with a mean age of diagnosis (5.17 ± 4.42 years). Approximately 20.2% of patients presented with cardiovascular disease (CVD), and 31.9% were discovered incidentally on neuroimaging studies. Transverse-sigmoid junction was the most common location (17.3%). Ninety-three percent (64 patients) were treated, most commonly using endovascular embolization (68.1%) followed by surgery (8.7%) and radiosurgery (2.9%). Almost half (43.8%) of dAVFs were completely obliterated. Of the 64 procedures, there were 19 neurological complications (29.7%) of varying severity where 12.5% were considered transient (i.e., pseudomeningocele) and 17.2% permanent (i.e., mortality secondary to acute sinus thrombosis, etc.).

CONCLUSION

There is a paucity of information on pediatric dAVFs. This systematic review summarizes the published cases of dAVFs in the pediatric population. While the rate of missing data is high, there is publication bias, and precise details regarding complications are difficult to ascertain, this review serves as a descriptive summary of pediatric dAVFs.

A falcotentorial dural arteriovenous fistula presented as carotid cavernous fistula clinically treated by transarterial embolization: case report

Background

Dural arteriovenous fistulas (DAVF) represent almost 10–15% of intracranial malformations that cause intracranial hemorrhage and focal neurological deficits. Seldom tentorial DAVF cases present with ocular manifestations initially, which occur frequently in carotid–cavernous fistula (CCF) and cavernous sinus DAVF (CS DAVF).

Case presentation

We report an unusual falcotentorial DAVF case draining via the superior and inferior ophthalmic veins that caused left-side increased intraocular pressure. The patient’s chief complaint was swelling on the left side, pain and conjunctival congestion. He received endovascular embolization via a transarterial approach, and postoperative angiography demonstrated that the falcotentorial DAVF was occluded completely.

Conclusion

Except for CCF and CS DAVF, some specific subtypes of DAVF should be considered if the patient initially presents with ocular symptoms. Differential diagnosis and definitive treatment are mandatory to avoid a delayed diagnosis and irreversible symptoms.

Validation of SART 3.5D algorithm for cerebrovascular dynamics and artery versus vein classification in presurgical 3D digital subtraction angiographies

Classification of arteries and veins in cerebral angiograms can increase the safety of neurosurgical procedures, such as StereoElectroEncephaloGraphy, and aid the diagnosis of vascular pathologies, as arterovenous malformations. We propose a new method for vessel classification using the contrast medium dynamics in rotational digital subtraction angiography (DSA). After 3D DSA and angiogram segmentation, contrast enhanced projections are processed to suppress soft tissue and bone structures attenuation effect and further enhance the CM flow. For each voxel labelled as vessel, a time intensity curve (TIC) is obtained as a linear combination of temporal basis functions whose weights are addressed by simultaneous algebraic reconstruction technique (SART 3.5D), expanded to include dynamics. Each TIC is classified by comparing the areas under the curve in the arterial and venous phases. Clustering is applied to optimize the classification thresholds. On a dataset of 60 patients, a median value of sensitivity (90%), specificity (91%), and accuracy (92%) were obtained with respect to annotated arterial and venous voxels up to branching order 4–5. Qualitative results are also presented about CM arrival time mapping and its distribution in arteries and veins respectively. In conclusion, this study shows a valuable impact, at no protocol extra-cost or invasiveness, concerning surgical planning related to the enhancement of arteries as major organs at risk. Also, it opens a new scope on the pathophysiology of cerebrovascular dynamics and its anatomical relationships.

Transorbital hybrid approach for endovascular occlusion of indirect carotid-cavernous fistulas–Case report and systematic literature review

Carotid-cavernous fistulas (CCF) are vascular malformations characterized by an aberrant shunt between one or more sources of arterial inflow and the cavernous sinus (CS). They are subdivided into direct and indirect fistulas. This last one, called dural CCF involve dural fistulous connections between branches of the internal carotid artery or the external carotid artery. When conventional routes are not eligible, surgical exposure of the vein is the only access to the fistula. We present the case of a patient successfully treated for right sided dural CCF, by a hybrid approach. Furthermore, through a literature review, we analyze the possible risks and benefits associated with this approach.

Digital subtraction angiography in cerebrovascular disease: current practice and perspectives on diagnosis, acute treatment and prognosis

Digital Subtraction Angiography (DSA) is the gold-standard imaging modality in acute cerebrovascular diagnosis. The role of DSA has become increasingly prominent since the incorporation of endovascular therapy in standards of care for acute ischemic stroke. It is used in the assessment of cerebral vessel patency; however, the therapeutic role of DSA from a prognostic standpoint merits further investigation. The current paper provides an update on current practice on diagnostic, therapeutic and prognostic use of DSA in acute cerebrovascular diseases and various indications and perspectives that may apply, or limit its use, in ongoing surveillance or prognosis. Pre-clinical and clinical studies on the aspects, including but not limited to the morphology of cerebrovasculature in acute ischaemic stroke, are required to delineate and inform its prognostic role.

Foramen Caecum Vein Involved in Dural Arteriovenous Fistula Fed by Sphenopalatine Arteries: A Case Report

Anterior cranial fossa (ACF) dural arteriovenous fistulas (ACF DAVFs) are an infrequent subtype of cranial DAVFs that are usually fed by the anterior ethmoidal artery (AEA) and ophthalmic artery (OA) branches. Due to the lack of dural venous sinus in the ACF, they directly drain into cortical veins, resulting in high bleeding tendency. For this reason, ACF DAVFs have to be treated regardless of whether they are symptomatic or not. A 74-year-old man, with hypertension history, came to our attention because of ear pain, dizziness, and impaired hearing for 2 months. No other pathological conditions have been found in his medical history. The patient underwent brain magnetic resonance imaging (MRI) scan and subsequently second level diagnostic investigations with digital subtraction angiography (DSA), showing a foramen caecum (FC) patency and a persistent, enlarged, arterialized FC vein (FCV) involved in an incidental ACF DAVF (Cognard IV), fed mainly by sphenopalatine arteries (SPAs) branches bilaterally. The patient underwent open surgery performed by small high frontal craniotomy with DAVFs complete closure and without any complications. To the best of our knowledge, this is the first case ever described of FCV persistence with involvement in an intracranial vascular malformation. It has been managed by surgical intervention that can be considered, despite the large skin incision, a minimally invasive approach with an excellent cosmetic result and minimal risk of complications.

Prevalence of Tinnitus in Patients Diagnosed with Cerebral Arteriovenous Fistula Treated with Endovascular Technique

Introduction  Tinnitus is characterized as the conscious and involuntary perception of sound, and it affects ∼ 30% of the population. Despite careful physical examination, the etiology of tinnitus can be established for only 30% of patients. Tinnitus is a common symptom of cerebral arteriovenous fistulas and results from increased blood flow through the dural venous sinuses, leading to turbulent arterial flow, mainly related to sigmoid and transverse sinus lesions.

Objectives  To analyze the frequency of tinnitus, patient profile, and endovascular treatment characteristics in individuals diagnosed with cerebral arteriovenous fistulas.

Methods  A retrospective and observational study based on reviewed data from medical records on the PHILIPS Tasy system (Philips Healthcare, Cambridge, MA, USA) at the neurosurgery and interventional neuroradiology service of Hospital Santa Isabel in Blumenau–state of Santa Catarina, Brazil.

Results  The profile of 68 individuals diagnosed with cerebral arteriovenous fistula who underwent endovascular treatment were analyzed. Most patients were female, aged 31 to 60. Tinnitus affected 18 individuals. Dural fistulas were the most prevalent in the sample, and computed tomography alone was the most used diagnostic method for initial investigation.

Conclusion  The prevalence of this symptom in patients diagnosed with cerebral arteriovenous fistula was found in 26.5% of this sample, mainly in women with associated comorbidities. Tinnitus remission was observed in all patients who underwent endovascular treatment to correct cerebral fistula.

Conventional and advanced MRI evaluation of brain vascular malformations

Vascular malformations (VMs) of the central nervous system (CNS) include a wide range of pathological conditions related to intra and extracranial vessel abnormalities. Although some VMs show typical neuroimaging features, other VMs share and overlap pathological and neuroimaging features that hinder an accurate differentiation between them. Hence, it is not uncommon to misclassify different types of VMs under the general heading of arteriovenous malformations. Thorough knowledge of the imaging findings of each type of VM is mandatory to avoid these inaccuracies. Conventional MRI sequences, including MR angiography, have allowed the evaluation of CNS VMs without using ionizing radiation. Newer MRI techniques, such as susceptibility-weighted imaging, black blood sequences, arterial spin labeling, and 4D flow imaging, have an added value of providing physiopathological data in real time regarding the hemodynamics of VMs. Beyond MR images, new insights using 3D printed models are being incorporated as part of the armamentarium for a noninvasive evaluation of VMs. In this paper, we briefly review the pathophysiology of CNS VMs, focusing on the MRI findings that may be helpful to differentiate them. We discuss the role of each conventional and advanced MRI sequence for VMs assessment and provide some insights about the value of structured reports of 3D printing to evaluate VMs.

Changes in Angioarchitecture After Stereotactic Radiosurgery for Dural Arteriovenous Fistula

INTRODUCTION

Dural arteriovenous fistulae (DAVF) are intracranial vascular abnormalities encountered in neurosurgery practice. Treatment options are microsurgical disconnection, endovascular embolization and/or radiosurgery. Past studies have reported the efficacy, safety, and predictors of success of radiosurgery. In this study, we investigated the angioarchitecture of fistulae at the time of radiosurgery and how the anatomy changed in the time after treatment based on angiogram follow-ups.

METHODS

A retrospective analysis was performed on patients with angiographic diagnosis of DAVF treated with Gamma Knife radiosurgery (GKRS) between 2013 and 2018. Data collection included demographics, symptoms, grading scores, vascular anatomy, radiation data, treatment strategy, angiographic results, and length of patient follow-up.

RESULTS

Our study reports data on 10 patients with a total of 14 fistulae. On follow-up angiography, 8 (57%) had complete occlusion of the fistula with a median time to follow up of 19.5 months. The remaining 6 (43%) were deemed as near-complete occlusion of fistula with a median time to follow up of 12.0 months. Time from radiosurgery to angiogram revealing incomplete vs. angiogram revealing complete obliteration was significantly different (p=0.045). Nearly all AVFs had decreased feeders over time after treatment with only one AVF developing an additional feeder post-treatment. Arterial feeders, drainage site, sex, Borden type, lesion volume and treatment volume had no predictive value of obliteration outcome.

CONCLUSIONS

This study provides data on the angioarchitecture of fistulae treated with GKRS and also serves as an extension of previous studies reporting the safety and efficacy of GKRS treatment for DAVF in a specific patient population.

Long-term follow-up of transarterial balloon-assisted Onyx embolization for endovascular treatment of dural arteriovenous fistulas: A single-institution case series and literature review

OBJECTIVE

Dural arteriovenous fistulas (DAVFs)-specifically, symptomatic DAVFs with cortical venous reflux-are aggressive lesions with a poor prognosis. Intra-arterial endovascular closure is considered the optional treatment for DAVFs and is currently performed at several international centers. However, long-term outcomes remain unknown. This study investigated the long-term efficacy and safety of transarterial balloon-assisted Onyx embolization in the treatment of DAVFs.

METHODS

A total of 14 consecutive patients who underwent endovascular treatment for DAVFs were treated by balloon-assisted Onyx embolization. Additionally, we retrospectively reviewed all cases reported in the literature and compared the outcomes of patients treated with single- vs dual-lumen microcatheters.

RESULTS

The patients at our institution were followed-up for 114.57 ± 33.52 months. Embolization was performed by balloon-assisted Onyx injection via a single feeding artery. Complete occlusion was achieved in 13 cases and partial occlusion in 1 case. At the final follow-up, all patients were functionally independent (Modified Rankin Scale score of 0-2), with no recurrence. In our review of 70 published cases of DAVFs that underwent endovascular treatment by balloon-assisted Onyx embolization, single- and dual-lumen balloon catheters were used in 33 and 37 patients, respectively. In the former group, there was complete or near-complete occlusion in 32 cases and partial occlusion in 1 case; and in the latter, there was complete or near-complete occlusion in 35 cases and partial occlusion in 2 cases. There were no deaths following endovascular treatment.

CONCLUSION

Measurable and durable outcomes can be achieved by endovascular treatment of DAVFs with the transarterial balloon-assisted Onyx embolization technique, especially in cases with small, distal, and circuitous feeding arteries.

A new subtype of intracranial dural AVF according to the patterns of venous drainage

BACKGROUND AND PURPOSE

A well-known classification of dural arteriovenous fistulas (DAVFs) according to the patterns of venous drainage was described in 1977 by Djindjian, Merland et al. and later revised by Cognard, Merland et al. in 1995. They described 5 types of DAVFs assuming that the type of venous drainage is directly correlated with neurologic symptoms and in particular with hemorrhagic risk. We present a series of cases that combines type IV (DAVF with cortical venous drainage associated with venous ectasia) and type V (DAVF with spinal venous drainage), which we named type IV + V.

MATERIALS AND METHODS

A retrospective study between 2012 and 2020 in 2 Hospitals was performed on patients that met inclusion criteria for a diagnosis of this type of DAVF. Demographics, location, clinical presentation and outcomes of endovascular embolization were studied.

RESULTS

Five (2,3%) patients out of 220 had a type IV + V DAVF. All cases had an aggressive presentation, either subarachnoid hemorrhage, myelopathy or both. All patients were treated with endovascular transarterial embolization achieving complete angiographic occlusion in one session and total remission of symptoms at 3 months.

CONCLUSIONS

This rare type of DAVF, combines two aggressive venous drainage patterns. For that reason, patients with type IV+V DAVF probably have a more aggressive natural history and worst outcome due to risk of intracranial and/or spinal hemorrhage and myelopathy, thus requiring urgent diagnostic and treatment. Larger studies are needed to better understand this type of DAVF.

Cognard Grade IV Tentorial Dural Arteriovenous Fistula Presenting as Trigeminal Neuralgia: Endovascular Management

Tentorial dural arteriovenous fistulas have an increased risk of rupture and hemorrhage, and therefore require urgent treatment to occlude the fistula and proximal venous drainage. This is usually accomplished via endovascular treatment. We present a case of a Cognard grade IV dural arteriovenous fistula that presented as trigeminal neuralgia. This video showcases the angiographic vascular composition of the lesion with main feeders coming from the middle meningeal artery and the tentorial artery of Bernasconi and Cassinari. Details, benefits, and risks of the procedure were thoroughly discussed with the patient and consent was obtained prior to the procedure. We performed endovascular Onyx embolization through a distal branch of the right middle meningeal artery. We were able to successfully occlude the lesion using Onyx embolization and the patient had significant improvement of her pretreatment trigeminal neuralgia.

Myelopathy Due to Intracranial Dural Arteriovenous Fistula with Perimedullary Venous Drainage: Clinical and Medicolegal Aspects in a Case of Diagnostic Pitfall

BACKGROUND

Intracranial dural arteriovenous fistula (DAVF) consists of a meshwork of arteriovenous shunts. Drainage of the fistula may be into a dural sinus or directly into cortical veins. Rarely, dural arteriovenous fistulas drain exclusively into perimedullary veins. Prompt diagnosis is important, as the clinical course is potentially life threatening.

CASE DESCRIPTION

A 67-year-old man presented with difficulties in walking and bladder retention. Magnetic resonance imaging showed central myelopathy, edema from C6 to T8, and dilated posterior medullary veins. Spinal angiography showed no abnormalities. The diagnostic impression was one of inflammatory demyelinating disease, and the patient was treated with corticosteroids. Three days later, the patient had become paraparetic. Brain magnetic resonance imaging showed abnormal vascular structures around the lower brainstem and cervical cord. Cerebral angiography showed a dural fistula at the skull base supplied by the neuromeningeal branch of the ascending pharyngeal artery and draining into the posterior medullary veins. Following neurosurgical referral, the draining vein was clipped just beyond the arterial feeders. At that time, the patient was wheelchair-bound and needed assistance in daily activities.

CONCLUSIONS

Early diagnosis of this rare vascular malformation is challenging; angiographic studies must include the cranial vasculature when spinal studies are normal or if the abnormality on magnetic resonance imaging is maximal in the upper spinal cord. In the case described, as only medullary angiography was performed, the intracranial dural arteriovenous fistula with perimedullary venous drainage was not diagnosed. Delayed diagnosis is likely to lead to severe neurologic consequences.

Embryological Consideration of Dural AVFs in Relation to the Neural Crest and the Mesoderm

Intracranial and spinal dural arteriovenous fistulas (DAVFs) are vascular pathologies of the dural membrane with arteriovenous shunts. They are abnormal communications between arteries and veins or dural venous sinuses that sit between the two sheets of the dura mater. The dura propria faces the surface of brain, and the osteal dura faces the bone. The location of the shunt points is not distributed homogeneously on the surface of the dural membrane, but there are certain areas susceptible to DAVFs. The dura mater of the olfactory groove, falx cerebri, inferior sagittal sinus, tentorium cerebelli, and falx cerebelli, and the dura mater at the level of the spinal cord are composed only of dura propria, and these areas are derived from neural crest cells. The dura mater of the cavernous sinus, transverse sinus, sigmoid sinus, and anterior condylar confluence surrounding the hypoglossal canal are composed of both dura propria and osteal dura; this group is derived from mesoderm. Although the cause of this heterogeneity has not yet been determined, there are some specific characteristics and tendencies in terms of the embryological features. The possible reasons for the segmental susceptibility to DAVFs are summarized based on the embryology of the dura mater.

Current status of endovascular treatment for dural arteriovenous fistulae in the tentorial middle region: a literature review

The tentorial middle region (TMR) includes the midline and paramedian tentorium. TMR dural arteriovenous fistulae (DAVFs) are complex. We performed a review of the literature on TMR DAVFs. TMR DAVFs are divided into the following four types: incisural DAVF, Galenic DAVF, straight sinus DAVF and torcular DAVF. TMR DAVFs often drain into pial veins; therefore, most TMR DAVFs are classified as Borden II-III and Cognard types IIb-IV, whose characteristics cause TMR DAVFs to be prone to hemorrhage. TMR DAVFs have a very disappointing natural progression, and treatment is necessary. TMR DAVFs have extensive arterial supply and complex venous drainages, making them difficult to treat. Currently, for TMR DAVF, endovascular treatment (EVT) has become a better option. In EVT, transarterial embolization is the first-line treatment. Many complications can occur when treating TMR DAVFs, but complete EVT can generally achieve good clinical outcomes. In this review, three educational cases with demonstrating figures are provided to elaborate TMR DAVFs.

Evaluation of stereotactic radiosurgery for cerebral dural arteriovenous fistulas in a multicenter international consortium

OBJECTIVE

In this multicenter study, the authors reviewed the results obtained in patients who underwent Gamma Knife radiosurgery (GKRS) for dural arteriovenous fistulas (dAVFs) and determined predictors of outcome.

METHODS

Data from a cohort of 114 patients who underwent GKRS for cerebral dAVFs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as dAVF obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and dAVF characteristics were assessed to determine predictors of outcome in a multivariate logistic regression analysis; dAVF-free obliteration was calculated in a competing-risk survival analysis; and Youden indices were used to determine optimal radiosurgical dose.

RESULTS

A mean margin dose of 21.8 Gy was delivered. The mean follow-up duration was 4 years (range 0.5-18 years). The overall obliteration rate was 68.4%. The postradiosurgery actuarial rates of obliteration at 3, 5, 7, and 10 years were 41.3%, 61.1%, 70.1%, and 82.0%, respectively. Post-GRKS hemorrhage occurred in 4 patients (annual risk of 0.9%). Radiation-induced imaging changes occurred in 10.4% of patients; 5.2% were symptomatic, and 3.5% had permanent deficits. Favorable outcome was achieved in 63.2% of patients. Patients with middle fossa and tentorial dAVFs (OR 2.4, p = 0.048) and those receiving a margin dose greater than 23 Gy (OR 2.6, p = 0.030) were less likely to achieve a favorable outcome. Commonly used grading scales (e.g., Borden and Cognard) were not predictive of outcome. Female sex (OR 1.7, p = 0.03), absent venous ectasia (OR 3.4, p < 0.001), and cavernous carotid location (OR 2.1, p = 0.019) were predictors of GKRS-induced dAVF obliteration.

CONCLUSIONS

GKRS for cerebral dAVFs achieved obliteration and avoided permanent complications in the majority of patients. Those with cavernous carotid location and no venous ectasia were more likely to have fistula obliteration following radiosurgery. Commonly used grading scales were not reliable predictors of outcome following radiosurgery.

Current status of endovascular treatment for dural arteriovenous fistulae in the anterior cranial fossa: A systematic literature review

Anterior cranial fossa (ACF) dural arteriovenous fistulae (DAVFs) are rare, and a systematic review of the literature is lacking. Such a review is necessary, however, so a systematic PubMed search of related studies was performed. Twenty-four studies were identified, reporting on 48 patients, of whom 39 had definite age and sex information and 33 (84.6%, 33/39) were male. The afflicted patients were between 37 and 80 years old (mean 55.6). Among the 48 patients, 28 (58.3%, 28/48) primarily presented with intracranial hemorrhage, 47 (97.9%, 47/48) had feeding arteries from the anterior ethmoidal artery (AEA) of the ophthalmic artery (OA), and 40 (83.3%, 40/48) had bilateral feeding arteries. All of the cases had high-grade Cognard classifications (III-IV). Among the 48 patients, 43 (89.6%, 43/48) had drainage into the superior sagittal sinus (SSS). In addition, 36 (75%, 36/48) patients were treated via transarterial embolization (TAE). Of these patients, 28 (77.8%, 28/36) were managed via the AEA of the OA. Another 12 (25%, 12/48) patients were treated via transvenous embolization (TVE), 11 of whom (91.7%, 11/12) were treated with the trans-SSS approach. Complete angiographic cure was achieved in 44 (91.7%, 44/48) patients, with 4 (8.3%, 4/48) patients suffering from postprocedural complications. All 48 patients had clear descriptions of follow-up outcomes, with 45 (93.8%, 45/48) patients having a good outcome. Thus, when treating ACF DAVFs, endovascular treatment (EVT) can completely obliterate the fistula point and correct the venous shunting. EVT is therefore an effective treatment for ACF DAVF. Although many complications can occur, this approach achieves good outcomes in most cases.

Ruptured Dural Arteriovenous Fistula/Malformation

When "common things are common," the discovery of a subdural hemorrhage in an adult is most likely to be due to trauma. When the subdural hemorrhage is associated with an intraparenchymal hematoma, statistically speaking, the subdural hemorrhage is likely the result of a hypertensive hemorrhage that has ruptured into the subdural space or trauma that resulted from a collapse to the ground following hypertensive intra-axial bleeding. However, "common things" do not always explain the source of a subdural hemorrhage or intraparenchymal hematoma. In this case, an adult woman presented to the hospital obtunded and was diagnosed with a subdural hemorrhage (with mass effect) and intraparenchymal hematoma as the result of a ruptured dural arteriovenous fistula/malformation. This case highlights an unusual source of intracranial bleeding that resulted in death.

Contemporary Imaging of Cerebral Arteriovenous Malformations

OBJECTIVE

Brain arteriovenous malformation (AVM) rupture results in substantial morbidity and mortality. The goal of AVM treatment is eradication of the AVM, but the risk of treatment must be weighed against the risk of future hemorrhage.

CONCLUSION

Imaging plays a vital role by providing the information necessary for AVM management. Here, we discuss the background, natural history, clinical presentation, and imaging of AVMs. In addition, we explain advances in techniques for imaging AVMs.

Therapeutic progress in pediatric intracranial dural arteriovenous shunts: A review

Pediatric dural arteriovenous shunts (dAVSs) are a rare form of vascular disease: Fewer than 100 cases are reported in PubMed and the understanding of pediatric dAVS is limited. For this study, we searched in PubMed, reviewed and summarized the literature related to pediatric dAVSs. Our review revealed that pediatric dAVSs have an unfavorable natural history: If left untreated, the majority of pediatric dAVSs deteriorate. In a widely accepted classification scheme developed by Lasjaunias et al., pediatric dAVSs are divided into three types: Dural sinus malformation (DMS) with dAVS, infantile dAVS (IDAVS) and adult-type dAVS (ADAVS). In general, the clinical manifestations of dAVS can be summarized as having symptoms due to high-flow arteriovenous shunts, symptoms from retrograde venous drainage, symptoms from cavernous sinus involvement and hydrocephalus, among other signs and symptoms. The pediatric dAVSs may be identified with several imaging techniques; however, the gold standard is digital subtraction angiography (DSA), which indicates unique anatomical details and hemodynamic features. Effectively treating pediatric dAVS is difficult and the prognosis is often unsatisfactory. Transarterial embolization with liquid embolic agents and coils is the treatment of choice for the safe stabilization and/or improvement of the symptoms of pediatric dAVS. In some cases, transumbilical arterial and transvenous approaches have been effective, and surgical resection is also an effective alternative in some cases. Nevertheless, pediatric dAVS can have an unsatisfactory prognosis, even when timely and appropriate treatment is administered; however, with the development of embolization materials and techniques, the potential for improved treatments and prognoses is increasing.

De novo formation of cerebral cavernous malformation adjacent to existing developmental venous anomaly - an effect of change in venous pressure associated with management of a complex dural arterio-venous fistula

This is a case report of de novo development of two cerebral cavernous malformations adjacent to existing developmental venous anomalies. The development of cavernomas was noted over a follow-up period of 10 years. These developments happened during the course of staged endovascular management of a complex dural arterio-venous fistula along the right sphenoid wing. The patient presented with a proptosis secondary to lympho-haemangiomatous lesion of the fronto-orbital region and a high-flow right sphenoid wing dural arterio-venous fistula. During the initial period of conservative management of the dural arterio-venous fistula, he developed de novo cavernous malformations in the left mesial temporal lobe adjacent to a developmental venous anomaly in the temporal lobe, and along with this there was engorgement of deep veins related to another existing developmental venous anomaly in the brainstem. Later during the course of endovascular treatment of the dural arterio-venous fistula, a large brainstem cavernoma developed adjacent to the brainstem developmental venous anomaly. This case report discusses the cause-effect relationship of venous pressure changes related to management of dural arterio-venous fistula and de novo formation of cerebral cavernous malformations adjacent to existing developmental venous anomalies.

Angioarchitectural evolution of clival dural arteriovenous fistulas in two patients

Dural arteriovenous fistulas (dAVFs) may present in a variety of ways, including as carotid-cavernous sinus fistulas. The ophthalmologic sequelae of carotid-cavernous sinus fistulas are known and recognizable, but less commonly seen is the rare clival fistula. Clival dAVFs may have a variety of potential anatomical configurations but are defined by the involvement of the venous plexus just overlying the bony clivus. Here we present two cases of clival dAVFs that most likely evolved from carotid-cavernous sinus fistulas.

Non-contrast-enhanced 4D MR angiography with STAR spin labeling and variable flip angle sampling: a feasibility study for the assessment of Dural Arteriovenous Fistula

INTRODUCTION

This study aimed to evaluate the feasibility of non-contrast-enhanced 4D magnetic resonance angiography (NCE 4D MRA) with signal targeting with alternative radiofrequency (STAR) spin labeling and variable flip angle (VFA) sampling in the assessment of dural arteriovenous fistula (DAVF) in the transverse sinus.

METHODS

Nine patients underwent NCE 4D MRA for the evaluation of DAVF in the transverse sinus at 3 T. One patient was examined twice, once before and once after the interventional treatment. All patients also underwent digital subtraction angiography (DSA) and/or contrast-enhanced magnetic resonance angiography (CEMRA). For the acquisition of NCE 4D MRA, a STAR spin tagging method was used, and a VFA sampling was applied in the data readout module instead of a constant flip angle. Two readers evaluated the NCE 4D MRA data for the diagnosis of DAVF and its type with consensus. The results were compared with those from DSA and/or CEMRA.

RESULTS

All patients underwent NCE 4D MRA without any difficulty. Among seven patients with patent DAVFs, all cases showed an early visualization of the transverse sinus on NCE 4D MRA. Except for one case, the type of DAVF of NCE 4D MRA was agreed with that of reference standard study. Cortical venous reflux (CVR) was demonstrated in two cases out of three patients with CVR.

CONCLUSION

NCE 4D MRA with STAR tagging and VFA sampling is technically and clinically feasible and represents a promising technique for assessment of DAVF in the transverse sinus. Further technical developments should aim at improvements of spatial and temporal coverage.