Management of tentorial dural arteriovenous malformations: transarterial embolization combined with stereotactic radiation or surgery

Secondary ocular hypertension due to tentorial dural arteriovenous fistula: a case report

BACKGROUND

Tentorial dural arteriovenous fistulas (TDAVFs) are abnormal shunts between meningeal arteries and the intradural venous system located in the tentorial dura mater, which typically manifest with haemorrhage or progressive neurological disorders. TDAVFs with pure ocular presentation have been rarely reported.

CASE PRESENTATIONS

The case of a 56-year-old man presented with unilateral eye redness, proptosis and elevated intraocular pressure was reported herein, which was caused by a TDAVF. The fistula was fed by the left posterior cerebral artery and posterior meningeal artery. The drainage was into the basal vein and internal cerebral veins, which led the arterial blood flow forward to the left superior ophthalmic vein directly. The redundant blood flow caused the rise of episcleral venous pressure, leading to the clinical presentations. Gamma knife radiosurgery was performed then considering the delicate vascular structure and its deep location. The corkscrew hyperaemia was gradually alleviated after the surgery, but the intraocular pressure remained elevated at follow-ups.

CONCLUSION

Dural arteriovenous fistulas which are not directly connected to cavernous sinus could cause ocular presentations like proptosis, eye redness and ocular hypertension.

A retrospective study of 78 adult tentorial middle line region dural arteriovenous fistulae

OBJECTIVE

Dural arteriovenous fistulae (DAVF) in the tentorial middle line region are uncommon with specific features and more cognitive disorders than any other region. The purpose of this study is to present clinical characteristics and our experience with endovascular treatment in this specific region.

METHODS

During a 20-year period, 94.9% of patients (74/78) underwent endovascular treatment (36 in galenic, 48.6%) (12 in straight sinus, 16.2%) (26 in torcular, 35.1%). There were 63 males and 15 females with mean age of 50 (50 ± 12) years in total of 78 patients. The clinical presentation, angiographic features, treatment strategy, and clinical outcomes were recorded.

RESULTS

Transarterial embolization (TAE) was performed in 89.2% of the 74 patients (66/74), transvenous embolization alone in one patient and mixed approach in seven. Complete obliteration of the fistulas was obtained in 87.5% of the patients (64/74). 71 patients (mean, 56 months) had phone, outpatient, or admission follow-up. The digital subtraction angiography (DSA) follow-up period (25/78, 32.1%) was 13.8 (6-21) months. Two of them (2/25, 8%) had fistula recurrences after complete embolization and were embolized again. The phone follow-up period (70/78, 89.7%) was 76.6 (40-92.3) months. Pre-embolization and post-embolization mRS ≥ 2 were in 44 patients (44/78) and 15 (15/71) patients, respectively. DAVF with internal cerebral vein drainage (OR 6.514, 95% Cl 1.201-35.317) and intracranial hemorrhage (OR 17.034, 95% Cl 1.122-258.612) during TAE were the risk factors for predicting poor outcomes (followed up mRS ≥ 2).

CONCLUSIONS

TAE is the first-line treatment for tentorial middle line region DAVF. When pial feeders' obliteration is difficult to achieve, it should not be forced due to the poor outcomes after intracranial hemorrhage. The cognitive disorders caused by this region were not reversible as reported. It is imperative to enhance the care provided to these patients with cognitive disorders.

Petrous apex's dural arteriovenous fistula (DAVF) mimicking a pineal region tumour: a rare cause of Hakim triad

A dural arteriovenous fistula (DAVF) is a dural-based shunt between meningeal arteries and meningeal veins, sinuses and/or cortical veins; they have been classified and named according to the location and the flow pattern. Petrous apex DAVFs are located where the petrosal vein penetrates the dura mater into the superior petrosal sinus; there are only few cases reported in the literature, they can show an aggressive behaviour (subarachnoid haemorrhage, severe brainstem oedema) with a high mortality rate. The described case is, to the best of our knowledge, the first case of a DAVF presenting with symptoms mimicking idiopathic normal pressure hydrocephalus. After worsening of gait impairment, memory loss and urinary incontinence an urgent CT of the brain showed hydrocephalus and a hyperdense mass in the pineal region mimicking a pineal tumour; an emergent digital subtraction angiogram showed a left petrous apex Borden type III DAVF. A transvenous embolisation was performed obtaining a complete obliteration.

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.

Endovascular Treatment of Hemifacial Spasm Associated with a Tentorial DAVF Using Transarterial Onyx Embolization: A Case Report

Objective

We describe a patient treated with transarterial Onyx embolization for a tentorial dural arteriovenous fistula (DAVF) who presented with hemifacial spasm (HFS).

Case Presentation

A 56-year-old man suffered from right blepharospasm for 4 years, and the symptom gradually spread to the right side of his face with oculo-oral synkinesis. MRI of the brain revealed abnormal multiple flow voids at the surface of brainstem and cerebellar hemisphere. MRA (time of flight) and spoiled gradient recalled echo-revealed abnormal vessels at the posterior fossa indicated arteriovenous shunting. 3D-MRI fusion images showed that a dilated vein was in contact with the root exit zone (REZ) of the right facial nerve. The right carotid angiography displayed a complex tentorial DAVF on the right side. There were multiple feeding vessels drained to the tentorial sinus at the point where the inferior cerebellar vermian vein met, and severe venous congestion was noted. We diagnosed a tentorial DAVF and thought that this was responsible for the right HFS. We used neuroendovascular treatment for this lesion. After transarterial Onyx embolization, his right HFS diminished. MRI after treatment showed that the vein in contact with the REZ of the right facial nerve had shrank.

Conclusion

We experienced a rare case of HFS associated with a DAVF. Our case supports that transarterial Onyx embolization can treat HFS associated with a tentorial DAVF. It is the first description of successful treatment that could be confirmed through postoperative MRI.

Stereotactic Radiosurgery for Dural Arteriovenous Fistulas: A Systematic Review and Meta-Analysis and International Stereotactic Radiosurgery Society Practice Guidelines

BACKGROUND

Dural arteriovenous fistulas (dAVFs) are often treated with stereotactic radiosurgery (SRS) to achieve complete obliteration (CO), prevent future hemorrhages, and ameliorate neurological symptoms.

OBJECTIVE

To summarize outcomes after SRS for dAVFs and propose relevant practice recommendations.

METHODS

Using a PICOS/PRISMA/MOOSE protocol, we included patients with dAVFs treated with SRS and data for at least one of the outcomes of the study. Relevant outcomes were CO, symptom improvement and cure, and post-SRS hemorrhage or permanent neurological deficits (PNDs). Estimated outcome effect sizes were determined using weighted random-effects meta-analyses using DerSimonian and Laird methods. To assess potential relationships between patient and lesion characteristics and clinical outcomes, mixed-effects weighted regression models were used.

RESULTS

Across 21 published studies, we identified 705 patients with 721 dAVFs treated with SRS. The CO rate was 68.6% (95% CI 60.7%-76.5%) with symptom improvement and cure rates of 97.2% (95% CI 93.2%-100%) and 78.8% (95% CI 69.3%-88.2%), respectively. Estimated incidences of post-SRS hemorrhage and PNDs were 1.1% (95% CI 0.6%-1.6%) and 1.3% (95% CI 0.8%-1.8%), respectively. Noncavernous sinus (NCS) dAVFs were associated with lower CO (P = .03) and symptom cure rates (P = .001). Higher grade was also associated with lower symptom cure rates (P = .04), whereas previous embolization was associated with higher symptom cure rates (P = .01).

CONCLUSION

SRS for dAVFs results in CO in the majority of patients with excellent symptom improvement rates with minimal toxicity. Patients with NCS and/or higher-grade dAVFs have poorer symptom cure rates. Combined therapy with embolization and SRS is recommended when feasible for clinically aggressive dAVFs or those refractory to embolization to maximize the likelihood of symptom cure.

Endovascular management of anterior falcotentorial dural arteriovenous fistulas: importance of functionality of deep venous system and existence of accompanying choroidal arteriovenous malformation

BACKGROUND

Anterior falcotentorial junction dural arteriovenous fistulas (AFDAVFs) are the most deeply located and most complex type of tentorial fistula due to their location and vascular anatomy. We aimed to make new angiographic definitions of AFDAVF nidus and functionality of the deep venous system of the brain and thereby provide a safer approach for endovascular treatment.

METHODS

We retrospectively examined 18 patients with AFDAVF who received endovascular treatment at our neuroradiology department between June 2002 and May 2019. Pre- and post-treatment clinical assessments were performed using the modified Rankin Scale. AFDAVF niduses were defined as mixed-type or pure-dural-type on the basis of whether choroidal arteriovenous malformation was coexisting or not, respectively. The deep venous system was denoted as functional or nonfunctional.

RESULTS

We included 13 men and 5 women (mean (range) age, 47.2 (31-62) years). We evaluated 15 patients with pure-dural-type AFDAVFs and three with mixed-type AFDAVFs. Complete occlusion of the fistula was achieved in 15/18 patients. Three patients had transient neurologic symptoms. In two patients these were due to mild thalamic ischemia and in the third patient was due to tectal venous ischemia, all in mixed-type AFDAVF. One patient also developed Parinaud syndrome due to compression of the tectal plate by a thrombosed large vein of Galen. No patients died or developed permanent morbidity.

CONCLUSION

Evaluating AFDAVFs as described here using our new subtyping model will help improve analysis of the malformation and development of a safer endovascular strategy, and hence may prevent periprocedural complications and improve treatment safety.

A Proposed Grading Scale for Predicting Outcomes After Stereotactic Radiosurgery for Dural Arteriovenous Fistulas

BACKGROUND

There are presently no grading scales that specifically address the outcomes of cranial dural arteriovenous fistula (dAVF) after stereotactic radiosurgery (SRS).

OBJECTIVE

To design a practical grading system that would predict outcomes after SRS for cranial dAVFs.

METHODS

From the International Radiosurgery Research Foundation (University of Pittsburgh [41 patients], University of Pennsylvania [6 patients], University of Sherbrooke [2 patients], University of Manitoba [1 patient], West Virginia University [2 patients], University of Puerto Rico [1 patient], Beaumont Health System 1 [patient], Na Homolce Hospital [13 patients], the University of Virginia [48 patients], and Yale University [6 patients]) centers, 120 patients with dAVF treated with SRS were included in the study. The factors predicting favorable outcome (obliteration without post-SRS hemorrhage) after SRS were assessed using logistic regression analysis. These factors were pooled with the factors that were found to be predictive of obliteration from 7 studies with 736 patients after a systematic review of literature. These were entered into stepwise multiple regression and the best-fit model was identified.

RESULTS

Based on the predictive model, 3 factors emerged to develop an SRS scoring system: cortical venous reflux (CVR), prior intracerebral hemorrhage (ICH), and noncavernous sinus location. Class I (score of 0-1 points) predicted the best favorable outcome of 80%. Class II patients (2 points score) had an intermediate favorable outcome of 57%, and class III (score 3 points) had the least favorable outcome at 37%. The ROC analysis showed better predictability to prevailing grading systems (AUC = 0.69; P = .04). Kaplan-Meier analysis showed statistically significant difference between the 3 subclasses of the proposed grading system for post-SRS dAVF obliteration (P = .001).

CONCLUSION

The proposed dAVF grading system incorporates angiographic, anatomic, and clinical parameters and improves the prediction of the outcomes following SRS for dAVF as compared to the existing scoring systems.

Arteriovenous fistulas of the Vein of Galen region in adults: Endovascular treatment

PURPOSE

Arteriovenous fistulas of the Vein of Galen region in adults (Ad-VGAVF) are an uncommon entity with specific anatomic features. The aim of this article is to present our experience in the endovascular treatment of this pathology and to propose a therapeutic strategy based precisely on the angioarchitecture of these lesions.

MATERIALS AND METHODS

During a 20-year period, 10 patients underwent endovascular treatment of Ad-VGAVF. They were nine men and one woman with a mean age of 50 years (23-66 years) treated with the same embolization strategy. Clinical presentation, angiographic characteristics, therapeutic strategy, and clinical outcomes were recorded.

RESULTS

All patients were treated exclusively by endovascular approach. Transarterial access was performed in eight patients and combined transvenous and transarterial access in two. Complete obliteration of the fistula was obtained in all patients. There were no intraprocedural complications. Post-embolization neurological symptoms occurred in 5 of 10 with complete resolution at six months in all of them.

CONCLUSION

Arteriovenous fistulas of the Vein of Galen region in adults present uniform angioarchitecture despite their low prevalence. Based on this constant angioarchitecture and especially on the features of its venous drainage, judicious embolization strategy is feasible and effective. Ten cases treated entirely by endovascular approach with excellent clinical and angiographic outcomes show this treatment like a curative alternative for this entity of deep topography and severe prognosis.

Hemorrhage risk of cerebral dural arteriovenous fistulas following Gamma Knife radiosurgery in a multicenter international consortium

OBJECTIVE

The authors performed a study to evaluate the hemorrhagic rates of cerebral dural arteriovenous fistulas (dAVFs) and the risk factors of hemorrhage following Gamma Knife radiosurgery (GKRS).

METHODS

Data from a cohort of patients undergoing GKRS for cerebral dAVFs were compiled from the International Radiosurgery Research Foundation. The annual posttreatment hemorrhage rate was calculated as the number of hemorrhages divided by the patient-years at risk. Risk factors for dAVF hemorrhage prior to GKRS and during the latency period after radiosurgery were evaluated in a multivariate analysis.

RESULTS

A total of 147 patients with dAVFs were treated with GKRS. Thirty-six patients (24.5%) presented with hemorrhage. dAVFs that had any cortical venous drainage (CVD) (OR = 3.8, p = 0.003) or convexity or torcula location (OR = 3.3, p = 0.017) were more likely to present with hemorrhage in multivariate analysis. Half of the patients had prior treatment (49.7%). Post-GRKS hemorrhage occurred in 4 patients, with an overall annual risk of 0.84% during the latency period. The annual risks of post-GKRS hemorrhage for Borden type 2-3 dAVFs and Borden type 2-3 hemorrhagic dAVFs were 1.45% and 0.93%, respectively. No hemorrhage occurred after radiological confirmation of obliteration. Independent predictors of hemorrhage following GKRS included nonhemorrhagic neural deficit presentation (HR = 21.6, p = 0.027) and increasing number of past endovascular treatments (HR = 1.81, p = 0.036).

CONCLUSIONS

Patients have similar rates of hemorrhage before and after radiosurgery until obliteration is achieved. dAVFs that have any CVD or are located in the convexity or torcula were more likely to present with hemorrhage. Patients presenting with nonhemorrhagic neural deficits and a history of endovascular treatments had higher risks of post-GKRS hemorrhage.

Brain arteriovenous malformation with transdural blood supply: Current status

Arterial blood supply to a brain arteriovenous malformation (BAVM) is mainly derived from the internal carotid artery (ICA) and vertebral basilar artery (VBA) system. However, in certain cases, arteries supplying the meninges may also contribute to the blood supply of the BAVM, resulting in the formation of a BAVM with transdural blood supply (TBS). To review the current status of BAVM with TBS, a literature search was performed in the PubMed database. Articles were screened for relevance and suitability of data. According to recent studies, the mechanisms by which TBS to a BAVM forms are mainly classified into the congenital and acquired type. BAVM with TBS is common in elderly patients and is characterized by intracranial hemorrhage, epilepsy, chronic headache and increased intracranial pressure. Digital subtraction angiography is the gold standard for diagnosing BAVM with TBS. Superselective angiography is also important. Treatments for BAVM with TBS include surgical resection, endovascular treatment (EVT), stereotactic radiosurgery and combined treatment. Surgical resection is difficult to perform. EVT has become the major therapy for treating BAVM with TBS due to its low procedural invasiveness. Combination of surgical resection and EVT may be a good option. In addition, stereotactic radiosurgery is frequently used as a complementary treatment to surgical and endovascular interventions. The prognosis of BAVM with TBS is not favorable, as the defect involves a complex arterial supply system.

Obstructive hydrocephalus associated with spontaneous dural arteriovenous fistula: A case report

RATIONALE

Dural arteriovenous fistulae (DAVF) are vascular disorders depicted with direct interconnection between dural arteries and cerebral venous sinuses and/or cortical veins. Only a hand full of cases have been reported in literature. DAVF obstructing the 3rd ventricle and quadrigeminal cistern resulting in hydrocephalus is very rare.

PATIENT CONCERNS

We present a 55-year-old female with 2 years history of headaches and blurring of vision. Cranial nerves examinations were unremarkable.

DIAGNOSES

Magnetic Resonance Imaging (MRI) and digital subtraction angiography showed multiple tortuous vascular malformation in the 3rd ventricle and quadrigeminal cistern resulting in obstructive hydrocephalus (OHC).

INTERVENTIONS

We utilized endovascular embolization treatment option to obliterate the lesion. We used Onyx embolization agent (ev3 Neurovascular, Irvine, CA) to embolize the lesion via the transarterial route.

OUTCOMES

The OHC resolved spontaneously after the endovascular embolization of the DAVF. The patient recovered with no further neurologic complication. Two years follow-up reveal no recurrence of the DAVF as well as hydrocephalus.

LESSONS

Adequate knowledge on the vascular anatomy is very crucial in managing DAVF.

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.

Successful treatment of a case of tentorial dural arteriovenous fistula causing subarachnoid hemorrhage with invagination of the brainstem by huge and multiple venous pouches

Background:

We present a case of tentorial dural arteriovenous fistula (TDAVF) causing subarachnoid hemorrhage with mass effect of large venous pouches, which was struggling to diagnosis and management due to complex vasculature and severe general condition.

Case Description:

A 43-year-old man was transferred to our hospital due to sudden consciousness disturbance. A neurological examination revealed tetraparesis and pupil dilatation with no light reflex. Imaging findings showed a large lesion in the brainstem with subarachnoid and intraventricular hemorrhage. Since there were multiple feeding arteries and large and multiple venous pouches on vascular imaging, we diagnosed the patient with TDAVF. Because of a high-flow arteriovenous shunt and the presence of large venous pouches, it appeared to be very difficult to approach the shunting point by direct surgery. Therefore, we first performed transarterial endovascular treatment with 25% n-butyl-2-cyanoacrylate to shrink the venous pouches and to reduce the pressure of the posterior fossa, followed by direct radical interruption of the shunting point using the craniotomy maneuver. Postoperative vascular imaging revealed disappearance of abnormal feeding arteries, draining veins, and venous pouches. The patient was discharged and transferred to a rehabilitation hospital with a modified Rankin Scale Score of 3. Accurate interpretation of the detailed vasculature preoperatively and an appropriate treatment strategy using endovascular and direct surgical technique are required to achieve a satisfactory outcome for difficult-to-treat dural arteriovenous fistulas.

Conclusions:

This combined maneuver with endovascular embolism as complementary pretreatment for radical surgery is useful for a case with high-flow shunting and large venous pouches.

A Propensity Score-Matched Cohort Analysis of Outcomes After Stereotactic Radiosurgery in Older versus Younger Patients with Dural Arteriovenous Fistula: An International Multicenter Study

OBJECTIVE

This study aims to evaluate the outcomes of Gamma Knife stereotactic radiosurgery (SRS) for dural arteriovenous fistulas (dAVFs) in older patients (≥65 years) compared with younger patients (age <65 years).

METHODS

Two groups with a total of 96 patients were selected from a database of 133 patients with dAVF from 9 international medical centers with a minimum 6 months follow-up. A 1:2 propensity matching was performed by nearest-neighbor matching criteria based on sex, Borden grade, maximum radiation dose given, and location. The older cohort consisted of 32 patients and the younger cohort consisted of 64 patients. The mean overall follow-up in the combined cohort was 42.4 months (range, 6-210 months).

RESULTS

In the older cohort, a transverse sinus location was found to significantly predict dAVF obliteration (P = 0.01). The post-SRS actuarial 3-year and 5-year obliteration rates were 47.7% and 78%, respectively. There were no cases of post-SRS hemorrhage. In the younger cohort, the cavernous sinus location was found to significantly predict obliteration (P = 0.005). The 3-year and 5-year actuarial obliteration rates were 56% and 70%, respectively. Five patients (7.8%) hemorrhaged after SRS. Margin dose ≥25 Gy was predictive of unfavorable outcome. The obliteration rate (P = 0.3), post-SRS hemorrhage rate (P = 0.16), and persistent symptoms after SRS (P = 0.83) were not statistically different between the 2 groups.

CONCLUSIONS

SRS achieves obliteration in most older patients with dAVF, with an acceptable rate of complication. There was no increased risk of postradiosurgery complications in the older cohort compared with the younger patients.

Tentorial Dural Arteriovenous Fistula Treated Using Transarterial Onyx Embolization

Tentorial dural arteriovenous fistula (DAVF) is a rare vascular disease, which has high risk of intracranial hemorrhage. We present two cases of tentorial DAVF which were successfully treated with single trial of transarterial embolization using Onyx. We briefly reviewed the types of the tentorial DAVF and strategies of treatment.

Changing Clinical and Therapeutic Trends in Tentorial Dural Arteriovenous Fistulas: A Systematic Review

BACKGROUND AND PURPOSE

Tentorial dural arteriovenous fistulas are characterized by a high hemorrhagic risk. We evaluated trends in outcomes and management of tentorial dural arteriovenous fistulas and performed a meta-analysis evaluating clinical and angiographic outcomes by treatment technique.

MATERIALS AND METHODS

We performed a comprehensive literature search for studies on surgical and endovascular treatment of tentorial dural arteriovenous fistulas. We compared the proportion of patients undergoing endovascular, surgical, and combined endovascular/surgical management; the proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas; and proportion of patients with good neurologic outcome across 3 time periods: 1980-1995, 1996-2005, and 2006-2014. We performed a random-effects meta-analysis, evaluating the rates of occlusion, long-term good neurologic outcome, perioperative morbidity, and resolution of symptoms for the 3 treatment modalities.

RESULTS

Twenty-nine studies with 274 patients were included. The proportion of patients treated with surgical treatment alone decreased from 38.7% to 20.4% between 1980-1995 and 2006-2014. The proportion of patients treated with endovascular therapy alone increased from 16.1% to 48.0%. The proportion of patients presenting with ruptured tentorial dural arteriovenous fistulas decreased from 64.4% to 43.6%. The rate of good neurologic outcome increased from 80.7% to 92.9%. Complete occlusion rates were highest for patients receiving multimodality treatment (84.0%; 95% CI, 72.0%-91.0%) and lowest for endovascular treatment (71.0%; 95% CI, 56.0%-83.0%; P < .01). Long-term good neurologic outcome was highest in the endovascular group (89.0%; 95% CI, 80.0%-95.0%) and lowest for the surgical group (73.0%; 95% CI, 51.0%-87.0%; P = .03).

CONCLUSIONS

Patients with tentorial dural arteriovenous fistulas are increasingly presenting with unruptured lesions, being treated endovascularly, and experiencing higher rates of good neurologic outcomes. Endovascular treatment was associated with superior neurologic outcomes but lower occlusion rates.

Stereotactic radiosurgery for intracranial dural arteriovenous fistulas: a systematic review

OBJECT

The goal of this study was to evaluate the obliteration rate of intracranial dural arteriovenous fistulas (DAVFs) in patients treated with stereotactic radiosurgery (SRS), and to compare obliteration rates between cavernous sinus (CS) and noncavernous sinus (NCS) DAVFs, and between DAVFs with and without cortical venous drainage (CVD).

METHODS

A systematic literature review was performed using PubMed. The CS DAVFs and the NCS DAVFs were categorized using the Barrow and Borden classification systems, respectively. The DAVFs were also categorized by location and by the presence of CVD. Statistical analyses of pooled data were conducted to assess complete obliteration rates in CS and NCS DAVFs, and in DAVFs with and without CVD.

RESULTS

Nineteen studies were included, comprising 729 patients harboring 743 DAVFs treated with SRS. The mean obliteration rate was 63% (95% CI 52.4%–73.6%). Complete obliteration for CS and NCS DAVFs was achieved in 73% and 58% of patients, respectively. No significant difference in obliteration rates between CS and NCS DAVFs was found (OR 1.72, 95% CI 0.66–4.46; p = 0.27). Complete obliteration in DAVFs with and without CVD was observed in 56% and 75% of patients, respectively. A significantly higher obliteration rate was observed in DAVFs without CVD compared with DAVFs with CVD (OR 2.37, 95% CI 1.07–5.28; p = 0.03).

CONCLUSIONS

Treatment with SRS offers favorable rates of DAVF obliteration with low complication rates. Patients harboring DAVFs that are refractory or not amenable to endovascular or surgical therapy may be safely and effectively treated using SRS.

Tentorial dural arteriovenous fistula presenting as myelopathy: Case series and review of literature

Dural arteriovenous fistula (DAVF) is a rare type of cerebral arteriovenous malformation. Common presenting symptoms are related to hemorrhage. However, rarely these patients may present with myelopathy. We present two cases of DAVF presenting as rapidly progressive myelopathy. Two treatment options are available: microsurgical interruption of the fistula and endovascular embolization. These treatment options of DAVFs have improved significantly in the last decade. The optimal treatment of DAVFs remains controversial, and there is an ongoing debate as to whether primary endovascular or primary microsurgical treatment is the optimal management for these lesions. However, despite treatment a high percentage of patients are still left with severe disability. The potential for functional ambulation in patients with DAVF is related to the time of intervention. This emphasizes the important of early diagnosis and early intervention in DAVF. The eventual outcome may depend on several factors, such as the duration of symptoms, the degree of disability before treatment, and the success of the initial procedure to close the fistula. The usage of magnetic resonance imaging and selective angiography has significantly improved the ability to characterize DAVFs, however, these lesions remain inefficiently diagnosed. If intervention is delayed even prolonged time in rehabilitation does not change the grave prognosis. This review outlines the presentation, classication and management of DAVF as well as discussing patient outcomes.

Arterial Onyx Embolisation of Intracranial DAVFs with Cortical Venous Drainage

Purpose:

To present our experience with the endovascular management of intracranial dural arteriovenous fistulas with direct cortical venous drainage by trans-arterial embolisation using Onyx.

Materials & Methods:

Between January 2004 and April 2008, 12 consecutive high grade intracranial dural arteriovenous fistulas (Cognard type III (eight patients) or IV (three patients)) were treated by trans-arterial embolisation with Onyx. The majority of cases were treated by Onyx embolisation alone. One case had additional embolisation with n-butyl-2-cyanoacrylate at the same session. Imaging follow-up was obtained in all but one patient (mean 3.6 months).

Results:

Nine patients had a technical success at the end of the embolisation procedure with complete angiographic exclusion of the fistula. Two patients had a small residual fistula at the end of embolisation, one of which had residual mild cortical venous drainage. Both were stable at follow-up angiography. One patient had a residual fistula supplied by the ophthalmic artery, which was thought to be unsafe to embolise and was sent for surgery, which was curative. In one patient the microcatheter ruptured, with a fragment of the distal microcatheter left in the occipital artery. No clinical complications were observed in this series at clinical follow-up (mean 3.3 months). Two patients were noted to have significant radiation dose.

Conclusion:

Endovascular management of intracranial dural arteriovenous fistulas with direct venous cortical drainage by trans-arterial Onyx embolisation is a safe and effective treatment according to our experience. Fluoroscopy times and radiation dose may be a concern.

Co-occurrence of a cerebral cavernous malformation and an orbital cavernous hemangioma in a patient with seizures and visual symptoms: Rare crossroads for vascular malformations

Background:

Cerebral cavernous malformations (CCMs) are angiographically occult vascular malformations of the central nervous system. As a result of hemorrhage and mass effect, patients may present with focal neurologic deficits, seizures, and other symptoms necessitating treatment. Once symptomatic, most often from hemorrhage, CCMs are treated with microsurgical resection. Orbital cavernous hemangiomas (OCHs) are similar but distinct vascular malformations that present within the orbital cavity. Even though CCMs and OCHs are both marked by dilated endothelial-lined vascular channels, they are infrequently seen in the same patient.

Case Description:

We provide a brief overview of the two related pathologies in the context of a patient presenting to our care with concomitant lesions, which were both resected in full without complication.

Conclusion:

This is the first known report that describes a case of concomitant CCM and OCH and explores the origins of two pathologies that are rarely encountered together in neurosurgical practice. Recognition of disparate symptomatologies is important for properly managing these patients.

Clinical approach of using Onyx via transarterial access in treating tentorial dural arteriovenous fistula

OBJECTIVE

In this study, based on clinical presentation and angiographic findings, we try to investigate the possibility to do transarterial embolization using Onyx to treat tentorial dural arteriovenous fistula (TDAVF). Particular attention will be given to the relationship between vascular anatomic characteristics and clinical management.

METHODS

We retrospectively reviewed the clinical and radiologic data of 26 patients with TDAVFs, who were treated via transarterial approach using Onyx (including three cases treating with balloon assisting) at our department from January 2005 to April 2010.

RESULTS

The total obliterated rate was 85.7, 53.8, and 66.7% in the tentorial marginal, lateral, and medial subtype, respectively. Symptoms were improved significantly in the patients whose fistulas were totally and sub-totally obliterated. The mean follow-up duration was 2.9 years. After operation, patients' symptom was dramatically improved indicated by the decrease of individual modified Rankin scale (MRS). Only one patient suffered from temporary paralysis of cranial nerve (CN) III. All 26 patients were clinically stable and without any relapsed, increased, or new symptoms. All patients had resumed their normal activities until the latest follow-up.

CONCLUSION

Treating the TDAVF via transarterial approach using Onyx maybe a feasible clinical practice. The fistula obliterated rate is highly related to the anatomic characteristic, and high complete obliterated rate can be achieved. Our preliminary results showed that Onyx injection with 'balloon assisting' technique can be helpful in some of the cases.

Tentorial dural fistulas: endovascular management and description of the medial dural-tentorial branch of the superior cerebellar artery

BACKGROUND AND PURPOSE

TDAVFs are uncommon causes of spontaneous intracranial hemorrhage. A retrospective review of their management was performed after repeatedly observing a previously under-recognized medial dural-tentorial branch of the SCA.

MATERIALS AND METHODS

Thirteen patients were diagnosed with TDAVFs by CT/MR imaging and DSA during a 5.8-year period. Seven patients presented after intracranial hemorrhage. Twelve patients were treated endovascularly, and one, surgically.

RESULTS

Eleven TDAVFs were located in the midline (7 at the falx cerebelli and 4 at the torcular), and 2 were petrotentorial. All torcular TDAVFs were associated with sinus thrombosis and showed bidirectional drainage relative to the tentorium. No sinus thrombosis was seen in the falx cerebelli subtype, which drained infratentorially only, except in 1 patient who had had unrelated surgery previously. Venous drainage was directly to cortical veins except for 1 petrotentorial and 2 torcular TDAVFs. A branch of the SCA, the medial dural-tentorial artery, was observed in 5 midline TDAVFs. Its anatomy was defined with selective angiography. Endovascular therapy resulted in a cure in 5 and subtotal occlusion in 6, and staged treatment is ongoing in 1 patient. One patient was cured after surgery.

CONCLUSIONS

TDAVFs frequently cause intracranial hemorrhage and therefore warrant treatment. Endovascular therapy proved effective in this series, and arteriography was essential for understanding the various fistula subtypes and for treatment planning. We emphasize the importance of recognizing the medial dural-tentorial artery of the SCA with its characteristic course along the tentorium on angiography. This artery should be included in future anatomic descriptions of the cranial blood supply.

[Intracranial dural arteriovenous fistulae. Experience after 81 cases and literature review]

OBJECTIVES

To analyse the clinical, radiological and therapeutic variables of intracranial dural arteriovenous fistulae (DAVF) treated at our institution, and to assess the validity of the Borden and Cognard classifications and their correlation with the presenting symptoms.

MATERIAL AND METHODS

The DAVF identified were retrospectively analysed. They were classified according to their location, drainage pattern and the Borden and Cognard classifications. We recorded the different treatments, their complications and efficacy.

RESULTS

There were 81DAVF identified between 1975 and 2012. The cavernous sinus (CS) location was the most frequent one. The Borden and Cognard classifications showed an interobserver Kappa index of 0.72 and 0.76 respectively. The odds ratio of aggressive presentation in the presence of cortical venous drainage (CVD) was 19.3 (2.8-132.4). No location, once adjusted by venous drainage pattern, showed significant association with an aggressive presentation. Endovascular transarterial treatment of cavernous sinus DAVF achieved symptomatic improvement of 78%, with a complication rate of 5%. The DAVF of non-CS locations, with CVD, treated surgically were angiographically shown cured in 100% of the cases, with no treatment-related complications.

CONCLUSIONS

The presence of CVD was significantly associated with aggressive presentations. The Borden and Cognard classifications showed little interobserver variability. Endovascular treatment for CS DAVF is safe and relatively effective. Surgical treatment of non-CS DAVF with CVD is safe, effective and the first choice treatment in our environment.

Intracranial dural arteriovenous fistulas: clinical characteristics and management based on location and hemodynamics

Objective

A dural arteriovenous fistula (DAVF) generally refers to a vascular malformation of the wall of a major venous sinus. These lesions have diverse symptoms according to the location and venous drainage, and require multidisciplinary treatment. We report on our experience and analyze the treatment outcome of intracranial DAVFs for a nine-year period.

Methods

Between January 2000 and December 2008, 95 patients with intracranial DAVFs were enrolled in this study. A retrospective review of clinical records and imaging studies of all patients was conducted. Endovascular embolization, surgical interruption, gamma knife stereotactic radiosurgery (GKS), or combinations of these treatments were performed based on clinical symptoms, lesion location, and venous drainage pattern.

Results

Borden type I, II, and III were 34, 48, and 13 patients, respectively. Aggressive presentation was reported in 6% of Borden type I, 31% of Borden type II, and 77% of Borden type III DAVFs, respectively, and DAVFs involving transverse, sigmoid, and superior sagittal sinus. Overall, the rate of complete obliteration was 68%. The complete occlusion rates with a combination treatment of endovascular embolization and surgery, surgery alone, and endovascular embolization were 89%, 86%, and 80%, respectively. When GKS was used with embolization, the obliteration rate was 83%, although it was only 54% in GKS alone. Spontaneous obliteration of the DAVF occurred in three patients. There were a few complications, including hemiparesis (in microsurgery), intracranial hemorrhage (in endovascular embolization), and facial palsy (in GKS).

Conclusion

The hemorrhagic risk of DAVFs is dependent on the location and hemodynamics of the lesions. Strategies for treatment of intracranial DAVFs should be decided according to the characteristic of the DAVFs, based on the location and drainage pattern. GKS can be used as an optional treatment for intracranial DAVFs.

The Natural History of Cerebral Dural Arteriovenous Fistulae

BACKGROUND:

Hemorrhage from cerebral dural arteriovenous fistulae (dAVF) is a considerable source of neurological morbidity and even mortality.

OBJECTIVE:

To evaluate the natural history of cerebral dAVF.

METHODS:

We reviewed our own cohort of 70 dAVF and incorporated results from the literature, synthesizing pooled hemorrhage rates and evaluating risk factors for 395 dAVF in 6 studies.

RESULTS:

No hemorrhages occurred during 409 lesion-years of follow-up of Borden type I dAVF; however, cortical venous drainage developed in 1.4%. Like type I dAVF, type II dAVF demonstrated a female predilection and were most commonly transverse-sigmoid or cavernous. Eighteen percent of type II dAVF presented with hemorrhage (95% confidence interval [CI]: 8%-36%), and the annual hemorrhage rate was 6% (95% CI: 0.1%-19%). Borden type III dAVF demonstrated a male predilection and were most commonly tentorial or petrosal. Thirty-four percent presented with hemorrhage (95% CI: 0.4%-49%), with an annual hemorrhage rate of 10% (95% CI: 4%-20%), increasing to 21% for those with venous ectasia (95% CI: 4%-66%). The hemorrhage rate decreased to 2% for asymptomatic or minimally symptomatic type II or III dAVF (95% CI: 0.2%-8%), and increased to 10% for those presenting with nonhemorrhagic neurological deficits (95% CI: 0.9%-41%) and to 46% for those presenting with hemorrhage (95% CI: 11%-130%).

CONCLUSION:

Venous ectasia is a significant risk factor for hemorrhage among dAVF with cortical venous drainage. In addition, those with hemorrhagic presentation, even compared with nonhemorrhagic neurological deficit presentation, as well as Borden type III dAVF compared with type II dAVF demonstrated a trend toward greater hemorrhage rates.

Stereotactic radiosurgery for cerebral dural arteriovenous fistulas

Object

Given the feasibility of curative surgical and endovascular therapy for cerebral dural arteriovenous fistulas (DAVFs), there is a relative paucity of radiosurgical series for these lesions as compared with their arteriovenous malformation counterparts.

Methods

The authors reviewed records of 56 patients with 70 cerebral DAVFs treated at their institution over the past 6 years. Ten DAVFs (14%) in 9 patients were treated with stereotactic radiosurgery (SRS), with follow-up obtained for 8 patients with 9 DAVFs. They combined their results with those obtained from a comprehensive review of the literature, focusing on obliteration rates, post-SRS hemorrhage rates, and other complications.

Results

In the authors' group of 9 DAVFs, angiographic obliteration was seen in 8 cases (89%), and no post-SRS hemorrhage or complications were observed after a mean follow-up of 2.9 years. Combining the results in these cases with data obtained from their review of the literature, they found 558 DAVFs treated with SRS across 14 series. The overall obliteration rate was 71%; transient worsening occurred in 9.1% of patients, permanent worsening in 2.4% (including 1 death, 0.2% of cases), and post-SRS hemorrhage occurred in 1.6% of cases (4.8% of those with cortical venous drainage [CVD]). The obliteration rate for cavernous DAVFs was 84%, whereas the rates for transversesigmoid and for tentorial DAVFs were 58% and 59%, respectively (adjusted p values, pcav,TS = 1.98 × 10−4, pcav,tent = 0.032). Obliteration rates were greater for DAVFs without CVD (80%, compared with 60% for those with CVD, p = 7.59 × 10−4). Both transient worsening and permanent worsening were less common in patients without CVD than in those with CVD (3.4% vs 7.3% for transient worsening and 0.9% vs 2.4% for permanent worsening).

Conclusions

Stereotactic radiosurgery with or without adjunctive embolization is an effective therapy for DAVFs that are not amenable to surgical or endovascular monotherapy. It is best suited for lesions without CVD and for cavernous DAVFs.

Endovascular treatment of tentorial dural arteriovenous fistulae

Tentorial dural arteriovenous fistula (DAVF) is a rare vascular disease, which accounts for less than 4% of all cases of intracranial DAVF. Because of the high risk of intracranial hemorrhage, patients with tentorial DAVF need aggressive treatment. Management approaches are still controversial, and endovascular treatment has emerged as an effective alternative. In the current work, we describe our experience with the endovascular approach in the treatment of these deep and complex DAVF of the tentorium. Eight patients were treated between January 2006 and July 2009. Six patients (75%) presented with intracranial hemorrhage related to the DAVF rupture. Four patients (50%) had subarachnoid bleeding and two had intraparenchymal hematoma. Endovascular treatment was performed via the transarterial route alone in five cases (62.5%), by the transvenous approach in two cases (25.0%) and in a combined procedure using both arterial and venous routes in one patient (12.5%). Complete obliteration of the fistula was achieved in all cases. The outcome at 15 months was favorable (modified Rankin scale 0-3) in seven (87.5%) patients. Complete cure of the lesion was confirmed in these cases. This paper reports on the effectiveness of endovascular treatment in tentorial DAVF management. The choice of the venous versus the arterial approach is determined by regarding different anatomical dispositions.

Radiosurgery for arteriovenous malformations

Stereotactic radiosurgery is the term coined by Lars Leksell to describe the application of a single, high dose of radiation to a stereotactically defined target volume. In the 1970s, reports began to appear documenting the successful obliteration of arteriovenous malformations (AVMs) with radiosurgery. When an AVM is treated with radiosurgery, a pathologic process appears to be induced that is similar to the response-to-injury model of atherosclerosis. Radiation injury to the vascular endothelium is believed to induce the proliferation of smooth-muscle cells and the elaboration of extracellular collagen, which leads to progressive stenosis and obliteration of the AVM nidus thereby eliminating the risk of hemorrhage. The advantages of radiosurgery - compared to microsurgical and endovascular treatments - are that it is noninvasive, has minimal risk of acute complications, and is performed as an outpatient procedure requiring no recovery time for the patient. The primary disadvantage of radiosurgery is that cure is not immediate. While thrombosis of the lesion is achieved in the majority of cases, it commonly does not occur until two or three years after treatment. During the interval between radiosurgical treatment and AVM thrombosis, the risk of hemorrhage remains. Another potential disadvantage of radiosurgery is possible long term adverse effects of radiation. Finally, radiosurgery has been shown to be less effective for lesions over 10 cc in volume. For these reasons, selection of the optimal treatment for an AVM is a complex decision requiring the input of experts in endovascular, open surgical, and radiosurgical treatment. In the pages below, we will review the world's literature on radiosurgery for AVMs. Topics reviewed will include the following: radiosurgical technique, radiosurgery results (gamma knife radiosurgery, particle beam radiosurgery, linear accelerator radiosurgery), hemorrhage after radiosurgery, radiation induced complications, repeat radiosurgery, and radiosurgery for other types of vascular malformation.

Multidisciplinary treatment of a large cerebral dural arteriovenous fistula using embolization, surgery, and radiosurgery

Dural arteriovenous fistulae are rare lesions composed of abnormal connections between meningeal arteries and the dural sinuses or lepto-meningeal veins. Treatment is challenging because of the small size and wide distribution of the myriad sites of fistulous connection. We present a case of a dural arteriovenous fistula presenting with visual deterioration, pulsatile tinnitus, and intracranial hypertension that was successfully treated with a multidisciplinary approach combining angiographic, surgical, and radiosurgical intervention. This is one of the largest of these formidable lesions treated in this fashion that has been reported.

Selection of treatment modalities or observation of dural arteriovenous fistulas

Cranial dural arteriovenous fistulas (DAVFs) represent an important class of cranial vascular lesions. The clinical significance of these lesions is highly dependent on the pattern of venous drainage, with cortical venous reflux being an important marker of an aggressive, high-risk fistula. For asymptomatic benign fistulas, conservative management, consisting of observation with follow-up, is a reasonable option. For symptomatic benign fistulas or aggressive fistulas, treatment is recommended. A variety of treatment modalities are available for DAVF management, including endovascular techniques, open surgery, and radiosurgery. A multimodality approach is often warranted and can offer improved chances of achieving a cure.

Intracranial dural arteriovenous fistulas: A Review

Dural arteriovenous fistulas are fistulas connecting the branches of dural arteries to dural veins or a venous sinus. Digital subtraction angiography remains the gold standard for diagnosing these fistulas. Endovascular treatment is one of the first line options available for their management. This review article reviews the etiopathogenesis, natural history, common classification systems and various available treatment options.

Stereotactic radiosurgery with or without embolization for intracranial dural arteriovenous fistulas

BACKGROUND

Treatment options for dural arteriovenous fistulas (DAVFs) have expanded with the application of stereotactic radiosurgery (SRS).

OBJECTIVE

To assess the role of SRS with or without embolization, we reviewed our entire DAVF experience.

METHODS

Between 1991 and 2006, 40 patients with 44 DAVFs underwent Gamma knife SRS. Twenty-eight patients had upfront SRS before or after embolization and 12 patients underwent delayed SRS for recurrent or residual DAVFs after initial embolization. The median patient age was 60 years (range, 29-90). DAVFs were diagnosed in 7 patients after they sustained an intracranial hemorrhage. The median SRS target volume was 2.0 mL (range, 0.2-8.2 mL) and the median marginal dose was 21.0 Gy (range, 15-25 Gy).

RESULTS

At a median follow-up of 45 months (range, 23-116 mo), a total of 28 patients (harboring 32 DAVFs) had obliteration confirmed by imaging. We found a 83% obliteration rate in patients who had upfront SRS with embolization and a 67% obliteration rate in patients who only had SRS. One patient died of an intracerebral hemorrhage 2 months after SRS. Cavernous carotid fistulas were associated with higher rates of occlusion (P = .012) and symptom improvement (P = .010) than were transverse-sigmoid sinus-related fistulas.

CONCLUSION

When upfront SRS is possible in conjunction with embolization, successful DAVF obliteration is possible in most patients, especially those with carotid cavernous fistulas. SRS should target the entire fistula regardless of whether it precedes or follows embolization. In selected patients with a small-volume, low-risk DAVF, SRS alone is an effective treatment option in most patients.

Gamma knife radiosurgery for dural arteriovenous fistulas

BACKGROUND

The current management of intracranial dural arteriovenous fistulas (dAVFs) incorporates a multimodal approach involving microneurosurgery, endovascular embolization, and radiosurgery.

OBJECTIVE

To explore the role of Gamma Knife radiosurgery for dAVFs.

METHODS

The series includes patients with dAVFs who had Gamma Knife radiosurgery at the University of Virginia Medical Center between 1989 and 2005 with clinical follow-up through 2008. Medical records were reviewed to obtain clinical history, demographic data, and dosimetry. Radiographic records provided the location and anatomy of the dAVFs. Follow-up angiography was performed 2 to 3 years after treatment, with cure defined as complete obliteration of fistulous flow. Follow-up for clinical symptomology and quality of life was obtained from direct patient and primary physician questionnaires.

RESULTS

Fifty-five patients underwent Gamma Knife radiosurgery for dAVFs during the study period. Twenty patients (36%) presented with intracranial hemorrhage before radiosurgery. Gamma Knife radiosurgery was preceded by craniotomy for microneurosurgical ablation in 11 patients (20%) or endovascular embolization in 36 patients (65%). Follow-up angiography was performed on 46 patients (83%) with documented obliteration in 30 patients (65%). Patients lost to follow-up were classified as treatment failures, adjusting the range of efficacy from 65% to 54%. Three patients (5%) suffered a posttreatment hemorrhage during the follow-up period, but no new permanent neurological deficits resulted from these events.

CONCLUSION

Gamma Knife radiosurgery is an effective adjunct therapy for dAVFs with persistence of flow after open neurosurgical resection or endovascular treatment while still maintaining a role in nonaggressive dAVFs not amenable to either surgery or embolization.

Surgical obliteration in superior petrosal sinus dural arteriovenous fistula

Superior petrosal sinus (SPS) dural arteriovenous fistula (DAVF) is one of tentorial DAVFs with significant morbidity, which usually drains into the petrosal vein and its tributaries. Unless there is a connection with venous sinus, surgical obliteration is required. We present two cases of SPS DAVF which were successfully treated with the presigmoid retrolabyrinthine approach.

Treatment Strategy Based on Multimodal Management Outcome of Cavernous Sinus Dural Arteriovenous Fistula (CSDAVF)

Purpose

Angiographic finding including venous drainage pattern should be correlated to the presenting symptom pattern (SxP) in CSDAVF. We present outcome of CSDAVF management and suggest a strategy according to SxP and type of treatment based on our experience.

Materials and Methods

We evaluated SxP, angiographic type (proliferative, restrictive or late restrictive), mode of treatment (embolization, Gamma Knife Radiation (GKR) or conservative management), mode of embolization (transarterial or transvenous), and final clinical status (cure, improvement, aggravation or no change). Ninety consecutive patients were included from a prospective database. The mean follow-up was 17 months. We compared the outcomes according to SxP, angiographic type, mode of treatment, and embolization using the chi-square or Fisher's exact test.

Results

Ninety patients with 34 proliferative, 40 restrictive, and 16 late restrictive types of CSDAVF were treated by embolization (n = 63), GKR (n = 7), and conservative management (n = 20). Cure or improvement was 91% after embolization, 88% after conservative management, and 72% after GKR. Following embolization, 100% of 24 proliferative types, 87% of 30 restrictive types, and 90% of 10 late restrictive types were cured or improved. Cure or improvement after transvenous embolization was 98% (43/44) compared with 88% (15/17) after transarterial embolization (p = 0.003).

Conclusion

Various factors of SxP, angiographic type, and mode of treatment should be considered in order to obtain a more favorable outcome for patients with CSDAVF. Embolization via venous approach tended to result in a more complete cure than that via arterial approach.

Multimodality treatment of intracranial dural arteriovenous fistulas in the Onyx era: a single center experience

BACKGROUND

The results of treatment of intracranial dural arteriovenous fistulas (DAVFs) since Onyx became available as an embolic agent at our institution is reported. An algorithm is presented for treatment of DAVFs with Onyx, and the role of endovascular transvenous, surgical, and radiosurgical approaches are presented.

METHODS

Thirty-two patients with DAVFs treated between November 2005 and November 2008 by endovascular embolization, surgery, or radiosurgery were identified by a retrospective chart review. Treatment strategies were based on the location or complexity of the fistula and the patient's clinical status. Data collected included DAVF characteristics, obliteration rates, complications, and outcomes. The results were analyzed and correlated with the treatment modality.

RESULTS

Presenting symptoms were as follows: hemorrhage (n = 12 patients), headaches (n = 12), tinnitus (n = 5), orbital symptoms (n = 7), and seizures (n = 1). Thirty patients were treated by endovascular embolization (transarterial only with Onyx-21, transvenous only with platinum coils-6, transarterial [Onyx] and transvenous [coils]-3). Five patients (4 after incomplete/failed embolization) had surgical excision of the fistula. Three patients were treated with Gamma Knife radiosurgery (primary-1, 2 after incomplete/failed embolization). The locations of the fistulas were transverse sigmoid (10 patients), petrotentorial (7 patients), indirect carotid cavernous fistula (7 patients), parasagittal/falcine (3 patients), middle fossa dura (3 patients), torcula (1 patient), and anterior fossa dura (1 patient). The distribution of patients according to Borden classification was I-6, II-13, and III-13. Complete obliteration of the fistula was achieved in 26/32 (81%) patients after multimodal treatment. All surgical cases had complete obliteration. In the high-risk group with cortical venous reflux, 23/26 (89%) patients were cured. Endovascular complications included a stuck microcatheter tip with fracture of the tip in two patients and cranial nerves V and VII palsies in one patient. At last follow-up (range 1-36 months), 24 patients had modified Rankin score of 0-2, 5 patients had modified Rankin score of 3-5, and 3 patients were dead. Two patients died during admission due to the insult of the hemorrhage, and one died after an accidental fall with subsequent traumatic subdural hematoma.

CONCLUSIONS

Multimodality treatment of DAVFs has high success rates for cure at our center. Transarterial embolization with Onyx has become the primary treatment for intracranial DAVFs at our center and is associated with high safety profile and efficacy. Transvenous coil embolization is still preferred in DAVFs with supply from arterial branches supplying cranial nerves, predominant internal carotid artery feeders and potential extracranial-intracranial collateral anastomosis. In our series, patients with incompletely treated DAVFs were treated with surgery and those with partially treated type I fistulas had radiosurgery for palliation.

Tentorial dural fistula with giant venous ampulae treated with embolisation and surgery. A case report

Tentorial dural arteriovenous fistulas are rare and complex lesions in deep locations with unusual vascular anatomy and critical surrounding neuroanatomy. A rare case presenting a complex fistula with a giant venous draining ampulae, causing headaches and visual troubles is presented. We describe the case of a 52-year-old woman admitted in our department for headaches and visual troubles. Magnetic resonance imaging and cerebral angiography showed a tentorial dural arteriovenous fistula draining in a giant tentorial venous ampulae and leptomeningeal veins. The patient was embolised via an arterial route with a good clinical and radiological result. However, 4 days later she presented a sudden change of her clinical status with coma, left hemiparesis and a right midriasis. The cerebral computed tomography scan showed a huge occipital haemorrhagic mass and a severe cerebral oedema. An emergent surgical procedure was decided realising evacuation of the occipital haematoma and a complete resection of the giant venous ampoule. The neck of the ampulae was sutured and clipped at its dural entrance. Postoperatively a new embolisation was realised because of persistent of a small dural fistulae with occipital leptomeningeal drainage. The patient recovered rapidly with only a residual hemianopsy. Treatment of dural AV malformation represent a serious challenge. Our report describes an unusual case of a tentorial dural complex fistula treated by an endovascular procedure with secondary clinical aggravation that needed emergent surgical therapy. Even in a case for good immediate radiological result after endovascular procedure, dural arteriovenous fistulas with giant venous ampulae and important venous engorgement, need closed follow-up, because of the possibility of aggravation secondary to venous thrombosis and haemorrhage. Treatment and patophysiology of the aggravation mechanism are discussed.

Tentorial dural arteriovenous fistula presenting with quadriparesis: case report and review of the literature

Tentorial dural arteriovenous fistulas (TDAVFs) draining into the spinal venous system are rare lesions. The clinical presentation can be devastating and the diagnosis delayed because of the initial nonspecific imaging and laboratory findings. We report a case of a 20-year-old woman with a rapidly progressive myelopathy, who was found to have a left TDAVF, fed by a single arterial feeder with drainage into the perimedullary venous system. The fistula was surgically clipped. The patient showed neurologic improvement at her 3-month follow-up but still had significant weakness of all 4 extremities. Early diagnosis is key as the neurologic symptoms are reversible with appropriate treatment. We review the relevant literature, imaging characteristics, and treatment modalities for TDAVF.

Vein of Galen aneurysms: presentation and endovascular management

BACKGROUND

We present our experience with managing 13 cases of vein of Galen aneurysm with a special focus on endovascular strategies. This clinical review deals with the multivariable clinical presentation of vein of Galen aneurysms and the role of transarterial endovascular treatment.

METHODS

Thirteen patients diagnosed with vein of Galen aneurysms have been reviewed. Clinical presentation, diagnostic modalities and treatment strategies are also documented for each. MRI and three-dimensional CT angiogram (3D CTA) were performed for all patients. Transarterial embolization with Histoacryl was performed in 8 patients proved to have true vein of Galen aneurysmal malformation (VGAM).

RESULTS

Clinical presentation was variable including hydrocephalus, headaches, heart failure, coma, epilepsy, and even left orbital swelling. MRI demonstrated large vein of Galen aneurysms in all the cases. 3D CTA demonstrated true VGAM in 10 patients. Two cases proved to have vein of Galen varices. Endovascular treatment was conducted successfully in 8 patients and resulted in arrest of head growth, resolution of headaches and improvement of cardiac condition.

CONCLUSION

The transarterial approach proved to be a successful way of management of true VGAM that yielded better outcomes.

Dural arteriovenous fistulas draining into the petrosal vein or bridging vein of the medulla: possible homologs of spinal dural arteriovenous fistulas. Clinical article

OBJECT

Dural arteriovenous fistulas (DAVFs) with leptomeningeal venous reflux generally pose a high risk of aggressive manifestations including hemorrhage. Among DAVFs, there is a peculiar type that demonstrates direct drainage into the bridging vein rather than the dural venous sinus. The purpose of this study was to investigate the characteristics of DAVFs that drain directly into the petrosal vein or the bridging vein of the medulla oblongata.

METHODS

Eleven consecutive cases of DAVFs that drained directly into the petrosal vein and 6 that drained directly into the bridging vein of the medulla were retrospectively reviewed. These cases were evaluated and/or treated at Hospital de Bicêtre in Paris, France, over a 27-year period. A review of previously reported cases was also performed.

RESULTS

Both of these "extrasinusal"-type DAVFs demonstrated very similar characteristics. There was a significant male predominance (p < 0.001) for this lesion, and a significantly higher incidence of aggressive neurological manifestations including hemorrhage or venous hypertension than in DAVFs of the transverse-sigmoid or cavernous sinus (p < 0.001). This finding was considered to be attributable to leptomeningeal venous reflux. Regarding treatment, endovascular embolization (either transarterial or transvenous) is frequently difficult, and surgery may be an effective therapeutic choice in many instances.

CONCLUSIONS

Embryologically, both the petrosal vein and the bridging vein of the medulla are cranial homologs of the spinal cord emissary bridging veins that drain the pial venous network. The authors believe that DAVFs in these locations may be included in a single category with spinal DAVFs because of their similar clinical characteristics.

Use of onyx in the management of tentorial dural arteriovenous fistulae

OBJECTIVE

Tentorial dural arteriovenous fistula (DAVF) is an uncommon disease with a poor natural history. Management of tentorial DAVF remains controversial. This study reports the technique and results of transarterial embolization using Onyx (Micro Therapeutics Inc., Irvine, CA) in the treatment of a series of 14 patients with tentorial DAVFs.

METHODS

We retrospectively reviewed the clinical and radiological data of 14 patients with tentorial DAVFs who were treated by transarterial embolization using Onyx at Shanghai Changhai Hospital between 2005 and 2008.

RESULTS

Twelve patients presented with subarachnoid or intraventricular hemorrhage. Complete cure was achieved in 11 patients after 1 procedure and in 1 patient after 2 procedures. Incomplete cure was obtained in the other 2 patients. One patient experienced vessel perforation; another had microcatheter retention. All of the patients recovered well, except 1 patient who died of severe infection caused by ventricular drainage. Clinical follow-up showed no rebleeding or worsening. Follow-up angiography in 8 patients with total occlusion demonstrated no recurrence.

CONCLUSION

These results suggest that transarterial embolization using Onyx is feasible and effective for the management of tentorial DAVFs.

The role of surgery for high-grade intracranial dural arteriovenous fistulas: importance of obliteration of venous outflow

Object

Surgical intervention may be required if endovascular embolization is insufficient to completely obliterate intracranial dural arteriovenous fistulas (DAVFs). The authors report their 14-year experience with 23 patients harboring diverse intracranial DAVFs that required surgical intervention.

Methods

Between 1993 and 2007, 23 patients underwent surgery for intracranial DAVFs. The following types of DAVFs were treated: superior petrosal sinus (in 10 patients); parietooccipital (in 3); confluence of sinuses and ethmoidal (in 2 each); and tentorial, falcine, occipital, transverse-sigmoid, superior sagittal, and cavernous sinuses (in 1 patient each). In all cases, the authors' goal was to obliterate the DAVF venous outflow by direct surgical interruption of the leptomeningeal venous drainage. Transarterial embolization was used primarily as an adjunct to decrease flow to the DAVF prior to definitive treatment.

Results

Complete angiographic obliteration of the DAVF was achieved in all cases. There were no complications of venous hypertension, venous infarction, or perioperative death. There were no recurrences and no further clinical events (new hemorrhages or focal neurological deficits) after a mean follow-up of 45 months.

Conclusions

The authors' experience emphasizes the importance of occluding venous outflow to obliterate intracranial DAVFs. Those that drain purely through leptomeningeal veins can be safely obliterated by surgically clipping the arterialized draining vein as it exits the dura. Radical excision of the fistula is not necessary.

Endovascular treatment resolves non-hemorrhagic brainstem dysfunction due to tentorial dural AV fistula

Tentorial dural arteriovenous fistulas (tDAVF) clinically present usually with subarachnoid and/or intraparenchymal hemorrhage. Reported rates range from 58% to 92% and neurological deficits occur in 79% to 92% of patients. This is due to venous congestion resulting from retrograde leptomeningeal venous drainage, which rarely, can be clinically silent. A 69-year-old woman presented with vertigo, double vision and gait instability. Cerebral digital subtraction angiography revealed a tDAVF with retrograde cerebellar venous drainage directed through the vein of Galen into the straight sinus. MRI showed extensive cerebellar edema due to venous congestion. Clinical manifestations of cerebellar and brainstem dysfunction resolved completely after transarterial embolization with N-butylcyanoacrylate.