Surgical treatment of anterior cranial fossa dural arterio-venous fistulas (DAVFs): a two-centre experience

Transarterial embolization for anterior cranial fossa dural arteriovenous fistulas: a retrospective single-center study

BACKGROUND

Clip ligation of anterior cranial fossa (ACF) dural arteriovenous fistulas (DAVFs) is the traditionally accepted first-line treatment. Endovascular treatment for ACF DAVFs may achieve good outcomes as endovascular techniques advance. Here we report the clinical and angiographic outcomes in patients with ACF DAVFs who underwent transarterial embolization (TAE) as first-line treatment.

METHODS

Over a 20-year period, 87.0% (40/46) of patients received TAE as first-line treatment. The clinical presentation, angiographic features, treatment strategy, and clinical and angiographic outcomes are described in this article.

RESULTS

Forty patients underwent TAE as first-line treatment. There were 36 men and 4 women, with a mean age of 55.6 (55.6±7.4) years. A total of 64 embolization attempts were performed. The middle meningeal artery (66.7%, 12/18) and the ophthalmic artery (54.2%, 13/24) were the most frequently used arterial access routes for complete embolization. The second option was the sphenopalatine artery (46.7%, 7/15). Complications, that is, retinal ischemia, occurred in one patient (2.5%). The total immediate complete occlusion rate for TAE was 82.5% (33/40). Two patients needed surgery for incomplete embolization. When followed up (90%, 36/40), one patient (2.8%, 1/36) reported worsening symptoms due to retinal ischemia following TAE. Although fewer than 50% of the patients received digital subtraction angiography follow-up, there were no recurrences.

CONCLUSIONS

We show that TAE is safe and effective in the treatment of ACF DAVFs in this study of 40 patients, making it a viable alternative to surgical ligation and transvenous embolization. More research is needed to compare these various treatment modalities.

Natural history, angiographic presentation and outcomes of anterior cranial fossa dural arteriovenous fistulas

BACKGROUND

Anterior cranial fossa dural arteriovenous fistulas (ACF-dAVFs) are aggressive vascular lesions. The pattern of venous drainage is the most important determinant of symptoms. Due to the absence of a venous sinus in the anterior cranial fossa, most ACF-dAVFs have some degree of drainage through small cortical veins. We describe the natural history, angiographic presentation and outcomes of the largest cohort of ACF-dAVFs.

METHODS

The CONDOR consortium includes data from 12 international centers. Patients included in the study were diagnosed with an arteriovenous fistula between 1990-2017. ACF-dAVFs were selected from a cohort of 1077 arteriovenous fistulas. The presentation, angioarchitecture and treatment outcomes of ACF-dAVF were extracted and analyzed.

RESULTS

60 ACF-dAVFs were included in the analysis. Most ACF-dAVFs were symptomatic (38/60, 63%). The most common symptomatic presentation was intracranial hemorrhage (22/38, 57%). Most ACF-dAVFs drained through cortical veins (85%, 51/60), which in most instances drained into the superior sagittal sinus (63%, 32/51). The presence of cortical venous drainage predicted symptomatic presentation (OR 9.4, CI 1.98 to 69.1, p=0.01). Microsurgery was the most effective modality of treatment. 56% (19/34) of symptomatic patients who were treated had complete resolution of symptoms. Improvement of symptoms was not observed in untreated symptomatic ACF-dAVFs.

CONCLUSION

Most ACF-dAVFs have a symptomatic presentation. Drainage through cortical veins is a key angiographic feature of ACF-dAVFs that accounts for their malignant course. Microsurgery is the most effective treatment. Due to the high risk of bleeding, closure of ACF-dAVFs is indicated regardless of presentation.

Endoscope-Controlled High Frontal Approach for Dural Arteriovenous Fistula in Anterior Cranial Fossa

BACKGROUND

Currently, surgical obliterations are a mainstay for treating dural arteriovenous fistula (DAVF) in the anterior cranial fossa (ACF), which has high risks of hemorrhage and functional disorder. By introducing an endoscope into a high frontal approach and utilizing its advantages, we attempted to establish it as a new surgical procedure that eliminates the drawbacks of various approaches that have been used to date.

METHODS

By using 30 clinical datasets of venous-phase head computed tomography angiogram, measurements and comparisons on a 3-dimensional workstation were performed to identify the appropriate positioning of keyhole craniotomy for endoscope-controlled high frontal approach (EHFA). Based on these data, a cadaver-based surgery was simulated to verify the feasibility of EHFA and develop an efficient procedure.

RESULTS

In EHFA, though raising the position of the keyhole craniotomy made the operative field deeper, significant advantages were obtained in the angle between the operative axis and the medial-anterior cranial base and the amount of bone removal required at the anterior edge of craniotomy. Minimally invasive EHFA, performed through a keyhole craniotomy without opening the frontal sinus, proved to be feasible on 10 sides of 5 cadaver heads. Moreover, 3 patients with DAVF in ACF were successfully treated by clipping the fistula via EHFA.

CONCLUSIONS

EHFA, which provided a direct corridor to the medial ACF at the level of the foramen cecum and crista galli and the minimum necessary operative field, was found to be a suitable procedure for clipping the fistula of DAVF in ACF.

Development of Anterior Cranial Fossa Dural Arteriovenous Fistula and Supraclinoid Internal Carotid Artery Pseudoaneurysm Following Frontobasal Trauma: A Case Report and Literature Review

Cerebrovascular injuries resulting from frontobasal head trauma represent a range of imaging and clinical presentations. Severe cerebrovascular injuries such as vessel transection commonly present with profound neurological deficits and are often easily identified with routine imaging. However, small intimal injuries and dissections may be challenging to detect and may be clinically silent or masked by additional injuries in the setting of polytrauma. The onset of symptoms and complications from cerebrovascular injuries may be delayed from the time of initial presentation, and failure to recognize and diagnose these injuries may result in devastating outcomes if management is delayed. In this case report, we present a case of frontobasal craniofacial trauma that resulted in an anterior cranial fossa dural arteriovenous fistula (ACF-dAVF) and supraclinioid segment internal carotid artery (ICA) pseudoaneurysm.

Analysis of Etiology, Diagnosis, and Treatment Strategy and Efficacy of Pulsatile Tinnitus Caused by Abnormal Vascular Anatomy

OBJECTIVE

To investigate the etiology, clinical characteristics, diagnosis, and treatment strategies and efficacy of pulsatile tinnitus (PT) caused by vascular anatomy abnormality.

METHODS

The clinical data of 45 patients with PT in our hospital from 2012 to 2019 were collected and retrospectively analyzed.

RESULTS

All 45 patients had vascular anatomical abnormalities. The patients were divided into 10 categories according to the different locations of vascular abnormalities: sigmoid sinus diverticulum (SSD), sigmoid sinus wall dehiscence (SSWD), SSWD with high jugular bulb, pure dilated mastoid emissary vein, aberrant internal carotid artery (ICA) in the middle ear, transverse-sigmoid sinus (TSS) transition stenosis, TSS transition stenosis with SSD, persistent occipital sinus stenosis, petrous segment stenosis of ICA, and dural arteriovenous fistula. All patients complained of PT synchronous with heartbeat rhythm. Endovascular interventional therapy and extravascular open surgery were used according to the location of the vascular lesions. Tinnitus disappeared in 41 patients, was significantly relieved in 3 patients, and was unchanged in 1 patient postoperatively. Except for one patient with transient headache postoperatively, no obvious complications occurred.

CONCLUSION

PT caused by vascular anatomy abnormalities can be identified by detailed medical history and physical and imaging examination. PT can be relieved or even completely alleviated after appropriate surgical treatments.

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.

Anterior interhemispheric approach for anterior fossa dural arteriovenous fistulas

Anterior fossa dural arteriovenous fistulas (AF-DAVF) usually display a cortical venous drainage and are therefore at risk for rupture. Microsurgery is traditionally considered in many centers as the first-line treatment since endovascular treatment (EVT) entails a lower cure rate and significant ophthalmic risks. The anterior interhemispheric approach (AIA), originally described by Mayfrank in 1996, seems to offer the effectiveness of microsurgery while limiting the risks related to subfrontal craniotomy. The objective of this study was to analyze the surgical outcomes of patients who underwent this surgical approach for the treatment of AF-DAVF. We hereby describe our 10 years' experience of patients treated for an AF-DAVF with this technique in our institution and retrospectively analyzed our results. In addition, we describe our operative technique and its specificities. Eleven patients with AF-DAVF were included in our study. The definitive cure of the fistula was confirmed in all cases with postoperative cerebral angiography. All patients had a good neurological outcome and no major complication occurred. Brain retractors were never used during surgery, the frontal sinus was never opened neither, and anosmia was never observed after surgery. Anterior interhemispheric approach seems to be safe and effective to treat AF-DAVF with lower risks than other surgical approaches. This technique could be more widely considered when facing such midline vascular lesion.

Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR): rationale, design, and initial characterization of patient cohort

OBJECTIVE

Cranial dural arteriovenous fistulas (dAVFs) are rare lesions, hampering efforts to understand them and improve their care. To address this challenge, investigators with an established record of dAVF investigation formed an international, multicenter consortium aimed at better elucidating dAVF pathophysiology, imaging characteristics, natural history, and patient outcomes. This report describes the design of the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) and includes characterization of the 1077-patient cohort.

METHODS

Potential collaborators with established interest in the field were identified via systematic review of the literature. To ensure uniformity of data collection, a quality control process was instituted. Data were retrospectively obtained.

RESULTS

CONDOR comprises 14 centers in the United States, the United Kingdom, the Netherlands, and Japan that have pooled their data from 1077 dAVF patients seen between 1990 and 2017. The cohort includes 359 patients (33%) with Borden type I dAVFs, 175 (16%) with Borden type II fistulas, and 529 (49%) with Borden type III fistulas. Overall, 852 patients (79%) presented with fistula-related symptoms: 427 (40%) presented with nonaggressive symptoms such as tinnitus or orbital phenomena, 258 (24%) presented with intracranial hemorrhage, and 167 (16%) presented with nonhemorrhagic neurological deficits. A smaller proportion (224 patients, 21%), whose dAVFs were discovered incidentally, were asymptomatic. Many patients (85%, 911/1077) underwent treatment via endovascular embolization (55%, 587/1077), surgery (10%, 103/1077), radiosurgery (3%, 36/1077), or multimodal therapy (17%, 184/1077). The overall angiographic cure rate was 83% (758/911 treated), and treatment-related permanent neurological morbidity was 2% (27/1467 total procedures). The median time from diagnosis to follow-up was 380 days (IQR 120-1038.5 days).

CONCLUSIONS

With more than 1000 patients, the CONDOR registry represents the largest registry of cranial dAVF patient data in the world. These unique, well-annotated data will enable multiple future analyses to be performed to better understand dAVFs and their management.

Intervention for unruptured high-grade intracranial dural arteriovenous fistulas: a multicenter study

OBJECTIVE

The risk-to-benefit profile of treating an unruptured high-grade dural arteriovenous fistula (dAVF) is not clearly defined. The aim of this multicenter retrospective cohort study was to compare the outcomes of different interventions with observation for unruptured high-grade dAVFs.

METHODS

The authors retrospectively reviewed dAVF patients from 12 institutions participating in the Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR). Patients with unruptured high-grade (Borden type II or III) dAVFs were included and categorized into four groups (observation, embolization, surgery, and stereotactic radiosurgery [SRS]) based on the initial management. The primary outcome was defined as the modified Rankin Scale (mRS) score at final follow-up. Secondary outcomes were good outcome (mRS scores 0-2) at final follow-up, symptomatic improvement, all-cause mortality, and dAVF obliteration. The outcomes of each intervention group were compared against those of the observation group as a reference, with adjustment for differences in baseline characteristics.

RESULTS

The study included 415 dAVF patients, accounting for 29, 324, 43, and 19 in the observation, embolization, surgery, and SRS groups, respectively. The mean radiological and clinical follow-up durations were 21 and 25 months, respectively. Functional outcomes were similar for embolization, surgery, and SRS compared with observation. With observation as a reference, obliteration rates were higher after embolization (adjusted OR [aOR] 7.147, p = 0.010) and surgery (aOR 33.803, p < 0.001) and all-cause mortality was lower after embolization (imputed, aOR 0.171, p = 0.040). Hemorrhage rates per 1000 patient-years were 101 for observation versus 9, 22, and 0 for embolization (p = 0.022), surgery (p = 0.245), and SRS (p = 0.077), respectively. Nonhemorrhagic neurological deficit rates were similar between each intervention group versus observation.

CONCLUSIONS

Embolization and surgery for unruptured high-grade dAVFs afforded a greater likelihood of obliteration than did observation. Embolization also reduced the risk of death and dAVF-associated hemorrhage compared with conservative management over a modest follow-up period. These findings support embolization as the first-line treatment of choice for appropriately selected unruptured Borden type II and III dAVFs.

Assessing the rate, natural history, and treatment trends of intracranial aneurysms in patients with intracranial dural arteriovenous fistulas: a Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) investigation

OBJECTIVE

There is a reported elevated risk of cerebral aneurysms in patients with intracranial dural arteriovenous fistulas (dAVFs). However, the natural history, rate of spontaneous regression, and ideal treatment regimen are not well characterized. In this study, the authors aimed to describe the characteristics of patients with dAVFs and intracranial aneurysms and propose a classification system.

METHODS

The Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database from 12 centers was retrospectively reviewed. Analysis was performed to compare dAVF patients with (dAVF+ cohort) and without (dAVF-only cohort) concomitant aneurysm. Aneurysms were categorized based on location as a dAVF flow-related aneurysm (FRA) or a dAVF non-flow-related aneurysm (NFRA), with further classification as extra- or intradural. Patients with traumatic pseudoaneurysms or aneurysms with associated arteriovenous malformations were excluded from the analysis. Patient demographics, dAVF anatomical information, aneurysm information, and follow-up data were collected.

RESULTS

Of the 1077 patients, 1043 were eligible for inclusion, comprising 978 (93.8%) and 65 (6.2%) in the dAVF-only and dAVF+ cohorts, respectively. There were 96 aneurysms in the dAVF+ cohort; 10 patients (1%) harbored 12 FRAs, and 55 patients (5.3%) harbored 84 NFRAs. Dural AVF+ patients had higher rates of smoking (59.3% vs 35.2%, p < 0.001) and illicit drug use (5.8% vs 1.5%, p = 0.02). Sixteen dAVF+ patients (24.6%) presented with aneurysm rupture, which represented 16.7% of the total aneurysms. One patient (1.5%) had aneurysm rupture during follow-up. Patients with dAVF+ were more likely to have a dAVF located in nonconventional locations, less likely to have arterial supply to the dAVF from external carotid artery branches, and more likely to have supply from pial branches. Rates of cortical venous drainage and Borden type distributions were comparable between cohorts. A minority (12.5%) of aneurysms were FRAs. The majority of the aneurysms underwent treatment via either endovascular (36.5%) or microsurgical (15.6%) technique. A small proportion of aneurysms managed conservatively either with or without dAVF treatment spontaneously regressed (6.2%).

CONCLUSIONS

Patients with dAVF have a similar risk of harboring a concomitant intracranial aneurysm unrelated to the dAVF (5.3%) compared with the general population (approximately 2%-5%) and a rare risk (0.9%) of harboring an FRA. Only 50% of FRAs are intradural. Dural AVF+ patients have differences in dAVF angioarchitecture. A subset of dAVF+ patients harbor FRAs that may regress after dAVF treatment.

Transarterial embolization through the infraorbital artery of the ethmoidal dural arteriovenous fistula causing recurrent epistaxis: illustrative case

BACKGROUND

This report describes an ethmoidal dural arteriovenous fistula (DAVF) presenting with the unusual symptom of recurrent epistaxis and successfully treated with selective transarterial embolization through the infraorbital artery (IOA), which is the first time this route was used to the best of the authors’ knowledge, and reviews the literature focusing on the anatomical consideration of ethmoidal DAVFs causing epistaxis and its treatment approaches.

OBSERVATIONS

A 70-year-old man experienced recurrent intractable epistaxis that bled like a faucet turned on. Cerebral angiography revealed an ethmoidal DAVF supplied by the left anterior ethmoidal artery, both sphenopalatine arteries, both IOAs, and the right angular artery, which drained directly into the frontal cortical veins with a tortuous arterialized ectasia. Microaneurysms around the fistulous location where multiple feeding arteries converge were demonstrated and considered the likely source of the epistaxis. The fistula was completely occluded using transarterial Onyx embolization through the IOA, a branch of the internal maxillary artery. No further epistaxis appeared.

LESSONS

Although extremely rare, ethmoidal DAVFs should be included in the differential diagnosis of recurrent epistaxis. Ethmoidal DAVFs with bleeding sources in the ethmoid sinus and nasal cavity may cause epistaxis. It is important to properly diagnose and treat ethmoidal DAVFs presenting with epistaxis on the basis of a comprehensive anatomical understanding of extensive extracranial-extracranial and extracranial-intracranial anastomoses.

Dural arteriovenous fistula with crista galli erosion in a patient with suspected sinusitis

Dural arteriovenous fistula (dAVF) of the anterior cranial fossa is an aggressive entity with a high risk of intracranial hemorrhage. A 38-year-old woman presented to our institution with nasal obstruction and discharge. Computed tomography (CT) scans performed for suspected sinusitis revealed erosion of the crista galli predominantly on the left side. The frontal and ethmoidal sinuses adjacent to the crista galli were clear and did not communicate with the crista galli. Contrast computed tomography scans revealed ectatic vessels adjacent to the crista galli, coursing on the cortical surface. Cerebral angiography identified an anterior fossa dAVF supplied by the bilateral anterior and posterior ethmoidal arteries and drained by the dilated cortical veins. Based on these findings, we assumed that long-term compression by the pulsatile draining veins caused the erosion. The patient underwent successful microsurgical disconnection procedure of the dAVF with an uneventful postoperative course. We concluded that external erosion of the crista galli could be a sign of aggressive dAVF and requires careful examination.

Efficacy and safety of embolization of dural arteriovenous fistulas via the ophthalmic artery

INTRODUCTION

Dural arteriovenous fistulae (DAVF) are vascular lesions with arteriovenous shunting that may be treated with surgical obliteration or endovascular embolization. Some DAVF, such as anterior cranial fossa DAVF (AC-DAVF) derive their arterial supply from ophthalmic artery branches in nearly all cases, and trans-arterial embolization carries a risk of vision loss. We determined the efficacy and safety of trans-ophthalmic artery embolization of DAVF.

MATERIALS AND METHODS

We performed a retrospective cohort study of all patients with DAVF treated by trans-ophthalmic artery embolization from 2012 to 2020. Primary outcome was angiographic cure of the DAVF. Secondary outcomes included vision loss, visual impairment, orbital cranial nerve injury, stroke, modified Rankin Scale at 90-days, and mortality.

RESULTS

12 patients met inclusion criteria (9 males; 3 females). 10 patients had AC-DAVF. Patient age was 59.7  ±  9.5 (mean ± SD) years. Patients presented with intracranial hemorrhage (4 patients), headache (4 patients), amaurosis fugax (1 patients), or were incidentally discovered (2 patients). DAVF Cognard grades were: II (1 patient), III (6 patients), and IV (5 patients). DAVF were embolized with Onyx (10 patients), nBCA glue (1 patient), and a combination of coils and Onyx (1 patient). DAVF cure was achieved in 11 patients (92%). No patients experienced vision loss, death, or permanent disability. One patient experienced a minor complication of blurry vision attributed to posterior ischemic optic neuropathy. 90-day mRS was 0 (10 patients) and 1 (2 patients).

CONCLUSIONS

Trans-ophthalmic artery embolization is an effective and safe treatment for DAVF.

Anterior Cranial Fossa Dural Arteriovenous Fistulae - Angioarchitecture and Intervention

PURPOSE

Anterior cranial fossa (ACF) dural arteriovenous fistulae (DAVF) are rare, unique, and ominous. While surgical disconnection is considered as the favored management option, endovascular treatment has lately gained importance. We present a single institution experience of seven cases.

METHOD

A retrospective analysis was performed on the institutional patient database. Features analyzed were demographic details, symptoms, angioarchitecture, treatment course, angiographic results, procedural complications, and follow-up.

RESULTS

This study included seven patients. The age at presentation ranged from 5-67 years. Clinical symptomatology was as intracranial hemorrhage in 4 patients and headache, chemosis and seizures in one patient each. The fistulae were paramedian at the ACF base. All DAVFs were Cognard type 4. The arterial feeders were from the anterior ethmoidal branches of the ophthalmic artery in all cases (bilateral in n = 5), frontal branches of the middle meningeal artery (MMA) (n = 6), and multiple ECA branches. The arterial route was the choice for access. Complete fistula obliteration was achieved in all but one patient. A traversed vein underwent rupture in one patient. One patient suffered postsurgical hemorrhage. No clinical or angiographic recurrence was noted.

CONCLUSION

The DAVFs of the ACF are inherently high-grade lesions. Transorbital ECA-ICA branch anastomoses may be recruited as feeders. They may be best managed by multidisciplinary means personalized on an angioarchitectural basis. Endovascular embolization is safe and efficacious when performed through a navigable feeder from the frontal division of the MMA, which according to our interpretation is in anastomosis with the anterior falcine branch of the anterior ethmoidal artery.

Microsurgery "Under the Eaves" Using ORBEYE: A Case of Dural Arteriovenous Fistula of the Anterior Cranial Fossa

BACKGROUND

One of the merits of exoscopes, including ORBEYE, is that they are superior to a microscope in terms of ergonomic features. We report a case of dural arteriovenous fistula (dAVF) that was cured by direct surgery using the ergonomic advantages of ORBEYE.

CASE DESCRIPTION

A 78-year-old man was found to have dAVF of the anterior cranial fossa incidentally. We performed direct surgery via bifrontal craniotomy. Because the frontal sinus was large, we reserved the frontal bone-like eaves in order not to open the frontal sinus. The vertex of his head was sufficiently down to shift the frontal lobe downward with gravity. During surgery, we set the angle of the operative visual axis of ORBEYE approximately horizontal to avoid the reserved frontal bone. We performed a stable operation using ORBEYE in a comfortable posture.

CONCLUSIONS

ORBEYE facilitates ergonomic microsurgery, even under the eaves, with the angle of the operative visual axis approximately horizontal using gravity.

Clinical Characteristics and Microsurgery Treatment of Anterior Cranial Fossa Dural Arteriovenous Fistula

Anterior cranial fossa dural arteriovenous fistulas (DAVFs) represent 6% of all intracranial DAVFs and have a high risk of intracranial hemorrhage. To analyze the clinical characteristics and microsurgery treatment of anterior cranial fossa DAVFs, a retrospective review of 21 patients with anterior cranial fossa DAVFs undergoing microsurgery was performed, including 8 bleeding patients and 13 non-bleeding patients. The Glasgow coma scale (GCS) scores were used to evaluate the conscious states of 8 bleeding patients before and after operation. All patients had no obvious complications and the clinical symptoms were improved after operation. No abnormal fistulas and drainage veins were detected by digital subtraction angiography postoperatively. The GCS scores of 8 bleeding patients showed that the conscious states became better than pre-operation. Of the 21 patients, 9 patients were followed up without recurrence. Taken together, microsurgery is an effective method for the treatment of anterior cranial fossa DAVFs and it is very important for the improvement of bleeding patients' conscious states.

Complication rate, cure rate, and long-term outcomes of microsurgery for intracranial dural arteriovenous fistulae: a multicenter series and systematic review

Although microsurgery is an established treatment modality for intracranial dural arteriovenous fistula (dAVF), data regarding the perioperative complication rate, cure rate, and long-term outcomes remain scarce. The aims of this study were to describe our original experience with microsurgery, including the surgical complications and pitfalls, and conduct a systematic review of the relevant literature. A multicenter cohort of patients with dAVF treated by microsurgery was retrospectively assessed. In addition, the PubMed database was searched for published studies involving microsurgery for dAVF, and the complication rate, cure rate, and long-term outcomes were estimated. The total number of patients in our multicenter series and published articles was 553 (593 surgeries). The overall rates of transient complications, permanent complications, death, and incomplete treatment were 11.4, 4.0, 1.2, and 6.5%, respectively. A favorable outcome was achieved for 90.1% patients, even though almost half of the patients presented with intracranial hemorrhage. Of note, the incidence of recurrence was only one per 8241 patient-months of postoperative follow-up. Surgeries for anterior cranial fossa dAVF were associated with a lower complication rate, whereas those for tentorial dAVF were associated with higher complication and incomplete treatment rates. The complication and incomplete treatment rates were lower with simple disconnection of cortical venous drainage than with radical occlusion/resection of dural shunts. Our findings suggest that the cure rate, complication rates, and outcomes of microsurgery for dAVF are acceptable; thus, it could be a feasible second-line treatment option for dAVF. However, surgeons should be aware of the specific adverse events of microsurgery.

Surgical Obliteration of Anterior Cranial Fossa Dural Arteriovenous Fistulas via Unilateral High Frontal Craniotomy

BACKGROUND

Surgical obliteration is generally recommended for anterior cranial fossa dural arteriovenous fistulas (ACF DAVFs) because of a high risk of bleeding and the difficulty of endovascular approaches. Surgical obliteration is generally performed via a frontobasal craniotomy; however, it is slightly excessive over the target fistula. Here, we present 2 cases of ACF DAVFs treated with small craniotomy without frontal sinus involvement and a review of the related literature.

METHODS

We present 2 cases including a 63-year-old woman who presented with a right-sided ACF DAVF that was fed by both ethmoidal arteries and drained into the right cortical veins (case 1) and a 59-year-old man with right-sided unruptured multiple aneurysms and a left-sided ACF DAVF that was fed by the right ethmoidal artery and drained into the left cortical veins (case 2).

RESULTS

Case 1 underwent surgical obliteration via a right high frontal craniotomy. Case 2 was simultaneously treated with surgical clipping of the multiple aneurysms via a right lateral supraorbital craniotomy and surgical obliteration of the ACF DAVF via a left high frontal craniotomy. These 2 patients had no neurologic deficits, and complete obliteration of all the lesions was confirmed on cerebral angiography.

CONCLUSIONS

Constructing a small corridor and a deep working distance in unilateral small high frontal craniotomy may be a slightly unusual approach; however, it is thought to provide sufficient space and a range of microscopic views that facilitate surgical manipulation without requiring extensive bone work.

Treatment of Ethmoidal Dural Arteriovenous Fistulas: A Meta-analysis Comparing Endovascular versus Surgical Treatment

BACKGROUND

Dural arteriovenous fistulas (DAVFs) in the anterior cranial fossa constitute approximately 1%-1.5% of intracranial vascular malformations. Depending on the drainage patterns, the diagnosis of ethmoidal DAVFs should prompt treatment because of the high risk of bleeding. Available treatments strategies are surgical treatment and the endovascular approach.

OBJECTIVE

To compare the surgical treatment with the endovascular therapy in terms of complete obliteration and perioperative adverse events.

METHODS

This study was performed according to the PRISMA guidelines. Eligible studies were identified through a search of PubMed and Cochrane until February 2019. A random effects model meta-analysis of odds ratios (OR) was conducted and the I-square was used to assess heterogeneity. Good outcome was defined as no neurologic deterioration within 30 days after the procedure.

RESULTS

Five studies comprising 81 patients were included in the meta-analysis. Surgical disconnection was superior to endovascular therapy in terms of postprocedural complete obliteration rate (surgery group, 100% [n = 65/65]; endovascular therapy, 47% [n = 15/32]; OR, 32.19; 95% confidence interval, 5.46-189.72; I² = 9.9%) and 30-day good outcome (surgery group, 98% [n = 63/64]; endovascular therapy, 47% [n = 15/32]; OR, 21.90; 95% confidence interval, 1.94-247.27; I² = 53.6%). No significant differences in terms of 30-day stroke, transient ischemic attack; visual deficit, new-onset seizure, and intracranial hemorrhage were identified.

CONCLUSIONS

Surgical treatment was superior to endovascular therapy in terms of complete obliteration and overall good outcome. Adverse event rates were similar between the 2 groups. Future studies should be conducted to validate our results.

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.

Arterial aneurysms associated with intracranial dural arteriovenous fistulas: epidemiology, natural history, and management. A systematic review

Arterial aneurysms are uncommon among patients with dural arteriovenous fistulae (DAVFs), and there is limited information available to guide treatment decisions in such cases. We performed a systematic review of the literature, including a case of a DAVF associated with a flow-related intraorbital ophthalmic artery (OA) aneurysm that we have recently managed. The purpose of our study was to clarify epidemiology, natural history, and management of these lesions. A total of 43 published cases of DAVF associated aneurysms were found in 26 studies on the topic. Anterior cranial fossa was the most common location (40%), and ethmoidal branches were the most common arterial feeders (55%). In about 63% of cases, the aneurysm was located on artery unrelated to DAVF supply. Approximately 10% of intracranial DAVFs were associated with aneurysms located in the intraorbital OA. Overall, 70% of lesions were Borden type III, and 50% of patients presented with hemorrhage. In approximately 17% of cases, the source of bleeding was a feeding artery aneurysm. All of the reported intraorbital OA aneurysms associated with DAVFs remained stable during follow-up. DAVF associated aneurysms are fairly rare. Anterior cranial fossa location and direct cortical venous drainage are common among these lesions. The aneurysms are less likely to be located on feeding arteries, and hemorrhagic presentation related to flow-related aneurysm rupture is uncommon.