Subarachnoid Hemorrhage of Unknown Cause after Transvenous Embolization of Transverse Sigmoid Sinus Dural Arteriovenous Fistula Followed by Transarterial Embolization: A Case Report.

Objective: Dural arteriovenous fistula (dAVF) is generally treated by endovascular therapy, but transarterial embolization (TAE) carries the risk of potential complications, including distal migration of embolic material, brain infarction, and venous congestion. Intracranial hemorrhage is infrequent but remains a considerable concern. Case Presentation: A man in the seventh decade presented with left hemiparesis. Brain MRI revealed right corona radiata infarction and incidentally identified a left transverse sigmoid sinus dAVF. Under a diagnosis of Borden type III and Cognard type IIb, an endovascular treatment plan was initiated. After an unsuccessful attempt at transvenous embolization, TAE with Onyx (Medtronic, Minneapolis, MN, USA) successfully resolved the dAVF. However, immediate post-treatment CT revealed subarachnoid hemorrhage, leading to decompressive craniotomy. Follow-up DSA showed no residual shunts, and the cause of the bleeding remained unknown. Conclusion: Despite the unknown cause of bleeding, a thorough evaluation of preoperative hemodynamics and diligent postoperative examination is crucial in managing dAVF cases. Further pathological investigations are needed to gain a comprehensive understanding of such occurrences.

Classification, angioarchitecture and treatment outcomes of medullary bridging vein-draining dural arteriovenous fistulas in the foramen magnum region: a multicenter study.

PURPOSE: This study aimed to classify medullary bridging vein-draining dural arteriovenous fistulas (MBV-DAVFs) located around the foramen magnum (FM) according to their location and characterize their angioarchitecture and treatment outcomes. METHODS: Patients with MBV-DAVFs diagnosed between January 2013 and October 2022 were included. MBV-DAVFs were classified into four groups. Jugular vein-bridging vein (JV-BV) DAVF: located in proximity to jugular fossa, Anterior condylar vein (ACV)-BV DAVF: proximity to anterior condylar canal, Marginal sinus (MS)-BV DAVF: lateral surface of FM and Suboccipital cavernous sinus (SCS)-BV DAVF: proximity to dural penetration of vertebral artery. RESULTS: Twenty patients were included, three JV-BV, four ACV-BV, three MS-BV and ten SCS-BV DAVFs, respectively. All groups showed male predominance. There were significant differences in main feeders between JV (jugular branch of ascending pharyngeal artery) and SCS group (C1 dural branch). Pial feeders from anterior spinal artery (ASA) or lateral spinal artery (LSA) were visualized in four SCS and one MS group. Drainage pattern did not differ between groups. Transarterial embolization (TAE) was performed in three, two, one and two cases and complete obliteration was obtained in 100%, 50%, 100% and 0% in JV, ACS, MS and SCS group, respectively. Successful interventions without major complications were finally obtained in 100%, 75%, 100%, and 40% in JV, ACS, MS and SCS group, respectively. CONCLUSION: JV-BV DAVFs were successfully treated using TAE alone. SCS-BV DAVFs were mainly fed by small C1 dural branches of vertebral artery often with pial feeders from ASA or LSA, and difficultly treated by TAE alone.

Bridging the gap between neuroimaging and neurosurgery: a case of epidural arteriovenous fistula with an intradural presentation. Illustrative case.

BACKGROUND: Epidural arteriovenous fistulas (eAVFs) are rare vascular malformations often mistaken for their intradural counterparts due to similar angiographic features. Differentiation between epidural and intradural vascular lesions is crucial as it impacts surgical planning and prognosis. Despite advancements in diagnostic imaging, these entities can be misinterpreted and challenge management. OBSERVATIONS: The authors report the case of a 68-year-old male suspected to have a type I dural arteriovenous fistula based on magnetic resonance angiography and angiographic evaluation. He presented with progressive myelopathy and multiple neurological symptoms exacerbated by recent trauma. A superselective angiogram of the right T10 segmental artery suggested an intradural arteriovenous fistula; however, intraoperatively, the lesion was epidural. The arterialized venous structures were obliterated, and the patient reported significant postoperative symptomatic improvement. LESSONS: This case highlights the critical importance of comprehensive imaging and cautious interpretation in the diagnosis of spinal vascular malformations. It also underscores the need for a multidisciplinary approach to ensure accurate diagnosis and effective treatment. Surgeons must be prepared for intraoperative findings that diverge from preoperative imaging to adapt surgical strategies accordingly. Furthermore, this case contributes to the evolving understanding of eAVFs, suggesting that revised imaging protocols may be required to better distinguish epidural from intradural vascular abnormalities. https://thejns.org/doi/10.3171/CASE24331.

Comparison of a Novel Liquid Embolic System with Commonly Used Embolic Agents in the Endovascular Treatment of Intracranial Dural Arteriovenous Fistulas: A Single-Center Experience.

Background/Objectives: Endovascular embolization is an effective treatment option for cerebral arteriovenous malformation (AVM) and dural arteriovenous fistulas (DAVFs). The objective of this study was to assess the safety and efficacy of MenoxTM in patients with cranial dural arteriovenous fistulas. Methods: From January 2021 to January 2023, 19 patients with intracranial DAVFs underwent embolization procedures. All patients were treated by embolization with MenoxTM or/and in combination with other embolization products such as Onyx (Covidien, Irvine, California), PHIL (MicroVention, Tustin, California), and Squid (Balt Extrusion, Montmorency, France). Treatment approaches were selected depending on the anatomical location of the fistula. Patients were monitored and followed-up for 12 months. Results: The patients' mean age was 56.26 ± 16.49 years. Of these 19 patients, 58% (n = 11) were treated with the MenoxTM liquid embolizing agent (LEA) alone or in combination with different LEAs, while n = 7 were treated with other LEAs and 1 patient was treated solely with coils. Complete occlusion of DAVFs with MenoxTM and other agents was evident in 68.4% (n = 13/19) of patients. Complete occlusion (100%) was observed in the sinus rectus, transverse sinus, and diploic veins of the orbital roof, while complete occlusion was observed in 50% of falcotentorial patients and 60% of superior sagittal sinus patients. The lowest rate of complete fistula obliteration was observed in the dural carotid cavernous fistula (CCF) group (25%). An intra-procedural adverse event occurred in one patient. No other post-procedural adverse events were noted. Furthermore, in patients treated with MenoxTM, total occlusion was achieved in 72.7% (n = 8) of patients, whereas the non-MenoxTM group had 62.5% (n = 5) of patients with 100% occlusion and 37.5% (n = 3) of patients with subtotal occlusion. Conclusions: Outcomes using MenoxTM alone and in combination with other agents were effective, and it is safe for the treatment of dural arteriovenous fistulas.

Ruptured venous aneurysm associated with a dural arteriovenous fistula: Two case reports.

BACKGROUND: In general, venous aneurysm associated with dural arteriovenous fistula (dAVF) is considered to be developed under long standing venous hypertension and manifested as venous ectasia of draining vein itself. However, discrete saccular shaped venous aneurysm without angiographic evidence of venous hypertension arising from the draining vein, like cerebral arterial aneurysm, is quite rare and its pathomechanism remains unclear in patients with dAVF. CASE SUMMARY: In this report, we present two cases of ruptured saccular venous aneurysms associated with dAVF without venous hypertension or venous ectasia. In both cases, significant curve or stenosis is observed in draining vein, which is located in just distal portion of the venous aneurysms. These aneurysms were successfully treated with a transarterial embolization. Underlying mechanism of venous aneurysms in these cases is discussed. CONCLUSION: Although there is little doubt that hemodynamic stress has a critical role in the development of venous aneurysms in patients with dAVF, preceding venous hypertension or venous ectasia is not necessary for development and enlargement of venous aneurysms. Considering the significant risk of rupture, a careful review of draining vein features including tortuosity or stenosis is needed, especially in venous aneurysms without evidence of venous hypertension.

Endovascular embolization combined with anterior cervical corpectomy for treatment of cervical spinal dural arteriovenous fistula.

Background: The two main treatments for spinal dural arteriovenous fistula (SDAVF) include microsurgical occlusion or endovascular embolization (i.e., the latter alone has high recurrence rates). Here, we combined both strategies to treat/obliterate a cervical SDAVF more effectively. Case Description: A 34-year-old male presented with a marked decline in mental status attributed to an infratentorial subarachnoid hemorrhage. The left vertebral angiogram revealed a ruptured, low cervical SDAVF. He underwent successful occlusion of the spinal fistula utilizing super selective catheterization and endovascular embolization (i.e., utilizing Onyx-18 for the obliteration of target arteries). Due to significant SDAVF accompanying vessel recruitment/complex angioarchitecture, we additionally performed a C5 anterior corpectomy/fusion to afford direct access and complete surgical SDAVF occlusion. Three and 6 months later, repeated angiograms confirmed no recurrent or residual SDAVF. Conclusion: We successfully treated a low cervical SDAVF using a combination of endovascular embolization and direct surgical occlusion through an anterior C5 corpectomy with a fusion approach.

Recognition of dural to pial supply in high-grade dural arteriovenous fistula: A technical note.

High-grade dural arteriovenous fistulas (DAVFs) are known to demonstrate classical dural supply and can demonstrate pre-existing dural supply and 'pure' arterial supply from pial branches. The latter two are examples of congenital versus acquired pial to dural shunting, respectively. We describe the recognition of dural to pial supply during combined transarterial and transvenous embolization of a high-grade DAVF with holocephalic venous reflux, stressing the importance of careful assessment of this condition with micro catheter injections.

From Diagnosis to Complication: A Detailed Case Analysis on the Journey of Managing Medial Tentorial Dural Arteriovenous Fistula.

Tentorial dural arteriovenous fistulas (DAVFs) are rare but highly dangerous vascular anomalies, constituting a small percentage of all intracranial DAVFs. Despite their infrequency, these lesions display aggressive characteristics, frequently leading to hemorrhage or neurological deficits due to their retrograde drainage into leptomeningeal veins, thus classifying them as Borden type III lesions. This case presents a middle-aged man who suffered cerebellar and subarachnoid hemorrhages resulting from a medial tentorial DAVF. Initial imaging revealed a high-flow vascular lesion, which was subsequently confirmed through angiography. Endovascular embolization targeted the right middle meningeal artery, showing initial improvement. However, the patient experienced a notable decline two days later, attributed to residual or recurrent fistulas, venous hypertension, and cerebral edema. Effective management of tentorial DAVFs necessitates a multidisciplinary approach, combining endovascular, surgical, and occasionally radiosurgical techniques. Continuous monitoring is essential for early detection and management of complications. This case underscores the critical need for a comprehensive strategy to manage the high risks associated with these vascular anomalies and to prevent potentially life-threatening outcomes.

Angiographically occult spinal dural arteriovenous fistula diagnosed by exploratory surgery with intraoperative ultrasound: illustrative case.

BACKGROUND: A 78-year-old male presented with progressive myelopathic symptoms. The clinical course and imaging findings raised a high suspicion for venous hypertensive myelopathy due to a spinal dural arteriovenous fistula (SDAVF). OBSERVATIONS: Magnetic resonance angiography and four complete spinal angiograms did not reveal the presence of an SDAVF. Despite multiple negative angiograms, intraoperative ultrasound revealed abnormal cord edema and arterialized pulsatile vessels, confirming the presence of an SDAVF. The fistula was found and cauterized, which resulted in a decrease in the caliber of the dilated veins and an observed reduction of spinal cord stiffness posttreatment. The patient exhibited gradual improvement in neurological function. Retrospective analysis of the multiple complete spinal angiograms failed to reveal an anomaly at the treated level or any other level. LESSONS: This case underscores the diagnostic utility of intraoperative Doppler ultrasound and the importance of maintaining a high index of suspicion for SDAVF in cases with consistent clinical characteristics and a lack of alternative diagnoses, even with negative spinal angiography. https://thejns.org/doi/10.3171/CASE24438.

Comparative Volumetric Analyses Following Bevacizumab Therapy for a Patient With Concomitant Glioblastoma, Meningioma, and Dural Arteriovenous Fistula: A Case Report and Review of Literature.

Given that glioblastoma (GBM), meningioma (Mg), and dural arteriovenous fistula (dAVF) represent angiogenic diseases mainly caused by vascular endothelial growth factor (VEGF), bevacizumab (Bev) is expected to be effective against these diseases. We report a patient with concomitant GBM, Mg, and dAVF who was treated with neoadjuvant Bev, resulting in a reduction in the volume of GBM along with an improvement of clinical symptoms. An 85-year-old male presented with aphasia, gait disturbance, and dementia. Magnetic resonance imaging (MRI) showed a ring-enhanced intra-axial tumor with perifocal edema in the left temporal lobe, a dura-attached extra-axial tumor at the left sphenoid ridge, and dAVF at the left transverse-sigmoid sinus. Due to the age of the patient and low Karnofsky Performance Status (KPS) score, pharmacotherapy with a single dose of Bev was chosen over surgical resection. Three days after the Bev administration, aphasia and gait disturbance had dramatically improved. Volume reduction rates at one and five months after three administrations of Bev were 0.34% and 95.9% for GBM and 13.7% and 6.8% for meningioma, respectively. No significant change in dAVF was seen on digital subtraction angiography (DSA) during Bev therapy. VEGF concentration in GBM is known to be the highest among all types of brain tumors, including meningioma. VEGF might not play a pivotal role in the pathogenesis of dAVF. Based on this evidence from the present rare case with concomitant GBM, meningioma, and dAVF, responsiveness to Bev might depend on the level of VEGF expression.

Transvenous embolization of a Borden III middle cranial fossa dural arteriovenous fistula through the vein of Trolard and superficial middle cerebral vein: A technical case report.

Endovascular treatment for isolated dural arteriovenous fistula (DAVF) in the middle cranial fossa (MCF) with pure cortical venous drainage poses challenges, including the absence of a safe access route for transvenous embolization (TVE) and the risk of ischemia to neuro feeding vessels and dangerous anastomosis at the sphenoid wing. Therefore, surgical treatment involving direct blockage of venous reflux via craniotomy is typically preferred. We describe the case of a 63-year-old woman presented with generalized seizures and was diagnosed with a Borden III left MCF-DAVF. Initial TVE was unsuccessful due to an occluded inferior petrosal sinus and a lack of connection between the cavernous sinus and the shunt point. After reducing the shunt flow with transarterial embolization, retrograde TVE through cortical drainage enabled successful treatment for the DAVF. We used a triple coaxial system (4-French guiding sheath, 3.2-French intermediate distal access catheter, and 1.5-French microcatheter) to retrogradely navigate a microcathter from the right jugular vein through the superior sagittal sinus, the vein of Trolard, and into the superficial middle cerebral vein, ultimately achieving shunt occlusion using several coils. This case demonstrates that TVE for MCF-DAVFs with pure cortical venous drainage is feasible when a safe anatomical route is established using appropriate strategies and instruments and provides a safe and effective treatment option for similar cases.

How I do it: surgical ligation of posteromedial tentorial dural arteriovenous fistulas.

BACKGROUND: Tentorial dural arteriovenous fistulas (dAVFs) are categorized based on venous drainage and location. Although their angioarchitecture may initially appear intimidating, once "decodified," treatment is straightforward. Posteromedial tentorial dAVFs have an arterialized draining vein that emanates from the inferior tentorium along the posterior third of the straight sinus, just slightly off the midline. METHOD: With the aid of anatomical dissections, intraoperative photos, and operative videos, we outline the key steps for surgical treatment of posteromedial tentorial dAVFs. CONCLUSION: Posteromedial tentorial dAVFs constitute a precise and well-defined subtype of tentorial dAVF for which surgical ligation has an important role.

Dural arteriovenous fistula mimicking a stroke: A misdiagnosis of two months.

We present a case of a 70-year-old male who presented with left-sided weakness and dysarthria. Cranial imaging was suggestive of a cerebellar infarct and the patient was treated with aspirin and clopidogrel. Two months later a fall prompted further cranial imaging, which was concerning for an intracranial mass with vasogenic edema. Computed tomography angiogram (CTA) was negative for vascular lesion. Ultimately, a DSA revealed a Borden III dAVF between the right occipital artery and the posterior cerebellar vein that was treated with endovascular embolization.

Stereotactic radiosurgery for anterior cranial fossa dural arteriovenous fistulas.

OBJECTIVE: Anterior cranial fossa (ACF) dural arteriovenous fistulas (DAVFs) are notoriously malignant vascular abnormalities, and their drainage into the cortical vein poses a high risk of intracranial hemorrhage (ICH). Stereotactic radiosurgery (SRS) is increasingly seen as an alternative to microsurgery or embolization for the treatment of DAVFs; however, researchers have yet to report on its applicability to ACF DAVFs. This paper summarizes the authors' experience in the use of SRS for ACF DAVFs. The authors' objective was to gain a preliminary overview of SRS outcomes in the treatment of ACF DAVFs. METHODS: This retrospective study examined all patients who underwent SRS for ACF DAVFs at a single academic medical center between November 2000 and November 2023. Demographic data, DAVF characteristics, and clinical outcomes were obtained from medical records. RESULTS: A total of 12 patients diagnosed with ACF DAVFs were treated using SRS. One patient was lost to follow-up. The mean age was 54.8 years and men comprised 82% of the cohort. The most common presenting symptoms included headache (n = 5), ocular symptoms (n = 3), seizure (n = 2), anosmia (n = 1), and tinnitus (n = 1). Two patients were asymptomatic. Four patients (36%) initially presented with ICH. Nine patients exhibited DAVF Cognard type IV, and 2 patients exhibited Cognard type III. DAVF obliteration in 7 of the 11 patients (64%) was confirmed by brain MR angiography (n = 4) or digital subtraction angiography (n = 3). No post-SRS episodes of ICH were reported. Most of the patients (10 of 11) reported improvements in clinical symptoms. CONCLUSIONS: SRS appears to be a viable alternative treatment for ACF DAVFs, particularly for patients who are not suitable candidates for surgery or those with an unfavorable angioarchitecture.

Three-Dimensional Exoscope-Assisted Occlusion of a Foraminal Intradural Left L5-S1 Arteriovenous Fistula-Operative Video.

Spinal dural arteriovenous fistulas (dAVFs) are a rare type of spinal lesion that can cause severe clinical consequences.1 Early and accurate diagnosis and treatment are crucial to avoid severe complications such as radicular pain, weakness, sensory deficits, and loss of bowel and bladder control.2 Spinal dAVFs are commonly found in the lower thoracic or upper lumbar vertebrae. Spinal dAVFs are the most common spinal vascular malformations, of unknown cause, accounting for 70%-85 % of spinal shunts, with an annual incidence of 5-10 cases/1,000,000.3 Recently, they have been classified into extradural and intradural types, which may be further divided into dorsal and ventral lesions.4,5 Spine magnetic resonance imaging (MRI) is the most performed imaging study for suspected dAVF diagnosis.1 Catheter digital subtraction angiography (DSA) represents the gold-standard diagnosing technique. It provides critical information about the anatomy of the lesion, arterial inflow vessels, venous outflow, and endovascular treatment feasibility. DSA may also detect typical structures at risk during treatment.6 Surgical interruption of dAVF offers a complete cure, with low complication rates. Endovascular embolization might be safe and efficient, with high success rates, for selected vascular lesions.7,8 This video presents a rare case of left L5-S1 dAVF, surgically occluded with the aid of a three-dimensional (3D) exoscope (Video 1). There is little evidence about the application of the 3D exoscope in spinal vascular microsurgery, whereas it has been widely used and described in cranial surgery and spinal, degenerative, tumor, and traumatic surgery.9 In our experience, the advantages of this operating tool are the sharp color vividness, which allows adequate discrimination of anatomic structures, the distinct depth perception, the educational value for operating room attendants, and the ergonomics for surgeons. Ergonomics for surgeons, especially, is optimally adapted to spinal surgery, given the contraposed placement of surgeons and the disposition of screens during the operating procedure.

Efficacy of Transarterial Embolization Using Intermittent Flow Control for Tentorial Dural Arteriovenous Fistula Presenting as Myelopathy: A Technical Report.

BACKGROUND: Transarterial embolization (TAE) is generally the endovascular treatment of choice for tentorial dural arteriovenous fistula (dAVF). Although flow control of the feeder vessel has been reported to achieve complete shunt blockade, flow control in the absence of ischemia tolerance of internal carotid artery as a feeder has not been reported. We present a case in which treatment by Onyx TAE with intermittent flow control of the meningohypophyseal trunk as the feeder was successful for a tentorial dAVF presenting with myelopathy without tolerance of ischemia. METHODS: The intermittent flow control is presented for a tentorial dAVF presenting with myelopathy without tolerance for ischemia. An inflation of the balloon in the internal carotid artery was set for 5 minutes, and the Onyx injection was repeated at intervals of at least 2 minutes. Injections and pauses were repeated to allow Onyx to reach the shunt pouch. RESULTS: The patient underwent successful TAE with intermittent flow control for a tentorial dAVF presenting with myelopathy. The disappearance of the shunt was confirmed with gait disturbance resolution postoperatively. CONCLUSIONS: Intermittent flow control of the meningohypophyseal trunk using a balloon may be safe and effective for cases showing no tolerance for ischemia.

Pipeline embolization device as a standalone curative approach for recurrent sigmoid sinus DAVF.

Dural arteriovenous fistulas (dAVFs) can occur as complications after surgical procedures, especially following the resection of meningiomas near the dural sinus. This case report presents a 74-year-old male who developed a recurrent sigmoid dAVF following meningioma resection. Initially treated with transvenous embolization and middle meningeal artery embolization, the dAVF recurred with worsening clinical symptoms. Conventional treatment options, including sinus sacrifice and transarterial embolization, were unsuitable due to the critical role of the patient's dominant right sigmoid sinus in cerebral venous drainage. Consequently, a reconstructive approach was employed using a pipeline embolization device (PED) construct. The PED successfully occluded the dAVF while preserving the function of the sigmoid sinus. A follow-up angiogram confirmed stable occlusion and normalization of intracranial venous drainage. This case underscores the potential of flow diversion as a viable treatment option for dAVFs, particularly in scenarios where preserving venous sinus function is paramount.

Parasagittal dural arteriovenous fistulas.

BACKGROUND: The majority of studies on parasagittal dural arteriovenous fistulas (DAVFs) have been limited to case reports or case series, and they are frequently reported alongside true superior sagittal sinus (SSS) DAVFs. Because of the selective bias present in the reporting of dispersed small numbers of parasagittal DAVFs, the results of each study may influence the findings. As a result, we present a large sequential cohort of parasagittal DAVFs from our institution spanning a 20-year period. METHODS: This study was a retrospective analysis involving 80 patients with parasagittal DAVFs who were hospitalized at a single medical center from 2002 to 2022. We explore their clinical manifestations, angioarchitecture, clinical and radiographic outcomes. RESULTS: We identified 80 patients with 85 parasagittal DAVFs. The cohort consisted of 69 men and 11 women, with a M ± SD age of 50.5 ± 11.1 years. Seventy-six patients underwent trans-arterial embolization (TAE), two underwent surgery, and two received conservative treatment. Immediate complete occlusion was achieved in 74 cases (94.9%). Fifty (96.2%) patients were cured, with no recurrence detected on final follow-up imaging. One patient died 6 months after the final subtotal occlusion, while the other patients experienced improvement or resolution of clinical symptoms following treatment. CONCLUSIONS: These lesions carry a high risk of hemorrhage and nonhemorrhagic neurological deficits. In our series, TAE achieved a high cure rate for these lesions, with no major complications reported.

The surgical role of C1 nerve root identification for the disconnection of the spinal dural arteriovenous fistula at the craniocervical junction: a single center restrospective experience.

This study aims to discuss the identification of the C1 nerve root as an effective surgical approach to successfully locate the shunting point of craniocervical junction spinal dural arteriovenous fistula (CCJ-SDAVF) intraoperatively. This study included all patients with CCJ-SDAVF who underwent surgical treatment using the far-lateral transcondylar approach at a single institution from January 2017 to June 2023. Data on patient demographics, clinical and angiographic characteristics of CCJ-SDAVF, surgical details, and treatment outcomes were collected. Follow-up assessments were conducted for all patients until December 31, 2023. The study included a total of 7 patients, comprising 5 men(71.4%) and 2 women (28.6%), with an average age of 57.6 years. Among them, 4 patients (57.1%) developed diffuse subarachnoid hemorrhage(SAH), while 2 patients (28.6%) experienced progressive cervical myelopathy. The shunting points of all CCJ-SDAVFs, which exhibited engorged veins, were identified next to the C1 root. Complete obliteration of CCJ-SDAVFs was successfully achieved in all patients, as confirmed by postoperative angiography one month later. No recurrent CCJ-SDAVFs were observed two years after the operation. Among the patients, 5 (71.4%) experienced good functional recovery, as indicated by an mRS score ranging from 0 to 1, while the remaining 2 patients (28.6%) showed incomplete functional recovery. The surgical interruption of CCJ-SDAVFs is the preferred treatment option, given its high obliteration rate and favorable functional recovery outcomes. We advocate the identification of C1 spinal nerve root as a crucial surgical step to identify the shunting points of CCJ- SDAVFs.

Bailout using NBCA for incomplete onyx embolization of tentorial dural arteriovenous fistula.

Transarterial embolization using Onyx (Medtronic, Irvine, CA, USA) results in a high cure rate for complete obliteration of dural arteriovenous fistulas. However, incomplete obliteration occurs in some cases. Reports on the use of bailout therapy in such cases are limited. A 79-year-old man was diagnosed with Borden type III tentorial dural arteriovenous fistulas during a check-up for a headache. We first performed transarterial embolization with Onyx from a tentorial artery, but the fistula was not completely obliterated. We then performed an additional transarterial embolization with n-butyl-2-cyanoacrylate from the same artery in a single session, and the fistula was successfully bailed out, resulting in complete obliteration. Combining different liquid embolic materials, Onyx and n-butyl-2-cyanoacrylate, is an effective strategy for achieving complete obliteration in incomplete transarterial embolization treatment of dural arteriovenous fistulas.