Combined open surgery and endovascular embolization for a ruptured sphenoid wing dural arteriovenous fistula.

BACKGROUND: The sphenoid wing dural arteriovenous fistula (AVF) is rare, and can manifest with severe symptoms, particularly in cases classified as greater sphenoid wing type. Endovascular therapy is generally employed, however, open surgical intervention could be warranted in cases with complex fistula. METHOD: We present a case with ruptured greater sphenoid wing dural AVF (Cognard type IV), in which endovascular embolization using liquid material was performed, followed by open surgery to concurrently disconnect the fistula and evacuate the hematoma. CONCLUSION: The sphenoid wing dural AVFs may be effectively cured by open surgery for fistula disconnection in conjunction with endovascular embolization.

Treatment of Ethmoidal Dural Arteriovenous Fistulae Using Supraorbital Keyhole Subfrontal Approach.

Due to a unique cortical venous drainage pattern without sinus drainage, ethmoidal dural arteriovenous fistula (DAVF) are uncommon cerebral vascular lesions that carry a high risk of brain bleeding and neurologic deficit. Surgical intervention has been found to have a lower complication rate and a more satisfactory obliteration rate than endovascular treatment among the various DAVF treatment options. The supraorbital keyhole subfrontal approach is one of the least invasive and appropriate surgical techniques for addressing the anterior fossa vascular lesion in eDAVFs. We describe two men, ages 60 and 71, who underwent this surgical intervention to treat asymptomatic Cognard type IV eDAVFs. Complete obliteration with a detached fistulous point and skeletonization was accomplished with the aid of intraoperative neuronavigation. Thus, we suggest that a suitable surgical method for the treatment of eDAVFs would be to use a supraorbital keyhole subfrontal approach.

Dural arteriovenous fistulas in the falx cerebri: case series and literature review.

Dural arteriovenous fistulas (DAVFs) within the falx cerebri are infrequently documented and may be linked with the falcine sinus/venous plexus. The falcine sinus/venous plexus, often regarded as a normal venous structure, can exhibit pathological characteristics, differing from the persistent fetal falcine sinus. A retrospective analysis was conducted at a single center to identify all cases of DAVFs within the falx cerebri spanning from 2002 to 2022. Demographic data, fistula features, treatment modalities, clinical outcomes, and fistula closure were collected and analyzed. Additionally, relevant literature on DAVFs in this location was reviewed. Ten cases were identified at our center, supplemented by 13 cases reported in the literature. In our cohort, patients had an average age of 49.4 ± 8.1 years, with a male predominance of 90%. Trans-arterial embolization (TAE) alone achieved immediate complete occlusion in eight cases, while conservative treatment was pursued in two cases. No treatment-related complications or fistula recurrences were observed. In the literature, seven patients underwent direct surgery, three underwent TAE, and one underwent both direct surgery and radiosurgery for complete fistula closure. No instances of fistula recurrence or treatment complications were reported. Dural arteriovenous fistulas within the falx cerebri are rare, with limited literature available. They typically present as aggressive lesions. Treatment options include direct surgery or TAE. However, due to a lack of long-term DSA follow-up, the cure and recurrence rates are unknown for endovasdcular therapy. Further investigation is warranted to elucidate the involvement of the falcine sinus/venous plexus in falx cerebri DAVFs.

Surgery versus endovascular treatment for spinal dural arteriovenous fistulas: a multicenter experience and systematic literature review.

Surgery and endovascular therapy are the primary treatment options for spinal dural arteriovenous fistula (SDAVF). Due to the absence of a consensus regarding which therapy yields a superior outcome, we conducted a comparative analysis of the surgical and endovascular treatment of SDAVF through a multicenter case series and a systematic literature review. Patients with SDAVF, surgically or endovascularly treated at four neurosurgical centers from January 2001 to December 2021, were included in this study. Level of SDAVF, primary treatment modality, baseline and post-procedural neurological status were collected. The primary outcomes were failure, complication rates, and a newly introduced parameter named as therapeutic delay. A systematic review of the literature was performed according to PRISMA-P guidelines. The systematic review identified 511 papers, of which 18 were eligible for analysis, for a total of 814 patients, predominantly male (72%) with a median age of 61 and mainly thoracic SDAVFs (65%). The failure rate was significantly higher for endovascular therapy (20%) compared to surgery (4%) (p < 0.01). Neurological complications were generally rare, with similar rates among the two groups (endovascular 2.9%; surgery 2.6%). Endovascular treatment showed a statistically significantly higher rate of persistent neurological complications than surgical treatment (2.9% versus 0.2%; p < 0.01). Both treatments showed similar rates of clinical improvement based on Aminoff Logue scale score. The multicenter, retrospective study involved 131 patients. The thoracic region was the most frequent location (58%), followed by lumbar (37%). Paraparesis (45%) and back pain (41%) were the most common presenting symptoms, followed by bladder dysfunction (34%) and sensory disturbances (21%). The mean clinical follow-up was 21 months, with all patients followed for at least 12 months. No statistically significant differences were found in demographic and clinical data, lesion characteristics, or outcomes between the two treatment groups. Median pre-treatment Aminoff-Logue score was 2.6, decreasing to 1.4 post-treatment with both treatments. The mean therapeutic delay for surgery and endovascular treatment showed no statistically significant difference. Surgical treatment demonstrated significantly lower failure rates (5% vs. 46%, p < 0.01). In the surgical group, 2 transient neurological (1 epidural hematoma, 1 CSF leak) and 3 non-neurological (3 wound infections) complications were recorded; while 2 permanent neurological (spinal infarcts), and 5 non-neurological (inguinal hematomas) were reported in the endovascular group. According to the literature review and this multicenter clinical series, surgical treatment has a significantly lower failure rate than endovascular treatment. Although the two treatments have similar complication rates, endovascular treatment seems to have a higher rate of persistent neurological complications.

Preoperative Angiographic Protocol for the Surgical Management of Spinal Dural Arteriovenous Fistulas: A Technical Nuance for Safe Minimally Invasive Surgery.

BACKGROUND: Interruption of the fistulous point is the goal of treatment of spinal dural arteriovenous fistulas (dAVFs). Microsurgery remains a highly efficient treatment in terms of complete occlusion with the lowest risk of recurrence rate. It is reported that the hardest step involves finding the fistulous site itself, potentially extending surgical access and time and increasing potential postoperative surgical-related complications. The accurate preoperative detection of the shunt and spinal level together is crucial for guiding optimal, fast, and safe microsurgical treatment. METHODS: We describe a preoperative angiographic protocol for achieving a safe and simple resection of spinal dural arteriovenous fistulas based on a 6-year institutional experience of 42 patients who underwent minimally invasive procedures. Two illustrative cases are included to support the technical descriptions. RESULTS: The suspected artery associated with the vascular malformation of interest is studied in our angiographic protocol through nonsubtracted selective acquisitions in lateral projection. The resulting frames are reconstructed with three-dimensional rotational angiography. The implementation of the preoperative angiographic protocol allowed 100% of intraoperative identification of the fistulous point in all cases with the use of a minimally invasive approach. CONCLUSIONS: Nowadays, neurosurgeons advocate for minimally invasive procedures and procedures with low morbidity risk for treatment of spinal dural arteriovenous fistulas. Our preoperative approach for accurate angiographic localization of the fistulous point through nonsubtracted and three-dimensional reconstructed angiography allowed us to achieve safe and definitive occlusion of the shunt.

[Angioarchitecture and Associated Dural Arteriovenous Fistulas of the Superior Petrosal Sinus and Petrosal Vein].

The superior petrosal sinus and petrosal vein are important drainage routes for the posterior cranial fossa, with some variations and collateral vessels. An anterolateral-type tentorial dural arteriovenous fistula, which occurs around the petrosal vein, often develops aggressive symptoms due to venous reflux to the brainstem and cerebellum. Neuroendovascular treatment of this fistula is usually challenging because transarterial embolization has a high risk and indications for transvenous embolization are limited. In the cavernous sinus and transverse sinus/sigmoid sinus dural arteriovenous fistulas, venous reflux to the petrosal vein is dangerous, and a treatment strategy with the occlusion of the petrosal vein is indispensable. Furthermore, attention should be paid to venous approaches through the superior petrosal sinus.

[Transverse Sinus / Sigmoid Sinus].

The transverse sinus(TS)and sigmoid sinus(SS)are common sites for dural arteriovenous fistulas, and an understanding of vascular anatomy is important when developing treatment strategies. In recent years, transarterial embolization, with a liquid embolization material, has become the treatment of choice, preserving the sinus without extensive coil filling of the affected sinus. With this expansion of therapeutic options, we feel that an understanding of the microanatomy has become more important. For example, the exact site where the vein of Labbé joins the TS should be determined. This article focuses on the development and anatomy of the TS and SS and makes points that should be considered when treating dural arteriovenous fistulas.

Dural Arteriovenous Fistula.

Dural arteriovenous fistulas are rare cerebrovascular lesions arising from abnormal connections between an artery and a vein. Though rare, high-grade aggressive lesions can cause hemorrhagic events and non-hemorrhagic neurologic deficits if left untreated. Treatment options vary based on angioarchitecture, location, and patient characteristics and range from conservative observation to palliative treatment, radiosurgery, endovascular embolization, and open surgery. The main goal of treatment is to obliterate flow through the abnormal connection and prevent further arterial flow to the venous system.

The role of surgical disconnection for posterior fossa pial arteriovenous fistulas and dural fistulas with pial supply: an illustrative case series.

BACKGROUND: Pial arteriovenous fistulas (pAVFs) are rare vascular malformations characterized by high-flow arteriovenous shunting involving a cortical arterial supply directly connecting to venous drainage without an intermediate nidus. Dural arteriovenous fistulas (dAVFs) can infrequently involve additional pial feeders which can introduce higher flow shunting and increase the associated treatment risk. In the posterior fossa, arteriovenous fistula (AVF) angioarchitecture tends to be particularly complex, involving either multiple arterial feeders-sometimes from both dural and pial origins-or small caliber vessels that are difficult to catheterize and tend to be intimately involved with functionally critical brainstem or upper cervical cord structures. Given their rarity, published experience on microsurgical or endovascular treatment strategies for posterior fossa pAVFs and dAVFs with pial supply remains limited. METHODS: Retrospective chart review from 2019-2023 at a high-volume center identified six adult patients with posterior fossa pAVFs that were unable to be fully treated endovascularly and required microsurgical disconnection. These cases are individually presented with a technical emphasis and supported by comprehensive angiographic and intraoperative images. RESULTS: One vermian (Case 1), three cerebellopontine angle (Cases 2-4) and two craniovertebral junction (Cases 5-6) posterior fossa pAVFs or dAVFs with pial supply are presented. Three cases involved mixed dural and pial arterial supply (Cases 1, 4, and 6), and one case involved a concomitant microAVM (Case 2). Endovascular embolization was attempted in four cases (Cases 1-4): The small caliber and tortuosity of the main arterial feeder prevented catheterization in two cases (Cases 1 and 3). Partial embolization was achieved in Cases 2 and 4. In Cases 5 and 6, involvement of the lateral spinal artery or anterior spinal artery created a prohibitive risk for endovascular embolization, and surgical clip ligation was pursued as primary management. In all cases, microsurgical disconnection resulted in complete fistula obliteration without evidence of recurrence on follow-up imaging (mean follow-up 27.1 months). Two patients experienced persistent post-treatment sensory deficits without significant functional limitation. CONCLUSIONS: This illustrative case series highlights the technical difficulties and anatomical limitations of endovascular management for posterior fossa pAVFs and dAVFs with pial supply and emphasizes the relative safety and utility of microsurgical disconnection in this context. A combined approach involving partial preoperative embolization-when the angioarchitecture is permissive-can potentially decrease surgical morbidity. Larger studies are warranted to better define the role for multimodal intervention and to assess associated long-term AVF obliteration rates in the setting of pial arterial involvement.

Direct superior sagittal sinus puncture via a surgical burr hole for curative embolization of the complex transverse-sigmoid sinus dural arteriovenous fistula: How I do it.

BACKGROUND: Transvenous embolization of high-grade dural arteriovenous fistulas (dAVFs) is challenging particularly when the direct sinus access is favorable due to the complex venous anatomy which prohibits endovascular access via the transfemoral approach. METHOD: The procedure was conducted in the hybrid operating suite, where a burr hole was performed, followed by direct catheterization of the superior sagittal sinus. Coil embolization was then executed to achieve complete obliteration of the fistula. CONCLUSION: The direct puncture of the superior sagittal sinus is a safe and effective method for treating complex dAVFs. This approach grants access to the fistula channel which facilitates curative embolization.

Clinical and radiological features of parasagittal dural arteriovenous fistulas: a report of 8 cases from a single institution.

OBJECTIVE: Dural arteriovenous fistulas (dAVFs) of the superior sagittal sinus (SSS) are uncommon and represent 5%-12% of all intracranial dAVFs. SSS dAVFs can be divided into two main subtypes. The first type involves direct arterialization of the SSS, whereas the second type consists of a parasagittal arteriovenous shunt draining into a cortical vein directly lateral to the SSS and has retrograde cortical venous drainage with only secondary involvement of the SSS. Descriptions of the latter type of SSS dAVF are limited. As such, the authors present a consecutive case series of parasagittal SSS dAVFs from their institution. They detail clinical presentation, treatment strategies, and clinical and radiographic outcomes. METHODS: The authors retrospectively reviewed a prospectively collected database of dAVFs that were treated between 2017 and 2023. All dAVFs characterized by an arterialized parasagittal vein directly lateral to the SSS were included in this study. Baseline demographic, clinical, radiological, treatment, and outcome-specific variables of interest were abstracted. RESULTS: One hundred fifty-four dAVFs were seen at the authors' institution over the 6-year period of interest. Eight (5.2%) were parasagittal dAVFs. At initial diagnostic imaging, 7 were Cognard grade III and 1 was grade IV. All patients initially underwent embolization of their dAVF. Three patients did not have complete obliteration of their dAVF after the first embolization. One patient underwent further treatment with repeat embolization, and 1 underwent microsurgical disconnection-both resulted in complete occlusion of the dAVF. Seven dAVFs were obliterated at final follow-up and 1 remained patent as the patient refused further treatment despite angiographic progression of dAVF. All symptomatic patients had resolution of their symptoms, and the average length of follow-up was 16.8 months. CONCLUSIONS: Treatment of parasagittal dAVFs consists of occluding the proximal portion of the parasagittal arterialized draining vein. Endovascular therapy with liquid embolic agents is usually the first line of treatment. Surgical ligation is a valid option if the fistula cannot be successfully obliterated with embolization. Symptoms related to the SSS dAVF resolve after their obliteration.

Stereotactic radiosurgery with versus without embolization for intracranial dural arteriovenous fistulas: a systematic review and meta-analysis.

OBJECTIVE: Stereotactic radiosurgery (SRS) has been established as a safe and alternative treatment for dural arteriovenous fistulas (dAVFs). While embolization alone is the most commonly used modality for the treatment of dAVFs, the adjunctive use of embolization with SRS, with the growing use of SRS, has gained increasing interest in the past few years. However, the relative efficacy and safety of SRS combined with embolization versus SRS alone for dAVFs remains uncertain. Hence, this systematic review aimed to evaluate the efficacy of SRS with adjunctive embolization for intracranial dAVFs. METHODS: A systematic review and meta-analysis was conducted by searching electronic databases, including PubMed, Embase, and the Cochrane Library, up to August 2023. All studies evaluating the utilization of adjunctive embolization and SRS for dAVFs were included. Risk of bias was assessed using the Newcastle-Ottawa Scale. A meta-analysis was conducted on the suitable outcomes. RESULTS: Eighteen studies involving 715 patients were included. The mean age of the participants in the study was 64.30 years in the adjunctive embolization group and 60.51 years in the SRS-alone group. In the adjunctive embolization group 41.3% of patients were female, compared with 47.1% in the SRS-only group. The dAVF obliteration rates were 64.7% and 65.7% in the adjunctive embolization and SRS-alone groups, respectively. These obliteration rates were comparable between the two groups (p = 0.96), as were the symptom improvement rates (p = 0.35). Adverse events were rare, and were more commonly associated with the adjunctive embolization procedure, although further causal analysis was not possible. CONCLUSIONS: This study provides evidence that adjunctive embolization plus SRS provides similar obliteration and symptom improvement rates compared with SRS alone, with both having very limited SRS-related adverse events. Considering the added burden and adverse events of additional endovascular treatment, the authors recommend embolization be reserved for more complex dAVFs or when embolization can potentially be curative alone or provide more rapid symptomatic relief or protection during the radiosurgical latency period.

Digital exoscope versus surgical microscope in spinal dural arteriovenous fistula surgery: a comparative series.

OBJECTIVE: Surgical treatment of spinal dural arteriovenous fistulas (DAVFs) has been reported to be superior to endovascular treatment in terms of occlusion of the fistula. Despite the increased availability of digital 3D exoscopes, the potential benefits of using an exoscope in spinal DAVF surgery have not been studied. The purpose of this study was to report and compare the results of exoscope- and microscope-assisted surgery for spinal DAVFs. METHODS: All consecutive adult patients (≥ 18 years of age) treated surgically for spinal DAVFs from January 2016 to January 2023 in a tertiary neurosurgical referral center were included. All patients were operated on by one neurosurgeon. Their pre- and postoperative clinical findings, imaging studies, and intra- and postoperative events were evaluated and surgical videos from the operations were analyzed. RESULTS: Altogether, 14 patients received an operation for spinal DAVF during the study period, 10 (71%) with an exoscope and 4 (29%) with a microscope. The DAVFs were most commonly located in the lower parts of the thoracic spine in both groups. The duration of exoscopic surgeries was shorter (141 vs 151 minutes) and there was less blood loss (60 vs 100 ml) than with microscopic surgeries. No major surgical complications were observed in either group. Of the 14 patients, 10 had gait improvement postoperatively: 7 (78%) patients in the exoscope group and 3 (75%) in the microscope group. None of the patients experienced deterioration following surgery. CONCLUSIONS: Exoscope-assisted surgery for spinal DAVFs is comparable in safety and effectiveness to traditional microscopic surgery. With practice, experienced neurosurgeons can adapt to using the exoscope without major additional risks to the patient.

Comparison between endovascular and surgical treatment of spinal dural arteriovenous fistulas: a single-center cohort and systematic review.

OBJECTIVE: With recent advancements in minimally invasive techniques, endovascular embolization has gained popularity as a first-line treatment option for spinal dural arteriovenous fistulas (sDAVFs). The authors present their institution's case series of sDAVFs treated endovascularly and surgically, and they performed a systemic review to assess the outcomes of both modalities of treatment. METHODS: The authors conducted a retrospective observational study of 24 consecutive patients with sDAVFs treated between 2013 and 2023. The primary outcome was the rate of occlusion, which was compared between the surgically and endovascularly treated sDAVFs. They also conducted a systemic review of all the literature comparing outcomes of endovascular and surgical treatment of sDAVFs. RESULTS: A total of 24 patients with 24 sDAVFs were studied. The mean patient age was 63.8 ± 15.5 years, and the majority of patients were male (n = 19, 79.2%). Of the 24 patients, 8 (33.3%) received endovascular treatment, 15 (62.5%) received surgical treatment, and 1 (4.2%) patient received both. Complete occlusion at first follow-up was higher in the surgical cohort but did not achieve statistical significance (66.7% vs 25%, p = 0.52). Recurrence was higher in the endovascular cohort (37.5% vs 13.3%, p = 0.3), while the rate of postprocedural complications was higher in the surgical cohort (13.3% vs 0%, p = 0.52); however, neither of these differences was statistically significant. CONCLUSIONS: Endovascular embolization in the management of sDAVFs is an alternative treatment to surgery, whose long-term efficacy is still under investigation. These findings suggest overall comparable outcomes between endovascular and open surgical treatment of sDAVFs. Future studies are needed to determine the role of endovascular embolization in the overall management of sDAVFs.

The negative impact of treatment delays on the long-term neurological outcomes of spinal dural arteriovenous fistulas: a longitudinal cohort study.

OBJECTIVE: Dural arteriovenous fistulas are rare vascular malformations that affect the brain and spinal cord. Spinal dural arteriovenous fistulas (sdAVFs) are the most frequently encountered vascular malformation affecting the spinal cord. The object of this study was to evaluate the impact of treatment delays on the long-term neurological outcomes of either open surgical or interventional treatment of sdAVFs. METHODS: In this retrospective, population-based cohort study, the authors examined consecutive patients with diagnosed sdAVFs at a tertiary care center between 2005 and 2020. Patients were assessed using the Aminoff-Logue disability scale (ALS) at various time points including symptom onset, primary care visit, first specialist outpatient visit, as well as both short and long-term follow-ups. The postoperative long-term ALS gait and bladder grades constituted the primary outcomes of the study. RESULTS: Among the 34 patients included in the study, the median age was 65 years, and there was a male predominance (71%). Most lesions were in the lumbar region (47%). Significant worsening in ALS gait and bladder grades was observed preoperatively, followed by postoperative improvements (p < 0.05). There was no difference in outcomes between surgical and endovascular treatments. Older age (OR 1.10, 95% CI 1.03-1.17, p = 0.007), worse preoperative ALS gait grades (OR 5.12, 95% CI 2.18-12.4, p < 0.001), and longer time from first specialist outpatient visit to first treatment (OR 1.00, 95% CI 1.00-1.01, p = 0.040) were independently associated with worse long-term gait outcomes. Only the preoperative ALS bladder score was a predictor of worse long-term bladder function (OR 92.7, 95% CI 28.0-306.7, p < 0.001). CONCLUSIONS: Both surgical and endovascular treatments for sdAVFs led to significant neurological improvements. However, treatment delays were associated with less favorable long-term outcomes. Prompt diagnosis and early intervention prior to symptom progression may enhance recovery and help to preserve neurological function.

Long-term treatment outcomes and natural course of low-grade intracranial dural arteriovenous fistulas.

OBJECTIVE: In contrast to high-grade dural arteriovenous fistula (dAVF), low-grade dAVF is mainly associated with tinnitus and carries a low risk of morbidity and mortality. It remains unclear whether the benefits of active interventions outweigh the associated risk of complications in low-grade dAVF. METHODS: The authors conducted a retrospective single-center study that included all consecutive patients diagnosed with an intracranial low-grade dAVF (Cognard type I and IIa) during 2012-2022 with DSA. The authors analyzed symptom relief, symptomatic angiographic cure, treatment-related complications, risk for intracerebral hemorrhage (ICH), and mortality. All patients were followed up until the end of 2022. RESULTS: A total of 81 patients were diagnosed with a low-grade dAVF. Of these, 48 patients (59%) underwent treatment (all primary endovascular treatments), and 33 patients (41%) did not undergo treatment. Nine patients (19%) underwent retreatments. Angiographic follow-up was performed after median (IQR) 7.7 (6.1-24.1) months by means of DSA (mean 15.0, median 6.4 months, range 4.5-83.4 months) or MRA (mean 29.3, median 24.7 months, range 5.9-62.1 months). Symptom control was achieved in 98% of treated patients after final treatment. On final angiographic follow-up, 73% of patients had a completely occluded dAVF. There were 2 treatment-related complications resulting in 1 transient (2%) and 1 permanent (2%) neurological complication. One patient showed recurrence and progression of a completely occluded low-grade dAVF to an asymptomatic high-grade dAVF. No cases of ICH- or dAVF-related mortality were found in either treated patients (median [IQR] follow-up 5.1 [2.0-6.8] years) or untreated patients (median [IQR] follow-up 5.7 [3.2-9.0] years). CONCLUSIONS: Treatment of low-grade dAVF provides a high rate of symptom relief with small risks for complications with neurological sequela. The risks of ICH and mortality in patients with untreated low-grade dAVF are minimal. Symptoms may not reveal high-grade recurrence, and radiological follow-up may be warranted in selected patients with treated low-grade dAVF. An optimal radiographic follow-up regimen should be developed by a future prospective multicenter registry.

Treatment outcomes and the role of the DES scheme in the appropriate treatment selection for high-grade dural arteriovenous fistulas.

OBJECTIVE: Endovascular and microsurgical treatment are viable options for the majority of Borden type III dural arteriovenous fistulas (dAVFs). The aim of this study was to examine treatment outcomes in a comparative analysis of endovascular and surgical treatment modalities for Borden type III fistulas and explore clinical implications of the DES scheme in selecting ideal candidates for surgical therapy. METHODS: Patients diagnosed with dAVFs with leptomeningeal venous drainage admitted to the Departments of Neurosurgery or Neuroradiology of the University Hospital Zurich between January 2014 and October 2021 were included in this study. Comprehensive patient data including demographics, clinical presentation, and dAVF characteristics, including established classifications, were collected. Treatment outcomes were assessed based on postinterventional angiography findings. In addition, treatment-related complications were assessed based on the Clavien-Dindo classification. RESULTS: Among all Borden type III dAVFs, 15 were initially treated endovascularly (60% complete occlusion rate) and 10 with microsurgical disconnection (90% complete occlusion rate) (p = 0.18). Subgroup analysis of dAVFs meeting the criteria for directness and exclusivity based on the DES scheme showed a 100% complete occlusion rate after microsurgical disconnection, whereas embolization achieved a complete occlusion rate of 60% (p = 0.06). There was no significant difference in the rate or severity of treatment-related complications between treatment modalities. CONCLUSIONS: This study suggests that microsurgical disconnection is a viable primary treatment modality for Borden type III dAVFs, particularly for dAVFs that meet the criteria of directness and exclusivity according to the DES scheme. The DES scheme demonstrates its relevance in selecting the most appropriate treatment strategy for affected patients.