First line direct access for transarterial embolization of a dural arteriovenous fistula: Case report and literature review

Alternative hybrid access in endovascular neurosurgery: Scoping review and technical considerations

BACKGROUND

The common femoral artery and radial artery constitute the most common access sites in contemporaneous endovascular neurosurgery. Oftentimes, it may be impossible to reach the vascular target safely due to different circumstances, necessitating alternative approaches. We aim to review these "last resource" access sites described in the literature, focusing on the technical aspects as a convenient reference.

METHODS

We performed a comprehensive literature search of PubMed capturing articles from 1958 to 2022.

RESULTS

We identified nine alternative approaches for endovascular access, after excluding direct carotid stick: superficial temporal artery access in 60 patients, calvarial foramina access in five patients, occipital artery access in seven patients, middle meningeal artery access in six patients, vertebral artery access in 23 patients and external carotid artery, internal maxillary artery, facial artery or lingual artery in 40 patients. Indications for the use of alternative access points included tortuous or occluded vessels, small vessel calibers, or anatomic variation. Pathologies treated included dural arteriovenous fistulas, arteriovenous malformations, intracranial aneurysms, acute stroke, and intracranial stenosis. Diagnostic brain angiograms were also performed.

CONCLUSIONS

Alternative vascular access routes expand the proceduralists' toolkit, enhancing the capability to manage complex cerebrovascular interventions. This review advocates for a broader understanding and consideration of these techniques, given their potential to significantly increase treatment options in neuroendovascular surgery.

A Comprehensive Analysis of Dural Arteriovenous Fistula Involving the Superior Sagittal Sinus: A Systematic Review

Objective

To evaluate published papers concerning dural arteriovenous fistula involving the superior sagittal sinus (SSS dAVF) treated with endovascular intervention.

Methods

A literature review was performed to identify studies reporting the clinical characteristics, vascular anatomy, endovascular techniques, embolic materials, angiographical result, and outcomes of SSS dAVF.

Results

The analysis consisted of 40 case reports or series, comprising a total of 51 cases of SSS dAVF treated with endovascular intervention. Clinical symptoms included hemorrhage (29.4%), infarction (17.6%), and seizure (7.8%). The arterial supply included the middle meningeal artery (MMA) (100%), superficial temporal artery (STA) (62.7%), and occipital artery (OA) (49.0%). Bilateral MMAs supplied in 78.4% of the cases. A pial arterial supply was observed in 21.6% of the cases. Stenosis or occlusion of the sinus was seen in 37.3% of the cases. The distribution of the Borden classification was as follows: I (7.8%), II (37.3%), and III (54.9%). The endovascular techniques were transvenous embolization (TVE) alone (11.8%), transarterial embolization (TAE) alone (74.5%), and a combination thereof (13.7%). The types of embolic materials for TAE were a coil (25.5%), n-butyl-2-cyanoacrylate (NBCA) (33.3%), and Onyx (45.1%). The arterial pedicles for TAE included MMA (86.3%), STA (17.6%), and OA (9.8%). Direct surgical exposure for the alternative endovascular access was performed to the SSS (5.9%), MMA (3.9%), STA (5.9%), and OA (3.9%). Sinus angioplasty with or without stenting was done in 9.8% of the cases. Balloon-assisted Onyx TAE was done with proximal flow control (7.8%), collateral devascularization (5.9%), and sinus protection (3.9%). Complete occlusion was achieved in 86.3% of the cases while the number of endovascular sessions varied among patients: single (74.5%), double (15.7%), and triple (9.8%). The rate of a postoperative modified Rankin Scale (mRS) score of 0-2 was 89.3%, with morbidity and mortality rates of 7.8% and 3.9%, respectively. Two patients died, possibly due to postoperative acute SSS occlusion.

Conclusion

The current systematic review disclosed several specific results, namely, the angioarchitectures of the SSS dAVF, the relationship between classification and hemorrhagic presentation, the diversity of treatment techniques, the association between the complete occlusion rate and the SSS condition, and the difficulty of achieving curable occlusion in a single session. These findings underscore the need for the development of endovascular techniques and devices to treat this challenging lesion. Improvements in adjunctive endovascular procedures, such as balloon-assisted techniques for Onyx TAE, may help support to the safe and effective obliteration of SSS dAVF.