How do you identify dysplastic pial arterial supply originating from pial arteries in a dural arteriovenous fistula (DAVF) supplied by dural branches of a pial vessel?

From the Guidelines

To identify dysplastic pial arterial supply originating from pial arteries in a dural arteriovenous fistula (DAVF) supplied by dural branches of a pial vessel, arteriography is the most appropriate diagnostic tool, as it provides high sensitivity and specificity for detecting arteriovenous shunts, including DAVFs, as noted in the 2023 update of the ACR Appropriateness Criteria for tinnitus 1. When evaluating a DAVF, it is crucial to distinguish between dysplastic pial arterial supply and dural branches of a pial vessel to guide treatment decisions.

• Key characteristics of dysplastic pial arteries include a tortuous, corkscrew appearance and a course that follows the brain surface, as opposed to dural branches that tend to course within the dura mater.
• The arterial territory is also an important factor, with pial arteries supplying brain parenchyma and demonstrating parenchymal blush on angiography, whereas dural branches primarily supply the meninges.
• The timing of contrast opacification is critical, with dysplastic pial feeders filling during the arterial phase of cerebral circulation, while dural branches typically opacify earlier.
• Selective microcatheterization with superselective angiography can help differentiate these vessels by demonstrating their distal supply patterns, as discussed in the context of arteriovenous shunts detection 1.
• Understanding the venous drainage patterns is also vital, as pial arterial supply often leads to cortical venous drainage, which increases the risk of hemorrhage. Given the importance of accurate diagnosis for treatment planning, arteriography remains the gold standard for identifying dysplastic pial arterial supply in DAVFs, especially when non-invasive tests like CTA and MRA are inconclusive 1.

From the Research

Identifying Dysplastic Pial Arterial Supply

To identify dysplastic pial arterial supply originating from pial arteries in a dural arteriovenous fistula (DAVF) supplied by dural branches of a pial vessel, several factors should be considered:

• The presence of pial arterial supply may be a risk factor for intraoperative hemorrhage during transarterial embolization of DAVF through dural feeders 2
• Identification of pial feeders and early superselective occlusion of such feeders are important for safe management 2
• Advancing microcatheter tips as close to the fistula point as possible and remaining highly aware of potential embolizer flow back into the pial artery are key factors in achieving successful embolization 3
• Supratentorial draining direction may be a risk factor for venous ectasia and subarachnoid hemorrhage in petrous apex DAVFs with pial arterial supplies 4

Diagnostic Considerations

Diagnostic considerations for identifying dysplastic pial arterial supply include:

• Brain magnetic resonance imaging, computed tomography, angiography, and clinical outcomes can provide valuable information for diagnosis and treatment planning 3
• Comprehensive angiographic and intraoperative images can support technical emphasis and individual case presentation 5
• Endovascular treatment, surgical resection, and stereotactic radiosurgery are treatment options for dural and pial fistulas, with emphasis on endovascular treatment 6

Treatment Implications

Treatment implications for dysplastic pial arterial supply include:

• Microsurgical disconnection can result in complete fistula obliteration without evidence of recurrence on follow-up imaging 5
• A combined approach involving partial preoperative embolization can potentially decrease surgical morbidity 5
• Balloon-assisted embolization may be an option for treating TDAVFs with pial arterial supplies in the future 3