Pediatric traumatic dural arteriovenous fistula

BACKGROUND

Dural arteriovenous fistulas are uncommon lesions in children, with traumatic lesions suspected to arise from incomplete arterial injury in proximity to a vein or draining sinus. Management of symptomatic acquired lesions requires evaluation of patient presentation, neurological status, and pathoanatomic configuration, with special consideration required for surgery secondary to failed endovascular technique.

CASE REPORT

A 12-year-old male sustained a bicycle fall causing a right temporo-parietal skull fracture associated with non-surgical right epidural hematoma and left contre-coup parietal contusion. Six-weeks later, he complained of a right temporal bruit with subsequent cerebral angiography demonstrating a dural-based fistula between the right middle meningeal artery and a dural vein draining into the sigmoid sinus.

INTERVENTION

Endovascular treatment of this lesion with glue embolization and coiling was unsuccessful, with angiographic illustration of previously unobserved collateral vessels and coils occupying the sigmoid sinus. A right temporo-parietal craniectomy was required to excise the dural-based fistula, followed by dural defect repair with bovine pericardium and subsequent cranioplasty. Six years later the patient remains neurologically intact with no headaches or bruit.

CONCLUSIONS

Dural arteriovenous fistula can uncommonly occur following traumatic injury in children. Partial injury to the middle mengineal artery may have established arterial communication with the draining vein that became ectatic and tortuous under high pressure. Failure of primary endovascular treatment may complicate secondary surgical intervention.

The putative role of the venous system in the genesis of vascular malformations

Recent clinical and experimental evidence has challenged the traditional concept of the venous system as a “passive” element in the genesis and evolution of intracranial vascular malformations. The authors review the clinical and experimental evidence linking the venous system and its anomalies to the genesis of various intracranial vascular malformations, including dural arteriovenous fistulas, cavernous malformations, parenchymal arteriovenous malformations, and capillary telangiectasia. They also describe the potential significance of different associations of these vascular anomalies.

Cranial dural arteriovenous fistulas: modification of angiographic classification scales based on new natural history data

This article presents a modification to the existing classification scales of intracranial dural arteriovenous fistulas based on newly published research regarding the relationship of clinical symptoms and outcome. The 2 commonly used scales, the Borden-Shucart and Cognard scales, rely entirely on angiographic features for categorization. The most critical anatomical feature is the identification of cortical venous drainage (CVD; Borden-Shucart Types II and III and Cognard Types IIb, IIa + b, III, IV, and V), as this feature identifies lesions at high risk for future hemorrhage or ischemic neurological injury. Yet recent data has emerged indicating that within these high-risk groups, most of the risk for future injury is in the subgroup presenting with intracerebral hemorrhage or nonhemorrhagic neurological deficits. The authors have defined this subgroup as symptomatic CVD. Patients who present incidentally or with symptoms of pulsatile tinnitus or ophthalmological phenomena have a less aggressive clinical course. The authors have defined this subgroup as asymptomatic CVD. Based on recent data the annual rate of intracerebral hemorrhage is 7.4-7.6% for patients with symptomatic CVD compared with 1.4-1.5% for those with asymptomatic CVD. The addition of asymptomatic CVD or symptomatic CVD as modifiers to the Borden-Shucart and Cognard systems improves their accuracy for risk stratification of patients with high-grade dural arteriovenous fistulas.