Presentation of Dural Arteriovenous Fistulas in Children

Symptoms and Signs

Clinical presentation varies according to the age of presentation and location of the DAVF (24). In general, symptoms are caused by venous hypertension, hemorrhage, and mass effect due to variceal growth.

Neonatal Presentation

Patients who present as neonates have a poor prognosis and should be evaluated and treated promptly (18). The differential diagnosis for this group should include VOGM, which is otherwise a different pathology with different embryological origins and treatment strategies.

• Heart failure: In cases with very high cardiac output, the kidneys and liver might be affected.
• Cyanosis: Blue coloration of the skin, especially on the lips, and mucosa can be seen.
• Cranial bruits and facial vein prominence: Alternative routes of venous drainage through cavernous sinus and facial veins may be seen. These symptoms might be exacerbated with Valsalva maneuvers (ie, crying in neonates).

Infant Presentation

• Hydrocephalus: Increased venous pressure can impair CSF absorption and cause nonobstructive hydrocephalus. Large venous varices might also obstruct CSF pathways.
• Macrocephaly: Progressive increase of the head circumference may cross normative curves.
• Hemorrhage: Hemorrhage could be intracerebral or subarachnoid.
• Neurological sequalae: Patients who present as infants tend to do better than neonates but might have neurological sequelae months to years after diagnosis.

Childhood Presentation

• Headaches: Headache tends to be one of the most common symptoms. Older children may localize the headache, but these symptoms might only manifest as irritability in younger children.
• Focal neurological deficits: Deficits could be secondary to steal syndrome or venous congestion attributed to a high-flow fistula.
• Seizures: Any type of seizure can occur but, in general, they tend to be generalized seizures.
• Tonsillar herniation: Patients can present with Chiari-like symptoms (eg, neck pain, balance issues/dizziness, vision changes), generally due to venous hypertension.
• Cavernous sinus fistulas: Fistulas located at the cavernous sinus can produce proptosis, orbital bruit, visual failure, and chemosis.
• Syncope: Although rare, children might present with sudden syncope.

Patterns of Evolution

• Poorly understood natural history: The natural history of DAVF in children is poorly understood. Data are heterogeneous and mostly derived from retrospective studies in adults (25). Symptoms evolve depending on the preservation of normal venous drainage on the affected segment. If this is still present, symptoms might be absent or mild.
• Higher risk if symptomatic: Symptomatic cranial DAVFs tend to have a worse clinical progression than incidentally identified DAVFs (28). Mortality rates of 27% and 31% have been reported in larger case series (18,20).

Time for Evolution

• Annual hemorrhage rates vary by type: When stratified using the Djindjian classification system — which is essentially the Cognard system but does not include Cognard type V DAVFs — annualized nonhemorrhagic neurological deficit and hemorrhage rates are estimated to be 0.0% and 0.0% for type I, 4.5% and 3.4% for type II, 6.0% and 4.0% for type III, and 4.5% and 9.1% for type IV DAVFs in adults (26). One large pooled study that used the Borden classification system found that annual hemorrhage rates for type I, II, and III DAVFs were 0%, 6%, and 10%, respectively; the annual hemorrhage rate for type III DAVFs with venous ectasia was 21% (27).

Evaluation at Presentation

• Full neurological and cardiovascular history and physical examination: A full neurological and cardiovascular examination and collateral history is required.

Intervention at Presentation

Stabilization

• Patients who present with cardiac failure: These patients may require diuretics, inotropic agents (dopamine, dobutamine and digitalis), and vasodilators. Maintenance of adequate hydration is also important, as dehydration might promote an already existing venous thrombosis.
• Patients with hemorrhagic presentation: Especially in younger patients, ensure red cell packs are available, as well as fresh frozen plasma and prothrombin complex to prevent hemodilution.
• Patients with hydrocephalus and high ICP: Placement of an external ventricular drain is indicated in the acute setting. Large hematomas might require a craniotomy for evacuation.

Preparation for Definitive Intervention, Nonemergent

• Hydration: Because the mainstay treatment is now endovascular (which carries a risk of thrombosis), children must be adequately hydrated before going to the angiography suite.
• Blood products: If the recommended treatment is open surgery, ensure blood products are available.

Preparation for Definitive Intervention, Emergent

• Patient stabilization: The patient should be stabilized before an endovascular procedure or surgery is performed.

Admission orders

• Standard management for hemorrhage if indicated: If the child presents with ICH, basic neurosurgical principles must be followed, paying special attention to keep mean arterial pressures within their age range limits to maintain cerebral blood flow. Adequate hydration is of utmost importance, particularly in infants.
• Antiepileptics for seizure: Administer antiepileptic drugs in the event of seizures.
• Cardiac consultation if heart failure: In newborns with heart failure, consult the pediatric cardiology team. Fluid overload can be dangerous for these patients.
• Preparation for contrast agent administration: Preparation for noninvasive imaging tests and angiography should be arranged, including orders for fasting, a basic set of labs with coagulation studies, and adequate hydration.
• Preparation for surgery: Blood should be typed and crossmatched.