Alejandro Fuerte, MD
Craniocervical arterial dissection (CCAD) is a crucial emergency state causing 7.5% to 20% of all childhood arterial ischemic stroke (AIS) cases, with an annual incidence of all AIS estimated at 2.5 to 8 per 100,000 children per year. Childhood CCAD cases are often spontaneous or in association with head and neck trauma, both blunt injuries and hyperextension or manipulation of the neck. With spontaneous CCAD, at least 5% to 20% of children have an underlying risk factor, such as connective tissue diseases, genetic disorders, anatomic vascular variations or familial segregation. The clinical presentation of CCAD is non-differentiating from other causes of AIS aside from a history of head and neck trauma or pain. Magnetic resonance imaging is the preferred neuroimaging method, followed by cerebral catheter angiography as a gold standard definitive neurovascular imaging modality when initial vascular imaging reveals non-diagnostic findings.
For this review, the authors searched MEDLINE (2000 to 2018) for articles that contained patients aged less than 18 years with craniocervical arterial dissection, with the aim of analyzing their characteristics. Sixteen articles met the study criteria and reported 182 cases of craniocervical arterial dissection. 68% were male individuals, with an average of 8.6 years of age. From the 182 cases reviewed, 102 (56%) cases experienced concurrent or preceding trauma as the risk factor for dissection; 25% of these were associated with some type of contact sport or physical activity, and skull or spine fracture(s) was listed as a risk factor in 14%. Several risk factors were identified among the spontaneous dissection cases (mainly aberrant vertebral arcuate foramina).
Types of craniocervical arterial dissection CCAD can be categorized based on the location of dissection (extracranial versus intracranial) and circulation involved (anterior versus posterior circulation). Extracranial dissection (ECD) is common in children (55% to 75% of CCAD cases), and posterior circulation (mainly the vertebral artery) is more frequently affected. Intracranial dissection (ICD) is noted in up to 25% of CCAD cases, and anterior circulation (mainly internal carotid artery) is more commonly affected.
Since there is no characteristic form of presentation, CCAD in children is difficult to distinguish from stroke caused by other etiologies. The review showed hemiparesis (49%) and headache (39%) as the two most common presenting features. Neck pain is usually uncommon, unlike in adult cases.
The diagnosis of CCAD is based on clinical suspicion and the demonstration of specific neurovascular imaging findings. Suggestive symptoms of a posterior circulation AIS, recent trauma, or a personal history of comorbid diagnoses, such as connective tissue disease, increase suspicion of CCAD.
According to the international pediatric stroke study, confirmation diagnosis of CCAD requires angiographic findings of a double lumen (uncommon in children), intimal flap (20% of CCAD cases), or pseudoaneurysm (7.6% to 33% of childhood CCAD cases), or on axial T1 fat-saturated MRI demonstration of intramural hematoma visualized as a “bright crescent sign” in the arterial wall (commonly reported in adults, not as frequently in children; 6% to 40% of pediatric CCAD cases). Other arterial abnormalities indicative of stenosis or occlusion are common findings in both adult and pediatric cases of CCAD; however, these arterial abnormalities are only considered diagnostic of dissection when coupled with a preceding history of head and neck trauma or neck pain, or when located at the level of C2 vertebral body.
Close clinical and neurovascular imaging follow-up of children with CCAD is important due to high AIS recurrence rates (12-19%). Therefore, follow-up neurovascular imaging is recommended to be performed within 3 to 6 months after the initial presentation, as recommended in adult cases, specifically when initial vascular imaging revealed nondiagnostic results.
At the end of the article, the authors review treatment options. According to the American Heart Association (AHA) and American Stroke Association (ASA) guidelines for management of stroke in children (2008), anticoagulant treatment is reasonable in children with ECD for a period of three to six months (class IIa, evidence level C) and treatment with anticoagulation is not recommended in children with ICD (class III, evidence level C). However, this recommendation requires further discussion due to the results obtained in the Carotid Artery Dissection in Stroke study (in adults): no difference in the efficacy of either antiplatelet or anticoagulant drugs; slight increase in hemorrhages in the group treated with anticoagulant. Lastly, add that according to a recent statement from ASA/AHA (Stroke. 2019), in cases of dissection and hypermobility on examination, clinicians should consider appropriate genetic screening for connective tissue disorders.