Low detection rate of craniocervical arterial dissection in children using time-of-flight magnetic resonance angiography: causes and strategies to improve diagnosis.

Craniocervical arterial dissection is a frequent cause of childhood arterial ischemic stroke requiring prompt diagnosis and treatment. However, there is no universal guideline for diagnostic cerebrovascular imaging in children. We assessed the role of time-of-flight magnetic resonance angiography in diagnosing craniocervical arterial dissection. We included children (1 month to 18 years) with craniocervical arterial dissection and ischemic stroke from January 1998 to June 2007. Institutional protocol required magnetic resonance imaging (MRI)/ magnetic resonance angiography for all ischemic stroke cases and conventional cerebral angiography if magnetic resonance angiography showed any arteriopathy. Among 233 ischemic stroke cases, craniocervical arterial dissection was diagnosed in 13 patients (5.6%; 10 males), with a mean age of 7.5 years. Initial time-of-flight magnetic resonance angiography missed dissection in 8 patients (61.5%) because the neck vessels were not scanned (n = 2), of suboptimal technique (n = 3), and of diagnostic error (n = 3). T1 fat-saturated MRI and contrast-enhanced magnetic resonance angiography were not performed in 12 patients. If suspicion for arterial dissection is high, T1 fat-saturated neck imaging and contrast-enhanced magnetic resonance angiography should be considered to maximize detection.