Kevin O’Connor, MD
Focal cerebral arteriopathy (FCA) is the cause of up to a quarter of strokes in children. FCA involves a focal and unilateral stenosis or irregularity of the distal internal carotid artery and its proximal branches. The suspected underlying pathophysiology is arterial inflammation resulting in vessel narrowing and thrombus formation on damaged endothelium. Post-varicella FCA is a common etiology and may occur within a year of infection. Imaging mimics of FCA include dissection, moyamoya, and embolus. Children with FCA may have progression of symptoms over several days/weeks, and up to a quarter have another stroke within a year.
Oesch et al. identified 15 cases (8%) of FCA among 179 children with strokes at a single center between 2009-2019. The median age was 6.8 years (range 0.5-16.3 years) and 8 were boys. Common presenting symptoms included hemiparesis (n=14), headache (n=7), and a concomitant infectious process (n=6). Two of thirteen tested children (15%) were positive for VZV antibodies and VZV DNA. The lower incidence of FCA with recent VZV infection compared to prior studies may be related to increased VZV vaccination. Six children had stuttering symptoms over 1-4 days prior to stroke. Three children (20%) had progression of stroke symptoms after the initial event. All 15 children received antithrombotic therapy following the stroke and over the course of follow-up (at least one year in 14 of 15 children). Data on the safety and efficacy of steroid use in FCA is unclear.
The most commonly involved arterial segments at presentation were the M1 (n=14, 93%), A1 (n=12, 80%), distal ICA (n=11, 73%), and M2 (n=7, 47%). The median FCA Severity Score (FCASS) on presentation was 3 (Q1-Q3, 2-3), indicating most children had a >50% stenosis. Eight children had occluded segments at presentation (FCASS 4) with four demonstrating subsequent recanalization. The most common residual deficits were sensorimotor, likely secondary to involvement of the M1 segment in most children.
FCA is an important diagnostic and clinical consideration when evaluating stroke in children, but additional studies are needed to better understand its pathophysiology, vascular imaging characteristics to differentiate it from its mimics, and optimal treatment strategies.