Pediatric Basilar Artery Occlusion and Vertebral Artery Dissection Successfully Treated with Thrombectomy and Flow Diversion: Asymptomatic Occlusion of the Cervical Flow Diverter Stent due to Mechanical Compression in Follow-Up

Pediatric ischemic stroke (PS) is a pathology with rare incidence and lower mortality than that of adult stroke, but high morbidity and potentially devastating outcomes, particularly for the posterior circulation. The most common reason for PS is cardiac disease. Although data are sparse, mechanical thrombectomy appears to be a safe treatment option in children when performed in a timely manner. Here, we present the case of a 13-year-old boy with an acute thromboembolic basilar artery bifurcation and left posterior cerebral artery occlusion, a stenosing dissection of the dominant left vertebral artery (VA) in the pre-atlas-loop section (V3), and an associated small dissecting aneurysm. The BA was successfully re-opened through aspiration thrombectomy, and the VA dissection and aneurysm were subsequently treated by implantation of a flow diverter stent (FDS) in the same session. The patient recovered well; however, in a routine follow-up digital subtraction angiography performed 4 months later, the FDS in the transverse foramen of the second vertebral body was wholly compressed, and the left VA was occluded. The posterior circulation appeared well supplied by the former hypoplastic right VA. This chapter describes the treatment of PS with a remarkable rare dissection of the left V3 segment. The FDS was positioned in a highly mobile segment of the left VA and the adjacent cervical spine; however, a bony anomaly might have been the main contributor to both the initial dissection and the subsequent stent compression. The right VA was initially hypoplastic. After the occlusion of the left VA, the right VA took over the supply of the posterior circulation, and showed enlarged vessel diameter.