Management algorithm in newly diagnosed European moyamoya angiopathy: One year experience at the Moyamoya Center, University Children's Hospital Zurich

Aims: Moyamoya angiopathy is a progressive steno-occlusive angiopathy of the circle of Willis. In the pediatric age group, clinical presentation is mainly cerebral ischemia. We present the management algorithm followed over a period of 1 year in newly diagnosed cases at the Moyamoya Center, University Children's Hospital Zurich. Methods: Fifteen newly diagnosed children over a period of 1 year underwent diagnostic and presurgical evaluation followed by tailor-made cerebral revascularization in 14 children. Results: The management algorithm consisted of the following: (A) Diagnostic/presurgical workup: (1) Clinical/neurological evaluation-Genetic phenotying/genotyping and cognitive/behavior testing were also performed. All patients except four presented with bilateral transient ischemic attacks. All patients except five had bilateral strokes. (2) Neuroradiological evaluation-MRI stroke protocol, H215O-PET (baseline and Diamox challenge), 6-vessel cerebral angiography. Bilateral angiopathy was seen in 13 children. Fourteen children showed decrease perfusion reserves after Diamox challenge either unilaterally or bilaterally in different cerebral arterial territories. (B) Correlation of findings and decision making: In light of clinical presentations, severity of angiopathy on angiography, that is, number of cerebral arterial territories involved and pattern of cerebral perfusion reserves on Diamox challenge, preoperative surgical plan was tailor made for every individual child. (C) Multiple cerebral revascularization procedures in one or two stages: Fourteen children underwent cerebral revascularization. Majority underwent two-staged procedures. The first stage consisted of revascularization of middle cerebral artery territory followed within a week by revascularization of anterior cerebral artery territory. Conclusion: Moyamoya angiopathy is not limited to the Asian population. Meticulous presurgical workup followed by neurosurgical treatment in the setting of a dedicated center with an infrastructure appropriate for the pediatric age group is pivotal for optimal outcome.