Management of PHACES syndrome: Risk of stroke and its prevention from a neurosurgical perspective

Abstract

Background and objectives: A multidisciplinary approach for PHACES is essential. A meticulous diagnostic and treatment protocol for PHACES patients with cerebrovascular anomalies within the intermediate and high risk strata for ischemic stroke is presented. We also differentiate the vasculopathy associated with PHACES syndrome from moyamoya angiopathy.

Methods: Medical records and radiological imaging were reviewed. After initial magnetic resonance imaging/angiography (MRI/MRA), H₂¹⁵O-PET scan (baseline and Acetazolamide challenge) was performed in three patients and 6-vessel cerebral angiography was performed in two patients. Two patients with significant intracranial cerebrovascular anomalies underwent cerebral revascularization.

Results: Each patient presented with a facial hemangioma at birth and additional cerebrovascular anomalies ranging from hypoplasia to steno-occlusive changes of intracranial cerebral arteries. Additional involvement of the cardiovascular system was observed in two patients. Additional to MRI/MRA, a H₂¹⁵O-PET helped stratify the three patients into intermediate (n=1) and high risk groups (n=2). The high-risk group patients underwent individualized cerebral revascularization for future stroke prevention. The patient in intermediate risk group will be followed. Cerebrovascular angiopathy seen in all patients was typical for PHACES without moyamoya and was not progressive at follow-up.

Conclusions: Patients within the intermediate and high-risk strata for ischemic stroke must undergo a 6-vessel cerebral angiography and further hemodynamic evaluation to indicate need for cerebral revascularization to prevent ischemic stroke. Non-progressive vasculopathy associated with PHACES can itself be hemodynamically relevant for neurosurgical intervention. This vasculopathy is distinct from moyamoya angiopathy, which can occur in conjunction with PHACES, resulting in concurrent progressive vasculopathy that would otherwise be absent.

Keywords: Angiopathy; Cerebral Revascularization; Moyamoya; PHACES; Stroke; Vasculopathy.