Frey syndrome-like developmental dysautonomia in a child with PHACE syndrome.

PHACE syndrome classically presents with a large, segmental facial infantile hemangioma (IH) associated with structural and vascular abnormalities involving the head and neck, heart, and eyes. We evaluated an infant who presented with ptosis caused by a clinically subtle, deep right-sided periorbital IH identified on MRI that also incidentally revealed hypoplasia of the right common carotid and right internal carotid arteries, supporting a diagnosis of PHACE syndrome. She subsequently developed acute-onset, transient right-sided facial erythema without anisocoria, triggered by feeding and emotional stress. We believe this represents a Frey syndrome-like developmental dysautonomia, previously unreported in association with PHACE syndrome, suggesting an associated defect in neurovascular embryogenesis.