The acute diagnosis of Takayasu's arteritis based on helical CT angiography of the chest and neck in the emergency room

Recently, a young woman presented acutely with a left hemispheric stroke an d differing blood pressures in the arms as her initial manifestation of Tak ayasu's arteritis, Helical CT angiography, performed to rule out aortic dis section, revealed a thickened wall of the aortic arch with stenoses and occ lusions of the great vessels, suggesting the diagnosis. The sequence of ima ging studies and findings in this unusually catastrophic presentation of a typically insidious disease are highlighted.