Frequency and Clinical Course of Stroke and Transient Ischemic Attack Patients With Intracranial Nonocclusive Thrombus on Computed Tomographic Angiography

We sought to determine the frequency and clinical course of patients with acute ischemic stroke or transient ischemic attack (TIA) who had intracranial nonocclusive thrombus (iNOT) on CT angiography (CTA). We retrospectively (June 2002-March 2007) reviewed consecutive patients with acute ischemic stroke or TIA who had CTA performed acutely for diagnostic work-up. A neuroradiologist reviewed all cases with potential iNOT. Criteria to diagnose iNOT rather than occlusive thrombus or atherosclerotic stenosis were: (1) residual lumen present and eccentric; (2) nontapering thrombus; (3) smooth and well-defined thrombus margins; and (4) absence of vessel wall calcification. We defined functional independence at discharge as modified Rankin scale score