RELATION BETWEEN CEREBRAL BLOOD-FLOW AND NEUROLOGIC DEFICIT RESOLUTION IN ACUTE ISCHEMIC STROKE

Background and objective: Early intervention remains the key to acute ischemic stroke therapy. Many patients whose deficits would later reso lve without intervention are exposed to the risks of stroke treatment without benefit. The purpose of this study was to determine whether pa tients with transient deficits could be distinguished from patients wi th evolving strokes on the basis of acute cerebral blood flow (CBF) me asurements before any clinical distinction could be made. Methods: Fif ty-three patients who presented with acute hemispheric stroke symptoms and who underwent xenon-enhanced CT (XeCT) CBF studies within 8 hours of onset of symptoms (and before any clinical improvement) were studi ed. Results: Eight patients (15%) had a complete resolution of their s ymptoms within 24 hours (not related to treatment). All eight patients with deficits that resolved had normal CBF in the symptomatic vascula r territories (mean time to XeCT = 3 hours, 51 min). Mean CBF in the r egions of interest of the symptomatic vascular territories of patients who had deficits that resolved was 35.4 +/- 8.1 mL.100.g(-1).min(-1) compared with 17.3 +/- 9.3 mL.100.g(-1).min(-1) of patients with evolv ing strokes (p = 0.00058). Conclusions: Patients with ischemic neurolo gic deficits that will later resolve can be acutely distinguished from patients with evolving cortical infarctions using XeCT CBF measuremen ts. CBF measurements may assist in the triage of patients for acute st roke therapy by selecting patients with a favorable prognosis and may not benefit from therapy but would still be exposed to the potential r isks and expense of treatment.