摘要

BACKGROUND: Due to collateral circulation and cerebrovascular reserve, arterial stenosis and reduced cerebral blood flow may not necessarily indicate impaired cerebral perfusion. Therefore, according to degree of stenosis and clinical symptoms, interventional surgery to relieve arterial stenosis in transient ischemic attack (TIA) patients with major intracranial stenosis is imprudent. Rather, cerebral perfusion and reserve capacity are direct indicators for the assessment of degree and presence of cerebral ischemia. OBJECTIVE: To evaluate cerebral perfusion and reserve in TIA patients with major intracranial stenosis or occlusion using magnetic resonance-perfusion-weighted imaging (MR-PWI) data prior to and following diamox administration. DESIGN, TIME AND SETTING: A self-comparative, neuroimaging observation was performed at the Neurological Department and Radiological Center of the First Affiliated Hospital of Jinan University between December 2007 and April 2009. PARTICIPANTS: Seven acute TIA patients, who were admitted to the Neurological Department of the First Affiliated Hospital of Jinan University between December 2007 and April 2009, were enrolled in the present study. Magnetic resonance imaging confirmed that no acute cerebral infarction happened, nor did bleeding exist. Magnetic resonance angiography, transcranial Doppler ultrasound, and/or digital subtraction angiography confirmed the presence of major intracranial arterial stenosis. Clinical symptoms corresponded to blood supplying regions of the arterial stenosis. METHODS: Baseline MR-PWI was performed on seven patients with intracranial stenosis or occlusion. Two grams of acetazolamide (diamox) were orally administered after 2 days. A second PWI was performed after 2 hours to compare cerebral perfusion parameters prior to and following diamox administration. MAIN OUTCOME MEASURES: PWI results of cerebral perfusion prior to and following diamox administration. RESULTS: The baseline PWI from five patients indicated decreased cerebral perfusion areas. Following oral administration of diamox, cerebral perfusion significantly decreased in those areas. Moreover, new areas of decreased cerebral perfusion were observed in two out of the five patients. In one patient, no significant decrease in cerebral perfusion was found. In another patient, baseline PWI indicated decreased cerebral perfusion in the left hemisphere. However, normal perfusion was observed in both cerebral lobes following diamox administration. CONCLUSION: TIA patients with intracranial stenosis, who are diagnosed by PWI and exhibited decreased cerebral perfusion and reserve, might require further treatment such as intervention by angioplasty.

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