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应用单光子发射计算机断层(SPECT)结合放射性标记的同位素示踪剂,如IMP、99mTc-HMPAO与99mTc-ECD和133Xe,至今仍作为测定脑血流量(CBF)的金标准。正电子发射断层扫描(PET)可通过放射性同位素标记的氧、葡萄糖或其他化合物间接地测定CBF。动态的或功能的核磁共振成像通过去氧血红蛋白或氧敏感的成像技术评估CBF。CT成像技术与133Xe清除率联合应用测定CBF,从1978年至今,仍可视为另一种CBF测定的金标准,其敏感性与特异性均超过60％。TCD作为无创的脑血流速度检测技术,直到1990年以后才始用于脑血管反应性的检测。所有的上述检测技术或方法,在一些特异的脑血管舒张剂或方法应用之前,均不能准确测定脑血管功能储备(CRC)。只是当这些方法与特异性的脑血管舒张剂或方法,如应用乙酰唑胺、吸入二氧化碳或短时间屏气联合应用时,CRC的检测可成为可能。
Applications Single photon emission computed tomography (SPECT) combined with radiolabeled isotope tracers, such as IMP, 99mTc-HMPAO and 99mTc-ECD, and 133Xe are still the gold standard for determining cerebral blood flow (CBF). Positron emission tomography (PET) CBF can be measured indirectly by radioisotope-labeled oxygen, glucose, or other compounds. Dynamic or Functional Magnetic Resonance Imaging CBF is evaluated by deoxyhemoglobin or oxygen-sensitive imaging techniques. The combination of CT imaging and 133Xe clearance for the determination of CBF has remained the gold standard for another CBF assay from 1978 up to now, with a sensitivity and specificity of more than 60%. TCD as a non-invasive detection of cerebral blood flow velocity, until after the beginning of 1990 for the detection of cerebrovascular reactivity. All of the above detection techniques or methods can not accurately determine the cerebrovascular functional reserve (CRC) until some specific cerebral vasodilators or methods are used. Only when these methods and specific cerebral vasodilators or methods, such as the use of acetazolamide, inhaled carbon dioxide or short-term breath holding gas in combination, the detection of CRC may be possible.