From the Department of Neurosurgery (K.F., S.O., S.T., W.Y., S.F., M.K., Y.K., K.Y., K.O.).
Division of Ultrahigh Field MRI, Institute for Biomedical Sciences (I.U., M.S.).
AJNR Am J Neuroradiol. 2020 May;41(5):785-791. doi: 10.3174/ajnr.A6508. Epub 2020 Apr 16.
Dynamic changes in cerebrovascular reactivity after acetazolamide administration vary markedly among patients with major cerebral arterial steno-occlusive disease. MR quantitative susceptibility mapping can dynamically quantify the cerebral magnetic susceptibility. The purpose of this study was to determine whether dynamic changes in susceptibility after administration of acetazolamide on 7T quantitative susceptibility mapping are associated with pre-existing states of CBV and the cerebral metabolic rate of oxygen in the cerebral hemispheres with major cerebral arterial steno-occlusive disease.
Sixty-five patients underwent 7T MR imaging at baseline and at 5, 10, 15, and 20 minutes after acetazolamide administration. Differences between the susceptibility of venous structures and surrounding brain tissue were calculated in the quantitative susceptibility mapping images. Susceptibility differences at 5, 10, 15, and 20 minutes after acetazolamide administration relative to baseline were calculated in 97 cerebral hemispheres with major cerebral arterial steno-occlusive disease. CBV and the cerebral metabolic rate of oxygen were also calculated using O-gas PET in the resting state.
Dynamic changes of susceptibility after acetazolamide administration were classified into 3 patterns: abnormally increasing 5 or 10 minutes after acetazolamide administration; abnormally decreasing within 20 minutes after acetazolamide administration; and remaining unchanged after acetazolamide administration. CBV was significantly greater in the first pattern than in the latter 2. The cerebral metabolic rate of oxygen differed significantly in descending order from the first to middle to last pattern.
Dynamic changes of susceptibility after acetazolamide administration on 7T MR quantitative susceptibility mapping are associated with pre-existing states of CBV and the cerebral metabolic rate of oxygen in major cerebral arterial steno-occlusive disease.
乙酰唑胺给药后脑血管反应性的动态变化在大血管狭窄性脑血管病患者中差异显著。MR 定量磁敏感图可动态定量脑磁化率。本研究旨在确定 7T 定量磁敏感图上乙酰唑胺给药后磁敏感的动态变化是否与大血管狭窄性脑血管病半球预先存在的 CBV 和脑氧代谢率状态相关。
65 例患者在基线和乙酰唑胺给药后 5、10、15 和 20 分钟进行 7T MR 成像。在定量磁敏感图图像中计算静脉结构和周围脑组织的磁化率差异。在 97 个大血管狭窄性脑血管病半球中，计算乙酰唑胺给药后 5、10、15 和 20 分钟相对于基线的磁化率差异。在静息状态下，使用 O-气体 PET 计算 CBV 和脑氧代谢率。
乙酰唑胺给药后磁化率的动态变化分为 3 种类型：乙酰唑胺给药后 5 或 10 分钟异常增加；乙酰唑胺给药后 20 分钟内异常减少；乙酰唑胺给药后保持不变。在第一种类型中，CBV 明显大于后两种类型。脑氧代谢率从第一种类型到中间到最后一种类型依次显著降低。
7T MR 定量磁敏感图上乙酰唑胺给药后磁化率的动态变化与大血管狭窄性脑血管病中预先存在的 CBV 和脑氧代谢率状态相关。
