Ueno M, Nishizawa S, Toyoda H, Shimono T, Miyamoto S, Hashimoto N, Konishi J
Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Kyoto University, Japan.
Ann Nucl Med. 2001 Jun;15(3):209-15. doi: 10.1007/BF02987833.
The purpose of this study was to validate a double-injection (DI) method with N-isopropyl-[123I]p-iodoamphetamine (IMP) to measure regional cerebral blood flow (rCBF) twice in a single session of dynamic SPECT and to elucidate a possible role of this method to identify patients with occlusive disease of major cerebral arteries, who might benefit from cerebral revascularization procedures (CR).
Fourteen patients with occlusion or severe stenosis of the internal carotid or middle cerebral artery were studied before and after CR to assess hemodynamic changes after revascularization treatment. We quantitatively measured rCBF before and after acetazolamide (ACZ) challenge along with cerebrovascular reserve capacity (CVR) with two injections of IMP in a single session of dynamic SPECT scans (DI method). The reliability and reproducibility of the DI method were validated by means of a simulation study and in eight patients who were examined without ACZ challenge to measure baseline rCBF twice.
The analysis of simulated noisy data with realistic noise levels showed that the errors of the estimates for the first and the second rCBF and for the increase in rCBF were 2.6%, 8.1% and 10.4%, respectively. In the 8 patients examined by the DI method to measure baseline rCBF twice, the mean and the SD of percentage differences between the two consecutive measurements in rCBF were -1.3% and 5.5%, respectively. Eight out of 14 patients with occlusive disease had at least one region with a CVR less than 10%. They showed a significant increase in resting rCBF after CR, not only in the ipsilateral hemisphere (from 26.1 +/- 6.4 to 33.4 +/- 4.7) but also in the contralateral one (from 28.3 +/- 7.0 to 34.7 +/- 4.7) with a recovery of the ipsilateral CVR from 9.3 +/- 17.2 to 41.2 +/- 20.1%. The remaining six patients with good-moderate CVR did not show an increase in rCBF after CR (from 28.0 +/- 2.7 to 28.3 +/- 3.4). The three of them with a moderate CVR (10-25%) before CR showed normalization of CVR after CR.
Patients with decreased rCBF and reduced CVR benefited from CR in terms of an increase in rCBF and recovery of CVR. The quantitative double-injection IMP-SPECT has the ability to identify those patients who may benefit from CR.
本研究的目的是验证一种使用 N-异丙基-[123I]对碘安非他明（IMP）的双注射（DI）方法，以便在单次动态 SPECT 检查中两次测量局部脑血流量（rCBF），并阐明该方法在识别可能从脑血运重建手术（CR）中获益的大脑主要动脉闭塞性疾病患者方面的潜在作用。
对 14 例颈内动脉或大脑中动脉闭塞或严重狭窄的患者在 CR 治疗前后进行研究，以评估血运重建治疗后的血流动力学变化。在单次动态 SPECT 扫描（DI 方法）中，通过两次注射 IMP，我们在乙酰唑胺（ACZ）激发前后定量测量 rCBF 以及脑血管储备能力（CVR）。DI 方法的可靠性和可重复性通过模拟研究以及在 8 例未进行 ACZ 激发以两次测量基线 rCBF 的患者中得到验证。
对具有实际噪声水平的模拟噪声数据的分析表明，第一次和第二次 rCBF 估计值以及 rCBF 增加量的误差分别为 2.6%、8.1%和 10.4%。在通过 DI 方法两次测量基线 rCBF 的 8 例患者中，rCBF 两次连续测量之间百分比差异的平均值和标准差分别为 -1.3%和 5.5%。14 例闭塞性疾病患者中有 8 例至少有一个区域的 CVR 小于 10%。他们在 CR 后静息 rCBF 显著增加，不仅在同侧半球（从 26.1±6.4 增加到 33.4±4.7），而且在对侧半球（从 28.3±7.0 增加到 34.7±4.7），同侧 CVR 从 9.3±17.2 恢复到 41.2±20.1%。其余 6 例 CVR 良好至中等的患者在 CR 后 rCBF 未增加（从 28.0±2.7 增加到 28.3±3.4）。其中 3 例 CR 前 CVR 中等（10 - 25%）的患者在 CR 后 CVR 恢复正常。
rCBF 降低和 CVR 降低的患者在 rCBF 增加和 CVR 恢复方面从 CR 中获益。定量双注射 IMP - SPECT 有能力识别那些可能从 CR 中获益的患者。
