Division of Neurosurgery, Department of Surgery, Chang Gung Memorial Hospital, Chang Gung University, Kweishan, Taiwan.
J Ultrasound Med. 2009 Nov;28(11):1487-92. doi: 10.7863/jum.2009.28.11.1487.
The purpose of this study was to evaluate hemispheric asymmetry of cerebral blood flow changes during various mental tests by applying transcranial Doppler sonography (TCD) to simultaneously monitor bilateral cerebral blood flow velocity changes.
Twenty-one participants without cerebrovascular disease performed 3 left hemispheric tasks (reading, calculation, and color scaling) and 3 right hemispheric tasks (face recognition, space imagination, and line orientation).
Mean velocities of the rest and performing periods did not differ significantly between the left and right hemispheric tasks. Although greater acceleration of blood flow velocity was observed on the left than on the right in most of the 6 tasks except line orientation (mean left - right ratio difference [D(l-r)] ranged from -0.018 to 0.071), this difference was larger for left hemispheric tasks (mean D(l-r) ranged from 0.050 to 0.071) than right hemispheric tasks (mean D(l-r) ranged from -0.018 to 0.034; P < .001). Further comparisons of each pair of (ie, left and right) hemispheric tasks revealed that the most suitable left and right hemispheric tasks to show hemispheric asymmetry were reading and line orientation, respectively (P < .001).
Hemispheric asymmetry of cerebral blood flow changes during mental tests is demonstrable with TCD only when comparing the D(l-r) in response to suitable paired left and right hemispheric tasks.
本研究旨在通过经颅多普勒超声（TCD）同时监测双侧脑血流速度变化，评估各种心理测试时大脑血流变化的半球不对称性。
21 名无脑血管疾病的参与者完成了 3 项左半球任务（阅读、计算和颜色分级）和 3 项右半球任务（人脸识别、空间想象和线条定向）。
休息期和执行期的平均血流速度在左、右半球任务之间无显著差异。尽管在大多数 6 项任务中（除线条定向外），左半球的血流速度加速均大于右半球（左-右比值差异的平均值 D(l-r)范围为 -0.018 至 0.071），但左半球任务的差异更大（D(l-r)平均值范围为 0.050 至 0.071），而右半球任务的差异较小（D(l-r)平均值范围为 -0.018 至 0.034；P <.001）。进一步比较每对（即左、右）半球任务，发现最适合显示半球不对称性的左、右半球任务分别是阅读和线条定向（P <.001）。
仅当比较合适的左、右半球配对任务的 D(l-r)时，TCD 才能显示出心理测试时大脑血流变化的半球不对称性。
