Segawa H, Yoshimasu N, Nakamura O, Aritake K, Wakai S, Takakura K, Kimura K, Ueda Y, Tamura A, Sano K
No To Shinkei. 1982 Mar;34(3):291-7.
The present study was conducted to overcome some of disadvantages of cerebral blood flow study by radionuclide, such as poor regionality of flow values and errors involved in pathological brains. Serial CT scanning was carried out during and after inhalation of 50 to 70% non-radioactive xenon in humans. Diffusible gas with high atomic number enhanced gray matter first 19 +/- 4 HU (mean +/- SD) on an average in Hounsfield unit (HU) and later white matter 24 +/- 4 HU. In seven normal subjects, blood flow in gray matter was 82 +/- 11 and that in white matter 24 +/- 5 ml/100 gm/min. Partition coefficient which is not readily obtainable by radionuclide study was 0.9 +/- 0.1 in normal gray matter and 1.4 +/- 0.2 in normal white matter. Two cases were presented to show k-map (clearance rate), lambda-map (partition coefficient) and CBF map, which displayed images of values calculated automatically, in black and white or color on CRT. The first case was a patient with metastatic brain tumor from lung in the left parietal region. The blood flow of the tumor was close to that of gray matter, whereas blood flow of edematous white matter surrounding the tumor was decreased to below 10 ml/100 g/min with partition coefficient ranged from 0 to 0.9. The second case was presented to demonstrate the resolution of the blood flow map obtained by this method. Multiple lacunar infarcts of the basal ganglia and white matter in the size of 1 to 3 mm, which were hardly identified on regular CT picture, were well visualized on CBF map. This method appeared to have several advantages over conventional isotope method and to provide useful clinical and research informations.
本研究旨在克服放射性核素脑血流研究的一些缺点，如血流值的区域特异性差以及病理脑所涉及的误差。在人体吸入50%至70%的非放射性氙气期间及之后进行了连续CT扫描。高原子序数的可扩散气体首先使灰质平均增强19±4亨氏单位（HU）（平均值±标准差），随后使白质增强24±4 HU。在7名正常受试者中，灰质血流为82±11，白质血流为24±5 ml/100克/分钟。放射性核素研究不易获得的分配系数在正常灰质中为0.9±0.1，在正常白质中为1.4±0.2。展示了两个病例的k图（清除率）、λ图（分配系数）和脑血流图，这些图在阴极射线管上以黑白或彩色显示自动计算出的值的图像。第一个病例是一名左顶叶区域有肺转移性脑肿瘤的患者。肿瘤的血流接近灰质血流，而肿瘤周围水肿白质的血流降至10 ml/100克/分钟以下，分配系数范围为0至0.9。第二个病例用于展示通过该方法获得的血流图的分辨率。基底节和白质大小为1至3毫米的多发性腔隙性梗死在常规CT图像上难以识别，但在脑血流图上清晰可见。该方法似乎比传统同位素方法有几个优点，并能提供有用的临床和研究信息。
