Yata Kenichiro, Suzuki Akifumi, Hatazawa Jun, Shimosegawa Eku, Nagata Ken, Sato Mika, Moroi Junta
Department of Strokology, Research Institute for Brain and Blood Vessels, Akita, Japan.
Stroke. 2006 Feb;37(2):534-6. doi: 10.1161/01.STR.0000199085.40000.cf. Epub 2006 Jan 12.
The present study examined the relationship between circulatory and metabolic reserve in patients with hemodynamic impairment.
Positron emission tomography was used to investigate 40 patients with major cerebral artery occlusive disease. The ratio of cerebral blood volume to cerebral blood flow (CBV/CBF) and vasoreactivity in response to hypercapnia (%CBF(hypercapnia)) and acetazolamide (ACZ) stress (%CBF(ACZ)) were measured to evaluate circulatory reserve. Oxygen extraction fraction (OEF) was measured to evaluate metabolic reserve. To detect relationships between circulation reserve and OEF, cerebral hemispheres were grouped into 5 or 6 stepwise groups based on reduction of circulation reserve.
OEF was significantly elevated in hemispheres with CBV/CBF > or =0.11 minutes and in hemispheres with %CBF(hypercapnia) <0%. OEF was significantly increased according to %CBF(ACZ) in hemispheres with %CBF(ACZ) <15% and plateaued at levels below -15%.
Metabolic reserve consumption began at CBV/CBF > or =0.11 minutes, CBF(hypercapnia) <0%, and CBF(ACZ) <15%.
本研究探讨了血流动力学受损患者循环储备与代谢储备之间的关系。
采用正电子发射断层扫描技术对40例大脑主要动脉闭塞性疾病患者进行研究。测量脑血容量与脑血流量之比（CBV/CBF）以及对高碳酸血症（%CBF(高碳酸血症)）和乙酰唑胺（ACZ）应激（%CBF(ACZ)）的血管反应性，以评估循环储备。测量氧摄取分数（OEF）以评估代谢储备。为检测循环储备与OEF之间的关系，根据循环储备的降低情况将大脑半球分为5或6个逐步分组。
在CBV/CBF≥0.11分钟的半球以及%CBF(高碳酸血症)<0%的半球中，OEF显著升高。在%CBF(ACZ)<15%的半球中，OEF根据%CBF(ACZ)显著增加，并在低于-15%的水平达到平稳状态。
代谢储备消耗始于CBV/CBF≥0.11分钟、CBF(高碳酸血症)<0%以及CBF(ACZ)<15%时。
