FOCAL CEREBRAL ISCHEMIA IN ACUTE BRAIN INJURY

每年约有200万人遭受创伤性脑损伤 在美国，这些人中约有10万人死亡，9万人死亡 长期残疾。在这些患者的管理方面取得了进展 降低了死亡率，但对改善脑损伤几乎没有什么作用。近期 对重型颅脑损伤患者的研究表明，局部减少 损伤后头几小时的脑血流量(RCBF)对 继发性脑损伤。为了确定大脑的作用 脑缺血在脑外伤的病理生理学中，重要的是要确定 颅脑损伤患者的rCBF减少是由于原发的减少。 导致缺血的供应或仅仅代表rCBF下降 继发于受损脑组织代谢需求的减少。正电子 发射断层扫描(PET)是目前唯一可用的技术 可以对人类的CBF和CMRO2进行区域性量化，并提供 CBF和CMRO2的平衡；氧提取分数OEF， 动静脉氧含量(A-VDO2)和脑静脉氧含量的差异 内容物(CvO2)。巴恩斯--华盛顿大学医学院犹太医院 中心是一家I级创伤中心，可容纳约120名1 每年都有病人。一种新的西门子ECAT精密HR 47PET扫描仪已经被 安装在神经科/神经外科重症监护病房(NNICU)，并 目前正被用于研究脑外伤患者。PET扫描仪的存在 在NNICU，结合我们在使用PET方面的丰富经验 为了检测脑缺血，我们在脑损伤临床治疗方面的专业知识 患者，而庞大的可用患者群体为我们提供了 解决这些问题的独特机会。我们建议调查 重型颅脑损伤患者脑缺血的患病率、严重程度和持续时间。 具体地说，我们将测量区域CBF。CMRO2、CvO2、A-VDO2和OEF 应用正电子发射计算机断层扫描治疗重型颅脑损伤60例 至8)在受伤后12小时内，24-72小时后再次。 这些研究对于优化这些疾病的治疗至关重要。 病人。如果脑缺血是颅脑损伤的一个重要问题，那么治疗 动脉高血压和脑灌注压将需要 相应地进行了修改。此外，神经保护剂目前正在 对缺血性卒中的研究可能对脑外伤也有帮助。

Each year approximately 2 million people suffer traumatic brain injuries (TBI) in the U.S. of these about 100,000 die and 90,000 are left with long-term disabilities. Advances in the management of these patients have reduced mortality but done little to ameliorate brain injury. Recent studies in severe TBI patients have suggested that reduced regional cerebral blood flow (rCBF) in the first few hours after injury contributes to secondary brain injury. in order to determine the role of cerebral ischemia in the pathophysiology of TBI, it is important to determine if the reduction in rCBF seen in TBI patients is due to a primary reduction in supply causing ischemia or merely represents a decline in rCBF secondary to reduced metabolic demands of injured brain tissue. Positron emission tomography (PET) is the only technology currently available that can quantify CBF and CMRO2 regionally in humans, and provide indices of the balance between CBF and CMRO2; oxygen extraction fraction OEF, differences in arteriovenous O2 content (A-VDO2), and cerebrovenous oxygen content (CvO2). Barnes-Jewish Hospital at Washington University Medical Center is a Level I trauma center which admits approximately 120 TB1 patients each year. A new Siemens ECAT EXACT HR 47 PET scanner has been installed in the Neurology/Neurosurgery Intensive Care Unit (NNICU) and is currently being used to study TBI patients. The presence of a PET scanner in the NNICU, combined with our extensive experience with the use of PET to detect ischemia, our expertise in the clinical management of TBI patients, and the large available patient patient population gives us a unique opportunity to address these issues. We propose to investigate the prevalence, severity, and duration of cerebral ischemia in severe TBI. Specifically we will measure regional CBF. CMRO2, CvO2, A-VDO2 and OEF using PET in 60 patients with severe head injury (GCS less then or equal to 8) within the first 12 hours after injury and again 24-72 hours latter. These investigations are critical to optimize treatment for these patients. If ischemia is a significant problem in TBI, then management of arterial hypertension and cerebral perfusion pressure will need to modified accordingly. In addition neuroprotective agents currently being studied in ischemic stroke may be useful in TBI as well.