Frigon Chantal, Jardine David S, Weinberger Ed, Heckbert Susan R, Shaw Dennis W W
Department of Anesthesiology, Box 359300, University of Washington, Seattle, WA 98195, USA.
AJR Am J Roentgenol. 2002 Sep;179(3):791-6. doi: 10.2214/ajr.179.3.1790791.
Cerebrospinal fluid (CSF) hyperintensity has been described on fluid-attenuated inversion recovery (FLAIR) imaging in anesthetized patients who underwent MR imaging without apparent subarachnoid abnormality. The purpose of our study was to delineate likely causes for this hyperintensity. Specifically, we sought to determine whether a high inspired oxygen fraction given as part of the anesthetic was responsible for the CSF hyperintensity seen on FLAIR imaging.
A retrospective study was conducted using anesthetic records and brain MR images of 70 children and young adults who had a FLAIR sequence while undergoing general anesthesia. Information about inspired oxygen fraction, oxygen saturation, and type of anesthetic agents preceding the FLAIR sequence was obtained from the anesthetic record. A pediatric neuroradiologist who was unaware of the inspired oxygen fraction and anesthetic agent ascertained the presence of CSF hyperintensity in the basilar cisterns and cerebral sulcal subarachnoid space.
Twenty-one patients received an inspired oxygen fraction less than or equal to 0.60, and 49 received an inspired oxygen fraction greater than 0.60. Inspired oxygen fraction greater than 0.60 was significantly associated with the presence of CSF hyperintensity in the basilar cisterns (p < 0.001) and in the cerebral sulcal subarachnoid space (p = 0.03). The type of anesthetic agent, patient's sex, or status (based on the American Society of Anesthesiology physical status and classification system), and presence of cardiopulmonary disease or seizure disorder were not associated with CSF hyperintensity.
High inspired oxygen fraction during anesthesia is associated with CSF hyperintensity in the basilar cisterns and the cerebral sulcal subarachnoid space on FLAIR imaging in children and young adults. Physicians should be aware of this finding to avoid misinterpreting this artifact as an abnormality.
在接受磁共振成像（MR成像）且无明显蛛网膜下腔异常的麻醉患者中，液体衰减反转恢复（FLAIR）成像上已观察到脑脊液（CSF）高信号。本研究的目的是明确这种高信号的可能原因。具体而言，我们试图确定作为麻醉一部分给予的高吸入氧分数是否是FLAIR成像上所见CSF高信号的原因。
对70例儿童和青年成人进行回顾性研究，这些患者在全身麻醉期间进行了FLAIR序列成像。从麻醉记录中获取FLAIR序列之前的吸入氧分数、血氧饱和度和麻醉剂类型等信息。一位不了解吸入氧分数和麻醉剂的儿科神经放射科医生确定基底池和脑沟蛛网膜下腔中CSF高信号的存在情况。
21例患者的吸入氧分数小于或等于0.60，49例患者的吸入氧分数大于0.60。吸入氧分数大于0.60与基底池中CSF高信号的存在显著相关（p < 0.001），在脑沟蛛网膜下腔中也显著相关（p = 0.03）。麻醉剂类型、患者性别或状态（基于美国麻醉医师协会身体状况和分类系统）以及心肺疾病或癫痫疾病的存在与CSF高信号无关。
麻醉期间高吸入氧分数与儿童和青年成人FLAIR成像上基底池和脑沟蛛网膜下腔中的CSF高信号相关。医生应知晓这一发现，以避免将这种伪影误判为异常。
