Yue Esther L, Meckler Garth D, Fleischman Ross J, Selden Nathan R, Bardo Dianna M E, Chu O'Connor Amity K, Vu Eugene T, Fu Rongwei, Spiro David M
Division of Pediatric Emergency Medicine.
J Neurosurg Pediatr. 2015 Apr;15(4):420-6. doi: 10.3171/2014.9.PEDS14207. Epub 2015 Jan 30.
Quick brain magnetic resonance imaging (QB-MRI) is a rapid, radiation-free technique to detect life-threatening CSF shunt malfunction. QB-MRI has not been widely studied or adopted. The primary objective of this study was to evaluate the test characteristics of QB-MRI for detecting shunt malfunction. Test characteristics of brain computed tomography (CT) and QB-MRI were then compared. Secondary objectives included comparison of time to study completion and use of sedatives for both modalities, as well as comparison of time to study completion for QB-MRI before and after implementation of a Pediatric Emergency Department (PED) shunt clinical pathway.
A retrospective chart review was performed at 2 tertiary care hospital PEDs. The authors reviewed the charts of children who underwent QB-MRI or CT for suspected shunt malfunction between July 2008 and June 2012. They also reviewed the patients' neuroradiology reports and classified ventricular size as positive (enlarged) or negative (normal, smaller, or unchanged). Shunt malfunction was defined by surgical revision within 30 days.
Nine hundred ninety-seven PED visits (involving 724 QB-MRIs and 273 CTs) were included. Surgical revision was performed in 235 cases (23.6%). For QB-MRI, sensitivity was 58.5% (95% CI 51.1%-65.6%) and specificity was 93.3% (90.8%-95.3%). For CT, sensitivity was 53.2% (95% CI 38.1%-67.9%) and specificity was 95.6% (92%-97.9%). The mean time to completion of QB-MRI was 115 minutes versus 83 minutes for CT (difference 32 minutes, 95% CI, 22-42 minutes, p < 0.001). The mean time from presentation to completion of QB-MRI prior to application of the CSF shunt pathway was 132 minutes versus 112 minutes after application of the CSF shunt pathway (difference 20 minutes, 95% CI 5-35 minutes, p = 0.01). Anxiolytic medications were used in 3.7% of CT studies and 4.4% of QB-MRI studies (p = 0.74).
QB-MRI and CT have similar test characteristics for detecting CSF shunt malfunction in children and similar requirements for sedation. The longer interval from order placement to imaging completion for QB-MRI is arguably justified by reduction of radiation exposure in this population subject to frequent brain imaging.
快速脑磁共振成像（QB-MRI）是一种快速、无辐射的技术，用于检测危及生命的脑脊液分流器故障。QB-MRI尚未得到广泛研究或应用。本研究的主要目的是评估QB-MRI检测分流器故障的测试特征。然后比较脑计算机断层扫描（CT）和QB-MRI的测试特征。次要目的包括比较两种检查方式完成检查所需时间以及镇静剂的使用情况，以及比较小儿急诊科（PED）分流临床路径实施前后QB-MRI的检查完成时间。
在两家三级医疗医院的小儿急诊科进行了一项回顾性图表审查。作者回顾了2008年7月至2012年6月期间因疑似分流器故障接受QB-MRI或CT检查的儿童图表。他们还审查了患者的神经放射学报告，并将脑室大小分类为阳性（扩大）或阴性（正常、较小或不变）。分流器故障定义为在30天内进行手术修复。
共纳入997次小儿急诊科就诊（涉及724次QB-MRI和273次CT）。235例（23.6%）进行了手术修复。对于QB-MRI，敏感性为58.5%（95%CI 51.1%-65.6%），特异性为93.3%（90.8%-95.3%）。对于CT，敏感性为53.2%（95%CI 38.1%-67.9%），特异性为95.6%（92%-97.9%）。QB-MRI的平均完成时间为115分钟，而CT为83分钟（差异32分钟，95%CI 22-42分钟，p<0.001）。在应用脑脊液分流路径之前，从就诊到QB-MRI完成的平均时间为132分钟，应用脑脊液分流路径之后为112分钟（差异20分钟，95%CI 5-35分钟，p=0.01）。3.7%的CT检查和4.4%的QB-MRI检查使用了抗焦虑药物（p=0.74）。
QB-MRI和CT在检测儿童脑脊液分流器故障方面具有相似的测试特征，并且在镇静要求方面相似。对于这个经常进行脑部成像的人群，QB-MRI从下单到成像完成的间隔时间较长，可以通过减少辐射暴露来证明是合理的。
