Hofkes Shawn K, Iskandar Bermans J, Turski Patrick A, Gentry Lindell R, McCue Jeremy B, Haughton Victor M
Department of Radiology, University of Wisconsin School of Medicine and Public Health, Clinical Science Center-E3/311, Madison, WI 53792-3252, USA.
Radiology. 2007 Nov;245(2):532-40. doi: 10.1148/radiol.2452061096. Epub 2007 Sep 21.
To determine the sensitivity and specificity of cerebrospinal fluid (CSF) flow imaging in distinguishing between patients with symptomatic Chiari I malformation and those with asymptomatic tonsilar ectopia by using a neurosurgeon's overall clinical determination as the reference standard.
The institutional review board of the University of Wisconsin Hospital and Clinics approved our HIPAA-compliant retrospective study and granted a waiver for informed consent. Seventeen patients (five male, 12 female; aged 4-43 years) with tonsils extending more than 5 mm below the foramen magnum were classified by the neurosurgeon as symptomatic for Chiari I malformation or asymptomatic for tonsilar ectopia. The CSF flow images of the two groups were read independently in blinded fashion by four neuroradiologists. Reader agreement was calculated as percentage of readings in each patient that agreed with the neurosurgeon's classification. Sensitivity and specificity were respectively calculated as the percentage of abnormal readings in symptomatic patients and the percentage of normal readings in asymptomatic patients.
Of 17 patients, nine were classified by the neurosurgeon as symptomatic Chiari I malformation and eight as asymptomatic tonsilar ectopia. Agreement between pairs of readers was 63%-44%. For sagittal and transverse images, reader sensitivity for finding abnormal flow in symptomatic Chiari I malformation patients averaged 76% and specificity for normal flow in patients with asymptomatic tonsilar ectopia averaged 62%. The number of positive readings in the symptomatic patient group was significantly greater than that in the asymptomatic group (P < .02).
Readers detected an abnormal CSF flow pattern significantly more often in patients with symptomatic Chiari I malformation than in patients with asymptomatic tonsilar ectopia.
以神经外科医生的整体临床判断作为参考标准，确定脑脊液（CSF）流动成像在区分有症状的Chiari I畸形患者和无症状扁桃体异位患者中的敏感性和特异性。
威斯康星大学医院和诊所的机构审查委员会批准了我们符合HIPAA的回顾性研究，并豁免了知情同意书。17例扁桃体延伸至枕大孔以下超过5mm的患者（5例男性，12例女性；年龄4 - 43岁），经神经外科医生分类为有症状的Chiari I畸形或无症状的扁桃体异位。两组的脑脊液流动图像由四位神经放射科医生以盲法独立解读。读者间的一致性计算为每位患者与神经外科医生分类一致的解读百分比。敏感性和特异性分别计算为有症状患者中异常解读的百分比和无症状患者中正常解读的百分比。
17例患者中，9例被神经外科医生分类为有症状的Chiari I畸形，8例为无症状的扁桃体异位。读者间的一致性为63% - 44%。对于矢状位和横断位图像，有症状的Chiari I畸形患者中发现异常血流的读者敏感性平均为76%，无症状扁桃体异位患者中正常血流的读者特异性平均为62%。有症状患者组的阳性解读数量显著多于无症状组（P < 0.02）。
与无症状扁桃体异位患者相比，读者在有症状的Chiari I畸形患者中检测到异常脑脊液流动模式的频率明显更高。
