Alperin Noam, Loftus James R, Oliu Carlos J, Bagci Ahmet M, Lee Sang H, Ertl-Wagner Birgit, Green Barth, Sekula Raymond
*Department of Radiology, University of Miami, Miami, Florida; ‡Department of Radiology, University of Munich, Munich, Germany; §Department of Neurological Surgery, University of Miami, Miami, Florida; and ¶Neurological Surgery, University of Pittsburgh, Pennsylvania.
Neurosurgery. 2014 Nov;75(5):515-22; discussion 522. doi: 10.1227/NEU.0000000000000507.
It has been well documented that, along with tonsillar herniation, Chiari Malformation Type I (CMI) is associated with smaller posterior cranial fossa (PCF) and altered cerebrospinal fluid (CSF) flow and tissue motion in the craniocervical junction.
This study assesses the relationship between PCF volumetry and CSF and tissue dynamics toward a combined imaging-based morphological-physiological characterization of CMI. Multivariate analysis is used to identify the subset of parameters that best discriminates CMI from a healthy cohort.
Eleven length and volumetric measures of PCF, including crowdedness and 4th ventricle volume, 4 measures of CSF and cord motion in the craniocervical junction, and 5 global intracranial measures, including intracranial compliance and pressure, were measured by magnetic resonance imaging (MRI) in 36 symptomatic CMI subjects (28 female, 37 ± 11 years) and 37 control subjects (24 female, 36 ± 12 years). The CMI group was further divided based on symptomatology into "typical" and "atypical" subgroups.
Ten of the 20 morphologic and physiologic measures were significantly different between the CMI and the control cohorts. These parameters also had less variability and stronger significance in the typical CMI compared with the atypical. The measures with the most significance were clival and supraocciput lengths, PCF crowdedness, normalized PCF volume, 4th ventricle volume, maximal cord displacement (P < .001), and MR measure of intracranial pressure (P = .007). Multivariate testing identified cord displacement, PCF crowdedness, and normalized PCF as the strongest discriminator subset between CMI and controls. MR measure of intracranial pressure was higher in the typical CMI cohort compared with the atypical.
The identified 10 complementing morphological and physiological measures provide a more complete and symptomatology-relevant characterization of CMI than tonsillar herniation alone.
有充分文献记载，除扁桃体疝外，I型Chiari畸形（CMI）与较小的后颅窝（PCF）以及颅颈交界处脑脊液（CSF）流动和组织运动改变有关。
本研究评估PCF容积测定与CSF及组织动力学之间的关系，以实现基于联合成像的CMI形态学 - 生理学特征描述。采用多变量分析来确定最能将CMI与健康队列区分开的参数子集。
通过磁共振成像（MRI）测量了36例有症状的CMI受试者（28名女性，37±11岁）和37名对照受试者（24名女性，36±12岁）的11项PCF长度和容积指标，包括拥挤程度和第四脑室容积，4项颅颈交界处CSF和脊髓运动指标，以及5项全脑指标，包括颅内顺应性和压力。CMI组根据症状进一步分为“典型”和“非典型”亚组。
CMI组与对照组之间的20项形态学和生理学指标中有10项存在显著差异。与非典型CMI相比，这些参数在典型CMI中的变异性更小，显著性更强。最具显著性的指标是斜坡和枕骨上长度、PCF拥挤程度、标准化PCF容积、第四脑室容积、最大脊髓位移（P <.001）以及颅内压的MR测量值（P =.007）。多变量测试确定脊髓位移、PCF拥挤程度和标准化PCF是CMI与对照组之间最强的鉴别指标子集。典型CMI队列中的颅内压MR测量值高于非典型队列。
所确定的10项互补的形态学和生理学指标比单独的扁桃体疝能提供更完整且与症状相关的CMI特征描述。
