Hankinson Todd C, Tuite Gerald F, Moscoso Dagmara I, Robinson Leslie C, Torner James C, Limbrick David D, Park Tae Sung, Anderson Richard C E
Pediatric Neurosurgery, Children's Hospital Colorado, University of Colorado Anschutz Medical Campus, and.
Department of Neurosurgery, University of Colorado School of Medicine, Aurora, Colorado.
J Neurosurg Pediatr. 2017 Aug;20(2):170-175. doi: 10.3171/2017.3.PEDS16604. Epub 2017 May 19.
OBJECTIVE The distance to the ventral dura, perpendicular to the basion to C2 line (pB-C2), is commonly employed as a measure describing the anatomy of the craniovertebral junction. However, both the reliability among observers and the clinical utility of this measurement in the context of Chiari malformation Type I (CM-I) have been incompletely determined. METHODS Data were reviewed from the first 600 patients enrolled in the Park-Reeves Syringomyelia Research Consortium with CM-I and syringomyelia. Thirty-one cases were identified in which both CT and MRI studies were available for review. Three pediatric neurosurgeons independently determined pB-C2 values using common imaging sequences: MRI (T1-weighted and T2-weighted with and without the inclusion of retro-odontoid soft tissue) and CT. Values were compared and intraclass correlations were calculated among imaging modalities and observers. RESULTS Intraclass correlation of pB-C2 demonstrated strong agreement between observers (intraclass correlation coefficient [ICC] range 0.72-0.76). Measurement using T2-weighted MRI with the inclusion of retro-odontoid soft tissue showed no significant difference with measurement using T1-weighted MRI. Measurements using CT or T2-weighted MRI without retro-odontoid soft tissue differed by 1.6 mm (4.69 and 3.09 mm, respectively, p < 0.05) and were significantly shorter than those using the other 2 sequences. Conclusions pB-C2 can be measured reliably by multiple observers in the context of pediatric CM-I with syringomeyelia. Measurement using T2-weighted MRI excluding retro-odontoid soft tissue closely approximates the value obtained using CT, which may allow for the less frequent use of CT in this patient population. Measurement using T2-weighted MRI including retro-odontoid soft tissue or using T1-weighted MRI yields a more complete assessment of the extent of ventral brainstem compression, but its association with clinical outcomes requires further study.
目的 垂直于颅底至C2线（pB - C2）测量到腹侧硬脑膜的距离，通常被用作描述颅颈交界区解剖结构的一种方法。然而，观察者之间的可靠性以及该测量方法在I型 Chiari 畸形（CM - I）背景下的临床实用性尚未完全确定。方法 回顾了Park - Reeves脊髓空洞症研究联盟纳入的前600例患有CM - I和脊髓空洞症患者的数据。确定了31例同时有CT和MRI研究可供审查的病例。三位儿科神经外科医生使用常见的成像序列独立确定pB - C2值：MRI（T1加权和T2加权，包括或不包括齿突后软组织）和CT。比较了这些值，并计算了成像方式和观察者之间的组内相关性。结果 pB - C2的组内相关性显示观察者之间有很强的一致性（组内相关系数[ICC]范围为0.72 - 0.76）。使用包含齿突后软组织的T2加权MRI测量与使用T1加权MRI测量无显著差异。使用不包括齿突后软组织的CT或T2加权MRI测量相差1.6毫米（分别为4.69毫米和3.09毫米，p < 0.05），且明显短于使用其他两种序列的测量值。结论 在患有脊髓空洞症的儿科CM - I患者中，多位观察者可以可靠地测量pB - C2。使用不包括齿突后软组织的T2加权MRI测量值与使用CT获得的值非常接近，这可能使该患者群体中CT的使用频率降低。使用包括齿突后软组织的T2加权MRI或使用T1加权MRI测量能更全面地评估腹侧脑干受压程度，但其与临床结果的关联需要进一步研究。
