Department of Veterinary Clinical Sciences, Royal Veterinary College, University of London, Hawkshead Lane, North Mymms, Hertfordshire AL97TA, United Kingdom.
Vet J. 2013 Oct;198(1):88-91. doi: 10.1016/j.tvjl.2013.05.017. Epub 2013 Jun 14.
Canine Chiari-like malformation (CM) is characterised by herniation of part of the cerebellum through the foramen magnum. In humans with Chiari type I malformation (CM-I), abnormal pulsation of the cerebellum during the cardiac cycle has been documented and is pivotal to theories for the pathogenesis of syringomyelia (SM). In this retrospective study, cardiac-gated cine balanced fast field echo (bFEE) magnetic resonance imaging (MRI) was used to assess pulsation of the brain in dogs and to objectively measure the degree of cerebellar pulsation with the neck in a flexed position. Overall, 17 Cavalier King Charles Spaniels (CKCS) with CM, including eight with SM and nine without SM, were compared with six small breed control dogs. Linear regions of interest were generated for the length of cerebellar herniation from each phase of the cardiac cycle and the degree of cerebellar pulsation was subsequently calculated. Age, bodyweight and angle of neck flexion were also compared. CKCS with CM and SM had significantly greater pulsation of the cerebellum than control dogs (P=0.003) and CKCS with CM only (P=0.031). There was no significant difference in age, bodyweight and angle of neck flexion between the three groups. Cardiac-gated cine bFEE MRI permitted the dynamic visualisation of cerebellar pulsation in dogs. These findings support the current theories regarding the pathogenesis of SM secondary to CM and further highlight the similarities between canine CM and human CM-I.
犬小脑扁桃体下疝畸形（CM）的特征是小脑的一部分通过枕骨大孔疝出。在 Chiari 型 I 畸形（CM-I）的人类中，已经记录到小脑在心动周期中的异常搏动，这对脊髓空洞症（SM）发病机制的理论至关重要。在这项回顾性研究中，使用心脏门控电影平衡快速场回波（bFEE）磁共振成像（MRI）评估犬的大脑搏动，并在颈部弯曲位置客观测量小脑搏动的程度。总体而言，17 只患有 CM 的骑士查理王小猎犬（CKCS），包括 8 只患有 SM 和 9 只没有 SM 的，与 6 只小型犬对照犬进行了比较。从心动周期的每个阶段生成小脑疝出的线性感兴趣区，并随后计算小脑搏动的程度。还比较了年龄、体重和颈部弯曲角度。患有 CM 和 SM 的 CKCS 的小脑搏动明显大于对照犬（P=0.003）和仅患有 CM 的 CKCS（P=0.031）。三组之间的年龄、体重和颈部弯曲角度没有显著差异。心脏门控电影 bFEE MRI 允许对犬的小脑搏动进行动态可视化。这些发现支持了关于 CM 继发 SM 发病机制的当前理论，并进一步强调了犬 CM 和人类 CM-I 之间的相似性。
