Kim In-Kyeong, Wang Kyu-Chang, Kim In-One, Cho Byung-Kyu
Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea.
J Korean Neurosurg Soc. 2010 Oct;48(4):375-9. doi: 10.3340/jkns.2010.48.4.375. Epub 2010 Oct 30.
The Chiari 1.5 malformation is defined as a tonsillar herniation within a Chiari I malformation with additional caudal descent of the brainstem through the foramen magnum. We describe a patient with Chiari I malformation who evolved to Chiari 1.5 malformation during longitudinal follow-up. A 15-year-old girl presented with neck pain during exercise for two years. She had been diagnosed with Chiari I malformation with mild hydrocephalus after minor cervical trauma at the age of six years. At that time, she was asymptomatic. After she complained of aggravated neck pain, neuroimaging (nine years after first imaging) revealed caudal descent of the brainstem and syringomyelia in addition to progression of tonsillar herniation. Posterior fossa decompressive surgery resulted in complete resolution of neck pain. Based on neuroimaging and operative findings, she was diagnosed as Chiari 1.5 malformation. Neuroimaging performed seven months after surgery showed an increased anterior-posterior diameter of the medulla oblongata and markedly decreased syringomyelia. This case demonstrates progressive developmental process of the Chiari 1.5 malformation as an advanced form of the Chiari I malformation.
Chiari 1.5畸形被定义为在Chiari I畸形基础上出现扁桃体疝，且脑干通过枕骨大孔进一步向尾端下移。我们描述了一名Chiari I畸形患者，在长期随访过程中进展为Chiari 1.5畸形。一名15岁女孩在运动时颈部疼痛两年。她6岁时因轻度颈椎外伤被诊断为Chiari I畸形伴轻度脑积水，当时无症状。在她主诉颈部疼痛加重后，神经影像学检查（首次成像9年后）显示除扁桃体疝进展外，脑干向尾端下移及脊髓空洞形成。后颅窝减压手术使颈部疼痛完全缓解。根据神经影像学和手术所见，她被诊断为Chiari 1.5畸形。术后7个月的神经影像学检查显示延髓前后径增加，脊髓空洞明显减小。该病例展示了Chiari 1.5畸形作为Chiari I畸形的一种晚期形式的渐进性发展过程。
