Objective: The purpose of this study was to determine if there is a difference in the caudal extent of brain stem herniation and the degree of cervicomedullary deformity between symptomatic and asymptomatic Chiari II patients. Methods: Magnetic resonance imaging and the clinical presentation of 14 symptomatic and 59 asymptomatic patients were analyzed. The level of the cervicomedullary deformity below the foramen magnum was measured in both groups. The level of the deformity was identified by the cervical vertebral body or disc space level. Results and Conclusion: Review of our results shows no obvious relationship between the level of cervicomedullary deformity and the presenting symptoms or the outcome after surgical decompression. We conclude that the level of herniation and the cervicomedullary deformity is not a reliable marker to determine which patients may become symptomatic and require decompression or to determine prognosis.

1.
Wolpert SM, Anderson M, Scott RM, Kwan ES, Runge VM: Chiari II malformation: MR imaging evaluation. AJNR Am J Neuroradiol 1987;8:783–792.
2.
El Gammal T, Mark EK, Brooks BS: MR imaging of Chiari II malformation. AJNR Am J Neuroradiol 1987;8:1037–1044.
3.
Curnes JT, Oakes WJ, Boyko OB: MR imaging of hindbrain deformity in Chiari II patients with and without symptoms of brainstem compression. AJNR Am J Neuroradiol 1989;10:293–302.
4.
Emery JL, MacKenzie N: Medullo-cervical dislocation deformity (Chiari II deformity) related to neurospinal dysraphism (meningomyelocele). Brain 1973;96:155–162.
5.
Iskandar BJ, Oakes WJ: Chiari malformations; in Albright AL, Pollack IF, Adelson PD (eds): Principles and Practice of Pediatric Neurosurgery. New York, Thieme, 1999.
6.
Wolpert SM, Scott RM, Platenberg C, Runge VM: The clinical significance of hindbrain herniation and deformity as shown on MR images of patients with Chiari II malformation. AJNR Am J Neuroradiol 1988;9:1075–1078.
7.
Gilbert JN, Jones KL, Rorke LB, Chernoff GF, James HE: Central nervous system anomalies associated with meningomyelocele, hydrocephalus and the Arnold-Chiari malformation: Reappraisal of theories regarding the pathogenesis of posterior neural tube closure defects. Neurosurgery 1986;18:559–564.
8.
Cameron AH: The Arnold-Chiari and other neuro-anatomical malformations associated with spina bifida. J Pathol Bacteriol 1957;73:195–211.
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