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RT Journal Article
SR Electronic
T1 Tapering of the Cervical Spinal Canal in Patients with Chiari I Malformations
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
DO 10.3174/ajnr.A2948
A1 Hirano, M.
A1 Haughton, V.
A1 del Rio, A. Munoz
YR 2012
UL http://www.ajnr.org/content/early/2012/03/08/ajnr.A2948.abstract
AB BACKGROUND AND PURPOSE: Upper cervical spinal canal dimension may have a role in abnormal CSF dynamics in patients with Chiari I malformation. We attempted to measure spinal canal tapering from anteroposterior spinal canal dimensions in patients with Chiari I. MATERIALS AND METHODS: Twenty-one patients with Chiari I malformation, including 12 with syringomyelia and 7 patients with IS were identified from a local registry. Age- and sex-matched control subjects with cervical spine MR imaging findings reported as normal were selected from the PACS. The anteroposterior diameter of the spinal canal was measured at C1-C7 on T2-weighted sagittal MR images. The taper ratio of the spinal canal was calculated with the regression line. Goodness of fit was calculated as R2. Differences between patients with Chiari I and other patients were tested for significance with Kruskal-Wallis tests and multivariate analysis. RESULTS: Taper ratios averaged −0.6 ± 0.3 mm/level in the patients with Chiari and syrinx, −0.4 ± 0.2 mm/level (mean ± 1 SD) in the patients with Chiari without syrinx, and −0.3 ± 0.5 mm/level in the patients with IS; control groups had average taper ratios of −0.3 ± 0.2 mm/level. Mean R2 equaled 0.43. Taper ratios in patients with Chiari and syringomyelia differed significantly from those in the control group (P = .003). Taper ratios in the patients with Chiari without syrinx and in patients with IS did not differ significantly from their matched control groups (P = .60 and 0.76, respectively). CONCLUSIONS: Patients with Chiari I and a syrinx have steeper tapering of the upper cervical spinal canal than matched controls. Abbreviations HDCThereditary disorders of connective tissueIQRinterquartile rangeISidiopathic syringomyeliaSEstandard error