Letters CSF Flow Dynamics in Chiari I Malformation

We read with interest the article by Hofmann et al (1) in the January 2000 issue of the AJNR. In this study, authors used phase-contrast imaging in the axial plane to measure quantitatively the CSF and spinal cord motion at the C2 level in 18 pa-tients with Chiari I malformation and in 18 healthy subjects. The authors concluded that in patients with Chiari I malformation, foramen magnum ob-struction leads to increased systolic spinal cord mo-tion and impaired diastolic spinal cord recoil and diastolic CSF motion. Although they found their results of spinal cord motion to be in keeping with one of our earlier studies (2), they concluded that their observations of CSF flow dynamics were dif-ferent from our subsequent quantitative study (3