The pathogenesis of syringomyelia in association with Chiari malformation Type I (CM-I) is unclear. Studies of patients with CM-I have shown alterations in the CSF velocity profile using cardiac-gated cine phase-contrast MRI, and computational simulations have demonstrated that temporal features of the CSF pulse could contribute to syrinx development or enlargement. Few studies have reported temporal characteristics of the CSF profile, and few studies have reported on CM-I patients with and without syringomyelia separately. This study was performed to determine whether specific temporal features of the CSF flow profile may underlie the development or enlargement of a syrinx in patients with CM-I.
Ten healthy volunteers and 18 patients with CM-I with (8 patients) and without (10 patients) syringomyelia were studied using cardiac-gated cine phase-contrast MRI, measuring the maximum CSF velocities in the cranial and caudal directions, the timing of these maximums relative to the cardiac cycle time, the timing of caudal flow onset, timing of cranial flow onset, and the duration of caudal flow.
The caudal CSF flow was significantly faster (p ≤ 0.01) and earlier (p < 0.02) in patients without syringomyelia than in healthy volunteers and patients with syringomyelia. There were no significant differences in the CSF velocities between patients with syringomyelia and healthy volunteers. Patients with CM-I who had syringomyelia had a significantly later start of caudal CSF flow (p < 0.01) and earlier maximum cranial velocity (p = 0.03) than healthy volunteers, but the relative durations of caudal and cranial flow were not significantly different between any of the groups.
The significantly earlier arrival and earlier peak velocity of caudal CSF flow may underlie the development of syringomyelia in patients with CM-I, and after a syrinx develops the CSF flow profile appears to stabilize.
Abbreviations used in this paper:CM-I = Chiari malformation Type I; SAS = subarachnoid space.
Address correspondence to: Elizabeth C. Clarke, Ph.D., B.E., B.Sc., Biomechanics Laboratory, Level 10, Kolling Institute, Building 6, Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia. email: Elizabeth.firstname.lastname@example.org.
Please include this information when citing this paper: published online March 15, 2013; DOI: 10.3171/2013.2.JNS12759.
BilstonLEStoodleyMAFletcherDF: The influence of the relative timing of arterial and subarachnoid space pulse waves on spinal perivascular cerebrospinal fluid flow as a possible factor in syrinx development. Laboratory investigation. J Neurosurg112:808–8132010
HaughtonVMKorosecFRMedowJEDolarMTIskandarBJ: Peak systolic and diastolic CSF velocity in the foramen magnum in adult patients with Chiari I malformations and in normal control participants. AJNR Am J Neuroradiol24:169–1762003
RennelsMLGregoryTFBlaumanisORFujimotoKGradyPA: Evidence for a ‘paravascular’ fluid circulation in the mammalian central nervous system, provided by the rapid distribution of tracer protein throughout the brain from the subarachnoid space. Brain Res326:47–631985