Novel Assessment of Cerebrospinal Fluid Dynamics by Time-Spatial Labeling Inversion Pulse Magnetic Resonance Imaging in Patients with Chiari Malformation Type I.

Abstract

We investigated cerebrospinal fluid (CSF) dynamics at the craniocervical junction (CCJ) using Time-SLIP magnetic resonance imaging to demonstrate the significance of ventral and dorsal combined CSF dynamics in assessing CSF flow disturbance in patients with Chiari malformation type I. Fifteen examinations were performed in 9 cases of CM-I (3 female patients; mean age, 24.7 years; age range, 11-46 years) before or after craniocervical decompression. The longitudinal maximum movement of the caudal edge of tagged midsagittal CSF at the CCJ was measured as length of motion (LOM), and total on the ventral and dorsal sides was defined as total LOM. In 8 conditions, where it was concluded that no craniocervical decompression was necessary or where symptoms improved following craniocervical decompression based on the clinical symptoms, total LOM was 49.8 ± 13.1 mm. In contrast, in the 7 cases where craniocervical decompression was mandatory, total LOM was 23.2 ± 9.2 mm. Significant differences were identified between the 2 groups. Total LOM <35.0 mm resulted to indicate the insufficiency of CSF dynamics, because it corresponded to the necessity of craniocervical decompression based on patients' symptoms. Time-SLIP MRI enabled clinicians to use novel dynamic indices, such as CSF motions, in addition to the conventional findings acquired by MRI. In particular, it was essential to examine combined ventral and dorsal CSF dynamics in assessing CSF patency at the CCJ in patients with CM-I.