Cerebrospinal fluid dynamics analysis using Time Spatial Labeling Inversion pulse (Time-SLIP) MR imaging in mice

Abnormalities in cerebrospinal fluid (CSF) dynamics cause diverse conditions, such as hydrocephalus and scoliosis, but the underlying mechanism is still unknown. Methods to study CSF dynamics in small animals have not been established due to the lack of an evaluation system. Therefore, the purpose of this research is to to establish the time-spatial labelling inversion pulse (Time-SLIP) MRI technique for the evaluation of CSF dynamics in mice. We performed the Time-SLIP technique on 10 wild-type mice and 20 Tiptoe walking Yoshimura (TWY) mice, a mouse model of ossification of the posterior longitudinal ligament (OPLL). We defined the Stir Distance as the distance of CSF stirring and calculated the mean ± standard deviation. The intraclass correlation coefficient of the intraobserver reliabilities was also calculated. Furthermore, in TWY mice, the correlation coefficient between Stir Distance and Canal Stenosis Ratio (CSR) was calculated. The Stir Distance was significantly lower in TWY mice (p0.90) and there was a strongly negative correlation between Stir Distance and CSR in TWY mice (>-0.80). In this study, we established the Time-SLIP technique in experimental mice. This technique allows a better understanding of CSF dynamics in small laboratory animals.