Measuring Aqueduct of Sylvius Cerebrospinal Fluid Flow in Multiple Sclerosis Using Different Software

Area of Science:

• Neuroimaging
• Cerebrospinal Fluid Dynamics
• Medical Software Validation

Background:

• Cerebrospinal fluid (CSF) flow quantification in the Aqueduct of Sylvius (AoS) is crucial for neurological studies.
• Phase-contrast (PC) Magnetic Resonance Imaging (MRI) is a key technique for measuring AoS CSF flow.
• The choice of segmentation software may influence the reliability of PC-MRI derived metrics.

Purpose of the Study:

• To assess the repeatability and reproducibility of AoS CSF flow measures obtained using different software packages.
• To evaluate the impact of software selection on group differentiation, particularly between multiple sclerosis (MS) patients and controls.
• To identify robust PC-MRI derived metrics for clinical application in AoS flow analysis.

Main Methods:

• Analyzed AoS PC-MRI data from 30 individuals with MS and 19 healthy controls.
• Utilized three distinct software packages for AoS segmentation and quantification of cross-sectional area (CSA), average velocity (Vmean), highest velocity (Vmax), flow rate, and volume.
• Assessed repeatability, reproducibility, and inter-software agreement for all derived measures.

Main Results:

• Most variables demonstrated good repeatability, with exceptions in Vmean, flow rate, and volume from one software.
• High agreement was observed in AoS segmentation overlap across different software packages.
• Highest velocity (Vmax) at the diastolic peak significantly differentiated MS patients from controls, irrespective of the software used.

Conclusions:

• Preliminary evaluation of repeatability is recommended before clinical interpretation of AoS PC-MRI findings.
• Vmax appears to be a repeatable and reproducible measure, less susceptible to segmentation variability.
• Vmax is a promising metric for differentiating neurological conditions like MS based on AoS CSF flow dynamics.