MUSE and PROPELLER DWI for ADC in parasagittal dura: insights from high-resolution and reduced-distortion DWI.

The parasagittal dura (PSD) is a thin channel along the sagittal sinus vein at the brain's upper convexities. Previous studies have shown that cerebrospinal fluid (CSF) flows directly into the PSD, with PSD dimensions and tracer clearance rates associated with aging and brain disorders. Since slow lymphatic drainage is sensitive to water diffusion, PSD circulation may be evaluated using diffusion-weighted imaging (DWI). However, traditional echo-planar DWI (EP-DWI) suffers from low resolution and image distortion, limiting its application to PSD assessment. This study employed high-resolution Multiplexed Sensitivity Encoding (MUSE) DWI and Periodically Rotated Overlapping Parallel Lines with Enhanced Reconstruction (PROPELLER) DWI to investigate PSD water diffusion. These advanced techniques reduce image distortion while enhancing spatial resolution. Our results demonstrated that PSD structures are clearly visible on high-resolution DWI and apparent diffusion coefficient (ADC) maps, correlating with PSD locations identified on T2 FLAIR imaging. In addition, mean ADC values of PSD (1843.1-2062.2 × 10^- 6 mm²/sec) were higher than those of gray and white matter but lower than CSF. These findings highlight the potential of MUSE and PROPELLER DWI for assessing PSD diffusion, offering a promising non-invasive tool for studying PSD circulation and its role in neurological disorders.