A Test-Retest Study of Single- and Multi-Delay pCASL for Choroid Plexus Perfusion Imaging in Healthy Subjects Aged 19 to 87 Years

Motivation: Perfusion of the choroid plexus (ChP) is crucial for maintaining brain homeostasis and glymphatic function,which is significantly influenced by age. Goal(s): Our goal was to perform a comprehensive and quantitative comparison between single-delay and multi-delay ASL measurements of ChP perfusion while investigating influence of age. Approach: 28 healthy subjects underwent test-retest scans ~1 week apart.CBF/ATT ChP values and grey/white matter were quantified to evaluate the test-retest reliability. Results: CBF in ChP showed good test-retest repeatability and a significant negative correlation with age.ATT in ChP was greater than 2sec in ~12.85% of voxels,causing around 10% CBF underestimation when ASL signals were acquired with single-PLD. Impact: Single and multi-delay ASL showed similar test-retest repeatability for measuring ChP perfusion. However, the underestimation of ATT with single-delay ASL affects the accuracy of the results. Multi-delay ASL with model-fitting analysis is recommended for measuring ChP perfusion.