Related Experiment Video
Updated: Feb 5, 2026
09:33
Diffusion Tensor Magnetic Resonance Imaging in the Analysis of Neurodegenerative Diseases
Published on: July 28, 2013
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Comparing Glymphatic Function Measures: Diffusion Tensor Image Analysis Along Perivascular Spaces (DTI-ALPS) versus
Ingrid Mossige1,2,3, Lars M Valnes1,4, Tryggve H Storås1,3
1Department of Physics and Computational Radiology, Division of Radiology and Nuclear Medicine, Oslo University Hospital, Sognsvannsveien 21, 0372 Oslo, Norway.
Radiology
|February 3, 2026
Summary
Diffusion-tensor image analysis along the perivascular space (ALPS) shows limited association with glymphatic function markers. This study found sparse cerebrospinal fluid tracer enhancement in ALPS regions, suggesting ALPS may not be a reliable indicator of glymphatic function.
Area of Science:
- Neuroimaging
- Cerebrospinal Fluid Dynamics
- Neurodegenerative Diseases
Background:
- Diffusion-tensor image analysis along the perivascular space (ALPS) is a proposed noninvasive method to assess glymphatic function.
- The validation of ALPS against established glymphatic function measures remains limited.
Purpose of the Study:
- To evaluate ALPS indexes in different participant groups.
- To compare ALPS indexes with cerebrospinal fluid (CSF) tracer enrichment and clearance measured by intrathecal contrast-enhanced MRI (gMRI).
Main Methods:
- Secondary analysis of a prospective observational study involving 56 participants with CSF disorders and reference individuals.
- Acquisition of MRI and diffusion-tensor imaging (DTI) scans before and after intrathecal gadobutrol injection.
- Analysis of ALPS indexes and comparison with CSF tracer enrichment at 24 and 48 hours using regression analysis.
Main Results:
- The ALPS index was significantly lower in the idiopathic normal pressure hydrocephalus (iNPH) group compared to the reference group.
- A negative association was observed between the ALPS index and CSF tracer enrichment at 24 hours in deep white matter.
- CSF tracer enrichment in ALPS regions of interest was minimal (10%), contrasting with substantial cortical enrichment (68-81%).
Conclusions:
- CSF tracer enhancement within ALPS regions of interest was sparse across all participant groups.
- The association between the ALPS index and gMRI markers of glymphatic function was found to be limited.
- Further research is needed to validate ALPS as a reliable measure of glymphatic function.
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