Glymphatic system evaluation using diffusion tensor imaging in patients with traumatic brain injury.

Area of Science:

• Neuroscience
• Radiology
• Biomedical Engineering

Background:

• Glymphatic system dysfunction is implicated in traumatic brain injury (TBI) pathophysiology.
• Animal models suggest impaired glymphatic clearance after TBI.
• Evaluating human glymphatic function non-invasively is crucial for understanding TBI.

Purpose of the Study:

• To assess human glymphatic system activity in TBI patients.
• To utilize the Diffusion Tensor Image-Analysis aLong the Perivascular Space (DTI-ALPS) method for glymphatic evaluation.
• To correlate glymphatic activity with TBI severity and radiological findings.

Main Methods:

• Retrospective analysis of 89 TBI patients and 34 healthy controls.
• Magnetic Resonance Imaging (MRI) with Diffusion Tensor Imaging (DTI) to calculate the ALPS index.
• Statistical analysis including Wilcoxon rank-sum test, ANOVA, and multivariate logistic regression.

Main Results:

• Patients with TBI exhibited significantly lower ALPS index values compared to healthy controls (P < 0.0001).
• ALPS index differed significantly across controls and TBI severity groups (mild/moderate-to-severe).
• Subarachnoid hemorrhage and diffuse axonal injury correlated with reduced ALPS index; a weak positive correlation was found with Glasgow Coma Scale (GCS) scores.

Conclusions:

• The DTI-ALPS method is a valuable tool for assessing glymphatic system impairment in TBI.
• Quantification of glymphatic activity using DTI-ALPS aids in understanding TBI.
• This non-invasive technique offers a promising approach for clinical evaluation of TBI patients.