Use of multi-modal non-contrast MRI to predict functional outcomes after stroke: A study using DP-pCASL, DTI, NODDI, and MAP MRI

Neuroimage Clin. 2025:45:103742. doi: 10.1016/j.nicl.2025.103742. Epub 2025 Jan 24.

Abstract

Purpose: This study aims to assess whether water exchange rate (kw), a surrogate for blood-brain barrier (BBB) permeability, is associated with functional outcomes in patients with acute ischemic stroke (AIS).

Methods: We studied 22 AIS patients enrolled from 1/2022 to 4/2024 who underwent multi-modal non-contrast imaging on a 3.0-Tesla scanner, including DP-pCASL, DTI, NODDI and MAP imaging. For each parametric map, the intensity and standard deviation (SD) were calculated for the infarcted region. The diffusion maps included were b0, Fractional Anisotropy (FA), Mean Diffusivity (MD), Intra-cellular Volume Fraction (ICVF), Free Water Fraction (FWF), and Orientation Dispersion Index (ODI), q-Space Mean Square Displacement (QMSD), Return-to-Axis Probability (RTAP), Return-to-Plane Probability (RTPP), Return-to-Origin Probability (RTOP), Propagator Anisotropy (PA), and non-Gaussianity (NG). The perfusion-based maps were cerebral blood flow (CBF), arterial transit time (ATT), and kw. The outcome variable was modified Rankin Scale (mRS).

Results: Twenty-two patients were included. The average age was 69.5 ± 13.5, the mean NIHSS of 12.4 ± 7.7, and the median infarct of 25.7 (8.4-98.8) ml. Multivariable linear regression identified lower kw (β = -0.029, p = 0.041), longer time to MRI (β = 0.012, p = 0.013) and larger stroke volume (β = 0.014, p = 0.006) as predictive of higher mRS. Higher CBF (β = 0.660, p = 0.003) and RTAP (β = 1.528, p = 0.010), and lower SD RTAP (β = -0.709, p = 0.016), RTPP (β = -2.132, p = 0.006), and NG (β = -1.036, p = 0.011) were identified as most predictive of kw through multivariable linear regression analysis.

Conclusions: Lower kw is predictive of higher mRS in patients with AIS. Increasing CBF and RTAP and lower SD RTAP, RTPP, and NG were correlated with higher kw.

Keywords: Acute Ischemic Stroke (AIS); Blood-Brain Barrier (BBB); Diffusion Tensor Imaging (DTI); Mean Apparent Propagator (MAP) MRI; Neurite Orientation Dispersion and Density Imaging (NODDI); Water Exchange Rate (kw).

MeSH terms

  • Aged
  • Aged, 80 and over
  • Blood-Brain Barrier / diagnostic imaging
  • Diffusion Tensor Imaging / methods
  • Female
  • Humans
  • Ischemic Stroke* / diagnostic imaging
  • Ischemic Stroke* / physiopathology
  • Magnetic Resonance Imaging* / methods
  • Male
  • Middle Aged
  • Multimodal Imaging* / methods
  • Recovery of Function / physiology
  • Stroke* / diagnostic imaging
  • Stroke* / physiopathology