Brain abnormalities in myalgic encephalomyelitis/chronic fatigue syndrome: Evaluation by diffusional kurtosis imaging and neurite orientation dispersion and density imaging.

Background: Diffusional kurtosis imaging (DKI) and neurite orientation dispersion and density imaging (NODDI) metrics provide more specific information regarding pathological changes than diffusion tensor imaging (DTI).

Purpose: To detect microstructural abnormalities in myalgic encephalomyelitis (ME) / chronic fatigue syndrome (CFS) patients by using DKI and NODDI metrics.

Study Type: Prospective.

Population: Twenty ME/CFS patients and 23 healthy controls were recruited.

Field Strength/sequence: Three-b value DWI (b-values = 0, 1000, and 2000 sec/mm ) and 3D T -weighted images were at 3.0T.

Assessment: Mean kurtosis (MK), neurite density index (NDI), orientation dispersion index (ODI), fractional anisotropy (FA), and mean diffusivity (MD) were calculated.

Statistical Testing: The two-sample t-test analysis in SPM12 software was used to compare the differences between ME/CFS and control groups.

Results: In the ME/CFS patients, we observed significant FA decreases in the genu of the corpus callosum and the anterior limb of the right internal capsule (P < 0.05), but no significant difference in MD (P = 0.164); there were also significant MK decreases in the right frontal area, anterior cingulate gyrus, superior longitudinal fasciculus (SLF), and left parietal area (P < 0.05). Significant NDI decreases were observed in the right posterior cingulate gyrus, SLF, and left frontal area of the ME/CFS patients (P < 0.05). Significant ODI decreases were seen in the bilateral occipital areas, right superior temporal gyrus, the anterior limb of internal capsule, and the posterior cingulate gyrus (P < 0.05), and significant ODI increases were revealed in the bilateral occipital and right temporal areas (P < 0.05).

Data Conclusion: Right SLF abnormalities may be a diagnostic marker for ME/CFS.

Level Of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:818-824.