Purpose

To observe modifications in cerebral microstructure in brain small vessel disease using magnetic resonance imaging (MRI) diffusion kurtosis imaging (DKI) and to provide pathogenesis information of this disease from the perspective of radiography.

Material and Methods

Forty-four (33 males and 11 females) diagnosed with brain small vessel disease were recruited as the patient group, and 16 age and education level-matched healthy volunteers (12 males and, 4 females) were recruited as the control group. Routine MR scan were performed for all the subjects on a whole body 3T scanner (Ingenia, Philips Healthcare) with a 16-ch dS head coil. Kurtosis images were acquired with following parameters: TE91ms/TR1000ms, slices 18, b values 1000, 2000 and 32 directions. DKE (Version 2.5.1) was employed to generate kurtosis related parameters. The mean kurtosis (MK), the fractional anisotropy (FA) and the mean diffusion coefficient (MD) of cerebral white matter was compared between two groups in basal ganglia ,thalamus , corona radiata, centrum ovale, and the location beside lateral ventrical , pons and callosum using two sample T test.

Results and Discussions

There was no statistically significant difference in FA value of bilateral thalamas, the posterior limb of the internal capsule, corona, centrum ovale or left basal ganglia between two groups (P>0.05) . FA value of right basal ganglia in the patient group was significantly decreased than that of the control group (P<0.05) (Figure 1) . There was no significant difference in MK value of bilateral basal ganglia, thalamas, the posterior limb of the internal capsule, the location beside lateral ventrical posterious cornu, or the callosum between two groups (P>0.05) . MK value of left corona radiata ，bilateral centrum ovale and pons of the patient group was significantly decreased than that of the control group (P<0.05) (Figure 2). Moreover, no significant difference was observed in MD value of bilateral basal ganglia, the posterior limb of the internal capsule, the location beside lateral ventrical anterior and posterious cornu, callosum, right thalamas , centrum ovale and pons between two groups (P>0.05) . MD value of bilateral corona radiata ，left thalamas and centrum ovale of the patient group was significantly decreased than that of the control group (P<0.05) (Figure 3) . The conventional diffusion parameters were estimated using the mono-exponential model, where the values derived depended on the selection of b-values. As an extension of DTI model, DKI required at least two non-zero b values in more than 15 independent directions. Using a second-order polynomial model, DKI would provide a b-value-independent estimation of the diffusion and kurtosis parameters. Therefore, DKI could be an ideal technique for estimating the restricted diffusion process in vivo, especially in detecting the pathological alterations in neural tissues.

Conclusion

The results suggested that DKI provide sensitive developmental changes in local microstructures in brain small vessel disease. DKI derived diffusion parameters were sensitive to changes in white matter regions with complex fiber arrangements. The atrophy may exist in white matter fiber, which contributes to providing complementary information in the diagnosis of brain small vessel disease.

Acknowledgements

No acknowledgement found.