Diffusional kurtosis imaging in hydrocephalus.

Abstract Purpose Diffusional kurtosis imaging is an advanced diffusion magnetic resonance imaging method that yields, in addition to conventional diffusion information, non-Gaussian diffusion effects, which may allow a more comprehensive characterization of tissue microstructure. The purpose of this study is to use diffusional kurtosis to assess white matter integrity in patients with hydrocephalus and to determine whether changes in kurtosis correlate with the severity of hydrocephalus and leukoaraiosis (LA), a commonly seen comorbidity in hydrocephalus. Methods 26 patients with imaging evidence of hydrocephalus and 26 age- and sex- matched subjects with normal ventricular size were retrospectively analyzed. Standard diffusion tensor imaging and diffusional kurtosis metrics were compared between the two groups. Correlation between kurtosis and severity of hydrocephalus and presence and severity of LA was determined. Results Hydrocephalus patients relative to controls demonstrated statistically significant decrease in all kurtosis metrics in most brain regions studied. The severity of hydrocephalus was associated with greater decrease in kurtosis in the corpus callosum. There was more LA in the hydrocephalus group, and severity of LA was associated with decrease in kurtosis. After controlling for the degree of LA, kurtosis was still decreased in hydrocephalus relative to the controls. Conclusion Diffusional kurtosis imaging detects microstructural changes in the white matter of patients with hydrocephalus. Our results suggest that hydrocephalus plays a role in altering white matter integrity.