Quantitative assessment of white matter damage caused by delayed neuropsychiatric sequelae after carbon monoxide poisoning with diffusion kurtosis imaging

Objective To investigate the value of quantitative evaluation in white matter damage caused by delayed neuropsychiatric sequelae (DNS) after carbon monoxide poisoning (CO) with diffuse kurtosis imaging (DKI). Methods A prospective study was conducted from November 2016 to February 2019 in 28 patients diagnosed as having DNS after CO poisoning and 30 healthy controls in our hospital. DKI scans were performed within 7 d of onset and DKI-derived parameters (9 regions of interest), including mean kurtosis (MK), axial kurtosis (AK), and radial kurtosis (RK), were obtained. Mini Mental State Examination Scale (MMSE), Barthel Index, Verbal Fluency Test (VFT), and Digital Breadth Test (DST) were performed on both subjects to conduct neurocognitive assessment; multivariate regression analysis was performed to determine the statistical relations of scores of above neurocognitive scales with AK values of ROIs. Results As compared with those in the control group,the MK, AK and RK values in all ROIs showed an increased trend in DNS group; among which, the anterior semioval center, posterior semioval center and frontal lobe enjoyed the most obvious increase, with significant differences (P<0.05). In the genu of corpus callosum, body of corpus callosum and parietal lobe, the AK value of DNS group was significantly higher than that in the controls (P<0.05). Except for temporal lobe and occipital lobe, area under the curve (AUC) of AK value of other ROIs in diagnosing DNS was larger than that of RK and MK values of other ROIs; AK value of anterior semioval center (AUC=0.802, P=0.000), posterior semioval center (AUC=0.785, P=0.000), frontal lobe (AUC=0.749, P=0.001), genu of corpus callosum, (AUC=0.730, P=0.003), parietal lobe (AUC=0.699, P=0.009) and body of corpus callosum (AUC=0.654, P=0.045) had better performance than RK and MK in diagnosing DNS, with statistically significant differences (P<0.05). Multivariate regression analysis results show that the DST value (reverse) is the independent influencing factors of AK values of anterior semioval center, genu of corpus callosum, and frontal lobe; VET (vegetable) is the independent influencing factors of AK values of body of corpus callosum, age is the independent influencing factors of AK values of posterior semioval center, splenium of corpus callosum, and frontal, temporal and occipital lobes; and education is the independent influencing factors of AK values of temporal lobe. Conclusion DKI can quantitatively evaluate the microstructural damage of white matter caused by DNS, and the increase of AK is related to the decrease of neurological function in patients with DNS. Key words: Delayed neuropsychiatric sequelae; White matter; Diffusion kurtosis imaging; Magnetic resonance imaging