The Value Of Diffusion Kurtosis Imaging In Evaluating The Mild Cognitive Impairment In Occupational Aluminum Workers

Objective:To investigate the diagnostic value of diffusion kurtosis imaging(DKI)in mild cognitive impairment(MCI)of aluminum workers,and the correlation between DKI parameters and cognitive function score,plasma aluminum concentration in corresponding areas.Methods:Twenty-eight MCI patients and twenty-five normal control(NC)were collected from aluminum workers who had physical examination in our hospital from October 2014 to August 2017.The Montreal Cognitive Assessment(Mo CA)and plasma aluminum concentration were measured in every case.All patients performed conventional MRI and DKI sequence.The region of interest(ROI)were selected in bilateral hippocampus,bilateral substantia nigra,bilateral red nucleus,bilateral thalamus,bilateral anterior cingulate gyrus,splenium and genu of the corpus callosum,bilateral frontal white matter,bilateral parietal white matter and bilateral temporal white matter and then measured DKI parameters.The differences of DKI parameters between the two groups were compared.The correlations between DKI parameters and Mo CA score,plasma aluminum concentration were tested using Spearman correlation.Receiver operating characteristic(ROC)test was conducted to assess the diagnostic performance of different parameters of regions.Results:1.The results of DKI: Compared with the NC group,MK value in MCI group significantly decreased in the right hippocampus,left substantia nigra,right frontal lobe and bilateral parietal lobe,increased in the right thalamus;Ka value decreased in the right substantia nigra and left red nucleus;Kr value decreased in the left substantia nigra and bilateral parietal lobe,increased in the right thalamus(all P<0.05).Compared with the NC group,MD value in MCI group markedly increased in the right hippocampus and right red nucleus,FA value decreased in the left substantia nigra(all P<0.05).2.The results of correlation: the MK value in the right hippocampus,left substantia nigra and right frontal lobe,the Kr value in the left substantia nigra and bilateral parietal lobe,the MD value in the right hippocampus,the FA value in the left substantia nigra showed correlation with Mo CA score,among which,the MK value in the right hippocampus has the strongest correlation with the Mo CA score(r=0.744,P<0.001),followed by the MD value in the right hippocampus(r=-0.497,P<0.001).No correlation was found between the selected ROI and the plasma aluminum concentration.3.The results of ROC analysis: For the diagnosis of MCI,the MK value in the right hippocampal showed highest accuracy,sensitivity and the largest AUC.The AUC for the MK value in the right hippocampal was larger than the corresponding MD value(AUC=0.924,0.737,P<0.05);the AUC for the MK value in the right hippocampal was larger than the MK value in the right frontal lobe and the MK value in the left substantia nigra(AUC=0.924,0.670,P<0.05)(AUC=0.924,0.711,P<0.05).Conclusion:1.DKI can be used in the differential diagnosis of MCI and NC in aluminum workers.The MK value in the right hippocampal has the highest diagnostic efficiency.2.DKI could effectively predict the clinical cognitive status of MCI patients.3.DKI is more sensitive than DTI in the early diagnosis of MCI.4.The plasma aluminum concentration in MCI was higher than that in NC,the correlation between DKI parameters and plasma aluminum concentration was not found..