Diffusion Tensor Imaging And Resting State Functional Magnetic Resonance Imaging In ICU Patients With Delirium

Objective:To conduct comprehensive analysis on the cerebral function of patients with delirium in ICU using the cerebral function imaging technology under resting state of patients with delirium and fractional anisotropy(FA)of each cerebral region as well as mean diffusivity(MD)of using DTI technology with the aim of providing visual evidence for the diagnosis,treatment assessment of patients with delirium and new clue for exploring the mechanism of ICU delirium from the perspective of function imaging and laying the foundation for improving the long-term prognosis of patients with delirium.Methods: Patients with delirium in ICU in our hospital from January to December 2017 were included and MRI under resting state and diffusion tensor imaging scan technology were conducted.The experimental data was recorded and data post-processing was done to analyze the cerebral function network and FA,MD value of each cerebral region under resting state.15 patients with delirium and 15 healthy persons with the same age,gender and education level were selected and all the subjects received MRI to obtain the fMRI under resting state and diffusion tensor imaging(DTI)data.The TI data was processed by FSL software to extract the FA/MD value of each cerebral region.The regional homogeneity(ReHo)analysis method was used to evaluate the abnormal variations of cerebral function under resting state of patients with delirium.The differences of ReHo and FA and MD value between the two groups were analyzed by independent t-test.By analyzeing whether the decrease of ReHo of patients with delirium was associated with ICDSC value,the cerebral region with decreased ReHo was selected as the ROI and used in the correlation analysis with ICDSC value.Results: 1.ReHo value between patients with delirium and healthy subjectsCompared with the healthy patients,the local consistency was increased at pons,right hippocampus,epencephalon,midbrain and corpus striatum(P<0.05,Alphasimcarlibration),however that was decreased at the upper gyrus of bilateral frontal lobes,median gyrus of bilateral frontal lobes,lower gyrus of left frontal lobe,parietal lobe and temporal lobe.2.Correlation analysis of ICDSC and ReHo between patients with delirium and healthy subjectsThe ReHo value of the medial frontal gyrus is negative associated with ICDSC score of patients with delirium(r = 0.7944,P= 0.01).3.Comparison of FA between patients with delirium and healthy personsCompared with the healthy subjects,the FA values were decreased at the left encephalon,left and right frontal lobe,left temporal lobe,callosum and left hippocampus(P<0.05,Alphasimcarlibration).4.Comparison of MD between patients with delirium and healthy subjectsCompared with healthy subjects,MD values were increased at the medial frontal gyrus,upper gyrus of right temporal lobe,anterior cingutate,left and right insular lobe and left caudate nucleus of patients(P<0.05,Alphasimcarlibration).Conclusion: 1.The cerebral function activities of multiply encephaic regions are abnormal under resting state.The ReHo value of medial frontal gyrus is negative associated with ICDSC score of patients with delirium.2.There are multiply encephaic regions' s structural injuries in patients with delirium.It is suggested that the abnormal medial frontal gyrus resting brain function is closely related to the occurrence of delirium.3.We speculate that the risk and mechanism of delirium is closely associated with the abnormality of cerebral regions like frontal lobe,temporal lobe,callosum,hippocampus and epencephalon.