Diffusion tensor imaging and resting-state functional magnetic resonance imaging in patients with delirium in intensive care unit / 中华危重病急救医学

Objective:To analyze the brain function of patients with delirium in intensive care unit (ICU) using resting-state functional magnetic resonance imaging (fMRI), further analyze the structural changes in the brain using diffusion tensor imaging (DTI), and explore the correlations of brain function with structural changes in patients with delirium in ICU from a new perspective of functional imaging, provide visual evidence for the diagnosis of delirium.Methods:Patients with delirium admitted to ICU of the Affiliated Hospital of Zunyi Medical University from January 1st to December 31st in 2017 were enrolled as subjects. During the same period, the healthy volunteers who matched the gender, age and education level of the patients with delirium were enrolled as control group. The intensive care delirium screening checklist (ICDSC) scores within 24 hours after ICU admission were recorded. All the subjects were scanned by fMRI and DTI. The abnormal changes in resting-state brain function of the patients with delirium were evaluated by cerebral regional homogeneity (ReHo) data analysis. The DTI data were processed by the FSL software, and the fractional anisotropy (FA) and mean diffusivity (MD) of the brain were extracted, respectively, to evaluate the damage to brain structure. The values of ReHo, FA and MD were compared between the two groups. The ReHo value of brain region with reduced ReHo value of patients with delirium as compared with the healthy volunteers was extracted for Pearson correlation analysis with ICDSC scores.Results:A total of 22 patients with delirium were included. Seven patients who did not cooperate in the examination, used sedatives or had false images in scanning, were excluded. Finally, 15 patients were enrolled in the delirium group, and 15 healthy volunteers in the healthy control group. ① No statistically significant difference was found in gender, age or education time between the two groups. ICDSC score of the delirium group was significantly higher than that of the healthy control group (6.07±1.28 vs. 1.07±0.88, P < 0.01). ② fMRI scanning and analysis results: compared with the healthy control group, the ReHo values of the cerebellum, right hippocampus, striatum, midbrain and pons in the delirium group were significantly increased (all P < 0.05, AlphaSim correction), while the ReHo values of bilateral superior frontal gyrus, bilateral median frontal gyrus, left inferior frontal gyrus, temporal lobe and parietal lobe were significantly lowered (all P < 0.05, AlphaSim correction). Correlation analysis showed that the ReHo value of the left superior frontal gyrus was negatively correlated with ICDSC score in the patients with delirium ( r = -0.794, P < 0.05), indicating that the changes in the functional area of the medial frontal gyrus was most closely related to delirium. ③ DTI scanning and analysis results: compared with the healthy control group, the FA values of the left cerebellum, bilateral frontal lobes, left temporal lobe, corpus callosum and left hippocampus in the delirium group were decreased significantly (all P < 0.05, AlphaSim correction), while the MD values of the medial frontal gyrus, right superior temporal gyrus, anterior cingulate gyrus, bilateral insular lobes and left caudate nucleus were enhanced significantly (all P < 0.05, AlphaSim correction), suggesting that the structural and functional damage was found in multiple brain regions in patients with delirium. Conclusions:Multiple brain regions of patients with delirium present abnormal resting-state brain function. The abnormal resting-state brain function of the left superior frontal gyrus is closely related to the occurrence of delirium. Structural damage is found in multiple brain regions of patients with delirium. The structural changes in the frontal lobe, temporal lobe, corpus callosum, hippocampus and cerebellum and their abnormal functions can be used as preliminary imaging indexes for the diagnosis of delirium.

MRI findings of superficial siderosis of the central nervous system / 实用放射学杂志

Objective To study the MRI findings of superficial siderosis of the central nervous system(SSCNS)and to improve the understanding of SSCNS imaging features.Methods MRI images of 21 cases were retrospectively reviewed.MRI plain scan (T1WI,T2WI)and diffusion weighted imaging(DWI)were performed in all patients;T2* weighted angiography(SWAN)scan was performed in 8 patients.Results On T1WI of 21 cases,only 4 cases showed infratentorial superficial siderosis which appeared as linear hypointense signal in sulci cerebelli and around brainstem.On T2WI of 21 cases,18 cases presented with linear hypointense signal on cerebral surface.On DWI of 21 cases,20 cases showed linear hypointense signal on cerebral surface,and the other one case showing negative signal on DWI presented hypointense signal on SWAN.On SWAN of 8 cases,more lesions were found in more regions.Conclusion SSCNS has characteristic findings on MRI.SWAN is sensitive to superficial siderosis.MRI is a reliable method for the assessment of SSCNS.

The diagnostic value of combination of 3.0T MR and mammograms for breast benign and malignant lesion / 实用放射学杂志

Objective To investigate the diagnostic value of mammography,3.0T MR and the combination for benign and malignant breast lesions.Methods Sixty-one patients with breast lesion proved by postoperative pathology included 47 malignant cases and 14 benign cases.Imaging indexes were recorded and analyzed for all cases,including TIC type,ADC value and whether the Choline peak was detected on MRS.SPSS 17.0 statistical software package was used for analysis.Chisquare test was used for count data and P<0.05 was considered as statistically significant.Results The accuracy were 45.9% and 62.3% respectively for mammography or MR as a sole method for the diagnosis of benign and malignant breast disease.When combining the two techniques,the diagnostic accordance rate was 80.3%.The rate based on the combination of mammography and MR were higher than on basis of either kind of examination along, with a statistically significant difference (χ2=4.08,P<0.05).Conclusion MR examination was superior to mammography for the diagnosis value of benign and malignant breast lesions.When combining mammography with MR examination,it could not only obviously improve the accuracy of preoperative diagnosis of breast cancer but also provide the theoretical basis for the early diagnosis and the prognosis.