Changes Of Hippocampus Volume And Magnetic Resonance Spectrum In Type2Diabetes Patients

BackgroundMild cognitive impairment (MCI) was the early state of Alzheimer’s disease progress with an annual conversion rate from6%to25%. MCI was characterized by the memory loss and cognitive dysfunction that exceeded the normal scale adjusted for aging. With the continuous improvement of living standards, an aging population and changes of the lifestyle, the number of patients with type2diabetes increased rapidly, reaching up to9.7%. Type2diabetes was an independent risk factor for progress from mild cognitive impairment to AD. Patients with type2diabetes demonstrated risk to develop AD three times higher than healthy subjects. The influence of cognitive impairment mainly reflected in learning, memory decline, and so on. Therefore, type2diabetes patients with early cognitive impairment were gaining more recognition as high risk population for AD, of which the investigation would help to improve early diagnosis and treatment of Alzheimer’s disease and delay its onset and development.ObjectivesBased on the analysis and MoCA rating scale from diabetes patients and healthy people, the research subjects were selected. Hippocampal size and biochemical parameters were compared using magnetic resonance imaging (MRI) and magnetic resonance spectrum (MRS) analysis to explore the potential clinical relevance in early diagnosis of type2diabetes with cognitive dysfunction, providing a theoretical basis for early diagnosis and treatment. Methods1. Using Montreal cognitive assessment scale to evaluate whether there was cognitive dysfunction.2. Employing the Siemens3.0T magnetic resonance to scan the hippocampus of the subjects. Acquired images were subsequently processed for a3D stereoscopic reconstruction.3. After the outlining of the hippocampus based on3D images, absolute volume of the hippocampus was calculated. Meanwhile we performed the standardized processing to obtain the relative volume of the hippocampus.4. Using the multiple vowels to collect the data of the1H-MRS, MRS peaks and the wave areas under the curve of the NAA、Cho、Cr and MI had been obtained as well as the ratio of the NAA/Cr, MI/Cr and Cho/Cr. All these data were statistically processed.5. Statistical comparison of the volume of the hippocampus and MRS date by SPSS13.0.Results1. There were no statistical differences on the ages, sex, the education, height and blood pressure between the T2DM group and normal control group of diabetes. But in terms of body weight, body mass index, fasting blood glucose and glycosylated hemoglobin, the T2DM group was significantly higher than that of normal control group.2. All45subjects were administrated magnetic resonance imaging. The spatial markers of hippocampus could be visualized clearly on MRI image. And the working station could show the3D images on transaction, coronal and sagittal sections. In the MRS image, we acquired steady ratio of NAA/Cr、MI/Cr、Cho/Cr.3. The hippocampus volume between type2diabetes of group and healthy subjects was compared, and bilateral hippocampi volume of T2DM group was significantly reduced.4. Type2diabetes showed significantly decreased NAA/Cr and increased MI/Cr in comparison to healthy subjects, whereas Cho/Cr remained comparable between these two groups.Conclusions1. MRI and MRS technique were capable of generating clear hippocampus images and stable spectrum images to facilitate clear visualization of sectional hippocampi markers.2. The hippocampus volume of T2DM group demonstrated significant atrophy compared with normal group. In addition, the results of magnetic resonance imaging (MRI) and magnetic resonance spectrum (MRS) analysis demonstreted that the neuronal marker NAA decreased, while the glial cell marker MI increased in T2DM. Cho, which involved in composition and decomposition of cell membrane phospholipid, kept unchanged between T2DM and healthy subjects.