Investigation Of Neural Recovery Mechanisms Of Brain Functional And White Matter Abnormalities Induced By Bariatric Surgery In Obese Patients

With the rapid growth of the economy in China, people's living standards have markedly improved over the past decade, meanwhile the pace of our life is becoming faster and faster and the pressure is increasing. Our economy is catching up to the Western countries with the speed of light, but at the same time, unhealthy food in United States and Europe is also flowing onto the Chinese people's dinner tables. The change in diet structure coupled with the surging social pressure and ignoring basic training has led to more and more obese patients in China. Obesity causes many chronic diseases such as hypertension, high cholesterol and cardiovascular disease; in addition to obesity, this can also cause mental disorders, and even delays the pace of development of society and the economy. Nowadays, many countries are trying their best to look for obesity treatment methods and research solutions, such as exercise, acupuncture, diet, and even diet pills. Among the many weight loss methods, bariatric surgery can help lose weight quickly and maintain weight over a long period of time. However, the links between bariatric surgery and the change in brain function and structure is unclear.We selected obese patients and normal subjects, followed up obese patients, and collected normal and patients' functional magnetic resonance imaging(f MRI) and diffusion tensor imaging(DTI). We extracted the power spectrum of low-frequency in different brain regions using the Amplitude of Frequency Fluctuations method, and then picked out the regions of interest between brain areas with differences(hippocampus, thalamus, Insula, Nac, putamen, Orbifrontal Cortex(OFC), Anterior Cingulate Cortex(ACC)). We analyzed the causal connections between these brain regions using the Granger causality analysis method. By comparing these connections, the abnormal changes in the Ventromedial Prefrontal Cortex(VMPFC) and Orbifrontal Cortex(OFC) decreased and(Dorsal Lateral Prefrontal Cortex) DLPFC's inhibition action increased after bariatric surgery. A majority of activated brain areas and causal connections was mainly distributed in the Frontal-Mesolimbic areas, the striatal areas and frontal cortex of the brain. By comparing the white matter fibers in the three groups, obese patients' white matter fibers had damage in the main fibers, such as in the(Cingulate Cortex) CC, Superior Longitudinal Fasciculus(SLF) and Fornix(cres) / Stria Terminalis(FX/ST) and so on. These white matter lesions represented the repair after one month following bariatric surgery. We also explored whether the activating functional regions had structural connections by the fiber tracking method. A preliminary study found that some of the majority of the fibers presented in the resting state networks managed the control reward, movement, and visual brain circuits.We can understand obesity better by researching the brain and the multimode networks. We provided clinical imaging data and references for the early prediction and for controlling obesity.