The Research Of Different Acupunacture Methods On Cerebral Cortex In Vivo Monitored By Photoacoustic Tomography

In the less than 20 years of entering the new century,both Chinese medicine and Western medicine have made great progress.As a traditional Chinese medicine inheritance,modern Chinese medicine has become more and more important in the modern medical field.As a representative of empirical medicine,Chinese medicine has been consistently recognized for its clinical diagnosis and treatment effects for thousands of years.However,the scientific community has no general consensus on its deep principles of the role of the body.Acupuncture is a sub-area of traditional Chinese medicine.This study aims to reveal the mechanism of acupuncture by exploring the changes in hemodynamics induced by acupuncture.At present,the mainstream imaging methods of brain imaging include Electroencephalography(EEG),Computed Tomography(CT),Magnetic Resonance Imaging(MRI),and Positron Emission Tomography(PET).Each imaging method has its own limitations.This study uses the emerging Photoacoustic Tomography(PAT)as a tool to monitor the effects of acupuncture on cerebral hemodynamics.PAT illuminates biological tissue with a pulsed laser that excites the generation of ultrasound,which combines the high contrast of various biomolecules in optical imaging and the high resolution achieved by acoustic imaging for biological tissue penetration.In this study,in order to reveal the mechanism of acupuncture by observing the relative changes of cerebral cortex hemodynamics,different acupuncture points and acupuncture manipulation methods were used to explore the results of brain imaging by photoacoustic tomography during and after acupuncture.The main work includes:1.Introduced the principle and the system of photoacoustic imaging.Based on the theoretical basis of the photoacoustic effect,deriving the photoacoustic wave equation from Newton’s law of motion,continuity equation and thermoelastic equation.Then we discuss three kinds of image reconstruction methods: back projection,delay and sum algorithm and finite element reconstruction algorithm.Based on the theoretical discussion,the photoacoustic tomography system used in this research is introduced in detail,including various parts of the hardware system and various modules of the software system.2.Investigate the effects on hemodynamics in mouse cerebral cortex induced by different acupoint stimulation.Firstly,the differences between Zusanli and Yongquan were discussed from the perspective of traditional Chinese medicine.Secondly,various aspects of the experimental design were elaborated.Finally,the two groups of experiments were compared with the imaging results and statistics.3.Investigate the effects of hemodynamics in mouse on cerebral cortex induced by different acupuncture methods.Firstly,the three acupuncture methods were be introduced in detail,and were be compared in the term of operating parameters and basic mechanisms.Then,the design of experiments on the effects of different acupuncture methods on the hemodynamics of the cortex is discussed in detail.Finally,the detailed description of the experimental results and the statistical analysis and demonstration are carried out.This study has fully confirmed the application prospect of photoacoustic tomography in the field of brain imaging.By investigating the effects of electroacupuncture on cerebral cortex hemodynamics at different acupoints,it was found that different acupoints had different effects on cerebral hemodynamics,and the increase of blood flow in Zusanli was more obvious and holding until the end of the observation.However,the blood flow in Yongquan was gradually returned to the initial level after the stimulation was completed.By exploring the effects of hemodynamics in mouse on cerebral cortex induced by different acupuncture methods,it was found that three acupuncture methods have different effects on cerebral hemodynamics.The stimulating response curves of manual acupuncture and moxibustion appear as rising and holding until the end.The response curve of electroacupuncture showed rise and then fall.Electroacupuncture and moxibustion have specific influence to different regions of the brain,and the manual acupuncture has a promoting effect except for the right auditory region.The conclusions of the three acupuncture methods further confirmed the effects of serotonin,dopamine and adrenaline in the central nervous system on the hemodynamics of the cerebral cortex.