Detection And Localization Of Neuronal Activity After Spinal Cord Injury Based On Near-infrared Spectroscopy

Traffic accidents,mechanical impacts,high-altitude fallings and other accidents may cause body's spinal cord injury(SCI),which leads to the interruption of body's neural signals' transmission channel,and will cause the function damages of partial limb.In today's medical conditions,the conventional instruments can't detect and locate the damaged nerve cells.So,doctors can not accurately diagnose the patients' specific situation,which will be likely to delay the disease and lead to the lifelong paralysis seriously.In recent years,the combination of near-infrared(NIR)spectroscopy and computer simulation has promoted the development of NIR spectroscopy for noninvasive detection of material methods.At the same time,because of the difference between the absorption and scattering of NIR light in the biological tissue,NIR light has a high discernment to soft tissue of variation.So,NIR spectroscopy can be used to get the optical parameters about the tissue and establish the relationship between tissue optical parameters and spectral data.Therefore,this paper presents a method for the detection and localization of neuronal activity after SCI by NIR spectroscopy.This paper mainly consists of three parts:Firstly,in order to apply the spectral data to the detection of neurons in SCI,remove the irrelevant information and noise contained in the spectrum.The Fourier de-noising and wavelet de-noising methods are compared in this paper.It's found that the method of wavelet de-noising has better effect on the de-noising of the original signal through the analysis of the simulation and performance parameters.And this paper has discussed the noise reduction of the original signal by the different orders of the wavelet function dbN.The results show that the wavelet packet db4 function has the best de-noising effect based on the simulation results and the comparison of the performance parameters.Secondly,a new method is proposed to detect the SCI neural cells.On the basis of animal experiment,the neuronal cells were classified by cluster analysis,and according to the partial least squares algorithm,the results of the classification were quantitatively analyzed then.If the concentration of each substance was reduced or close to zero and the difference of the concentration of the spinal cord before and after the spinal cord injury is negative,the nerve cells are dead.Thirdly,a method based on NIR spectroscopy to analyze the location of nerve cells in SCI is proposed.The Monte Carlo method is used to establish the three-dimensional model of human spinal cord,which can simulate the transmission of photons and calculate the attenuation coefficient of NIR light in human tissue.Thus,the nerve cell location can be analyzed according to the attenuation coefficient generated by the two-dimensional distribution of SCI.In this paper,NIR spectroscopy based on the analysis of SCI nerve cell activity detection and location for clinical medicine provides a noninvasive nerve cells method which can make up for the current lack of medical testing methods.In addition,this method can also be applied to the detection and analysis of cancer cells,which will contribute to the diagnosis of some cancers in the future.