Research On Functional Brain Near-Infrared Imaging

With the development of science and technology, today's science has the prominent property of multidisciplinary intercrossing and fusion. The research content of medical imaging includes computer science, medical biotechnology, and physical chemistry , et al. It is one of the fastest developing domains in medical technology since 1980's. By using of these imaging methods, we entered a new digital medical era. Since the assistance of computer technology in diagnosis and examination, the way of traditional diagnosing has been changed and the diagnostic accuracy and effectiveness has been also improved greatly.Medical image technology develops rapidly in recent 20 years. Finding new imaging technique and improving the resolution of the images have always been a hot topic and application in medical imaging. Every new computing technique and new computing method has had a great and profound effect on medical research and medicine development. Near-infrared spectroscopy(NIRS)has been widely used ,because it is noninvasive, has better temporal resolution and lower instrumental cost, comparing to other imaging methods.Brain is the never center of human being and controls all the activity of the body. People are puzzled by the connections between brain structure and function. Since the complexity of the brain structure and brain function, it is very difficulty to find an imaging method of brain function with better temporal resolution and depth resolution. Brain activations usually accompanied with changes in concentrations of hemoglobins, which are major absorber of near-infrared light in brain tissues, so near-infrared light can be used to detect brain activations. NIRS can be used for long time monitoring with simple and cost-effective instrument. It is an ideal method of brain imaging and has a big application prospect.The paper introduces the successful application and progress of computer image processing technology, which has been used in medical research. We discuss the principle of existent human brain imaging technology such as CT, fMRI, PET and so on. With the comparison we can learn more about imaging study of human brain function. Then, we discuss what is known about the physical and physiological basis of NIRS in detail. Special attention is paid to the image reconstruction algorithm. An improved algorithm is proposed and realized a finger-tapping experiment, which can enlarge the imaging region and improve the depth resolution. Then, experimental results are given, which illustrates the correctness and efficiency of this algorithm.Another important field NIRS can be used in is breast imaging. In breast imaging, NIRS can detect smaller and earlier tumor. This will benefit its clinical application. Last, the work in future and prospect of the technology are presented.