System characterization for a fast optical imager

Abstract

In contrast to morphological imaging, functional imaging captures information about the functioning for living tissues, such as blood circulation and oxygen metabolism, cerebral nervous system, and changes in cromophore concentration. In recent years, progress in PET and MRI technologies has made these measurements possible. However both these systems are large and expensive and they have some limitations such as not being approved for use with infants in non-clinical settings and law temporal resolution. Optical imaging fills this gap by being completely non-invasive, portable, unobtrusive, law-east, and robust to motion artifacts. This M.Sc. thesis is involved with the development and modifications of a prototype fast optical imaging (FOI) system based on the functional near infrared spectroscopy system of University of Pennsylvania. FOI is designed by using inexpensive photodiode (PD) detectors and LEDs working in the near infrared spectrum. In addition to this a new probe design considering limitations of the preceding versions is also completed. The aim of the work was to develop a simple and robust instrument and probe to monitor brain activity, during cognitive task. The ability and effectiveness of the system is tested by several experiments based on phantom studies. Preliminary results are promising to continue on human subjects.|Keywords :FOI, functional near infrared spectroscopy(fNIR), brain imaging, optical imaging, neuroimaging.