Date of Award
Master of Science in Biomedical Engineering - (M.S.)
Bryan J. Pfister
Yahia M. Al-Smadi
Near infrared (NIR) lasers have been used in medical applications both for diagnostic and therapeutic purposes. Temperature elevation profile inside the tissue is a critical factor that needs to be better understood in these applications. The purpose of this study is to determine the temperature distribution due to a low power N I R laser irradiation in living neural tissue. Temperature measurements were made directly using a thermocouple probe inside the rat brain cortex within the sagittal plane. The spatial map indicates that N I R light penetrates more readily in the vertical directions than the spreading in the horizontal axis. The decrease in the vertical direction can be approximated with a single order exponentially decaying function. The results also suggest that the temperature elevation can be kept below 0.5 °C anywhere in the tissue if the incident laser beam power density is less than 27 mW/cm2. These experiments should be repeated in other types of neural tissue such as the white matter of the brain and the spinal cord to obtain more complete results.
Ersen, Ali, "Temperature elevations due to NIR exposure in the brain tissue" (2011). Theses. 114.