Functional Near-Infrared Spectroscopy using Catheters Closer to the Brain
Currently, two major tools in the field of functional brain imaging are functional Magnetic Resonance Imaging(fMRI) and functional near infrared spectroscopy (fNIRS). Compared with fMRI, fNIRS is much cost effective and can be applied to a wider range of subjects including infants. However, one big disadvantage of fNIRS is its penetration depth into the brain due to the blockage of the scalp and skull.
To solve this problem, we are developing a fNIRS fiber optical catheter that can be inserted into human nasal cavity and ear canal so that the skull can be bypassed. By this means, we can put the light source closer to the brain tissue. Also, by using a fiber optics probe, we will be able to couple different light source in (such as a supercontinuum laser) to the fNIRS system, thus potentially enabling us to acquire more information from the brain compared with conventional fNIRS with discrete laser diodes (typically 690nm and 830nm) as light source.