The oxygenation level of a tissue is an important marker of the health of the tissue. Sustained extreme oxygenation levels, in either direction, can cause irreparable damage. In stroke survivors, it has been shown that the blood flow to paretic limbs is significantly reduced compared to a non-paretic limb. We hypothesize that hemodynamic activity in stroke affected muscles is suppressed as compared to normal muscles.A clear understanding of the way stroke-affected limbs respond to rehabilitation exercises and a convenient method for monitoring this progress will allow clinicians and therapists to tailor treatments based on individual response.
In order to measure the hemodynamic activity, we developed a prototype optical sensor to measure the relative changes in the concentration of oxygenated and reduced hemoglobin (Hb and HbO2) in the tissue using Beer’s Law: