Tissue oxygen saturation (StO2) is the average blood oxygen saturation in a given section of tissue. It is an important measure of tissue health and thus an important parameter in many clinical situations (e.g. tissue viability monitoring, cancer treatment, ...). As tissues consume oxygen to produce energy, haemoglobin in the local capillary blood supply is stimulated to release its bound oxygen. Thus, the percentage of oxy-haemoglobin in a volume of tissue (StO2) is an indicator of tissue oxygen consumption and, ultimately, tissue health.

A pulse oximeter measures arterial oxygen saturation (SaO2). However, it does not necessarily relate to local tissue health. A person with excellent arterial oxygen supply could have a region of poorly perfused tissue that becomes necrotic.

We have used different optical techniques to study tissue oxygenation in healthy volunteers. We will now further study and develop tissue oximetry technology to gain real-time readings of StO2 in localized volumes of tissue. With these capabilities, surgeons and other clinicians can detect medical problems sooner, improve outcomes for patients, and reduce costs.