How it Works
SnapshotNIR uses light in the near-infrared (NIR) spectrum that, harmlessly, passes through the skin and is reflected off the blood supplying the tissue to determine tissue oxygen saturation, a key indicator of tissue health. The NIR light has two key features that make it useful for measuring the viability of living tissue. Firstly, NIR light is not absorbed by tissue as much as visible or ultraviolet light. Secondly, NIR light is mainly absorbed by hemoglobin and water. Most importantly, the wavelength dependent light absorption of hemoglobin differs if it is carrying oxygen from when it is not. This makes NIR light very useful in detecting oxygenated and deoxygenated blood, which conveys a comprehensive picture of tissue health and the healing capacity of wounds or tissue transplants.
The video below shows a forearm cuff study in which the Kent Imaging device system was used to capture oxygenation images before ischemia, during ischemia and post ischemia. The video is a compilation of images taken by the Kent Imaging device every 8 seconds during the application and then release of a blood pressure cuff. In the images red indicates a higher oxygenation level, while blue indicates a lower oxygenation level.