What is Transdermal Optical Imaging (TOI)?

FaceScan uses Transdermal Optical Imaging (TOI) to capture health data from a user's face.

Transdermal Optical Imaging (TOI) uses a digital camera to estimate vital signs by analyzing the way light travels through the skin and is re-emitted to extract information about blood flow, the blood vessels, and other structures beneath the surface of the skin. FaceScan employs TOI to surface basic health vitals.

The process begins by using ambient light, which penetrates the skin and reaches the tissue below. Some of this light is re-emitted and captured by a camera. The color of that light contains information about both the blood and the skin2. The information is separated based on the different colors of hemoglobin (in the red blood cells in the blood) and melanin (in the skin) using advanced machine learning algorithms. These algorithms process the information to create a map of the blood flow across relevant areas of the face, which is then linked together to form a video of the changes in blood flow over time. Utilizing this blood flow map, various vital signs can be estimated.

Blood pressure is the measured force that blood exerts against the walls of the arteries as it flows through them. As the heart pumps blood, the blood vessels in the face will expand and contract. TOI can measure blood pressure by analyzing how much the shape of the blood vessel changes with each expansion and contraction, estimating blood pressure.

The heart rate is the number of times the heart beats per minute. This beating of the heart causes changes in the diameter of blood vessels. By measuring the rate at which these blood vessels change diameter, the heart rate can be estimated.

TOI can also measure oxygen saturation. Oxygen saturation is the amount of oxygen in the red blood cells in the blood. The more oxygen in the blood, the more hemoglobin is saturated with oxygen. TOI can measure the concentration of hemoglobin in the blood through the unique way it absorbs certain colors light, which can give then be used to calculate an estimate of the oxygen saturation of the blood.

TOI is often used as a non-invasive alternative to arterial blood gas analysis (ABG) where invasive methods are not practical or desirable. By analyzing these changes, the data signals captured by TOI are then passed through patented and proprietary calculations and algorithms to estimate health vitals.

Further information regarding TOI research can be found here:  https://bit.ly/2zbDgFk