Eyes of the needle: Spectral tissue sensing, an innovative technology for detecting various tissue types during percutaneous needle-based procedures in locoregional anesthesia and pain medicine

This dissertation studies the possibility of differentiating various tissue types from each other by using light. Local anaesthetics or pain medicines are administered by inserting a needle into a nerve region. During this procedure, it is important to differentiate various tissue types from each other, such as fat, blood, muscles and nerves, in order to avoid complications. In this study, a special needle was developed with the ability to emit light and measure how this is reflected (a method called spectral tissue sensing or STS). Different tissue types may have different absorption and light reflection patterns. By making measurements and developing an algorithm, tissues can be differentiated from each other based on these data. By using STS during procedures in pain medicine, the needle can be inserted more safely and more accurately. STS allows the tip of a needle to serve as the eye of the doctor.