Ex Vivo Evaluation of a Soft Optical Blood Sensor for Colonoscopy

Colonoscopies are vital procedures allowing diagnosis of colorectal cancer and other gastrointestinal diseases. However, excessive forces may be applied to the colon during navigation. This can cause bleeding, especially in patients presenting inflammatory bowel diseases. The endoscopist is often unable to detect bleeding as visualization is limited to the distal tip camera of the endoscope. Thus, there is a need to have bleeding detection capabilities behind the device tip. This work presents a soft optical blood sensor that can be mounted onto a colonoscope. The presence of blood in the sensor's microchannel causes a reduction in optical transmission, and the endoscopist is alerted. We evaluate the sensor safety and performance ex vivo with a cohort of 10 endoscopists (novices and experts). We demonstrate the ability of the sensor to rapidly identify bleeding and easily integrate into the clinical workflow, without significantly affecting navigation time and the users' learning curve.