Fibre Optic Interrogated Palpation Sensor for Mechanical Tissue Assessment in Minimally Invasive Surgery

The advantages robotic assisted surgery offers compared with conventional laparoscopic surgery has led to increased use in recent years. However, a limiting factor is the lack of physical feedback information for the surgeon. For example, a characteristic marker for cancer location is the stiffness of the soft tissue. Typically, cancerous tissue has a higher stiffness than the surrounding healthy tissue. In this paper, we propose a design for an optical fibre interrogated palpation probe that can be used within minimally invasive robotic assisted surgery. The probe measures the force and displacement applied to the tissue via a flexible membrane. Initial tests have been carried out to measure the stiffness of silicone phantoms. In future, this can be expanded to more complex phantoms with stiff inclusions, and ex-vivo tissue samples.