A 3D-Printed Tactile Sensor Based on Fiber Bragg Grating Sensors for Lymphadenopathy Detection

Lymphadenopathy represents an alteration in the size or character of the lymph nodes, associated with different conditions, like inflammations, autoimmune diseases, and malignancies (e.g., lymphomas). To date, the lymphadenopathy detection relies primarily on palpation examinations, that consist of applying variable forces on the tissue to identify alterations in size, mobility, and tenderness of the lymph nodes. However, this practice carries substantial risk of misdiagnosis, since it is strongly affected by the experience and attention of the examiner. To overcome the limitations of tissue palpation, tactile probes based on different sensors were proposed to support the identification of abnormalities in soft tissue. However, so far, no studies explored the application of tactile sensing technologies for the palpation of lymph nodes. The aim of this study is to propose the use of a 3D-printed tactile sensor based on fiber Bragg grating (FBG) technology for lymph node palpation and lymphadenopathy detection. In particular, this work focused on cervical lymph nodes. To mimic a frequently diagnosed pathology (i.e., lymphadenopathy of cervical lymph nodes), we manufactured two phantoms of cervical neck tissue with physiological and pathological lymph nodes. Palpation tests under controlled conditions were performed to assess the feasibility of the proposed sensor to discriminate the presence of lymphadenopathy. The encouraging findings will foster further optimization of the tactile sensing system for improving the early diagnosis of lymphadenopathy and supporting clinical practice.