Preoperative workflow for lymph nodes staging.

PURPOSE: Accurate staging of lymph nodes relies mainly on surgical exploration and manual palpation. We present a new non-invasive diagnostic approach: simulated palpation through virtual laparoscopic instruments.
METHODS: We set up a diagnostic process to extract lymph nodes shape and position from CTs and to analyze the trend of pixels intensities to determine tissue properties in order to feedback the force information.
RESULTS: We have integrated the model, obtained from both the morphological information and stiffness values, in our laparoscopy simulator and surgeons can virtually palpate, with a haptic device, the lymph nodes. We evaluated the workflow extracting lymph nodes from a case study: the feedback provided through the simulator greatly helps the surgeon in the correct staging.
CONCLUSIONS: Results show the feasibility of the approach and in the future we will clinically evaluate this new diagnostic methodology. We are studying the possibility to integrate CTs with other imaging systems to increase the accuracy.