Towards tactile sensation in laparoscopic surgery

Kurzfassung

Hepatic tumorous lumps appear as stiff inclusions within the surrounding soft, healthy tissue. In open surgery they are searched for through manual palpation with the gloved fingertip. However, to exploit the benefits of minimally invasive laparoscopic surgery including less pain for the patient as well as a shorter hospital stay, i.e. a decrease of costs, it is mandatory to implement a substitution for the human sense of touch. Therefore, a tactile instrument has been conceptualized, elaborated and tested within the course of this thesis. The main goal was to enlarge the sensing area at the tool tip once it has entered the abdominal cavity through the restricted diameter of the trocar. The provision of a large sensitive surface enables the detection of nearly all sizes of tumors and decreases the time needed for task performance. The focus of this thesis was the development of a suitable mechanical structure for the tactile tool serving as a carrier for an existing flexible silicone sensor. Two different constructions have been selected from a number of concepts and manufactured as prototypes by laser sintering in polyamide. Consequently, on the base of the results acquired from automated and manual subject palpation tests on artificial silicone and porcine liver samples it has been evaluated that a prototypical instrument with a laterally opening lid would be a suitable device for intraoperative tumor detection in laparoscopic liver surgery.