Smart Artificial Soft Tissue - Application to a Hybrid Simulator for Training of Laryngeal Pacemaker Implantation

Abstract

Surgical simulators are safe and evolving educational tools for developing surgical skills. In particular, virtual and hybrid simulators are preferred due to their detailedness, customization and evaluation capabilities. To accelerate the revolution of a novel class of hybrid simulators, a Smart Artificial Soft Tissue is presented here, that determines the relative position of conductive surgical instruments in artificial soft tissue by inverse resistance mappings without the need for a fixed reference point. This is particularly beneficial for highly deformable structures when specific target regions need to be reached or avoided. The carbon-black-silicone composite used can be shaped almost arbitrarily and its elasticity can be tuned by modifying the silicone base material. Thus, objective positional feedback for haptically correct artificial soft tissue can be ensured. This is demonstrated by the development of a Manuscript received 24 February 2022; revised 27 July 2022; accepted 21 August 2022. Date of publication xxx; date of current version xxx. The financial support of the Austrian Research Promotion Agency (FFG) under project grant number 845436 and the company MED-EL Elektromedizinische Ger äte Gesellschaft m.b.H., Innsbruck, Austria, is greatly acknowledged.

Open Source Sensor Interface for Soft Detectors in Surgical Simulators

“…By combining two such surfaces [11], position detection in independent directions can be realized (1.5D, Figure 1b). Further refinement is the realization of two-dimensional (2D) position detection within one layer (Figure 1c) [7], [12] based on resistivity measurements or electric field distributions. By combining multiple 2D sensor layers, resolution in the third spatial dimension (2.5D) can be achieved (Figure 1d).…”

“…Functionalities specifically for surgical simulators (as specified in Chapter II-A) were also integrated to allow the detection of conductive insertion tools. Because the contact points of electrodes to the soft sensor material (carbon-black-silicone composites) often exhibit considerable contact resistances [7] owing to impurities, boundary, or oxide layers, details of capacitive incoupling of signals were taken into account [22]. These and further subtleties regarding the improvement of the signal-to-noise ratio (SNR) [23] were considered in the circuit design.…”

“…Some examples of applications were tested to demonstrate the applicability of SIC. The sensor material used was a carbon black-silicone composite based on Ecoflex 35 Fast (Smooth-On, Inc., Macungie, PA, USA) with 7.5 wt% carbon black (XPB 545 POWDER from ORION Engineered Carbons GmbH, Frankfurt, Germany), whose exact composition and preparation were described by Thurner et al [7].…”

“…Therefore, the class of hybrid simulators extends virtual simulators by including haptic feedback [5], [6], which is achieved through a sophisticated linking of physical and virtual simulator components. This ensures comprehensive learning success, and sometimes even original surgical instruments can be used [7].…”

“…To avoid expensive electromagnetic [5] and optical [8] tracking systems in surgical simulators, soft sensors inside physical patient phantoms are cost-efficient and sophisticated alternatives. They allow relative position detection in soft and deformable synthetic tissue imitations [7] to evaluate the manipulation of flexible target areas. Haptics are not distorted by such soft sensors and real surgical instruments can be used to optimally train motor skills related to instrument handling.…”