Development of high fidelity liver and kidney phantom organs for use with robotic surgical systems

The development of high fidelity, anthropomorphically shaped physical phantom organs has a great potential to benefit novel robotic surgical systems by acting as a pre-clinical test bed to validate robotic performance. We present a manufacturing process and methodology to create inexpensive, anatomically accurate kidney and liver phantom organs from gelatin gel with Young's moduli and ultrasound (US) attenuation coefficients matched to those of a porcine kidney and liver. The ration of gelatin to water was varied in order to produce eight gelatin gel samples with a Young's modulus ranging from 8.88 kPa to 76.84. Fresh porcine liver and kidney organs were tested ex vivo to determine their Young's moduli and US attenuation coefficients. A 3D printer created an anthropomorphically accurate kidney mold based on x-ray computed tomography images of a human abdomen. The difference between the porcine and gelatin phantom Young's modulus was less than 2.1 kPa for both the kidney and liver. The US attenuation differed at most by 0.577 dB(cm·MHz)-1 when comparing the phantom material to the porcine organs. The volume of anthropomorphically shaped gelatin phantom kidney was within 5% of the volume of the virtual kidney organ which was constructed from x-ray computed tomography. With a total material cost of approximately $0.70 per organ we foresee these organs to be used in a disposable fashion to facilitate the development of novel surgical robotic systems.