Speaker
Description
Introduction
3D-printed physical organ models have revolutionised the surgical field with applications in training, planning, rehearsal, and patient education[1]. Recent advancements in digital health technologies, such as the introduction of digital twins (DT) in medicine, present further opportunities where these models could play an important role. By developing a mechanically-realistic, anatomically-accurate, and patient-specific physical organ model, a DT framework may be designed to assist surgeons throughout the entire perioperative process[2]. To achieve this, the first step is to develop a 3D-printed model based on human imaging data composed of materials that closely mimic the mechanical behaviour, including elastic and viscoelastic properties. and the tactile properties of human soft tissue. In this work, we developed an interpenetrating polymer network (IPN) hydrogel with tunable mechanical properties produced via light-based 3D-printing for the fabrication of surgical kidney models.
Methods
The resin comprised a synthetic photopolymer (NP; 0.5 M, 1 M), crosslinker (25 mM, 50 mM), photoinitiator (0.2% (w/v)), photoblocker (0.02% (w/v)), and sodium alginate (1% (w/v), 2% (w/v)) in deionised water. Following 3D-printing (LumenX+, CELLINK), the structures were immersed in barium chloride (BaCl2; 66 mM). Mechanical characterisation was carried out via (i) uniaxial compression tests at a rate of 5%/s (Mach-1, BioMomentum, Inc.) and (ii) rheological frequency sweeps from 0.1 Hz to 10 Hz at a fixed shear strain of 0.01% (Kinexus Pro+, NETZCH), to investigate elastic and viscoelastic behaviour, respectively.
Results and Discussion
By varying monomer concentrations, the mechanical properties of the IPN hydrogels could be fine-tuned (Fig.1a-d, f), with some formulations revealing comparable behaviour to both human and porcine kidney tissue reported in the literature [3-5]. Using these hydrogels, scaled-down 3D-printed models of human kidneys were produced as a preliminary step towards fabricating surgical kidney phantoms (Fig.1e).
Ongoing work involves 3D-printing optimisation of the kidney models and surgical tool-tissue interaction deformation studies using an RGB-D camera to feed data to a DT. Overall, this approach shows great promise in producing mechanically-realistic organ phantoms, potentially reducing dependency on cadavers and animals in surgery, while also contributing to the development of cutting-edge digital health technologies, such as the proposed real-time Digital Twin-Assisted Surgery (DTAS)[2].
Acknowledgements
The authors acknowledge financial support from the UK Research and Innovation (UKRI) Engineering and Physical Sciences Research Council (EPSRC, EP/X033686/1), and the Animal Free Research UK and RSPCA UK for the monetary prize awarded at BioMedEng 2025
[1] Qiu, K., et al., 2018, Annual Review of Analytical Chemistry. 11(2018): p. 287-306.
[2] Asciak, L., et al., 2025, npj Digital Medicine. 8(1): p. 32.
[3] Karimi, A. et al., 2017, Irbm. 38(5): p. 292-297.
[4] Snedeker, J.G., et al., 2005, Journal of biomechanics, 2005. 38(5): p. 1011-1021.
[5] Nieva-Esteve, G., et al., 2024, Materials Advances. 5(9): p. 3706-3720.
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