SonoGuar: A Self-healing Hydrogel for Higher Fidelity Ultrasound-guided Procedure Training

Area of Science:

• Biomaterials Science
• Medical Simulation
• Surgical Training Technologies

Background:

• Commercial ultrasound-compatible procedural phantoms for vascular access training are expensive and lack durability.
• Existing low-cost alternatives often fail to provide adequate fidelity and realism.
• There is a need for cost-effective, durable, and high-fidelity training models.

Purpose of the Study:

• To synthesize and characterize a novel, self-healing, ultrasound-compatible hydrogel (SonoGuar) for vascular access training.
• To evaluate the rheological properties, ultrasound imaging fidelity, and user experience of SonoGuar compared to a commercial model.
• To assess the cost-effectiveness and performance of SonoGuar in a simulated training environment.

Main Methods:

• SonoGuar was synthesized using guar gum, borax, glycerol, oil, and water.
• Rheological analysis assessed viscoelastic recovery after simulated injury.
• Blinded ultrasound image and randomized simulation studies compared SonoGuar to a commercial model with 41 participants.

Main Results:

• SonoGuar fabrication cost ~$3/kg, significantly lower than the commercial model's $350 insert.
• The hydrogel demonstrated self-healing properties, recovering viscoelasticity within 30 minutes and healing needle tracts within 5 hours.
• SonoGuar was rated 1.8 times more likely to resemble human tissue and received higher user preference scores for realism and tactile feedback from experienced clinicians.

Conclusions:

• SonoGuar is a rapidly fabricated, high-fidelity, self-healing hydrogel suitable for durable and scalable ultrasound-guided procedure training.
• The low-cost SonoGuar outperformed a leading commercial model in imaging realism and user preference among experienced clinicians.
• This DIY hydrogel offers a promising, cost-effective solution for enhancing vascular access training.