Sodium Alginate Ultrasound Phantom for Medical Education

The ultrasound phantoms used to educate medical students should not only closely mimic the ultrasound characteristics of human soft tissues but also be inexpensive and easy to manufacture. I have been studying handmade ultrasound phantoms and proposed an ultrasound phantom comprising calcium alginate hydrogel that met these requirements but caused a speckle pattern similar to that observed in ultrasound images of liver. In this study, I show that adding ethanol to the precursors used to fabricate the phantom reduces the speckle pattern. The ultrasound propagation velocity and attenuation coefficient of the phantom were 1561 ± 8 m/s and 0.54 ± 0.18 dB/cm/MHz, respectively (mean ± standard deviation), which are within the ranges of those in human soft tissues (1530-1600 m/s and 0.3-1.0 dB/cm/MHz, respectively). This phantom is easy to fabricate without special equipment, is inexpensive, and is suitable for elementary training on ultrasound diagnosis, operation of ultrasound-guided needles, and blind catheter insertion.

An Affordable and Easily Recreated Ultrasound Phantom for DVT

Evaluating a patient for a deep vein thrombosis (DVT) using ultrasound is a common procedure in the emergency department. Teaching a clinician to identify a DVT on ultrasound is often done on a phantom, which is a synthetic model intended to simulate a clinical condition. Traditional commercial ultrasound phantoms modeling a DVT exist, but can be prohibitively expensive. We have created a DVT phantom by embedding a water-filled balloon containing a smaller balloon filled with water and an acrylic polymer in a gelatin-psyllium hydrophilic mucilloid fiber mixture. This phantom is durable, easily created, and affordable. It provides clinicians the ability to learn to identify a DVT on a phantom prior to performing the procedure on a patient.

Non-animal ultrasound phantoms for device testing and training

A phantom is a physical object to simplify device testing and clinical training. An industrial device is more reliable for device testing in quality control procedures, though it is expensive. When precision requirements are not so strict as it occurs in training, people prefer to use home-made phantoms, though many of these artisanal methods use animal products. The current paper illustrates a few alternative vegetal phantoms. Agar is a widely used material in laboratory investigations and can be used to contain ultrasound targets. Another quick and effective alternative is given by tofu. Target sizes and flow ultrasound measurements can be easily effected using a phantom and training can be planned and repeated as much as required. The current paper shows how low-cost animal phantoms can be perfectly replaced by low-cost vegetal ones for clinical and training purposes. Vegetal phantoms can be classified as possible realizations of the Replace, the 1st of the 3Rs pre-requisites for non-animal experiments.