CREATION OF AN INTERVENTIONAL NECK ULTRASOUND PHANTOM
By Vikesh Chandaria, St George’s University Hospital NHS Trust
To date, there is a lack of readily available and economical training phantoms for interventional applications. Our aim was to produce a simple, cheap and reproduceable neck phantom with anatomical features important for ultrasound guided procedures.
Our specification was to produce a curved sonolucent phantom with both carotid arteries, internal jugular veins, trachea and thyroid gland from a tissue mimicking material (TMM) (Figure 1). The phantom would also include multiple cyst-like lesions for users to target during training.
Liquid TMM was poured into 3D printed custom molds designed in an online computer aided design (CAD) platform. The dimensions of the neck and internal features were estimated and based on average sizes documented online. A consultant head and neck surgeon verified that the proportion and size of the anatomical features was representative of normal anatomy (Figure 2).
Five phantoms were made in total. Four phantoms were used during an interventional ultrasound surgical training day where they received great feedback. They were able to withstand multiple users (>10) imaging the phantom and multiple needle punctures without cracking or buckling. The fifth phantom was only used for imaging purposes without any interventions. Expert radiologists and surgeons were impressed with the similarity in appearance and contrast of the thyroid compared to background tissue (Figure 3). The cysts included in the phantom were identifiable and able to be targeted by trainees (Figure 4).
We have produced an anatomical and cheap training phantom with fluid filled targets. The advantage of these phantoms over commercially available ones is primarily the cost, however, they also have the advantage of being customisable and reproduceable should they be damaged. The use of CAD and a 3D printer made it possible to create realistic anatomical geometries. Further work is needed to increase the robustness and lifespan of the phantom material.