Date of this Version
Beyersdorf, Conner J. Circle of Willis Functional Model for Transcranial Doppler Ultrasound Training. University of Nebraska-Lincoln. 2018.
Transcranial Doppler (TCD) ultrasound has proven to be effective in monitoring blood flow in the Circle of Willis in the brain. However, it requires significant practice on living patients and experience to accurately perform and interpret TCD. The rapid prototyping of a model able to mimic physiologic blood flow as seen in the Circle of Willis could alleviate deficiencies in TCD application and serve as an educational tool to medical students and professionals in diagnosing blood flow abnormalities such as stenoses or emboli. Two experiments were carried out to measure the physiologic and pathologic blood flow capabilities of a Circle of Willis model. The model was designed in a computer software and 3D-printed in a flexible material known as Tango Plus. The model was set inside of a gelatin phantom in a plastic skull to simulate the brain with correct anatomical positioning. A mixture of water and dehydrated milk were pumped through the model by a peristaltic or pulsatile pump, while TCD readings of phantom blood flow in the anterior cerebral arteries and internal carotid bifurcation were collected. The model accurately represents the Circle of Willis with comparable flow patterns to both physiologic and pathologic blood flow, demonstrating its utility as a functional teaching model.