Development of an anatomically realistic renal flow phantom

Objectives: Ultrasound flow phantoms are used to test both the accuracy of the ultrasound scanners (maximum velocity estimation) and the physical assumptions (mean tissue speed of sound, flow profile of blood). They contain vessel, tissue and blood mimicking structures and a computer controlled pump system. Despite the availability of a variety of flow phantoms none currently exists which mimics the renal vasculature. The novel aspect of this study is the development of an anatomically realistic renal flow phantom with the ability to mimic the geometry of a stenosis in the renal artery.

Methods: Computer-aided modelling techniques were used to generate anatomical phantoms of the renal artery from medical images of a 64-slice CT scan of the abdominal region acquired from a healthy volunteer with normal renal vasculature. From this data a computer model of the renal artery (diameter 6.8mm) was generated. Using a 3D printer a physical model of the renal artery was produced. An investment casting technique was used to fabricate the flow phantoms.

Results: A number of realistic flow phantoms with the ability to mimic the geometry of the renal artery with different grades of stenosis were developed.

Conclusions: These novel renal phantoms will provide a means of evaluating current and emerging ultrasound technologies as well as being able to image and understand the hemodynamic features within the renal artery in health and disease.