Development of a cerebral CT perfusion phantom: A structured approach

Introduction: Computed tomography perfusion (CTP) imaging is crucial in diagnosing and managing vascular diseases, e.g, stroke. Differences in scanners and protocols may lead to different results, affecting clinical decision-making. Objective validation and evaluation of CTP imaging are therefore important. Perfusion phantoms are essential test objects to facilitate the validation and evaluation of perfusion imaging. Therefore, this study aimed to develop, validate and evaluate a brain perfusion phantom for the evaluation of cerebral CTP. Methods: A cerebral perfusion phantom was developed to evaluate CTP imaging of the brain using a workflow based on the Design Science Research Methodology. The reliability and repeatability of the phantom's perfusion parameters derived from the time-density curves (TDCs) in CTP were evaluated. Results: A 3D-printed modular perfusion phantom was developed, filled with sodium alginate beads, and connected to a pumping system to mimic microvasculature and flow dynamics. The phantom consisted of three compartments that simulated different states of perfusion. The phantom showed reliable TDCs, with a relative standard deviation of <6.6 % for peak intensity and time-to-peak (TTP) over two sets of five repeated experiments for all compartments, and repeatable TTP and mean transit time values with a repeatability coefficient of <2.3 s compared to the mean. Conclusions: The developed perfusion phantom demonstrated high reliability and could be employed for investigating CTP imaging under various flow speeds. The presented workflow promotes transparency in the development, validation, and application of CTP phantoms, and facilitates cross-study comparisons through structured iterative development and unified evaluation metrics.