Optimising Propagation-Based Phase Contrast X-Ray Imaging for Enhanced Resolution and Reduced Radiation Dose

X-ray Computed Tomography, commonly known as CT, is an essential tool in clinical diagnostics, but can only be used sparingly due to safety limits based on its use of ionising radiation. This challenge has inspired the development of so-called phase contrast techniques, which additionally harness the phase information encoded in X-ray waves. This thesis explores the application of propagation-based phase-contrast X-ray imaging to enable much higher-resolutions than currently achieved in clinical CT, while maintaining very low radiation dose. Modifications to existing algorithms are explored before presenting a synchrotron-based, pre-clinical demonstration for paediatric lung imaging and initial steps towards clinical compatibility.