The term “cycloidal CT” refers to a family of efficient sampling strategies that can be applied to x-ray micro-computed tomography (CT) systems which operate with an intensity-modulated beam. Such a beam can be employed to provide access to a phase contrast channel and high spatial resolutions (a few um). Phase contrast can offer better image contrast of samples which have traditionally been “invisible” to x-rays due to their weak attenuation, and high resolutions help view crucial details in samples.

Cycloidal sampling strategies provide images more quickly than the gold standard in the field (“dithering”). I conceived and compared four practical implementation strategies for cycloidal CT, three of which are “flyscans” (the sample moves continuously). Flyscans acquire images of similar resolution to dithering with no overheads, reducing acquisition time to exposure time. I also developed a “knife-edge” position tracking method which tracks subpixel motions of the sample stage. This information can be used to facilitate, automate, and improve the reconstruction of cycloidal data. I analysed the effects of different levels of dose on the signal-to-noise ratio (SNR) of an image acquired with cycloidal CT. The results show that cycloidal images yield the same SNR as dithered images with less dose, although a more extensive study is required. Finally, I explored the potential of using cycloidal CT for intraoperative specimen imaging and tissue engineering. My results are encouraging for tissue engineering; for intraoperative imaging, the cycloidal images did not show comparable resolution to the dithered images, although that is possibly linked to issues with the dataset.

Overall, my work has provided a benchmark for the implementation and application of cycloidal CT for the first time. Besides a summary of my research, this thesis is meant to be a comprehensive guide for facilitating uptake of cycloidal CT within the scientific community and beyond.