Refinement of clinical X-ray computed tomography (CT) scans containing metal implants
X-ray Computed Tomography (CT) data contains artefacts from many sources and these are sufficiently prominent to affect diagnostic utility when metal is present in the scans. Several techniques have been proposed to reduce these artefacts, the most successful involving the removal and filling in of any sinogram data which has been affected by metal. Most such techniques are prone to introducing new artefacts into the CT data or may take a long time to correct the data. In this paper, a new technique is proposed which is fast, yet can effectively remove most artefacts without introducing significant new ones. This is thoroughly tested against both published and commercial alternatives, quantitatively on phantom data, and qualitatively on a selection of clinical scans, mostly of the hip. The phantom data is from two recently published studies, enabling direct comparison with the technique presented here. The results show an improvement in reducing artefacts on phantom data, in most cases significant at p < 0:001, with similar qualitative improvements on clinical data, particularly for bony features close to metal implants.