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with a stand, and personnel hold the rope from an adjacent lead shielded cabin. This set-up has been used and recommended in standing CT of the equine head (Dakin et al. 2014). It has been reported that the estimated dose for the personnel under these circumstances ranged between 0 and 5 µSv per scan (Dakin et al. 2014). More recently, cone beam CT units have been
introduced to the equine market for performing the CT in standing patients. Despite improved spatial resolution and isotropic voxel dimensions, cone beam CTs possess disadvantages compared with multi-slice systems, including increased motion susceptibility (long acquisition time), decreased contrast resolution and Hounsfield unit variability (Nelson et al. 2017). Regarding the image quality, multi-slice CT shows a greater ability to produce clear and anatomically correct images, and with better soft tissue differentiation compared with the cone beam CT (Nelson et al. 2017). Optimisation and development of this CT unit is still in
progress. Since the motion artefact was the most common reason for poor image quality and scans repeating, we hope for motion correction software to be adapted in the future. In human medicine, a rigid motion correction method has been used to eliminate or reduce the motion artefact by 90% in the multi-slice helical system (Kim et al. 2015). The current report showed that a multi-slice helical CT
scanner built over a platform facilitates scanning the distal limb of standing horses with a good diagnostic image quality. Imaging of the feet and metacarpo(tarso)phalangeal region of both front and hindlimbs can be performed easily. Although more prone to movement artefact, image acquisition with diagnostic quality of the proximal limb is also achievable in some cases. We believe this technique could improve the assessment of distal limb pathology.
Author’s declaration of interests No conflicts of interest have been declared.
Ethical animal research
This is a retrospective designed study. No names or patient- owner data have been used.
Acknowledgement The author would like to thank Dr Copper Williams for revising the article.
Manufacturers’ addresses
1Toshiba, Berlin, Germany 2Orion Pharma, Hamburg, Germany 3Zoetis GmbH, Berlin, Germany
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