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Flat panel cone-beam computed tomography (CBCT) is developing to the state-of-the-art technique in several
medical disciplines such as dental and otorhinolaryngological imaging. Dental and otorhinolaryngological CBCT
systems offer a variety of different field-of-view sizes from 6.0 to 17.0 cm. Standard phantoms are only designed for the
use in multi-slices CT (MSCT) and there is no phantom which provides detail structures for all common characteristic
values and Hounsfield calibration. In this study we present a new phantom specially designed for use with MSCT and
CBCT systems providing detail structures for MTF, 3D MTF, NPS, SNR, geometric distortion and HU calibration. With
this phantom you'll only need one acquisition for image quality investigation and assurance. Materials and methods:
The phantom design is shown in figure 1. To investigate the practicability, the phantom was scanned using dedicated
MSCT-scanners, 3D C-arms und digital volume tomographs. The acquired axial image stacks were analyzed using a
dedicated computer program, which is provided as an ImageJ plugin. The MTF was compared to other methodologies
such as a thin wire, a sphere or noise response [10, 13, 14]. The HU values were also computed using other common
methods. Results: These results are similar to the results of others studies [10, 13, 14]. The method has proven to be
stable and delivers comparable results to other methodologies such as using a thin wire. The NPS was calculated for all
materials. Furthermore, CT numbers for all materials were computed and compared to the desired values. The
measurement of geometric deformation has proven to be accurate. Conclusion: A unique feature of this phantom is to
compute the geometric deformation of the 3D-volume image. This offers the chance to improve accuracy, e.g. in dental
implant planning. Another convenient feature is that the phantom needs to be scanned only once with
otorhinolaryngological volume tomographs to be fully displayed. It is shown, that this new phantom provides amazing
potential for image quality assurance in MSCT as well as in CBCT. It contains detail structures for all characteristic
image quality values. In combination with a software tool it is the silver bullet for image quality assurance.
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