Bi-HPDO3A as a novel contrast agent for X-ray computed tomography.
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ABSTRACT:
SUBMITTER: Rizzo R
PROVIDER: S-EPMC10556142 | biostudies-literature | 2023 Oct
REPOSITORIES: biostudies-literature
Publications
Bi-HPDO3A as a novel contrast agent for X-ray computed tomography.
Rizzo Rebecca R Capozza Martina M Carrera Carla C Terreno Enzo E
Scientific reports 20231005 1
A new bismuth-based CT agent was synthesized through a facile synthesis strategy. The in vitro stability, toxicity and CT performance were evaluated. The in vivo imaging performance was investigated using three different doses (0.5, 1.2 and 5 mmol/kg) and the result obtained at 1.2 mmol/kg was compared with the clinically approved CT agent iopamidol at the same dosage. ...[more]
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Project description:X-ray phase-contrast tomography can significantly increase the contrast-resolution of conventional attenuation-contrast imaging, especially for soft-tissue structures that have very similar attenuation. Just as in attenuation-based tomography, phase contrast tomography requires a linear dependence of aggregate beam direction on the incremental direction alteration caused by individual voxels along the path of the X-ray beam. Dense objects such as calcifications in biological specimens violate this condition. There are extensive beam deflection artefacts in the vicinity of such structures because they result in large distortion of wave front due to the large difference of refractive index; for such large changes in beam direction, the transmittance of the silicon analyzer crystal saturates and is no longer linearly dependent on the angle of refraction. This paper describes a method by which these effects can be overcome and excellent soft-tissue contrast of phase tomography can be preserved in the vicinity of such artefact-producing structures.
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