A low-cost dual energy CT system with sparse data

Abstract Objectives The purpose of this study was to assess the feasibility of dual-energy CT-based material decomposition using dual-X-ray spectra information to determine local concentrations of holmium microspheres in phantoms and in an animal model. Materials and methods A spectral calibration phantom with a solution containing 10 mg/mL holmium and various tube settings was scanned using a third-generation dual-energy CT scanner to depict an energy-dependent and material-dependent enhancement vectors. A serial dilution of holmium (microspheres) was quantified by spectral material decomposition and compared with known holmium concentrations. Subsequently, the feasibility of the spectral material decomposition was demonstrated in situ in three euthanized rabbits with injected (radioactive) holmium microspheres. Results The measured CT values of the holmium solutions scale linearly to all measured concentrations and tube settings (R2 = 1.00). Material decomposition based on CT acquisitions using the tube voltage combinations of 80/150 Sn kV or 100/150 Sn kV allow the most accurate quantifications for concentrations down to 0.125 mg/mL holmium. Conclusion Dual-energy CT facilitates image-based material decomposition to detect and quantify holmium microspheres in phantoms and rabbits. Key Points • Quantification of holmium concentrations based on dual-energy CT is obtained with good accuracy. • The optimal tube-voltage pairs for quantifying holmium were 80/150 Sn kV and 100/150 Sn kV using a third-generation dual-source CT system. • Quantification of accumulated holmium facilitates the assessment of local dosimetry for radiation therapies.

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Rationale and design of a prospective study on the first integrated PET/dual-energy CT system for staging and image-based radiation therapy planning of lung cancer

European Radiology Experimental ◽

10.1186/s41747-018-0047-4 ◽

2018 ◽

Vol 2 (1) ◽

Cited By ~ 2

Author(s):

Carlo N. De Cecco ◽

Philip Burchett ◽

Marly van Assen ◽

James Ravenel ◽

Samuel Lewis Cooper ◽

...

Keyword(s):

Lung Cancer ◽

Radiation Therapy ◽

Prospective Study ◽

Dual Energy ◽

Dual Energy Ct ◽

Therapy Planning ◽

Radiation Therapy Planning ◽

Ct System ◽

A Prospective Study

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Feasibility of improving vascular imaging in the presence of metallic stents using spectral photon counting CT and K-edge imaging

Scientific Reports ◽

10.1038/s41598-019-56427-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Monica Sigovan ◽

Salim Si-Mohamed ◽

Daniel Bar-Ness ◽

Julia Mitchell ◽

Jean-Baptiste Langlois ◽

...

Keyword(s):

Photon Counting ◽

Dual Energy ◽

Apparent Size ◽

Metallic Stents ◽

Dual Energy Ct ◽

Vascular Calcifications ◽

Vascular Lumen ◽

Ct System ◽

Stent Lumen

AbstractCorrect visualization of the vascular lumen is impaired in standard computed tomography (CT) because of blooming artifacts, increase of apparent size, induced by metallic stents and vascular calcifications. Recently, due to the introduction of photon-counting detectors in the X-ray imaging field, a new prototype spectral photon-counting CT (SPCCT) based on a modified clinical CT system has been tested in a feasibility study for improving vascular lumen delineation and visualization of coronary stent architecture. Coronary stents of different metal composition were deployed inside plastic tubes containing hydroxyapatite spheres to simulate vascular calcifications and in the abdominal aorta of one New Zealand White (NZW) rabbit. Imaging was performed with an SPCCT prototype, a dual-energy CT system, and a conventional 64-channel CT system (B64). We found the apparent widths of the stents significantly smaller on SPCCT than on the other two systems in vitro (p < 0.01), thus closer to the true size. Consequently, the intra-stent lumen was significantly larger on SPCCT (p < 0.01). In conclusion, owing to the increased spatial resolution of SPCCT, improved lumen visualization and delineation of stent metallic mesh is possible compared to dual-energy and conventional CT.

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