Comparison study of image quality and effective dose in dual energy chest digital tomosynthesis

Background Dual-energy computed tomography (DECT) has conceptually been known since the late 1970s and commercially available as dual-source CT (DSCT) systems since 2006; however, the technique has not yet seen widespread implementation in routine protocols. Part of the cause for this is likely due to misconceptions about radiation dose and/or image quality when using DECT. Purpose To compare image quality and radiation dose of single-energy CT (SECT) and DECT abdominal examinations obtained in clinical practice on a second generation DSCT. Material and Methods A total of 495 included patients (mean age = 70.9 years) were retrospectively analyzed after undergoing either SECT (120 kVp and age-based mAs) or DECT examinations (80/Sn140 kVp and age-based mAs). The patients were divided into two groups based on examination type (247 SECT, 248 DECT), which were then subdivided into two groups, each based on age. Image noise was measured in the liver and image quality was subjectively assessed in 100 randomly selected patients. Results Noise levels were significantly lower in DECT (13.9 HU) compared with SECT (14.7 HU) ( P < 0.05). No significant differences in subjective image quality were found between DECT and SECT, except for one criterion in the 50–74-year age group. The mean dose-length product (DLP) (376 mGy-cm) and effective dose (6.1 mSv) of DECT were significantly lower than the DLP (513 mGy-cm) and effective dose (8.4 mSv) of SECT ( P < 0.05). Conclusion DECT can be implemented in routine clinical use without negatively impacting image quality while lowering radiation dose to the patient.

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Comparison study of noise reduction algorithms in dual energy chest digital tomosynthesis

Journal of Instrumentation ◽

10.1088/1748-0221/13/04/t04001 ◽

2018 ◽

Vol 13 (04) ◽

pp. T04001-T04001 ◽

Cited By ~ 1

Author(s):

D. Lee ◽

Y.-S. Kim ◽

S. Choi ◽

H. Lee ◽

S. Choi ◽

...

Keyword(s):

Noise Reduction ◽

Dual Energy ◽

Digital Tomosynthesis ◽

Comparison Study

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Comparison of dose and image quality of dual-energy CT pulmonary angiografy on 2nd and 3 rd generation dual-source scanners

RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren ◽

10.1055/s-0035-1550807 ◽

2015 ◽

Vol 187 (S 01) ◽

Author(s):

S Fischer ◽

N Schultheis ◽

P Dewes ◽

J Scholtz ◽

M Kerl ◽

...

Keyword(s):

Image Quality ◽

Dual Energy ◽

Dual Energy Ct ◽

Dual Source

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Faculty Opinions recommendation of Magnetic resonance imaging of the prostate at 1.5 versus 3.0T: A prospective comparison study of image quality.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727719412.793549259 ◽

2018 ◽

Author(s):

Ardeshir Rastinehad

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Image Quality ◽

Comparison Study ◽

Resonance Imaging ◽

Prospective Comparison

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Threshold-dependent iodine imaging and spectral separation in a whole-body photon-counting CT system

European Radiology ◽

10.1007/s00330-021-07786-0 ◽

2021 ◽

Author(s):

S. Sawall ◽

L. Klein ◽

E. Wehrse ◽

L. T. Rotkopf ◽

C. Amato ◽

...

Keyword(s):

Image Quality ◽

Photon Counting ◽

Dual Energy ◽

Whole Body ◽

Dual Energy Ct ◽

Post Mortem ◽

Tube Voltage ◽

Spectral Separation ◽

Dual Source ◽

Noise Ratio

Abstract Objective To evaluate the dual-energy (DE) performance and spectral separation with respect to iodine imaging in a photon-counting CT (PCCT) and compare it to dual-source CT (DSCT) DE imaging. Methods A semi-anthropomorphic phantom extendable with fat rings equipped with iodine vials is measured in an experimental PCCT. The system comprises a PC detector with two energy bins (20 keV, T) and (T, eU) with threshold T and tube voltage U. Measurements using the PCCT are performed at all available tube voltages (80 to 140 kV) and threshold settings (50–90 keV). Further measurements are performed using a conventional energy-integrating DSCT. Spectral separation is quantified as the relative contrast media ratio R between the energy bins and low/high images. Image noise and dose-normalized contrast-to-noise ratio (CNRD) are evaluated in resulting iodine images. All results are validated in a post-mortem angiography study. Results R of the PC detector varies between 1.2 and 2.6 and increases with higher thresholds and higher tube voltage. Reference R of the EI DSCT is found as 2.20 on average overall phantoms. Maximum CNRD in iodine images is found for T = 60/65/70/70 keV for 80/100/120/140 kV. The highest CNRD of the PCCT is obtained using 140 kV and is decreasing with decreasing tube voltage. All results could be confirmed in the post-mortem angiography study. Conclusion Intrinsically acquired DE data are able to provide iodine images similar to conventional DSCT. However, PCCT thresholds should be chosen with respect to tube voltage to maximize image quality in retrospectively derived image sets. Key Points • Photon-counting CT allows for the computation of iodine images with similar quality compared to conventional dual-source dual-energy CT. • Thresholds should be chosen as a function of the tube voltage to maximize iodine contrast-to-noise ratio in derived image sets. • Image quality of retrospectively computed image sets can be maximized using optimized threshold settings.

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Deep learning image reconstruction algorithm for pancreatic protocol dual-energy computed tomography: image quality and quantification of iodine concentration

European Radiology ◽

10.1007/s00330-021-08121-3 ◽

2021 ◽

Author(s):

Yoshifumi Noda ◽

Nobuyuki Kawai ◽

Shoma Nagata ◽

Fumihiko Nakamura ◽

Takayuki Mori ◽

...

Keyword(s):

Computed Tomography ◽

Deep Learning ◽

Image Reconstruction ◽

Image Quality ◽

Reconstruction Algorithm ◽

Iodine Concentration ◽

Dual Energy ◽

Image Reconstruction Algorithm ◽

Tomography Image ◽

Computed Tomography Image

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Metal artefact reduction of different alloys with dual energy computed tomography (DECT)

Scientific Reports ◽

10.1038/s41598-021-81600-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Anand John Vellarackal ◽

Achim Hermann Kaim

Keyword(s):

Stainless Steel ◽

Image Quality ◽

Femoral Stem ◽

Dual Energy ◽

Dual Energy Ct ◽

Bony Tissue ◽

Stem Image ◽

Metal Artefact ◽

Artefact Reduction

AbstractTo evaluate the influence of dual-energy CT (DECT) and Virtual monochromatic spectral (VMS) imaging on: (1) the artefact size of geometrically identical orthopaedic implants consisting of three different compositions and (2) the image quality of the surrounding bone, three similar phantoms—each featuring one femoral stem composed of either titanium, chrome-cobalt or stainless steel surrounded by five calcium pellets (200 mg hydroxyapatite/calcium carbonate) to simulate bony tissue and one reference pellet located away from the femoral stem—were built. DECT with two sequential scans (80 kVp and 140 kVp; scan-to-scan technique) was performed, and VMS images were calculated between 40 and 190 keV. The artefact sizes were measured volumetrically by semiautomatic selection of regions of interest (ROIs), considering the VMS energies and the polychromatic spectres. Moreover, density and image noise within the pellets were measured. All three phantoms exhibit artefact size reduction as energy increases from 40 to 190 keV. Titanium exhibited a stronger reduction than chrome-cobalt and stainless steel. The artefacts were dependent on the diameter of the stem. Image quality increases with higher energies on VMS with a better depiction of surrounding structures. Monoenergetic energies 70 keV and 140 keV demonstrate superior image quality to those produced by spectral energies 80 kVp and 140 kVp.

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