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Original Investigation|Articles in Press

Soft Reconstruction Kernels Improve HCC Imaging on a Photon-Counting Detector CT

  • D. Graafen
    Correspondence
    Address correspondence to: D.G., Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Langenbeckst. 1, 55131 Mainz, Germany.
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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  • L. Müller
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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  • M.C. Halfmann
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)

    German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany (M.C.H., T.E.)
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  • F. Stoehr
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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  • F. Foerster
    Affiliations
    Department of Medicine I, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (F.F.)
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  • C. Düber
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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  • Y. Yang
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
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  • T. Emrich
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)

    German Center for Cardiovascular Research (DZHK), Partner-Site Rhine-Main, Mainz, Germany (M.C.H., T.E.)

    Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (T.E.)
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  • Author Footnotes
    1 Present address: Institute of Interventional Radiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany.
    R. Kloeckner
    Footnotes
    1 Present address: Institute of Interventional Radiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany.
    Affiliations
    Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (D.G., L.M., M.C.H., F.S., C.D., Y.Y., T.E., R.K.)
    Search for articles by this author
  • Author Footnotes
    1 Present address: Institute of Interventional Radiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany.
Published:April 22, 2023DOI:https://doi.org/10.1016/j.acra.2023.03.026

      Rationale and Objectives

      Hepatocellular carcinoma (HCC) is the only tumor entity that allows non-invasive diagnosis based on imaging without further histological proof. Therefore, excellent image quality is of utmost importance for HCC diagnosis. Novel photon-counting detector (PCD) CT improves image quality via noise reduction and higher spatial resolution, inherently providing spectral information. The aim of this study was to investigate these improvements for HCC imaging with triple-phase liver PCD-CT in a phantom and patient population study focusing on identification of the optimal reconstruction kernel.

      Materials and Methods

      Phantom experiments were performed to analyze objective quality characteristics of the regular body and quantitative reconstruction kernels, each with four sharpness levels (36–40–44–48). For 24 patients with viable HCC lesions on PCD-CT, virtual monoenergetic images at 50 keV were reconstructed using these kernels. Quantitative image analysis included contrast-to-noise ratio (CNR) and edge sharpness. Three raters performed qualitative analyses evaluating noise, contrast, lesion conspicuity, and overall image quality.

      Results

      In all contrast phases, the CNR was highest using the kernels with a sharpness level of 36 (all p < 0.05), with no significant influence on lesion sharpness. Softer reconstruction kernels were also rated better regarding noise and image quality (all p < 0.05). No significant differences were found in image contrast and lesion conspicuity. Comparing body and quantitative kernels with equal sharpness levels, there was no difference in image quality criteria, neither regarding in vitro nor in vivo analysis.

      Conclusion

      Soft reconstruction kernels yield the best overall quality for the evaluation of HCC in PCD-CT. As the image quality of quantitative kernels with potential for spectral post-processing is not restricted compared to regular body kernels, they should be preferred.

      Abbreviations:

      PCD (Photon-counting detector), EID (Energy-integrating detector), HCC (Hepatocellular carcinoma), CNR (Contrast-to-noise ratio), DECT (Dual-energy CT), VMI (Virtual monoenergetic image), MTF (Modulation transfer function), CTDI (CT dose index), NPS (Noise power spectrum), ROI (Region of interest), IQR (Interquartile range), DLP (Dose length product)

      Key Words

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      References

        • Fitzmaurice C.
        • Akinyemiju T.
        • Abera S.
        • et al.
        The burden of primary liver cancer and underlying etiologies from 1990 to 2015 at the global, regional, and national level: results from the Global Burden of Disease Study 2015.
        JAMA Oncol. 2017; 3: 1683-1691https://doi.org/10.1001/JAMAONCOL.2017.3055
        • Llovet J.M.
        • Zucman-Rossi J.
        • Pikarsky E.
        • et al.
        Hepatocellular carcinoma.
        Nat Rev Dis Primers. 2016; 2: 1-23https://doi.org/10.1038/nrdp.2016.18
        • Müller L.
        • Hahn F.
        • Jungmann F.
        • et al.
        Quantitative washout in patients with hepatocellular carcinoma undergoing TACE: an imaging biomarker for predicting prognosis.
        Cancer Imaging. 2022; 22: 1-11https://doi.org/10.1186/s40644-022-00446-6
        • Willemink M.J.
        • Persson M.
        • Pourmorteza A.
        • et al.
        Photon-counting CT: technical principles and clinical prospects.
        Radiology. 2018; 289: 293-312https://doi.org/10.1148/radiol.2018172656
        • Flohr T.
        • Petersilka M.
        • Henning A.
        • et al.
        Photon-counting CT review.
        Phys Med. 2020; 79: 126-136https://doi.org/10.1016/j.ejmp.2020.10.030
        • Leng S.
        • Bruesewitz M.
        • Tao S.
        • et al.
        Photon-counting detector CT: system design and clinical applications of an emerging technology.
        Radiographics. 2019; 39: 729-743https://doi.org/10.1148/rg.2019180115
        • Symons R.
        • Reich D.S.
        • Bagheri M.
        • et al.
        Photon-counting CT for vascular imaging of the head and neck: first in vivo human results.
        Invest Radiol. 2018; 53: 135-142https://doi.org/10.1097/RLI.0000000000000418
        • Yu Z.
        • Leng S.
        • Kappler S.
        • et al.
        Noise performance of low-dose CT: comparison between an energy integrating detector and a photon counting detector using a whole-body research photon counting CT scanner.
        J Med Imaging. 2016; 3043503https://doi.org/10.1117/1.JMI.3.4.043503
        • Gutjahr R.
        • Halaweish A.F.
        • Yu Z.
        • et al.
        Human imaging with photon counting-based computed tomography at clinical dose levels: contrast-to-noise ratio and cadaver studies.
        Invest Radiol. 2016; 51: 421-429https://doi.org/10.1097/RLI.0000000000000251
        • Rajagopal J.R.
        • Farhadi F.
        • Solomon J.
        • et al.
        Comparison of low dose performance of photon-counting and energy integrating CT.
        Acad Radiol. 2021; 28: 1754-1760https://doi.org/10.1016/J.ACRA.2020.07.033
        • Symons R.
        • Pourmorteza A.
        • Sandfort V.
        • et al.
        Feasibility of dose-reduced chest CT with photon-counting detectors: initial results in humans.
        Radiology. 2017; 285: 980-989https://doi.org/10.1148/RADIOL.2017162587
        • Zhou W.
        • Michalak G.J.
        • Weaver J.M.
        • et al.
        A universal protocol for abdominal CT examinations performed on a photon-counting detector CT system: a feasibility study.
        Invest Radiol. 2020; 55: 226https://doi.org/10.1097/RLI.0000000000000634
        • Pourmorteza A.
        • Symons R.
        • Sandfort V.
        • et al.
        Abdominal imaging with contrast-enhanced photon-counting CT: first human experience.
        Radiology. 2016; 279: 239-245https://doi.org/10.1148/RADIOL.2016152601
        • Graafen D.
        • Emrich T.
        • Halfmann M.C.
        • et al.
        Dose reduction and image quality in photon-counting detector high-resolution computed tomography of the chest: routine clinical data.
        J Thorac Imaging. 2022; 37: 315-322https://doi.org/10.1097/RTI.0000000000000661
        • Emrich T.
        • O’Doherty J.
        • Schoepf U.J.
        • et al.
        Reduced iodinated contrast media administration in coronary CT angiography on a clinical photon-counting detector CT system.
        Invest Radiol. 2022; 58: 148-155https://doi.org/10.1097/RLI.0000000000000911
        • Graafen D.
        • Müller L.
        • Halfmann M.
        • et al.
        Photon-counting detector CT improves quality of arterial phase abdominal scans: a head-to-head comparison with energy-integrating CT.
        Eur J Radiol. 2022; 156 ([Online ahead of print])https://doi.org/10.1016/J.EJRAD.2022.110514
        • Eldevik K.
        • Nordhøy W.
        • Skretting A.
        Relationship between sharpness and noise in CT images reconstructed with different kernels.
        Radiat Prot Dosimetry. 2010; 139: 430-433https://doi.org/10.1093/RPD/NCQ063
        • Wang Y.
        • de Bock G.H.
        • van Klaveren R.J.
        • et al.
        Volumetric measurement of pulmonary nodules at low-dose chest CT: Effect of reconstruction setting on measurement variability.
        Eur Radiol. 2010; 20: 1180-1187https://doi.org/10.1007/S00330-009-1634-9/
        • Achenbach S.
        • Boehmer K.
        • Pflederer T.
        • et al.
        Influence of slice thickness and reconstruction kernel on the computed tomographic attenuation of coronary atherosclerotic plaque.
        J Cardiovasc Comput Tomogr. 2010; 4: 110-115https://doi.org/10.1016/j.jcct.2010.01.013
        • Funama Y.
        • Oda S.
        • Utsunomiya D.
        • et al.
        Coronary artery stent evaluation by combining iterative reconstruction and high-resolution kernel at coronary CT angiography.
        Acad Radiol. 2012; 19: 1324-1331https://doi.org/10.1016/j.acra.2012.06.013
        • Paul J.
        • Krauss B.
        • Banckwitz R.
        • et al.
        Relationships of clinical protocols and reconstruction kernels with image quality and radiation dose in a 128-slice CT scanner: study with an anthropomorphic and water phantom.
        Eur J Radiol. 2012; 81: 699-713https://doi.org/10.1016/j.ejrad.2011.01.078
        • Smith T.B.
        • Zhang S.
        • Erkanli A.
        • et al.
        Variability in image quality and radiation dose within and across 97 medical facilities.
        J Med Imaging (Bellingham). 2021; 8: 052105https://doi.org/10.1117/1.JMI.8.5.052105
        • Juntunen M.A.K.
        • Rautiainen J.
        • Hänninen N.E.
        • et al.
        Harmonization of technical image quality in computed tomography: comparison between different reconstruction algorithms and kernels from six scanners.
        Biomed Phys Eng Express. 2022; 8https://doi.org/10.1088/2057-1976/AC605B
        • Higashigaito K.
        • Euler A.
        • Eberhard M.
        • et al.
        Contrast-enhanced abdominal CT with clinical photon-counting detector CT: assessment of image quality and comparison with energy-integrating detector CT.
        Acad Radiol. 2022; 29: 689-697https://doi.org/10.1016/j.acra.2021.06.018
        • Bette S.
        • Decker J.A.
        • Braun F.M.
        • et al.
        Optimal conspicuity of liver metastases in virtual monochromatic imaging reconstructions on a novel photon-counting detector CT-effect of keV settings and BMI.
        Diagnostics (Basel). 2022; 12: 1231https://doi.org/10.3390/DIAGNOSTICS12051231
        • Sartoretti T.
        • Landsmann A.
        • Nakhostin D.
        • et al.
        Quantum iterative reconstruction for abdominal photon-counting detector CT improves image quality.
        Radiology. 2022; 303: 339-348https://doi.org/10.1148/radiol.211931
        • Anam C.
        • Fujibuchi T.
        • Haryanto F.
        • et al.
        Automated MTF measurement in CT images with a simple wire phantom.
        Pol J Med Phys Eng. 2019; 25: 179-187https://doi.org/10.2478/pjmpe-2019-0024
        • Friedman S.N.
        • Fung G.S.K.
        • Siewerdsen J.H.
        • et al.
        A simple approach to measure computed tomography (CT) modulation transfer function (MTF) and noise-power spectrum (NPS) using the American College of Radiology (ACR) accreditation phantom.
        Med Phys. 2013; 40: 051907https://doi.org/10.1118/1.4800795
        • Schneider C.A.
        • Rasband W.S.
        • Eliceiri K.W.
        NIH Image to ImageJ: 25 years of image analysis.
        Nat Methods. 2012; 9: 671-675https://doi.org/10.1038/nmeth.2089
        • Pan T.
        • Hasegawa A.
        • Luo D.
        • et al.
        Technical note: impact on central frequency and noise magnitude ratios by advanced CT image reconstruction techniques.
        Med Phys. 2020; 47: 480-487https://doi.org/10.1002/MP.13937
        • Ohkubo M.
        • Wada S.
        • Ida S.
        • et al.
        Determination of point spread function in computed tomography accompanied with verification.
        Med Phys. 2009; 36: 2089-2097https://doi.org/10.1118/1.3123762
        • Pregler B.
        • Beyer L.P.
        • Teufel A.
        • et al.
        Low tube voltage liver MDCT with sinogram-affirmed iterative reconstructions for the detection of hepatocellular carcinoma.
        Sci Rep. 2017; 7: 9460https://doi.org/10.1038/S41598-017-10095-6
        • Ichikawa S.
        • Motosugi U.
        • Shimizu T.
        • et al.
        Diagnostic performance and image quality of low-tube voltage and low-contrast medium dose protocol with hybrid iterative reconstruction for hepatic dynamic CT.
        Br J Radiol. 2021; 94: 20210601https://doi.org/10.1259/BJR.20210601
        • Yu M.H.
        • Lee J.M.
        • Yoon J.H.
        • et al.
        Low tube voltage intermediate tube current liver MDCT: sinogram-affirmed iterative reconstruction algorithm for detection of hypervascular hepatocellular carcinoma.
        Am J Roentgenol. 2013; 201: 23-32https://doi.org/10.2214/AJR.12.10000
        • Hur S.
        • Lee J.M.
        • Kim S.J.
        • et al.
        80-kVp CT using iterative reconstruction in image space algorithm for the detection of hypervascular hepatocellular carcinoma: phantom and initial clinical experience.
        Korean J Radiol. 2012; 13: 152-164https://doi.org/10.3348/kjr.2012.13.2.152
        • Mergen V.
        • Eberhard M.
        • Manka R.
        • et al.
        First in-human quantitative plaque characterization with ultra-high resolution coronary photon-counting CT angiography.
        Front Cardiovasc Med. 2022; 9: 981012https://doi.org/10.3389/FCVM.2022.981012
        • Mergen V.
        • Sartoretti T.
        • Baer-Beck M.
        • et al.
        Ultra-high-resolution coronary CT angiography with photon-counting detector CT: feasibility and image characterization.
        Invest Radiol. 2022; 57: 780-788https://doi.org/10.1097/RLI.0000000000000897
        • Sartoretti T.
        • Mergen V.
        • Jungblut L.
        • et al.
        Liver iodine quantification with photon-counting detector CT: accuracy in an abdominal phantom and feasibility in patients.
        Acad Radiol. 2022; 30: 461-469https://doi.org/10.1016/J.ACRA.2022.04.021
        • Hertel A.
        • Tharmaseelan H.
        • Rotkopf L.T.
        • et al.
        Phantom-based radiomics feature test-retest stability analysis on photon-counting detector CT.
        Eur Radiol. 2023; ([Online ahead of print])https://doi.org/10.1007/S00330-023-09460-Z
        • Tharmaseelan H.
        • Rotkopf L.T.
        • Ayx I.
        • et al.
        Evaluation of radiomics feature stability in abdominal monoenergetic photon counting CT reconstructions.
        Sci Rep. 2022; 12: 19594https://doi.org/10.1038/S41598-022-22877-8
        • Sharma S.
        • Pal D.
        • Abadi E.
        • et al.
        Can photon-counting CT improve estimation accuracy of morphological radiomics features? A simulation study for assessing the quantitative benefits from improved spatial resolution in deep silicon-based photon-counting CT.
        Acad Radiol. 2022; ([Online ahead of print])https://doi.org/10.1016/J.ACRA.2022.06.018
        • Fronda M.
        • Doriguzzi Breatta A.
        • Gatti M.
        • et al.
        Quantitative assessment of HCC wash-out on CT is a predictor of early complete response to TACE.
        Eur Radiol. 2021; 31: 6578-6588https://doi.org/10.1007/S00330-021-07792-2
        • Mallinson P.I.
        • Coupal T.
        • Reisinger C.
        • et al.
        Artifacts in dual-energy CT gout protocol: a review of 50 suspected cases with an artifact identification guide.
        AJR. 2014; 203: 103-109https://doi.org/10.2214/AJR.13.11396
        • Parakh A.
        • An C.
        • Lennartz S.
        • et al.
        Recognizing and minimizing artifacts at dual-energy CT.
        Radiographics. 2021; 41: 509-523https://doi.org/10.1148/rg.2021200049
        • Racine D.
        • Mergen V.
        • Viry A.
        • et al.
        Photon-counting detector CT with quantum iterative reconstruction.
        Invest Radiol. 2022; 58 (Publ. Ahead of Print): 245-252https://doi.org/10.1097/RLI.0000000000000925