Identification of benign and malignant thyroid nodules by in vivo iodine concentration measurement using single-source dual energy CT

Background and Objectives. Thyroid nodules are increasingly being detected during cross-sectional imaging of the neck and chest. The purpose of this study is to investigate the efficacy of dual-energy computed tomography (DECT) using iodine concentration measurement and multiparametric texture analysis of monochromatic images for differentiating between benign and malignant thyroid nodules. Materials and Methods. This retrospective study included 34 consecutive patients who presented with thyroid nodules and underwent noncontrast DECT between 2015 and 2016. Manual segmentation of each thyroid nodule by monochromatic imaging (40, 60, and 80 keV) was performed, and an in-house developed MATLAB-based texture analysis program was used to extract 41 textures. Iodine material decomposition and CT attenuation slopes were also measured. Histopathologic findings of ultrasound-guided biopsies over a follow-up period of at least one year were used as reference standards. Basic descriptive statistics and areas under receiver operating characteristic curves (AUCs) were evaluated. Results. The 34 nodules comprised 14 benign nodules and 20 malignant nodules. Iodine content and Hounsfield unit curve slopes did not differ significantly between benign and malignant thyroid nodules (P=0.480–0.670). However, significant differences in the texture features of monochromatic images were observed between benign and malignant nodules: histogram mean and median, co-occurrence matrix contrast, gray-level gradient matrix (GLGM) skewness, and mean gradients and variance of gradients for GLGM at 80 keV (P=0.014–0.044). The highest AUC was 0.77, for the histogram mean and median of images acquired at 80 keV. Conclusions. Texture features extracted from monochromatic images using DECT, specifically acquired at high keV, may be a promising diagnostic approach for thyroid nodules. A further large study for incidental thyroid nodules using DECT texture analysis is required to validate our results.

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The Possibility for Iodine Concentration Determination in a Phantom with Known Titers of an Iodine-Containing Contrast Agent, by Using Dual-Energy Computed Tomography

Journal of radiology and nuclear medicine ◽

10.20862/0042-4676-2019-100-6-335-338 ◽

2020 ◽

Vol 100 (6) ◽

pp. 335-338

Author(s):

A. S. Chaban ◽

V. E. Sinitsyn

Keyword(s):

Computed Tomography ◽

Contrast Agent ◽

Measurement Errors ◽

Iodine Concentration ◽

Dual Energy ◽

In Vivo Studies ◽

Single Source ◽

Dual Energy Computed Tomography ◽

True Concentration

Objective: to study the capabilities of single-source dual-energy computed tomography (DECT) in quantifying the concentration of iodine in solutions.Material and methods. Single-source DECT was performed using a phantom containing a set of 5 tubes with a different titer of the iodine-containing contrast agent Iopamidol. Further, the obtained images were used to construct iodine maps; and the concentration of iodine was measured within the volume of the titrated contrast agent.Results. Despite a high correlation between the measured iodine concentration in solution with the true concentration (Pearson's correlation coefficient r = 0.98; p < 0.01), there is a measurement error that was 4.8 to 23% at different dilutions.Conclusion. Signal-source rapid voltage switching DECT does not allow precise measurements of the true concentration of iodine in solution. To eliminate measurement errors in further in vivo studies using singlesource DECT, it may be that attention must be paid to the measurement of normalized iodine concentration.

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How accurate and precise are CT based measurements of iodine concentration? A comparison of the minimum detectable concentration difference among single source and dual source dual energy CT in a phantom study

European Radiology ◽

10.1007/s00330-018-5736-0 ◽

2018 ◽

Vol 29 (4) ◽

pp. 2069-2078 ◽

Cited By ~ 11

Author(s):

André Euler ◽

Justin Solomon ◽

Maciej A. Mazurowski ◽

Ehsan Samei ◽

Rendon C. Nelson

Keyword(s):

Iodine Concentration ◽

Dual Energy ◽

Phantom Study ◽

Dual Energy Ct ◽

Minimum Detectable Concentration ◽

Single Source ◽

Concentration Difference ◽

Detectable Concentration ◽

Dual Source

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Correlation between CT attenuation value and iodine concentration in vitro: Discrepancy between gemstone spectral imaging on single-source dual-energy CT and traditional polychromatic X-ray imaging

Journal of Medical Imaging and Radiation Oncology ◽

10.1111/j.1754-9485.2012.02379.x ◽

2012 ◽

Vol 56 (4) ◽

pp. 379-383 ◽

Cited By ~ 25

Author(s):

Le Wang ◽

Bin Liu ◽

Xing-wang Wu ◽

Jie Wang ◽

Yong Zhou ◽

...

Keyword(s):

Iodine Concentration ◽

Dual Energy ◽

Dual Energy Ct ◽

Single Source ◽

X Ray ◽

Gemstone Spectral Imaging ◽

X Ray Imaging ◽

Ct Attenuation ◽

Ct Attenuation Value

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DUAL ENERGY CT CALIBRATION FOR IN VIVO DETERMINATION OF THYROID IODINE CONCENTRATION

Journal of Computer Assisted Tomography ◽

10.1097/00004728-198505000-00053 ◽

1985 ◽

Vol 9 (3) ◽

pp. 613

Author(s):

F. W. Zonneveld ◽

G. J. Rutherford ◽

P. F. G. M. van Waes

Keyword(s):

Iodine Concentration ◽

Dual Energy ◽

Dual Energy Ct

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Assessing Chemotherapeutic Response in Pancreatic Ductal Adenocarcinoma: Histogram Analysis of Iodine Concentration and CT Number in Single-Source Dual-Energy CT

American Journal of Roentgenology ◽

10.2214/ajr.18.19791 ◽

2018 ◽

Vol 211 (6) ◽

pp. 1221-1226 ◽

Cited By ~ 8

Author(s):

Yoshifumi Noda ◽

Satoshi Goshima ◽

Toshiharu Miyoshi ◽

Hiroshi Kawada ◽

Nobuyuki Kawai ◽

...

Keyword(s):

Pancreatic Ductal Adenocarcinoma ◽

Iodine Concentration ◽

Dual Energy ◽

Histogram Analysis ◽

Ductal Adenocarcinoma ◽

Dual Energy Ct ◽

Single Source ◽

Ct Number ◽

Chemotherapeutic Response

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Iodine quantification and detectability thresholds among major dual-energy CT platforms

British Journal of Radiology ◽

10.1259/bjr.20190530 ◽

2019 ◽

Vol 92 (1104) ◽

pp. 20190530 ◽

Cited By ~ 3

Author(s):

Ross Edward Taylor ◽

Pamela Mager ◽

Nam C. Yu ◽

David P. Katz ◽

Jett R. Brady ◽

...

Keyword(s):

Contrast Material ◽

Iodine Concentration ◽

Dual Energy ◽

Dual Energy Ct ◽

Iodinated Contrast ◽

Detectable Concentration ◽

Sequential Acquisition ◽

Monoenergetic Images

Objectives: To estimate the minimum detectable iodine concentration on multiple dual-energy CT (DECT) platforms. Methods and materials: A phantom containing iodine concentrations ranging from 0 to 10 mg ml−1 was scanned with five dual-energy platforms (two rapid kilo volt switching (r-kVs), one dual source (DS), one sequential acquisition and one split-filter). Serial dilutions of 300 mg ml−1 iodinated contrast material were used to generate concentrations below 2 mg ml−1. Iodine density and virtual monoenergetic images were reviewed by three radiologists to determine the minimum visually detectable iodine concentration. Contrast-to-noise ratios (CNRs) were calculated. Results: 1 mg mL−1 (~0.8 mg mL−1 corrected) was the minimum visually detectable concentration among the platforms and could be seen by all readers on the third-generation r-kVs and DS platforms. Conclusions: At low concentrations, CNR for monoenergetic images was highest on the DS platform and lowest in the sequential acquisition and split-filter platforms. Advances in knowledge: The results of this study corroborate previous in vivo estimates of iodine detection limits at DECT and provide a comparison for the performance of different DECT platforms at low iodine concentrations in vitro.

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Stepwise analysis of potential accuracy-influencing factors of iodine quantification on a fast kVp-switching second-generation dual-energy CT: from 3D-printed phantom to a simple solution in clinical routine use

Acta Radiologica ◽

10.1177/0284185119861312 ◽

2019 ◽

Vol 61 (3) ◽

pp. 424-431 ◽

Cited By ~ 1

Author(s):

Georg Böning ◽

Paul Jahnke ◽

Felix Feldhaus ◽

Uli Fehrenbach ◽

Johannes Kahn ◽

...

Keyword(s):

Influencing Factors ◽

Iodine Concentration ◽

Target Volume ◽

Dual Energy ◽

Concentration Measurement ◽

Dual Energy Ct ◽

Anthropomorphic Phantom ◽

Significant Difference ◽

Applied Dose ◽

3D Printed

Background Measurement of iodine concentration from dual-energy or spectral computed tomography (CT) provides useful diagnostic information especially in patients suffering from malignant tumors of various origins. Purpose The purpose of this study was to systematically investigate the accuracy of the measurement of iodine concentration, focusing on potential influencing factors and assessing its suitability for routine clinical use. Material and Methods First, a 3D-printed cylindrical phantom was used to assess reliability of dual-energy CT-based iodine concentration measurement. Second, a semi-anthropomorphic phantom was used to evaluate the potential impact of positional variation of the target volume as typically seen in clinical scans. Finally, a reference vial was placed on the body surface of 38 patients undergoing abdominal dual-energy CT to analyze correlations between applied doses and patient diameters. Results The position of the target volume within the cylindrical phantom and the applied dose level significantly influenced the magnitude of measured iodine concentrations ( P < 0.001). We also found a significant difference in accuracy depending on target volume position in the semi-anthropomorphic phantom ( P = 0.028). In patient scans, we observed an error of 19.6 ± 5.6% in iodine concentration measurements of a reference and significant, moderate to strong, negative correlations between measured iodine concentration, maximum patient diameter, and applied dose (maximum sagittal diameter: r = −0.455, P = 0.004; maximum coronal diameter: r=−0.517, P = 0.001; CTDIvol: r = −0.385, P = 0.017) Conclusion Dual-energy CT-based iodine concentration measurement should be interpreted with caution. In clinical examinations, placement of a reference vial could be a potential solution to relativize errors.

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