Accuracy of bone mineral density quantification using dual-layer spectral detector CT: a phantom study

Hamersvelt, Robbert W. van; Schilham, Arnold M. R.; Engelke, Klaus; Harder, Annemarie M. den; Keizer, Bart de; Verhaar, Harald J. J.; Leiner, Tim; Jong, Pim A. de; Willemink, Martin J.

doi:10.1007/s00330-017-4801-4

Cited by 67 publications

(44 citation statements)

References 28 publications

(39 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A number of studies have been conducted on the dual‐layer technology, primarily looking at applications of dual‐energy analysis . However, only few studies have yet been published on image quality of conventional images acquired on the IQon .…”

Section: Discussionmentioning

confidence: 99%

“…A number of studies have been conducted on the duallayer technology, primarily looking at applications of dualenergy analysis. 5,[9][10][11][12][13][14][15] However, only few studies have yet been published on image quality of conventional images acquired on the IQon. 16 In general, the conventional images acquired on the IQon are very similar to images acquired on the iCT, as can be seen in Fig.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Image quality of conventional images of dual‐layer SPECTRAL CT: A phantom study

et al. 2018

View full text Add to dashboard Cite

Purpose: Spectral CT using a dual layer detector offers the possibility of retrospectively introducing spectral information to conventional CT images. In theory, the dual-layer technology should not come with a dose or image quality penalty for conventional images. In this study, we evaluate the influence of a dual-layer detector (IQon Spectral CT, Philips Healthcare) on the image quality of conventional CT images, by comparing these images with those of a conventional but otherwise technically comparable single-layer CT scanner (Brilliance iCT, Philips Healthcare), by means of phantom experiments. Methods: For both CT scanners, conventional CT images were acquired using four adult scanning protocols: (a) body helical, (b) body axial, (c) head helical, and (d) head axial. A CATPHAN 600 phantom was scanned to conduct an assessment of image quality metrics at equivalent (CTDI) dose levels. Noise was characterized by means of noise power spectra (NPS) and standard deviation (SD) of a uniform region, and spatial resolution was evaluated with modulation transfer functions (MTF) of a tungsten wire. In addition, contrast-to-noise ratio (CNR), image uniformity, CT number linearity, slice thickness, slice spacing, and spatial linearity were measured and evaluated. Additional measurements of CNR, resolution and noise were performed in two larger phantoms. Results: The resolution levels at 50%, 10%, and 5% MTF of the iCT and IQon showed small, but significant differences up to 0.25 lp/cm for body scans, and up to 0.2 lp/cm for head scans in favor of the IQon. The iCT and IQon showed perfect CT linearity for body scans, but for head scans both scanners showed an underestimation of the CT numbers of materials with a high opacity. Slice thickness was slightly overestimated for both scanners. Slice spacing was comparable and reconstructed correctly. In addition, spatial linearity was excellent for both scanners, with a maximum error of 0.11 mm. CNR was higher on the IQon compared to the iCT for both normal and larger phantoms with differences up to 0.51. Spatial resolution did not change with phantom size, but noise levels increased significantly. For head scans, IQon had a noise level that was significantly lower than the iCT, on the other hand IQon showed noise levels significantly higher than the iCT for body scans. Still, these differences were well within the specified range of performance of iCT scanners. Conclusions: At equivalent dose levels, this study showed similar quality of conventional images acquired on iCT and IQon for medium-sized phantoms and slightly degraded image quality for (very) large phantoms at lower tube voltages on the IQon. Accordingly, it may be concluded that the introduction of a dual-layer detector neither compromises image quality of conventional images nor increases radiation dose for normal-sized patients, and slightly degrades dose efficiency for large patients at 120 kVp and lower tube voltages.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Image quality of conventional images of dual‐layer SPECTRAL CT: A phantom study

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Performing MD in projection space is preferable as the modeling of X-ray attenuation theoretically eliminates beam hardening [15]. MD based on multi-energy data has been successfully used for quantification of iodine [8], [9], gadolinium [9], and lipid [16] content, as well as the amount of Calcium Hydroxyapatite (CaHA) [7], [17], which is required for the assessment of bone mineral density. These studies have shown strong correlations with measured and true concentrations, confirming that spectral CT can be used for quantitative MD and tissue discrimination.…”

Section: Introductionmentioning

confidence: 99%

Framework for Photon Counting Quantitative Material Decomposition

Juntunen¹,

Inkinen²,

Ketola³

et al. 2020

IEEE Trans. Med. Imaging

View full text Add to dashboard Cite

In this paper, the accuracy of material decomposition (MD) using an energy discriminating photon counting detector was studied. An MD framework was established and validated using calcium hydroxyapatite (CaHA) inserts of known densities (50 mg/cm 3 , 100 mg/cm 3 , 250 mg/cm 3 , 400 mg/cm 3), and diameters (1.2, 3.0, and 5.0 mm). These inserts were placed in a cardiac rod phantom that mimics a tissue equivalent heart and measured using an experimental photon counting detector cone beam computed tomography (PCD-CBCT) setup. The quantitative coronary calcium scores (density, mass, and volume) obtained from the MD framework were compared with the nominal values. In addition, three different calibration techniques, signal-to-equivalent thickness calibration (STC), polynomial correction (PC), and projected equivalent thickness calibration (PETC) were compared to investigate the effect of the calibration method on the quantitative values. The obtained MD estimates agreed well with the nominal values for density (mass) with mean absolute percent errors (MAPEs) 8 ± 11% (9 ± 15%) and 4 ± 6% (9 ± 14%) for STC and PETC calibration methods, respectively. PC displayed large MAPEs for density (27 ± 9%), and mass (25 ± 12%). Volume estimation resulted in large deviations between true and measured values with notable MAPEs for STC (40 ± 90%), PC (40 ± 80%), and PETC (40 ± 90%). The framework demonstrated the feasibility of quantitative CaHA mass and density scoring using PCD-CBCT.

show abstract

“…A recent phantom study by von Hamersvelt et al. (8) demonstrated measurement errors < 6% when density measurements were compared to known densities using a DECT scanner. BMD measured by CT has been examined in previous studies (1,2,9–14), but only within-scan reliability was assessed and thus measurement error induced by repeated positioning and re-scanning was not accounted for in those studies.…”

Section: Introductionmentioning

confidence: 99%

Bone density measurements adjacent to acetabular cups in total hip arthroplasty using dual-energy CT: an in vivo reliability and agreement study

Mussmann

Andersen

Torfing

et al. 2018

Acta Radiologica Open

View full text Add to dashboard Cite

BackgroundMeasuring bone mineral density (BMD) around acetabular prosthetic components with computed tomography (CT) is challenged by the complex anatomy and metal artifacts. Three-dimensional (3D) segmentation is required for the analysis, but it is usually not practically applicable on current CT workstationsPurposeTo test the between-scan agreement and reliability of custom segmentation software for BMD measurements adjacent to cemented and uncemented acetabular cups in dual-energy CT (DECT).Material and MethodsTwenty-four male patients with total hip arthroplasty were scanned and rescanned using 130-keV virtual monochromatic DECT images. Hemispherical regions of interest were defined slice-by-slice and BMD was calculated around the acetabular cup using custom segmentation software.ResultsIn the uncemented cup, the mean BMD was 153 mg/cm3 with a between-scan difference of 10 mg/cm3 (P < 0.0001). In the cemented cup, the mean BMD was 186 mg/cm3 with a between-scan difference of 6 mg/cm3 (P = 0.15). In both uncemented and cemented cups the intraclass correlation coefficient between repeated measurements was >0.95 and narrow Bland–Altman Limits of Agreement.ConclusionBMD can be measured with high absolute between-scan agreement and good reliability adjacent to acetabular cemented and uncemented cups using DECT and segmentation software.

show abstract

Accuracy of bone mineral density quantification using dual-layer spectral detector CT: a phantom study

Cited by 67 publications

References 28 publications

Image quality of conventional images of dual‐layer SPECTRAL CT: A phantom study

Image quality of conventional images of dual‐layer SPECTRAL CT: A phantom study

Framework for Photon Counting Quantitative Material Decomposition

Bone density measurements adjacent to acetabular cups in total hip arthroplasty using dual-energy CT: an in vivo reliability and agreement study

Contact Info

Product

Resources

About