Dataset Information

First-generation clinical dual-source photon-counting CT: ultra-low-dose quantitative spectral imaging.

ABSTRACT:

Objective

Evaluation of image characteristics at ultra-low radiation dose levels of a first-generation dual-source photon-counting computed tomography (PCCT) compared to a dual-source dual-energy CT (DECT) scanner.

Methods

A multi-energy CT phantom was imaged with and without an extension ring on both scanners over a range of radiation dose levels (CTDI_vol 0.4-15.0 mGy). Scans were performed in different modes of acquisition for PCCT with 120 kVp and DECT with 70/Sn150 kVp and 100/Sn150 kVp. Various tissue inserts were used to characterize the precision and repeatability of Hounsfield units (HUs) on virtual mono-energetic images between 40 and 190 keV. Image noise was additionally investigated at an ultra-low radiation dose to illustrate PCCT's ability to remove electronic background noise.

Results

Our results demonstrate the high precision of HU measurements for a wide range of inserts and radiation exposure levels with PCCT. We report high performance for both scanners across a wide range of radiation exposure levels, with PCCT outperforming at low exposures compared to DECT. PCCT scans at the lowest radiation exposures illustrate significant reduction in electronic background noise, with a mean percent reduction of 74% (p value ~ 10^-8) compared to DECT 70/Sn150 kVp and 60% (p value ~ 10^-6) compared to DECT 100/Sn150 kVp.

Conclusions

This paper reports the first experiences with a clinical dual-source PCCT. PCCT provides reliable HUs without disruption from electronic background noise for a wide range of dose values. Diagnostic benefits are not only for quantification at an ultra-low dose but also for imaging of obese patients.

Key points

PCCT scanners provide precise and reliable Hounsfield units at ultra-low dose levels. The influence of electronic background noise can be removed at ultra-low-dose acquisitions with PCCT. Both spectral platforms have high performance along a wide range of radiation exposure levels, with PCCT outperforming at low radiation exposures.

SUBMITTER: Liu LP

PROVIDER: S-EPMC10071880 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Publications

First-generation clinical dual-source photon-counting CT: ultra-low-dose quantitative spectral imaging.

Liu Leening P LP Shapira Nadav N Chen Andrew A AA Shinohara Russell T RT Sahbaee Pooyan P Schnall Mitchell M Litt Harold I HI Noël Peter B PB

European radiology 20220616 12

<h4>Objective</h4>Evaluation of image characteristics at ultra-low radiation dose levels of a first-generation dual-source photon-counting computed tomography (PCCT) compared to a dual-source dual-energy CT (DECT) scanner.<h4>Methods</h4>A multi-energy CT phantom was imaged with and without an extension ring on both scanners over a range of radiation dose levels (CTDI<sub>vol</sub> 0.4-15.0 mGy). Scans were performed in different modes of acquisition for PCCT with 120 kVp and DECT with 70/Sn150 ...[more]

PMID: 35708838

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Dataset Information

First-generation clinical dual-source photon-counting CT: ultra-low-dose quantitative spectral imaging.

Objective

Methods

Results

Conclusions

Key points

Publications

First-generation clinical dual-source photon-counting CT: ultra-low-dose quantitative spectral imaging.

Similar Datasets

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