Intra-individual Differences in Pericoronary Fat Attenuation Index Measurements Between Photon-counting and Energy-integrating Detector Computed Tomography

Giuseppe Tremamunno; Milan Vecsey-Nagy; Muhammad Taha Hagar; U Joseph Schoepf; Jim O'Doherty; Julian A Luetkens; Daniel Kuetting; Alexander Isaak; Akos Varga-Szemes; Tilman Emrich; Dmitrij Kravchenko

doi:10.1016/j.acra.2024.11.055

Intra-individual Differences in Pericoronary Fat Attenuation Index Measurements Between Photon-counting and Energy-integrating Detector Computed Tomography

Acad Radiol. 2024 Dec 10:S1076-6332(24)00931-0. doi: 10.1016/j.acra.2024.11.055. Online ahead of print.

Authors

Affiliations

¹ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Department of Medical Surgical Sciences and Translational Medicine, Sapienza University of Rome - Radiology Unit - Sant'Andrea University Hospital, Via di Grottarossa, 1035-1039, 00189 Rome, Italy (G.T.).
² Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Heart and Vascular Centre, Semmelweis University, Budapest, Hungary (M.V-N.).
³ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Department of Diagnostic and Interventional Radiology, Medical Center, Faculty of Medicine, University of Freiburg, University of Freiburg, Hugstetter Straße 55, Freiburg im Breisgau 79106, Germany (M.T.H.).
⁴ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.).
⁵ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Siemens Medical Solutions USA Inc, Malvern, PA (J.O.).
⁶ Department of Diagnostic and Interventional Radiology, University Hospital Bonn, Bonn, Germany (J.A.L., D.Ku., A.I., D.K.); Quantitative Imaging Laboratory Bonn (QILaB), Bonn, Germany (J.A.L., D.Ku., A.I., D.K.).
⁷ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.). Electronic address: [email protected].
⁸ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Department of Diagnostic and Interventional Radiology, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany (T.E.); German Centre for Cardiovascular Research, Partner site Rhine-Main, Mainz, Germany (T.E.).
⁹ Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (G.T., M.V-N., M.T.H., J.O., A.V-S., T.E., D.K.); Department of Diagnostic and Interventional Radiology, University Hospital Bonn, Bonn, Germany (J.A.L., D.Ku., A.I., D.K.); Quantitative Imaging Laboratory Bonn (QILaB), Bonn, Germany (J.A.L., D.Ku., A.I., D.K.).

PMID: 39665893
DOI: 10.1016/j.acra.2024.11.055

Abstract

Rationale and objectives: The purpose of this study was to explore intra-individual differences in pericoronary adipose tissue (PCAT) fat attenuation index (FAI) between photon-counting detector (PCD)- and energy-integrating detector (EID)-CT.

Material and methods: Patients were prospectively enrolled for a PCD-CT research scan within 30 days of EID-CT. Both acquisitions were reconstructed using a Qr36 kernel at 0.6 mm slice thickness (EID and PCD-down-sampled [DS]) and at 0.2 mm ultra-high resolution (UHR) for the PCD-CT. Iterative reconstruction was turned "off" (filter back projection used as alternative reconstruction method) or set to a recommended level in current literature. Coronary PCAT FAI was measured automatically using established thresholds of -190 to -30 HU at a set distance and radius. Statistical testing was performed using repeated-measures ANOVA and Bonferroni's multiple comparison tests (p significance was determined to be <0.003).

Results: In total, 40 patients (mean age 68±8 years, 32 males [80%]) were included for analysis. Absolute FAI measurements differed significantly for all vessels between all reconstructions in the ANOVA comparison (all p<.001). The FAI decreased going from EID-CT to PCD-DS, to PCD-UHR with iterative reconstruction turned off (e.g. right coronary artery: EID-CT: -76.5±8.9 vs -80.9±7.0 vs -88.3±6.7 HU, respectively; p < 0.001). The mean FAI of datasets using iterative reconstruction did not demonstrate significant differences on multiple comparisons (e.g. left circumflex artery: EID: -65.7±8.5; PCD-DS: -66.0±7.4; PCD-UHR: -67.8±7.0 HU, respectively; p>0.06).

Conclusion: Intra-individual absolute PCAT FAI measurements differ significantly between EID- and PCD-CT when controlling for reconstruction kernel and slice thickness. However, the use of iterative reconstruction minimizes most differences in FAI, enabling inter-scanner comparability.

Keywords: Energy-integrating detector CT; Pericoronary adipose tissue; Photon-counting detector CT.