Diagnosis of acute pulmonary embolism: when photon-counting-detector CT replaces energy-integrating-detector CT in daily routine

Martine Remy-Jardin; Idir Oufriche; Lucas Guiffault; Alain Duhamel; Thomas Flohr; Bernhard Schmidt; Jacques Remy

doi:10.1007/s00330-024-10724-5

Diagnosis of acute pulmonary embolism: when photon-counting-detector CT replaces energy-integrating-detector CT in daily routine

Eur Radiol. 2024 Apr 18. doi: 10.1007/s00330-024-10724-5. Online ahead of print.

Authors

Martine Remy-Jardin^{1

2

3}, Idir Oufriche⁴, Lucas Guiffault⁴, Alain Duhamel^{5

6}, Thomas Flohr⁷, Bernhard Schmidt⁷, Jacques Remy^{4

8}

Affiliations

¹ ULR 2694 METRICS Evaluation des technologies de santé et des pratiques médicales, Lille, France. dr.remy.jardin@gmail.com.
² IMALLIANCE-Haut-de-France, Valenciennes, France. dr.remy.jardin@gmail.com.
³ Department of Thoracic Imaging, University of Lille, Lille, France. dr.remy.jardin@gmail.com.
⁴ Department of Thoracic Imaging, University of Lille, Lille, France.
⁵ ULR 2694 METRICS Evaluation des technologies de santé et des pratiques médicales, Lille, France.
⁶ Department of Biostatistics, University of Lille, CHU Lille, Lille, France.
⁷ Department of Computed Tomography Research & Development, Siemens Healthineers AG, Forchheim, Germany.
⁸ Department of Radiology, Valenciennes Regional Hospital, Valenciennes, France.

PMID: 38634875
DOI: 10.1007/s00330-024-10724-5

Abstract

Purpose: To compare the diagnostic approach of acute pulmonary embolism (PE) with photon-counting-detector CT (PCD-CT) and energy-integrating-detector CT (EID-CT).

Materials and methods: Two cohorts underwent CT angiographic examinations with EID-CT (Group 1; n = 158) and PCD-CT (Group 2; n = 172), (b) with two options in Group 1, dual energy (Group 1a) or single energy (Group 1b) and a single option in Group 2 (spectral imaging with single source).

Results: In Group 2, all patients benefited from spectral imaging, only accessible to 105 patients (66.5%) in Group 1, with a mean acquisition time significantly shorter (0.9 ± 0.1 s vs 4.0 ± 0 .3 s; p < 0.001) and mean values of CTDI_vol and DLP reduced by 46.3% and 47.7%, respectively. Comparing the quality of 70 keV (Group 2) and averaged (Group 1a) images: (a) the mean attenuation within pulmonary arteries did not differ (p = 0.13); (b) the image noise was significantly higher (p < 0.001) in Group 2 with no difference in subjective image noise (p = 0.29); and (c) 89% of examinations were devoid of artifacts in Group 2 vs 28.6% in Group 1a. The percentage of diagnostic examinations was 95.2% (100/105; Group 1a), 100% (53/53; Group 1b), and 95.3% (164/172; Group 2). There were 4.8% (5/105; Group 1a) and 4.7% (8/172; Group 2) of non-diagnostic examinations, mainly due to the suboptimal quality of vascular opacification with the restoration of a diagnostic image quality on low-energy images.

Conclusion: Compared to EID-CT, morphology and perfusion imaging were available in all patients scanned with PCD-CT, with the radiation dose reduced by 48%.

Clinical relevance statement: PCD-CT enables scanning patients with the advantages of both spectral imaging, including high-quality morphologic imaging and lung perfusion for all patients, and fast scanning-a combination that is not simultaneously accessible with EID-CT while reducing the radiation dose by almost 50%.

Keywords: Acute pulmonary embolism; CT angiography; Energy-integrating-detector CT; Photon-counting-detector CT; Pulmonary arteries.