Dark-field chest X-ray imaging for the assessment of COVID-19-pneumonia

• Published in: Communications medicine Vol. 2; no. 1; pp. 147 - 9
• Main Authors: Frank, Manuela, Gassert, Florian T., Urban, Theresa, Willer, Konstantin, Noichl, Wolfgang, Schick, Rafael, Schultheiss, Manuel, Viermetz, Manuel, Gleich, Bernhard, De Marco, Fabio, Herzen, Julia, Koehler, Thomas, Engel, Klaus Jürgen, Renger, Bernhard, Gassert, Felix G., Sauter, Andreas, Fingerle, Alexander A., Haller, Bernhard, Makowski, Marcus R., Pfeiffer, Daniela, Pfeiffer, Franz
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 21.11.2022; Springer Nature B.V; Nature Portfolio
• Subjects: 692/308; 692/699; Coronaviruses; COVID-19; Lungs; Medical imaging; Medicine; Medicine & Public Health; Patient assessment; Patients; Pneumonia; X-rays
• ISSN: 2730-664X; 2730-664X
• DOI: 10.1038/s43856-022-00215-3

Background Currently, alternative medical imaging methods for the assessment of pulmonary involvement in patients infected with COVID-19 are sought that combine a higher sensitivity than conventional (attenuation-based) chest radiography with a lower radiation dose than CT imaging. Methods Sixty patients with COVID-19-associated lung changes in a CT scan and 40 subjects without pathologic lung changes visible in the CT scan were included (in total, 100, 59 male, mean age 58 ± 14 years). All patients gave written informed consent. We employed a clinical setup for grating-based dark-field chest radiography, obtaining both a dark-field and a conventional attenuation image in one image acquisition. Attenuation images alone, dark-field images alone, and both displayed simultaneously were assessed for the presence of COVID-19-associated lung changes on a scale from 1 to 6 (1 = surely not, 6 = surely) by four blinded radiologists. Statistical analysis was performed by evaluation of the area under the receiver–operator-characteristics curves (AUC) using Obuchowski’s method with a 0.05 level of significance. Results We show that dark-field imaging has a higher sensitivity for COVID-19-pneumonia than attenuation-based imaging and that the combination of both is superior to one imaging modality alone. Furthermore, a quantitative image analysis shows a significant reduction of dark-field signals for COVID-19-patients. Conclusions Dark-field imaging complements and improves conventional radiography for the visualisation and detection of COVID-19-pneumonia. Plain language summary Computed tomography (CT) imaging uses X-rays to obtain images of the inside of the body. It is used to look at lung damage in patients with COVID-19. However, CT imaging exposes the patient to a considerable amount of radiation. As radiation exposure can lead to the development of cancer, exposure should be minimised. Conventional plain X-ray imaging uses lower amounts of radiation but lacks sensitivity. We used dark-field chest X-ray imaging, which also uses low amounts of radiation, to assess the lungs of patients with COVID-19. Radiologists identified pneumonia in patients more easily from dark-field images than from usual plain X-ray images. We anticipate dark-field X-ray imaging will be useful to follow-up patients suspected of having lung damage. Frank, Gassert et al. use dark-field chest X-ray imaging to assess COVID-19-pneumonia. Dark-field imaging has a higher sensitivity for COVID-19-pneumonia than attenuation-based imaging and provides an ultralow dose alternative to computed tomography imaging for that purpose.