COVID-19 pneumonia manifestations at the admission on chest ultrasound, radiographs, and CT: single-center study and comprehensive radiologic literature review

Abstract

Purpose: To investigate the imaging features of emerging COVID-19 pneumonia on chest ultrasound (US), radiographs (CXR) and computed tomography (CT) examinations performed at admission and to provide a comprehensive radiological literature review on ongoing radiological data from recent publications.

Materials and methods: In this retrospective single-center study, we enrolled consecutive patients from February 15, 2020, to March 15, 2020, with laboratory-confirmed SARS-CoV-2 hospitalized in Valduce Hospital (Como, Italy). Multi-modality imaging findings were evaluated and compared. Literature research was conducted through a methodical search on Pubmed and Embase databases.

Results: Fifty-eight patients (36 men, 22 women; age range, 18-98 years) were included in the study. Among these, chest US, CXR, and CT were performed respectively in twenty-two, thirty-two and forty-two patients. Lung US findings were consistent with diffuse B lines (100%) and subpleural consolidations (27.3%). CXR showed prevalent manifestations of consolidations (46.9%) and hazy increased opacities (37.5%). Typical CT features included bilateral and multilobar ground-glass opacities (GGO) with (59.5%) and without (35.7%) consolidations having a predominantly peripheral distribution (64.3%). Other imaging features included crazy paving pattern (57.1%), fibrous stripes (50%), subpleural lines (35.7%), architectural distortion (28.6%), air bronchogram sign (26.2%), vascular thickening (23.8%) and nodules (2.4%). Also, enlarged lymph nodes (14.3 %) and pleural effusion (7.1%) were observed. The literature review identified twenty-six original studies supporting our imaging chest findings.

Conclusion: The spectrum of chest imaging manifestations of COVID-19 pneumonia upon admission includes B-lines and consolidations on US, consolidations and hazy increased opacities on CXR, and multifocal GGO with consolidations on CT.

Keywords: COVID-19; Computed Tomography (CT); SARS-CoV-2; coronavirus disease; pneumonia; radiographic chest examination (CXR); ultrasound (US).

Fig. 1

Ultrasound evaluation of lung parenchyma using the convex transducer in a patient with Coronavirus disease-19 (A) shows the simultaneous co-existence of multiple lung B-lines and A-lines. Chest x-ray (B) shows bilateral lung opacities which appear more evident in the peripheral areas.

Fig. 2

Ultrasound lung evaluation using a convex and linear transducer (A) of a patient with Coronavirus disease-19 shows compact B-line without horizontal reverberation (white lung sign), with tiny areas of subpleural consolidation. Axial CT evaluation of the same region shows bilateral and diffuse ground-glass opacities (B). Coronal and sagittal chest CT images (C and D) also demonstrate the diffuse extension of these findings.

Fig. 3

Ultrasound thoracic examination using a linear transducer of a Patient with Coronavirus disease-19 (A) shows the irregular appearance of the pleural line with multifocal B-line. Axial CT image of the same region shows patchy bilateral ground-glass opacities and consolidations (B) with air bronchogram (arrow in B).

Fig. 4

18-year-old female with a fever and cough for 7 days non-responsive to antibiotic therapy, without other known comorbidities neither relatives with similar symptoms. Chest x-ray shows bilateral opacities mainly peripheral and more evident in the left lung. Axial chest CT shows peripheral ground-glass opacities in the right upper lobe and consolidation in the left upper lobe (B). These findings are more evident in the lower lobes (C), especially in the left lower lobe, which appears almost completely consolidated. Air bronchogram sign is also evident (arrows in C). Diagnosis of Coronavirus disease-19 with the atypical presentation was confirmed with an oropharyngeal swab.

Fig. 5

A 67-year-old male with a history of fever for 12 days. An oropharyngeal swab performed a couple of days after the onset of symptoms was negative for Coronavirus disease-19. He was hospitalized for the persistence of symptoms and the onset of dyspnea. Axial chest CT images show patchy bilateral ground-glass opacities in the upper lobes mainly peripheral (A and B) and more consolidated areas along with ground glass opacities in the lower lobes (C). A new oropharyngeal swab confirmed Coronavirus disease-19. A follow-up CT performed 8 days after his hospitalization shows consolidation of the involved lung parenchyma. Air bronchogram sign is also evident (arrow in E).

Fig. 6

61-year-old female with a history of fever, cough and mild pharyngodynia for 2 days. Axial chest CT images show ground-glass opacities (arrows, A and B). Coronal CT image clearly shows the thickness of interlobular and intralobular septa, “crazy paving” (arrow, C). Coronavirus disease-19 was confirmed on the oropharyngeal swab.

Fig. 7

Axial CT image shows fibrous stripes in the right lower lobe (arrow, A). Axial CT scan shows subpleural lines in bilateral lower lobes (arrow, B).

Fig. 8

Coronal and Axial Minimum-intensity-projection CT images show bronchus architectural distortion (arrows, A and B).

Fig. 9

Axial chest CT images of four different patients with confirmed coronavirus disease-19 show ground-glass opacities with perilesional vascular thickening (arrows in A-D).