Comparison of chest radiography and chest CT for evaluation of pediatric COVID-19 pneumonia: Does CT add diagnostic value?

Abstract

Purpose: First, to investigate the added diagnostic value of chest computed tomography (CT) for evaluating COVID-19 in symptomatic children by comparing chest CT findings with chest radiographic findings, and second, to identify the imaging signs and patterns on CT associated with COVID-19 pneumonia in children.

Materials and methods: From March 2020 to December 2020, 56 consecutive children (33 males and 23 girls; mean age ± SD, 14.8 ± 5.0 years; range, 9 months-18 years) with mild to moderate symptom and laboratory confirmed COVID-19 (based on Centers for Disease Control criteria) underwent both chest radiography and chest CT on the same day within the first 2 days of initial presentation to the hospital. Two experienced radiologists independently evaluated chest radiographs and chest CT studies for thoracic abnormalities. The findings from chest radiography and chest CT were compared to evaluate the added diagnostic value of chest CT for affecting patient management. Interobserver agreement was measured with Cohen's κ statistics.

Results: Eleven (19.6%) of 56 patients had abnormal chest radiographic findings, including ground-glass opacity (GGO) in 5/11 (45.4%) and combined GGO and consolidation in 6/11 (54.5%). On chest CT, 26 (46.4%) of 56 patients had abnormal CT findings, including combined GGO and consolidation in 19/26 (73.1%), GGO in 6/26 (23.1%), and consolidation in 1/26 (3.8%). Chest CT detected all thoracic abnormalities seen on chest radiography in 11/26 (42.3%) cases. In 15/26 (57.7%), chest CT detected lung abnormalities that were not observed on chest radiography, which included GGO and consolidation in 9/15 (60%), GGO in 5/15 (33.3%), and consolidation in 1/15 (6.6%) cases. These additional CT findings did not affect patient management. In addition, chest CT detected radiological signs and patterns, including the halo sign, reversed halo sign, crazy paving pattern, and tree-in-bud pattern. There was almost perfect interobserver agreement between the two reviewers for detecting findings on both chest radiographs (κ, 0.89, p = .001) and chest CT (κ, 0.96, p = .001) studies.

Conclusion: Chest CT detected lung abnormalities, including GGO and/or consolidation, that were not observed on chest radiography in more than half of symptomatic pediatric patients with COVID-19 pneumonia. However, these additional CT findings did not affect patient management. Therefore, CT is not clinically indicated for the initial evaluation of mild to moderately symptomatic pediatric patients with COVID-19 pneumonia.

Keywords: COVID-19 pneumonia; children; computed tomography; pediatric patients; radiography.

Figure 1

A 16‐year‐old female with positive COVID‐19 RT‐PCR test who presented with fever and cough. (A) Frontal chest radiograph shows multifocal ground‐glass opacities and consolidations (arrows) in both lungs. (B) Coronal lung window CT image demonstrates bilateral multifocal ground‐glass opacities and consolidation (arrows) corresponding with findings seen on chest radiograph (A). CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction

Figure 2

A 15‐year‐old male with positive COVID‐19 RT‐PCR test who presented with fever and chest pain. (A) Frontal chest radiograph shows clear lungs without radiographic abnormality. (B) Axial lung window CT image shows focal small areas of consolidation and subtle ground‐glass opacities (arrows) in the bilateral lower lobes, which were not detected on chest radiography. CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction

Figure 3

A 12‐year‐old male with positive COVID‐19 RT‐PCR test who presented with cough. Axial lung window CT image shows a ground‐glass opacity (arrows) surrounding a central area of consolidation, in keeping with the “halo” sign. CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction

Figure 4

A 16‐year‐old female with positive COVID‐19 RT‐PCR test who presented with fever and rhinorrhea. Axial lung window CT image shows presence of central ground‐glass opacity (asterisk) surrounded by ring of denser consolidation (arrows), also known as the “reversed halo” sign. CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction

Figure 5

A 17‐year‐old female with positive COVID‐19 RT‐PCR test who presented with fever and cough. Axial lung window CT image shows areas of thickened interlobular septa and intralobular lines (arrows) superimposed on a background of ground‐glass opacity (arrowheads) in the left lower lobe, also known as crazy‐paving pattern. CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction

Figure 6

A 15‐year‐old male with positive COVID‐19 RT‐PCR test who presented with cough and dyspnea. Axial lung window CT image shows multiple small centrilobular nodules with connection to opacified or thickened branching structure representing the dilated and opacified bronchioles or inflamed arterioles, also known as tree‐in‐bud pattern. CT, computed tomography; RT‐PCR, reverse‐transcription polymerase chain reaction