Correlation Between Chest Computed Tomography and Lung Ultrasonography in Patients With Coronavirus Disease 2019 (Covid-19)

Abstract

INTRODUCTION: There is growing evidence regarding the imaging findings of Coronavirus Disease 2019 (COVID-19), in chest X-ray and Computed Tomography scan (CT). At this moment, the role of Lung Ultrasonography (LUS) has yet to be explored. OBJECTIVES: The main purpose of this study is to evaluate the correlation between LUS findings and chest CT in confirmed (positive RT-PCR) or clinically highly suspicious (dyspnea, fever, myasthenia, gastrointestinal symptoms, dry cough, ageusia or anosmia) of COVID-19 patients. METHODS: Prospective study carried out in the emergency department (ED) of confirmed or clinically highly suspicious COVID-19 patients who were subjected to a chest CT and concurrent LUS exam. An experienced ED physician performed the LUS exam blind to the clinical history and results of the CT scan, which were reviewed by two radiologists in consensus for signs compatible with COVID-19 (bilateral ground-glass opacities in peripheral distribution). Compatible LUS exam was considered a bilateral pattern of B-lines, irregular pleural line and subpleural consolidations. RESULTS: Between March and April 2020, fifty-one patients were consecutively enrolled. The indication for CT was a negative or indeterminate RT-PCR test (49.0%) followed by suspicion of pulmonary embolism (41.2%). Radiological signs compatible with COVID-19 were present in thirty-seven patients (72.5%) on CT scan and forty patients (78.4%) on LUS exam. The presence of LUS findings was correlated with a positive CT scan suggestive of COVID-19 (OR: 13.3, 95%CI: 4.5-39.6, p<0.001) with a sensitivity of 100.0% and a specificity of 78.6%, positive predictive value of 92.5% and negative of 100.0%. There was no missed diagnosis of COVID-19 with LUS compared to CT in our cohort. The LUS Score had a good correlation with CT total severity score (ICC 0.803, 95% CI 0.60-0.90, p<0.001). CONCLUSION: LUS presents similar accuracy compared to chest CT to detect lung abnormalities in COVID-19 patients.

On the Role of Artificial Intelligence in Medical Imaging of COVID-19

“…But others reported relatively low sensitivity (0.69 and 0.78) for mild and moderate cases of COVID-19 [68]. Similar accuracy of LUS and CT was reported in [47], with LUS identifying signs of COVID-19 more likely than CT (78% vs. 72%). This has caused a vivid debate on the role of LUS for the COVID-19 pandemic [48], [49], [69].…”

“…US has received little attention in AI despite its wide, global availability which is a key factor for dealing pandemics, especially in remote and undeveloped areas where supply chains are long, and repurposing of existing technologies is the sharpest weapon for prompt pandemic alleviation. Given that LUS is also more sensitive than CXR [44], comparable to CT [47], and has evident practical advantages, it is presumably the modality with the highest improvement potential for medical image analysis in the near future.…”

“…SARS-CoV-2 induces patterns characteristic for viral pneumonia, most prevalently Blines (vertical, comet-tail artifacts arising from the pleural line [45]) and pleural line abnormalities such as pleural thickening [46]. Findings suggest high diagnostic sensitivity that is comparable to CT scans and can help with diagnosis and subsequent monitoring of the infection [47]. Point-by-point correspondence between LUS and CT patterns can be made and even structured into a disease timeline [24].…”

The utility of lung ultrasound in COVID-19: A systematic scoping review

“…14 LUS specificity may therefore be underestimated in studies where LUS is compared only to RT-PCR. For example, in the work by Bar et al 37 specificity was 62% (vs. RT-PCR) but in Tung-Chen et al 31 specificity was 79% (vs. CT).…”

“…In a single centre study by Tung-Chen et al, 31 51 adults presented to ED with confirmed or suspected COVID-19, both received CT and LUS and 67% were admitted. LUS was performed by a single, experienced operator blinded to CT and clinical findings.…”