Preoperative computerized tomography screening for COVID-19 pneumonia in asymptomatic patients: experiences from two centers

Abstract

Purpose The aim of this retrospective study is to evaluate the preoperative screening performance of chest CT (computerized tomography) examination to detect COVID-19 positive individuals. Materials and methods In this retrospective study 218 adult patients who had preoperative chest CT and RT-PCR were enrolled. CT imaging results, which have been reported according to the Radiological Society of North America expert consensus on COVID-19, were collected from the picture archiving and communicating system. Demographic data, planned surgeries, and postoperative outcomes were collected from the electronic patient records. Results One patient (0.5%) showed typical CT features for COVID-19 pneumonia; 12 patients (5.5%) were reported as indeterminate, and eight (3.7%) were reported as atypical for COVID-19 pneumonia. Only one of the three patients with positive RT-PCR had abnormalities on CT. When RT-PCR tests were taken as reference, the sensitivity, specificity, and accuracy of chest CT in showing COVID-19 infection in asymptomatic patients were 33.3%, 90.7%, and 90.0%, respectively. Conclusion Chest CT screening for COVID-19 has a very low yield in asymptomatic preoperative patients and shows false-positive findings in 9.2% of cases, potentially leading to unnecessary postponing of the surgery.

Clinical significance of chest CT for the exclusion of COVID-19 in pre-admission screening: Is it worthwhile using chest CT with reverse-transcription polymerase chain reaction test?

“…In this study, we compared the diagnostic efficacy of chest CT for screening in asymptomatic patients between the low-prevalence and high-prevalence periods of the pandemic. Our findings indicated that the PPV was 4% in the low-prevalence period and 14.3% in the high-prevalence period, in accordance with values reported in previous studies [ 4 , 13 ].…”

“…In this study, the incidence of chest CT findings leading to suspected COVID-19 pneumonia in asymptomatic pre-hospital patients was 1.8%. These results were much lower than those reported in similar studies that targeted pre-operative asymptomatic patients (7–9.6%) [ 13 , 14 , 17 ].…”

“…However, the incidence of normal chest CT findings in asymptomatic patients with COVID-19 is considerably high (estimated 46%) [ 10 ], and chest CT findings are often normal in the early stage of the disease (i.e., the first 4 to 5 days after the onset of symptoms), even in symptomatic cases (13.9–33.3%) [ 3 , 11 ]. Based on these factors, chest CT is currently not recommended as a routine screening tool for COVID-19, especially in asymptomatic patients [ 3 , [12] , [13] , [14] ].…”

“…We hypothesized that the high sensitivity of the chest CT would balance the limitations of the RT-PCR test and that we would be able to screen asymptomatic patients with COVID-19 who clear a single RT-PCR test. To the best of our knowledge, only a few studies had investigated the utility of chest CT as a screening method for the detection of COVID-19 in asymptomatic patients [ 13 , 14 , 17 ]; however, none have compared the utility of chest CT for COVID-19 screening in asymptomatic patients between the low-prevalence and high-prevalence periods at the same institution. Therefore, the objectives of this study were: (1) to investigate the utility of chest CT as a screening method for the detection of COVID-19 in asymptomatic patients; (2) to investigate whether the diagnostic performance of chest CT in detecting COVID-19 in asymptomatic patients changes according to the prevalence of COVID-19; and (3) to investigate the frequency of incidental chest CT findings that mimic COVID-19 pneumonia.…”

Meta-analysis of COVID-19 prevalence during preoperative COVID-19 screening in asymptomatic patients

“…All studies presented a COVID-19 screening method of either chest CT, symptom screening and RT-PCR or symptom screening and RT-PCR. 32–58 Symptom screening with RT-PCR as the reference test was performed in 22 studies. 34–41 43 45–50 53–59 Symptom screening with chest CT and RT-PCR as the reference test was performed in five studies.…”