A Protocol of Low Dose Chest CT to Verify Suspected COVID -19 infection

Abstract

Chest CT scanning is significant in verifying COVID-19 infection in patients with clinical symptoms,
although CT scanning uses ionizing radiation. So we aim to investigate the demonstration of relevance and
accuracy of chest tomography using a low-dose protocol compared to the standard auto-modulation protocol
of 50 – 210 mAs. Moreover, to assess whether any distinguishing signs in patients might help determine
the severity of the respiratory infection from COVID-19. A standard auto-modulation protocol of 50 – 210
mAs was performed for all patients (120 patients), Rotation time 0.5 second. Of the 120 patients whose
CT scan showed signs of COVID-19 infection, 47 patients aged over 50 years were selected. Low dose
CT scanning (30 mAs) was performed on these patients immediately. Of the 120 patients over the age of
50 with COVID-19 according to a PCR underwent a CT chest, only 47 showed signs of COVID-19.When
compared to standard-dose, low-dose demonstrated excellent sensitivity in detecting typical findings of
COVID-19 (coefficient of significance (C.S) = 0.98–0.99, P-values < 0.05 one reader and P-values < 0.01
two readers). The mean effective dose values were 6.32±2.82 and 1.45±0.29mSvin the stander and lowdose,
respectively.A low dose protocol can be used with high reliability and accuracy to reduce the ionizing
radiation risks in the state of reproducible assessment. On the other hand, we emphasize there are indicators
with high reliability of a relationship between infection with COVID-19 and its severity and the work nature,
environment, age, body mass index (BMI) and Patient Health Status.