Document Type : Original Paper
Department of Medical Physics, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
Department of Radiology, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
Department of Medical Physics, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
Department of Biostatistics, Kermanshah University of Medical Science, Kermanshah, Iran
Purpose: This study aims to describe chest CT imaging findings and report mortality in two groups of patients with positive and negative initial RT-PCR results regarding the Delta variant.
Material and Methods: In this retrospective study a total of 156 suspected and confirmed patients with COVID-19 who underwent chest CT examinations with both positive and negative initial RT-PCR, were randomly selected. The patients were classified into two groups: 56 patients and 100 patients with negative and positive initial RT-PCR results, respectively.
Results: 156 patients with COVID-19 pneumonia had typical imaging features such as; ground-glass opacities (GGO) (140 [89.7%]), consolidation (33 [21.2%]), vascular enlargement in the lesion (41 [26.3%]). Lesions present on CT images were more likely to have a peripheral distribution (79 [50.6%]), peripheral and central distribution (61 [39.1%]) and architectural distortion (14 [9%]. The other CT features included crazy-paving pattern (25 [16%]), pleural effusion (15 [9.6%]). Only two patients had traction bronchiectasis and tree-in-bud (2 [1.3%]). Otherwise mortality rate in total was (19 [12.2%]). Also, Patients in the group of positive initial RT-PCR had more features such as crazy-paving pattern, peripheral distribution, and GGO compared to the patients in negative initial RT-PCR group.
Conclusions: The most prevalent CT feature was peripheral GGO (140 [89.7%]) in the lungs of patients with COVID-19. The positive initial RT-PCR group had a higher GGO, peripheral distribution, and crazy-paving pattern, in their CT scans than patients in the group with negative initial RT-PCR results. Mortality in groups with initial negative and positive RT-PCR was approximately similar (10.7% and 13%, respectively). It was shown that most of the patients with negative RT-PCR should be considered as a suspect of COVID-19.