The crisis of Coronavirus disease 2019 (COVID-19) has recently attracted the attention all over the world. (COVID-19), is a highly infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [6].
Currently, there are no validated anti-viral medications or other specific therapies targeted toward the treatment of COVID-19. Management of this disease is symptomatic and, more importantly, focused on public health measures which slow the spread of disease, an epidemiological concept referred to as “flattening the curve” [7].
Therefore, early recognition of patients with COVID-19 (radiologic or otherwise) is critical in order to isolate these cases and prevent additional infection [8].
Computed tomography (CT) is an important and essential method for the diagnosis and evaluation of the severity of COVID-19 as well as monitoring disease progression and evaluating the therapeutic efficiency [9].
Quantitative imaging analysis (QIA), which allows for precise identification of lung tissue density by Hounsfield units (HU), can help differentiate otherwise subtle radiographic diagnoses (Fig. 1) [10].
This cross section study included 30 patients (21 males, 9 females) with male predominance 70%. Age range from 25 to 65 years (mean age of 34.2 years). All patients confirmed to be infected with SARS-CoV-2 using RT-PCR test.
MSCT of the chest was done to all patients as requested & the acquired images were sent to a separate workstation using certain DICOM viewer to be processed & manipulated.
The study was conducted between first of May and July 12, 2020, in Cairo, Egypt.
The interval from onset symptoms to first chest CT scan was 6–8 days. The common first symptoms were fever seen in 23 patients ( 77.4%), dry cough in 18 patients ( 60%), while 10 patients ( 33.3%) presented with dyspnea which agrees with study done by Dong Sun, et al. [11].
In our study we noted, ground-glass opacity (GGO) is the main CT findings in patients with mild/early COVID-19 and was seen in 26 patients (86.6%) & it was essentially associated with the course and severity of the disease which agrees with the study done by and Feng Z et al. [12].
The detection and recognition of GGO is based on a subjective assessment of lung attenuation at CT, therefore, CT should be performed within objective parameters that make lesion depiction reliable and reproducible (Fig. 2) [13].
GGOs may not always be obvious on CT images, and they may be missed. The recognition of GGO is based on a subjective assessment of lung attenuation at CT (Fig. 3) [14].
In the present study, ground glass opacity seen in 26 patients (86.6%) were detected by both visual and color coded images, while in 4 patients (13.3%) the GGO were very faint and were only visualized by color coded images and confirmed by CT density assessment (Fig. 4).
The size of the lesions ranged in diameter from 1 cm–3 cm. and that goes with study of Dong Sun, et al. that showed correlation between size of lesion and severity of symptoms [11].
The early identification of patients and assessment of the severity of COVID-19 may guide clinical treatment options and reduce the mortality rate. In the present study, a using both visual and color coded images helped in confirming diagnosis of mild/early cases of COVID-19 and that was confirmed by study done by Dong Sun,et al. (Fig. 5) [11].
In summary, this study revealed that the combined use of visual and color coded images enhance and improve the early detection of faint ground glass opacities seen in early COVID-19 affection which could help in improving the disease prognosis as well as limiting spread of this highly contagious disease.