Other studies in HRCT findings
is an important component in the diagnostic procedure for patients with
suspected COVID-19 infection. Chest CT has limited sensitivity and
negative predictive value early after symptom onset, and has little
weakness in diagnosis of COVID-19 combined to personal history, clinical
symptoms, and initial laboratory findings, and may therefore serve as a
standard method for diagnosis of COVID-19 based on its features and
transformation rule, the limited number of RT- kits in some centers
before initial RT- screening (Bernheim et al., 2020, Chen et al., 2020).
Although 12% of patients were without abnormal lung changes on initial
CT images in present study.
In a study, the most HRCT findings were bilateral parenchymal
ground-glass opacities, without or with consolidation in the lung
periphery. Especially, 75% patients with
chest HRCT findings related to
COVID-19 pneumonia had negative results of concurrent nucleic acid tests
(He et al., 2020). Then, 21.70%
of positive chest HRCT patients in present study had normal CRP.
According to imaging examination in a study, 75% patients showed
bilateral pneumonia, 14% patients showed multiple mottling and
ground-glass opacity, and 1% patient had pneumothorax
(Chen et al., 2020).
In a study, The CRP, ESR, and LDH
presented significantly positive
correlation with the pneumonia severity on CT. The highest temperature
and the severity of opacifications assessed on initial CT were
significantly related to the progression of opacifications on follow-up
CT(Xiong et al., 2020). In present study, LDH had significantly positive
correlation with HRCT. In a study, GGO was the most common manifestation
of COVID-19 pneumonia, which could be followed by consolidation and
fibrosis.Total CT score, GGO score and fibrosis score of male patients
were significantly higher than female in the second week. Male patients
had higher consolidation score and fibrosis score than female in the
third week. Total CT score and GGO score had weak to moderate
correlation with arterial blood gas
indices (Shang et al., 2020). In
our study, 42.30% of women and 57.70% of men had positive HRCT for
COVID- a meta-analysis, 40 studies with 4183 COVID-19 patients, the rate
of positive CT scan in COVID-19 patients was 94.5%. Bilateral lung
involvement, GGO pulse consolidation or reticular, consolidation,
reticular, presence of nodule findings and GGO, in CT scan of COVID-19
pneumonia patients were respectively estimated to be 64.9% , 49.2% ,
30.3% , 17.0% ,16.6%, 94.5% . The lung lesions distribution in
patients with COVID-19 was 70.0% peripheral, 3.9% central, and31.1%
peripheral and central (Karimian and Azami, 2020). In a study, of 1014
patients, 59% had positive RT- results, and 88% had positive chest CT
scans. The sensitivity of chest CT in suggesting COVID-19 based on
positive RT- results was 97%. In patients with negative RT- results,
75% had positive chest CT findings; 48% were categorized as highly
likely cases, with 33% as probable cases. 60% to 93% of cases had
positive CT consistent with COVID-19 prior to the initial positive RT-
results (Ai et al., 2020).
A total of 14 articles including 1115 patients, pure GGO 69%,
consolidation 47% and “air bronchogram sign” 46% were more common
than the atypical lesion of “crazy-paving pattern” 15%. while 67% of
patients showed a predominant peripheral distribution (Wan et al.,
2020). In a study, included 52% men, and the mean age was 49·5 years.
The major pattern of abnormality observed was bilateral 79%, peripheral
54%, and GGO 65%. A weak relevance was between the fibrosis score and
the value of PaO2 and SpO2(Dai et al., 2020). There was a statistically
significant association between level of O2 saturation and HRCT results
in present study. In a study, with median age of 45 , 98% patients had
evidence of abnormal CT compatible with viral pneumonia at baseline
(Fang et al., 2020).
It suggested the critical importance to combine the two methods in the
early stage of the disease to exclude the SARS-CoV-2 infection. These CT
performances of COVID-19 were similar to previous studies. The O2
saturation decreased in patients, which were in consistence with the
alteration of indices in patients with lung involvement. the bilateral
GGO was higher in the present study. Our results support the use of
chest CT for screening for -19 for patients with clinical and laboratory
features compatible with COVID-19 infection(Shi et al., 2020).
Additionally, a positive relevance
was found between the HRCT score, O2 saturation, that was, a patient
with higher CT score tended to have lower O2 saturation.