Radiological evaluation
Computed Tomography images were reretrospectively re-evaluated by 3
radiologists. Typical and atypical chest CT findings related to Covid 19
pneumonia were evaluated separately by each radiologist blinded to the
previously written reports. Multifocal ground glass opacities (GGO),
consolidation, GGO with superimposed consolidation, consolidation
predominant pattern, crazy paving pattern, and melted sugar sign were
considered as typical; pleural and/or pericardial effusion, cavity,
pulmonary nodule, nodular pattern, lymphadenopathy, peribronchovascular
distribution, halo and/or reverse halo sign, three-in-bud sign,
bronchiectasis, airway secretions, pulmonary emphysema, pulmonary
fibrosis, isolated pleural thickening, and pneumothorax were considered
as atypical findings for covid pneumonia.(6) Patients were categorised
as “normal”, “typical for covid”, “atypical for covid” and “not
covid” similarly with the previous structured reports. Afterwards,
parenchymal involvement ratios were visually defined for “typical for
covid” and “atypical for covid” groups; <25%, 26-50%,
51-75%, and 76-100%. In case of a conflict between evaluations, the
decision was made with the consensus of three radiologists. In addition
to this re-evaluation, a forth radiologist searched for preliminary
reports, final reports and radiology consultation notes of these
patients. The point of this thoughtful research is to find out the very
first on-call radiologist’s comment on CT images.
Results of the re-evaluation were compared with previously written
reports and also with PCR test results. By this way, the diagnostic
accuracy of CT reports was aimed to be determined throughout the whole
process from the first stage of the epidemic to the present.