Purpose: To explore the CT findings in patients with covid 19 and find cases of incidentaloma.

Method: In this retrospective comparative study, a total of 15874 patients with COVID-19 were included: 1281 patients with wild type (748 men, 52.6 years), 7945 with Alpha variant (4972 men, 46.2), 4233 with Delta variant (2548 men) and 2415 with Omicron and subtypes (1301 man, 44.2). Chest CT evaluation included opacities and repairing changes as well as lesion distribution and laterality. Chest CT severity score was also calculated. These parameters were statistically compared across the variants. Accidental finding underwent CT examination after covid 19.

Results: Total of 15874 patients with confirmed covid 19 underwent CT examination. There were 511 patients with micronodule changes with at least one micronodule larger then 4 mm suspicion to non-covid illness. There were 8 carcinomas of thoracic wall with bone destruction, 3 mediastinal malignoma, 22 earlier undetected tuberculosis, 17 earlier unknown sarcoidosis, 12 patients were with metastatic disease earlier unknown. From 511 with micronodules malignoma were confirmed in 47 cases, 117 were unclear and went to follow-up. Others were with benign formations or without any nodule. 17 patients finished lethal with possibility of malignoma, but not confirmed. There were no significant differences between the different strains. Exacerbation of earlier confirmed malignoma were also detected. Histologically there were 24% of small cells lung carcinoma.

Conclusions: Incidentaloma can be found during epidemic with pneumonia, ground glass, crazy paving, consolidation. It is important to follow any unclear finding.