Presentation
Patient suffering from psoriasis, and chronic myeloid leukemia.
Patient Data
Note: This case has been tagged as "legacy" as it no longer meets image preparation and/or other case publication guidelines.



Left-sided blunting of the costophrenic recess indicating pleural effusion, and a lower lung lobe mass seen posteriorly on an exam that was initially performed to rule out pneumonia.
CT was subsequently performed to further characterize the lesion.



The subpleural left lower lobe lesion shows a profound comet tail sign due to the curled bronchovascular bundles, and resultant pleural effusion. After the administration of iv. contrast a homogeneous enhancement can be observed. Altogether the findings are in line with round atelectasis.
Case Discussion
Differential diagnosis between round atelectasis and lung mass can be difficult. Comet tail sign, together with pleural effusion are suggestive features of round atelectasis.