Abstract Introduction Rounded atelectasis (RA) is an atypical form of focal lung collapse that typically occurs adjacent to thickened pleura. It usually remains stable, or in some cases, may completely resolve. RA is clinically important because it can mimic pulmonary malignancy, leading to unnecessary interventions. It is most commonly described in association with asbestosis-related pleural thickening. However, other causes such as chronic congestive heart failure, healed empyema, complicated hepatic hydrothorax, or cardiothoracic surgeries have also been reported. We present a case of RA in a patient with hepatic hydrothorax complicated by spontaneous bacterial peritonitis. Case Summary A 52-year-old male with a history of decompensated alcoholic cirrhosis, complicated by frequent admissions for hepatic encephalopathy and abdominal ascites, was admitted for spontaneous bacterial peritonitis. Chest x-ray revealed a right-sided pleural effusion. The patient had a persistent right-sided pleural effusion for over 1.5 years, with previous thoracentesis revealing transudative fluid. CT chest imaging showed new 4.5 cm and 5 cm rounded to oval masses in the right lower lung, adjacent to pleural thickening. The masses had acute angles and contained air. A linear opacity extending to the inferior aspect of the masses, representing converging bronchovascular structures, was also noted. The masses had not changed over six months, while the pleural fluid had resolved. The patient was diagnosed with rounded atelectasis and no further work up was recommended. Discussion RA results from pleural fibrosis, which causes contraction of pleura and subsequent invagination into the adjacent lung parenchyma. This process leads to the trapping of affected lung tissue, which can resemble a mass due to its rounded shape. RA is recognized based on characteristic CT imaging findings. Key features include a rounded to oval shape, adjacent pleural thickening with converging bronchovascular markings which is also known as the comet-tail sign, and air bronchograms within the lesion. Radiological recognition of RA is important to prevent unnecessary invasive intervention. While asbestosis-related pleural thickening is the most common association with RA, it may arise related to other disorders including complicated hepatic hydrothorax as we described in our patient. This abstract is funded by: None
Kocak et al. (Fri,) studied this question.