Thin-section CT findings of thoracolithiasis

To review thin-section CT findings of thoracolithiasis. Thirty-three thin-section CT scans of 9 patients with thoracolithiasis diagnosed between 2008 and 2016 were reviewed for the location, shape, longest diameter, and calcification of each freely mobile nodule (thoracolith) and for the presence of coexisting abnormalities. The mean age of 9 patients (5 women) was 65.8 years (SD 14.9; range 37-83 years). Eight were > 50 years of age. Three patients had two thoracoliths, and the remaining 6 patients had one. Thoracoliths were in the left (n = 9) or right (n = 3) pleural cavity, with most in the lower pleural cavity. Nine thoracoliths were found to be larger at follow-up. The median diameters of the 12 thoracoliths were 4.9 mm (range 2.1-10.6 mm) and 6.2 mm (range 3.6-11.0 mm) on the initial and latest follow-up CT scans, respectively. Concomitant old granulomatous disease (n = 6) and diffuse systemic sclerosis-related interstitial lung disease (n = 2) were noted. Thoracolithiasis can manifest as one or two small calcified nodules. It tends to occur in the left lower pleural cavity, occur in a patient aged > 50 years, be larger on follow-up, and coincide with other diseases.