Thoracolithiasis: 11 cases with a calcified intrapleural loose body

To describe clinical and imaging characteristics of thoracolithiasis.

Medical records from our center from September 2005 to March 2007 were reviewed. A definitive diagnosis was made by multidetector-row computed tomography studies of the chest, which revealed in each patient an intrapleural calcified nodular opacity, which changed in intrapleural location on serial examinations. Eleven patients fulfilled this criteria. The images were analyzed by experienced radiologists, who focused on the distribution, size, and shape of the thoracolithiasis.

The incidence of thoracolithiasis was 0.086% (11 of 12,835 individuals). All the patients were asymptomatic and did not have any history of intrathoracic disease. The nodules ranged in size from 5 to 15 mm (median 8 mm), and were ovoid and smoothly marginated. Each nodule contained homogeneous diffuse calcification. Eight nodules occurred in the left pleural space and 3 in the right. Their locations varied, which included on the diaphragm, along the posterior chest wall of the lower lung, abutting the left cardiac margin, and near the paraspinal space of the lower thoracic spine. Each of the calcified pleural bodies changed in intrapleural location on follow-up computed tomography examination.

The calcified intrapleural nodular opacities of thoracolithiasis tended to be located inferiorly, presumably secondary to the effects of gravity, and they seemed to migrate freely within the pleural cavity.