Fig. 1

Radiological examinations and fiberoptic bronchoscopy were performed on a 49‑year‑old man with a tracheal coal foreign body prior to surgery. a Chest radiograph shows a high‑density nodule (arrows) in the trachea about the level of the 7th cervical vertebra. b, c Chest axial and coronal CT images also reveal this high‑density nodule (arrows) inserted from the trachea into the right thyroid at the same level as seen on the chest radiograph. d Fiberoptic bronchoscopy reveals a black foreign body in the subglottic trachea. The tracheal lumen was mostly blocked and the fiberoptic bronchoscopy failed to pass through the trachea due to its severe stenosis