Fig. 5.

A case of an 85-year-old male patient with a pulmonary nodule. The nodule is located in the left paramediastinal area (danger zone) on the chest radiograph (a). Chest computed tomography revealed a 2.9-cm irregular lobulating contour nodule in his left lower lobe (b). The deep learning-based nodule detection (DLD) system detected this nodule and suggested an abnormality probability of 35% (c). One thoracic radiologist (1/2) and two non-thoracic radiologists (2/2) detected this nodule without the DLD system. Among radiology residents, only one radiology resident detected this nodule (1/4) without the DLD system. Using the DLD system, all the observers were able to detect this nodule