Fig. 1

Tracheal agenesis—Case 1: Ventral view of the respiratory tract showing defect of the entire trachea except for a cartilage-free sublaryngeal pouch (P), with fused main bronchi (B), connected to the oesophagus (O) by a broncho-oesophageal fistula (BOF—TAG Floyd type 2) and with bilaterally bilobed lungs. Transversal section plane (H&E, 2,5) of the oesophagus with normally structured wall and without any tracheal components on histology (inlay) (a). Case 3: Ventral view of the respiratory tract with an absent trachea, sublaryngeal pouch (P), bilaterally bilobed lungs and a BOF connecting the fused right main bronchus (B) and left lower lobe bronchus with the oesophagus (O) and a second separate BOF connecting the left upper lobe brtonchus with the oesophnagus. Dorsal view of the opened oesophagus (O) and BOFs (inlay) (b). Case 2: Post-mortem MRI, axial T2 weighted image (T2WI) showing aorta (white arrows), vena cava superior (VCS) (blue arrow), oesophagus (green arrow) and lack of a trachea (c). Dorsal view of the internal surface of the oesophagus showing the opening to the BEF of only 1.5 mm in diameter (yellow arrow) (d). Case 4: View of the opened larynx from dorsal with the oesophagus (O) laid aside showing hypoplasia of the epiglottis and the tracheal pouch (P) dorsally opened (e). Case 5: Dorsal view of the larynx with a hypoplastic epiglottis, an intact position of the oesophageus (O) and a tracheal pouch (P) behind (f)