Fig. 3.— Artificial widening of the extrapleural space for safe transthoracic needle biopsy (TNB) of mediastinal lesion by an extrapleural approach. A 66-yr-old male presented with dysphagia and altered general condition for since 6 months. Chest radiography showed a middle mediastinal mass. a) Computed tomography (CT) confirms a large mediastinal subcarenal soft tissue mass (arrow). Flexible fibroscopy was unremarkable. Transcarinal needle biopsies were negative. b) CT guided TNB was performed in a prone position. Absence of extrapleural fat prohibits a safe mediastinal access (arrowhead). c) Widening of the extrapleural space was obtained by injection of 50 mL of saline (arrowhead), which displaces the pleura laterally. d) Using a coaxial technique, a small cutting needle was advanced into the lesion through a larger outer needle. Pathology showed poorly differentiated adenocarcinoma.