Assessment of the new thin convex probe endobronchial ultrasound bronchoscope and the dedicated aspiration needle: a preliminary study in the porcine lung.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) allows for accurate minimally invasive mediastinal lymph node staging of lung cancer. The current convex probe EBUS (CP-EBUS) has limitations in the access to certain N1 lymph nodes (lobar and segmental) because of its size. The aim of this study was to assess the new thin CP-EBUS (TCP-EBUS) and an aspiration needle for sampling of N1 lymph nodes in a porcine model.
METHODS: The prototype TCP-EBUS (BF-Y0046, Olympus Medical Systems Corp.) with a thinner tip (5.9 mm) and larger bending angle (170 degrees upward) was used. Accessibility, operability, and TBNA capability of the TCP-EBUS were assessed and compared with the current CP-EBUS using porcine lungs. The endoscopic visibility range and the maximum reach were evaluated at the left upper lobe bronchus, tracheobronchus, and right lower lobe bronchus. The prototype aspiration needle (Olympus Medical Systems Corp.) was used for EBUS-TBNA.
RESULTS: In all of the evaluated bronchi (n=9), the TCP-EBUS had a greater reach (14.7 mm in the endoscopic visibility range, 16.0 mm in the maximum reach) than the current CP-EBUS. The TCP-EBUS was able to visualize 1 to 3 distal bifurcations farther compared with the current CP-EBUS. Adequate lymph node sampling from lobar and segmental lymph nodes was possible using the aspiration needle.
CONCLUSIONS: The TCP-EBUS has improved accessibility to peripheral bronchi with excellent operability and is capable of sampling lobar and segmental lymph nodes using the dedicated aspiration needle.