The Comparison of EBUS-TBNA, TBMC Via a Tunnel, and TBFB Via a Tunnel in Diagnosing Mediastinal Lymphadenopathy.

A 22G biopsy needle was insert into the lesion through tracheal-bronchial wall under real-time EBUS guided by bronchoscopist. Needle punctures were performed by using the jabbing method. Once it is confirmed that the puncture needle is within the target lesion, the puncture needle is moved back and forth while suction (An empty 50 ml syringe was connected to the port at the end of the puncture needle and aspirated to 20 ml maintained for 20 seconds.) is applied. Each lymph node was operated 5 times.

First a tunnel between airway wall and mediastinal and/or hilar lesion was made by a puncture dilation catheter (BroncTruTM AK-91-55, Bronchus Inc. Hangzhou, China). The 1.1mm cryoprobe (Erbe 20402-401, ERBE, Tübingen, Germany) entered the target lymph node through the tunnel under direct monitoring of EBUS, and the distance between the tip of the cryoprobe and the border of target lymph node was measured using EBUS. After confirming that the distance was \>5 mm, the probe was cooled with liquid carbon dioxide for 5-9 seconds. Then retracted with the bronchoscope and the frozen biopsy tissue. Samples were retrieved by thawing in saline and then fixed in formalin. The same lymph node was operated for 3 times.

Firstly, a tunnel to reach the lymph node is established by making use of a puncture dilation catheter, and a 1.5mm biopsy forceps is pushed into the lymph node through the working channel of the ultrasound bronchoscope. After entering the lymph node, the biopsy forceps were opened proximally to the lymph node, the biopsy forceps were advanced, and then the biopsy forceps were closed distally to the lymph node for each specimen. Each lymph node was operated 5 times.