A flexible bronchoscope is longer and thinner than a rigid bronchoscope. Shigeto Ikeda invented the flexible bronchoscope in 1966. Killian used a rigid bronchoscope to remove a pork bone. BLVR valves are placed into the lungs using a catheter through a bronchoscope. To confirm the diagnosis, a doctor may perform a lung biopsy using a bronchoscope. The rigid bronchoscope is a hollow metal tube used for inspecting the lower airway. A flexible bronchoscope is inserted with the patient in a sitting or supine position. Once the bronchoscope is inserted into the upper airway, the vocal cords are inspected. If the bronchoscope is not sterile, saline should initially be used to flush it clean.