Bronchoscopy is a procedure used to directly visualize the inside of the lungs. It employs a bronchoscope, a long, flexible tube with a light and camera at the end. Specially designed surgical instruments can be inserted through the bronchoscope to perform procedures inside the lungs. During bronchoscopy, the patient is heavily sedated or under anesthesia and will not experience pain or remember the procedure.

There are multiple types of bronchoscopes. In most cases, a flexible bronchoscope is the preferred option. The flexible bronchoscope can bend easily, reducing the risk of injury to the lungs. Its smaller size also allows it to be inserted into smaller airways.

However, in some cases, a rigid bronchoscope may be used. Unlike the flexible bronchoscope, it cannot bend. The rigid bronchoscope’s larger size enables it to remove larger objects, pieces of tissue, or significant volumes of fluid when necessary. However, it is limited to use in larger airways. Additionally, general anesthesia is required for a rigid bronchoscope, whereas a flexible bronchoscope can be used with sedation instead of full anesthesia.

Bronchoscopy is performed for various reasons, such as removing a foreign object from the airway or diagnosing a lung condition. A common reason for bronchoscopy is to investigate a concerning spot seen on an imaging test (such as an X-ray or CT scan) or to address symptoms like coughing up blood. One goal is often to determine whether the patient has lung cancer—either primary lung cancer or cancer that has spread to the lung from another part of the body.

During a diagnostic bronchoscopy, a biopsy is often performed. This involves taking a small tissue sample to send to a laboratory, where a pathologist examines it under a microscope to determine if it represents cancer or another condition. Biopsies are often taken using needle aspiration, where a syringe and needle gather cells from the target area for testing.

Biopsies may be taken from lung tissue and/or lymph nodes in the area. Since cancer often spreads to lymph nodes, biopsying these nodes is a critical part of cancer staging, which assesses how advanced the cancer is. Enlarged lymph nodes identified on an X-ray or CT scan are often biopsied during bronchoscopy.

Biopsies during bronchoscopy are obtained through the airway wall. If a biopsy is taken through the wall of the trachea (the largest airway), it is called a transtracheal biopsy. If it is taken through the walls of the bronchi (the next set of airways), it is called a transbronchial biopsy. Bronchoscopes cannot reach smaller airways. If a biopsy cannot be taken through the walls of these airways, alternative methods such as needle biopsy through the chest wall or a surgical procedure known as thoracoscopy may be needed.

Other techniques during bronchoscopy can collect cells for analysis. Bronchial brushing involves passing a brush over the airway’s surface to collect cells, which a pathologist then examines to determine if they are cancerous. Another method, bronchial alveolar lavage (BAL)—also known as bronchial washing or cell washing—involves introducing sterile saline (salt water) into an area of the lung. Cells in the area mix with the saline, which is then collected and analyzed. Performing bronchial brushing before BAL helps dislodge cells, making them easier to collect.

In cases where a concerning spot has been identified, the doctor must ensure the correct tissue sample is taken. Guidance tools are used to achieve this and evaluate tissues adjacent to the airways for potential concerns. Methods include endobronchial ultrasound (EBUS), which uses sound waves to visualize tissues outside the airway walls, and fluoroscopy, which uses a continuous X-ray image to assess the patient’s chest.