The mediastinum is the space present between the lungs. Abnormal growth of lymph nodes or other tissue in this region may be investigated by performing a biopsy. A biopsy is the process of obtaining a sample of tissue for laboratory examination. Mediastinal masses or lymph nodes may be biopsied with the help of a biopsy needle or a lighted tube called a mediastinoscope.
A mediastinal biopsy is performed to evaluate the spread of cancer, presence of infections such as tuberculosis and certain autoimmune conditions. It can help identify conditions such as lymphoma, Hodgkin disease, sarcoidosis and lung cancer.
Before the procedure, your doctor will review your history and advise you about any alteration in medication. You will also be instructed when to stop eating or drinking before the procedure.
A needle biopsy is performed under sedation and local anaesthesia. The area in question is located with the help of a CT scan, MRI or ultrasound and the skin over the area is marked. The surrounding area is then cleansed and numbed. The biopsy needle is then inserted through this region and guided with imaging studies to the correct location. After adequate tissue samples are obtained, the needle is removed and the area is covered with a bandage. You may experience some discomfort during the procedure. Following the procedure, you may cough up some blood. Rarely, lung collapse can occur requiring intervention.
A mediastinoscopy with biopsy is performed under general anaesthesia. An endotracheal tube is first inserted through your mouth or nose to help you breathe. A small incision is made in your neck and the mediastinoscope is passed through until it reaches the mediastinum in the middle of the chest. The area is carefully viewed and tissue samples obtained with instruments through the tube. The mediastinoscope is then withdrawn and the incision closed with sutures. The entire procedure may take 60 to 90 minutes. You may experience some tenderness at the site or a sore throat following the procedure which resolves on its own.