In order to view the interior of the airways for both diagnostic and therapeutic reasons, bronchoscopy is an endoscopic method. The airways are probed using a device called a bronchoscope, often through the nose or mouth but rarely through a tracheostomy. This enables the medical professional to look for anomalies including foreign objects, bleeding, tumours, or inflammation in the patient's airways. It is possible to collect samples from the lungs. Bronchoscopes can be made of stiff metal tubes with lighting fixtures attached or flexible optical fibre instruments with real-time video technology.