Endoscopy
An endoscope is a thin tube instrument with a high intensity light and a camera at the tip. Images are send to a video screen to assist the doctor in navigating the interior of the hollow organ or body cavity.
Gastroscopy
An endoscope is used through the mouth in order to see the stomach, oesophagus, and duodenum.
Colonoscopy
An endosope is used through the anus to see the large bowel allowing the doctor to look for any polyps or cancerous or abnormal growths.