A gastroscopy is a procedure performed under light sedation in hospital to investigate and diagnose several problems involving the upper gastrointestinal tract (oesophagus, stomach, first part of small bowel). It is performed using an instrument called a gastroscope which is a flexible tube camera that is about the thickness of a finger. It is inserted via the mouth and allows the surgeon to carefully examine the lining of oesophagus, stomach and first part of the small bowel. Any abnormalities may be sampled (biopsied) and examined in the laboratory to assist with diagnosis. Possible procedures performed in a gastroscopy may include a biopsy, poylpectomy, bleeding intervention.