An abnormality of small blood vessels (microscopically, an arteriovenous malformation), identified most often in the mucosal lining of the upper stomach, that may cause severe spontaneous haemorrhage. It can rarely be found in the duodenum, colon, jejunum, or oesophagus. If detected endoscopically, curative therapy is often possible, although the abnormality is often difficult to see at gastroscopy. Surgical exploration may also be required if the bleeding is unresponsive to endoscopic treatment. G. Dieulafoy (1839–1911), French physician
Subjects: Medicine and Health.