Fig. 23.32 
Insulinoma: demonstrated by CT angiography. 
CT angiography is probably the most sensitive means of detecting small islet cell tumours pre-operatively. This CT scan was obtained immediately after the injection of contrast medium into the coeliac axis. It shows a small insulinoma in the tail of the pancreas, Iying at the splenic hilum, which was not detected on the initial angiogram. Transhepatic venous sampling may be helpful in locating an insulinoma not detected by CT and/or angiography.