Dr McLaughlin trained in balloon assisted and device assisted enteroscopy at St. Thomas’ Hospital London under the supervision of Dr SHC Anderson during a year long clinical attachment and further experience at St, Thomas’ hospital.
Background to the test
Enteroscopy involves examination of the small bowel using a special camera. The small bowel lies between the stomach and the large bowel (colon). The upper small bowel (duodenum) is accessed during standard gastroscopy and the last part of the small bowel (terminal ileum) can also be reached during colonoscopy but until recently it has not been possible to examine endoscopically (and hence take biopsies or provide endoscopic treatment) to the entire 4-6 metres of small bowel.
Video capsule endoscopy (click here for description) allows high quality images of the entire small bowel to be obtained but does not allow biopsies to be taken or endoscopic treatment to be administered. Indications for enteroscopy include small bowel abnormalities identified at video capsule endoscopy or abnormalities found at X-ray tests of the small bowel (MRI, CT or small bowel follow-through). Common abnormalities requiring enteroscopy include obtaining histological biopsy in suspected Crohn’s disease, treatment of angioectasia (abnormal blood vessels) which can cause anaemia or small bowel bleeding and dilatation of strictures (narrowings) within the small bowel.
Essentially three techniques allow endoscopic examination (and treatment) of the small bowel. These are push enteroscopy, balloon assisted enteroscopy and device assisted enteroscopy.
Push enteroscopy
Push enteroscopy is the oldest and simplest small bowel endoscopic technique. Push enteroscopy is similar to gastroscopy but uses a longer endoscope which allows deeper insertion into the small bowel. The test can be performed following a sedative or under general anaesthesia. Push enteroscopy can be a useful technique when video capsule endoscopy (or other small bowel imaging techniques) have identified abnormalities in the upper small bowel but it is unable to reliably reach abnormalities which are beyond the first 1 metre of small bowel.
The test itself usually takes about half an hour and can be performed following a sedative or under general anaesthesia.
Balloon enteroscopy
In recent years advanced techniques have allowed ‘deep enteroscopy`, in fact these techniques can allow complete endoscopic examination (and administer endoscopic treatment) to any part of the small bowel and therefore avoid the need for surgery in the majority of cases.
Balloon enteroscopy is a specialized endoscopic technique which complements video capsule endoscopy. In the majority of cases video capsule endoscopy is performed first to identify and locate abnormalities within the small bowel. Any abnormalities found can then be reached using a balloon enteroscope. Abnormalities identified in the upper two-thirds of the small bowel are usually approached from the oral-end (mouth) and those in the lower third of the small bowel are usually approached via the anus. The test is performed using a special ‘balloon enteroscope` this enteroscope utilises one or two balloons mounted on the end of the enteroscope and the overtube to fix the highly mobile small bowel, avoid the formation of loops and allow deeper insertion of the enteroscope (endoscopy camera).
The test itself usually takes between an hour to an hour and a half and can be performed following a sedative or under general anaesthesia.
Device assisted enteroscopy
Device assisted enteroscopy is the most recent ‘deep enteroscopy` technique to be described.
It is performed using a spiral overtube which fits over the enteroscope and is also known as ‘spiral enteroscopy`. The spiral device is inserted into the small bowel with the enteroscope and allows pleating of the small bowel over the enteroscope which shortens the small bowel and prevents looping of the mobile small bowel during insertion.
Similar to balloon enteroscopy spiral enteroscopy is a specialized endoscopic technique which complements video capsule endoscopy. In the majority of cases video capsule endoscopy is performed first to identify and locate abnormalities within the small bowel. Device assisted enteroscopy is most commonly performed to access the upper two-thirds of the small bowel but can also be used to examine the lower small bowel. Although research suggests that balloon assisted enteroscopy allows deeper insertion via this route than device assisted enteroscopy.
The test itself usually takes between an hour to an hour and a half and can be performed following a sedative or under general anaesthesia.
Complications
These tests are usually very safe but in common with all endoscopic examinations carry the risk of perforation (a hole in the bowel), bleeding and also the risks of sedation or general anaesthesia. In addition balloon and device assisted enteroscopy are associated with a small risk of pancreatitis. These risks vary between patients depending on the indications for the procedure and will be discussed in detail before the test is performed.