Balloon enteroscopy for small bowel bleeding

Lars Aabakken, Chief of GI Endoscopy
Rikshospitalet University Hospital
Oslo, Norway

The double balloon enteroscope (DBE) was invented in Japan, by Yamamoto and co-workers. However, a substantial amount of the initial experience, exploration and documentation of this exquisite tool has been carried out in Europe. The first publication appeared as early as 2003, when the group of Dr. Ell, in collaboration with dr. Yamamoto assessed the feasibility of the tool in 8 subjects with obscure gastrointestinal bleeding and abdominal pain. In this particular study, the anal route was used in half of the subjects, and the entire small bowel navigated in two, both rather rare events in most clinical settings today. However, the findings were clear-cut, verifying capsule findings, and therapeutic output was substantial, paving the way for numerous other and larger studies to define the present role of small bowel enteroscopy.

Shortly after the DBE enteroscope, the single balloon instrument was introduced by Olympus. The intubation technique is quite similar, but tip fixation is accomplished by deflection, rather than using a tip balloon. This seems to have little impact on the performance of the instrument, but handling is easier, with only one balloon to handle and no pre-procedure balloon mounting. Comparisons between the two models are on-going. More recently, the spiral sheath enteroscope was also introduced. This instrument has a spiral contour outer sheath that is rotated to facilitate small bowel intubation. The method appears to be quicker than the balloon instruments, although the depth of intubation may be less.

Device-assisted enteroscopes (DAE), in particular the therapeutic instruments with the 2.8 or 3.2 mm channel, offer a range of endoscopic interventions. May and coworkers recently published a large series of 653 consecutive procedures in 353 patients from a large European material. In this series, a diagnostic yield of 75 % and a therapeutic yield of 67 % overall. Endoscopic therapy was performed in 59 % of the therapeutic cases (139/236), with a total of 176 therapeutic procedures. APC treatment was by far the most common intervention (102 sessions), but dilations, polypectomy, injection and foreign body extractions were also successfully performed. Severe treatment-associated complications occurred in six of the 178 therapeutic procedures (3.4 %) and 4/139 patients (2.9 %), but no mortality was reported.

This and other studies prove that small bowel bleeding remains the most significant indication for diagnostic and therapeutic DAE. The typical scenario is patient with obscure GI bleeding and usually a positive capsule endoscopy study. Depending on the suspected type and location of the bleeding source, the oral or anal route of introduction is selected. For hemostatic purposes, APC is the most widely used, telangiectasias being the most frequent lesion. However, injection therapy, clipping, and polypectomy in cases of bleeding polyps, are also available modalities through the DAE instrument. Data from recent studies will be presented, but the diagnostic, as well as the therapeutic yield of DAE has long since established this as the tool of choice for small bowel bleeding amenable to endoscopic therapy. Even in surgical cases, localization and characterization of lesions is vital, with tattooing of lesions allowing simplified surgical resections, even with laparoscopic techniques.