The Evolution of Device-Assisted Enteroscopy: From Sonde Enteroscopy to Motorized Spiral Enteroscopy

The introduction of capsule endoscopy in 2001 opened the last “black box” of the gastrointestinal tract enabling complete visualization of the small bowel. Since then, numerous new developments in the field of deep enteroscopy have emerged expanding the diagnostic and therapeutic armamentarium against small bowel diseases. The ability to achieve total enteroscopy and visualize the entire small bowel remains the holy grail in enteroscopy. Our journey in the small bowel started historically with sonde type enteroscopy and ropeway enteroscopy. Currently, double-balloon enteroscopy, single-balloon enteroscopy, and spiral enteroscopy are available in clinical practice. Recently, a novel motorized enteroscope has been described with the potential to shorten procedure time and allow for total enteroscopy in one session. In this review, we will present an overview of the currently available techniques, indications, diagnostic yield, and complications of device-assisted enteroscopy.

Motorized Spiral Enteroscopy: to infinity and beyond?

With the advent of device-assisted enteroscopy (DAE) in the early 2000s, endoscopic access to the entire small bowel is possible nowadays (1). And yet, there is still room for improvement. Total enteroscopy remains a time-consuming procedure, often combining the antegrade (oral) and retrograde (anal) approach with only a reasonable chance to obtain complete endoscopy of the entire small bowel (2). Therefore, the aim is to go faster, deeper and to perform more advanced therapeutic interventions within the long and tortuous small bowel. Moreover, DAE was also shown to be effective to perform endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy and to complete colonoscopy in patients with previously incomplete conventional colonoscopy due to long dolichocolon (3). The latest DAE development is Motorized Spiral Enteroscopy (MSE), initially conceptualized as a manually driven rotational spiral overtube by Paul A. Akerman, and further developed and commercialized as a motorized spiral overtube by the Olympus Medical Systems Corporation (4). Initial feasibility trials have shown that MSE can compete with already available DAE techniques (single- and double-balloon enteroscopy) with regard to diagnostic yield and endotherapy within the small bowel (5,6). However, being a short type enteroscope of 168 cm (as compared to the 200 cm long single- and double-balloon enteroscopes), MSE appears to be even more effective in obtaining deep and total enteroscopy with a relatively short procedural duration (2,6). In addition, the working channel diameter is increased to 3.2 mm (as compared to 2.8 mm) with an extra irrigation channel, facilitating therapeutic interventions within the small bowel. This faster and deeper (but more aggressive) enteroscopy technique comes with the price of an increased risk of mucosal injuries (ranging from superficial bruising to laceration and even perforation) within the oesophagus and the small bowel, luckily remaining asymptomatic most of the time without any clinical consequence (6). So far, this promising new technique has the potential of becoming a gamechanger in the still evolving field of deep enteroscopy.

Role of Small Bowel Endoscopy in Diagnosis and Management of Inflammatory Bowel Disease: Current Perspective

The evaluation of small bowel in inflammatory bowel disease (IBD) is mainly performed in cases with newly diagnosed or suspected Crohn’s disease (CD). The available modalities for small bowel evaluation include radiological imaging (barium meal follow through, magnetic resonance enteroclysis, computed tomography enteroclysis) and small bowel endoscopy also known as enteroscopy. The main advantage of small bowel endoscopy over radiological imaging is that it allows for obtaining biopsy specimen required for histological confirmation of the diagnosis. Various endoscopic modalities for endoscopic evaluation of small bowel include push enteroscopy and device assisted enteroscopy (DAE). Push enteroscopy allows only limited evaluation of proximal small bowel. Therefore, DAE is generally preferred over push enteroscopy for small bowel evaluation. DAE includes single balloon enteroscopy, double balloon enteroscopy, and spiral enteroscopy. The available literature suggests that there is no significant difference in the diagnostic yield among the available DAE devices. Therefore, the choice of DAE is largely dependent on the availability as well as local expertise. More recently, motorised spiral enteroscopy has been introduced. The main advantage of this novel DAE is ease of use with the possibility of evaluating the entire small bowel via per-oral route. However, the data regarding the use of motorised spiral enteroscopy is limited and comparative trials are required in future.