Knowledge of the position and shape of the endoscope could overcome many challenges of performing colonoscopy, e.g., loop formation. A novel computer-assisted colonoscope (NeoGuide Endoscopy System) delivers a real-time, three-dimensional map of the tip position and insertion tube shape in addition to the video image of the colon lumen. The aim of this study is to evaluate the mapping capabilities of the NeoGuide Endoscopy System in terms of colonic looping, insertion depth, tip position, and tip angle formation.

Ten endoscopists with various levels of experience were each shown 70 map images generated by the NeoGuide endoscopy system in a benchtop anatomical colon model. First endoscopists were asked to determine the tip angle based on the map image and the system's corresponding tip positioning aid (20 images). In the second part they had to identify the scope-tip position in the colon model (40 images). In the third part ten images were presented for identification of colonic loops.

The tip angle was correctly identified in 99% (198/200) of images. Using only the map images the scope position was accurately determined in 87.5% (350/400). Identification of colonic looping of the scope was appropriate in 99% (99/100). Overall accuracy was 92.4%, and overall positive predictive value was 94.9%.

Three-dimensional map images generated by the NeoGuide endoscopy system provide accurate information regarding tip position, insertion tube position, and colonic looping.

The 20-year technology slump in endoscopic innovation is finally giving way to a flurry of technologies, of which many are directed specifically at improving or even replacing traditional colonoscopy. These technologies include "smart" overtubes, electronically mapped and driven instruments, and completely self-propelled devices. In addition to nonendoscopic technologies such as CT, these innovations may dramatically alter the practice of colorectal cancer screening, the "bread and butter" of gastroenterologists in this country. There are multiple and complex forces driving these changes, including a mismatch between the supply and demand in colonoscopy, patient convenience and comfort, costs, and more recently, a growing concern about the miss rate of conventional colonoscopy.

Gastrointestinal endoscopy is an evolving field kindled by technologic advances, scientific discoveries, and the innovative minds of endoscopists. The development and subsequent applications of overtubes in gastrointestinal endoscopy mirror this larger evolution. In this article, we review the development, applications, and complications associated with overtubes in gastrointestinal endoscopy.

In the recent past, the introduction of miniaturised image sensors with low power consumption, based on complementary metal oxide semiconductor (CMOS) technology, has allowed the realisation of an ingestible wireless capsule for the visualisation of the small intestine mucosa. The device has received approval from Food and Drug Administration and has gained momentum since it has been more successful than traditional techniques in the diagnosis of small intestine disorders. In 2004 an esophagus specific capsule was launched, while a solution for colon is still under development. However, present solutions suffer from several limitations: they move passively by exploiting peristalsis, are not able to stop intentionally for a prolonged diagnosis, they receive power from an internal battery with short length, and their usage is restricted to one organ, either small bowel or esophagus. However the steady progresses in many branches of engineering, including microelectromechanical systems (MEMS), are envisaged to affect the performances of capsular endoscopy. The near future foreshadows capsules able to pass actively through the whole gastrointestinal tract, to retrieve views from all organs and to perform drug delivery and tissue sampling. In the long term, the advent of robotics could lead to autonomous medical platforms, equipped with the most advanced solutions in terms of MEMS for therapy and diagnosis of the digestive tract. In this review, we discuss the state of the art of wireless capsule endoscopy (WCE): after a description on the current status, we present the most promising solutions.

In upper endoscopy, overtubes protect the hypopharynx and esophagus in patients requiring multiple esophageal intubations. Transesophageal echocardiography (TEE) is frequently used in general cardiology practice to provide high-resolution, real-time images of cardiac structures that are often not visualized by transthoracic imaging alone. Patients with a history of esophageal disorders or difficult esophageal intubations may have increased risk for complications from the echoprobe. An esophageal overtube may facilitate TEE in such patients.

We sought to evaluate the usefulness of upper endoscopy with placement of an esophageal overtube to facilitate TEE in patients with prior difficult esophageal intubations.

We performed upper endoscopy, followed by placement of an esophageal overtube, in 4 patients who had an unsuccessful intubation with the TEE probe. The endoscopic procedures were successfully completed, thus, allowing for uneventful subsequent TEE.

Upper endoscopy with placement of an esophageal overtube may allow for safe successful completion of TEE in patients with previously unsuccessful blind esophageal intubation.

In the past few years, several groups of investigators have developed colonoscopic instruments or accessories to speed up the examination and make it more tolerable for patients. The NeoGuide Endoscopy System has the computer processing ability to direct each 8-cm segment of its colonoscope to bend at the exact place where the leading segment turned around a corner. This follow-the-leader system is intended to reduce loops and ensure comfort through preventing excess pressure on the colon wall by making a turn without the usual maneuver of pushing on the wall to advance the scope.

Unsedated colonoscopy is an uncomfortable procedure for most patients. Discomfort during colonoscopy is largely related to looping of the colonoscope, which displaces the colon from its native configuration and stretches attachments to the mesentery. A novel computer-assisted colonoscope utilizes a fully articulated, computer-controlled insertion tube. On manual insertion of the colonoscope, the position and angle of the scope's tip are encoded into a computer algorithm. As the colonoscope is advanced, the computer directs each successive segment to take the same shape that the tip had at a given insertion depth. The insertion tube thus changes its shape at different insertion depths in a "follow-the-leader" manner.

This initial clinical trial with this novel colonoscopy system was designed as a prospective, nonrandomized, unblinded, feasibility study. Three physicians of varying levels of experience participated in the study.

Eleven consecutive patients (seven men, four women, age range 19-80) meeting inclusion criteria for screening or diagnostic colonoscopy were enrolled in the study. The cecum was reached in 10 consecutive patients (100%). Findings included diverticular disease in two cases and multiple colonic polyps in two cases. Postprocedure assessment at discharge, 48 h, and 30 days revealed no complications or adverse effects. Physician satisfaction and patient acceptance of this new technique were high.

In this limited, first of its kind feasibility study, the computer-assisted colonoscope was shown to perform colonoscopy safely and effectively. The colonoscope's unique design limited loop formation during colonoscopy. Large-scale clinical trials are indicated.