Self-stabilizing colonic capsule endoscopy: pilot study of acute canine models

Design and implementation of a novel wireless modular capsule robotic system in pipe

Capsule endoscopy is a new type of technology in the diagnosis and treatment of digestive diseases, with painless and low invasive features. However, current capsule robots have many problems, such as over-sized, single function and lack of active locomotion control. This study proposed and designed a new wireless modular capsule robotic system in pipe. The modular capsule robots could move forward and backward in the pipe in the axial direction, turn in a bending environment, and achieve the rendezvous and separation action through the three-dimensional rotating magnetic field generated by the three-axis Helmholtz coils. In this paper, the drive system of the three-axis Helmholtz coils, the power supply control system, and the modular capsule robot structure were analyzed and designed respectively. Finally, a series of characterization experiments were carried out to evaluate the motion characteristics of the modular capsule robots, including the influence of the flow environment imitated to human body's gastrointestinal motility, the frequency of the input signal, and the different structure of the robots on the movement characteristics of the modular capsule robot in this study. The study also evaluated the turning characteristics of robots. Experimental results showed that under different circumstances, modular capsule robots had good motion characteristics, and the effectiveness of the modular functionality had also been verified.

Multiple gastric erosions diagnosed by means of capsule endoscopy in a dog

CASE DESCRIPTION A 6-year-old spayed female Golden Retriever was evaluated for a 2-week history of progressive hyporexia, signs of abdominal pain, and weight loss. CLINICAL FINDINGS Physical examination findings included mild signs of pain on palpation of the cranial part of the abdomen and a body condition score of 4 (scale, 1 to 9). A CBC revealed mild microcytosis and hypochromasia; results of serum biochemical analysis were within the respective reference ranges, and abdominal ultrasonography revealed no abnormalities. Capsule endoscopy was performed, and numerous gastric erosions and hemorrhages were detected, with rare dilated lacteals in the proximal aspect of the small intestine. TREATMENT AND OUTCOME Treatment was initiated with omeprazole and sucralfate for 6 weeks, and the dog was transitioned to a novel protein diet. Capsule endoscopy was repeated at the end of the initial treatment course and revealed overall improvement, with a few small erosions remaining; medical treatment was continued for an additional 2 weeks. At last follow-up 9 months after treatment ended, the dog was clinically normal. CLINICAL RELEVANCE Capsule endoscopy was useful for initial detection and subsequent reevaluation of gastrointestinal lesions in this patient without a need for sedation or anesthesia. Information obtained in the follow-up evaluation was valuable in identifying a need to extend the duration of medical treatment.

OdoCapsule: next-generation wireless capsule endoscopy with accurate lesion localization and video stabilization capabilities

In this paper, we propose a platform to achieve accurate localization of small-bowel lesions and endoscopic video stabilization in wireless capsule endoscopy. Current research modules rely on the use of external magnetic fields and triangulation methods to calculate the position vector of the capsule, leading to considerable error margins. Our platform, entitled OdoCapsule (a synthesis of the words Odometer and Capsule), provides real-time distance information from the point of duodenal entry to the point of exit from the small bowel. To achieve this, OdoCapsule is equipped with three miniature legs. Each leg carries a soft rubber wheel, which is made with human-compliant material. These legs are extendable and retractable thanks to a micromotor and three custom-made torsion springs. The wheels are specifically designed to function as microodometers: each rotation they perform is registered. Hence, the covered distance is measured accurately in real time. Furthermore, with its legs fully extended, OdoCapsule can stabilize itself inside the small-bowel lumen thus offering smoother video capture and better image processing. Recent ex vivo testing of this concept, using porcine small bowel and a commercially available (custom-modified) capsule endoscope, has proved its viability.

Wireless endoscopy in 2020: Will it still be a capsule?

Currently, the major problem of all existing commercial capsule devices is the lack of control of movement. In the future, with an interface application, the clinician will be able to stop and direct the device into points of interest for detailed inspection/diagnosis, and therapy delivery. This editorial presents current commercially-available new designs, European projects and delivery capsule and gives an overview of the progress required and progress that will be achieved -according to the opinion of the authors- in the next 5 year leading to 2020.

Suture marker lesion detection in the colon by self-stabilizing and unmodified capsule endoscopes: pilot study in acute canine models

BACKGROUND

Capsule endoscopy is a noninvasive method for examining the small intestine. Recently, this method has been used to visualize the colon. However, the capsule often tumbles in the wider colon lumen, resulting in potentially missed pathology. In addition, the capsule does not have the ability to distend collapsed segments of the organ. Self-stabilizing capsule endoscopy is a new method of visualizing the colon without tumbling and with the ability to passively distend colon walls.

OBJECTIVE

To quantitatively compare the detection rate of intraluminal suture marker lesions for colonoscopy by using a custom-modified, self-stabilizing capsule endoscope (SCE); an unmodified capsule endoscope (CE) of the same brand; and a standard colonoscope.

DESIGN

Four mongrel dogs underwent laparotomy and the implantation of 5 to 8 suture markers to approximate colon lesions. Each dog had both capsule endoscopy and self-stabilizing capsule endoscopy, administered consecutively in random order. In each case, the capsule was inserted endoscopically into the proximal lumen of the colon followed by pharmacologically induced colon peristalsis to propel it distally through the colon. Blinded standard colonoscopy was performed by an experienced gastroenterologist after the capsule endoscopies.

SETTING

Experimental study in a live canine model.

SUBJECTS

Four dogs.

INTERVENTION

Laparotomy, capsule endoscopy, colonoscopy.

MAIN OUTCOME MEASUREMENTS

Comparison of the marker detection rate of the SCE to that of the unmodified MiroCam CE and a colonoscope.

RESULTS

The average percentages of the marker detection rate for unmodified capsule endoscopy, self-stabilizing capsule endoscopy, and colonoscopy, respectively, were 31.1%, 86%, and 100% (P < .01), with both self-stabilizing capsule endoscopy and colonoscopy performing significantly better than the unmodified capsule endoscopy.

LIMITATIONS

Acute canine model, suture markings poorly representative of epithelial polyps, limited number of animals.

CONCLUSION

The proposed self-stabilizing capsule endoscope delivered a significant improvement in detection rates of colon suture markings when compared with the unmodified capsule endoscope.

Magnetic control system targeted for capsule endoscopic operations in the stomach--design, fabrication, and in vitro and ex vivo evaluations

This paper presents a novel solution of a hand-held external controller to a miniaturized capsule endoscope in the gastrointestinal (GI) tract. Traditional capsule endoscopes move passively by peristaltic wave generated in the GI tract and the gravity, which makes it impossible for endoscopists to manipulate the capsule endoscope to the diagnostic disease areas. In this study, the main objective is to present an endoscopic capsule and a magnetic field navigator (MFN) that allows endoscopists to remotely control the locomotion and viewing angle of an endoscopic capsule. The attractive merits of this study are that the maneuvering of the endoscopic capsule can be achieved by the external MFN with effectiveness, low cost, and operation safety, both from a theoretical and an experimental point of view. In order to study the magnetic interactions between the endoscopic capsule and the external MFN, a magnetic-analysis model is established for computer-based finite-element simulations. In addition, experiments are conducted to show the control effectiveness of the MFN to the endoscopic capsule. Finally, several prototype endoscopic capsules and a prototype MFN are fabricated, and their actual capabilities are experimentally assessed via in vitro and ex vivo tests using a stomach model and a resected porcine stomach, respectively. Both in vitro and ex vivo test results demonstrate great potential and practicability of achieving high-precision rotation and controllable movement of the capsule using the developed MFN.