Capsule Endoscopy: Treatment, Effects & Risks

Capsule endoscopy is a diagnostic procedure that has been in use since 2001. The patient swallows a capsule camera, which automatically sends images of the mucosal surface to a data recorder as it travels through the digestive tract. The image sequences can then be reviewed by a medical specialist.

What is capsule endoscopy?

In a capsule endoscopy, the patient swallows a capsule camera that sends images of the mucosal surface as it travels through the digestive tract. The image sequences can then be reviewed by a specialist. The swallowable capsule is a disposable medical device that is excreted naturally. The capsule is therefore not reused, contrary to frequent opinions to the contrary. Images are taken of all sections of the gastrointestinal tract with the exception of the oral cavity. The images of the gastric mucosa and the small and large intestines have proven to be particularly valuable for diagnosis. The small intestine in particular is not accessible or only accessible to a limited extent using conventional colonoscopic methods. With the help of capsule endoscopy, it is now possible to view the mucosa of the small intestine in its entirety and thus to evaluate it diagnostically. Therefore, capsule endoscopy serves as the so-called gold standard of primary diagnosis of diseases of the small intestine. A conventional colonoscopy cannot be performed in some patients for a variety of reasons. Some patients also refuse this examination method. In these cases and also when conventional colonoscopy carries too high risks, capsule endoscopy is used as an alternative. Just one year after capsule endoscopy was first described, it was launched on the market as early as 2001. Camera capsule systems are now offered and distributed by various manufacturers.

Function, effect and goals

Since the first use of capsule endoscopy in 2001, the procedure has been further developed and optimized. For example, it is now possible to use separate camera types for each section of the digestive tract that are adapted to it. Capsule endoscopic examinations have become established in Europe primarily for imaging the mucosa of the large and small intestines, but not for the final assessment of the stomach and esophagus. The camera is tiny, similar in size to a film-coated tablet and easily swallowed. It is an absolutely waterproof and free-floating microdigital camera. The dimensions are about 2.6 centimeters in length and 1.1 centimeters in width, depending on the model. Sophisticated transmission and control electronics allow the recording frequency to adapt to the speed at which the camera travels through the different sections of the digestive tract. In fast passages, up to 6 images per second are shot. The images are recorded by a data recorder carried by the patient during the examination. The high-quality lithium ion battery guarantees recording times of up to 12 hours. The battery also powers the camera’s illumination during the gastrointestinal passage. A colon camera capsule usually contains 2 cameras, one at each end. This provides almost an all-around view. As with conventional colonoscopy, the patient must thoroughly cleanse the entire gastrointestinal tract before the examination. Without this elaborate cleaning procedure, food and fecal residues remain, making an unclouded view of the mucosa impossible. During the 5-12 hour journey through the human digestive tract, the capsule camera takes up to 60000 images. During the examination, the patient is at most slightly affected by the data recorder, but not by the capsule camera itself, which cannot be felt or otherwise perceived at all. In small bowel capsule endoscopy as a gold standard, the method is mainly used for diagnosis and follow-up of inflammatory mucosal changes caused by celiac disease or Crohn’s disease. Capsule endoscopy is approved in Germany for children as young as 2 years of age. It can also be used in veterinary medicine; only larger veterinary practices or veterinary clinics offer the procedure. Main indications for colon capsule endoscopy are bleeding or tumor search. In Germany, capsule endoscopies of the small and large intestine have been included in the benefits catalog of the statutory health insurance funds for certain indications.

Risks, side effects and dangers

Capsule endoscopy is for diagnostic purposes only; no therapeutic views can be performed, for example, to ablate polyps or remove tissue samples, as is the case with conventional colonoscopy. Since the capsule camera is a sterilely packaged disposable item, there is no hygiene risk and no risk of infection. The willingness to participate in cancer screening examinations could be significantly increased with capsule endoscopy, because the procedure is considered to be particularly patient-friendly. The most important contraindication to the use of the capsule camera is stenosis, which could obstruct passage of the capsule. In order to test the patency of the intestinal passage in advance, a so-called patency capsule can be swallowed in cases of doubt. This is identical in size and shape to the capsule camera and would dissolve into tiny individual fragments by itself after about 30 hours if it cannot be excreted. Pregnancy, dysphagia are also contraindications. If a patient has swallowed the capsule camera, then MRI examinations are ruled out until it is excreted with the stool, as the capsule camera contains magnetic components. An MRI examination could therefore be life-threatening. However, capsule endoscopy has not yet become widespread, which is probably also due to the very high costs per application. The risks of using capsule endoscopy are considered to be low to very low. No case of a significant side effect has been documented in the German-language medical literature since its introduction in 2001.