Capsule Endoscopy - The Large Bowel (Intestine)

Taking a ‘tour’ through the winding large bowel: an innovative examination using capsule endoscopy. By Prof. Rami Eliakim, a gastroenterologist at Herzliya Medical Center Hospital.

Cancer of the large bowel is perceived today, and rightly so, as one of the most dangerous types of cancer. It is considered to be a particularly common type of cancer, and also one of the most deadly the types of cancer known to modern medicine.

• On the one hand, this is cancer that is very difficult to identify: it develops deep within the large bowel, in one of the most internal and convoluted organs of the body, making it very difficult t fully survey and diagnose it.
• On the other hand, early diagnosis makes it preventable – one of the few types of cancer that can be effectively prevented if this is done in time.

The early diagnosis of this type of cancer is therefore of supreme importance. How can cancer of the large bowel be diagnoses?

How can cancer of the large bowel be diagnoses?

Cancer of the large bowel develops, in many instances, from polyps that develop in this organ. While there are other known factors for the development of large bowel cancer (heredity, chronic bowel inflammation, certain foods, etc.), polyps are nevertheless considered to be the main risk factor: they grow as benign tumors in the initial stages, but at a certain stage they undergo a change and become malignant. At this critical stage, it will be much more difficult to treat them, to prevent the development of the disease and to stop its spread.

The Ministry of Health invests much effort in activities for the early detection of this disease, mainly by means of public information campaigns and increasing awareness of this subject. Patients who understand that diagnosis is a life-saving procedure attend examinations more often so that they will really be able to diagnose problematic polyps in time – when they are still in their early stages of development, before becoming malignant.

Examinations for diagnosis – the advantage offered by a small, smart capsule

In order to diagnose polyps in the bowel, it is necessary to undergo gastroenterological examinations, such as colonoscopy, virtual colonoscopy, sigmoidoscopy (endoscopy of the left large bowel) and others, alongside fecal occult blood testing.

The Ministry of Health recommends undergoing these tests once a year in the framework of what is called ‘screening tests’.

These examinations are performed with the aim of ruling out the development of polyps in the bowel, but they are known as unpleasant examinations, being invasive to some extent. Many patients undergo these examinations under deep sedation, some even under general anesthesia. This is also the reason why compliance with this is not at all high, and many people avoid undergoing these screening tests. Thus, without being conscious of this, they are significantly reducing the chance for early detection of the disease.

An innovative development – which in spite of having been on the market for several years already, its use in the general community is still in its infancy – could solve this problem. It utilizes an endoscopic capsule, which enables a complete and optimal survey of the large bowel, and requires only one action on the part of the patient: to swallow it with water, just like swallowing a capsule or pill containing medicine.

A tiny capsule, with a pair of cameras inside

This small capsule, developed by the Israeli company Given Imaging, is similar in size to other capsules that are on the market. It is smooth and oval, less than three cm in length and just over one centimeter in width. It weighs some three grams and can be easily swallowed.

These characteristics are no indication of the capsule’s capabilities:

• It contains two cameras, which together provide a field of view of almost 360 degrees, and photograph between 4 and 34 frames per second.
• It has a small but powerful illumination source, providing good illumination of the bowel and enabling the provision of clear, sharp pictures, essentially making it perfectly suited for the shape and characteristics of the convoluted bowel.
• The capsule also contains a special battery, which thanks to an additional important characteristic – movement-based photographing – can work continuously even for over ten hours.
• The capsule utilizes the bowel’s natural action, and slowly progresses through its entire length, and during its journey, it conveys the pictures directly to sensors and receivers that are on a special belt worn in advance around the patient’s hip.

The capsule offers a great many advantages: it does not require sedation, anesthesia or any level of radiation to complete its action; it involves no pain; it is taken simply and easily, and the patient can continue with his usual activities with almost no disturbance; it is evacuated from the body naturally, thus completing the particularly comfortable, simple and easy course of the examination.

What about the results of the examination?

One of the most fundamental questions that arose following the development of capsule endoscopy was about its level of efficiency: to what extent is it capable of providing good results, as compared to other gastroenterological examinations performed today?

Studies performed over the years reveal a clear picture: so far as the capsule’s sensitivity in detecting polyps in the large bowel is concerned (both small and large polyps), it does not fall short of the other examinations.

Various studies have even shown particularly good results during examination with the capsule – even to the extent of identifying twice as many findings (!) as detected by the ‘traditional’ examinations.

The conclusion, then, is clear: capsule endoscopy provides a superb solution for patients who need to undergo screening tests of the large bowel, and for those who have undergone various tests that raise the suspicion of the development of polyps in the bowel, and even for those who suffer from chronic bowel inflammation. This examination is simple, effective and comfortable to perform, both for the patient and for the medical team.