Capsule Endoscopy - Wireless Capsule Endoscopy

Several meters of small bowel lie beyond the reach of a gastroscope and a colonoscope. A camera the size of a vitamin pill films all of it.

In wireless capsule endoscopy you swallow a 26 millimeter capsule that holds a camera, a light and a transmitter, and it films the lining of the small bowel for eight hours or more while you go about your day. No tube is passed and no sedation is given. A review of 227 studies covering 22,840 examinations found an abnormality in 59 percent of them, and in bleeding of unknown origin the capsule found a significant cause twice as often as the older tube test, 56 percent against 26 percent.

What capsule endoscopy is

Capsule endoscopy examines the small bowel, the long middle section of the gut where food is absorbed. A gastroscope reaches its first part. A colonoscope reaches its last few centimeters. Everything between the two, several meters of it, stayed out of sight until the capsule arrived. The device measures 11 by 26 millimeters. It takes between two and six pictures a second and sends them to a recorder worn on a belt. The normal movement of the bowel carries it along, it leaves the body in the stool a day or two later, and it is flushed away, since each capsule is used once.

This table scrolls sideways on a narrow screen. Swipe or drag to see every column.

No other test shows the whole lining without anesthesia.

When it is the right test

Three situations account for nearly every examination.

Bleeding with no source found

Blood loss from the gut that a gastroscopy and a colonoscopy have both failed to explain is the leading reason for a capsule examination, and it accounted for 66 percent of the 22,840 procedures in the review by Liao and colleagues. The 2022 guideline of the European Society of Gastrointestinal Endoscopy, written by Pennazio and colleagues, recommends the capsule as the first test in this situation, ahead of any other endoscopic or radiological examination. The comparison behind that advice comes from a meta-analysis by Triester and colleagues. Across 14 studies that put the capsule against push enteroscopy, the older method of pushing a long endoscope down from the mouth, the capsule found a clinically significant lesion in 56 percent of patients and the endoscope in 26 percent. Fragile, widened blood vessels called angiodysplasia made up half of what was found in bleeding patients in the Liao review, and these flat red spots are exactly the kind of lesion that a CT scan cannot show.

56% vs 26%

Clinically significant findings with the capsule and with push enteroscopy in unexplained bleeding. One extra diagnosis for every three patients tested. Am J Gastroenterol, 2005.

Timing decides the yield

A bleeding point is easiest to see while it bleeds, so European guidance asks for the capsule as soon as possible after visible bleeding, ideally within 48 hours. Someone who passed black stools last week should therefore have the test where they are. This week. Waiting for a flight throws away the best chance of a diagnosis.

Iron-deficiency anemia

Slow, invisible blood loss shows up as falling iron stores and a low blood count. When the stomach and the colon have been cleared, the small bowel is the next place to look, and the European guideline names the capsule as the first-line examination for it. The Canadian guideline by Enns and colleagues is more selective and reserves the capsule for patients whose anemia is unexplained and persistent.

59 in 100

Capsule examinations that detected an abnormality, pooled from 227 studies. Gastrointest Endosc, 2010.

What has to come first

Three things have to be done first. They are a gastroscopy with biopsies from the duodenum to exclude celiac disease, a colonoscopy of good quality, and a review of diet, periods in women, and tablets such as aspirin and other anti-inflammatory painkillers, which themselves cause small-bowel ulcers. The capsule comes after those, never in place of them.

Suspected or known Crohn's disease

Crohn's disease starts, in many patients, in stretches of small bowel that a colonoscope cannot reach. For a patient with typical symptoms, raised inflammation markers and a normal colonoscopy with a look into the last part of the small bowel, the European guideline recommends the capsule as the first way to examine the rest, provided there are no symptoms of blockage and no known narrowing. That condition matters, as the next figure shows.

8.2% vs 2.7%

Capsules that got stuck in patients with established inflammatory bowel disease, without and with a check for narrowings beforehand. Gastrointest Endosc, 2017.

The patency capsule

A patency capsule is a dummy of the same size made of material that dissolves. You swallow it a day or two before the real one. If it leaves the body intact, or a scan shows it has reached the colon within 30 hours, the way is clear. If it lodges, it softens and breaks up by itself. Every patient with established Crohn's disease should have one first, according to the European guideline.

Less common reasons

Surveillance of inherited polyposis syndromes, celiac disease that keeps causing symptoms despite a strict diet, and a suspected small-bowel tumor on a scan are the remaining accepted reasons in the Canadian guideline.

When it is the wrong test

Some clinics market the capsule as a comfortable substitute for ordinary endoscopy. It is no such thing.

The Canadian guideline advises against it for long-standing abdominal pain or diarrhea when blood tests and stool markers of inflammation are normal, since the chance of a useful finding is low and the chance of a confusing minor one is high. It should not be used to make the diagnosis of celiac disease, which needs biopsies. A colon capsule exists. The same guideline states that it should not routinely replace colonoscopy, because any polyp it shows still has to be removed with a colonoscope. People with symptoms of a blocked bowel, a known narrowing, or a swallowing disorder need a different plan. Pregnancy is a reason to postpone. A pacemaker or an implanted defibrillator has to be declared so that the maker's guidance for the capsule system can be checked. And a person who simply dislikes the idea of a colonoscopy, with no bleeding, no anemia and no sign of inflammation, gains nothing from a capsule, because a normal result would not remove the need for the colonoscopy and an abnormal one would only bring it forward.

Three things every patient should hear first

The examination can fail, the capsule can get stuck, and a lesion can be missed. Clinical practice guideline, Gastroenterology, 2017.

The examination, hour by hour

The days before

Iron tablets stop five days ahead. They coat the bowel black. Declare blood thinners, diabetes medication and any tablet that slows the gut, such as strong painkillers, and expect breakfast and a light lunch on the day before to be followed by clear fluids only.

Risks, led by capsule retention

How often a capsule gets stuck

Retention means the capsule is still inside two weeks after it was swallowed, held up at a narrowing that nobody knew about. Liao and colleagues put the overall rate at 1.4 percent. Rezapour and colleagues broke it down by reason for the test in a 2017 meta-analysis and found 2.1 percent in unexplained bleeding, 3.6 percent in suspected inflammatory bowel disease and 8.2 percent in established disease. Narrowings cause it. Crohn's disease, anti-inflammatory painkillers, previous radiotherapy to the abdomen or pelvis, and tumors produce them. Where a patency capsule or a CT enterography was done first, the rate in bowel disease fell to 2.7 percent.

Each of those figures argues for checking the bowel first in anyone at risk.

What retention feels like

How a retained capsule is removed

Other ways the test can fall short

One examination in six is incomplete. The pooled completion rate in the Liao review was 83.5 percent, meaning the battery ran out before the capsule reached the colon in the rest, most often because the stomach emptied slowly. Lesions can be missed, since the capsule tumbles and sees each fold once. A few people cannot swallow it. A doctor then places it in the duodenum with a gastroscope under sedation.

Results, and what follows them

How the video is read

The recorder holds tens of thousands of still pictures. Software strings them into a film, flags frames that contain red, and a gastroenterologist then watches the whole length, which takes between 30 and 90 minutes of concentrated viewing. Private hospitals in this market and in the United Kingdom quote one to three working days for the written report.

What the report contains

Transit times through the stomach and the small bowel, a statement on whether the colon was reached, the quality of the view, each finding with its still frames and its estimated position, and a recommendation. Ask for the video file as well as the report. A second reader at home can then review it without repeating the test.

When the capsule finds something

Device-assisted enteroscopy comes next. The European guideline names it to confirm and, where possible, treat what the capsule showed. The doctor seals bleeding vessels with heat, removes polyps and samples narrowings. That means a separate procedure under anesthesia, with its own consent and its own quote, and it can be arranged in Istanbul or at home with the capsule report in hand. If the pictures point to Crohn's disease, treatment is medical and belongs with a gastroenterologist who will follow you for years, which for most travelers means the one at home.

When it finds nothing

A clean, complete examination is a result too.

After a high-quality negative capsule study in a patient with suspected small-bowel bleeding, the European guideline recommends watching and treating the anemia without further invasive tests. Doctors consider a repeat only if bleeding returns.

Planning it from abroad

How long to stay in Istanbul

Three working days cover it.

Day one holds the consultation, the review of earlier reports and the start of the bowel preparation. Day two belongs to the examination. On day three, or day four at the latest, the gastroenterologist goes through the findings with you in person, with an interpreter if you need one. Add two days when a patency capsule is required first.

Flying with the capsule still inside

Cabin pressure does not affect the capsule, and no airline rule forbids it. Two cautions apply. An MRI scan is forbidden until the capsule has passed, so carry the card that says you have had the test, and anyone with cramping or vomiting should be seen by a doctor before boarding.

What the cost depends on

The capsule itself is the main item, since it is a single-use device, and systems from different makers are priced differently. A patency capsule beforehand adds a second device and a scan. The reading fee reflects an hour or more of a specialist's time. Blood tests, a gastroscopy or a colonoscopy that turn out to be missing or out of date, and any placement of the capsule by endoscope are counted separately. Published packages from hospitals in Istanbul and medical travel agencies cover the consultation, the capsule, the reading and the report, an interpreter and transfers, and they leave out the hotel, flights, a patency test, enteroscopy for any finding and the treatment of a retained capsule. Your own history moves the figure as well. Previous bowel surgery, Crohn's disease, diabetes that slows the stomach and blood thinning tablets each change which steps are needed, and a patient who arrives with complete, recent endoscopy reports pays for fewer of them than one who arrives with none.

Send the reports first. A quote written without them is a guess, and the review of them is free.

The trip

One coordinator in the international patients office handles the case from the first message to the day you leave. The team works in English, Arabic, French, Russian, Serbian, Romanian and Spanish, arranges interpreters for other languages, books the hotel and the transfers, and sends the appointment confirmation with an invitation letter naming the hospital and the treating doctor ten days before you travel. As an outpatient test, capsule endoscopy involves no hospital room unless something else is planned. Two family members may join the consultation. Mention halal, vegetarian or diabetic needs, because the preparation day involves a set diet, and mention a wish for a female doctor in the first message so that the department can arrange it when the rota allows. The hospital has a prayer room. Bring a companion if you possibly can, since the preparation day and the long day wearing the recorder pass more easily with company.

After you fly home

Once you are back home the file you carry should hold the written report in English, the video on a memory stick, and a letter for your own gastroenterologist that states what was found and what is advised. The coordinator stays reachable on the same WhatsApp number. Questions on the report are passed to the doctor who read the film.

• Watch for the capsule in the stool for the first few days, and tell the coordinator if you saw it
• If you have not seen it after two weeks, ask your own doctor for a plain X-ray of the abdomen
• Do not have an MRI scan until passage is confirmed
• See a doctor the same day for cramping pain with vomiting, a swollen abdomen, fever, or difficulty swallowing and chest pain that began with the capsule

Anemia treatment continues whatever the capsule showed. Your own doctor arranges the iron and a blood count after six to eight weeks.

Capsule Endoscopy - Wireless Capsule Endoscopy FAQ