Overview of Capsule Endoscopy
A capsule endoscopy is a special type of test for your gut. It uses a mini camera inside a small, swallowable case – people often call it a “pill camera”. This device can take pictures of the inside of your stomach and intestines.
Capsule endoscopy was first performed in 1999 and was approved for use in the United States in 2001. The first one was called the M2A capsule. This stands for ‘mouth to anus’, which shows you that the capsule travels right through your digestive system. It was later renamed the PillCam SB, which stands for ‘small bowel’.
Once you swallow the capsule, it begins to take pictures at a speedy rate of 2 to 6 frames per second for about 8 to 12 hours, until its battery runs out. These pictures are really clear and detailed, which helps doctors see things they might not be able to see during a normal check-up.
Afterwards, a specialist doctor known as a gastroenterologist reviews the images. One drawback of this method is that sometimes, the battery of the capsule runs out before all necessary images have been taken. This happens in about 1 in 6 cases.
A capsule endoscopy is a diagnostic method, which means it can help identify potential health issues. However, it does not have any direct treatment benefits. It can find problems in the esophagus, stomach, small bowel, and colon; but it can’t be used to take a tissue sample or provide therapy.
The test is usually used for people who keep having unexplained bleeding in their gut after other tests failed to identify where the bleeding is coming from. It can also be helpful to pinpoint where a lesion (an area of damaged tissue) is before a patient undergoes other medical procedures. Research has found that capsule endoscopy is more successful at finding the cause of problems in the small bowel compared to other techniques like barium studies, CT scans or push endoscopy.
Anatomy and Physiology of Capsule Endoscopy
Capsule endoscopy is a medical test used to examine different parts of the digestion system including the esophagus (the tube connecting the mouth to the stomach), the stomach itself, the small intestine, and the large intestine (colon). The process is simple and involves swallowing a capsule like you would a normal pill.
Once the capsule is swallowed, it moves down the esophagus into the stomach, just like food. From there, it passes through a gate-like muscle called the pyloric sphincter into the small intestine, which consists of three parts- the duodenum, jejunum, and ileum.
The capsule continues its journey into the large intestine (colon) through a valve that connects the small intestine and colon (the ileocecal valve). It will then move through the colon and finally gets expelled out of the body during a bowel movement, just like waste material.
For many people, they will notice when the capsule leaves their body. However, sometimes a simple X-ray can be used to confirm if the capsule has successfully passed through the entire digestive system.
Why do People Need Capsule Endoscopy
A capsule endoscopy is a procedure used to look inside your digestive tract. This technique is commonly used when a person is experiencing unexplained bleeding in the gut and other tests like an upper and lower endoscopy couldn’t find the source. With a capsule endoscopy, doctors can detect the source of the bleeding about 35% to 77% of the time.
There are also several other reasons you might need a capsule endoscopy. These include diagnosing and evaluating the activity of Crohn’s disease, diagnosing celiac disease, monitoring for signs of polyps (small growths that could become cancerous), and inspecting tumors in the small intestine. A special type of capsule endoscopy can be used to check the esophagus for varicose veins, Barrett’s esophagus (a condition where the tissue lining the esophagus changes), and inflammation. A colon capsule endoscopy can help screen for colon cancer in patients with an incomplete prior colonoscopy, those with major risks for the procedure, or those who can’t tolerate sedation.
The Canadian Association of Gastroenterology provides some additional guidelines regarding capsule endoscopy. They recommend this procedure for patients suspected of having or experiencing a relapse of Crohn’s disease when other tests have been negative. However, they advise against using this technique for diagnosing celiac disease, but it could be helpful for patients with unexplained symptoms despite treatment. It’s worth pointing out that this association doesn’t recommend this procedure in patients experiencing only chronic abdominal pain or diarrhea without any evidence of markers associated with Crohn’s disease.
For those with clear bleeding symptoms and negative findings on an upper endoscopy and colonoscopy, a capsule endoscopy is highly encouraged to be performed as soon as possible. It may also be used for selected patients with chronic iron-deficiency anemia. For people who need to be monitored for polyp growth, the recommendation is to use capsule endoscopy. However, the colon capsule endoscopy should not be routinely substituted for a colonoscopy, especially in patients with inflammatory bowel disease.
When a Person Should Avoid Capsule Endoscopy
There are times when it’s not appropriate to use a health test called capsule endoscopy. This test involves swallowing a tiny camera inside a pill for taking pictures of your digestive system. Certain conditions or circumstances can make it difficult or unsafe to have this test.
For instance, people with dementia may find the test hard because it needs their cooperation. Similarly, people who have issues with swallowing may struggle to swallow the pill containing the camera.
People with heart devices, like pacemakers, defibrillators, or left ventricular assist devices, were once thought to be at risk for interference with their devices from the capsule, but no cases have actually been reported. Some research even says there’s no risk of interference at all. Still, not all medical centers feel comfortable doing the test on patients with these devices.
Pregnant women should also avoid the test, as there’s not enough research on whether it’s safe for them and their babies.
If the person has known or suspected digestive tract issues, like strictures (narrowing of the passageways), fistulas (abnormal connections between body parts), and blockages, the camera pill could get stuck, making the condition worse. In these cases, a different type of pill called an Agile Patency Capsule is used first. This pill does not have a camera and gets excreted from the body if not retained and dissolves if it is retained. If it’s seen to have passed through safely, the real endoscopy capsule can then be swallowed.
Some other issues like achalasia (difficulty swallowing), esophageal diverticula (pockets in the esophagus wall), esophageal strictures (narrowing of the esophagus), and pyloric stenosis (narrowing of the opening from the stomach to the intestine) can cause the pill to get stuck. Also, gastroparesis, which slows the movement of the stomach, can cause issues. In these cases, a tool called an AdvanCE Capsule Endoscopy Delivery System, attached to a gastroscope (a flexible tube with a light and camera), can be used to place the capsule in the stomach or small intestine. It’s also possible to use a tube or advanced from the stomach into the small intestine with nets and snares to help the capsule pass through safely.
Equipment used for Capsule Endoscopy
There are different types of pill-like cameras used in the United States for diagnosing medical conditions. Most are used to take pictures of your small intestine and capture 2 to 6 images every second. Some have a specific purpose of taking pictures of the inside of your esophagus, which is the tube that connects your throat to your stomach.
One type of these cameras, the PillCam ESO, has a battery life of 20 minutes and has a camera at both ends. It can take 18 images every second to give a good view of the esophagus. Another type of camera, the PillCam COLON, is used to take pictures of the inside of your colon. Just like the PillCam ESO, it has a camera at both ends. But this one turns on 2 hours after swallowing it to save battery life and allow for a full assessment of your colon.
The size of these pill-cameras may vary, but they’re generally about 1.1 by 1.6 cm in size, roughly as big as a large pill. The colon camera is a bit larger, measuring 1.1 by 3.2 cm. These cameras send data to a device you wear on your body using very high frequency radio waves or electrical signals. A computer loaded with specialized software is then used to view the images and make sense of the data. The software can also identify possible places where you might be bleeding by looking for images with red pixels.
Who is needed to perform Capsule Endoscopy?
A medical assistant or nurse, who have been trained in clinics or hospitals, can help a patient prepare for a capsule endoscopy. This involves swallowing a tiny camera (the capsule) that transmits pictures of your digestive tract. The nurses ensure that the easy-to-wear device (the external receiver) that collects these pictures is fit on the patient properly and also guide the patient through the process of swallowing the capsule.
After the tiny camera transmits the pictures, they are transfered, or downloaded, onto a computer. A gastroenterologist, who is a doctor specializing in the digestive system, then looks at these images. They are trained to examine internal images of your body (endoscopy) and point out any problems. They then write down their observations in a report to help understand your condition better.
Creating this report typically takes between 30 minutes to 2 hours if the camera is capturing images of the small intestine. If the camera is capturing pictures of the esophagus (the tube that connects your mouth to your stomach), this process generally takes between 5 to 15 minutes. This is the same amount of time a gastroenterologist usually takes to go through the images.
Preparing for Capsule Endoscopy
Getting ready for a capsule endoscopy is quite similar to getting ready for a colonoscopy and it can be done in a medical facility outside the hospital. On the day before the procedure, you should only consume clear liquids. You also need to avoid eating or drinking anything for 10 to 12 hours before you swallow the capsule that will take the pictures of your digestive tract.
In addition to this, a solution containing polyethylene glycol might be prescribed for you to drink the night before. This helps to flush out any leftover food and waste in your digestive system, improving the visibility for the camera in the capsule.
With a colon capsule endoscopy, which focuses on imaging your large intestine, or colon, you’ll be required to drink at least 3 liters of a similar solution to clear your bowel.
There are differing opinions about whether medicines like metoclopramide and erythromycin help with the movement of the camera capsule through your digestive system. Another type of solution, containing simethicone, can be used to get better pictures by reducing any air bubbles present in the food canal.
Remember to follow all the instructions your doctor or healthcare provider gives you strictly, this will make the procedure more successful, and valuable information about your digestive health can be gathered.
How is Capsule Endoscopy performed
Before swallowing a tiny video capsule, a patient has to wear a belt fitted with sensors. These sensors will pick up the images transmitted by the video capsule. The capsule is activated by removing a magnet, and can then be swallowed while the patient is standing or sitting up. There’s also an alternate way to place the capsule – it can be inserted into the stomach or first part of the small intestine (known as the duodenum) through a procedure called endoscopy.
After swallowing the capsule, the patient needs to avoid any activities that might cause the sensor belt to come off. They can start drinking clear liquids like water or broth two hours after swallowing the capsule, and eat a small meal four hours after swallowing the capsule.
If the capsule is meant to examine the esophagus (the tube that connects your mouth to your stomach), the patient needs to avoid eating or drinking for two hours before the procedure. They will also need to drink 100 mL (about half a cup) of water just before swallowing the capsule. Then, they will lie down flat, swallow the capsule, and slowly sit up over about five minutes.
Possible Complications of Capsule Endoscopy
Capsule endoscopy is a procedure where a small, pill-like camera is swallowed to take pictures of your digestive tract. While it’s considered pretty safe, about 1.3% to 1.4% of people might have the capsule get stuck, or “retained”. This is the most common problem we encounter. Two weeks after the procedure, if the capsule gets stuck, it’s often discovered through a plain x-ray of the belly. This condition usually doesn’t produce symptoms.
If we already know or suspect you have obstructions (blockages), narrow areas (strictures), or abnormal connections within the digestive tract (fistulas), we might decide not to use capsule endoscopy, because these conditions increase the chance of the capsule getting stuck. If you have Crohn’s disease, a condition that causes inflammation in the digestive tract, your risk of capsule retention increases to 2.6%.
Before doing a capsule endoscopy, we sometimes use a dummy pill called an Agile Patency Capsule to check whether there’s enough space in your bowel (intestinal lumen) for the capsule to travel safely. We might also use other imaging tests, like a small-bowel follow-through, a CT scan, or magnetic resonance enterography to check this.
If you have symptoms indicating that the capsule is stuck, we might need to remove it either through a minimally invasive procedure (endoscopy) or through surgery. It’s also possible for the capsule to get stuck in areas known as a Zenker or Meckel’s diverticulum.
Also, while it’s rare, there is a small risk that the capsule might be accidentally inhaled into the lungs (aspiration) or get stuck in the upper throat, an area called the cricopharyngeus.
What Else Should I Know About Capsule Endoscopy?
Capsule endoscopy is a technique used to inspect the digestive system, particularly when conventional methods have not worked. It’s a safe procedure that has no pain, no risk of infection, and doesn’t require patients to be sedated. Compared to many other methods, this technique can often give doctors a better idea of what’s going on inside a patient’s intestines and can pinpoint the locations of issues.
However, capsule endoscopy does have a key limitation – it doesn’t allow doctors to treat issues they might discover. While this kind of endoscopy does have a high success rate when it comes to diagnosis and a low rate of complications, it unfortunately can’t be used to take tissue samples or provide treatment.
Another factor to consider is that we’re still unsure about how cost-effective capsule endoscopy is. As healthcare costs continue to increase and patients often have to contribute a large portion of the costs themselves, the decision to use this kind of endoscopy has to be carefully thought-through.
Moreover, quality clinical data demonstrating the benefits of capsule endoscopy is so far lacking. The procedure’s effectiveness may vary depending on the patient’s condition. In cases of unknown internal bleeding, for example, the results might not be very informative. Some research has also indicated that capsule endoscopy might miss certain issues in the small intestine. Therefore, this technique is likely to be most useful when combined with other imaging methods, and should not be the first test used to investigate internal bleeding.
