Hospital tests
You may be referred to hospital for further tests such as a colonoscopy, if you've visited your GP with symptoms of bowel cancer or if your screening test found blood in your poo. This is to find out what is causing your symptoms.
We understand that it can be worrying waiting for a hospital appointment and not knowing what to expect. This page will explain the different tests that you may be offered at the hospital and how you can prepare for them.
Watch the video above to hear members of our community talk about what it's like to have a colonoscopy.
What test will I be given at the hospital?
The specialists at the hospital may decide that you need either an endoscopy or a virtual colonoscopy. You can find out more about these tests below.
Endoscopy
An endoscopy is a test that uses a small thin tube with a camera to look inside the body. There are lots of different types of endoscopy. Usually you’ll have either a flexible sigmoidoscopy or a colonoscopy to look inside your bowel. These tests are done by highly trained medical professionals, called endoscopists.
What is flexible sigmoidoscopy?
Flexible sigmoidoscopy looks inside the rectum (back passage) and the lower part of the large bowel (sigmoid colon). This is where most polyps (non-cancerous growths) and bowel cancers start. A long flexible tube with a bright light and a tiny camera on the end is inserted through your rectum (back passage). The tube also blows gas into your bowel to inflate it, which allows the endoscopist to get a clear view of the bowel lining. If the endoscopist sees anything that needs to be looked at more closely, samples (biopsies) can be taken for further tests in the laboratory.
Before having a flexible sigmoidoscopy your bowel will be cleaned out to allow endoscopist to see the bowel lining clearly. For a flexible sigmoidoscopy you will usually receive an enema (medicine given straight into the back passage) on the day of the test.
A flexible sigmoidoscopy usually takes around 15 minutes. You’ll likely be in the hospital for around two hours in total. This includes the time to prepare you for the test and the time after the test where the healthcare team will check that you are fit and well to go home.
What is a colonoscopy?
A colonoscopy looks at the lining of your whole large bowel, to see if there are polyps or a cancer within any part of it. A long flexible tube with a bright light and a tiny camera on the end is inserted through your rectum (back passage). The tube also blows gas into your bowel to inflate it, which allows the endoscopist to get a clear view of the bowel lining. During the test, if the endoscopist sees anything that needs further investigation, photographs and samples (biopsies) can be taken. Simple polyps can be removed during a colonoscopy.
If you've been referred for a colonoscopy you may be seen by a specialist nurse or screening practitioner, have a telephone call or be sent instructions in the post. You’ll be asked about any medical conditions to make sure it’s safe for you.
Before you have a colonoscopy, the bowel needs to be cleaned out. You’ll be given a medicine to drink, known as a laxative. This will make you go to the toilet more often. You may also need to make some changes to your diet for a few days before your colonoscopy.
A colonoscopy usually takes around 30 to 45 minutes. You’ll likely be in the hospital for around two hours in total. This includes the time to prepare you for the test and the time after the test where the healthcare team will check that you're fit and well to go home.
What is colon capsule endoscopy?
Colon capsule endoscopy isn’t widely available yet, but it’s being tested out across a selection of hospitals in England, Scotland and Wales.
A colon capsule endoscopy involves swallowing a small camera that's about the size of a large vitamin pill. As the capsule travels through your bowel it takes thousands of pictures that are sent to a recording device.
On the day of having a colon capsule endoscopy, a specialist nurse will check that you're ready and fit you with a belt and a shoulder bag that holds the recording device. These can be worn under your clothes so you may want to wear loose clothing to your appointment. You’ll wear the belt and recorder during the whole test, which can take around six to eight hours. You’ll be given the capsule to swallow with a glass of water. You can then go home. The belt and bag with the recorder may be quite heavy for some people, so you may want to arrange transport home from your appointment.
Throughout the day, you may be asked to take medicine, called laxatives, to help the capsule move through your bowel. You should try to move around as much as possible to help the capsule move.
Once the capsule has passed through your bowel, it will come out when you go for a poo. It can be flushed down the toilet. You can then remove the belt and recorder. You’ll be asked to return these to the hospital on the same day, or the next day.
The pictures are checked by a specialist doctor called a colonoscopist. If the pictures show anything that needs to be checked, you may be referred for further tests, such as a colonoscopy.
For about five days before having a colon capsule endoscopy, you’ll need to follow a low fibre diet. You’ll be given information about this by your specialist nurse. On the day before the test, you’ll be given medication to drink, known as a laxative. This will make you go to the toilet more often and will clean out your bowel so the capsule can take clear images during the test.
On the morning of the test, you’ll be in the hospital for around an hour. This time will be spent explaining the test and the instructions you need to follow, and giving you the capsule to swallow. After swallowing the capsule, you’ll be asked to stay in the hospital until it has left your stomach. The test itself usually takes around six to eight hours and you can usually go home during this time.
Virtual colonoscopy
Virtual colonoscopy (also known as CT colonography) involves using a CT scanner to look at the large bowel and rectum. The following information will provide more detail on what this test involves, including what you might need to do to prepare.
What is a virtual colonoscopy?
Virtual colonoscopy (also known as CT colonography) involves using a CT scanner to produce two and three dimensional images of the large bowel and rectum. This can be used for patients who are not suitable for regular colonoscopy due to other medical reasons. Virtual colonoscopies are not currently available in every hospital, so you may need to travel to have this test.
A virtual colonoscopy can detect shape changes such as polyps within the bowel. However, it can’t easily spot flat areas of inflammation or changes in the lining of the bowel. It also can’t take samples or remove polyps in the same way as flexible sigmoidoscopy or colonoscopy, so you may still need to have this too.
A radiographer or a specialist doctor known as a radiologist will do the virtual colonoscopy. During the test, gas is used to inflate the bowel via a thin flexible tube placed in your rectum (back passage). You’ll be asked to lie on your back, then on your front while the CT scans are taken. This allows the radiographer or radiologist to get a clear set of scans of your bowel. You’ll be asked to hold your breath for approximately 20 seconds in both positions.
The bowel needs to be empty so that the radiographer or radiologist can see inside clearly. On the day before the test, you’ll be given medication, known as a laxative, which will make you go to the toilet more often. Or you may be given a liquid called a contrast medium to drink. This is a dye which helps to make the images from the CT scan clearer. It also acts as a laxative. You may also need to follow a low fibre diet for a few days before the test. Your healthcare team will provide you with information about this.
A virtual colonoscopy usually takes around 30 minutes. You’ll likely be in the hospital for around an hour in total. After the test, you’ll be asked to stay for a short time so that the healthcare team can check that you’re ready to go home.
Making you comfortable
If you're nervous about having an endoscopy or a virtual colonoscopy, talk to your healthcare team. It may be possible to be sedated during the test. If you have problems lying flat on your back or lying on your side to have the test done, let your healthcare team know so that arrangements can be made.
After a colonoscopy, the gas that was used to inflate the bowel can sometimes cause discomfort in your abdomen (tummy area) or shoulders. Chewing peppermint gum, drinking warm peppermint tea, massaging your abdomen or walking about can help to relieve any discomfort and help the gas pass out of your body.
Waiting for test results
Ask your healthcare team when you can expect to find out the results and whether you’ll be invited to an appointment, told over the phone or by letter.
If the tests show that you have bowel cancer, your healthcare team will talk to you about what happens next.
If your test results show that you don’t have bowel cancer, you’ll either be referred back to your GP, or you may be sent for different tests or treatments for other medical conditions.
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