Colonoscopy

Understanding Colonoscopy: A summary by Mike Williamson

As a Consultant Colorectal Surgeon, I regularly see patients with bowel-related symptoms. I understand that talking about bowel problems can feel uncomfortable, but it is incredibly important to seek medical advice if you notice any of the following:
•    A persistent change in your usual bowel habits
•    Blood in your stool
•    Ongoing abdominal discomfort or other unusual symptoms

Why Early Action Matters

Catching bowel issues early makes treatment easier and more effective. If something doesn’t feel right, don’t wait - speak to your GP or a specialist.

What is a colonoscopy?

A colonoscopy is a procedure used to examine the inside of the large bowel (colon) using a flexible tube with a camera. It allows your doctor to directly view the bowel lining, identify abnormalities, and take samples if needed.
Although scans like CT and MRI are useful for many conditions, they can’t always detect bowel issues as well as a colonoscopy can. A colonoscopy is the most accurate way to check for causes of bowel symptoms and is often called the “gold standard” of bowel investigations.

What Can a Colonoscopy Detect?

• Polyps: These are small, fleshy growths that can sometimes turn into cancer. A colonoscopy allows us to spot and remove them during the same procedure.
• Inflammation or signs of disease: We can take a small tissue sample (biopsy) if we see anything unusual. This is painless and helps with diagnosis.
• Early bowel cancer: Early detection greatly improves outcomes.

Are Enough Colonoscopies Being Done?

Unfortunately, we’re not doing as many colonoscopies in the UK as we should be. Here's why:
•    The National Bowel Cancer Screening Programme that does exist uses a stool test to check for hidden blood in your poo between the ages of 55 and 74, but this misses many polyps and some cancers.
•    There is currently no national screening programme offering full colonoscopies to the general population.

Most people are only referred for a colonoscopy if they have symptoms or a strong family history of bowel cancer. During a private consultation, we can discuss the risks and benefits of having a colonoscopy if you have only a weak family history, or even if you do not have any history or symptoms but would like to reduce your risk of developing bowel cancer.
 

What Happens During a Colonoscopy?

Preparation the Day Before

To get a clear view, your bowel must be empty. You’ll be given a special drink (a bowel prep) the day before, which causes frequent trips to the toilet. Most people find this the hardest part of the process - but it is essential for a good result.

The Procedure

The procedure itself usually takes 15 - 20 minutes:
•    A thin, flexible tube (colonoscope) is passed into the bowel through the anus.
•    The camera shows detailed images of the bowel lining.
•    We can take biopsies or remove polyps at the same time if needed.

Comfort and Sedation Options

Some people find the procedure uncomfortable, while others manage well without sedation. You can choose between:
•    Entonox (laughing gas)
•    Sedation via a canula placed in an arm vein (usually a combination of a painkiller and a sedative)

If you choose sedation, you’ll need someone to take you home and look after you that evening.

Can I help?

If you’ve been advised to have a colonoscopy - or are just concerned about symptoms you’ve noticed - getting expert advice can make a big difference.
At your consultation, I will talk through your symptoms, your relevant medical history, and any worries you may have. If I believe a colonoscopy will help, I can arrange to do it for you here at Sulis Hospital Bath.

Booking an Appointment

If you’d like to discuss whether a colonoscopy is right for you, please contact my private secretary, who will be happy to arrange an appointment at a convenient time.