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What is an endoscopy?

A diagnostic endoscopy is a procedure performed to look at the inside of your body.

The examination is carried out using a long, thin flexible tube that has a camera and light source on one end, called an endoscope. Images of the inside of your body are sent to a television screen for your doctor to see. An endoscope is inserted into your body through a natural opening of your mouth or bottom so you don’t need any cuts.

Sometimes an endoscope is used for treatment by passing instruments down it as needed. For keyhole surgery, it might be necessary to pass an endoscope through an incision in your skin.

When is an endoscopy used?

Your doctor will recommend an endoscopy to:

  • Investigate any unusual symptoms you may be experiencing. It allows your doctor to see what is happening inside your body and they may perform a biopsy to remove a small sample of tissue for further analysis that will help them make a diagnosis.
  • Help gain access to internal organs for surgical procedures.

What symptoms is an endoscopy used to investigate?

Symptoms when a diagnostic endoscopy may be recommended include:

  • enduring abdominal pain
  • dysphagia - difficulty swallowing
  • chest pain not caused by heart-related conditions
  • persistent nausea and vomiting
  • vomiting blood
  • long lasting diarrhoea
  • unexplained weight loss
  • blood in your stools

Types of endoscopies

There are different types of endoscopies used for different areas of the body. The most common ones include:


Also known as an upper gastrointestinal endoscopy, a gastroscopy is used to look inside your oesophagus, stomach and upper part of your small intestine (duodenum).

It investigates symptoms including: indigestion, heartburn, continued abdominal pain, persistent vomiting, vomiting blood, difficulty swallowing, unexplained weight loss, and anaemia.

It diagnoses conditions including: stomach ulcers, gastro-oesophageal reflux disease (GORD) and Barrett's oesophagus, coeliac disease, and early signs of cancer.

It can be used to treat some conditions such as: a blocked oesophagus, a bleeding ulcer, a polyp and small cancerous tumours.

A diagnostic gastroscopy is a 15-minute outpatient procedure, performed usually under local anaesthetic. The endoscope is passed through your mouth and into your stomach. Gastroscopy treatment, known as therapeutic gastroscopy, takes longer.


Enteroscopy allows your doctor to see inside your small bowel, the area between your stomach and the large intestine. The enteroscope is passed through your mouth, down your GI tract and into your small intestine.

It is used to: diagnose and treat hidden gastrointestinal bleeding, find out what is causing digestive problems such as malabsorption, look into frequent or persistent diarrhoea that has no obvious cause, to confirm diagnoses made of the small intestine by CT, MRI or x-ray, and for biopsies of lesions.

An enteroscopy is a 45-minute procedure usually performed under local anaesthetic.

Capsule Endoscopy

Capsule endoscopy is a disposable capsule of pill size that is easy to swallow so you won’t need a sedative. It contains a camera and can film all of your small intestine. After the initial set up, you can complete the ten-hour procedure at home.

A capsule endoscopy is a relatively new procedure that can be used to diagnose: Crohn’s and Coeliac disease, polyps or tumours, iron-deficiency anaemia caused by bleeding in the small intestine, the reason for chronic diarrhoea and weight-loss. It can also confirm small intestine abnormalities that have been found in CT and MRI scans, or barium tests.


A colonoscopy is used to see inside your colon including your bowel and rectum.

It investigates symptoms such as: lower abdomen pain, bleeding from your back passage, ongoing diarrhoea, and other symptoms thought to be resulting from your colon.

It can diagnose conditions including: diverticulitis, inflammatory bowel diseases such as Ulcerative colitis and Crohn's disease, bowel polyps and bowel cancer.

A colonoscopy is a 30-minute day case procedure usually performed under local anaesthetic. The endoscope is inserted through your back passage. Sometimes a biopsy is taken for further analysis.

Flexible sigmoidoscopy

A flexible sigmoidoscopy is used to examine the lower part of your large intestine, known as the sigmoid colon.

It’s a 15-minute outpatient procedure where the sigmoidoscope is inserted through your back passage to take images of your colon. It is also used to take biopsies, remove polyps and as part of the bowel cancer screening programme.


A bronchoscopy is used to examine your airways and lungs.

It investigates a persistent cough or if you're coughing up blood. It can help your doctor to see tumours and to perform biopsies.

A bronchoscopy can treat: bleeding from a tumour and the narrowing of an airway due to a tumour. It can be used to remove a small object that has been lodged in an airway and to insert a small tube called a stent to open a collapsed airway.

The bronchoscope is passed through your mouth and down through your trachea into the large airways of your lungs, called bronchial tubes. It’s a 30-minute outpatient procedure usually performed under local anaesthetic.


A hysteroscopy is used to examine the inside of your womb (uterus).

It can investigate: irregular and heavy periods, postmenopausal bleeding, pelvic pain, repeated miscarriages and fertility problems.

It can diagnose conditions including: fibroids and polyps (non-cancerous growths).

It can be used to remove: fibroids, polyps, displaced intrauterine devices (IUDs) and scar tissue that is causing absent periods and reduced fertility, known as intrauterine adhesions.

A hysteroscopy is carried out by passing a hysteroscope into your womb through your vagina and cervix. It’s an outpatient procedure that can take five to 30 minutes. Local anaesthetic may be used for diagnostic procedures or general anaesthetic if you’re having treatment.


A cystoscopy is used to examine the inside of your bladder.

It can investigate problems such as urinary incontinence, blood in your urine, frequent urinary tract infections (UTIs), problems urinating, and long-lasting pelvic pain.

It can diagnose conditions ranging from cystitis to bladder cancer.

It can be used to remove bladder stones, insert or remove a stent and to inject medication into your bladder.

A cystoscopy is carried out by passing a cystoscope through your urethra (the tube that runs from your bladder to the outside of your body) and into the bladder. Your doctor can take a biopsy or pass small surgical instruments down to your bladder to treat bladder problems at the same time as performing diagnostic cystoscopy, if required. Diagnostic cystoscopy can be performed in a matter of minutes.


Laparoscopy uses a type of endoscope called a laparoscope that acts as a visual aid for your doctor to investigate and diagnose many conditions of your abdomen and pelvis.

It is used in keyhole surgery, also known as laparoscopic surgery, as it requires only small incisions. Laparoscopic surgery is less invasive and offers faster recovery time, less pain and bleeding than open surgery.

Laparoscopic surgery is most often used in gynaecology, gastroenterology and urology patients. It can remove: a gallbladder, an appendix, a section of intestine, the womb, an organ affected by cancer, and repair hernias.

A diagnostic laparoscopy usually takes 30 to 60 minutes. When treating a condition, the procedure will take longer and will depend on the surgery being performed. Laparoscopy is carried out under general anaesthetic.

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