The endoscope can also be used for enabling biopsies and retrieving foreign objects.
Endoscopy is a noninvasive alternative to surgery for foreign object removal from the gastrointestinal tract.
When is an endoscopy used?To confirm a diagnosis
An endoscopy is often used to confirm a diagnosis when other devices, such as an MRI, X-ray, or CT scan are considered inappropriate.
An endoscopy is often carried out to find out the degree of problems a known condition may have caused. The endoscopy, in these cases, may significantly contribute towards the doctor's decision on the best treatment for the patient.
The following conditions and illnesses are most commonly investigated or diagnosed with an endoscopy:
- Breathing disorders
- Chronic diarrhea
- Internal bleeding
- Irritable bowel syndrome
- Stomach ulcers
- Urinary tract infections.
Endoscopies are commonly used for the diagnosis of cancer. They are used for biopsies - taking samples of tissue to find out whether it is cancerous. Thanks to an endoscope, biopsies of the intestines or lungs can be done without the need for major surgery. This study explains that colonoscopy is the most effective screening option for colorectal cancer.
Some surgical procedures can be carried out with a modified endoscope, such as the removal of the gallbladder, tying and sealing the fallopian tubes, and taking out small tumors and foreign objects from the lungs or digestive system. A study found that the removal through endoscopy of tumors that affect only the superficial layers of the esophagus can avoid complete extirpation of this part of the digestive tract.
A study carried out by the 3M Infection Inspection Division found that 3 in every 20 endoscopes had unacceptable levels of "bio dirt".
Short history of endoscopyReports indicate that the first endoscope was devised in 1805. It consisted of a large tube and a candle. Because it was cumbersome and large it had very limited uses. Fiber optics, which appeared in the 1960s, was a major factor in the endoscopy revolution. With fiber optics it really became possible for the doctor to see and record the inside of the patient's body with a small and relatively painless device.
Endoscopy has many uses todayAn endoscope can be fitted with surgical instruments; it can send pulses or heat and electricity and destroy small tumors or gallstones. Specialized endoscopes have their own names, such as:
- Bronchoscopes - they examine the air passages and the lungs.
- Colonoscopes - they examine the colon.
- Gastroscopes - they examine the small intestine, stomach and esophagus (throat).
- Arthroscopes - they examine the joints.
- Hysteroscopes - they examine a woman's uterus.
- Cystoscopes - they examine the urinary bladder.
Types of endoscopiesHere is a list of some types of endoscopies and their meanings:
- Amnioscopy - examination of the amniotic cavity and fetus.
- Arthroscopy - examination of the joints.
- Bronchoscopy - examination of the air passages and the lungs.
- Colonoscopy - examination of the colon.
- Colposcopy - examination of the cervix and the tissues of the vagina and vulva.
- Cystoscopy - examination of the urinary bladder.
- EGD (Esophageal Gastroduodenoscopy), also known as panendoscopy - examination of the esophagus, stomach and duodenum.
- ERCP (endoscopic retrograde cholangio-pancreatography) - examination of the liver, gallbladder, bile ducts, and pancreas.
- Fetoscopy - examination of the fetus.
- Laparoscopy - a small incision to examine the abdominal cavity.
- Laryngoscopy - examination of the back of the throat, including the voice box (larynx) and vocal cords.
- Proctoscopy - examination of the rectum and the end of the colon.
- Rhinoscopy - examination of the inside of the nose.
- Thoracoscopy - examination of the lungs or other structures in the chest cavity.
The patient swallows a capsule which wirelessly sends images of the inside of his/her stomach and digestive tract. Eventually the capsule will exit the patient when he/she has a bowel motion. Currently, capsule endoscopy is used to find out why a patient is bleeding in their digestive system, with no clear cause. It can also be used to diagnose GERD (Gastroesophageal reflux disease). A study indicated that capsule endoscopy is effective in diagnosing gastrointestinal bleeding and small bowel Crohn's disease in children. Another study showed how wireless capsule endoscopy is turning up Crohn's diseases diagnoses among patients whose illness had not been spotted for over a decade.
The capsule is about the size of a multi-vitamin and has a camera attached to it. As it moves through the digestive tract it takes pictures. The patient wears a small data recorder on his/her belt; this recorder receives the data from the capsule. The pictures are later downloaded and interpreted by a doctor.
Before swallowing the capsule the patient must have fasted overnight. The next day he/she will be fitted with the equipment, which includes a belt that contains a battery and a data recorder. Leads will be hooked up to the abdomen; this is painless and does not perforate the skin. As soon as the equipment is hooked up the patient swallows the capsule. Eight hours later he/she returns and the equipment is disconnected.
The main components of an endoscopeAn endoscope consists of:
- A flexible or rigid tube.
- A light that illuminates what the doctor wants to examine. The light is delivered via an optical fiber system.
- A lens system that transmits an image to the viewer from the fiberscope.
- Another channel to allow the entry of medical instruments or manipulators.
What happens during an endoscopy?The patient may be asked to fast (not eat) or drink for a period before the endoscopy if the instrument is going to go in through the anus. In some cases the patient may be given a laxative. Some patients are given antibiotics to prevent infection.
Patients on blood-thinning medications, such as warfarin, may be asked to stop taking them for a number of days before their endoscopy. There is a risk the blood thinner may cause excessive bleeding during the procedure. It is important the patient only does so if the doctor tells him/her. A study concluded that anti-inflammatory drugs, such as aspirin, do not increase the patient's risk of bleeding during an endoscopy.
In the UK most endoscopies are done in hospital, or some large GP (general practice) clinics.
The vast majority of endoscopies do not require a general anesthetic. Some patients may receive a local anesthetic. A study found that administering a lidocaine lollipop as a single-agent anesthetic to patients undergoing an upper gastrointestinal endoscopy procedure eliminated the need for sedation in the majority of patients. Patients describe the procedure as possibly 'uncomfortable', but hardly ever 'painful'. This study explains that the use of an evidence-based sedation protocol for endoscopic procedures improves the quality of practice and reduces the incidence of sedation-related adverse events.
Most endoscopes will enter the patient via the:
- Urethra (urine exits the body through the urethra)
- A small incision made in the skin.
Most patients can get up within an hour of their endoscopy. It is advisable that the patient does not drive out of the hospital after an endoscopy.
What are the complications of an endoscopy?According to the National Health Service (NHS), UK, less than 1% of endoscopies have complications. When they do occur, they may include:
- An infection, possibly somewhere along the path of the endoscope.
- Piercing or tearing of an organ. This may require subsequent surgery. This article explains how tears and perforations caused by endoscopy can be fixed without invasive surgery.
- Bleeding more than normally expected. This may require subsequent surgery.
- An allergy to the anesthetic. Antihistamines may be used to treat this.
Sources: National Health Service (NHS), UK, The Mayo Clinic, Wikipedia, HHS (Department of Health and Human Services USA), NIH (National Institutes of Health, USA).
Written by Christian Nordqvist