Esophagogastroduodenoscopy (EGD) or oesophagogastroduodenoscopy (OGD), also called by
various other names, is a
diagnostic
Diagnosis is the identification of the nature and cause of a certain phenomenon. Diagnosis is used in many different disciplines, with variations in the use of logic, analytics, and experience, to determine " cause and effect". In systems engine ...
endoscopic
An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are insert ...
procedure that visualizes the upper part of the
gastrointestinal tract
The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organ (biology), organs of the digestive syste ...
down to the
duodenum
The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine m ...
. It is considered a
minimally invasive procedure
Minimally invasive procedures (also known as minimally invasive surgeries) encompass surgical techniques that limit the size of incisions needed, thereby reducing wound healing time, associated pain, and risk of infection. Surgery by definition ...
since it does not require an
incision into one of the major body cavities and does not require any significant recovery after the procedure (unless
sedation
Sedation is the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure. Examples of drugs which can be used for sedation include isoflurane, diethyl ether, ...
or
anesthesia
Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prevention of pain), paralysis (muscle relaxation), ...
has been used). However, a
sore throat
Sore throat, also known as throat pain, is pain or irritation of the throat. Usually, causes of sore throat include
* viral infections
* group A streptococcal infection (GAS) bacterial infection
* pharyngitis (inflammation of the throat)
* tonsi ...
is common.
Alternative names
The words ''esophagogastroduodenoscopy'' (EGD;
American English
American English, sometimes called United States English or U.S. English, is the set of variety (linguistics), varieties of the English language native to the United States. English is the Languages of the United States, most widely spoken lan ...
) and ''oesophagogastroduodenoscopy'' (OGD;
British English
British English (BrE, en-GB, or BE) is, according to Lexico, Oxford Dictionaries, "English language, English as used in Great Britain, as distinct from that used elsewhere". More narrowly, it can refer specifically to the English language in ...
; see
spelling differences
Despite the various English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American ...
) are both pronounced . It is also called ''panendoscopy'' (PES) and ''upper GI endoscopy''. It is also often called just ''upper endoscopy'', ''upper GI'', or even just ''endoscopy''; because EGD is the most commonly performed type of endoscopy, the ambiguous term ''endoscopy'' is sometimes informally used to refer to EGD by default. The term ''gastroscopy'' literally focuses on the stomach alone, but in practice, the usage overlaps.
Medical uses
Diagnostic
* Unexplained
anemia
Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
(usually along with a
colonoscopy
Colonoscopy () or coloscopy () is the endoscopic examination of the large bowel and the distal part of the small bowel with a CCD camera or a fiber optic camera on a flexible tube passed through the anus. It can provide a visual diagnosis (''e. ...
)
*
Upper gastrointestinal bleeding
Upper gastrointestinal bleeding is gastrointestinal bleeding in the upper gastrointestinal tract, commonly defined as bleeding arising from the esophagus, stomach, or duodenum. Blood may be observed in vomit or in altered form as black stool. D ...
as evidenced by
hematemesis
Hematemesis is the vomiting of blood. It is always an important sign. It can be confused with hemoptysis (coughing up blood) or epistaxis (nosebleed), which are more common. The source is generally the upper gastrointestinal tract, typically abo ...
or
melena
Melena or melaena refers to the dark black, tarry feces that are associated with upper gastrointestinal bleeding. The black color and characteristic strong odor are caused by hemoglobin in the blood being altered by digestive enzymes and intest ...
* Persistent
dyspepsia
Indigestion, also known as dyspepsia or upset stomach, is a condition of impaired digestion. Symptoms may include upper abdominal fullness, heartburn, nausea, belching, or upper abdominal pain. People may also experience feeling full earlier t ...
in patients over the age of 45 years
* Heartburn and chronic acid reflux – this can lead to a precancerous lesion called
Barrett's esophagus
Barrett's esophagus is a condition in which there is an abnormal (metaplastic) change in the mucosal cells lining the lower portion of the esophagus, from stratified squamous epithelium to simple columnar epithelium with interspersed goblet cells ...
* Persistent emesis
*
Dysphagia
Dysphagia is difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, in some contexts it is classified as a disease#Terminology, condition in its own right.
It may be a sensation that suggests difficulty in the passag ...
– difficulty in swallowing
*
Odynophagia
Odynophagia is pain when swallowing. The pain may be felt in the mouth or throat and can occur with or without difficulty swallowing. The pain may be described as an ache, burning sensation, or occasionally a stabbing pain that radiates to the b ...
– painful swallowing
* Persistent
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
* IBD (
inflammatory bowel disease
Inflammatory bowel disease (IBD) is a group of inflammation, inflammatory conditions of the colon (anatomy), colon and small intestine, Crohn's disease and ulcerative colitis being the principal types. Crohn's disease affects the small intestine a ...
s)
Surveillance
* Surveillance of
Barrett's esophagus
Barrett's esophagus is a condition in which there is an abnormal (metaplastic) change in the mucosal cells lining the lower portion of the esophagus, from stratified squamous epithelium to simple columnar epithelium with interspersed goblet cells ...
* Surveillance of
gastric ulcer
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines i ...
or
duodenal ulcer
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines ...
* Occasionally after gastric surgery
Confirmation of diagnosis/biopsy
* Abnormal
barium swallow
An upper gastrointestinal series, also called a barium swallow, barium study, or barium meal, is a series of radiographs used to examine the gastrointestinal tract for abnormalities. A contrast medium, usually a radiocontrast agent such as barium ...
or
barium meal
An upper gastrointestinal series, also called a barium swallow, barium study, or barium meal, is a series of radiographs used to examine the gastrointestinal tract for abnormalities. A contrast medium, usually a radiocontrast agent such as ba ...
* Confirmation of
celiac disease
Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barl ...
(via biopsy)
Therapeutic
* Treatment (banding/sclerotherapy) of esophageal varices
* Injection therapy (e.g.,
epinephrine
Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...
in bleeding lesions)
* Cutting off of larger pieces of tissue with a
snare device (e.g.,
polyps
A polyp in zoology is one of two forms found in the phylum Cnidaria, the other being the medusa. Polyps are roughly cylindrical in shape and elongated at the axis of the vase-shaped body. In solitary polyps, the aboral (opposite to oral) end i ...
, endoscopic mucosal resection)
* Application of
cautery
Cauterization (or cauterisation, or cautery) is a medical practice or technique of burning a part of a body to remove or close off a part of it. It destroys some tissue in an attempt to mitigate bleeding and damage, remove an undesired growth, or ...
to tissues
* Removal of
foreign bodies
A foreign body (FB) is any object originating outside the body of an organism. In machinery, it can mean any unwanted intruding object.
Most references to foreign bodies involve propulsion through natural orifices into hollow organs.
Foreign bo ...
(e.g., food) that have been ingested
* Tamponade of bleeding
esophageal varices
Esophageal varices are extremely dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendency to develop ...
with a
balloon
A balloon is a flexible bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, and air. For special tasks, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or light so ...
* Application of photodynamic therapy for treatment of esophageal malignancies
* Endoscopic drainage of
pancreatic pseudocyst
A pancreatic pseudocyst is a circumscribed collection of fluid rich in pancreatic enzymes, blood, and non-necrotic tissue, typically located in the lesser sac of the abdomen. Pancreatic pseudocysts are usually complications of pancreatitis, altho ...
* Tightening the
lower esophageal sphincter
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...
* Dilating or stenting of
stenosis
A stenosis (from Ancient Greek στενός, "narrow") is an abnormal narrowing in a blood vessel or other tubular organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture).
''Stricture'' ...
or
achalasia
Esophageal achalasia, often referred to simply as achalasia, is a failure of smooth muscle fibers to relax, which can cause the lower esophageal sphincter to remain closed. Without a modifier, "achalasia" usually refers to achalasia of the esoph ...
*
Percutaneous endoscopic gastrostomy
Percutaneous endoscopic gastrostomy (PEG) is an endoscopic medical procedure in which a tube (PEG tube) is passed into a patient's stomach through the abdominal wall, most commonly to provide a means of feeding when oral intake is not adequate (fo ...
(feeding tube placement)
*
Endoscopic retrograde cholangiopancreatography
Endoscopic retrograde cholangiopancreatography (ERCP) is a technique that combines the use of endoscopy and fluoroscopy to diagnose and treat certain problems of the biliary or pancreatic ductal systems. It is primarily performed by highly skille ...
(ERCP) combines EGD with
fluoroscopy
Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and functio ...
*
Endoscopic ultrasound
Endoscopic ultrasound (EUS) or echo-endoscopy is a medical procedure in which endoscopy (insertion of a probe into a hollow organ) is combined with ultrasound to obtain images of the internal organs in the chest, abdomen and colon. It can be used ...
(EUS) combines EGD with 5–12 MHz
ultrasound
Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hea ...
imaging
Newer interventions
* Endoscopic trans-gastric laparoscopy
* Placement of
gastric balloon
A gastric balloon, also known as an intragastric balloon (IGB) or a stomach balloon, is an inflatable medical device that is temporarily placed into the stomach to help reduce weight. It is designed to help provide weight loss when diet and exerc ...
s in
bariatric surgery
Bariatric surgery (or weight loss surgery) includes a variety of procedures performed on people who are obese. Long term weight loss through the standard of care procedures ( Roux en-Y bypass, sleeve gastrectomy, and biliopancreatic diversion ...
Complications
The complication rate is about 1 in 1000.
They include:
* aspiration, causing
aspiration pneumonia
Aspiration pneumonia is a type of lung infection that is due to a relatively large amount of material from the stomach or mouth entering the lungs. Signs and symptoms often include fever and cough of relatively rapid onset. Complications may inclu ...
* bleeding
* perforation
* cardiopulmonary problems
When used in
infant
An infant or baby is the very young offspring of human beings. ''Infant'' (from the Latin word ''infans'', meaning 'unable to speak' or 'speechless') is a formal or specialised synonym for the common term ''baby''. The terms may also be used to ...
s, the esophagogastroduodenoscope may compress the
trachealis muscle
The trachealis muscle is a sheet of smooth muscle in the trachea.
Structure
The trachealis muscle lies posterior to the trachea and anterior to the oesophagus. It bridges the gap between the free ends of C-shaped rings of cartilage at the post ...
, which narrows the
trachea
The trachea, also known as the windpipe, is a Cartilage, cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. The trachea extends ...
.
This can result in reduced airflow to the
lung
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side of t ...
s.
Infants may be
intubated
Intubation (sometimes entubation) is a medical procedure involving the insertion of a tube into the body. Patients are generally anesthetized beforehand. Examples include tracheal intubation, and the balloon tamponade with a Sengstaken-Blakemo ...
to make sure that the trachea is fixed open.
Limitations
Problems of gastrointestinal ''function'' are usually not well diagnosed by endoscopy since ''motion'' or ''secretion'' of the gastrointestinal tract is not easily inspected by EGD. Nonetheless, findings such as excess fluid or poor motion of the gut during endoscopy can be suggestive of disorders of function.
Irritable bowel syndrome
Irritable bowel syndrome (IBS) is a "disorder of gut-brain interaction" characterized by a group of symptoms that commonly include abdominal pain and or abdominal bloating and changes in the consistency of bowel movements. These symptoms may ...
and
functional dyspepsia
Indigestion, also known as dyspepsia or upset stomach, is a condition of impaired digestion. Symptoms may include upper abdominal fullness, heartburn, nausea, belching, or upper abdominal pain. People may also experience feeling full earlier t ...
are not diagnosed with EGD, but EGD may be helpful in excluding other diseases that mimic these common disorders.
Procedure
The tip of the endoscope should be lubricated and checked for critical functions including tip angulations, air and water suction, and image quality.
The patient is kept
NPO (nil per os) or NBM (nothing by mouth) for at least 4 hours before the procedure. Most patients tolerate the procedure with only
topical anesthesia A topical anesthetic is a local anesthetic that is used to numb the surface of a body part. They can be used to numb any area of the skin as well as the front of the eyeball, the inside of the nose, ear or throat, the anus and the genital area. Topi ...
of the
oropharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struct ...
using
lidocaine
Lidocaine, also known as lignocaine and sold under the brand name Xylocaine among others, is a local anesthetic of the amino amide type. It is also used to treat ventricular tachycardia. When used for local anaesthesia or in nerve blocks, lidoca ...
spray. However, some patients may need sedation and the very anxious/agitated patient may even need a general anesthetic.
Informed consent
Informed consent is a principle in medical ethics and medical law, that a patient must have sufficient information and understanding before making decisions about their medical care. Pertinent information may include risks and benefits of treatme ...
is obtained before the procedure. The main risks are bleeding and perforation. The risk is increased when a biopsy or other intervention is performed.
The patient lies on their left side with the head resting comfortably on a pillow. A mouth-guard is placed between the teeth to prevent the patient from biting on the endoscope. The endoscope is then passed over the tongue and into the oropharynx. This is the most uncomfortable stage for the patient. Quick and gentle manipulation under vision guides the endoscope into the esophagus. The endoscope is gradually advanced down the esophagus making note of any pathology. Excessive
insufflation
In religious and magical practice, insufflation and exsufflation are ritual acts of blowing, breathing, hissing, or puffing that signify variously expulsion or renunciation of evil or of the devil (the Evil One), or infilling or blessing with goo ...
of the stomach is avoided at this stage. The endoscope is quickly passed through the stomach and through the
pylorus
The pylorus ( or ), or pyloric part, connects the stomach to the duodenum. The pylorus is considered as having two parts, the ''pyloric antrum'' (opening to the body of the stomach) and the ''pyloric canal'' (opening to the duodenum). The ''pylori ...
to examine the first and second parts of the
duodenum
The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine m ...
. Once this has been completed, the endoscope is withdrawn into the stomach and a more thorough examination is performed including a J-maneuver. This involves retroflexing the tip of the scope so it resembles a 'J' shape in order to examine the
fundus and gastroesophageal junction. Any additional procedures are performed at this stage. The air in the stomach is aspirated before removing the endoscope. Still
photograph
A photograph (also known as a photo, image, or picture) is an image created by light falling on a photosensitive surface, usually photographic film or an electronic image sensor, such as a CCD or a CMOS chip. Most photographs are now create ...
s can be made during the procedure and later shown to the patient to help explain any findings.
In its most basic use, the endoscope is used to inspect the internal anatomy of the digestive tract. Often inspection alone is sufficient, but
biopsy
A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...
is a valuable adjunct to endoscopy. Small biopsies can be made with a pincer (biopsy
forceps
Forceps (plural forceps or considered a plural noun without a singular, often a pair of forceps; the Latin plural ''forcipes'' is no longer recorded in most dictionaries) are a handheld, hinged instrument used for grasping and holding objects. Fo ...
) which is passed through the scope and allows sampling of 1 to 3 mm pieces of tissue under direct vision. The intestinal mucosa heals quickly from such biopsies.
Equipment
![Indigo carmine staining](https://upload.wikimedia.org/wikipedia/commons/d/d9/Indigo_carmine_staining.jpg)
*
Endoscope
An endoscope is an inspection instrument composed of image sensor, optical lens, light source and mechanical device, which is used to look deep into the body by way of openings such as the mouth or anus. A typical endoscope applies several modern t ...
** Non-coaxial
optic fiber
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means ...
system to carry light to the tip of the endoscope
** A chip camera at the tip of the endoscope – this has now replaced the coaxial optic fibers of older scopes that were prone to damage and consequent loss of picture quality
** Air/water channel to clean the lens using the water and air channel for drying the lens itself and to insufflate the esophagus and the stomach during the operation to prevent from collapsing the track to better vision in the procedure
** Suction/Working channels – these may be in the form of one or more channels
** Control handle – this houses the controls
** Umbilical Cords that connect to the light source and video processor to supply the endoscope with suction and air pressure and water for (suction and irrigation process) and light to transmit in the body to deliver the video signal to the processor to show the live image on the monitor
* Stack
** Light source
** Suction
**
Electrosurgical unit
** Video recorder/photo printer
* Instruments
** Biopsy forceps
** Snares
** Injecting needles
* Chemical agents
**
Dimethicone
Polydimethylsiloxane (PDMS), also known as dimethylpolysiloxane or dimethicone, belongs to a group of polymeric organosilicon compounds that are commonly referred to as silicones. PDMS is the most widely used silicon-based organic polymer, as i ...
**
Acetate
An acetate is a salt (chemistry), salt formed by the combination of acetic acid with a base (e.g. Alkali metal, alkaline, Alkaline earth metal, earthy, Transition metal, metallic, nonmetallic or radical Radical (chemistry), base). "Acetate" als ...
**
Indigo carmine
Indigo carmine, or 5,5′-indigodisulfonic acid sodium salt, is an organic salt derived from indigo by aromatic sulfonation, which renders the compound soluble in water. It is approved for use as a food colorant in the U.S and E.U. to produce a ...
Image:Duodenal adenocarcinoma.png, Endoscopic image of adenocarcinoma of duodenum seen in the post-bulbar duodenum.
Image:Gastric_antral_vascular_ectasia_(before_and_after).png, Endoscopic image of gastric antral vascular ectasia
Gastric antral vascular ectasia (GAVE) is an uncommon cause of chronic gastrointestinal bleeding or iron deficiency anemia. The condition is associated with dilated small blood vessels in the pyloric antrum, which is a distal part of the stomach. T ...
seen as a radial pattern around the pylorus
The pylorus ( or ), or pyloric part, connects the stomach to the duodenum. The pylorus is considered as having two parts, the ''pyloric antrum'' (opening to the body of the stomach) and the ''pyloric canal'' (opening to the duodenum). The ''pylori ...
before (top) and after (bottom) treatment with argon plasma coagulation
Argon plasma coagulation (APC) is a medical endoscopic procedure used to control bleeding from certain lesions in the gastrointestinal tract. It is administered during esophagogastroduodenoscopy or colonoscopy.
Medical use
APC involves the use ...
Image:Barretts esophagus.jpg, Endoscopic image of Barrett's esophagus
Barrett's esophagus is a condition in which there is an abnormal (metaplastic) change in the mucosal cells lining the lower portion of the esophagus, from stratified squamous epithelium to simple columnar epithelium with interspersed goblet cells ...
, which is the area of red mucosa projecting like a tongue.
Image:Deep gastric ulcer.png , Deep gastric ulcer
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines i ...
Image:celiac 3.jpg, Endoscopic still of duodenum
The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine m ...
of patient with celiac disease
Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barl ...
showing scalloping of folds.
Image:MALT 4.jpg, Gastric ulcer
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines i ...
in antrum ''This is a disambiguation page for the biological term. For the 2018 horror movie, see Antrum (film)''
In biology, antrum is a general term for a cavity or chamber, which may have specific meaning in reference to certain organs or sites in the bod ...
of stomach
The stomach is a muscular, hollow organ in the gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach i ...
with overlying clot due to gastric lymphoma
Primary gastric lymphoma (lymphoma that originates in the stomach itself) is an uncommon condition, accounting for less than 15% of gastric malignancies and about 2% of all lymphomas. However, the stomach is a very common extranodal site for lymp ...
.
Image:DU 2.jpg , Endoscopic image of a posterior wall duodenal ulcer
Peptic ulcer disease (PUD) is a break in the inner lining of the stomach, the first part of the small intestine, or sometimes the lower esophagus. An ulcer in the stomach is called a gastric ulcer, while one in the first part of the intestines ...
with a clean base, which is a common cause of upper GI hemorrhage.
Early stomach cancer 2a.jpg, Endoscopic images of an early stage stomach cancer. 0-IIa, tub1. Left column: Normal light. Right column: computed image enhanced ( FICE). First row: Normal. Second row: Acetate
An acetate is a salt (chemistry), salt formed by the combination of acetic acid with a base (e.g. Alkali metal, alkaline, Alkaline earth metal, earthy, Transition metal, metallic, nonmetallic or radical Radical (chemistry), base). "Acetate" als ...
stained. Third row: Acetate-indigocarmine mixture ( AIM) stained.
See also
*
Colonoscopy
Colonoscopy () or coloscopy () is the endoscopic examination of the large bowel and the distal part of the small bowel with a CCD camera or a fiber optic camera on a flexible tube passed through the anus. It can provide a visual diagnosis (''e. ...
*
Transnasal esophagoscopy
References
{{Authority control
Endoscopy
Diagnostic gastroenterology