UPHS Radiology -- Radiology Handbook

Radiology Handbook

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Gastrointestinal System

Gastrointestinal System Quick Links Abdomen Survey Abdomen-Erect Radiograph Decubitus Radiographs X-Ray Exam of the Colon The Esophagus, Stomach & Duodenum Small Bowel Peroral Pneumocolon Fistulagram Tube Placement

ABDOMEN SURVEY

Description:

A supine AP radiograph of the abdomen is made.

Indications:

Abdominal pain.
Suspected calculus in any viscus.
Suspected obstruction or a dynamic ileus (see erect radiograph – obstruction series).
Palpable abdominal mass.
Suspected perforation of the viscus (see erect film – obstruction series)
Abdominal trauma.
Suspected organomegaly.
Abdominal distention.

Low Yield Indications:

Chronic abdominal pain.
Gastrointestinal hemorrhage.

ABDOMEN-ERECT RADIOGRAPH

Description:

A standing radiograph is made in the PA or AP position with the diaphragm included in the upper portion of the film. This film is made in combination with the supine film and together the two may be designated "obstruction series".

Indications:

Suspected perforation of a hollow viscus.
Suspected obstruction or a dynamic ileus.

DECUBITUS RADIOGRAPHS

Description:

An AP or PA radiograph is made with the patient lying on his or her right or left side.

Indications:

Used instead of the erect radiograph if the patient is unable to stand.
Sometimes useful in conjunction with the supine and erect films in suspected obstruction

Contraindications:

Suspected cephalopelvic disproportion. This technique has largely been supplanted by non-radiologic techniques.

X-RAY EXAMINATION OF THE COLON (BARIUM ENEMA, DOUBLE CONTRAST ENEMA)

Description:

If an x-ray examination of the colon is ordered, a double contrast enema will be performed routinely if it is technically possible. A single contrast enema will be performed in the patient suspected of having obstruction, fistula, or unusually complex anatomy.

Single Contrast Enema: The colon is filled with barium under fluoroscopic control. Spot films and overhead radiographs are taken of the entire colon.

Double Contrast Enema: A higher density barium suspension is used to coat the mucosal surface of the colon. Air is insufflated to distend the colon and render it translucent. Spot radiographs and overhead images are taken of the entire colon. 1mg of glucagon may be administered intravenously if there is either spasm of the colon, excessive patient discomfort or inability to retain the contrast.

Indications:

To rule out intrinsic disease of the colon, rectum, and terminal ileum.
To demonstrate colonic involvement by extra colonic masses or inflammatory processes.

Contraindications:

Known or suspected colonic perforations. In such cases, a contrast study using a water-soluble contrast agent such as Gastroview can be performed.
Toxic megacolon and patients with any type of severe colitis. In general, when contrast studies are required in such patients, one of the staff radiologists should be consulted and alerted.
Recent colonic biopsy. Following mucosal biopsy through the rigid proctosigmoidoscope, elective x-ray examination of the colon should be postponed for one week because of the risk of rectal perforation. If a protruding mass was biopsied, no delay is necessary. If the biopsy is taken with the smaller biopsy forceps used with the flexible fiberoptic endoscope, no delay is necessary provided that the endoscopy was not unduly traumatic. If a snare polypectomy or a hot biopsy was performed, the examination should be delayed one week.

Preparations:

Day before examination:

Clear liquids only the day before the exam.
5:00 PM - 10 oz. of magnesium citrate.
8 oz. of water every 4 hours throughout the evening.
10:00 PM - 4 tablets of Dulcolax with one full glass of water.

Day of examination:

In the early morning, a Dulcolax suppository.
Nothing by mouth after midnight until after the examination.

Complications:

The examination may be unsuccessful if the patient is unable to retain contrast either because of colonic spasm or poor anal sphincter tone.
Distention of the colon may produce fainting or syncope in some patients. Other patients may complain of cramps due to the insufflation of air.
Although rare (less than 1 in 40,000), the major complication is perforation of the colon. The usual site will be a rectal tear caused by aggressive attempts to complete the barium enema in patients unable to retain contrast. Perforation of the proximal colon is usually related to severe colitis or ischemia.
Some patients may experience difficulty evacuating the barium. After the examination, patients should be encouraged to drink large quantities of fluid and a laxative may be administered.

THE ESOPHAGUS, STOMACH AND DUODENUM (UPPER GI SERIES, DOUBLE CONTRAST UPPER GI, ESOPHAGRAM)

Description:

When an upper gastrointestinal series is requested, a double contrast study will be performed routinely. A single contrast examination is performed when the patient is unable to cooperate for the double contrast study or when an obstruction, leak, or a fistula is suspected.

The routine examination includes the thoracic esophagus. If a detailed examination of the pharynx and esophagus is required, a videopharyngo-esophagram should be requested. If the disorder involves the pharynx or cervical esophagus, a videotape or DVD examination will be included. Videotape or DVD will also be used to record esophageal motility.

Single Contrast:
Barium is ingested and multiple spot films are exposed with the use of compression to optimize mucosal details. Overhead radiographs may also be taken. If a postoperative study is being performed, a water-soluble contract agent (gastroview) will be used initially. If no perforation is seen, barium will then be administered.

Double Contrast:
An effervescent agent is swallowed to release carbon dioxide in the stomach. A high-density barium suspension is then ingested and the patient is rotated to coat the mucosal surface of the distended stomach. Multiple spot films of the esophagus, stomach, and duodenum are obtained.

0.1mg glucagon is usually administered intravenously at the beginning of the examination to induce gastrointestinal hypotonia. Occasionally, for detailed examination of the esophagus, a small tube may be passed into the esophagus for more controlled double contrast examination (tube esophagram).

Indications:

To rule out intrinsic disease of the esophagus, stomach and duodenum.

To evaluate secondary gastric involvement by disease in adjacent organs.

Contraindications:

A known or suspected perforation. Water-soluble contrast such as gastroview should be used. Note: if aspiration or a tracheoesophageal fistula are suspected, gastroview should not be used since it incites a chemical pneumonitis. If there is moderate ro marked danger of the contrast entering the tracheobronchial tree, barium should be used.

Inability of the patient to swallow. In this instance examination of the stomach and duodenum may be accomplished if a naso-gastric tube is in place.

Preparation:

Nothing by mouth after 9 P.M. the day before the examination

Complications:

Oral barium should not be administered to patients with known perforation of the gastrointestinal tract. Although it is somewhat controversial, it is probably prudent not to administer oral barium to patients with obstruction of the left colon because of the possible risk of barium inspissation. If the patient is scheduled for additional radiologic studies, hydration is encouraged and laxatives may be administered.

SMALL BOWEL (SMALL BOWEL FOLLOW-THROUGH, SMALL BOWEL ENEMA)

Description:

Small bowel follow-through:
This examination is usually performed following a single contrast examination of the upper gastrointestinal tract. An additional 12-16 ounces of barium is administered and periodic radiographs of the small bowel are obtained and intermittent fluoroscopy is performed. The examination may last anywhere from one to four hours depending on the transit time through the small bowel.

In some patients a small bowel follow-through may be performed without the upper GI examination if the clinical signs and symptoms point specifically to an abnormality in the small bowel.

Small bowel enema:
This is a more detailed examination of the small bowel performed in patients with a high index of suspicion for disease in the small bowel or with previous suspicious or inconclusive radiologic studies. A tube is passed into the proximal small bowel or the examination can be performed through an indwelling intestinal tube. Under fluoroscopic control, barium is injected through the tube followed by methylcellulose to propel the barium forward and to distend the small bowel. Multiple spot films are obtained with compression. The examination usually lasts 20-60 minutes.

Indications:

To rule out diseases of the small bowel.

Contraindications:

Known or suspected perforation of the gastrointestinal tract.

Preparation:

Small bowel follow-through: Nothing by mouth after midnight.

Small bowel enema:

Clear liquids only the day before the exam.

Four Dulcolax tablets 4-5 PM day before exam.

Nothing by mouth after midnight until after examination.

Complications:

Rare. Vomiting and aspiration may occur if there is excessive reflux of methylcellulose into the stomach.

PERORAL PNEUMOCOLON

Description:

Barium is administered by mouth. A small bowel follow-through is performed. When barium column reaches the mid-transverse colon, the peroral pneumocolon is then performed. A small rectal catheter is then introduced and air is insufflated to distend the right colon and terminal ileum. 1mg glucagon is administered intravenously to relax the colon and to promote reflux of air into the terminal ileum. Spot and overhead radiographs are obtained.

Indications

Detailed examination of the ileocecal region, terminal ileum or right colon. This examination can be used in patients in whom a barium enema has been unsuccessful in demonstrating the right colon or terminal ileum and in patients requiring detailed evaluation of the terminal ileum and ileocecal area.

Contraindications:

Ischemic colitis, toxic megacolon, or severe colitis.
Perforation of the gastrointestinal tract.

Preparation:

If the examination is being planned because of a previously suspected lesion, the preparation is the same as that for the small bowel enema:

Clear liquids only by mouth for 24 hours.
Four Ducolax Tablets 4-5 P.M., day before exam.
Nothing by mouth after 10 PM until after examination.

FISTULAGRAM

Description:

A small soft rubber catheter is placed into the fistulous tract. Water-soluble contrast material is injected and fluoroscopic and overhead radiographs are obtained. It is helpful if the clinician identifies the hole on the skin’s surface that is to be injected.

Indications:

To demonstrate the internal origins and connections of a cutaneous fistula. A fistulagram should be ordered before a barium examination is ordered to evaluate for communication of the GI tract and the fistula tract opening.

Contraindications:

Allergy to iodinated contrast material. (Barium can be used if there is an allergy to iodinated contrast material.)

Complications:

Septicemia is a possible complication.

TUBE PLACEMENT (MILLER-ABBOTT TUBE, FEEDING TUBE)

Description:

Under fluoroscopic control, the tube is manipulated in an attempt to advance it into the duodenum. If fluoroscopic manipulation is unsuccessful, the patient should be maintained on his/her right side to facilitate spontaneous passage.

Indications:

To assist in the passage of these tubes through the pylorus into the duodenum.

Preparation:

These tubes should initially be passed on the floor. The patient should be instructed to lie on the right side to promote the passage of these tubes spontaneously into the duodenum. Abdominal radiographs may be obtained after a few hours to determine the location of the tube. If the tube has not passed into the duodenum after 24 hours fluoroscopic assistance may be requested. Use of Metoclopramide is helpful for either feeding tube or long intestinal tube passage through the pylorus.