B

barium enema A diagnostic imaging procedure
to examine the structures of the lower gastroin-
testinal tract including the RECTUM and COLON,
sometimes called a lower GI (gastrointestinal)
series. The gastroenterologist may request a bar-
ium ENEMA to help diagnose intestinal polyps,
DIVERTICULAR DISEASE, INFLAMMATORY BOWEL DISEASE
(IBS), HIRSCHSPRUNG’S DISEASE, intestinal obstruc-
tion, COLORECTAL CANCER, and RECTAL PROLAPSE.
Preparation for barium enema typically includes a
clear liquid diet for two days before the procedure,
a laxative the night before the procedure, and an
ENEMA the morning before the procedure to
cleanse the colon.
The test consists of a barium mixture adminis-
tered via enema, followed by a series of X-rays
(FLUOROSCOPY). Body position and the heaviness of
the barium help the barium mixture to flow
upward into the lower gastrointestinal tract. For a
single-contrast barium enema, the radiologist
takes X-ray images of the barium-filled colon and
rectum. For a double-contrast barium enema the
person eliminates as much barium as possible after
the first series of X-rays, then the radiologist
injects a small amount of air into the lower bowel
and takes another X-ray series. Double-contrast
barium enema provides more detailed visualiza-
tion. The heaviness and pressure of the barium
make the procedure uncomfortable and some peo-
ple experience cramping. The procedure takes 20
to 45 minutes, with the person placed in different
positions to help move the barium through the
colon. Light-colored stools are normal for several
days after the procedure while the barium clears
the body. A rare complication is bowel perfora-
tion.
See also BARIUM SWALLOW; COLONOSCOPY; INTES-
TINAL POLYP; LAXATIVES.

barium swallow A diagnostic imaging procedure

to examine the structures of the upper gastroin-

testinal tract including the ESOPHAGUS, STOMACH,

and DUODENUM(beginning of the SMALL INTESTINE),

sometimes called an upper GI (gastrointestinal)

series. The gastroenterologist may request a bar-

ium swallow to help diagnose HIATAL HERNIA,

esophageal obstruction, ESOPHAGEAL SPASM, stom-

ach dysfunction, and PEPTIC ULCER DISEASE. Prepara-

tion for barium swallow typically is nothing to eat

or drink for 8 to 12 hours, before the procedure.

The test consists of swallowing a preparation of

barium, a high-contrast medium, during a series of

X-rays (FLUOROSCOPY). The barium lines the struc-

tures of the upper gastrointestinal tract, making

them visible by X-ray. The barium preparation is

about the consistency of a milkshake though chalky

in texture. The procedure takes 30 to 60 minutes,

with the person placed in different positions to help

move the barium through the upper gastrointestinal

tract. Some people experience mild CONSTIPATION

after the procedure, and it is normal for the stools to

be light-colored for several days after the procedure

while the barium clears the body.

See also BARIUM ENEMA; ENDOSCOPY.

Barrett’s esophagus Changes to the lining of the

ESOPHAGUSin which the tissue becomes similar to

that of the intestine. The altered tissue is Barrett’s

esophagus does not itself cause symptoms, though

the condition often appears in association with

GASTROESOPHAGEAL REFLUX DISORDER(GERD), which

does cause symptoms. The key clinical significance

of Barrett’s esophagus is its association with a rare

and deadly form of CANCER, esophageal ADENOCAR-

CINOMA. Though few people who have Barrett’s

esophagus will develop esophageal adenocarci-

noma, nearly everyone who does develop

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