Upper gastrointestinal tract and abdomen: water as an orally administered contrast agent for helical CT.
OBJECTIVE
To evaluate the use of orally administered water as a negative contrast agent and intravenously administered glucagon in helical computed tomography (CT) of the upper abdomen.


METHODS
Ninety-eight adult patients underwent 102 helical CT examinations. Patients received 700 mL of water orally 30 minutes before and another 350 mL of water orally with 1 mg of glucagon intravenously just before CT. The amount of water actually ingested was recorded. Luminal distention at five sites was graded on a three-point scale; depiction of six normal anatomic structures was evaluated.


RESULTS
Luminal distention improved with the amount of water ingested in four of the five sites (P < .03 in three sites). Depiction of all six normal anatomic structures improved with increasing luminal distention (P < .001). The normal duodenal papilla was seen in 42% (83 of 198) of the examinations. Of 87 patients who had previously undergone CT with positive oral contrast agents, 89% (n = 77) preferred the water, 11% (n = 10) had no preference, and none preferred the positive agent (P < .001). Upper gastrointestinal tract abnormalities were easily recognized and depicted.


CONCLUSIONS
Water is an efficacious negative contrast agent for evaluation of the upper gastrointestinal tract during helical CT.
Winter
T C
TC
Department of Radiology, University of Washington Medical Center, Seattle 98195, USA.
Ager
J D
JD
Nghiem
H V
HV
Hill
R S
RS
Harrison
S D
SD
Freeny
P C
PC
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage*; D004064:Digestive System / Q000000981:diagnostic imaging* / Q000187:drug effects; D005260:Female; D005934:Glucagon / Q000008:administration & dosage / Q000494:pharmacology; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D011860:Radiography, Abdominal; D014057:Tomography, X-Ray Computed; D014867:Water / Q000008:administration & dosage
D003287:Contrast Media; D014867:Water; D005934:Glucagon