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.
Department of Radiology, University of Washington Medical Center, Seattle 98195, USA.
T C
TC
Winter
J D
JD
Ager
H V
HV
Nghiem
R S
RS
Hill
S D
SD
Harrison
P C
PC
Freeny
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