ORAL CONTRAST MEDIA COMPOSITION FOR COMPUTERIZED AXIAL TOMOGRAPHIC EXAMINATIONS AND METHOD
BACKGROUND OF THE INVENTION
This invention relates to gastrointestinal contrast agents and more particularly to a
composition providing gastrointestinal contract for computerized axial tomographic
examinations of acute abdomen in a clinical setting in instances where a poorly compliant
patient is limited by the amount of oral intake.
The clinical condition of acute abdomen often results in bowel distention and fluid-
filled bowel loops which respond poorly to oral contrast media that contain salts of diatrizoic
acid. There are commercially available salts of diatrizoic acid such as Gastrografin sold by
Bracco Diagnostics, Inc. of Milan, Italy, and Gastroview sold by Mallinckrodt, Inc. of St.
Louis, MO. Both products contain identical amounts of pharmacologically acceptable non¬
toxic salts of diatrizoic acid comprising approximately 660 milligrams of meglumine
diatrizoate and 100 milligrams of sodium diatrizoate solutions. The recommended dosage
of these salts for computerized tomographic examinations is 25 milliliters (containing 9.17
grams of iodine) in 1000 milliliters of water, which is administered orally approximately 15
to 30 minutes prior to imaging. Unfortunately, individual dosing can be difficult to
administer because of lack of a measuring tool. Furthermore, bowel opacification is often
scant, dilute or unopacified due to a dilutional effect which occurs which this large volume
of fluid mixed with the enteric fluid contained within distended bowels . As result, diarrhea
is a common side effect due to the overload of a large amount of fluid volume in the
gastrointestinal tract. Although in cases where the acute abdomen is complicated by a bowel
perforation, diatrizoate salt solutions can permeate freely into the peritoneal cavity without
adverse effects, unlike barium suspension, but it is colorless and therefore undetectable.
Barium suspension induces peritonitis when free in the peritoneal cavity and is therefore
contraindicated in the setting of an acute abdomen. Another problem can result from the
fact that diatrizoate salts are also bitter and unpleasant tasting, thereby further contributing
to reduced patient compliance.
Thus, a need exists for an oral composition of diatrizoate salts which provide a
sufficient and faster rate of gastrointestinal contrast for computerized axial tomographic
examinations in the clinical setting of acute abdomen, especially where bowel perforation
is expected, which overcomes the above problems. The prior art contains contrast agents
but none like the present invention, as follows:
Patent Number Inventor Issue Date 5,233,005 Yudelson et al. 8-10-1993
4,735,795 Robinson et al. 4-5-1988
5,360,604 Ruddy et al. 11-1-1994
6,414,857 Henrichs et al. 7-23-2002
6,375,931 Ostensen et al. 4-23-2002 6,409,671Bl Eriksen et α/. 6-25-2002
5.716,642 Bagchi et α/. 2-10-1998
4,474,747 Oimo et al 10-2-1984
SUMMARY OF THE INVENTION
The primary object of the subject invention is to provide a composition which reduces the
amount of oral intake required for sufficient gastrointestinal contrast.
Another object of the present invention is to provide a composition which reduces the
incidence of diarrhea.
A further object of the present invention is to provide such a composition which can be
provided in individual dosing thereby eliminating the need for measuring.
An even further object of the present invention is to provide a composition which is
packaged for efficient, economical storage in bulk quantities.
An additional object of the present invention is to provide such a composition which is colored to aid in the identification of bowel perforation in an operative setting.
The present invention fulfills the above and other objects by providing an oral crystalline
composition having a pharmacologically acceptable non-toxic salt of diatrizoic acid in a low-
calorie, non-sweetened drink mix. The non-toxic salt of diatrizoic acid may be meglumine
diatrizoate or sodium diatrizoate, the non-sweetened drink mix would preferably be the drink mix
sold by Kraft General Foods under the trademark Crystal Light. Preferably the composition
would contain 13.2 grams of meglumine diatrizoate, or 2.0 grams of sodium diatrizoate. The
composition would be orally administered at a pre-determined time period prior to conducting
the computerized axial tomographic examination, approximately 15 minutes in the case of the
abdomen, 30 minutes in the case of the pelvic area and 45 to 60 minutes where visualization of
the color or appendix is required.
The above and other objects, features and advantages of the present invention should
become even more readily apparent to those skilled in the art upon a reading of the following
detailed description of the preferred embodiments of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Salts of diatrizoic acid are used as radiographic contrast materials suitable for intravascular
injection and oral administration for visualization of internal body organs and structures.
Pharmacologically acceptable and non-toxic salts of diatrizoic acid are referenced in the US
Pharmacopeia and comprise meglumine diatrizoate and sodium diatrizoate. Meglumine diatrizoate
is designated chemically as l-deoxy-l-(methylamino )-D-glucitol 3,5-diacetamido-2,4,6-
triodobenzoate. Sodium diatrizoate is designated chemically as monosodium 3,5-
diacetamido-2,4,6-triiodobenzoate. The clinical pharmacology of diatrizoate salts for use as
gastrointestinal contrast media is the high atomic weight of iodine, which produces adequate
radiodensity for radiographic contrast of body tissues, and its poor absorption from the
gastrointestinal tract. Sodium diatrizoate contains more iodine on a weight basis, and is
therefore more effective as a radiographic contrast agent, but is limited in high doses by its
toxicity. Meglumine diatrizoate contains less iodine, but its solutions tend to be more viscous
and less toxic. Accordingly, combinations of meglumine diatrizoate and sodium diatrizoate
are used in combination.
In practicing the invention, the mixture of dry ingredients, comprised of 13.2 grams
of meglumine diatrizoate, 2.0 grams of sodium diatrizoate, and 1.8 grams of Crystal Light
low calorie non-sweetened drink mix (sold by Kraft General Foods, Inc., Rye Brook, New
York) provides sufficient bowel contrast opacification, when dissolved in only 8 ounces
(1 cup) of water, and prescribed as a prepared beverage. The beverage is orally administered
15 minutes prior to computerized axial tomographic imaging of the abdomen; 30 minutes for
the pelvic area, for opacification of small bowel loops; and 45 to 60 minutes in cases where
visualization of the colon or appendix is required. Improved patient compliance is
encountered because of the pleasant taste. A lower incidence of diarrhea is encountered
because of the relatively small amount of oral fluid intake, which also facilitates the
dispersion of diatrizoate salts in distended, fluid-filled bowel loops. The inclusion of colored
dyes contained in Crystal Light drink mix can aid in the visualization of free bowel
perforations and collections to the naked eye, as encountered during surgical or interventional
radiology procedures.
The composition further would preferably be divided into individual doses for easy
administration. An individual dose would comprise approximately 8 ounces, or one cup, and
would have 10 calories, 96 milligrams of sodium (4.2 milliequivalent), 7.3 grams of
organically bound iodine, 0 sugars, and 0 protein and bear a warning that it contains
phenylalanine.
The invention now having been fully described, it should be understood that it may be embodied in other specific forms or variations without departing from its spirit or essential characteristics. Accordingly, the embodiments described above are to be considered in all respects
as illustrative and not restrictive. The scope of the invention being indicated by the appended claims
rather than the foregoing description, and all changes which come within the meaning and range of
equivalency of the claims to be embraced therein.