GASTRIC EMPTYING

INDICATIONS:

Diagnosis of functional gastric obstruction/dysmotility.

PATIENT PREPARATION:

Overnight fast is desirable. NPO at least 3 hours prior to study is required.

The study should be done in the morning because the gastric emptying time varies with the time of day.

RADIOPHARMACEUTICAL:

For solid meal, 400 mCi Tc-99m albumin or sulfur colloid is mixed with cooked eggs.

For liquid meals, 400 mCi Tc-99m colloid or Tc-99m DTPA in water.

SCANNING TIME:

Variable, ranges from 1 hour to several hours.

Normal ranges: 50-90 minutes for solids.

Less than 20 minutes for liquids.

OTHER CONSIDERATIONS:

1. If both solid and liquid evaluation is desired, they should be ordered separately. 2. Inform Nuclear Medicine in advance if the patient is allergic to eggs so that an alternate food mixture can be prepared.

3. Reglan may cause more rapid gastric emptying. Initially, the patient should be evaluated off Reglan.

4. If patient is nauseated, the study should be delayed until antiemetics are effective.

RATIONALE:

1. Images and computer acquisition of data are required. A graphic representation of gastric emptying (time-activity histogram) and half-disappearance time is obtained from the slope.
2. The effect of Reglan can be evaluated by performing the study with the patient on and off medication.