Comprehensive evaluation of various parameters for assessment of delayed gastric emptying of solids

Abstract

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Objectives: To determine the best parameter(s) for assessment of delayed gastric empting (GE) of solids among various parameters obtained from a comprehensive 4-hour (h) solid GE study.

Methods: All consecutive 4-h solid GE studies for suspected delayed GE performed from 10/03-10/05 were analyzed with respect to various parameters previously utilized/proposed for assessment of GE, including GE T½ obtained from imaging timepoints between 0 and 90 (T½ 0-90), 0 and 120 (T½ 0-120), 0 and 240(T½ 0-240), and 120 and 240(T½ 120-240) minutes (min); % remaining gastric activity at 120 (%RGA120) and 240 (%RGA240) min. All patients (pts) ingested a standard egg-based meal containing 1 mCi of 99mTc-sulfur colloid with subsequent serial imaging for 4 h (in 10-min intervals up to 120 min and then at 240 min). GE time-activity curves were generated from geometric means of anterior and posterior gastric counts. Receiver-Operating-Characteristics (ROC) was performed to determine the diagnostic accuracy and optimum cutoff for each parameter (i.e., point on the ROC curve with the minimum distance between the 0% false-positive rate and 100% true-positive rate). Final diagnosis of delayed GE was obtained based on clinical, endoscopic and laboratory assessment (e.g., uncontrolled hyperglycemia in pts with diabetes, hypothyroidism, pts with documented pyloric dysfunction or scleroderma).

Results: Of the 64 pts studied, 29 were found to have delayed GE based on clinical, endoscopic and laboratory assessment, while the remaining 35 did not have evidence of delayed GE with their symptoms explained by other disorders such as bacterial overgrowth, fructose/lactose intolerance, etc. The table below lists the various GE parameters investigated, the area under the ROC curve and the optimum cutoff point for these parameters with associated sensitivity and specificity. The table shows that the GE T½ obtained from imaging timepoints ranging from 0 to 240 min as well as %RGA at 120 or 240 min result in moderate sensitivity and/or specificity for diagnosing delayed GE of solids with no significant differences found between these various parameters.

Conclusions: Among all parameters investigated, %RGA at 120 min provides a relatively fair balance between sensitivity and specificity, is easily obtained and can, therefore, be used as the preferred single parameter for assessment of delayed GE of solids.