Evaluation of transabdominal ultrasound after oral administration of an echoic cellulose-based gastric ultrasound contrast agent for demonstrating small gastric subepithelial masses.

PURPOSE: To assess the role of transabdominal ultrasound after oral administration of an echoic cellulose-based gastric contrast agent (TUS-OCCA) for detection and characterization of small gastric subepithelial masses (≤3 cm) by comparison with endosonography (EUS).

METHODS: Ninety-five patients with small gastric subepithelial masses detected by gastroscopy examination were enrolled. For each patient, TUS-OCCA was performed prior to EUS by a skilled examiner. TUS-OCCA diagnoses were compared with those of EUS.

RESULTS: TUS-OCCA had a detection rate of 94% (89 of 95) in visualizing small gastric subepithelial masses previously detected by gastroscopy. The sizes of 6 undetected masses ranged from 7 to 12 mm (4 located at the fundus, 2 at the cardia). All of six patients whose lesions were undetected by TUS-OCCA were obese. The findings of gastric subepithelial masses demonstrated by TUS-OCCA were similar to that shown on EUS.

CONCLUSIONS: TUS-OCCA can provide useful information about small gastric subepithelial masses, especially for the patients who are not obese. It can be used to follow gastric submucosal tumors that are not excised.