CT of gastric masses: Image patterns and a note on potential pitfalls

Abstract

Computed tomography (CT) was performed in 9 consecutive cases of primary gastric neoplasm. Lesions were surgically or endoscopically proved; cross-sectional images are correlated to specific histopathology in each case. The CT images of leiomyoma and leiomyoblastoma are characterized as models of pure bulging intramural growth resulting in a lunate contrast distribution when imaged in the cross-sectional plane. In 5 cases of lymphoma, distortion of the contrast-filled hollow viscus is relatively consistent. Nodular growth is reflected on the CT image as a series of digitations encroaching on the opacified portion of the gastric lumen. Image pattern recognition, relative to histopathology, is of more than academic interest since endoscopy is frequently unreliable in cases of submucosal and exophytic pathology. Further, biopsy of such lesions is commonly nondiagnostic as a result of random choice of biopsy site or inadequate depth of tissue sample. Additionally, this report includes images of lesions that simulate the primary gastric pathology and may be a source of erroneous interpretation. These include: pseudocyst of the pancreas (2 cases) and enlargement of the left lobe of the liver with encroachment on the gastric lumen (1 case). Image specificity on CT examination is increasingly essential to diagnosis and surgical planning.

Use of water or air as oral contrast media for computed tomographic study of the gastric wall: Comparison of the two techniques

“…The water technique showed more gastric wall details and the lesion's limits could be defined more accurately. The acceptance and tolerance of the gas-producing agent was better in severely ill patients than tap water.Upper gastrointestinal double-contrast barium studies [1, 2] and endoscopy [3] usually provide good diagnostic information about most gastric mucosa alterations.However, these methods cannot precisely determine the submucosal, intramural, or exophytic extension of a given gastric lesion.Computed tomography (CT) has been suggested as a complementary technique in the study of gastric wall lesions, since it allows direct visualizations of Address offprint requests to: Konstantinos J. Gossios, M.D., 9 Dosiou Str., Ioannina 453 33, Greece the gastric wall thickness and the neighboring tissues.Full gastric distention is necessary to appreciate the exact thickness of the gastric wall [4].It is believed that gastric wall thickening found on CT study is an important indicator of gastric tumor [5][6][7] or inflammatory process of the gastric wall [4].To achieve optimal distention of the gastric lumen, various techniques have been used. These include the ingestion of diluted iodinated contrast or barium solutions, the use of oil emulsion or gas distention by effervescent granules, and recently the use of water as oral contrast medium [8][9][10][11][12].…”

“…It is believed that gastric wall thickening found on CT study is an important indicator of gastric tumor [5][6][7] or inflammatory process of the gastric wall [4].…”

Intramural gastric pseudocyst

“…A suspicious finding of a “lesion” on upper endoscopy or on cross-sectional imaging may be more or less obvious; [ 14 ] however, the recognition and interpretation of this finding as an intramural gastric or duodenal pseudocyst may be a challenge. [ 6 , 15 , 16 ] This rare condition, although first described approximately 50 years ago, [ 2 ] does not seem to be easily recognized or interpreted correctly, which may cause diagnostic delay or inappropriate management.…”