The double-contrast upper gastointestinal (UGI) examination is an effective means of clearly demonstratingcomplete gastric erosions. The main radiographic feature of the complete gastric erosion is a small barium flecksurrounded by a radiolucent halo in the gastric mucosa. From Jan. 1984 to Dec. 1986 a total of 48 cases ofcomplete gastric erosions was diagnosed by doublecontrast UGI examinations, and then 12 cases among them underwentendoscopy within 6 days of UGI examination. For evaluation of the relationships of the diameters of radiolucenthalos to the central barium flecks, the radiographic findings were reviewed. 1. 1) The male to female ratio was 20:28. The age of patients ranged from 15 to 76 years, and the most common age group was 6th decade. 2) Theclinical symptoms included epigastralgia(63%), indigestion, hunger pain, and vomiting. 2. Thirteen coexistentdiseases were found in 11 patients (22.9%): gastric ulcer in 4 patients, doudenal ulcer in 3, gastric cancer in 3,liver cirrhosis in 2, and hepatoma in one. 3. The gastric antrum was involved in all cases. The gastric body wasalso involved in 8 case, and duodenal bulb in 2 cases. 4. In all cases there were multiple complete erosions. Thenumber of the esosions were 2 to 10 in 83.4% of cases. The radiographic findings of 330 complete erosions in the48cases were analyzed: 1) The diameters of surrounding halos varied frm 3 to 11mm, and the sized of the centralbarium flecks from 0(No central barium fleck) to 5mm. The shapes of central barium flecks were round in 70.6% ofcomplete erosions. 2) In general, the small central barium flecks had small surrounding halos, and the large oneslarge halos(correlation coefficient r=0.97). But with the enlargement of central barium flecks, the ratios of thediameters of surrounding halos to the size of central barium flecks tended to decrease by degrees. It appears thatin the formation of a surrounding mucosal elevation (radiolucent halo) of a complete erosion, the existence of amucosal defects is more important than the size of a mucosal defect.