A Case of Gastric Hyperplastic Polyp Exhibiting the Scarf-Ring Sign After Successful <i>Helicobacter pylori</i> Eradication

Gastric hyperplastic polyps are associated with atrophic gastritis caused by Helicobacter pylori (H. pylori) infection and possess a low but notable malignant potential. In the absence of malignant transformation, H. pylori eradication therapy is typically performed, often resulting in regression or disappearance of the polyps. However, in some cases, polyps may enlarge or undergo morphological changes despite successful eradication. The "scarf-ring sign" is a rare endoscopic finding in which a gastric polyp prolapses into the duodenum, with its stalk passing through the pyloric ring. When accompanied by symptoms such as abdominal pain, nausea, or vomiting due to obstruction, it is diagnosed as ball valve syndrome.