
Duodenum
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

Mucosa
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

- Intestinal glands
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

Submucosa
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

- Brunner's glands
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

- Duct of Brunner’s gland
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x

Villi
This image of a plica circularis shows evaginations (villi) and invaginations (intestinal glands) of the mucosal epithelium. Ducts of Brunner’s glands join the bases of the intestinal glands. The presence of Brunner’s glands in the submucosa is a diagnostic feature of the duodenum 40x