[Adenoma of the pigmented epithelium of the iris with endothelialization and descemetization in the horse].

The research article details the observation, removal, and analysis of unusual tumors in the eye of a horse, which were identified as adenoma of the iris pigment epithelium. The white patches seen on the tumor surface were found to be a Descemet-like material, believed to be produced by displaced corneal endothelial cells.

Observation of the Tumor

• The authors first noted peculiar tumors in the eyes of an adult horse. These tumors displayed a brown and white piebald pattern on their anterior surface.
• They had grown from the corpora nigra (dark, irregular masses) in both eyes of the horse, causing occlusion or blockage of the pupils.

Surgical Procedure and Postoperative Treatment

• A larger tumor was surgically removed from one of the eyes, and the postoperative treatment process is delineated in the article.
• The authors presumably outline the technique used, as well as any pharmaceutical or therapeutic measures taken post-surgery to ensure the welfare of the horse and recovery of the eye.

Microscopic Analysis and Findings

• Both light and electron microscopy was used to evaluate the tumor. These state-of-the-art imaging techniques provided the researchers with a detailed view of the tumor at the cellular level.
• The researchers concluded that the tumors represented an adenoma of the iris pigment epithelium. Adenomas are benign tumors that originate in the epithelial tissue of a gland or gland-like structure.

Corneal Endothelial Cells and Descemet-like Material

• The white patches observed on the surface of the tumor were determined to consist of newly formed material similar in structure to Descemet’s membrane, a thin but strong film that serves as a protective barrier for the cornea and underlies the corneal endothelium.
• The researchers suggest that this material was produced by displaced corneal endothelial cells, which likely began proliferating on the tumor’s surface after coming into contact with the posterior face of the cornea.