Members of the DEWS Definition and Classification. Subcommittee developed a contemporary definition of dry eye disease and a three-. part classification system based on etiology, causative mechanisms and disease. severity.
Metaplasia. Definition: Metaplasia is the reversible replacement of one differentiated cell type with another differentiated cell type. Metaplasia causes precursor cells to change their cell fate, and do not change existing differentiated cells.he most common epithelial metaplasia is columnar to squamous (squamous metaplasia), as occurs in the respiratory tract in response to chronic irritation.
Click to enlarge image. Tubal metaplasia is a common phenomenon in the endocervical glands where endocervical cells become cuboidal and may show cilia. Tubal metaplasia also shows some crowing of the nuclei and hyperchromasia and therefore it can be misinterpreted as endocervical dysplasia or adenocarcinoma in situ.