Lichen Sclerosus et Atrophicus: A chronic inflammatory mucocutaneous disease usually affecting the female genitalia (VULVAR LICHEN SCLEROSUS) and BALANITIS XEROTICA OBLITERANS in males. It is also called white spot disease and Csillag's disease.Phimosis: A condition in which the FORESKIN cannot be retracted to reveal the GLANS PENIS. It is due to tightness or narrowing of the foreskin opening.Scleroderma, Localized: A term used to describe a variety of localized asymmetrical SKIN thickening that is similar to those of SYSTEMIC SCLERODERMA but without the disease features in the multiple internal organs and BLOOD VESSELS. Lesions may be characterized as patches or plaques (morphea), bands (linear), or nodules.Vulvar Lichen Sclerosus: Atrophy and shriveling of the SKIN of the VULVA that is characterized by the whitish LICHEN SCLEROSUS appearance, inflammation, and PRURITUS.Hyalin: A clear, homogenous, structureless, eosinophilic substance occurring in pathological degeneration of tissues.Histological Techniques: Methods of preparing tissue for examination and study of the origin, structure, function, or pathology.Vulvar Diseases: Pathological processes of the VULVA.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Lichens: Any of a group of plants formed by a symbiotic combination of a fungus with an algae or CYANOBACTERIA, and sometimes both. The fungal component makes up the bulk of the lichen and forms the basis for its name.Lichen Planus: An inflammatory, pruritic disease of the skin and mucous membranes, which can be either generalized or localized. It is characterized by distinctive purplish, flat-topped papules having a predilection for the trunk and flexor surfaces. The lesions may be discrete or coalesce to form plaques. Histologically, there is a "saw-tooth" pattern of epidermal hyperplasia and vacuolar alteration of the basal layer of the epidermis along with an intense upper dermal inflammatory infiltrate composed predominantly of T-cells. Etiology is unknown.Vulvar Neoplasms: Tumors or cancer of the VULVA.Clobetasol: A derivative of PREDNISOLONE with high glucocorticoid activity and low mineralocorticoid activity. Absorbed through the skin faster than FLUOCINONIDE, it is used topically in treatment of PSORIASIS but may cause marked adrenocortical suppression.Vulva: The external genitalia of the female. It includes the CLITORIS, the labia, the vestibule, and its glands.