Introduction:
Dry eye disease affects about 12 million people in the US.
In the human eye, the precorneal tear film covering ocular surfaces is composed of three primary layers: the mucin layer, the aqueous layer and the lipid layer. Each layer plays a role in the protection and lubricaiton of teh eye and thus affects dryness of the eye or lack thereof. Dryness of the eye is a recognized ocular diasese, which is referred to as “dry eye” or “dry eye syndrome” or “keratonjunctivitis sicca (KCS”). Korb (US 2013/0308095)
Dry eye can cause symptoms, such as itchiness, buring, and irritation, which can result in discomfort.
The integrity of the tear film lipid and aqueous layers is critical for proper tear film function and avoidance of dry eye.
Definitions:
Cornea: is a transparent front part of the eye that covers an iris, a pupil, and an anterior chamber that is disposed in front of the lens. Light passes through the transparent cornea and then through the pupil to fall upon a retina that senses the passed light. Together, the retina and a brain produce vision. There is a correlation between the ocular tear film layer thicknesses and dry eye disease. Korb (US 2013/0308095)
The function of the eye can be affected by aberrations to the shape of the cornea. Thus, clinical diagnosis of vision will benefit from capturing and displaying a corneal topography image. In essence, corneal topography is a non-invasive procedure used to determine the shape and integrity of the cornea of the eye. The clinician projects a series of illuminated rings onto the surface of the cornea. The pattern is reflected back into a computerized camera which analyzes the pattern to generate a topographical map of the cornea. The topographic images are analyzed to determibne the health of the eye. For example, cornea topography is used to analyze corneas before and after vision correction surgery and for contact lens fitting. It is known that a contact lens fitting that is too tight interfers with natural tear flow. Thus, it is important to provide a precorneal tear film analysis after a contact lens fitting. Grenon (US 2015/0138505)
Precorneal tear film: covers ocular surfaces and is composed of the following three primary layers:
(1) mucin layer is comprised of many mucines which retain aqueous matter in the middle layer of the tearm film known as the aqeuous layer. Thus the mucus layer is important in that it assists in the retention of aqueous matter on the cornea to provide a protective layer and lubrication.
(2) aqueous layer is the middel layer that comprises the builk of the tear film. The aqueous layer is formed by secretion of aqueous matter by lacrimal glands and accessory tear glands surrounding the ye. The acqueous matter secreted by the lacrimal glands and assessory tear glands is knwon as “tears”. The function of the aqueous layer is to help flush out any dust, debris or foreign objects that may get into the eye as well as to provide protective layer and lubricaiton to the eye to keep it moist and comfortable. Defects that cause a lack of sufficient aqueous matter in the acquous layer are a common cause of dry eye.
(3) lipid layer is the outmost layer of the term film and also aids to prevent dryness of the eye. The lipid layer is comprised of many lipids known as “meibum” or “sebum” that are produced by meibomian glands in upper and lawer eyelids. The outermost lipid layer is very thin, typically less than 250 nanometers (nm). The lipid layer provides a protective coating over the aqueous layer to limit the rate at which the aqueous layer evaportes. Blinking casues the ypper yelid to mall up aqueous matter and lipids as a ter film, thus proming a protective coating over the eye. A highe rate of evaporation of the aqueous layer can cause dryness of the eye. Thus, if the lipid layer is not sufficient to limti the rate of evaporation of the aqueous layer, dryness of the eye may result.
Sclera: provides a structure for teh eye that gives the eye a generally spherical shap. The sclera also gives the major surface portion of the eye its white color. A mammalian eye includes a cornea and sclera.
Diagnosis of Dry Eye: (see outline)
Treatment of Dry Eye Disease:
IL-20 Antagonists:
Change (20200048339) discloses methods for treating eye diseases such as dry eye disease (DED) and age-related macular degeneration (AMD) using an IL-20 antagonist that blocks the signaling pathway mediated by IL-20, for example, an antibody that binds IL-20 or an IL-20 receptor.
TNF-alpha Antagnoists:
Shamshiev (US20170107282) discloses TNF-alpha antagonists used to treat a TNF alpha-related disorder such as wet age-related macular degeneration or dry eye syndrome.