Two of the most commondiseases of eye are Blepharitis and Dry eye syndrome they both leads to lack ofnatural tear production. Blepharitis is an inflammation of the eyelids in whichthe eyes become red, irritated and itchy. Blepharitis is caused due to thegrowth of bacteria that live along the margins of the eyelids and at the baseof the eyelashes. Over time, these bacteria build up and create a structurecalled a biofilm.
This biofilm becomes a toxic environment like the plaque. Itscontents are a food source for parasitic eyelash mites. Proliferation ofDemodex mites increases the irritation and inflammation of the eyelids.
Blepharitis is considered as precursor of most of the eye diseases such as dryeye disease and meibomian glands dysfunction (MGD) 1. Dry eye syndrome whichis also known as kerato-conjunctivitis-sicca (KCS) is defined as a tear filmdisorder due to aqueous tear deficiency or excessive evaporation resulting inocular discomfort, visual disturbance, and tear film instability 2. A healthytear film is required for the proper functioning of eye the meibomiansecretions and tears are constantly produce to bathe, nourish, and protect theeye surface. The meibomian glands are present at the upper and lower eyelids.
These glands serve the function of oils secretion onto the surface of the eye.These oils help keep the tears from evaporating instantaneously. If meibomian glandsdysfunctions it causes dryness of the eye and eyelid inflammation. The oilglands become block with thickened secretions.
Chronically clogged glandseventually become unable to secrete oil that results in permanent changes inthe tear film and dry eyes. Blepharitis also causes tears gland(lacrimal glands) margin become inflamed whichdegrades the quantity and quality of tears, which causes more bacteria productionin biofilm and when the lacrimal glands fail to produce sufficient tears, dryeye results3 4. Dryness of the eye canalso be causes due to environmental, hormonal, physiological, contact lens wearand pathological causes. Dry eye syndrome is generally recognized as a disruptionof the Lacrimal Functional Unit (LFU), an integrated system comprising the lacrimal glands, ocularsurface (cornea, conjunctiva and meibomian glands) and lids, and the sensoryand motor nerves that connect them. The early methods of treatment involvedlubricating drops, gels or ointments, Anti-inflammatories.
These methods werenot long lasting and still there is no permanent cure of this disease. Treatmentsfor dry eye syndrome help to control the symptoms, but there is no permanentcure 5. Research work has beengoing on to understand the causes symptoms and effects of this disease in orderto treat dry eye syndrome it is important to fully understand the eye structureand what leads to dryness in the eye.