Any abnormality of any one of the three layers of tears produces an unstable tear film, resulting in symptoms of dry eyes. Decreased tear or excessive evaporation edit Keratoconjunctivitis sicca is usually due to inadequate tear production from lacrimal hyposecretion or to excessive tear evaporation. The aqueous tear layer is affected, resulting in aqueous tear deficiency (ATD). The lacrimal gland does not produce sufficient tears to keep the entire conjunctiva and cornea covered by a complete layer. This usually occurs in people who are otherwise healthy. Increased age is associated with decreased tearing. This is the most common type found in postmenopausal women. Causes include idiopathic, congenital alacrima, xerophthalmia, lacrimal gland ablation, and sensory denervation. In rare cases, it may be a symptom of collagen vascular diseases, including relapsing polychondritis, rheumatoid arthritis, granulomatosis with polyangiitis, and systemic lupus erythematosus. Sjögren syndrome and...
Comments
Post a Comment