eye disorders
Keratoconjunctivitis Sicca
Symptoms and Signs of Keratoconjunctivitis Sicca
Patients report itching; burning; a gritty, pulling, or foreign body sensation; or photosensitivity. A sharp stabbing pain, eye strain or fatigue, and blurred vision may also occur. Some patients note a flood of tears after severe irritation. Typically, symptoms fluctuate in intensity and are intermittent. Certain factors can worsen symptoms: Prolonged visual efforts (eg, reading, working on the computer, driving, watching television) Local environments that are dry, windy, dusty, or smoky Certain systemic drugs, includingisotretinoin, sedatives (eg, that have anticholinergic effects), diuretics, beta-blockers, oral contraceptives, and all anticholinergics (including antihistamines and many gastrointestinal drugs) Dehydration Symptoms lessen on cool, rainy, or foggy days or in other high-humidity environments, such as in the shower. Recurrent and prolonged blurring and frequent intense irritation can impair daily function. However, permanent impairment of vision is rare. With both types, the conjunctiva is hyperemic, and there is often scattered, fine, punctate loss of corneal epithelium ( Superficial Punctate Keratitis ), conjunctival epithelium, or both. When the condition is severe, the involved areas, mainly between the eyelids (the intrapalpebral or exposure zone), stain with With the aqueous tear-deficient type, the conjunctiva can appear dry and lusterless with redundant folds. With the evaporative type, abundant tears may be present as well as foam at the eyelid margin. Very rarely, severe, advanced, chronic drying leads to significant vision loss due to keratinization of the ocular surface or loss of corneal epithelium, leading to sequelae such as scarring, neovascularization, infections, ulceration, and perforation. 