Conjunctivochalasis, also known as Mechanical Dry Eye (MDE), is a common eye surface condition characterized by the presence of excess folds of the conjunctiva located between the globe of the eye and the eyelid margin. Symptoms
Symptoms range from dry eye, epiphora and irritation to localized pain, foreign body sensation, subconjunctival hemorrhage and ulceration. Symptoms are often made worse by vigorous blinking. Causes
Most Conjunctivochalasis is thought to be caused by both a gradual thinning and stretching of the conjunctiva that accompanies age and a loss of adhesion between the conjunctiva and underlying sclera as the result of dissolution of Tenons capsule. The resulting loose, excess conjunctiva may mechanically irritate the eye and disrupt the tear film and its outflow, leading to dry eye and excess tearing. A correlation may also exist between inflammation in the eye and conjunctivochalasis, though it is unclear whether this correlation is causal. Conjunctivochalasis may be associated with previous surgery, blepharitis, meibomian gland disorder (MGD), Ehlers-Danlos Syndrome and aqueous tear deficiency. Diagnosis
Because the disorder often occurs in people with typical dry eye symptoms, it can be difficult to readily distinguish the discomfort caused by the dry eye from that directly related to the redundant conjunctiva. Mechanical dry eye should not be confused with aqueous tear deficiency dry eye or delayed tear clearance. Mechanical dry eye patients complain of blurry vision and pain that tend to be worse when looking down such as while reading.
Demeclocycline (INN, BAN, USAN, brand name Declomycin) is a tetracycline antibiotic which was derived from a mutant strain of Streptomyces aureofaciens. Uses
Demeclocycline is officially indicated for the treatment of various types of bacterial infections. It is used as an antibiotic in the treatment of Lyme disease, acne, and bronchitis. Resistance, though, is gradually becoming more common, and demeclocycline is now rarely used for treatment of infections.It is widely used (though off-label in many countries including the United States) in the treatment of hyponatremia (low blood sodium concentration) due to the syndrome of inappropriate antidiuretic hormone (SIADH) when fluid restriction alone has been ineffective. Physiologically, this works by reducing the responsiveness of the collecting tubule cells to ADH.The use in SIADH actually relies on a side effect; demeclocycline induces nephrogenic diabetes insipidus (dehydration due to the inability to concentrate urine).The use of demeclocycline in SIADH was first reported in 1975, and, in 1978, a larger study found it to be more effective and better tolerated than lithium carbonate, the only available treatment at the time. Demeclocycline used to be the drug of choice for treating SIADH. Meanwhile it might be superseded, now that vasopressin receptor antagonists, such as tolvaptan, became available. Contraindications
Like other tetracyclines, demeclocycline is contraindicated in children and pregnant or nursing women. All members of this class interfere with bone development and may discolour teeth. Side effects and interactions
These are similar to those of other tetracyclines. Skin reactions with sunlight have been reported.