Keratoconjunctivitis sicca is really a disorder of the tear glands that results in insufficient aqueous tear production along with a correspondingly dry cornea. The tear film contains less of the aqueous layer and more of the mucus layer. In consequence, the classic manifestation of dry eye is really a thick, stringy, mucoid to mucopurulent discharge. Because this kind of discharge may also be seen with conjunctivitis, dogs with dry eye might be mistakenly treated for chronic conjunctivitis for very long periods with little if any improvement.
In your dog with dry eye, the intense, glistening sheen normally seen in the eye is replaced with a lackluster appearance in that the cornea is dry, dull, and opaque. Recurrent bouts of conjunctivitis are normal. Eventually the cornea becomes ulcerated or develops keratitis. Blindness may ensue.
Dry eye might have several causes. Immune-mediated diseases seem to play a significant role. Other cases are idiopathic - that is, the reason isn't known. Breeds predisposed to dry eye include Bulldogs, Cocker Spaniels, Lhasa Apsos, West Highland White Terriers, yet others. Some specific conditions that predispose your dog to dry eye include:
Problems for the nerves that innervate the lacrimal glands. A branch of the facial nerve that activates the tear glands passes with the middle ear. Infections in the middle ear can harm this branch, affecting the tear glands as well because the muscles on that side of the face. In this example, the alternative eye isn't affected.
Problems for the tear glands themselves. Partial or complete destruction of tear glands can follow systemic diseases for example canine distemper, Addison's disease, and immune-mediated diseases for example rheumatoid arthritis symptoms. Bacterial blepharitis or conjunctivitis can destroy the tear glands or occlude the little ducts that carry the tears in to the eye. Numerous sulfonamide medicine is toxic to tear glands. Tear gland injuries might be partially reversible when the underlying cause is eliminated.
Congenital absence of the tear glands is rare, but may occur in the smaller breeds.
Removal of the third eyelid or even the lacrimal gland mounted on it. Detecting dry eye is created by measuring the amount of tears. The Schirmer tear test involves placing commercial filter paper strip in to the tear pool in the inner corner of the dog's eye and leaving it for one minute to determine how much of the strip is wetted. Normally the strip should be wet to some distance of 20mm. In dogs with dry eye, the strip wets under 10mm (often under 5mm).
Treatment: For several years, the frequent use of artificial tears was the only real treatment readily available for dry eye. But FDA approval of ophthalmic cyclosporin has revolutionized treatment and greatly improved results. Cyclosporin is definitely an immunosuppressive drug that reverses immune-mediated destruction of the lacrimal glands.
Cyclosporin ointment is put on the top of the involved eye. The regularity of application should be based on your veterinarian. The result isn't immediate. Artificial tears and topical antibiotics should be continued before Schirmer tear test indicates that the amount of tears is adequate.
Treatment is life-long. Interrupting cyclosporin as low as Twenty four hours causes symptoms to reappear in 90 % of dogs. This is often reversed by resuming treatment.
When harm to the lacrimal glands leaves little if any functioning tissue, cyclosporin isn't likely to work. Artificial tears (drops and ointments) prescribed by your veterinarian must then be instilled in to the dog's eyes many times each day for a lifetime. Ointments are cheaper and don't need to become applied as often as drops. Saline drops shouldn't be used simply because they aggravate the issue by washing away the lipid layer of the tear film.
A topical mucolytic agent containing acetylcystine might be recommended to lessen heavy mucus accumulation. Topical antibiotics are indicated whenever the discharge of mucus becomes purulent. Topical corticosteroids might be prescribed by your veterinarian in some circumstances to diminish inflammation.
In the presence of corneal ulceration, corticosteroids are contraindicated simply because they predispose your dog to rupture of the cornea. Surgical treatment can be viewed as like a last measure when medical management fails. The operation involves transplanting the duct of the parotid salivary gland up in to the corner of the eye.
The saliva takes the area of the tears. The operation has several significant disadvantages. One is that the amount of tears might be more compared to drainage system are designed for. This could result in a watery eye and also the accumulation of nutrients on the cornea and face.
Our website is not responsible for the information contained by this article. Articleinput.com is a free articles resource thus practically any visitor can submit an article. However if you notice any copyrighted material, please contact us and we will remove the article(s) in discussion right away.
Note: This article was sent to us by: Norma Richards at 05132011
1. Golden retrievers need to exercise and love to take walks
All articles are property of their respective authors. Please read our Privacy Policy!
© 2009 ArticleInput.com.
Partners: Damenmode