Page 151 - ONLINE PROCEEDING BOOK WSAVA 2017
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removed, an amniotic membrane or conjunctival graft can be placed. Until surgery can be performed, it is recommended to use lubricating eye ointment frequently to reduce mechanical irritation from trichiasis and/or incomplete blinking.
Canine limbal Melanomas
Although limbal or epibulbar melanomas are typically benign neoplasms, they may invade the cornea or intraocular structures. Limbal Melanomas are typically smooth and pigmented lesions, but can be also be amelanotic. These tumors occur in two age groups. The tumor tends to be more rapidly growing and invasive in the younger group (2–4 years) whereas they are more likely to be slowly growing in the older group (>8 years). They are usually located in the dorsal arc between the dorsomedial and ventrolateral limbus. German Shepherd, Golden Retriever, and Labrador Retriever appear predisposed and limbal melanomas may be associated with heavily pigmented dogs. They must be differentiated from intraocular or conjunctival melanomas. In older dogs with nonprogressive limbal tumors monitoring
may be adequate, but treatment is often required in younger dogs with fast growing tumors. Treatments include lamellar or full-thickness excision and grafting procedures, cryotherapy, and laser photocoagulation. Complete removal or removal with adjunctive cryotherapy is usually curative, while recurrence has been reported following laser therapy.
Feline corneal sequestra
This condition is characterized by an area of corneal degeneration with an amber (early phases) or brown- to-black (late phases) discoloration. Corneal sequestra can occur after chronic corneal ulcers or keratitis caused by infection with FHV-1 or by corneal irritation from entropion or trichiasis or iatrogenic damage (grid keratotomy). It can also appear as a primary stromal disease in Persians and Himalayans. The sequestra consists of necrotic cornea, but the cause of the corneal discoloration is currently unde ned. The necrotic cornea can be surgically removed by keratectomy and
a graft is most often placed. For super cial sequestra,
a graft may not be required, but covering the defect
with a soft contact lens and/or tarsorrhaphy during healing is usually recommended to reduce chances
of recurrence. Conjunctival grafts may help to prevent recurrence. Corneoconjunctival transposition, porcine small intestinal submucosa graft or amniotic membrane or heterologous corneal graft transplantation can also be performed following the keratectomy. It is important to treat the underlying disease process in order to prevent recurrence following surgery.
An Urban Experience
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