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tvpjournal.com | July/August 2015 | TodAy's VeTerinAry PrAcTice obserVATions in oPhThAlmology Peer reviewed 77 resulted from Th-1 lymphocytic cell, immune- mediated attack on melanocytes in the uvea and skin. The syndrome is characterized by bilateral panuveitis accompanied by facial poliosis and vitiligo. 13,14 loss of pigmentation of the nose and eyelids is the primary clinical sign observed, and patients are often presented due to sudden blindness or gradual vision loss. dogs are usually affected in young adulthood, and ocular lesions are seen before dermatologic lesions. 6 dermatologic lesions usually affect the mucocutaneous junctions, with ulceration, crusting, and hypopigmentation of the eyelids. 13-15 The condition is commonly bilateral, but unilateral disease has been reported. 16 Arctic breeds are overrepresented for this condition, including the s iberian husky, Alaskan malamute, and Akita, but the condition has been reported in golden retrievers, rottweilers, shetland sheepdogs, and other breeds. 6,13,14,16 Diagnosis. Key ocular examination fndings are listed in Table 1. no specifc diagnostic test is available; fndings on routine laboratory tests, including blood work, are typically unremarkable. The best information is provided by: • clinical signs and breed predisposition • histopathologic examination of skin biopsy, which reveals lichenoid dermatitis, histiocytes, and giant cell infiltration, as well as decreased levels of melanin in the epidermis and hair follicles. Treatment. initial therapy involves immuno- suppressive doses of oral prednisone with or without azathioprine and/or cyclophosphamide. cyclosporine can also be used as adjunctive therapy, but the patient's size is a limiting factor in its use. The oral steroid dose should be tapered after 5 weeks of therapy (once azathioprine completes the lag period). Topical corticosteroids can be used for anterior segment lesions. Therapy is lifelong. Eyelid Neoplasia Description. many different neoplasms affect the canine eyelids; most are locally invasive lesions that respond fairly well to conservative surgical procedures. eyelid neoplasms can produce focal or diffuse blepharitis, depending on the location on the eyelid and behavior of the neoplasm. benign neoplasms are more common than malignant neoplasms, and epithelial neoplasms are more frequent than mesenchymal neoplasms. 7 most eyelid neoplasms occur in dogs older than 10 years of age, with the superior lid affected more often than the inferior lid. 7 common eyelid neoplasms are described in Table 2 (page 78); however, mast cell tumors, histiocytomas, and hemangiomas/ hemangiosarcomas also occur frequently. Diagnosis. diagnosis is based on appearance of eyelid neoplasm and invasiveness, while histopathologic examination of neoplasm after resection allows defnitive diagnosis. Treatment. surgical excision (most common) and/or cryotherapy are performed. consider debulking neoplasm if full surgical removal is not indicated. surgical procedures depend on neoplasm size and involvement of lid margin: 7,17 • eyelid masses involving up to 25% of the lid: Four-sided defect wedge (house shape) and V wedge are the best surgical procedures, which are performed by scissors and/or scalpel and should extend at least one meibomian gland beyond the Table 1. Key Ocular examination Findings: Uveodermatologic syndrome • Presence of aqueous fare • Signs of uveitis, bullous retinal detachments, secondary cataract formation, and glaucoma • Progressive depigmentation of iris and retinal pigment epithelium • Development of hyper-refective tapetal fundus, with vascular attenuation and optic nerve atrophy • Gradual or rapid development of vitiligo and poliosis (ulcerative) restricted to the face, usually involving the eyelids FIGURE 11. Thirteen-year-old spayed female Labrador retriever with a meibomian gland adenoma. Note the mass arising from the superior eyelid, erupting through the eyelid margin to the palpebral conjunctiva. The mass is causing local irritation characterized by conjunctival hyperemia and epiphora. Surgical correction, which was curative, with a 4-sided defect wedge was performed with careful consideration of the dorsal nasolacrimal puncta. Courtesy Dr. Ellen B. Belknap