The effects of mitomycin-C on intraocular pressure (IOP), facility of outflow (C), and Tenon's capsule fibrosis were studied over 60 days in 10 clinically normal dogs. A 1-piece, silicone glaucoma implant was surgically implanted into both eyes; the filtration site of one eye was treated with a single, 5-minute intraoperative application of mitomycin (0.5 mg/ml), and the fellow eye was treated in a similar manner with balanced salt solution. There were no significant differences in preoperative IOP or C-values between treatment groups. Mean IOP in eyes of both groups initially decreased from the preoperative value, but returned to the baseline value by day 21. Mean facility of aqueous outflow (C-value) increased in all eyes during the first 14 days (mitomycin-C-value = 2.26 +/- 0.72; control C-value = 2.38 +/- 0.81), then reached a plateau that was significantly higher than the baseline value in mitomycin (P = 0.039) and control (P = 0.041) eyes. Histologic evaluation revealed all implants surrounded by a connective tissue capsule composed of regular dense collagen and fibroblasts that was significantly (P = 0.003) thinner in the mitomycin-treated (scleral side = 167 +/- 62 micrometer; conjunctival side = 122 +/- 41 micrometer) than the control (scleral side = 261 +/- 92 micrometer; conjunctival side = 180 +/- 48 micrometer) group. There were, however, no significant differences in IOP or C-values between groups at any postoperative time interval. Results of this study indicate that intraoperative treatment with mitomycin suppresses, but does not prevent fibrosis around silicone filtering implants.

TVT, also known as infectious sarcoma, venereal granuloma, transmissible lymphosarcoma or sticker tumour is a benign reticuloendothelial tumour that affects particularly mucosa of external genital organs and rarely internal genital organs in dogs of both genders. TVT is usually transmitted by coitus but also can be transmitted by licking, sniffing, biting,and scrabbling of the tumour affected area or through damaged skin of mucosa. Transmissible venereal tumour (TVT) is usually observed in stray animals live in tropical and subtropical lands. The affected animals are usually within 9-13 months of age and with high sexual activity. Tumour is frequently located in posterior vagina and vestibulovaginal junction. The averagechromosome count of TVT cells is 59 (57- 64). TVT specific antibodies were found in blood samples of affected animalswhich suggest that they may have a role in natural regression mechanism. The primary objective of tumour treatment is total elimination by surgery, radiotherapy, immunotherapy and/or chemotherapy. Controlling of the disease is very difficult because stray dogs are carriers.