Preputial diverticulum dilation in a Goettingen minipig.

Preputial dilation is an infrequently reported condition in pigs. The pathophysiology and etiology is unclear. Causes for diverticulum dilation are proposed to be chronic preputial diverticulitis with subsequent fibrosis of the preputial cavity, phimosis of the preputial orifice or the preputial diverticulum, but the large majority of cases are reportedly idiopathic in nature. Surgical interventions include ablative procedures, but many cases are not treated because of an assumed lack of clinical relevance in pigs not used for breeding. We report a case of progressive preputial dilation that recurred after surgical intervention. Histopathological examination revealed no primary inflammatory condition, contrary to literature suggesting a role for inflammatory mediators in pathogenesis. Phimosis of the preputial orifice was noted post mortem and might be a contributing factor. These findings partially contradict the current assumptions in regards to pathophysiology and treatment choices in the literature and warrant further investigation into alternative therapeutic interventions for this condition.

A retrospective study of the clinical, histological, and immunohistochemical manifestations of 5 dogs originally diagnosed histologically as necrotizing scleritis.

PURPOSE: To describe the clinical, histological, and immunohistochemical manifestations of canine necrotizing scleritis. METHODS: A retrospective examination of the clinical records and samples of ocular tissues from five dogs with a histological diagnosis 'necrotizing scleritis' was completed. Archived, formalin-fixed, paraffin-embedded samples and two control globes were stained with hematoxylin and eosin, Gram, periodic acid-Schiff (PAS) and Masson trichrome stains, and they were immunohistochemically labeled for CD3, CD18, and CD20. RESULTS: Of the five cases reviewed, only two could be confirmed as idiopathic necrotizing scleritis. The other three cases were retrospectively diagnosed as unilateral focal, non-necrotizing scleritis, one as episcleritis and the third was scleritis secondary to a proptosed globe based on our retrospective clinical, histological, and immunohistochemical evaluations. In these two cases, idiopathic necrotizing scleritis manifested as a bilateral, progressive, inflammatory disease of the sclera and cornea that induces significant uveitis. Light microscopic examination confirmed collagen degeneration and granulomatous inflammation. There was no evidence for an infectious etiology based on Gram's and PAS stainings. Immunohistochemical labeling revealed a predominance of B cells in idiopathic, bilateral necrotizing scleritis. Tinctorial staining abnormalities with Masson's trichrome stain were present in scleral collagen of the two cases with idiopathic necrotizing scleritis as well as a case of secondary traumatic scleritis. CONCLUSIONS: Based on a limited number of cases, idiopathic canine necrotizing scleritis shares similar histopathological features with non-necrotizing scleritis and episcleritis; however, necrotizing scleritis is B-cell-dominated and bilateral, and significant collagen alterations manifest with Masson's trichrome stain.

The effect of UV-blocking contact lenses as a therapy for canine chronic superficial keratitis.

OBJECTIVE: To evaluate the effect of UV-blocking soft contact lenses in treatment for chronic superficial keratitus (CSK). METHODS: Twenty six dogs with CSK were treated continuously with UV-blocking contact lenses for 6 months. A contact lens was placed on one eye of each dog; the other eye remained without a lens as a control eye. After this primary study, five of the dogs were further treated and they wore then contact lenses in both eyes. Continuously, all patients were concurrently treated topically with cyclosporine. The contact lenses were changed every 4 weeks and an ophthalmic examination performed. Evaluation criteria included corneal alterations as pigmentation, edema, pannus and vascularization. To determine the transmittance characteristics of the contact lenses before and after use, 32 contact lenses were measured with a UV-vis-NIR spectrophotometer. RESULTS: Pigmentation increased in eyes wearing lenses and in control eyes over the evaluation period of 6 months. Corneal edema increased in the eyes wearing lenses, but remained unaffected in the control eyes. A significant difference in the incidence of pannus and the extent of corneal vascularisation could not be evaluated. Adverse effects were noted in six cases (corneal edema and vascularisation, conjunctivitis, blepharospasm). All new lenses studied reduced UV-radiation to a safe level, whereas used lenses did not maintain their transmittance characteristics. CONCLUSIONS: No positive effect of UV-blocking contact lenses could be proven with the study design used.