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  • Author or Editor: Robert L. Peiffer x
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Abstract

Objective—To examine the morphologic changes in the anterior lens capsule and lens epithelium of canine eyes with cataracts.

Sample Population—Anterior lens capsules from the eyes of 25 dogs with cataracts and from an additional 10 canine globes with lenses subjectively assessed to be normal.

Procedure—Thickness of each anterior lens capsule was measured by use of a digital microscopic camera and imaging software. All 25 capsules from eyes with cataracts were submitted for light microscopy; 4 were also submitted for electron microscopy.

Results—Thickness of the anterior lens capsule increased with age for the normal lenses and the lenses with cataracts; the change with age was similar for both groups. Light microscopy revealed fibrous metaplasia of lens epithelial cells in 7 of 25 anterior lens capsules with focal thickenings of the posterior aspect of the capsule. Electron microscopy revealed deposition of collagen and basement membrane-like material by fibroblast-like cells.

Conclusions—Results indicate that thickness of the anterior lens capsule in dogs increases with age and that this increase in thickness is not significantly different between normal lenses and lenses with cataracts. In addition, epithelial cells from lenses with cataracts may undergo metaplasia to form plaques composed of fibrous tissue and ectopic basement membrane produced by epithelial cells. (Am J Vet Res 2000;61:1517–1519)

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in American Journal of Veterinary Research

  • Clinical signs and histologic findings associated with dematiaceous fungal infections of the ocular tissues can be variable.

  • Dematiaceous fungi should be considered in the differential diagnoses list of exogenous causes of ocular infections, such as endophthalmitis, orbital cellulitis, and keratitis.

Free access
in Journal of the American Veterinary Medical Association

Summary

Histopathologic findings in 158 globes obtained from 139 cats by enucleation or at necropsy, with histopathologic diagnosis of uveitis, were compared, and morphology was correlated with clinical and/or histopathologic diagnosis. The most common morphologic feature was a lymphocytic-plasmacytic anterior uveal infiltrate that was either diffuse or nodular; specific cause could not be associated with this nongranulomatous anterior uveitis. In decreasing order of frequency, other common causes of uveitis in cats included feline infectious peritonitis; FeLV-associated lymphosarcoma; trauma; and lens-induced uveitis.

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective

To examine the proliferative abilities of growth factors known to participate in wound healing on feline lens, iris pigment, ciliary, and retinal pigment epithelium cultured in vitro.

Animals

8 clinically normal cats.

Procedure

Iris pigment, lens, ciliary, and retinal pigment epithelia of normal eyes of cats were isolated and cultured. Morphologic characteristics of primary cell cultures were studied by light and electron microscopy. Subcultures of epithelial cells were exposed to media supplemented with 0.5% fetal bovine serum plus various combinations of insulin and/or growth factors, including transforming growth factor-α, epidermal growth factor, acidic fibroblast growth factor, and basic fibroblast growth factor. Growth promoting effects were evaluated by counting with an electronic cell counter.

Results

Cells retained many of the morphologic characteristics of in vivo cells. Cell proliferation assays indicated that transforming growth factor-α stimulated lens and ciliary epithelial cell growth, and epidermal growth factor enhanced lens and iris pigment epithelial cell growth. Acidic fibroblast growth factor had proliferative effects on lens, iris pigment, and ciliary epithelium. Basic fibroblast growth factor was the most potent stimulator of all mitogens used, and caused substantial proliferation in all cell types. Insulin alone stimulated lens and ciliary epithelial proliferation but, combined with other growth factors, had a synergistic effect with those causing cell proliferation, except acidic fibroblast growth factor with iris pigment epithelium.

Conclusion

Morphologic studies support the argument that pigment-producing cells are involved in feline ocular sarcoma. Growth factor studies indicated that ciliary epithelium has the most profound proliferative effect of all growth factors used. These data may help guide future studies in determining the cell of origin for feline ocular sarcoma. (Am J Vet Res 1996;57:1748–1752)

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in American Journal of Veterinary Research