November 8, 2018

Histopathological and Immunohistochemical Features of Vitreoretinopathy in Shih Tzu Dogs

A study looking into the abnormalities surrounding ocular vitreoretinopathy in Shih Tzu Dogs

Shih Tzus are a very popular breed that are plagued by an array of different medical issues, especially ocular diseases. However, the pathology of these diseases have yet to be investigated heavily. The most common vision problems in Shih Tzus are retinal detachment (RD) and progressive retinal atrophy, an “inherited, bilateral, progressive disease of the retinal photoreceptors that ends in blindness” (Glaze, 2011). Vitreoretinopathy occurs as a complication of RD. The goal of this study is to examine histopathological and immunohistochemical features of vitreoretinopathy and to propose a cause to the ocular disease.


The study used fifty cases of Shih Tzus with ocular vitreoretinopathy. Immunohistochemistry was performed to assess the microscopic features of the globes, most of which were removed due to glaucoma.  Out of the 50 dogs, 25 were male, 23 were female, and 2 were of an undetermined gender. The mean age was around 10. All eyes looked similar but the most aggressive abnormality “were the presence of extensive RD associated with retinal atrophy and extensive retinal tear” (Papaioannou and Dubielzig). The results show the major pathological changes in these conditions are retinal detachment and excessive retinal tears (Papaioannou and Dubielzig). The mean age of 10 support the prior claims that this was an age-dependent disease. Humans are similar in the way that RD is also age-related.

Papaioannou, Nikolaos G., Richard R. Dubielzig, 2013. Histopathological and Immunohistochemical Features of Vitreoretinopathy in Shih Tzu Dogs. Journal of Comparative Pathology, 148: 230-235.
Reviewed by: Aja Jones. 08 November 2018.