Related Experiment Video
Updated: Jun 17, 2026

Quail Chorioallantoic Membrane - A Tool for Photodynamic Diagnosis and Therapy
Published on: April 28, 2022
[Experimental study of vitreoretinal proliferation inhibition by the use of hypericin]
Roberto Augusto Fernandes Machado1, Antonio Marcelo Barbante Casella, Marcus Rudolph Malaguido
1Universidade Estadual de Londrina, Londrina, PR, Brasil.
Purpose:
To produce proliferative vitreoretinopathy (PVR) in an animal ocular trauma model. To evaluate the inhibition of (PVR) emergence and progression by hypericin.
Methods:
Experimental Study. Nineteen pigmented male adult rabbits weighing between 2,000 and 3,000 grams were used in this study. All of them were submitted to trauma model with dispase and retinal diathermy to induce PVR membranes formation. They were randomly assigned to receive hypericin (10 microM in 0.1 ml) or saline solution (0.1 ml) as placebo. They were evaluated clinically in the seventh, fourteenth, twenty-first and twenty-eighth postoperative days with indirect ophthalmoscopy and digital color retinography. The PVR degree was classified according to Hida (0 to 7).
Results:
Membranes formation was present in 79% of the eyes; being 100% in the eyes of placebo group and 60% in the eyes of treatment group (hypericin). The comparison between PVR phases averages within the groups showed a statistically significant difference between the two groups, with a p value of 0.0321 for Wilcoxon test.
Conclusions:
The trauma model with dispase and retinal diathermy produces vitreoretinal membranes. Hypericin was considered effective in PVR emergence and progression decrease.

