Abstract:

Objective To investigate the characteristics of pigmented rabbit retinal vein occlusion induced by photochemical method. Methods Sixteen healthy pigmented rabbits were randomly divided into group A and group B, with 8 rabbits in each group. Laser photocoagulation with double-frequency laser (532 nm) on the trunk retinal vein was performed after the injection of Rose Bengal solution (50 mg/kg) via ear marginal vein. Laser reference parameters of group A were as follows: power 150 mW for 15 shots and then 300 mW for another 15 shots. Laser reference parameters of group B were as follows: power 150 mW for 40 shots and then 300 mW for another 40 shots. Fundus photograph and fundus fluorescein angiography were performed before photocoagulation and 15 min, 1 d, 3 d, 7 d, 14 d and 28 d after photocoagulation. One rabbit was sacrificed in each group 1 d after photocoagulation, and the rest were killed 28 d after photocoagulation for light microscopy. Results Retinal vein occlusion models were successfully established in both groups, and retinal artery occlusion was also induced in group B 1 d after photocoagulation. Seven days after photocoagulation, venous recanalization was detected in all occluded veins in group A and in part of the occluded veins in group B. Histopathological examinations indicated that venous thrombus formed in retinal veins in both groups 1 d after photocoagulation, and there was retinal atrophy around the papillary disc 28 d after photocoagulation. Conclusion It is convenient to establish rabbit model of retinal vein occlusion by Rose Bengal photochemical method. With the increase of photocoagulation shots on regional retinal vein, the retinal artery could be occluded as well.

Key words: photochemistry, retinal vein occlusion, animal model