Blood-retinal barrier after blunt trauma to the eye.

The competence of blood retinal barrier at the level of retinal pigment epithelium (RPE) and retinal capillaries was studied 30 min, 24 h, 3 days, and 7 days after experimental blunt eye injury in the pig, using horseradish peroxidase (HRP). Leakage of HRP into the outer retinal layers was observed in association with disrupted RPE in the first three days after injury. No HRP leakage was seen 7 days after the trauma and the retinal vessels remained competent throughout the study. It is suggested that extracellular edema occurs in the early stages of commotio retinae due to the disruption of blood retinal barrier at the level of the RPE.