The vitreous has few cells and no blood vessels. However, the collagen fibrils of the vitreous can provide a scaffold for glial and fibrovascular tissue from the retina and uveal tract to grow and extend into the vitreous to proliferate as membranes. These membranes usually have a contractile component, which can lead to traction on the retina and ciliary body.
Excerpted from BCSC 2020-2021 series: Section 4 - Ophthalmic Pathology and Intraocular Tumors. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.