Lymphatic System of the Orbit
The presence of a human orbital lymphatic system has not been established. However, experimental studies in monkeys have identified orbital lymphatic vessels by means of enzyme histochemistry and electron microscopy in the conjunctiva, lacrimal glands, and dura and arachnoid of the optic nerve. Despite the controversy, it is likely that human orbital lymphatics exist and may clinically explain the drainage of orbital edema fluid and the existence of orbital lymphatic malformations (lymphangiomas).
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.