The tarsi are firm, dense plates of connective tissue that serve as the structural support of the eyelids (Fig 9-22). The upper eyelid tarsal plate measures 10–12 mm vertically in the central eyelid; the lower eyelid tarsal plate measures 3–4 mm. The tarsal plates are typically 1 mm thick and taper at the ends to form rigid attachments to the periosteum through the medial and lateral canthal tendons. They may become horizontally displaced with age as a result of stretching of the medial and lateral supporting tendons. The meibomian glands within the tarsus are modified holocrine sebaceous glands.
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.