| Tarsus | |
|---|---|
 The tarsi and their ligaments. Right eye; front view. | |
 The right eye in sagittal section, showing the fascia bulbi. (Tarsi labeled at right.) | |
| Details | |
| Identifiers | |
| Latin | tarsus superior, tarsus inferior |
| TA98 | A15.2.07.038 A15.2.07.039 |
| TA2 | 6827,6829 |
| FMA | 59086 |
| Anatomical terminology | |
Thetarsi (sg.:tarsus) or tarsal plates are two comparatively thick, elongated plates ofdense connective tissue, about 10 mm (0.39 in) in vertical dimension for the upper eyelid and 5 mm for the lower eyelid; one is found in eacheyelid, and contributes to its form and support. They are located directly above thelid margins.[1] The tarsus has a lower and upper part making up thepalpebrae.
Thesuperior tarsus (tarsus superior; superior tarsal plate), the larger, is of asemilunar form, about 10 mm (0.4 in) in breadth at the center, and gradually narrowing toward its extremities. It is adjoined by thesuperior tarsal muscle.
To the anterior surface of this plate the aponeurosis of thelevator palpebrae superioris is attached.
Theinferior tarsus (tarsus inferior; inferior tarsal plate) is smaller, is thin, is elliptical in form, and has a vertical diameter of about 5 mm (0.2 in). The free or ciliary margins of these plates are thick and straight.
The attached or orbital margins are connected to the circumference of the orbit by theorbital septum.
The lateral angles are attached to thezygomatic bone by thelateral palpebral raphe.
The medial angles of the two plates end at thelacrimal lake, and are attached to the frontal process of themaxilla by themedial palpebral ligament).
Thesulcus subtarsalis is a groove in the inner surface of each eyelid.
Along the inner margin of the tarsus are modified sebaceous glands known as tarsal glands (ormeibomian glands), aligned vertically within the tarsi: 30 to 40 glands in the upper lid, and 20 to 30 in the lower lid, which secrete a lipid-rich product which helps keep the lacrimal secretions or tears from evaporating too quickly, thus keeping the eye moist.[2]
This article incorporates text in thepublic domain frompage 1025 of the 20th edition ofGray's Anatomy(1918)
