Lacrimal gland

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The lacrimal glands are paired glands, one for each eye, that secrete the aqueous layer of the tear film.

1 Anatomy
2 Structure
3 Innervation
4 Blood Supply
5 Additional images
6 See also
- 6.1 Disorders

[edit] Anatomy

Each lacrimal gland is divided into orbital and palpebral portions by the aponeurosis of the Levator palpebrae superioris muscle, the portions are continuous with each other. The orbital portion is the largest of the portions, and its convex superior surface is lodged in the lacrimal fossa of the orbit.

For the smaller palpebral portion, its inferior surface lies close to the eye; if the upper eyelid is everted, the palpebral portion can be seen. The orbital portion contains fine interlobular ducts that unite to form 3 - 5 main excretory ducts, joining 5 - 7 ducts in the palpebral portion before the secreted fluid may enter on the surface of the eye.

[edit] Structure

The lacrimal gland is a tubuloacinar gland, it is made up of many lobules separated by connection tissue, each lobule contains many acini. Each acini is a tubuloacinar unit, and they consist of a mass of cells with their apices pointed to a central lumen. The central lumen of many of the units united to form intralobular ducts, and then unite to form interlobular ducts.

[edit] Innervation

The sensory innervation to the lacrimal gland is from the lacrimal nerve of the trigeminal nerve. The parasympathetic nerve supply originates from the lacrimal nucleus of the facial nerve in the pons, and travel via the pterygopalatine ganglion and maxillary nerve to innervate the gland. The sympathetic postganglionic fibres originates from the superior cervical ganglion and travels through the same route as the parasympathetic fibres from the pterygopalatine ganglion.