Anatomy and Physiology of the Lacrimal System

The lacrimal system provides the ocular surface with the necessary fluid for lubrication, both for optimising the optical properties of the precorneal tear film and protecting the eye from foreign bodies, viral and microbial infection. A sophisticated system balances the amount of fluid production and drainage. The complete system is divided into two different parts: the secretory apparatus that produces and secrete the tear film onto the ocular surface (the lacrimal glands, the accessory lacrimal glands, the Meibomian glands, and the conjunctival goblet cells); the lacrimal drainage system that facilitates the flow of tears into the nasal cavity. The oculoplastic surgeon will typically manage disorders of the lacrimal drainage system. This chapter describes its fundamental anatomy and physiology.