Dacryocystitis is an infection of the tear sac that lies between the inner corner
of the eyelids and the nose.
The lacrimal excretory system is prone to infection and inflammation for various reasons. This mucus membrane-lined tract is contiguous with 2 surfaces (conjunctival and nasal mucosal) that are normally colonized with bacteria. The functional purpose of the lacrimal excretory system is to drain tears from the eye into the nasal cavity. Stagnation of tears in a pathologically closed lacrimal drainage system can result in dacryocystitis.
Acquired dacryocystitis can be acute or chronic. Acute dacryocystitis is heralded by the sudden onset of pain and redness in the medial canthal region. An insidious onset of epiphora is characteristic of chronic inflammation or infection of the lacrimal sac.
A special form of inflammation of the lacrimal sac is that of congenital dacryocystitis, the pathophysiology of which is intimately related to the lacrimal excretory system embryogenesis.
Dacryocystitis has long been noted to occur more frequently on the left side than the right side. In many instances, the nasolacrimal duct and lacrimal fossa formed a greater angle on the right side than the left side.