Tränenableitung

Tränenableitung refers to the anatomical pathway through which tears drain from the surface of the eye into the nasal cavity. This system is crucial for maintaining a clear ocular surface and preventing excessive tearing, or epiphora. The process begins with the lacrimal puncta, small openings located at the inner corner of the upper and lower eyelids. Tears are drawn into these puncta by capillary action and blinking.

From the puncta, tears flow into tiny tubes called canaliculi, which then converge to form the common canaliculus. This canaliculus empties into the lacrimal sac, a small reservoir situated in a groove on the side of the nose. The lacrimal sac then connects to the nasolacrimal duct, a longer tube that descends through a bony canal and opens into the nasal cavity, typically below the inferior turbinate.

Disruptions or blockages anywhere along this drainage pathway can lead to a variety of problems, including watery eyes, recurrent infections of the lacrimal sac (dacryocystitis), or the formation of a stye-like lump. Causes of blockage can range from congenital abnormalities, such as a narrow or absent nasolacrimal duct at birth, to acquired conditions like inflammation, infection, aging, or trauma. Treatment options depend on the location and severity of the obstruction and may include dacryocystorhinostomy (creating a new drainage pathway) or probing the tear ducts.