Tårkörtlarna

Tårkörtlarna, also known as lacrimal glands, are exocrine glands responsible for producing the watery component of tears. These glands are essential for maintaining the health and lubrication of the ocular surface. There are two main types of tårkörtlarna: the main lacrimal gland and the accessory lacrimal glands. The main lacrimal gland is located in the superolateral aspect of each orbit, within the lacrimal fossa of the frontal bone. It is a compound tubuloacinar gland that produces a serous secretion rich in water, electrolytes, and proteins like lysozyme and antibodies.

The accessory lacrimal glands are smaller and are distributed throughout the conjunctiva and eyelids. These include the glands of Krause and Wolfring, which contribute to the basal tear film, providing constant lubrication and nourishment to the cornea and conjunctiva. Tears produced by these glands serve multiple functions. They keep the cornea moist, preventing dryness and damage. They also wash away debris and foreign particles, protecting the eye from infection. Furthermore, tears contain nutrients that nourish the avascular cornea.

The flow of tears is a continuous process. Tears are produced constantly, spread across the eye by blinking, and then drain through the lacrimal puncta, lacrimal canaliculi, lacrimal sac, and finally into the nasolacrimal duct, emptying into the nasal cavity. This drainage system explains why crying often leads to a runny nose. Disruptions to tårkörtlarna's function can lead to various eye conditions, such as dry eye syndrome when tear production is insufficient, or excessive tearing (epiphora) when drainage is impaired or tear production is overstimulated.