What are those two small holes in the upper and lower corners of the eyes for?

Don't talk nonsense without knowledge of human anatomy upstairs! Lacrimal glands and nasolacrimal ducts are invisible on the body surface! ! ~

That is the lacrimal punctum, which is an important structure in the process of tear excretion.

Tears come from the lacrimal gland. The lacrimal gland is located in the lacrimal gland fossa above the orbit, which is divided into two parts: the upper part is the orbit, also called the upper lacrimal gland, which is large and shaped like almond; The lower part is the eyelid, also called the inferior lacrimal gland, which is relatively small. There are 10 ~ 12 drainage tubes in the lacrimal gland, and the tears are discharged from these drainage tubes after they are produced.

After the tears are produced, they are excreted through the lacrimal passage. The lacrimal passage consists of lacrimal punctum, lacrimal canaliculus, lacrimal sac and nasolacrimal duct.

There is a tear spot on the inner side of the upper and lower eyelid margins. Tears enter the lacrimal canaliculus from the lacrimal punctum like a sewer, and enter the lacrimal sac through the canaliculus about 10mm long. Lacrimal sac is specially used to collect and store tears and prevent them from flowing out. There is a tube with a length of 12 ~ 24 mm and a diameter of 3 ~ 6 mm under the lacrimal sac, which is the nasolacrimal duct. Tears in the lacrimal sac enter the nasal cavity through the nasolacrimal duct. Therefore, when we order eye drops, we should press the nasal root with our fingers to prevent eye drops from flowing into the nasal cavity through the nasolacrimal duct.