Why people often shed tears: under normal circumstances, after each blink eyes, the tear secreted by lacrimal gland and deputy lacrimal gland will balance by the excretory system of tear or evaporation. The surface optical of the eye is filled with tears, which keeps the eye moist and comfortable, while we do not feel tears. When lacrimal glands secreted too much or there's something wrong with its excretory system so that we would feel our tears. Many factors would lead us secrete too much tears, including our mental stimulation.

The reflection stimulus by foreign matter; the effect of cholinergic drugs and anticholinergic enzyme, etc. some kinds of diseases such as glaucoma, eyelids, conjunctiva and irisitis. Or the trigeminus and the facial nerves are stimulated. If your eyes secrete exessive lacrimal fluid which could hardly evaprate or excrete, your tears will keep falling all the time.

And there are something wrong with your excretory system of your tears. It often include abnormal position, stenosis or astresia of puncta, stenosis and choke from puncta to nasolacrimal canals. Or dysfunction of lacrimal ducts, etc. All these will lead t The higher incidence is in the elderly and often present as watering in the wind. And symptoms will be aggravated in cold climates, even often sweep regardless of four seasons in one year, indoor or outdoor.

Snow blindness: it is also known as snow light ophthalmia. It arises mainly because the strong ultraviolet rays in sunlight are reflected to the eye cornea by large area of snow which leads to corneal trauma. Studies ray ban have shown that 300 microns ultraviolet radiations of the sun shine on the snow field and are reflected to the eyes, which may lead to snow blindness. Then you'll be presented with the symptons of photophobia, lachrymation, swelling, pain, itch as well as a feeling of foreign objects in your eyes. Therefore, you’d better wear a pair of sunglasses when you go outdoors on snowy days in case that the stron

Chronic conjunctivitis: in autumn and winnter, chronic conjunctivitis is one of the major causes leading to tears. Chronic conjunctivitis has two types----Infectious one and non-infectious one. The former is inflammation caused by pathogenic microorganisms. Bacteria, viruses, chlamydia, fungi and others are likely to be pathogenic. The occurrence of non-infectious chronic conjunctivitis is related to the environment and the habits of using eyes, and its prevalence is increasing. The stimulations of sand, dust, smoke and harm gas and often staying up late, lack of sleep, tobacco addiction and eye fatigue are all the main factors that lead to chronic conjunctivitis.

Dry eyes: dry eyes ray ban sunglasses can lead to flowing tears for elderly. The dry and cold winter is the peak season of dry eyes. The dry eyes will make people's basic tear have less secretion, and the eyes are painful and dry. If the eye's surface is damaged, the eyes will be large quantities of reflex tears. Menopausal women, allergic rhinoconjunctivitis patients, those who had ever injuried by trachoma and those patients who have scar tissue on cornea, are all easy to cause tearing caused by dry eye syndrome. Nasolacrimal duct blockage: many elderly often flowing tears is due to nasolacrimal duct blockage. The opening of nasolacrimal duct is near the lower eyelids of nose, and the export is in the nasal cavity.