What is dacryrrhea?
Dacryrrhea (or epiphora) is the overflow of tears from the eye (the medical term for an eye tear is lacrima) and is commonly called watery eyes. It is clinically defined with the presence of "tears streaming down the cheek" and is distinct from the normal phenomenon of tearing of the eyes with yawning. Tears, produced in the lacrimal glands, are normally carried away by the nasolacrimal drainage system; overproduction or obstruction of this drainage leads to dacryrrhea. Tears are produced as a reflex response to irritation or injury of the cornea, or as part of the emotional state response. This is distinguished from normal tearing, as a healthy person sheds 0.75–1.1 microliters of tears per minute.
Causes of dacryrrhea include:
* Obstruction of the lacrimal drainage system
* Overproduction of tears
* Poor apposition between the globe and eyelids
* Loss of the normal channels of spreading of tears
There are numerous causes for both increased tear production and impaired tear drainage. Common problems include:
- Nasolacrimal duct obstruction is the most common cause of dacryorrhea. This can occur due to anatomical variations, aging, inflammation or scarring from trauma, previous surgery or infection. In neonates, the cause may simply be delayed canalization.
- Allergic and infectious conjunctivitis: allergic conjunctivitis (such as hayfever and vernal keratoconjunctivitis), vernal conjunctivitis, blepharoconjunctivitis and infective conjunctivitis can all cause dacryorrhea.
- Ectropion is the turning out of the eyelid, particularly the lower eyelid. This causes tears to spill over onto the skin of the cheek rather than being passed into the lacrimal drainage system.
- Facial paralysis, such as Bell's palsy can also cause dacryorrhea.
- Blepharitis is a common cause of dacryorrhea. It affects the skin of the eyelid, making the skin red, swollen, crusty and itchy, so that the eyelid does not fit effectively on the surface of the eye. This can cause both overspill and increased production of tears.
- Dacryops, also known as canaliculitis, refers to the acute or chronic inflammation of the canaliculi. Common symptoms of dacryops includes epiphora, soreness, and swelling.
- Sjogren syndrome, a chronic autoimmune inflammation, that destroys the exocrine glands secreting sweat and tears. This means too little saliva and tears are produced, which can lead to dry eye and dacryorrhea.
- Tumours of the conjunctiva, lacrimal drainage passage or nasopharynx.
Lacrimal drainage system (LDS) obstructions can have a variety of reasons:
- Congenital anomalies in the LDS development
- Infectious causes (e.g., canaliculitis, dacryocystitis)
- Auto-immune diseases (e.g., sarcoidosis, vasculitis, Sjogren's disease)
- Trauma
- Iatrogenic causes (e.g., after refractive surgeries, endoscopic procedures)
- Neoplasia (tumours)
Dacryorrhea can be associated with an underlying systemic condition, such as autoimmune disorders, or cancer. It can be a symptom of congenital glaucoma or other eye conditions, or develop after injury to the facial nerves or the lacrimal glands.