In the upper portion of the orbit in each eye, are located a pair of almond shaped lacrimal glands. Lacrimal glands are responsible for secreting the tear film for the eyes. This tear film protects the delicate surface of the eye from allergens. While sneezing or crying, the tears are secreted in the lacrimal sacs that flow through the lacrimal ducts, wash the eyes and drain into nasolacrimal duct in the nasal cavity. However, when there is a plugging in the lacrimal duct, the tear film flows out of the eyelids and, the blockage results in tears becoming stagnant in the duct. This causes infection in the lacrimal drainage system. The condition is known as epiphora, excessive tearing.
Causes of Lacrimal sac tearing
- The most common cause that leads to excessive tearing is complete blockage in the nasolacrimal duct that leads to reduced drainage of the tears. The blockage is because of a malign or a benign growth in the lacrimal drainage system.
- Allergic rhinitis is a condition associated with allergic symptoms that affect the nose and the throat. Plant pollens, foods that trigger allergies and dust can cause itching in the nose and throat thereby leading to excessively watering eyes. Puffiness below the eyelids indicates the tearing in the lacrimal sac. Allergic conjunctivitis can cause excessive tearing too. When allergens like mold spores, animal dander and pollen settle on the inside of the eyelids, the membrane covering the eyeball, known as conjunctiva responds with the secretion of histamine, which is an auto response by the body’s immune system.
- Another cause that leads to tearing are abnormally placed eye lashes. One such condition is Trichiasis in which the eye lashes tend to grow inward touching the cornea and the conjunctiva. Auto immune disorders, birth defects, infection or injuries to the eyelids can cause trichiasis. This can lead to excessive tearing in the lacrimal sac too. Abnormally structured eyelids that are either placed more inward (entropian) or, more towards outward (ectropian) lead to excessive tearing in the lacrimal sac, too.
- Other causes leading to excessive tearing in the eye are associated with corneal disorders such as corneal ulcers, keratitis (inflamed cornea), glaucoma and uveitis (inflammation in the uvea).
- Infections in the lacrimal sac can lead to excessive tearing in the lacrimal sac. Dacryocystitis is a condition caused by the bacteria, Staphylococcus aureus, that leads to redness, irritation and burning sensation in the eyes. Swollen eyelids are obvious symptoms of dacryocystitis. Infection in the mucous membranes of the lacrimal drainage system can cause excessive tearing in the lacrimal sac. The infection can spread in the connective tissue fibres and the blood vessels around the lacrimal ducts leading to inflammation in the ducts and, constricting them.
- In newborns, blocked lacrimal ducts are caused by absence of puncta, orifices in the upper and eyelids. Other causes include narrow lacrimal ducts, infection and obstruction caused by the nasal bone in the lacrimal duct. Many a time, these blockages clear out within the first year of their lives.
- A complete obstruction in the lacrimal pathway can lead to stenosis in children. The underlying causes are linked to congenital anomalies like aplasia (absence of an organ at birth), lacrimal fistulae (a birth defect that is caused by an epithelial layer of the tract that connects the skin to the canaliculus and the lacrimal sac), atresia (a genetic disorder in the eye) and Hasner’s membrane. Joseph Hasner was an acclaimed Austrian ophthalmologist who was the first to discover a congenital birth defect plica lacrimalis that was caused by folding of the mucous membrane in the lower opening of the nasolacrimal duct. Therefore, the anomalous fold is known as Hasner’s valve or Hasner’s membrane.
Once the causes have been evaluated, the eyelids, the puncta, conjunctiva and the cornea are thoroughly inspected for any cascading effects of the infection. A tear pumping mechanism is engaged to test the blinking ability of the eyes. A dye test is included in the lacrimal probing to investigate the possibility of obstruction in the nasolacrimal duct. Indirect imaging procedures such as CT and MRI are engaged to investigate benign or malign growth in the lacrimal drainage system. Direct techniques such as lacrimal endoscopy and rhinoscopy are included as a part of the diagnostic probing to commence with the treatment procedure.
If a patient experiences recurring episodes of excessive tearing for a prolonged period of time, immediate medical attention must be sought. Oculoplastic surgeons like Dr. Debraj Shome have worked extensively in the field of oculoplastic orbital surgeries. These surgeries have relieved patients of the constant discomfort in the eyes caused by dryness or excessive watering. Dr. Debraj Shome is currently the Head of Plastic Surgery Departments at many hospitals in India. He is an acclaimed oculoplastic surgeon in India, whose extensive research on retinoblastoma treatment and oculoplastic surgeries, have earned him accolades.