The surface of the eye must remain lubricated and moist to stay healthy. There is a constant production of a small amount of tear by tear glands. Each time you blink the eyelid spreads the tears over the eye surface. A very small volume of tears evaporates and the rest is pumped into tear ducts and drains into the nose.
Watery eye is a common condition that can affect one or both eyes. Watery eye can be due to too much tear secretion (such as in blepharitis or hay fever) or because of a blockage in the tear drainage system. Watery eyes can cause blurred vision and irritation of the skin around the eye. When there is blockage of tear drainage system the tear sac may become infected. Watery eyes may be worse outdoors and in windy or air-conditioned environments. It may be a cause of social embarrassment or prevent people from wearing eyelid make-up.
Do watery eyes always need surgery?
No! Treatment depends on the cause and a large number of cases can be treated medically. If watery eye is due to excess tearing, surgery is usually not required. Excessive watering because of ingrowing lashes, ectropion or entropion may need surgery. When there is blockage along the tear drainage system surgery is the only effective treatment.
What can happen when a tear duct is blocked?
Blocked tear duct causes watery eyes and may result in mucus build up in the inner corner of the eye and within the tear sac. If this gets infected a painful swelling will appear which needs treatment with antibiotic tablets before surgical treatment for blocked tear duct. Main causes of obstruction include infection, previous injury or surgery to the inner corner of eyelids or nose and chronic sinusitis.
What is the surgical treatment of blocked tear duct?
The type of surgery depends on the level of blockage. Narrowing of the very beginning of the tear drainage system (punctum-see diagram), which is located on the eyelid margin in the inner corner, requires a small operation under local anaesthetics. This procedure is called punctoplasty.
Blockage of the tear duct often is further along the tear drainage system and requires an operation called DacryoCystoRhinostomy (DCR)
How is DCR performed?
This operation is usually performed under general anaesthetics but there is no need for overnight stay in hospital. DCR can be performed either through the nostril using an endoscope or externally where a small skin incision (approximately 12 mm or ½ inch) is made at the side of the nose to obtain access to the tear sac. The small scar usually heals very well and it will not be visible after a few weeks. The success rate of external DCR (access through the skin) tends to be slightly higher.
During DCR surgery a small amount of bone is removed from the side of the nose to create a bony window through which the tear sac is connected to the lining of the nose. A fine plastic tube is inserted in the new bypass to protect the delicate opening in the drainage system and prevent failure of surgery due to natural scaring. This tube is usually removed after a few weeks in the clinic. If the obstruction is in the canaliculi (see diagram) a small glass tube, called Jones tube, is inserted behind the eyelid to drain tears. This is intended to be a permanent drain and will not be removed.
The success rate of external DCR is very good at approximately 95% where the procedure is performed for treatment of complete obstruction located below the tear sac. In cases where there is partial obstruction the success rate is lower at approximately 60%.
What are the risks of DCR surgery?
The major risk of this operation is nosebleed. Certain medications including Aspirin should be stopped 2 weeks prior to surgery to reduce the risk of excessive bleeding during the operation. You need to discuss your medication with your surgeon at the time of consultation.
Any bleeding is controlled during the operation but in the first 10-12 days following surgery while the wound inside the nose is healing there is a small risk (less that 1 in 100) of nosebleed which requires packing of the nose in the hospital.
Like any surgery there is also small risk of infection and scar formation.