Blocked tear ducts are caused by a partial or complete obstruction in the tear drainage system. The drainage system, which begins at the inside corner of your eye, normally carries tears away from the surface of your eye into your nose where they are reabsorbed or evaporate. When you have a blocked tear duct, your tears can't drain normally, leaving you with a watery, irritated eye.

As many as 20 percent of newborn babies have a blocked tear duct at birth, but it usually clears up on its own in the first year of life. Adults can get a blocked tear duct as a result of an infection, inflammation, an injury or a tumor. A blocked tear duct almost always is correctable, but the treatment depends on the cause and your age.

The main symptom of a blocked tear duct is excessive tearing or watery eyes. Because blocked tear ducts often cause eye infections, other symptoms may include:

• Recurrent eye inflammation (conjuctivitis)
• Recurrent eye infections (dacrocystitis)
• Painful swelling of the inside corner of the eye
• Eye mucous discharge
• Blurred vision
• Bloody tears

When to see a doctor
If your eye has been watery and leaking or is continually irritated or infected, make an appointment to see your doctor. Some blocked tear ducts are caused by tumors pressing on the tear drainage system, and quick identification of the tumor will give you more treatment options.

Most of your tears originate from your lacrimal glands, which are located above each eye. The tears cascade down the surface of your eye to lubricate and protect it, and then drain into tiny holes in the corners of your upper and lower eyelids, called puncta. The tears then travel through the small canals in the lids (canaliculi) to where the lids are attached to the side of the nose (lacrimal sac), then down the nasolacrimal duct before emptying into your nose, where they evaporate or are reabsorbed. A blockage can occur at any point in the tear drainage system, from the puncta to your nose. When that happens, your tears don't drain properly, giving you watery eyes and increasing your risk of developing eye infections and inflammation.

Blocked tear ducts can be present at birth (congenital) or can occur at any other age. Causes include:

• Congenital blockage at birth. As many as 20 percent of all newborns have a blocked tear duct. In these instances, the tear drainage system may not be fully developed or there may be a duct abnormality. A thin tissue membrane often remains over the opening that empties into the nose (nasolacrimal duct) in congenitally blocked tear ducts. This usually opens spontaneously during the first or second month of life.
• Abnormal development of the skull and face (craniofacial abnormalities). The presence of craniofacial abnormalities, including certain disorders such as Down syndrome, increases the likelihood of blockage of the tear ducts.
• Age-related eye changes. Older adults may experience eye and eyelid changes that can cause blocked tear ducts.
• Eye infections or inflammation. Chronic infections and inflammation of your eyes, tear drainage system or nose can cause your tear ducts to become blocked.
• Facial injuries or trauma. An injury to your face can cause bone damage near the drainage system and disrupt the normal flow of tears through the ducts.
• Tumors. Nasal, sinus or lacrimal sac tumors can occur along the duct system, blocking it as they grow larger.
• Cysts or stones. Sometimes, cysts and stones form in the tear duct system, creating blockages.
• Topical medications. Rarely, long-term use of certain topical medications, such as those that treat glaucoma, can cause a blocked tear duct.
• Other medications. A blocked tear duct is a possible side effect of docetaxel (Taxotere), a commonly used chemotherapy medication for breast or lung cancer.

Certain factors increase your risk of developing a blocked tear duct:

• Age and sex. Older women are at highest risk of developing blocked tear duct due to age-related eye changes.
• Chronic eye inflammation. If your eyes are continually irritated, red and inflamed (conjunctivitis), you're at higher risk of developing a blocked tear duct.
• Previous surgery. Previous eye, eyelid, nasal or sinus surgery may have caused some scarring of the duct system, later resulting in a blocked tear duct.
• Glaucoma. Anti-glaucoma medications are often used topically on the eye. If you've used these or other topical eye medications, you're at higher risk of developing a blocked tear duct.
• Previous cancer treatment. If you've had radiation or chemotherapy to treat cancer, particularly if the radiation was focused on your face or head, you're at higher risk of developing a blocked tear duct.

Because your tears aren't draining the way they should, the tears that remain in the duct system become stagnant, promoting growth of bacteria, viruses and fungi. These organisms lead to recurrent eye infections and inflammation. Any part of the tear duct system, including the clear membrane over your eye surface (conjunctiva), can become infected or inflamed because of a blocked tear duct.

At your appointment, your doctor will gather a history of your eye symptoms and ask questions related to the causes of blocked tear ducts, as well as other conditions that can cause watery, irritated eyes. When you go to see your doctor, be prepared to discuss the following:

• Your symptoms, how long they've lasted and if anything relieves them
• Any previous eye or eyelid surgery
• Any previous facial trauma, injuries or surgery
• Any facial nerve conditions
• Any previous radiation

Be prepared for an eye exam and a few tests to see how your tears are draining. Your doctor will also examine the inside of your nose to determine if any structural disorders of your nasal passages are causing an obstruction. If a blocked tear duct is suspected, other tests may be performed to find the location of the blockage in order to choose the best treatment.

Some of the tests used to diagnose a blocked tear duct include:

• Fluorescein dye disappearance test. To test how your tears are draining, one drop of a special dye is placed in each eye. If there's a significant amount of dye in your eye after five minutes of normal blinking, you may have a blocked tear duct.
• Irrigation and probing. Your doctor may flush a saline solution through your tear duct system to check how it's draining, or use a slender instrument (probe) inserted through the tiny drainage holes at the corner of your eye (puncta) to check for blockages.
• Dacryocystography or dacryoscintigraphy. In these procedures, a contrast dye is passed from your puncta in the corner of your eye through your tear drainage system. Then, X-ray, computerized tomography (CT) or magnetic resonance imaging (MRI) images are taken to find the location and cause of the blockage.

The cause of your blocked tear duct will determine which treatment is right for you. Sometimes, more than one treatment or procedure is needed before a blocked tear duct is completely corrected.

If a tumor is causing your blocked tear duct, treatment will focus on the cause of the tumor. Surgery may be performed to remove the tumor, or your doctor may recommend using other treatments to shrink it.

Treatment options for non-tumor-blocked tear ducts vary from simple observation to surgery.

Conservative treatment
A high percentage of infants with congenital blocked tear duct improve on their own in the first several months of life, after the drainage system matures or the extra membrane involving the nasolacrimal duct opens up.

If the blocked tear duct isn't opening on its own, your doctor may recommend that you use a special massage technique to help open up the membrane covering the lower opening into your baby's nose. While pressing on the puncta on the inside of your baby's eye to prevent tears from coming back into the eye, stroke downward firmly on the inside of your baby's nose. This forces tears down the tear duct system, and could be enough pressure to break through the leftover membrane. Some parents report hearing a popping noise as the membrane breaks. The massage can be used two to four times a day, along with antibiotic drops to prevent infection.

Conservative treatment may be recommended if the tear ducts become blocked from tissue swelling after facial injury. In most cases of blocked tear ducts after such facial trauma, the drainage system starts functioning again on its own a few months after the injury, and no further treatment is needed. Your doctor may recommend waiting three to six months after your injury before considering the need for surgical intervention to open a blocked tear duct.

Minimally invasive treatment
Minimally invasive treatment options are used for infants and toddlers whose blocked tear ducts aren't opening on their own, or for adults who have a partially blocked duct or a partial narrowing (stenosis) of the puncta.

• Dilation, probing and irrigation. This technique works to open congenital blocked tear ducts in most infants. The procedure can be done using general anesthesia, or using a restraint in very young babies. First, the doctor enlarges the puncta openings with a special dilation instrument, and then a thin probe is inserted through the puncta and into the tear duct system. The doctor threads the probe all the way out through the nasal opening, sometimes causing a popping noise as the probe pierces through the extra membrane. The probe is removed, and the tear duct system is flushed with a saline solution to clear out any remaining blockage. This treatment successfully clears blocked tear ducts in many infants less than 1 year of age.

  For adults with partially narrowed puncta, a similar procedure is done in your doctor's office. The tear ducts are flushed and irrigated while the puncta are dilated. Antibiotics may be prescribed for any infections. If irrigation and dilation doesn't work, surgery may be necessary to open narrowed puncta. Sometimes, a small incision at the punctal opening may be all that's necessary.

• Balloon catheter dilation. This procedure opens tear drainage passages that are narrowed or blocked by scarring, inflammation and other acquired conditions. While you're under general anesthesia, a tube (catheter) with a deflated balloon on the tip is threaded through the lower nasolacrimal duct in your nose. The doctor then uses a pump to inflate and deflate the balloon a few times, sometimes moving it to different locations along the duct system. This procedure is more effective for infants and toddlers, but also is sometimes used in adults with partial blockage.
• Stenting or intubation. In this procedure, tiny silicone or polyurethane tubes are used to open up blockages and narrowing within the tear duct system. The procedure, which is done under general anesthesia, involves having a thin tube threaded through one or both puncta in the corner of your eye, all the way through the tear duct system and out through your nose. After the insertion, a small loop of tubing remains visible at the corner of your eye, but it's not usually bothersome. These tubes are generally left in for three to six months, then removed. Possible complications include inflammation from the presence of the tube.

Surgery
Surgery is still the most effective treatment for adults and older children with acquired blocked tear ducts. It's also highly successful in infants and toddlers with congenital blocked tear ducts, though it's typically used after other treatments have been tried.

The surgery used to treat most cases of blocked tear ducts (called dacryocystorhinostomy) reconstructs the passageway for tears to drain out through your nose normally again. First, you're given general anesthesia, or local anesthesia if it's performed as an outpatient procedure. The surgeon accesses your tear drainage system, then creates a new, direct connection between your lacrimal sac and your nose. This new route bypasses the duct that empties into your nose (nasolacrimal duct), which is the most common site of blockage. Stents or intubation typically are placed in the new route while it heals, and then removed three to six months after surgery.

The steps in this procedure vary, depending on the exact location and extent of your blockage, as well as your surgeon's expertise:

• External. An external dacryocystorhinostomy is still the most commonly used and highly successful surgical method of opening a blocked tear duct. Under general anesthesia, your surgeon makes an incision on the side of your nose, near where the lacrimal sac is located. After connecting the lacrimal sac to your nasal cavity and placing a stent in the new passageway, the surgeon closes up the incision with a few stitches.
• Endoscopic or endonasal. The same bypass procedure can be performed using endoscopic instruments. Instead of making an incision, the surgeon uses a microscopic camera and other tiny instruments inserted through the nasal opening to your duct system. Sometimes, a fiber-optic light is inserted into your puncta to illuminate the surgical area. The benefits of this method are that there's no incision and no scar, and the recovery typically is faster and easier. The drawbacks are that it requires a surgeon with special training, and the success rates aren't as high as with the external procedure.
• Bypassing the entire lacrimal duct system. Depending on the type of blockage, your surgeon may recommend a reconstruction of your entire tear drainage system (called conjunctivodacryocystorhinostomy). Instead of creating a new channel from the lacrimal sac to your nose, the surgeon will create a new route from the inside corner of your eyes (puncta) to your nose, bypassing the tear drainage system altogether.

Following surgery for a blocked tear duct, you'll use a nasal decongestant spray, as well as topical eyedrops to prevent infection and reduce postoperative inflammation. You'll continue these medications two to three times a day for two to three weeks following the procedure. After three to six months, you'll return for removal of any stents used to keep the new channel open while it healed.

There's no way to prevent a congenital blocked tear duct. To reduce your risk of developing a blocked tear duct, be sure you get prompt treatment of eye inflammation or infections. And to avoid eye infections in the first place:

• Avoid having contact with children and adults who have pink eye (conjunctivitis).
• Wash your hands thoroughly and often.
• Try not to rub your eyes.
• Replace your eyeliner and mascara regularly, and never share these cosmetics with others.
• If you wear contact lenses, keep your contact lenses clean according to recommendations provided by the manufacturer and your eye care specialist.