What are the causes of excessive tearing?
There are three main causes of excessive tearing:
- Allergic or microbial reactions (conjunctivitis), reflex tearing due to irritation in dry eye conditions, redness, and discharge.
- Looseness in the eyelids, or conditions where the eyelids turn inward or outward.
- Narrowing or blockage at any part of the tear drainage system.
How is the cause of excessive tearing determined?
During a routine eye examination, the ophthalmologist uses a biomicroscope to examine the eye and detect allergies and infections. In cases of reflex tearing caused by dryness, the amount of tear production can be measured with a test strip (Schirmer test) placed inside the eyelid. If excessive tearing is due to conjunctivitis or reflex tearing, the symptoms generally improve with prescribed medication. However, in cases of narrowing or blockage of the tear drainage system, the issue is mechanical, and medications will not help. In such cases, surgery is often required to resolve the condition.
What is the anatomy of the tear drainage system?
The tear drainage system begins at tiny holes (puncta) located inside both eyelids, roughly the size of a pinhead, and extends to the lower part of the nose, where it opens into the nasal cavity. The reason why the nose runs when crying is due to this connection between the eyes and the nose. The puncta continue as small channels, about 1 cm in length, called canaliculi, which join together to form the common canaliculus. The common canaliculus leads to the tear sac. From there, the tear sac continues through the main tear duct and opens into the nasal cavity.
What is the cause and treatment of excessive tearing in babies?
Excessive tearing is a common issue during infancy, typically caused by a membrane at the lower end of the tear duct called the Hasner valve failing to open. It usually manifests as excessive tearing and crusting around the eyes 1-2 months after birth. The condition can affect one or both eyes. Since tear production typically begins after the second month of birth, excessive tearing may not be visible in the first few weeks. In the mornings, the baby may have stuck eyelids and crusting.
Treatment typically involves monitoring until the baby turns one year old. During this time, any eye infections are treated. The crusts are softened and cleaned with warm boiled water, and the eyes are washed with baby shampoo and antibiotic drops. As the tear duct may open on its own over time, monitoring without intervention is usually sufficient until the baby is one year old. If the duct has not opened by the age of 3 months, massage is applied. The massage is repeated 15-20 times in the morning and evening, using gentle pressure at the base of the nose near the tear sac to try to break the obstruction. If the duct does not open by age one, a procedure called probing is performed under anesthesia, where a probe is inserted into the tear duct to break the membrane. The procedure takes around 5 minutes, is painless and bloodless, and requires no stitches. The patient uses drops for a week post-procedure. The success rate for probing is high before age 3, but it decreases with age. If the first probing is unsuccessful, a second procedure may be performed after 2 months, and if that still fails, a tube may be inserted for 3-6 months before removal. Probing is not effective after the age of 5, so surgery (DSR) is typically required for cases that do not respond to repeated probing or tube placement.
How are tear duct blockages treated in adults?
Tear duct blockages are a common condition in adults, especially in women (who are six times more likely to experience it than men). Blockages or narrowing in any part of the tear drainage system can cause excessive tearing and/or inflammatory discharge.
The beginning of the tear drainage system is called the punctum, which is a tiny hole on the inner side of both the upper and lower eyelids. These holes can sometimes fail to form at birth but are more commonly narrowed in older age. If a patient develops tearing without crusting, the puncta should be carefully examined. Treatment of punctal narrowing is simple and effective. A perforated plaque can be placed in the narrowed punctum to restore tear flow, or the "tree snap" technique can be used to widen the punctum, both of which have successful results. This intervention is performed as an outpatient procedure, takes 5 minutes, and requires no bandaging or restrictions on daily activities.
The second part of the tear drainage system is the canaliculus, which leads from the puncta to the tear sac. If narrowing or complete blockage occurs in this area, it typically only causes excessive tearing without crusting or inflammatory discharge. If the blockage is limited to this area and the main tear duct is open, inserting a tube into the canaliculi can suffice as treatment. The tube is removed after 3-6 months.
Most tear duct blockages are located in the main tear duct. These patients experience excessive tearing, crusting, pain, redness, and purulent discharge. Occasionally, acute infections may also occur, leading to pain, swelling, and redness at the nasal root, requiring oral antibiotics. Treatment for these blockages is surgical. The surgery involves creating an opening between the tear sac and the nasal cavity. There are three methods for performing this surgery, known as DSR:
- The open method, where a 1 cm incision is made at the nasal root to access the tear duct.
- The endoscopic method, where the surgery is performed through the nose.
- The laser method, where the procedure is done via the punctum.
Among these methods, the open external DSR is the most frequently used and has the highest success rate (almost 100%). Its main disadvantage is that it may leave a scar, although experienced surgeons minimize this risk. The surgery typically takes about 30 minutes and can be performed under local or general anesthesia. A nasal tamponade may be applied for 2 days to prevent bleeding after surgery. If there is no accompanying punctal or canalicular narrowing, no tube is necessary.
The other two methods, endoscopic and laser DSR, have the advantages of no scarring, shorter surgery time, faster recovery, and lower bleeding risk, but their success rates are lower than the open method, and they often require the placement of a tube. Early successful surgery for tear duct blockages is important because treating recurrent blockages is more challenging, with a lower success rate and a higher likelihood of requiring tube placement. It is essential that tubes are not used unless necessary, as sometimes the silicon tube itself may cause a reaction leading to blockage. Regardless of the method used, the goal of DSR surgery is the same: to create an opening between the tear sac and the nasal cavity by removing a small bone that separates them. This bone is about 1 cm long and does not cause facial deformities. After surgery, swelling and bruising around the eyes may occur, and oral and topical antibiotics are used for one week. Stitches are removed after one week.