“Dacryo” is a combining form from the Greek word “dakryon,” meaning “tear.” It refers to anything related to tears, the lacrimal glands, or the tear drainage system. Tears are a complex fluid of water, oil, mucus, enzymes, and electrolytes. They are essential for eye health and clear vision, lubricating the eye’s surface, protecting it from foreign particles and infections, and nourishing the cornea.
Understanding the Tear System
The human tear system continuously produces and drains tears to keep the eyes moist and protected. Tear production begins in the lacrimal glands, located above the outer corner of each eye. These glands generate the watery component of tears. As a person blinks, tears spread across the eye’s surface, forming a thin tear film. This film also incorporates oil from meibomian glands along the eyelids, which prevents rapid evaporation, and mucus from the conjunctiva, which helps tears adhere to the eye’s surface.
After lubricating the eye, tears drain through a specific pathway. They collect at the inner corner of the eye and enter tiny openings called puncta, located on the upper and lower eyelids. From the puncta, tears travel through small channels called canaliculi into the lacrimal sac, a reservoir near the nose. Finally, tears flow from the lacrimal sac down the nasolacrimal duct, or tear duct, emptying into the back of the nasal cavity. This explains why crying can lead to a runny nose.
Common Tear Drainage Issues
Problems with the tear drainage system can lead to an overflow of tears, known as epiphora. Blocked tear ducts are a frequent cause, preventing tears from draining normally and causing them to spill onto the cheek. In infants, congenital nasolacrimal duct obstruction (NLDO) is common, often due to a thin membrane that has not fully opened, and typically resolves on its own within the first year of life.
In adults, blocked tear ducts can result from age-related narrowing of the puncta, chronic infections, inflammation, injury, or tumors. When tears cannot drain, they become stagnant, creating a breeding ground for bacteria, viruses, and fungi. This stagnation can lead to dacryocystitis, an infection of the lacrimal sac.
Symptoms of dacryocystitis include pain, redness, and swelling in the inner corner of the eye, often with watery eyes and discharge. Acute dacryocystitis can appear suddenly with severe symptoms like fever, while chronic dacryocystitis involves persistent watery eyes and recurring mild discomfort.
Tear Production Problems
Problems with tear production or quality can affect eye comfort and health. The most common condition is dry eye syndrome, occurring when eyes do not produce enough tears or tears evaporate too quickly. This disrupts the tear film, leading to symptoms like a burning, stinging, or gritty sensation, redness, and sometimes blurred vision. Dry eye can result from decreased tear production (aqueous deficient dry eye), where the lacrimal glands do not generate sufficient watery tears, or increased tear evaporation (evaporative dry eye), often due to meibomian gland dysfunction.
Factors contributing to dry eye include aging, hormonal changes (especially in post-menopausal women), environmental conditions like wind or smoke, prolonged screen time, and certain medications. Medical conditions like Sjögren’s syndrome, rheumatoid arthritis, and thyroid disorders can also cause dry eyes. Dry eyes can sometimes lead to excessive tearing, as the irritated eye produces tears to compensate, though these may lack the necessary quality to properly lubricate the eye.
Excessive tearing, or epiphora, can also occur without a drainage blockage, due to overproduction of tears in response to irritation. This can be triggered by allergies, eye infections, foreign objects, or an ingrown eyelash. Eyelid abnormalities, such as eyelids turning inward (entropion) or outward (ectropion), can also lead to watery eyes by preventing proper tear distribution or drainage.
Identifying and Treating Tear Conditions
Diagnosing tear-related conditions involves a comprehensive eye examination and specialized tests. These may include assessing tear production, tear film stability, and drainage pathways. Specific diagnostic procedures include a slit lamp exam to inspect the eye’s surface, a Schirmer’s test to measure tear production, a tear breakup time (TBUT) test, and dye disappearance tests to identify blockages.
Treatment approaches vary depending on the specific condition and its cause. For dry eyes, management often begins with over-the-counter artificial tears or warm compresses. Prescription eye drops, such as those containing cyclosporine, may be used to reduce inflammation and increase tear production. In some cases, tiny silicone plugs, called punctal plugs, can be inserted into the tear ducts to slow tear drainage.
For blocked tear ducts, gentle massage of the tear sac may help open the obstruction, particularly in infants. In adults, treatments range from warm compresses and antibiotics for infections like dacryocystitis to medical procedures. Procedures can include dilation and probing to widen narrowed ducts, or surgical interventions like dacryocystorhinostomy (DCR). DCR creates a new pathway for tears to drain from the lacrimal sac directly into the nasal cavity, bypassing the blockage, sometimes involving temporary silicone tube placement.