Kevin C. Welch, MD
Epiphora, or excessive tearing, is defined as the overflow of tears from one or both eyes. Epiphora can occur continuously (be present all the time), or it can occur intermittently (be present only sometimes). Epiphora is subdivided into two main categories: overproduction of tears or inadequate drainage of tears. In this article, we will be discussing inadequate drainage as a cause of epiphora.
The lacrimal apparatus (the part of your body that creates tears and transmits them to the nose) is a complex system of ducts and sacs that begins at the outer corner of your eyes in the lacrimal gland. This is the gland that produces tears. Tears then wash across the surface of the eye from the outer to inner corner, protecting, moistening and cleaning the outer layer of the eye. The upper and lower eyelids each contain a single opening near the nasal bridge. These openings are slightly raised on mounds called puncta. Each punctum drains tears into a tubular structure called the canaliculus. There is an upper (superior) and lower (inferior) canaliculus. Each of these small tubes brings the tears toward the nose until both tubes join to form one tube, the common canaliculus. Within the common canaliculus are tears from the superior and inferior canaliculus. The common canaliculus delivers tears to the lacrimal sac, which rests underneath the inner corner of the eye near the nose. The lacrimal duct, a tubular structure leading into the nose itself, drains tears from the lacrimal sac. Tears enter the nasal cavity through an opening near the bottom of the nasal cavity
known as Hasner's valve.
It is in the area from the lacrimal sac through the nasolacrimal duct where obstruction can occur.
Nasolacrimal duct obstruction is classified as primary or acquired. Primary nasolacrimal duct obstruction is the result of an unknown cause and results in either functional or physical obstruction of the drainage pathway. In acquired nasolacrimal duct obstruction, blockage can be caused by infection, inflammatory disorders, trauma (e.g., facial fractures), or surgery (e.g., sinus surgery, head and neck cancer surgery).
Primary nasolacrimal duct obstruction typically occurs in middle-aged individuals. There are various proposed causes, some of which include changes in hormone levels and osteoporosis.
Many forms of bacteria and other microorganisms can cause infection and inflammation of the nasolacrimal duct and lacrimal apparatus. When infection and inflammation occur, scarring may result, and this can either narrow or completely block the nasolacrimal duct.
Autoimmune diseases, such as vasculitis, can cause severe inflammation of the nasolacrimal duct, and this also can result in narrowing or obstruction (blockage) of the nasolacrimal duct even in the absence of infection.
Facial trauma can cause disruption of the lacrimal apparatus by either causing scarring within the system or by cutting or tearing the nasolacrimal duct. Injury to the puncta and canaliculi can occur during facial surgery to correct facial trauma deformities as well.
Lastly, injury to the nasolacrimal duct can occur during various endoscopic sinus surgery
procedures. Many times this is recognized at the time of surgery and can be repaired by performing a DCR
Patients typically present with a primary complaint of too much tearing. Most frequently, this tearing is clear in nature. However, some patients complain of too much mucus discharge from the eye as well. Some patients report periodic infection of the region between the eye and the nose; this is known as dacryocystitis.
It is important to tell your physician if you have recently undergone surgery, such as sinus surgery, or have had recent trauma to your face, as these are most likely to be the causes. Recent colds
or sinus infections
are also important.Your physician should also know if you are using any eye medications or have any other body-wide symptoms if there are no easy-to-explain circumstances leading up to the drainage.
An examination of the eyes in patients who have epiphora (excessive tearing) most often reveals either overflow of tears down the cheek or an excessive build up of tears along the lower lid. In patients who have dacryocystitis, the region between the eye and the nose can be tender, and pressure exerted on this area often reveals the flow of pus or mucus into the eye.
A number of studies may be performed by your rhinologist to understand the nature of the obstruction. A thin strip containing fluorescein (a fluorescent dye) can be placed at the corner of the eye. When this orange filter paper mixes with tears, it turns bright green. After a few minutes, it should be observable in the nasal cavity with nasal endoscopy or by blowing your nose on to tissue paper. If it is not, your doctor may try to gently open the puncta and inject saline or fluorescein-stained saline into the lacrimal system to see if it enters the nasal cavity. Lastly, an x-ray, otherwise known as a dacryocystogram, may be performed to determine where the obstruction is located.
The treatment of epiphora due to nasolacrimal duct obstruction
is discussed in the surgery section of the Patient Education Website.
Epiphora due to nasolacrimal duct obstruction can be a significant problem for patients. If you have excessive tearing, a simple procedure known as a DCR
may permanently relieve your problem with tearing. You can discuss your situation with a rhinologist to determine if you are a candidate for this simple procedure.