Overview of the lacrimal system
The lacrimal system is responsible for the production of tears, lubrication of the eye, and drainage of tears into the nose. Specific glands make tears, the largest of which is the lacrimal gland. These glands are located underneath both upper eyelids. After their production, tears are distributed onto the surface of the eye (cornea and conjunctiva) by the eyelids. This process is essential for the health of the eye because tears provide nutrients and prevent cell death.
Eyelids also help to “pump” the tears into the tear sac with each blink. From the sac, the tears are carried to the nose through a small conduit called the nasolacrimal duct. These tears carry away dead cells, mucus, and bacteria from the eye surface. The eyelids, therefore, wash away debris from the eye and prevent irritation of the ocular surface.
What are the symptoms of an infection of the lacrimal system, and how do you treat them?
The location of an infection, caused by a blockage in the lacrimal system, dictates the symptoms experienced by the patient. Age, gender, and clinical presentation provide the clinician with a clue as to the site of the infection.
A tear duct may become blocked in small ducts located in the eyelids, called canaliculi. This obstruction is more often seen in middle-aged women. When this happens, the cause of blockage is usually the presence of a foreign body, such as silicone plug used to treat dry eye, or a stone produced by bacteria. The small duct becomes red and inflamed, secretes purulent material, and causes acute pain and tenderness in the affected eyelid. This condition requires surgery for its treatment and does not resolve with antibiotics alone. The operation is done under local anesthesia and takes about 15 minutes. The resolution of the symptoms is immediate.
When the blockage is located in the tear sac or lower duct, i.e., nasolacrimal duct, the sac becomes infected, and an abscess may form. This is seen as a red bump on the inner angle of the eye. An abscess is extremely painful. Medical treatment consists of warm compresses, oral antibiotics, and anti-inflammatory medications. However, this only works to relieve the acute symptoms but does not solve the problem.
The permanent solution for this type of obstruction is a surgical procedure called DCR. A DCR works by creating an opening from the lacrimal sac to the nose, bypassing the obstruction. This operation is performed endoscopically, through the nasal cavity, to avoid a scar. The opening allows the tears, debris, and mucus to drain to the nose, and the patient to experience relief and the elimination of symptoms. A successful DCR significantly reduces the probability of the formation of another abscess.
A blockage in the sac or nasolacrimal duct may not cause an acute infection or abscess, but it may cause a milder infection that becomes chronic. In these cases, the patient will experience tearing in that eye and purulent secretion upon awakening. This chronic dacryocystitis is not as dangerous as its acute counterpart, but it is very bothersome for the patient. The treatment is the same, though, and requires an endoscopic DCR. In this case, the goal is to reduce the frequency of tearing and eliminate the secretion.