Lacrimal duct obstruction

Tears are produced by the lacrimal glands, located in the upper outer part of the eye, and have the function of cleaning and humidifying the eye for its proper functioning. In addition to the main lacrimal gland, there are accessory glands in the eyelid called Meibomian glands that are also responsible for producing a fatty secretion that forms the outermost part of the tear film. The tear leaves the gland towards the upper cul-de-sac of the eye and from there passes to the surface of the eyeball.

The tear is collected by the lacrimal points, located in the inner part of each of the eyelids (upper and lower), and from there it continues through some canaliculi to the lacrimal sac, located in the lower inner part of the eye, from where it is it drains through the nasolacrimal duct, which leads to the back of the nose. When, for whatever reason, the tear drainage system is interrupted, we speak of an obstruction of the tear ducts.

How is it produced?

Lacrimal duct obstruction is very common in, generally due to the existence of a congenital membrane that prevents proper drainage, which in 90% of cases resolve spontaneously. In some cases, newborns have a congenital obstruction of the tear ducts, a dacryostenosis. Sometimes there may be nasal polyps that obstruct the nasolacrimal canal and prevent the correct drainage of the tear.

In adults, the tear ducts can be obstructed for various reasons, such as:

• Facial paralysis that affects the orbicularis oculi muscle.
• Insufficiency of the tear drainage valve mechanism.
• Eyelid abnormalities.
• Alterations of the nostrils (deviation of the septum).
• Recurrent infections (conjunctivitis).
• Allergic rhinitis.
• Chronic inflammations of systemic origin.
• Facial trauma
• Lumps
• Presence of lithiasis in the tear ducts.

Mechanical obstruction is the most common cause of obstruction of the nasal passages, especially at the level of the nasolacrimal duct.

Symptoms

The obstruction of the tear ducts causes an accumulation of the tear, which causes a constant, copious and annoying lacrimation, which is called an epiphora. Likewise, the patient often complains of itching or discomfort in the eye, a sensation of a foreign body, redness of the eye, production of thick legaña and an inability to completely close the eye.

If a severe obstruction occurs, a bacterial superinfection can occur, with a purulent discharge through the eye, pain, signs of inflammation in the inner edge of the eye and sometimes fever.

If the lacrimal sac becomes infected, dacryocystitis occurs, in which purulent discharge is seen through the lacrimal points and redness in the inner corner of the eye, with a lumpy mass that is painful to the touch, which in severe cases can reach to create a fistula that drains into the skin. It is usually accompanied by systemic signs, such as fever and general malaise.

Dacryocystitis can also occur in children with congenital obstruction of the nasolacrimal ducts, presenting symptoms similar to that of adults. Some children are born with the lacrimal sac already inflamed, called a dacryocystocele, which is seen as a bluish bump on the lower inner corner of the eye.

Diagnosis

The diagnosis will be based on the observation of a constant lacrimation in the patient, as well as on the presence of external signs of obvious infection, such as purulent discharge, eyelid involvement or the vision of a painful swelling in the area of ​​the lacrimal sac.

If an obstruction is suspected, there are various tests that allow assessing the level of the obstruction, such as instillation of saline solution into the lower lacrimal duct and exploration of it with a cannula to see if the ophthalmologist comes across some obstacle. Seeing whether the serum refluxes or drains through the nasolacrimal ducts will allow the area of ​​obstruction to be assessed.

The Jones test is a technique that also makes it possible to follow the course of the tear ducts by instilling a dye called fluorescein.

Dacryocystography is a technique that allows the lacrimal ducts to be assessed with contrast and is indicated in cases of persistent lacrimation, after trauma or surgery, masses in the nasolacrimal area or chronic inflammatory processes in this same area.

Conventional radiology and computerized axial tomography (CT) will make it possible to observe anomalies at the level of the nasal septum and the ocular orbit, being useful especially after facial or head trauma.

Treatment

As already mentioned, 90% of congenital forms of tear duct obstruction resolve themselves, helping with regular massages in the lacrimal sac area. If not, the tear ducts can be probed under anesthesia to unclog them, with an effectiveness that is close to 95%. Dacryocystitis, both in adults and children, should be treated with local and systemic anti-inflammatory drugs and surgical drainage of the infected lacrimal sac to facilitate the discharge of pus.

When in the adult the epiphora is persistent and with the exploration of the lacrimal ducts its unblocking is not achieved, surgery should be resorted to, particularly if the lacrimation is very bothersome for the patient. The intervention will consist of making a communication between the nose and the lacrimal sac, which is known as dacryocystorhinostomy, which can be carried out externally (less frequently), or endonasally (inside the nose) assisted by laser. , with a much better postoperative period, since it does not require general anesthesia to perform it. The tear ducts can also be dilated using a balloon, called a dacryoplasty. If the epiphora is due to eyelid or nasal septum alterations, these should be surgically corrected to avoid constant lacrimation secondary to external obstruction of the lacrimal passages.

Precautionary measures

There are no specific preventive measures to avoid eyelid obstruction. In any case, it is important that in the face of constant tearing, you go to the ophthalmologist as soon as possible.

• Lacrimal duct obstruction is very common in young children and 90% of cases resolve spontaneously.
• In adults, the obstruction can be due to many causes, such as recurrent infections (conjunctivitis), alterations of the nasal passages (deviation of the septum) or facial trauma.
• The obstruction of the tear ducts causes constant and annoying tearing, as well as itching, discomfort, eye redness, production of thick frown and inability to completely close the eye.