Endoscopic Lacrimal Duct Surgery in Ophthalmology: Treatment of Lacrimal Duct Obstructions—The Range of Treatments Offered to Patients at the Clinic

Tears protect the eye from drying out and facilitate blinking by improving lubrication. Tears are produced in the lacrimal gland, located on the side above the eye socket. Several gland openings release the fluid onto the cornea. Each blink spreads the fluid across the surface of the eye.

In the lower part of the eye, tears first collect toward the center and then drain away through the lacrimal puncta. These are located at the inner corner of the eye on the upper and lower eyelids. They serve as the entrances to the tear ducts. Even people without medical training can easily recognize them by their dark spots.

The drainage channels carry the tear fluid further into the nasolacrimal duct. From there, it drains completely through the nose.

Lacrimal gland (a) and lacrimal pathways: b = upper lacrimal punctum. c = upper lacrimal duct. d = lacrimal sac. e = lower lacrimal punctum. f = lower lacrimal duct. g = nasolacrimal duct

The main symptom of impaired tear drainage is a persistently watery and overflowing eye (epiphora). Tear fluid flows out of the eye, causing the person affected to see their surroundings blurrily. People with this condition feel particularly limited when reading or driving, as if they were “looking through an aquarium.”

Other symptoms include:

• Conjunctivitis
• Inflammation of the lacrimal sac
• Inflammation of the tear ducts
• Pus formation

The mucus discharge is often mistaken for conjunctivitis, but is actually caused by a blocked tear duct @ 

Over time, the lower eyelid may become lax due to constant “eye rubbing” and “wiping away tears.” This results in the lacrimal punctum shifting away from the eye, accompanied by outward turning of the eyelid (ectropion of the eyelid with eversion of the lacrimal punctum).

The lacrimal punctum then does not lie close enough to the eye to collect the tear fluid. Tightening of the lower eyelid is necessary to allow for tear drainage.

Drainage disorders of the eye can have various causes.

In some cases, there is no open passage within the lacrimal duct from birth. Doctors can open these small blockages using endoscopic lacrimal duct surgery.

Inflammation of the eye can also cause the delicate structures to adhere to one another. Severe inflammation can additionally lead to adhesions within the tear ducts.

Some patients are prone to the formation of stones within the tear ducts. These tear stones prevent the normal drainage of tears. Endoscopic lacrimal duct surgery can also help in this situation.

For endoscopic lacrimal duct surgery to be successful, the anatomical conditions of the nose and the lacrimal drainage system must be suitable.

The doctor decides whether endoscopic lacrimal duct surgery is appropriate following an ophthalmological examination.

In doing so, the doctor must rule out certain conditions that are not suitable for endoscopic lacrimal duct surgery, such as hypersecretion.

In cases of hypersecretion, the drainage system functions correctly, but the lacrimal gland produces too much tear fluid.

A narrowing of the drainage passage due to a malposition of an eyelid

The examination includes an inspection of:

• Eyelids
• Lacrimal puncta
• Conjunctiva and
• cornea

A functional test using dyes can also be informative.

Often, a tear duct irrigation test provides information about the exact location of the narrowing or blockage.

Using indirect imaging techniques (ultrasound, X-ray) and contrast agents, the doctor assesses the patient’s tear drainage.

Direct imaging techniques are useful when the problem is located in the nasal area. A nasal endoscopy, for example, reveals whether tear drainage in the nasal area is normal.

Endoscopic examination of the tear ducts (dacryoendoscopy) is considered a major advance in medicine. This procedure allows the doctor to view the tear ducts from the inside.

This method has been available since the 1990s. Shortly after the introduction of endoscopic examination in the 1990s, endoscopic lacrimal duct surgery was added.

Lacrimal endoscopy provides a direct and highly magnified view of pathological changes in the mucous membrane of the tear ducts.

This enables the doctor to detect whether there is inflammation, polyps, lacrimal sac stones, or other pathological changes that impair tear drainage.

In rare cases, the surgery cannot be performed endoscopically via the lacrimal ducts. The accessibility of the lacrimal ducts and the bony structure of the nose are the primary factors in such cases.

In such cases, more extensive surgical procedures may be necessary.

Endoscopic lacrimal duct surgery is not applicable for drainage disorders caused by facial skull fractures.

These conditions require a more extensive surgical procedure.

Endoscopic lacrimal duct surgery is also insufficient in cases of extensive scarring caused by a herpes infection.

In cases of severely inflamed tissue (dacryocystitis), the small structures of the lacrimal drainage system are swollen. Therefore, endoscopic lacrimal duct surgery is also not appropriate in these cases.

To prevent the spread of infection, antibiotic therapy is recommended prior to endoscopic lacrimal duct surgery. Doctors also do not perform endoscopic lacrimal duct surgery in cases of mucoceles (accumulation of mucus in a cavity).

Before the procedure, the doctor obtains a detailed picture of the condition of the surgical site. This enables the doctor to plan the procedure optimally.

The procedure is performed under general anesthesia. 

The goals of endoscopic lacrimal duct surgery are:

• Removal of punctate stenoses 
• Restoration of the drainage channel in the existing lacrimal drainage system

Enlarging the lacrimal punctum with a probe makes it easier to introduce a flushing solution. The flushing solution prevents bleeding.

Even the smallest injuries to the mucous membrane can lead to bleeding, which causes the mucous membrane to stick together or form adhesions within the lacrimal canal system.

The irrigation solution also prevents major bleeding within the tear duct, which can occur when the optical instrument is inserted.

Often, irrigation alone is sufficient to resolve the lacrimal duct stenosis. By slowly withdrawing the optical instrument and carefully irrigating, the monitor displays a clear image of the lacrimal duct.

If the surgeon is unable to widen the narrowing, he advances a small laser or miniature drill toward the narrow point.

To keep the tear duct system open, the surgeon inserts small silicone probes at the end of the endoscopic tear duct surgery. These remain in the duct for 3 to 6 months. Their purpose is to protect the tear duct from scar tissue formation and keep it open.

One surgical technique used in endoscopic lacrimal duct surgery is laser dacryoplasty (LDP; surgery to restore the tear duct).

The tried-and-true instrument is the diode laser. It has a wavelength of 980 nm and a power output of 7 to 9 watts. The laser can often clear localized blockages.

Another method of endoscopic lacrimal duct surgery involves the use of a miniature drill (microdrillplasty, MDP). The miniature drill has a diameter of 0.3 mm and rotates at 600 revolutions per minute. This makes it possible to widen the narrowing.

The miniature drill is used in the following cases:

• Opening of narrowings
• Removal of mucosal folds, membranes, and polyps
• Crushing of lacrimal duct stones

Complications and risks are rare in endoscopic lacrimal duct surgery. However, complications are possible.

The following side effects may occur:

• Bleeding
• Swelling
• Bruising

Injuries to the eyelids or cornea are very rare. The procedure almost always leads to an improvement in symptoms.

You must also take into account the complications associated with general anesthesia.

As with all surgeries performed under anesthesia, you must not drive a car or operate heavy machinery after endoscopic lacrimal duct surgery.

Taking pain medication also impairs your reaction time. If you notice any abnormalities or concerning complications, you should see a doctor immediately.

After lacrimal duct surgery, you should not blow your nose. This would put too much strain on the surgical site and could cause the silicone probes to slip out. Instead, you should only gently dab your nose.

To prevent bleeding and post-operative bleeding, avoid physical exertion and extreme heat.

The silicone probes typically remain in the body for 3 to 6 months. After that, your doctor will remove them completely. In some cases, they may remain in the lacrimal system for up to a year.

The treatment of a lacrimal duct stenosis through endoscopic lacrimal duct surgery is often successful. In many patients, tears can drain freely again afterward without causing any symptoms. In some patients, at least the symptoms improve.

However, after several years, the tear ducts may become blocked or obstructed again.

Non-surgical measures may be used prior to endoscopic lacrimal duct surgery. 

These include:

• Irrigation
• Eye drops
• Medications 

However, these usually do not help resolve a stenosis and are used solely to treat inflammation.

If endoscopic lacrimal duct surgery does not produce the desired results, further surgical procedures may be performed afterward. These include, for example, external lacrimal duct surgery (Toti procedure).

It is important that you have the lacrimal duct surgery performed at a center that specializes in this procedure.