Tear fluid protects the eye from drying out and facilitates blinking by improving the lubrication function. Tear fluid is produced in the lacrimal gland at the side above the eye socket. Several gland openings release the fluid onto the cornea of the eye. Each blink distributes the fluid on the surface of the eye.
In the lower area, the tears first collect towards the center and then drain off in the area of the lacrimal puncta. These are located in the inner corner of the eye on the upper and lower eyelid. They represent the entrances to the tear ducts. The dark dots mean that even laypeople can easily recognize them.
The draining tear ducts drain the tear fluid further into the nasolacrimal duct. From there it drains completely via the nose.
Lacrimal gland (a) and tear ducts: b = upper lacrimal punctum. c = upper lacrimal tube. d = lacrimal sac. e = lower lacrimal punctum. f = lower lacrimal tube. g = nasolacrimal duct
The main symptom of impaired tear drainage is a permanently watery and overflowing eye (epiphora). The fluid in the eye runs out of the eye and the person affected has a blurred perception of their surroundings. Especially when reading and driving, those affected feel severely restricted, similar to "looking through an aquarium".
Other symptoms include
The mucus secretions are often interpreted as conjunctivitis, but are due to the tear drainage disorder @ The lower eyelid may become slack over time due to the constant "drying of the eye" and "wiping away tears". This results in a displacement of the lacrimal punctum away from the eye.
The lacrimal punctum is then not close enough to the eye to absorb the tear fluid. Tightening of the lower eyelid is necessary to allow tear drainage.
Teardrainage disorders in the eye can have various causes.
In some cases , there is no permeable connection within the tear duct from birth. Doctors can open these punctiform occlusions with the help of endoscopic lacrimal duct surgery.
Inflammation of the eye can also clog the fine structures. Severe inflammation can also lead to adhesions within the tear ducts.
Some sufferers tend to form stones within the tear ducts. These tear stones prevent the physiological drainage of tears. Endoscopic lacrimal duct surgery can also help with these findings.
For endoscopic lacrimal duct surgery to be successful, the anatomical conditions of the nose and the draining lacrimal duct system must be right.
The doctor decides whether endoscopic lacrimal duct surgery is appropriate after an ophthalmologic examination.
He or she must rule out certain diseases that are not suitable for endoscopic lacrimal duct surgery, such as hypersecretion.
In hypersecretion, the outflow functions correctly, but the lacrimal gland produces too much tear fluid.
A narrowing of the outflow due to the misalignment of an eyelid
The examination includes an inspection of the:
- Eyelids
- Lacrimal puncta
- conjunctiva and
- cornea
A functional test with dyes can also be informative.
A lacrimal duct irrigation often provides information about the exact location of the constriction or blockage.
The doctor uses indirect imaging procedures (ultrasound examination, X-ray examination) and contrast media to assess the patient's drainage conditions.
Direct imaging procedures are useful if the problem is in the area of the nose. A rhinoscopy, for example, provides information on whether the drainage of tears in the nose area is in order.
Endoscopic assessment of the tear ducts (dacryo-endoscopy) is considered a major advance in medicine. This 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.
Tear duct endoscopy enables direct and highly magnified visualization of pathological changes in the tear duct mucosa.
This allows the doctor to recognize whether there are inflammations, polyps, lacrimal sac stones or other pathological changes that impair the outflow of tears.
In rare cases, surgery cannot be performed endoscopically via the lacrimal ducts. The accessibility of the tear ducts and the bony situation of the nose play a role here.
Larger surgical steps may then be necessary.
Endoscopic lacrimal duct surgery cannot be used for drainage disorders caused by a facial skull fracture.
More extensive surgery is required for these disorders.
Endoscopic lacrimal duct surgery is also not sufficient for larger scarring caused by a herpes infection.
In the case of severely inflamed tissue (lacrimal sac inflammation), the small structures of the lacrimal drainage system are swollen. Endoscopic lacrimal duct surgery is therefore also not appropriate in this case.
To prevent the spread of germs, antibiotic therapy is advisable before endoscopic lacrimal duct surgery. Doctors also do not perform endoscopic lacrimal duct surgery on mucoceles (accumulation of mucus in a cavity).
Before the procedure, the doctor obtains a precise picture of the condition of the surgical area. This enables him to plan the course of the procedure optimally.
The procedure is performed under general anesthesia.
The aims of endoscopic lacrimal duct surgery are
- Removal of punctiform stenoses
- Restoration of the drainage channel in the existing lacrimal drainage system
Dilation of the eye puncta with the help of a probe makes it easier to introduce an irrigation solution. The irrigation solution prevents bleeding.
The smallest injuries to the mucous membrane lead to bleeding, which causes the mucous membrane to stick together again or grow together within the tear duct system.
The rinsing solution also prevents major bleeding within the tear duct, which can occur when the optical instrument is inserted.
Irrigation is often sufficient to correct the tear duct stenosis. By slowly withdrawing the optical instrument and careful irrigation, the monitor transmits a clear image of the tear duct.
If the surgeon is unable to widen the narrowing, he advances a small laser or miniature drill to the narrowing point.
To keep the tear duct system open, he inserts small silicone probes at the end of the endoscopic tear duct operation. These remain in the canal for 3 to 6 months. Their purpose is to protect the tear duct from re-scarring and to keep it open.
One surgical procedure for endoscopic lacrimal duct surgery is laser dacryoplasty (LDP/plasty to restore the lacrimal duct).
The proven instrument is the diode laser. It has a wavelength of 980 nm and an output of 7 to 9 watts. The laser can often dissolve punctiform blockages .
Another method of endoscopic lacrimal duct surgery is the use of a miniature drill (microdrill plastic, MDP). The miniature drill has a diameter of 0.3 mm. It achieves 600 revolutions/minute. This makes it possible to widen the narrow point.
The miniature drill is used in the following cases:
- Opening of constrictions
- Removal of mucosal folds, membranes and polyps
- Crushing of tear duct stones
Complications and risks rarely occur during endoscopic lacrimal duct surgery. However, complications are possible.
The following side effects may occur:
Injuries to the eyelids or cornea occurvery rarely. The procedure almost always leads to an improvement in symptoms.
The complications of general anesthesia must also be taken into account.
As with all operations under anesthesia, you must not drive a car or use heavy machinery after endoscopic lacrimal duct surgery.
Taking painkillers also impairs your ability to react. If any abnormalities or worrying complications occur, you should consult a doctor immediately.
You should not blow your nose after lacrimal duct surgery. This would put too much strain on the surgical area and could cause the silicone probes to slip out. Instead, you should only dab your nose.
To prevent bleeding and secondary bleeding, avoid physical exertion and intense heat.
The silicone probes usually remain in the body for 3 to 6 months. Your doctor will then remove them completely. In some cases, they may remain in the lacrimal duct system for up to a year.
The removal of lacrimal duct stenosis through endoscopic lacrimal duct surgery is often successful. In many patients, the outflow of tear fluid is subsequently possible again without symptoms. In some patients, the symptoms at least improve.
However, years later, the tear ducts may become overgrown or blocked again.
Non-surgical measures can be usedbefore endoscopic lacrimal duct surgery.
These include
- Irrigation
- eye drops
- medication
However, these usually do not help to dissolve a stenosis and only serve to treat inflammation.
If endoscopic lacrimal duct surgery does not have the desired effect, further surgical measures can be carried out afterwards. These include, for example, external lacrimal duct surgery (Toti surgery).
It is important that you have the lacrimal duct surgery performed at a specialized center.
