Tear Overflow in Small Kids
It is very common for infants and older kids to present with a blocked nasolacrimal duct.
What Exactly is a Blocked Nasolacrimal Duct?
A normal eye continuously produces secretions from the lacrimal glands, which are located on the outer upper side of each eye.
These secretions wash the outer surface of cornea on a continuous basis and also keep the eye moist.
The tears then drain down via small channels (canaliculi), on the inner side of the eye into tear sacs on each side. From there, they drain into the nasolacrimal duct which connects the tear sac to the upper back portion of the nose.
Causes of Tear Overflow in Babies
The nasolacrimal duct may be blocked by tissue debris or by a thin transparent membrane which acts like a curtain obliterating its path.
Incomplete development of the duct. Sometimes, the duct may take longer to develop, maturation at the age of 1 year after birth.
Symptoms With Which a Baby Presents
- Tear overflow
- Frequent eye infections due to stagnant tears in the tear gland (dacryocystitis).
Management
For most of the cases, all you need to do is to gently massage the inner upper bony part of the nose. This puts pressure over the tear gland, pressing it so that the nasolacrimal duct drains away. Also any debris present in it gets flushed.
This may take a few months, so it is advisable to wait for 1 year of age before attempting something invasive.
Cases Where the Duct Is Not Fully Developed
Wait for at least 1 year of age, giving time to the duct to construct by itself.
Meanwhile, the eye should be kept clean. Wash off any excess tear from it on a regular basis.
If the problem does not resolve by itself, some test need to be done to know the exact problem. Is the nasolacrimal duct blocked, or is it incomplete in some way. Sometimes, the duct is anatomically incorrect, its passage is tortuous or kinked (structural disorders).
Diagnostic Tests
Tear drainage test (fluorescein dye disappearance test)– One drop of dye in put in each eye and its drainage along the pathway is assessed.
Probing– A slender probe is inserted through the tiny holes at the inner corners of the eye. It is gently passed to see if any obstruction is present.
Probing may also dilate the tiny holes or puncta, which is the only problem in some cases. Dilatation solves the problem in these cases.
Dacryoscintigraphy (Imaging studies in the eye)– A contrast dye is passed through the puncta. X- ray or CT or MRI may be done to assess the location and cause of blockage, or any abnormality in the passage of the duct.
Invasive Procedures
Probing and irrigation– A slender probe is passed through the punctal openings present on the inner side of the eye. It is gently passed through the passage, dilating it and removing any obstruction present in it. Simultaneous irrigation may be done to clean the passage.
Probing is done under anesthesia and is not painful.
Sometimes, the passage contracts again and again and so a stent is put in the passage after probing.
Balloon catheter dilation– The nasolacrimal duct may be scarred from inside due to repeated infections and subsequent scarring. Try dilating the tube with a balloon catheter. This procedure is done under general anesthesia.
Surgery
In cases where the tube is incomplete or kinked, reconstruction of the passage is done surgically.
Alternatively, another tube is constructed parallel to the original passage, draining tears properly into the nose.
Surgery is recommended only if all other options fail.
The procedure is called dacryocystorhinostomy. It is a skilled microsurgical procedure.
It is done in cases where there are structural problems in the nasolacrimal duct. It is usually attempted after two years of age.
Approaches for the Procedure
External approach– Here, an incision is made on the side of the nose, near the location of the lacrimal sac. A piece of bone between the tear sac and the nose is removed. Then, the inner lining of the tear sac is pulled and attached to the lining of the nasal cavity for permanent patent drainage.
The surgery requires adequate local anesthesia with sedation.
Endonasal approach– The same procedure described above can be done using an endoscope inserted into the nasal cavity. No
incision is required here, however, only a surgeon with special training can attempt it.
Constructing a new external canal (Conjunctivodacryocystorhinostomy)– Instead of creating a new channel from the lacrimal sac to the nose, a new route is created from the conjunctiva, near the inside corner of the eye, to the nasal cavity. The original tear drainage system is bypassed completely.
In all the procedures described above, a delicate stent or tube is put in the newly created canal for a few weeks after surgery. This is to prevent sticking or narrowing of the new passage and preventing scarring during the healing phase.
Care After Surgery
After the surgery, nasal decongestant sprays are used to reduce post op inflammation. Antibiotics are used topically for the eye to keep infections in check.
Stent is removed after 3 to 6 months.
The results of the procedures are good. The only thing to be assessed is, if the child is big enough to handle anesthesia or not.
About the Tube
The tube is plastic (silastic), hypoallergenic and very soft in texture. Most infants accept it without any difficulty.
Using the tube is absolutely essential. If not used in time, the newly constructed canal may collapse or get scarred and subsequently narrowed. So. the success of the procedure depends greatly on the use of the stent.
