Lacrimal dilation and irrigation is a well-tolerated procedure that helps diagnose and treat nasolacrimal duct obstruction. Nasolacrimal duct obstruction is a blockage found in any one of the parts of the tear drainage system; these are the punctum, ampulla, canaliculi, and lacrimal sac. This obstruction causes excess backflow of tears known as epiphora.
Some symptoms of epiphora include:
- Excessive tearing
- Pus or mucus discharge from the lids
- Recurrent eye infection
- Painful swelling in the eye's corner
- Blurred vision
- Inflammation of the sclera
Some causes of nasolacrimal duct obstruction include:
- Congenital - About 5% of newborns have nasolacrimal duct obstruction, but 90% of these cases resolve within the first year of life. It could be caused by the disappearing of the valve of Hasner, an infection, underdevelopment of the tear duct, and a narrow tear duct system.
- Trauma to the eye
- Prior surgery
- Obstructive fibrosis
Lacrimal dilation helps to open up the punctum, which are two small holes found in the corner of both eyelids where tears drain from the eye. When the procedure is done, it improves the flow of tears through the nasolacrimal ducts, also known as the tear ducts.
Before the Procedure
The surgeon will give the patient specific eating and drinking instructions as this is age-specific. The patient can take their medicine as usual. However, they are required to notify the surgeon about it. On the morning of the procedure, the patient will be asked to go into the specialist's office without any nail polish or jewelry.
Once at the specialist's office, the doctor will go through the anesthesia options that best suit the patient. If the patient is a child, s/he will be put under general anesthesia while adults will be put under local anesthesia. Before the surgery begins, the patient or the child's guardian will be required to sign a consent form.
After the procedure, the patient may be tired until the effects of the anesthesia wear off. Therefore, they will require someone to take care of them for a few hours.
The surgeon begins by applying a topical anesthetic to the punctum with a cotton-tip applicator and resting it for about a minute. This anesthetic also helps to eliminate a blink reflex. The surgeon will ask the patient to look up and away from the site.
S/he can choose to use a slit-lamp during the procedure. An advantage of using the slit-lamp is that it offers magnification to assess the punctum accurately and better determine where to insert the dilator and cannula. An advantage of not using one is that the patient has free movement and the surgeon has easy access to the patient's lid. If the patient has an unusual tear duct anatomy, the use of a slit lamp is recommended.
If the surgeon opts not to use the slit-lamp, the patient will be requested to lay down to have their head reclined. However, in this position, the saline solution may cause a gag reflex.
Next, the surgeon pulls the lid and inserts the lacrimal dilator about 2mm vertically into the punctum. The surgeon starts with the thin side of the dilator and switches to the bigger side once the punctum is fully dilated.
Once inserted, the surgeon rolls the dilator in a circular manner. As s/he keeps rotating the dilator, s/he re-orients the dilator to 90 degrees horizontally while still keeping it in the punctum. The surgeon knows that the punctum is sufficiently dilated, once the cannula fits.
S/he then removes the dilator and inserts a cannula attached to a saline-filled syringe. The cannula is also inserted vertically then re-oriented horizontally, just like the dilator. The surgeon takes great care not to go too far as it will reach the nasal bone, causing the patient some discomfort.
Here, the surgeon slowly depresses the syringe's plunger to release the saline solution into the lacrimal system. S/he will then ask the patient to inform them if they can taste the saline solution.
If the patient immediately tastes the saline solution, it implies that the nasolacrimal system is open.
If the surgeon feels a resistance of the plunger or experiences regurgitation of the saline, s/he could try to remove the blockage by irrigating multiple times to move it further down the lacrimal drainage system. If successful, the patient will be able to taste the saline.
This procedure should take 10 minutes to complete.
Risks & Complications
Some irritation may be felt when dilating or inserting the cannula. However, this should be well tolerated.
During the procedure, there is a possibility of trauma to the lacrimal drainage system. Over time, this could result in canalicular or nasolacrimal duct obstruction.
Some postoperative risks include pain, swelling, and infection. These often go away on their own or are easily treatable.
Aftercare & Recovery
The patient will receive antibiotic/steroid drops to use for one week postoperatively. The patient shouldn't experience any pain after the procedure. Therefore, there is no need for any painkillers.
There are no general lifestyle or dietary restrictions after the procedure.
In case the surgeon is unable to remove the obstruction using this procedure, the patient will have to undergo lacrimal probing.