Overview
To keep your eyes moist, a small amount of tears are produced by the lacrimal gland and drained by the nasolacrimal duct. ‘Nasolacrimal duct’ is the medical term for your tear duct, which starts with two tiny channels in your eyelids that join together in a sac located under the skin in an area between your eye and nose (called the lacrimal sac), and then continue downwards into your nasal cavity.
Sometimes the duct can become narrow (known as nasolacrimal duct stenosis) or blocked (nasolacrimal duct obstruction), leading to an overflow of tears (a condition called epiphora). This condition may be present from birth or could be caused by external factors, such as an inflammation, autoimmune diseases, stones formation, cancer, or in cases of complications after nasal or turbinate surgery.
Symptoms
The most common symptom of nasolacrimal duct system obstruction is the aforementioned uncontrolled tears overflow (epiphora). Other symptoms of nasolacrimal duct system obstruction are pain, swelling, redness, or pus discharge.
Diagnosis
Your doctor may diagnose a blockage in the nasolacrimal duct by giving you some drops of an eyewash and checking whether or not you taste/feel the eyewash in your throat. To confirm the diagnosis, an imaging technique called dacryocystography, which is an out-patient procedure, can be performed. Other imaging techniques are the CT and MRI dacryocystography. Depending on the imaging method used, your doctor may also be able to see the cause of the stenosis or obstruction, its location, and its severity.
Treatment
Two possible routes of treatment for nasolacrimal duct stenosis are surgery and minimally invasive techniques. Both types of treatment are performed as out-patient procedures, under local anaesthesia. If you choose to undergo surgery, this means you will have a dacryocystorhinostomy, a surgical procedure in which the surgeon creates a new communication line between the lacrimal sac and the nasal cavity.
On the other hand, interventional radiology gives you the possibility to have a minimally invasive procedure. One interventional radiology technique is to use a tiny balloon to expand the area (known as balloon dilation), which may be accompanied by a tiny mesh metal tube (called a stent) being used to support the structure of the duct and to keep it open. In this procedure, an interventional radiologist inserts a catheter into the affected tear duct, using X-rays for guidance. The interventional radiologist then passes a guidewire and a tiny balloon into the duct and then, once the balloon is dilated, the area is gently expanded.