TEARING AND LACRIMAL SYSTEM (TEAR DUCT)
Tears are produced by multiple glands on the eye, eyelid margin, and the lacrimal gland. The tears maintain a film over the eye to protect it and provide nourishment. To maintain equilibrium, tears produced are continuously drained through the tear ducts. The ducts allow tears to flow from the inner corners of the eyelids out into the nose. A functional tear duct is the reason why you have to blow your nose when you cry – the tears drain into your nose and it becomes runny.
Excessive tearing is a very common problem and may be due to any of the following:
Dryness – An overproduction of tears is often reflexive tearing due to dryness and irritation of the eyes.. Treating a dry eye condition, sometimes by simply using artificial tears, will stop the reflexive tearing.
Blockage of the lacrimal drainage system – When any part of the tear drainage system is blocked or narrow, the tears well up in the eyes and flow over onto the cheek. Picture your eye as a bathtub in which the faucet is constantly running. A blockage of the tear drainage system is like to plug the drain.
Eyelid Malposition – If the mouth of the tear duct, which is located on the inner corner of the eyelid, is turned inward or outward, the tears may not find the duct and can flow over the edge of the eyelid.
If tearing is caused by reflexive tears due to dry eye, eye lubrication can help. Plugs can be placed into the opening of the tear ducts (called the punctum), to keep tears in the eyes longer and assist with lubrication.
Treatment to correct a blockage in the duct is customized depending on the location and nature of the blockage.
If tearing is caused by eyelid malposition, then eyelid repositioning can help.
If tearing is due to the narrowing of the openings of the tear duct (called the punctum or canaliculus), surgical enlargement of the punctum and placement of a silicone tube can correct the problem. The tube is placed into the duct to stretch to improve the opening and prevent recurrent closure of the punctum, allowing the tears to drain.
More commonly, tearing is due to a complete obstruction of the drainage system, called the nasolacrimal duct (a portion of tear duct located in the nose). Treatment for this problem involves surgically bypassing the blockage by creating a new opening that connects the tear drainage system to the nose.
This surgery is called dacryocystorhinostomy or DCR. Our doctor performs DCR surgery endoscopically, so there is no visible scar. Endoscopic DCR has an excellent success rate – tearing resolves in 90-95% of patients after this surgery.
Rarely, tearing is caused by a complete obstruction of the canaliculi (a portion of tear duct in the eyelid). In this case, the entire drainage system must be bypassed by a new opening. The new opening is created by surgically inserting a small glass tube called a Jones tube into the corner of the eyelid, which allows tears to drain directly into the nose.
This procedure is called a conjunctivorhinostomy (CDCR). A CDCR with the placement of a Jones tube is only performed if other surgical options are not possible.