Nasolacrimal Duct Obstruction
In order for the eye to stay healthy, it must remain moist. The lacrimal gland, a specialized structure about the size of an almond, located under the outer one-third of the upper eyelid, produces tears for the eyes. Each time you blink, your eyelids spread tears over the surface of the eye and pump tears into ducts in both the upper and lower eyelids. These ducts then drain those tears into your nose. This is why your nose “runs” when you cry.
Tear duct surgery is necessary when a person’s tear duct is obstructed. This can occur after an infection, broken nose, injuries, chronic sinus problems, and a variety of other causes. The two main problems that result are:
In most cases, if the smaller parts of the tear ducts and tear sac have not been damaged, a procedure can be done using the person’s own tear drainage system and anatomy to establish a new drainage point into the nose so that the tears will flow normally again. This procedure is called a dacryocystorhinostomy (DCR). In a DCR, a small silicone tube (Crawford tube) is placed in the tear ducts as a stent to help them stay open during healing. This tube is left in for 1-3 months depending on the findings at surgery. This tube is easily removed in the office without anesthesia.
If the tear duct system cannot be used, an artificial tear drain called a Jones tube is used. It is secured in place with a suture and is intended to be permanent. This tube is a small Pyrex glass tube that is surgically implanted behind the eyelids in the corner of the affected eye. It allows tears to drain out of the eye and into the nose. This procedure is called a conjunctivodacryocystorhinostomy (CDCR).
Most patients are back to their normal routine within 1 to 2 weeks.
Residual tearing is also normal during the post-operative phase while the Crawford tube or Pyrex tube is in place. While the Crawford tube acts to hold the new passageway open while you are healing, it is also acting as an obstruction to your new drainage system. Pyrex tubes may obstruct with mucus or blood during the healing process. This can be cleared with in-office irrigation.
If tearing is persistent after the Crawford tube has been removed, an additional lacrimal surgery may be required. Approximately 5% of all patients who undergo DCR or CDCR surgery require an additional lacrimal procedure due to aggressive wound healing that causes the new lacrimal passageway to close as a result of scar tissue formation. In cases where repeat lacrimal surgery is necessary, a special medication called Mitomycin may be used to diminish aggressive wound healing.