If the eye produces tears properly and the "pipe" that drains the tears from the eye into the nose becomes non-functioning, the tears will back up and spill over the eyelids and cause tears to run down the face. If one has a plugged up "tear pipe," not only will tears spill over the eyelids and run down the face, but the stagnant tears within the system can also become infected.
An infection within the "tear pipe" can cause a painful swelling in the inner corner of the eyelids. Surgical elimination of the obstruction is necessary to eliminate the tearing and infection that can result from such a blockage. This is known as Dacryocystorhinostomy.
Children are frequently born with an obstruction within the "tear pipe." When this occurs, tearing results. The stagnant tears within the "tear pipe" often become infected causing pus (heavy matter) to collect between the eyelids. Such obstructions may dissolve on their own within the first few months of life. If not, the ophthalmic reconstructive surgeon can eliminate this problem with refined surgical techniques.
Occasionally, the "tear pipe" obstruction will be beyond repair. When this happens, it is necessary to surgically implant an artificial "tear pipe" behind the inner corner of your eyelids to drain the tears into your nose.