A DCR is an operation on the tear ducts to help improve drainage of tears from the eye to the nose. It is usually performed when there is a blockage in the main tear duct between the eye and the nose (the nasolacrimal duct), that has caused the eye to water and sometimes become infected. It is also sometimes performed when there is a partial blockage to improve tear drainage. A DCR operation effectively makes a new passage for the tears to pass from the eye to the nose. This new passage or bypass joins the upper part of the main tear duct (the tear sac) to the inside of the nose after removing a small area of bone that lies between the tear sac and the inside of the nose. The lining of the tear sac is carefully stitched to the lining of the nose to create a new tear passage after this bone is removed.
At the end of the operation, a thin piece of soft silicone plastic tubing is passed through the tear ducts and the new passage into the nose, tied with a knot inside the nose and left there usually for several weeks. This tubing is just visible at the inner corner of the eye where it passes between the upper and lower tear duct openings. Its purpose is to protect the lining of the new tear passage while it is healing. It is removed painlessly through the nostril after several weeks.