Dacryocystorhinostomy (DCR) is a procedure performed for the treatment of watering eyes due to blockage of the nasolacrimal duct (NLD). Tears originate in the lacrimal gland, located at the upper outer margin of the eye. As tears cross the eye with each blink, they are directed into small openings in the eyelids called puncta. From this point, tears travel through a pathway known as the canalicular system into the lacrimal sac. The lacrimal sac is located between the eye and the nose, and funnels tears into the nasal cavity through the nasolacrimal duct (Figure 1). As this is quite a long path for tears to travel, there can be many causes of excessive tearing. Blockage of the nasolacrimal duct is one common cause, and can be treated by creating a direct opening from the lacrimal sac into the nasal cavity in a procedure known as DCR.
DCR is indicated in the treatment of tearing due to nasolacrimal duct obstruction. Blockage of this duct can be due to trauma, chronic exposure to dust or smoke, prior surgery, tumor, or inflammatory medical conditions, but most commonly occurs without an identifiable cause. To determine if this is truly the problem area in a patient with tearing, a number of tests may be performed. A physical examination is performed by the physician, and is often followed by probing and irrigation / syringing of the canalicular system.
Surgery is often performed under general anesthesia, but may be performed under local anesthesia according to patient or surgeon preference. DCR can be achieved from an external (through a facial incision) approach or from an endoscopic / endo-nasal (using a small telescope and instruments through the nose) approach. The goal of the procedure is to bypass the obstructed nasolacrimal duct and allow for tear drainage into the nose directly from the lacrimal sac with opening by cut or laser.
Overall success rates exceed 90%, although in particular cases the likelihood of success may be lower. The risks and side effects of the procedure are relatively low, and can potentially lead to a long-lasting relief of bothersome tearing.
Although there are many causes of tearing / lacrimation / watering eyes (epiphora) some patients are excellent candidates for DCR. A proper evaluation must take place to determine the likelihood of success with this surgery. Different conditions will have their own preferences in particular aspects of the procedure—external or endoscopic, use of stents, size of opening created, postoperative visit schedule—but the ultimate goals and success rates are quite similar.