In order to be sure that a patient’s watery eye symptoms are indeed due to blocked tear ducts, the ophthalmologist will carry out a diagnosis using a technique known as lacrimal irrigation, which includes the following steps:
 

• Topical anesthetic is administered to the patient’s eye.
• The doctor dilates the puncta. 
• Irrigation (flushing sterile liquid through the duct and into the nose) is then carried out to ensure the duct is open and that any blockage has been removed. 

In cases where the patient’s lacrimal system is functioning normally, the sterile fluid will pass freely through to the nose. The patient will have a salty or bitter taste in the back of their throat. If, however, the patient’s tear duct is restricted or blocked, the liquid will be unable to drain down freely or may flow slower than normal, and there will be regurgitation of the liquid through the punctum. 
 
This method, in addition to confirming the cause of the condition, can also help to determine the location of the blockage, indicating whether the blockage is in the nasolacrimal duct, the puncta, or the lacrimal sac. It can also help to identify the degree of the blockage as well.  
 
After endoscopic DCR surgery (which should take approximately 45 minutes to 1 hour), the patient is recommended to stay in the hospital overnight in order to sleep off the effects of the anesthesia. Some patients may experience a slight swelling or bruising and may feel as if they have a cold for about 3-5 days. Doctors will usually prescribe antibiotic medication to be taken for approximately one week following surgery, along with eye drops and nasal spray to help cleanse the eyes and nose. They can be self-administered at home and are required to be used for about one month following surgery. An eye patch is not required for the patient to wear at home.