Tear Duct Examination

 

Tests used to diagnose a blocked tear duct include:

1. Tear drainage test. This test measures how quickly your tears are draining. One drop of a special dye is placed on the surface of each eye. You may have a blocked tear duct if after five minutes most of the dye is still on the surface of your eye.
2. Irrigation and probing. Your doctor may flush a saline solution through your tear drainage system to check how well it's draining. Or he or she may insert a slender instrument (probe) through the tiny drainage holes at the corner of your lid (puncta) to check for blockages. In some cases this probing may even fix the problem.
3. Eye imaging tests. For these procedures, a contrast dye is passed from the puncta in the corner of your lid through your tear drainage system. Then X-ray, computerized tomography (CT) or magnetic resonance imaging (MRI) images are taken to find the location and cause of the blockage.