lacrimal sac is drained by the nasolacrimal duct, which runs through the skull and empties through the nasal puncta, located on the ventral floor of the nasal passage
When your horse have a blocked tear duct, or a nasolacrimal duct obstruction, his tears can't drain normally, leaving him with a watery, irritated eye. Blocked tear ducts are caused by a partial or complete obstruction in the tear drainage system. This condition is almost always is correctable.
The usual first step is to flush the duct. Restrain your horse properly, likely sedate , then pass a thin flexible tube(I use 18G to 20G Branula tube) partway up the duct from the nostril end. A saline solution is then flushed through and may be followed with steroids or antibiotics if the case warrants them.
