LACRIMAL ANATOMY

The tear drainage system begins with two small openings called puncta, one in the upper and one in the lower eyelid. Through these openings, the tears enter into small ducts called canaliculi, which drain them into the lacrimal sac situated between the inside corner of the eye and the nose. The lacrimal sac opens into a canal called the nasolacrimal duct that drains the tears into the nose. Blockage of the tear duct at any level (from the punctum to the nose) can result in constant or intermittent tearing (watery eyes).