The canthus is the notch at each edge of the eye, where the two eyelids meet. The inner, or medial, canthus is called the nasal canthus, because of its proximity to the nasal structures. The outer, or lateral, canthus is called the temporal canthus because of its proximity to the temporal region of the skull. The nasal canthus features the fleshy, pink lachrymal caruncle and the canaliculi which lead into the lachrymal sac. Research Canthus