ABSTRACT
ETIOLOGY A dacryocele is formed when the nasolacrimal duct is obstructed at both the proximal and terminal ends, both at the valve of Rosenmuller (at the level of the common canaliculus entering into the nasolacrimal sac) and the valve of Hasner (at the level of the nasolacrimal duct entering the inferior meatus in the nose). Blockage of both the inlet and the outlet of the duct leads to sequestration of mucus which can become secondarily infected.
