The anatomy of the common canaliculus
N. A. Tucker, S. M. Tucker and J. V. Linberg
Department of Ophthalmology, McGill University, Montreal, Quebec.
BACKGROUND: The functional valve between the common canaliculus and the
lacrimal sac has traditionally been attributed to the valve of Rosenmuller,
although this anatomical structure has never been rigorously documented.
OBJECTIVE: To define the anatomy of the canaliculus-sac junction. METHODS:
Twelve rigid plastic casts of the lacrimal outflow systems were obtained in
human cadaver specimens using a well-known biologic casting material
(partially polkymerized monomer to which a catalyst and promoter were
added). RESULTS: A consistent pattern of angulation within the canalicular
system was documented. The canaliculi bend posteriorly behind the medial
canthal tendon, then anteriorly to enter the sac at an acute mean angle of
58 degrees to the lateral wall of the sac. CONCLUSIONS: This consistent
configuration at the canaliculus-sac junction has not been previously
described and may contribute to the 1-way valve phenomenon seen in some
lacrimal disorders.
