Valvular system of the lacrimal drainage pathway and the valve of Rosenmuller

The valves of the lacrimal drainage system are an enigma with a rich eponymous history. The unidirectional flow of tears along with the ultrastructural demonstration of distinctive mucosal folds on the luminal surface has rekindled an interest in them. The first in vivo direct demonstration of the valve of Rosenmuller and its functions has laid to rest some of the controversies of its existence and that of the valve of Huschke. The dynamic assessment of the valve of Rosenmuller has shown a well-defined functional role in the fa-cilitation of unidirectional tear flow. The present mini review describes the embryological aspects, brief overview of the eponymous valves, techniques for their identification along with recent structural and functional aspects of the valve of Rosenmuller. & COPY; 2023 Elsevier GmbH. All rights reserved.