Eponymous "valves" of the nasolacrimal drainage apparatus. I. A historical review.

The nasolacrimal drainage apparatus (NDA) is of interest to anatomists, radiologists, and ophthalmologists alike, owing to its intricate luminal contour, complex surrounding structural morphology, and its clinical relevance. Here, we review the history of anatomical descriptions of so-called luminal "valves" of the NDA, including the numerous historical figures whose eponyms adorn the NDA. By 1908, multiple false "valves" that are likely no more than mounds of mucosa along the NDA had been recorded. In the modern era, these have all been largely considered speculative in nature and function aside from the consistently described true valve of Hasner (plica lacrimalis). Back then, eight so-called "valves" were believed to be identifiable. These were the "valves" of Foltz, Bochdalek, Rosenmüller, Huschke, Aubaret, Béraud or Krause, Taillefer, and Hasner or Cruveilhier or Bianchi. With the advent of detailed characterization through modern high-resolution imaging techniques, such as digital subtraction dacryocystography (DS-DCG), many of these valvular folds have come into question owing to their inconsistent identification. This historical review should be useful for greater understanding and accurate contextual interpretation of "valves" encountered on DS-DCG studies, and in clinical management and therapeutic planning of patients prior to undergoing luminal procedures on the NDA. Clin. Anat., 2018.