Yan X, et al. - In this investigation involving 33 candidates [20 normal individuals (40 eyes), 2 individuals with chronic lacrimal canaliculitis (4 eyes), 10 patients with chronic dacryocystitis (16 eyes), and 1 patient with lacrimal punctum atresia (2 eyes)], researchers studied the microstructure of the lacrimal canaliculus and the features of lacrimal canalicular diseases by 80-MHz ultrasound biomicroscopy (UBM). According to results, the low echo of the lacrimal canalicular lumen and a high echo of the lacrimal canalicular wall were observed at 80-MHz UBM of the lacrimal canaliculi (vertical section) in normal individuals. Findings suggested that the 80-MHz UBM is a new non-invasive technique which can be used to clearly visualize the lacrimal canaliculus' fine structure, including the mucosal epithelium and subepithelial elastic fiber layer. Using this approach will enhance understanding of the lacrimal canaliculi's hierarchical structure and provide a comprehensive basis for diagnosis, differential diagnosis, and treatment plan in lacrimal passage disease patients.