Abstract

Lacrimal scintigraphy (LS) was performed in 860 lacrimal drainage systems (LDS) in 188 patients with bilateral epiphora and 226 patients with unilateral epiphora. A very high incidence of canalicular obstruction was found in these patients, the incidence being higher in the group with unilateral epiphora. It is suggested that a canalicular block is a commoner cause of obstructive epiphora than has been recognised previously and that LS is a reliable method of studying the canalicular function. A significant number (42%) of the opposite asymptomatic eyes of patients with unilateral epiphora were found to have an abnormality in the LDS, which supports the view that abnormalities in the LDS tend to be bilateral. Only 25% of these asymptomatic systems showed a normal drainage, confirming that physiological obstruction can exist below the lacrimal sac in normal lacrimal drainage systems.