Lacrimal streams: the demonstration of human lacrimal fluid secretion and the lacrimal ductules.

The clinical demonstration of the ductular orifices of the human lacrimal gland is reported. Lacrimal fluid secretion can be shown after instillation of 2% sodium fluorescein. Ductular orifices are visible on biomicroscopy. In keratoconjunctivitis sicca the lacrimal fluid streams appear normal, or to be diminished or absent.