Digital subtraction macrodacryocystography. A new method of lacrimal system imaging.

A series of patients with obstructive epiphora was evaluated by a new method of dacryocystography. The technique involved intubation and injection of radiopaque contrast material into each lacrimal system under the control of direct sequential digitally subtracted (realtime) imaging. Simultaneous rapid sequence digital subtraction macrodacryocystography yields instantaneous high resolution magnified bone-free radiographs of the lacrimal drainage system.