Technical report: digital subtraction dacryocystography.

Twenty-one patients presenting clinically with obstructive epiphora were investigated by digital subtraction dacryocystography (DSDCG). This technique is quick and simple to perform, with good patient acceptance. It produces diagnostic images on a single radiographic projection. The proximal lacrimal apparatus is well demonstrated. Patient radiation dose to the orbit is apparently reduced in DSDCG without the use of lead eye shields. The technique of DSDCG was readily acquired by junior radiologists. Reliable and accurate demonstrations of lacrimal duct obstructions were produced in a general radiological department where dacryocystography is an occasional examination. We advocate the use of digital techniques in dacryocystography when the equipment is available.