Dacryocystography is a fluoroscopic contrast examination of the nasolacrimal apparatus. The duct is cannulated enabling iodinated contrast to be instilled into the nasolacrimal system.
The most frequent indication is epiphora: excessive tearing or watering of the eyes.
Equipment is similar to that used to perform a sialogram.
One suggested technique:
- patient in the supine position
- similar projection to an OM view in most cases
- acquisition of a preliminary control film to confirm patient positioning and exposure
- dilate the punctum to insert the cannula
- non-ionic iodinated contrast injection into a cannulated duct, avoiding air bubbles
- acquire images, whilst ask the patient to look straight ahead to avoid blinking
- a post-removal of cannula erect view may be useful in diagnosing functional blocks
CT dacryocystography has also been described 1.