Digital subtraction dacrocystography

Abstract

The method of digital subtraction is based on the ability to eliminate interfering shadows from the X-ray picture, which makes it possible to make the parts of the picture containing contrast substance more visible. Digital subtraction dacryocystography makes better and more detailed imaging of the lacrimal pathways possible, in particular in the proximal part of the efferent lacrimal pathways, as compared with conventional dacryocystography. This is important for more detailed assessment of the necessary surgical intervention on the lacrimal pathways and its prognosis. The advantage is the possibility to deposit the image in the memory of the instrument as well as its digital processing and the smaller radiation load to which the lens is exposed. The authors examined by the method of digital subtraction dacryocystography 25 patients with disorders of the efferent lacrimal system and present some normal and pathological findings of the lacrimal pathways.