DIGITAL SUBTRACTION DACRYOCYSTOGRAPHY (DS -DCG) AND RESULTS OF ENDONASAL LACRIMAL SURGERY

103 patients with obstructive epiphora, or illacrimation, underwent en donasal lacrimal surgery (dacryocystorhinostomy in the modification of Veis-Cdlaus and canaliculorhinostomy). Postoperative complications in cluded local infections and were seen in 7 cases (6.8%). After finishi ng the treatment 90 patients (87.4%, Table 4) were free of symptoms an d remained so for years of follow-up. Recurrent stenosis developed in 13 cases (12.6%). DS-DCG provides valuable information for confirming the indication for surgery and determining the surgical procedure in o bstructive epiphora. In addition it may help to assess a successful ou tcome of the operation in the course of treatment (Fig. 7 and 8). By m eans of real time subtraction the successive opacification is visualis ed on the monitor screen during injection thus controlling the examina tion. Incomplete contrast filling and overopacification are avoided. D igitalisation may direct the extent of homogenisation of the backgroun d of the radiographic image. Anatomical structures are preserved and w eakly contrasted structures are depicted precisely and independent of the background. Stenoses before (Fig. 2 and 3), within (Fig. 4) and be hind (Fig. 6) the lacrimal sac can be differentiated from complete, in complete (Fig. 4) and functional stenoses.