[Magnetic resonance sialography. A new diagnostic method for imaging salivary duct patency].

The new technique of non-invasive magnetic resonance (MR) sialography was evaluated for normal and various pathologic conditions of the parotid gland. Ten volunteers and 15 patients with various symptomatic diseases of the parotid gland were tested in the present study. Diseases included pleomorphic adenoma, cystadenolymphoma, carcinoma ex pleomorphic adenoma, ductal carcinoma, adenoid cystic carcinoma, lymphoepithelial carcinoma, non-Hodgkin's lymphoma, sialolithiasis, sialadenitis, Heerfordt's syndrome and congenital duct ectasies. In addition to the usually performed T1 and T2 cross-sectional sequences a heavily weighted T2 sequence (TR 3600, TE 800) was performed and allowed depiction of a fluid-filled parotid duct. Results showed that the main parotid and primary branching ducts were depicted reliably in all normal cases and all patients, except one with sicca syndrome. Pathological conditions such as duct dilatations, duct strictures, obstructing duct calculus and irregular shapes and courses of the ductal system were demonstrable. While X-ray sialography obtained a higher resolution, only MR sialography was able to depict dilated ducts proximal from a complete obstruction, as well as all ductal cysts. Our findings show that MR sialography can be applied successfully to investigations of the parotid gland system. There have been no contraindications or complications to date because MR sialography is non-invasive. The technique will also allow the salivary ducts and lesions to be differentiated from the course of the facial nerve.