MR imaging of parotid tumors. Identification of the facial nerve

Using 0.5 T-MRI, 12 cases of parotid tumor and 2 cases of no tumor were evaluated to identify the intraparotid facial nerve. On 8 tumor sides and 12 normal sides of these cases, the images were taken, using volume imaging with SPGR method and the reference line drawn between the inferior margin of the medulla of the atlas and the superior margin of the medulla of the mandible. Facial nerve was identified in 7 of 8 tumor sides and 9 of 12 normal sides, and the findings were confirmed in 3 operated cases. On 7 cases (14 sides) using different conditions, facial nerve was not identified. The usefulness of MRI for preoperative examination of parotid tumor was discussed. (author)