Consecutive imaging of the facial nerve using high-resolution magnetic resonance imaging

This study examined the signal intensity of the facial nerve on T-1-weighte d images using the multiplanar reconstruction (MPR) method of the high-reso lution magnetic resonance imaging technique. The facial nerves of 12 sides in 6 normal adults were consecutively observed from the mastoid area to the intraparotid area. Results indicated that facial nerves showed similar or relatively high signal intensity compared with the intensity of the parotid parenchyma. Although previous studies have indicated that the intraparotid facial nerve had a low signal intensity, facial nerves were probably confu sed with the intraparotid ductal system or vessels which show low signal in tensity on T-1-weighted images or with low signal lines due to chemical art ifacts. All facial nerve trunks were clearly identified; however, 33% (4/12 ) of second branches of the nerves shifted or curved too strongly to be det ected in the parotid parenchyma with this method.