Magnetic resonance cisternographic evaluation of glossopharyngeal, vagus, and accessory nerves.

PURPOSE

The individual visualization of the glossopharyngeal, vagus, and accessory nerves has been a troublesome issue. After the recent developments in the microsurgical field, the detailed knowledge of the relationship of these nerves and the tumour has gained importance. The purpose of this study is to compare the visibility of each of these nerves.

METHODS

Thirty patients (M/F: 14/16; mean age 52.46 years) with complaints of vertigo, tinnitus, and hearing loss were examined with routine temporal magnetic resonance imaging (MRI) study. The imaging protocol consisted of 3-dimensional fast imaging with steady state acquisition in axial and sagittal oblique planes in addition to routine sequences. These images were transferred to a workstation and reformatted. Visibility of the nerves was evaluated by consensus of 2 radiologists who used an evaluation scale of 2 (excellently visible), 1 (partially visible), to 0 (not visible).

RESULTS

In 26 patients, both sides were scanned; in 4 patients, only one side was scanned. A total of 168 nerves were investigated. The rates for visualization for each nerve were as follows: glossopharyngeal nerve, 100% and 100%; vagus nerve, 67.9% and 100%; and accessory nerve, 10.8% and 83.85% on axial and sagittal oblique 3-dimensional fast imaging with steady state acquisition, respectively.

CONCLUSIONS

Glossopharyngeal, vagus, and accessory nerve assessment improved when images were obtained in the sagittal oblique plane to the jugular foramen.