Evaluation of jugular foramen nerves by using b-FFE, T2-weighted DRIVE, T2-weighted FSE and post-contrast T1-weighted MRI sequences.

3 T he ninth, tenth and eleventh nerves have much in common functionally and share a nucleus that originates in the medulla. They are therefore considered as a group and are evaluated as a region. Together, they enter the jugular foramen (1, 2). Detecting the individual cranial nerves in the intraforaminal portion of the jugular foramen is useful in diagnostic imaging; however, visualization using conventional magnetic resonance imaging (MRI) protocols does not provide adequate details of the individual nerves (3, 4). With the rapid development of MRI technology, newer 2D-3D, high spatial resolution, strong T2-weighted (T2W) sequences have been developed; these include 3D-CISS (three-dimensional constructive interference in steady state), 3D-MP-RAGE (three-dimensional magnetization-prepared rapid gradient-echo) and 3D-FIESTA (three-dimensional fast imaging employing steady-state acquisition) (3–7). Both balanced fast-field echo (bFFE) and 3D-T2W-driven equilibrium radiofrequency reset pulse (DRIVE) sequences can also provide heavily T2-weighted, good MR cisternographic images and can be used to evaluate cranial nerve nuclei and root entry zones (6–8). In this study, we aimed to assess the most efficient sequence for evaluating and visualizing the ninth, tenth and eleventh nerves. For this purpose, we evaluated images of this area on both sides of 100 patients. We applied bFFE, 3D-T2W-DRIVE, 2D-T2W-TSE and post-contrast T1weighted (T1W) sequences and chose the best sequence for precisely visualizing all three nerves.