Vascular contact with the trigeminal nerve at the pons is known to cause trigeminal neuralgia; however, this finding also is present in some asymptomatic subjects. We evaluated the usefulness of high-resolution MR imaging and MR angiography of the posterior fossa to determine the presence or absence of vascular contact with the fifth cranial nerve at the pons in patients with trigeminal neuralgia and in control subjects.The trigeminal nerves in 40 symptomatic patients and 114 asymptomatic control subjects were examined for the presence or absence of vascular contact at the pons by using three dimension (3D) fast inflow with steady-state precession (FISP) imaging. Imaging parameters were 35/7/15 degrees (TR/TE/flip angle) with a slab thickness of 55 mm and 64 partitions. Contrast-enhanced imaging was done in 10 of 12 patients with normal findings on an unenhanced scan. Axial, coronal, sagittal, and maximum-intensity-projection images were reviewed by two observers who had no knowledge of the clinical detai...