Characterization of neurovascular compression in facial neuralgia patients by 3D high-resolution MRI and image fusion technique.

OBJECTIVE To describe the anatomical characteristics and patterns of neurovascular compression (NVC) in patients suffering trigeminal neuralgia (TN) by 3D high-resolution magnetic resonance imaging (MRI) method and image fusion technique. METHODS The anatomic structure of trigeminal nerve, brain stem and blood vessel was observed in 100 consecutive TN patients by 3D high resolution MRI (3D SPGR, contrast-enhanced T1 3D MP-RAGE and T2/T1 3D FIESTA). The 3D image sources were fused and visualized using 3D DOCTOR software. RESULTS One or several NVC sites, which usually appeared 0-9.8 mm away from brain stem, were found on the symptomatic side in 93% of the TN cases. Superior cerebellar artery was involved in 76% (71/93) of these cases. The other vessels including antero-inferior cerebellar artery, vertebral artery, basilar artery and veins also contributed to the occurrence of NVC. The NVC sites were found to be located in the proximal segment in 42% of these cases (39/93) and in the distal segment in 45% (42/93). Nerve dislocation or distortion was observed in 32% (30/93). CONCLUSIONS Various 3D high resolution MRI methods combined with the image fusion technique could provide pathologic anatomic information for the diagnosis and treatment of TN.