Trigeminal neuralgia associated with the specific bridging pattern of transverse pontine vein: diagnostic value of three-dimensional multifusion volumetric imaging.

OBJECTIVES

We report the specific bridging pattern of a transverse pontine vein (TPV) associated with trigeminal neuralgia (TN), which was evaluated by 3-dimensional (3D) multifusion volumetric imaging (MFVI).

METHODS

In 3 cases with TN (V1 or V1-2 territory), constructive interference in steady state (CISS) imaging confirmed no arterial compression but indicated a vein draining into Meckel's cave. Virtual endoscopic (VE) analysis for CISS images and 3D MFVI (in 2 cases) including venous information was obtained by a multidetector row computed tomography (MDCT) system. Additionally, we investigated the bridging pattern of veins around Meckel's cave on 3D MFVI of 50 cerebellopontine angle (CPA) regions without any lesions.

RESULTS

In all 3 patients, VE of CISS or 3D MFVI identified a bridging vein from the TPV causing the focal deformity of the trigeminal nerve near Meckel's cave. All those patients achieved a pain-free state after surgically coagulating and cutting the vein. In investigating 3D MFVI of 50 CPA regions, this type of the bridging vein was found in 4 (8%) including the presented 2 cases.

CONCLUSIONS

The specific bridging pattern of the TPV draining into Meckel's cave can be associated with TN. The 3D MFVI analysis using venous information obtained by MDCT was useful to evaluate surgical anatomy including the offending vein which can be missed.