MR cisternography in the posterior fossa: the evaluation of trigeminal neurovascular compression.

AIM To evaluate the utility of 3D-magnetic resonance cisternography(MRC) of posterior cranial fossa in visualizing trigeminal neurovascular compression in patients with trigeminal neuralgia. MATERIAL AND METHODS 146 consecutive patients in the period from June 2010 to July 2011 in our institute diagnosed with trigeminal neuralgia underwent MRC on the posterior cranial fossa. MR devices used for MRC included two sets of 3.0 tesla and one set of 1.5 tesla. The hydrography sequences for MRC included 3D-SPACE and 3D-DRIVE. RESULTS In total, 75 patients (51.4%) were found with trigeminal neurovascular compression on MRC. Among them, 25 patients underwent microvascular decompression. Intraoperatively, 20 patients (80%) had related arteries consistent with imaging manifestations on MRC. Nevertheless, the arterial compression combined with petrosal vein could not be identified on MRC in 3 of the 20 patients. In the inconsistent 5 cases, the involved vessels were confirmed as superior petrosal veins during the surgery. CONCLUSION 3D-MRC has prominent clinical value in determining the trigeminal neurovascular compression and identifying the related vessels. However, MRC does have certain limitations on identifying petrosal vein compression.