Preoperative evaluation of trigeminal neuralgia due to epidermoid tumor using a three dimensional fast advanced spin...

We report preoperative virtual images reconstructed from three-dimensional fast advanced spin echo (3D-FASE)and evaluate the cause of a trigeminal neuralgia due to an epidermoid tumor. A 60-year-old man had a 3-year-history of atypical trigeminal neuralgia in the left V2 region accompanied by a hypesthesia in the cheek. Neuroimaging demonstrated an epidermoid tumor in the left cerebello-pontine cistern. As the preoperative virtual images reconstructed from 3D-FASE images indicated that the superior cerebellar artery compressed the trigeminal nerve at the root entry zone, we carried out total removal of the tumor and microvascular decompression of the trigeminal nerve. It was possible to visualize the fine structures around the trigeminal nerve, because an epidermoid tumor shows a high intensity mass on 3D-FASE images. The simulated 3D images were useful in deciding upon the additional microvascular decompression surgery for trigeminal neuralgia after total removal of the epidermoid tumor.