title: Unusual causes of trigeminal neuralgia treated by gamma knife radiosurgery. Report of two cases.
abstract: The purpose of this paper was to present two cases of secondary trigeminal neuralgia (TN) with an unusual origin and lesion location. In two cases TN was caused by lesions along the course of the trigeminal nerve within the pons and adjacent to the fourth ventricle. Both cases presented with typical TN. Brain magnetic resonance imaging revealed linear or wedge-shaped lesions adjacent to the fourth ventricle, extending anterolaterally and lying along the pathway of the intraaxial trigeminal fibers. The involvement of the nucleus of the spinal trigeminal tract and of the principal sensory trigeminal nucleus with segmental demyelination are suggested as possible causes for trigeminal pain in these cases. It is postulated that these lesions are the result of an old viral neuritis. The patients underwent gamma knife radiosurgery and their clinical responses have been encouraging to date.
authors.affiliation: Department of Neurosurgery and Brain Research Institute, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Chang
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Youngsul
authors.initials: Y
authors.lastname: Yoon
authors.forename: Yong Gou
authors.initials: YG
authors.lastname: Park
authors.forename: Sang Sup
authors.initials: SS
authors.lastname: Chung
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009443:Neuritis / Q000150:complications / Q000821:virology; D011149:Pons; D016634:Radiosurgery; D014277:Trigeminal Neuralgia / Q000209:etiology* / Q000473:pathology / Q000601:surgery*