TY - JOUR T1 - High-Resolution MRI Findings following Trigeminal Rhizotomy JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 1920 LP - 1924 DO - 10.3174/ajnr.A4868 VL - 37 IS - 10 AU - B.G. Northcutt AU - D.P. Seeburg AU - J. Shin AU - N. Aygun AU - D.A. Herzka AU - D. Theodros AU - C.R. Goodwin AU - C. Bettegowda AU - M. Lim AU - A.M. Blitz Y1 - 2016/10/01 UR - http://www.ajnr.org/content/37/10/1920.abstract N2 - BACKGROUND AND PURPOSE: Patients with trigeminal neuralgia often undergo trigeminal rhizotomy via radiofrequency thermocoagulation or glycerol injection for treatment of symptoms. To date, radiologic changes in patients with trigeminal neuralgia post-rhizotomy have not been described, to our knowledge. The aim of this study was to evaluate patients after trigeminal rhizotomy to characterize post-rhizotomy changes on 3D high-resolution MR imaging.MATERIALS AND METHODS: A retrospective review of trigeminal neuralgia protocol studies was performed in 26 patients after rhizotomy compared with 54 treatment-naïve subjects with trigeminal neuralgia. Examinations were reviewed independently by 2 neuroradiologists blinded to the side of symptoms and treatment history. The symmetry of Meckel's cave on constructive interference in steady-state and the presence of contrast enhancement within the trigeminal nerves on volumetric interpolated breath-hold examination images were assessed subjectively. The signal intensity of Meckel's cave was measured on coronal noncontrast constructive interference in steady-state imaging on each side.RESULTS: Post-rhizotomy changes included subjective clumping of nerve roots and/or decreased constructive interference in steady-state signal intensity within Meckel's cave, which was identified in 17/26 (65%) patients after rhizotomy and 3/54 (6%) treatment-naïve patients (P < .001). Constructive interference in steady-state signal intensity within Meckel's cave was, on average, 13% lower on the side of the rhizotomy in patients posttreatment compared with a 1% difference in controls (P < .001). Small regions of temporal encephalomalacia were noted in 8/26 (31%) patients after rhizotomy and 0/54 (0%) treatment-naïve patients (P < .001).CONCLUSIONS: Post-trigeminal rhizotomy findings frequently include nerve clumping and decreased constructive interference in steady-state signal intensity in Meckel's cave. Small areas of temporal lobe encephalomalacia are encountered less frequently.CISSconstructive interference in steady-stateSIsignal intensityVIBEvolumetric interpolated breath-hold examinationSPACEsampling perfection with application-optimized contrasts by using different flip angle evolution ER -