Microsurgical posterior fossa exploration for trigeminal neuralgia: A study on 48 cases

The authors present their experience in the microsurgical treatment of trig eminal neuralgia (TGN). Over the last five years 48 patients were explored and 34 (71 %) underwent microvascular decompression (MVD) for significant a rterial or venous conflicts. The remaining 14 patients (29%) underwent part ial sensory rhizotomy (PSR) because of negative intraoperative findings (si mple contact or no conflict). Excellent or good immediate outcomes were ach ieved in 87.5 and 12.5% of patients, respectively. Of the three severe recu rrences observed during the follow-up period (24.7 months; range: 7-65 mont hs), two underwent percutaneous microcompression and one posterior fossa re exploration, which revealed teflon-induced recompression. None of the PSR c ases experienced incapacitating face numbness. MVD, an extremely effective procedure in the immediate post-operative period, is burdened in the long t erm by 20 % recurrences, the majority occurring within two years from surge ry. We believe that careful intraoperative evaluation of the conflict entit y could be the key to achieve a significant reduction of recurrences: overe stimation of simple vascular contact of doubtful etiologic relevance, may l ead to ineffective decompression and unsatisfactory results. In our opinion PSR should be preferred to percutaneous treatments in cases of negative ex ploration (contact or no conflict). In accordance with others we observed t hat section of half or less of the inferolateral " portio major " allows lo ng-lasting pain relief and good preservation of sensory function.