Contact-free transposition and interposition techniques for trigeminal neuralgia: a systematic review.

Introduction: Surgical treatment for trigeminal neuralgia (TGN), by means of interposition of material between nerve and offending vessel, has been shown to be highly efficient. In recent years, treatment by means of vessel transposition has become more frequent, as in singular cases of recurrence, nerval reactions towards interposed material have been noted. In this review we research the classic microvascular decompression (MVD) techniques (interposition) as well as the more recent transposition and their effectiveness, considering patient outcomes as well as complications and recurrences.

Evidence Acquisition: We searched online databases MEDLINE and LIVIVO, using key words trigeminal neuralgia AND transposition/ AND sling/ AND non compressive technique/ AND microvascular decompression.

Evidence Synthesis: We included 8 studies for transposition and 20 studies for the interposition, combining for 2045 patients (302 for transposition and 1743 for interposition). 96.1% of patients in the transposition and 93.1% in the interposition group reported a positive outcome immediately postoperatively. At follow-up, 87.4% in the transposition group (follow-up 51.2 months) and 87.9% of patients in the interposition group (follow-up 36.5 months), reported a positive outcome. 16.2% of patients in the transposition and 13.1% in the interposition group had postoperative complications. Recurrence was reported in 5.6% of patients treated with transposition and 2.3% of patients treated with interposition.

Conclusions: Transposition presents similar results concerning short- and long-term patient satisfaction for treatment of TGN as well as similar numbers of complications of recurrences as interposition. Yet, current evidence is restricted to a few retrospective studies, thus, evidence is limited so far.