gms | German Medical Science

73. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Griechischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

29.05. - 01.06.2022, Köln

Diffusion MRI indicating structural nerve recovery after microvascular decompression in trigeminal neuralgia

Erholung der Faserintegrität nach mikrochirurgischer Dekompression bei Trigeminusneuralgie

Meeting Abstract

  • presenting/speaker Franziska Dirks - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Ricardo Louçäo - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Kathrin Burg - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Niklas von Spreckelsen - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Mauritius Hoevels - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Thorsten Lichtenstein - Universitätsklinikum Köln, Institut für Diagnostische und Interventionelle Radiologie, Köln, Deutschland
  • Roland Goldbrunner - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Jürgen A. Hampl - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland
  • Carolin Weiß-Lucas - Universitätsklinikum Köln, Zentrum für Neurochirurgie, Köln, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 73. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Griechischen Gesellschaft für Neurochirurgie. Köln, 29.05.-01.06.2022. Düsseldorf: German Medical Science GMS Publishing House; 2022. DocV185

doi: 10.3205/22dgnc179, urn:nbn:de:0183-22dgnc1792

Published: May 25, 2022

© 2022 Dirks et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Objective: Previous studies using MRI techniques such as diffusion tensor imaging (DTI) as a diagnostic tool for trigeminal neuralgia found a significantly lower fractional anisotropy (FA) in the root-entry-zone of the affected nerve. We hypothesized that postoperative DTI might show an increase in fibre directionality, corresponding to structural recovery of the trigeminal nerve, going along with clinical improvement.

Methods: 62 patients (26 male, 36 female, median age 64 years) who underwent microvascular decompression were assessed using a standardized questionnaire including a numeric rating scale and a brief pain inventory-facial and an MRI (3D-T1, -T2, DTI) at three points in time each: MRI/questionnaire 1 day preoperatively, MRI 48 hours postoperatively / questionnaire 7 days postoperatively, and MRI/questionnaire 3 months postoperatively. All patients were operated using an autologous cushion (muscle patch), allowing for widely artefact-free postoperative diffusion MRI. Data processing was performed using FSL. Bilateral FA-values were measured in the root-entry-zone and the cisternal segment of the brainstem. Regions of interest (ROIs) were drawn in three-dimensional space using the software iPlan, and a standardized ROI volume of 0.02 cm2.

Results: Pain relief was achieved in 93.61% of the patients whereas 6.39% were defined as partial or non-responders. Overall, a significant decrease in pain levels was found at both 7 days (by 90.3 ± 17.9%; p<0.001) and 3 months postoperatively (by 83.0 ± 34.1%; p<0.001). FA-values of the ipsilateral trigeminal nerve (root-entry-zone) showed a significant increase after 3 months (p<0.05), as opposed to no significant change of the FA on the contralateral side.

Conclusion: Pain relief achieved by microvascular decompression of the trigeminal nerve (using interposition of muscle tissue) is reflected by a significant improvement of ipsilateral fibre integrity. This suggests that the clinical success of surgery translates to a structural recovery of the affected trigeminal nerve in the root entry zone.