Gamma knife radiosurgery for trigeminal neuralgia: first case series from Latin America

Arq Neuropsiquiatr. 2019 May 13;77(4):232-238. doi: 10.1590/0004-282X20190027.

Abstract

Introduction: Gamma Knife® radiosurgery (GKRS) for trigeminal neuralgia is an effective treatment with at least a 50% reduction of pain in 75-95% of patients.

Objective: To present the first series of patients treated for trigeminal neuralgia using GKRS in Latin America.

Methods: Retrospective analysis. Analysis consisted of time to improvement of symptoms, best Barrow Neurological Institute scale (BNI) score after procedure, time without pain, time to recurrence and post-procedural hypoesthesia.

Results: Nineteen cases of classical trigeminal neuralgia were analyzed and three cases of symptomatic trigeminal neuralgia were described. Mean time from symptom onset to radiosurgery was 99.6 months, and 78.9% of patients had undergone invasive procedures before treatment. Patients were followed for a mean of 21.7 months. BNI I was achieved in 36.8%, IIIa in 21.1%, IIIb in 21.1%, IV in 5.3% and V in 15.7%. New hypoesthesia developed in 12.1% patients, which was associated with achieving BNI I after the procedure (p < 0.05). Time from diagnosis to GKRS was higher in patients who failed to achieve BNI I (143 vs. 76 months). The distance from the root entry zone in patients who achieved BNI I was greater than patients who did not (1.94 vs. 1.14 mm). Mean distance from the root entry zone in patients with new hypoesthesia was 2.85 mm vs. 1.06 mm (p = 0.06).

Conclusion: Clinical response to GKRS is related to the time between diagnosis and procedure, thus its indication should be considered early in the management of these patients.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Dose-Response Relationship, Radiation
  • Female
  • Follow-Up Studies
  • Humans
  • Latin America
  • Male
  • Middle Aged
  • Pain Measurement
  • Radiosurgery / methods*
  • Recurrence
  • Reproducibility of Results
  • Retrospective Studies
  • Rhizotomy / methods
  • Time Factors
  • Treatment Outcome
  • Trigeminal Neuralgia / radiotherapy*