Gamma Knife surgery used as primary and repeated treatment for idiopathic trigeminal neuralgia

Abstract

Object The purpose of this study was to assess the outcome of idiopathic trigeminal neuralgia (TN) treated with Gamma Knife surgery (GKS) as a primary and repeated treatment modality with a mean follow-up of 5.7 years. Methods Between July 1999 and September 2005, a total of 89 patients with idiopathic TN underwent GKS as a primary treatment. The entry zone of the TN was targeted with a 4-mm collimator and treated with a maximal dose of 60–90 Gy (mean 79 Gy). The dose to the pontine margin was always kept < 15 Gy. Twenty patients received repeated GKS for recurrent or residual pain with a maximal dose of 40–76 Gy (mean 52 Gy). For the second procedure, the target was positioned at the same location as the first treatment. Results The mean follow-up period was 68 months (range 32–104 months). Sixty-nine (77.5%) of the 89 patients experienced a favorable response, as follows: 50 (56%) had excellent, 12 (13.5%) had good, and 7 (7.8%) had fair outcomes. The mean time to pain relief was 1.1 months (range 2 days–6 months). No significant correlation, but more likely a tendency, was found between the dose and pain relief (p = 0.08). Also, no correlation was noted for facial numbness (p = 0.77). The mean follow-up period after repeated GKS was 60 months (range 32–87 months). Outcomes after repeated GKS were excellent in 11 patients (55%) and good in 1 (5%). Seven patients experienced facial numbness. No correlation was found between the additive dose and pain relief (p = 0.24) or facial numbness (p = 0.15). Final outcomes of primary and repeated GKS were excellent in 61 (68.5%), good in 13 (14.6%), and fair in 7 (7.9%). In total, 91% of the patients were successfully treated with this method. There was no statistical significance for efficacy between primary and repeated GKS (p = 0.65), but there was a significant difference for facial numbness (p = 0.007). Conclusions Gamma Knife surgery established durable pain relief when used as a primary and repeated surgery. Treatment was successful for a total of 91% of patients at a mean follow-up of 5.7 years, but facial numbness was also relatively higher.

Feasibility of Multiple Repeat Gamma Knife Radiosurgeries for Trigeminal Neuralgia: A Case Report and Review of the Literature

“…However, successful retreatment of patients in whom the initial GK treatment fails is also feasible [9], as was illustrated in this case with the second GKRS. Overall, repeat GKRS has been shown to provide significant pain relief in more than 2/3 of patients [10, 11], with some studies showing similar [12, 13] and others showing better [11] overall facial-pain outcomes than primary radiosurgery. Studies have also demonstrated that lack of a prior neurosurgical procedure was predictive of better pain control [14, 15].…”

Repeat Gamma-Knife Radiosurgery for Refractory or Recurrent Trigeminal Neuralgia with Consideration About the Optimal Second Dose

“…Two studies published only with two year interval from single center was reduced to one vote (17,18). Partially duplicate studies including repeat GKS patients as a subgroup was also considered as a vote (25).…”

“…Case reports with one or several cases were excluded and studies with at least 10 patients were included (42). Partially duplicate studies from the same GKS center were considered as single vote (17, 18,25,42).…”

“…For recurrent or refractory trigeminal neuralgia, repeat gamma-knife radiosurgery (GKS) is known as an effective treatment with low complication rate (3,4,8,15,17,18,20,34,36,37,41,(44)(45)(46)(47).…”

Clinical Outcomes of Gamma Knife Radiosurgery in the Treatment of Patients with Trigeminal Neuralgia

“…As expected, similar results were found in the other study by Fountas et al [37]; however, no prior radiosurgical procedures were performed in the patient group with a history of prior procedures. Huang et al [38] conducted a study where 89 patients with idiopathic TN were treated with GKRS as an initial management approach, 20 of which underwent a subsequent GKRS procedure for facial pain recurrence. Following the initial radiosurgical procedure, 50 patients (56%) had an excellent response, 12 patients (13.5%) had a good response, and 7 patients (7.9%) had a fair response.…”