scholarly journals Gamma Knife Radiosurgery for Primary and Secondary Trigeminal Neuralgia

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Sunil K Gupta
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Microvascular Decompression ◽  
Treatment Modality ◽  
Pain Control ◽  
Treatment Options ◽  
Gamma Knife Radiosurgery ◽  
Clinical Criteria ◽  
Grade Iii

Abstract INTRODUCTION Trigeminal neuralgia has always been a disease of conflict from pathological and management perspectives. Despite advances in the radiological imaging, evidence from autopsy studies, and intraoperative findings, concrete answers are not in sight. GKRS has been a strong contender among available treatment options for the management of trigeminal neuralgia. METHODS All patients were evaluated on clinical criteria, BNI scale for intensity of pain, and facial hypoesthesia (if any) in a protocol-based manner. Only patients with BNI III to V were offered GKRS as a treatment modality. The Marseille point was targeted with a 70 to 90 Gy dose at 50% isodose. Patients were informed about all available treatment options with long-term prognosis and pain control rates. Patients in need of an immediate pain relief, in failed GKRS, and in a severe pain jeopardizing routine life and eating habits were not offered GKRS and were managed with microvascular decompression. RESULTS A total of 108 (65 males, 43 females) patients received GKRS with the Perfexion model since 2009. Eighty-two percent of the patients received GKRS for primary trigeminal neuralgia, while the rest received GKRS for secondary trigeminal neuralgia due to skull base lesions (meningioma, schwannoma, cerebellar AVM, etc). A total of 78% of the patients had preoperative BNI scale IV, while 19% and 3% of the patients had grade III and V scale pain, respectively. Ninety-four percent patients gained BNI scale III intensity pain within 3 mo of GKRS. The 3-yr pain control rate (BNI I-II) could be attained in 81% of the patients. Twelve percent of the patients remained in BNI grade III. Two patients needed redo GKRS for their pain recurrence. CONCLUSION It remains uncontested that MVD provides the best long-term pain-free control in patients of trigeminal neuralgia; however, GKRS remains a valuable feasible option for a selected group of patients. GKRS should be offered as an alternative treatment modality in patients not in urgent need of pain relief. In failed GKRS, authors did not encounter any difficulty in microvascular decompression.

Outcome Predictors After Gamma Knife Radiosurgery for Recurrent Trigeminal Neuralgia

Neurosurgery ◽  
2010 ◽  
Vol 67 (6) ◽  
pp. 1637-1645 ◽  
Author(s):  
Hideyuki Kano ◽  
Douglas Kondziolka ◽  
Huai-Che Yang ◽  
Oscar Zorro ◽  
Javier Lobato-Polo ◽  
...  
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Gamma Knife ◽  
Pain Control ◽  
Surgical Procedure ◽  
Gamma Knife Radiosurgery ◽  
Sensory Loss ◽  
Failed Surgery ◽  
Gamma Knife Stereotactic Radiosurgery

Abstract BACKGROUND: Trigeminal neuralgia (TN) that recurs after surgery can be difficult to manage. OBJECTIVE: To define management outcomes in patients who underwent gamma knife stereotactic radiosurgery (GKSR) after failing 1 or more previous surgical procedures. METHODS: We retrospectively reviewed outcomes after GKSR in 193 patients with TN after failed surgery. The median patient age was 70 years (range, 26-93 years). Seventy-five patients had a single operation (microvascular decompression, n = 40; glycerol rhizotomy, n = 24; radiofrequency rhizotomy, n = 11). One hundred eighteen patients underwent multiple operations before GKSR. Patients were evaluated up to 14 years after GKSR. RESULTS: After GKSR, 85% of patients achieved pain relief or improvement (Barrow Neurological Institute grade I-IIIb). Pain recurrence was observed in 73 of 168 patients 6 to 144 months after GKSR (median, 6 years). Factors associated with better long-term pain relief included no relief from the surgical procedure preceding GKSR, pain in a single branch, typical TN, and a single previous failed surgical procedure. Eighteen patients (9.3%) developed new or increased trigeminal sensory dysfunction, and 1 developed deafferentation pain. Patients who developed sensory loss after GKSR had better long-term pain control (Barrow Neurological Institute grade I-IIIb: 86% at 5 years). CONCLUSION: GKSR proved to be safe and moderately effective in the management of TN that recurs after surgery. Development of sensory loss may predict better long-term pain control. The best candidates for GKSR were patients with recurrence after a single failed previous operation and those with typical TN in a single trigeminal nerve distribution.

scholarly journals Repeat Gamma Knife radiosurgery versus microvascular decompression following failure of GKRS in trigeminal neuralgia: a systematic review and meta-analysis

2019 ◽  
Vol 131 (4) ◽  
pp. 1197-1206 ◽  
Author(s):  
Devi Prasad Patra ◽  
Amey Rajan Savardekar ◽  
Rimal Hanif Dossani ◽  
Vinayak Narayan ◽  
Nasser Mohammed ◽  
...  
Keyword(s):  
Systematic Review ◽  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Microvascular Decompression ◽  
Treatment Modality ◽  
Meta Analysis ◽  
Gamma Knife Radiosurgery ◽  
Facial Numbness ◽  
Retreatment Rate ◽  
Secondary Outcomes

OBJECTIVEGamma Knife radiosurgery (GKRS) has emerged as a promising treatment modality for patients with classical trigeminal neuralgia (TN); however, considering that almost half of the patients experience post-GKRS failure or lesion recurrence, a repeat treatment is typically necessary. The existing literature does not offer clear evidence to establish which treatment modality, repeat GKRS or microvascular decompression (MVD), is superior. The present study aimed to compare the overall outcome of patients who have undergone either repeat GKRS or MVD after failure of their primary GKRS; the authors do so by conducting a systematic review and meta-analysis of the literature and analysis of data from their own institution.METHODSThe authors conducted a systematic review and meta-analysis of the PubMed, Cochrane Library, Web of Science, and CINAHL databases to identify studies describing patients who underwent either repeat GKRS or MVD after initial failed GKRS for TN. The primary outcomes were complete pain relief (CPR) and adequate pain relief (APR) at 1 year. The secondary outcomes were rate of postoperative facial numbness and the retreatment rate. The pooled data were analyzed with R software. Bias and heterogeneity were assessed using funnel plots and I2 tests, respectively. A retrospective analysis of a series of patients treated by the authors who underwent repeat GKRS or MVD after post-GKRS failure or relapse is presented.RESULTSA total of 22 studies met the selection criteria and were included for final data retrieval and meta-analysis. The search did not identify any study that had directly compared outcomes between patients who had undergone repeat GKRS versus those who had undergone MVD. Therefore, the authors’ final analysis included two groups: studies describing outcome after repeat GKRS (n = 17) and studies describing outcome after MVD (n = 5). The authors’ institutional study was the only study with direct comparison of the two cohorts. The pooled estimates of primary outcomes were APR in 83% of patients who underwent repeat GKRS and 88% of those who underwent MVD (p = 0.49), and CPR in 46% of patients who underwent repeat GKRS and 72% of those who underwent MVD (p = 0.02). The pooled estimates of secondary outcomes were facial numbness in 32% of patients who underwent repeat GKRS and 22% of those who underwent MVD (p = 0.11); the retreatment rate was 19% in patients who underwent repeat GKRS and 13% in those who underwent MVD (p = 0.74). The authors’ institutional study included 42 patients (repeat GKRS in 15 and MVD in 27), and the outcomes 1 year after retreatment were APR in 80% of those who underwent repeat GKRS and 81% in those who underwent MVD (p = 1.0); CPR was achieved in 47% of those who underwent repeat GKRS and 44% in those who underwent MVD (p = 1.0). There was no difference in the rate of postoperative facial numbness or retreatment.CONCLUSIONSThe current meta-analysis failed to identify any superiority of one treatment over the other with comparable outcomes in terms of APR, postoperative facial numbness, and retreatment rates. However, MVD was shown to provide a better chance of CPR compared with repeat GKRS.

scholarly journals A Review of Percutaneous Treatments for Trigeminal Neuralgia

2013 ◽  
Vol 10 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Jason S. Cheng ◽  
Daniel A. Lim ◽  
Edward F. Chang ◽  
Nicholas M. Barbaro
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Microvascular Decompression ◽  
Pain Control ◽  
Gamma Knife Radiosurgery ◽  
Senior Author ◽  
Complication Rates ◽  
Percutaneous Procedures ◽  
Multiple Treatments ◽  
Effective Pain Relief

Abstract BACKGROUND: Common treatments for trigeminal neuralgia include percutaneous techniques, microvascular decompression, and Gamma Knife radiosurgery. Although microvascular decompression is considered the gold standard for treatment, percutaneous techniques remain an effective option for select patients. OBJECTIVE: To review the historical development, advantages, and limitations of the most common percutaneous procedures for trigeminal neuralgia: balloon compression (BC), glycerol rhizotomy (GR), and radiofrequency thermocoagulation (RF). METHODS: Publications reporting clinical outcomes after BC, GR, and RF were reviewed and included. Operative technique was based on the experience of the primary surgeon and senior author. RESULTS: All 3 percutaneous techniques (BC, GR, and RF) provide effective pain relief but differ in method and specificity of nerve injury. BC selectively injures larger pain fibers while sparing small fibers and does not require an awake, cooperative patient. Pain control rates up to 91% at 6 months and 66% at 3 years have been reported. RF allows somatotopic nerve mapping and selective division lesioning and provides pain relief in up to 97% of patients initially and 58% at 5 years. Multiple treatments improve outcomes but carry significant morbidity risk. GR offers similar pain-free outcomes of 90% at 6 months and 54% at 3 years but with higher complication rates (25% vs 16%) compared with BC. Advantages of percutaneous techniques include shorter procedure duration, minimal anesthesia risk, and in the case of GR and RF, immediate patient feedback. CONCLUSION: Percutaneous treatments for trigeminal neuralgia remain safe, simple, and effective for achieving good pain control while minimizing procedural risk.

203 Treatment Options Following Failed Gamma Knife Radiosurgery in Trigeminal Neuralgia: Long Term Outcome with Repeat Radiosurgery vs. Microvascular Decompression

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 254-255
Author(s):  
Devi Prasad Patra ◽  
Amey Savardekar ◽  
Shyamal C Bir ◽  
Anil Nanda
Keyword(s):  
Pain Relief ◽  
Microvascular Decompression ◽  
Treatment Options ◽  
Gamma Knife Radiosurgery ◽  
Additional Treatment ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Adequate Pain Relief ◽  
Prescription Dose

Abstract INTRODUCTION Primary treatment of trigeminal neuralgia with gamma knife radiosurgery (GKRS) is an accepted and effective modality, but is associated with a significant failure rate. Many of the patients ultimately require additional treatment for adequate pain relief. The present paper discusses the long term outcome of this group of patients who are treated with either repeat GKRS or microvascular decompression (MVD) as a secondary procedure. METHODS Using the retrospective database, the clinical data was analyzed of the patients who underwent GKRS at our institute between January 2000 and June 2016. The initial GKRS plan included median prescription dose of 80 Gy at a single iso-center using 4 mm collimator. The patients who did not improve after initial therapy and maximal medication dosage were offered either repeat radiosurgery or MVD. Repeat radiosurgery included a similar plan but a reduced median prescription dose of 40 Gy. Long term pain relief was measured using Marseille's score. Multiple factors including demographic factors, the type of pain, post GKRS facial numbness, treatment interval were analyzed to predict association with the final outcome. RESULTS >In the study preriod, a total of 198 patients underwent GKRS for trigeminal neuralgias. Among these patients 42 (21.2%) patients had treatment failure and required additional treatment. The median interval of subsequent interventions was 16 months (range 2 months to 154 months). Six patients (14.2%) required repeat treatment after 5 years of initial treatment. Out of 42 failed GKRS patients, 15 (35.7%) underwent repeat radiosurgery and 27 (64.3%) underwent MVD. The mean follow up duration was 4.3 years. Overall, 34 patients (81%) improved and had adequate pain relief (Marseille's score III or better) after the second procedure. The rate of adequate pain relief after repeat GKRS and microvascular decompression were 86.6% and 77.7% respectively (P = 0.68). Univariate analysis failed to reveal any significant predictor for pain relief after second treatment. CONCLUSION Repeat GKRS and MVD both are valid treatment options after failed initial radiosurgery, with no difference in long term outcome. Unless specifically indicated, repeat GKRS being noninvasive, may be considered over microvascular decompression.

Temporal disconnection between pain relief and trigeminal nerve microstructural changes after Gamma Knife radiosurgery for trigeminal neuralgia

2020 ◽  
Vol 133 (3) ◽  
pp. 727-735
Author(s):  
Peter Shih-Ping Hung ◽  
Sarasa Tohyama ◽  
Jia Y. Zhang ◽  
Mojgan Hodaie
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Pain Intensity ◽  
Gamma Knife ◽  
Trigeminal Nerve ◽  
Diffusion Tensor ◽  
Gamma Knife Radiosurgery ◽  
Time Points ◽  
Microstructural Effect

OBJECTIVEGamma Knife radiosurgery (GKRS) is a noninvasive surgical treatment option for patients with medically refractive classic trigeminal neuralgia (TN). The long-term microstructural consequences of radiosurgery and their association with pain relief remain unclear. To better understand this topic, the authors used diffusion tensor imaging (DTI) to characterize the effects of GKRS on trigeminal nerve microstructure over multiple posttreatment time points.METHODSNinety-two sets of 3-T anatomical and diffusion-weighted MR images from 55 patients with TN treated by GKRS were divided within 6-, 12-, and 24-month posttreatment time points into responder and nonresponder subgroups (≥ 75% and < 75% reduction in posttreatment pain intensity, respectively). Within each subgroup, posttreatment pain intensity was then assessed against pretreatment levels and followed by DTI metric analyses, contrasting treated and contralateral control nerves to identify specific biomarkers of successful pain relief.RESULTSGKRS resulted in successful pain relief that was accompanied by asynchronous reductions in fractional anisotropy (FA), which maximized 24 months after treatment. While GKRS responders demonstrated significantly reduced FA within the radiosurgery target 12 and 24 months posttreatment (p < 0.05 and p < 0.01, respectively), nonresponders had statistically indistinguishable DTI metrics between nerve types at each time point.CONCLUSIONSUltimately, this study serves as the first step toward an improved understanding of the long-term microstructural effect of radiosurgery on TN. Given that FA reductions remained specific to responders and were absent in nonresponders up to 24 months posttreatment, FA changes have the potential of serving as temporally consistent biomarkers of optimal pain relief following radiosurgical treatment for classic TN.

scholarly journals Efficacy of primary microvascular decompression versus subsequent microvascular decompression for trigeminal neuralgia

2017 ◽  
Vol 126 (5) ◽  
pp. 1691-1697 ◽  
Author(s):  
Debebe Theodros ◽  
C. Rory Goodwin ◽  
Matthew T. Bender ◽  
Xin Zhou ◽  
Tomas Garzon-Muvdi ◽  
...  
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Trigeminal Nerve ◽  
Microvascular Decompression ◽  
Pain Control ◽  
Surgical Intervention ◽  
Patient Records ◽  
Duration Of Symptoms ◽  
Facial Numbness ◽  
Lancinating Pain

OBJECTIVETrigeminal neuralgia (TN) is characterized by intermittent, paroxysmal, and lancinating pain along the distribution of the trigeminal nerve. Microvascular decompression (MVD) directly addresses compression of the trigeminal nerve. The purpose of this study was to determine whether patients undergoing MVD as their first surgical intervention experience greater pain control than patients who undergo subsequent MVD.METHODSA retrospective review of patient records from 1998 to 2015 identified a total of 942 patients with TN and 500 patients who underwent MVD. After excluding several cases, 306 patients underwent MVD as their first surgical intervention and 175 patients underwent subsequent MVD. Demographics and clinicopathological data and outcomes were obtained for analysis.RESULTSIn patients who underwent subsequent MVD, surgical intervention was performed at an older age (55.22 vs 49.98 years old, p < 0.0001) and the duration of symptoms was greater (7.22 vs 4.45 years, p < 0.0001) than for patients in whom MVD was their first surgical intervention. Patients who underwent initial MVD had improved pain relief and no improvement in pain rates compared with those who had subsequent MVD (95.8% and 4.2% vs 90.3% and 9.7%, respectively, p = 0.0041). Patients who underwent initial MVD had significantly lower rates of facial numbness in the pre- and postoperative periods compared with patients who underwent subsequent MVD (p < 0.0001). The number of complications in both groups was similar (p = 0.4572).CONCLUSIONSThe results demonstrate that patients who underwent other procedures prior to MVD had less pain relief and a higher incidence of facial numbness despite rates of complications similar to patients who underwent MVD as their first surgical intervention.

Predictors of outcome in surgically managed patients with typical and atypical trigeminal neuralgia: comparison of results following microvascular decompression

2002 ◽  
Vol 96 (3) ◽  
pp. 527-531 ◽  
Author(s):  
Elizabeth C. Tyler-Kabara ◽  
Amin B. Kassam ◽  
Michael H. Horowitz ◽  
Louise Urgo ◽  
Constantinos Hadjipanayis ◽  
...  
Keyword(s):  
Postoperative Pain ◽  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Microvascular Decompression ◽  
Long Term Results ◽  
Content Type ◽  
Significant Pain ◽  
Fine Print

Object. Microvascular decompression (MVD) has become one of the primary treatments for typical trigeminal neuralgia (TN). Not all patients with facial pain, however, suffer from the typical form of this disease; many patients who present for surgical intervention actually have atypical TN. The authors compare the results of MVD performed for typical and atypical TN at their institution. Methods. The results of 2675 MVDs in 2264 patients were reviewed using information obtained from the department database. The authors examined immediate postoperative relief in 2003 patients with typical and 672 with atypical TN, and long-term follow-up results in patients for whom more than 5 years of follow-up data were available (969 with typical and 219 with atypical TN). Outcomes were divided into three categories: excellent, pain relief without medication; good, mild or intermittent pain controlled with low-dose medication; and poor, no or poor pain relief with large amounts of medication. The results for typical and atypical TN were compared and patient history and pain characteristics were evaluated for possible predictive factors. Conclusions. In this study, MVD for typical TN resulted in complete postoperative pain relief in 80% of patients, compared with 47% with complete relief in those with atypical TN. Significant pain relief was achieved after 97% of MVDs in patients with typical TN and after 87% of these procedures for atypical TN. When patients were followed for more than 5 years, the long-term pain relief after MVD for those with typical TN was excellent in 73% and good in an additional 7%, for an overall significant pain relief in 80% of patients. In contrast, following MVD for atypical TN, the long-term results were excellent in only 35% of cases and good in an additional 16%, for overall significant pain relief in only 51%. Memorable onset and trigger points were predictive of better postoperative pain relief in both atypical and typical TN. Preoperative sensory loss was a negative predictor for good long-term results following MVD for atypical TN.

scholarly journals Microvascular decompression in trigeminal neuralgia: predictors of pain relief, complication avoidance, and lessons learned

2021 ◽  
Author(s):  
Johannes Herta ◽  
Tobias Schmied ◽  
Theresa Bettina Loidl ◽  
Wei-te Wang ◽  
Wolfgang Marik ◽  
...  
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Microvascular Decompression ◽  
The Elderly ◽  
Pain Intensity Score ◽  
Complication Rates ◽  
Safe Procedure ◽  
Neurovascular Conflict ◽  
Paroxysmal Pain

Abstract Objective To analyze characteristics associated with long-term pain relief after microvascular decompression (MVD) for trigeminal neuralgia (TGN). Description of associated morbidity and complication avoidance. Methods One hundred sixty-five patients with TGN underwent 171 MVD surgeries at the authors’ institution. Patient characteristics and magnetic resonance imaging (MRI) datasets were obtained through the hospital’s archiving system. Patients provided information about pre- and post-operative pain characteristics and neurologic outcome. Favorable outcome was defined as a Barrow Neurological Institute (BNI) pain intensity score of I to III with post-operative improvement of I grade. Results Type of TGN pain with purely paroxysmal pain (p = 0.0202*) and TGN classification with classical TGN (p = 0.0372*) were the only significant predictors for long-term pain relief. Immediate pain relief occurred in 90.6% of patients with a recurrence rate of 39.4% after 3.5 ± 4.6 years. MRI reporting of a neurovascular conflict had a low negative predictive value of 39.6%. Mortality was 0% with major complications observed in 8.2% of patients. Older age was associated with lower complication rates (p = 0.0009***). Re-MVD surgeries showed improved long-term pain relief in four out of five cases. Conclusions MVD is a safe and effective procedure even in the elderly. It has the unique potential to cure TGN if performed on a regular basis, and if key surgical steps are respected. Early MVD should be offered in case of medical treatment failure and paroxysmal pain symptoms. The presence of a neurovascular conflict on MRI is not mandatory. In case of recurrence, re-MVD is a good treatment option that should be discussed with patients. Highlights • Long-term analysis of pain relief after MVD. • Positive predictors for outcome: classical TGN and purely paroxysmal pain. • Presence of neurovascular conflict in MRI is not mandatory for MVD surgery. • Analysis of complications and surgical nuances for avoidance. • MVD is a safe procedure also in the elderly.

scholarly journals Early postsurgical diffusivity metrics for prognostication of long-term pain relief after Gamma Knife radiosurgery for trigeminal neuralgia

2019 ◽  
Vol 131 (2) ◽  
pp. 539-548 ◽  
Author(s):  
Sarasa Tohyama ◽  
Peter Shih-Ping Hung ◽  
Jidan Zhong ◽  
Mojgan Hodaie
Keyword(s):  
Pain Relief ◽  
Trigeminal Neuralgia ◽  
Fractional Anisotropy ◽  
Gamma Knife ◽  
Trigeminal Nerve ◽  
Gamma Knife Radiosurgery ◽  
Mean Diffusivity ◽  
Clinical Effectiveness ◽  
Radial Diffusivity

OBJECTIVEGamma Knife radiosurgery (GKRS) is an important treatment modality for trigeminal neuralgia (TN). Current longitudinal assessment after GKRS relies primarily on clinical diagnostic measures, which are highly limited in the prediction of long-term clinical benefit. An objective, noninvasive, predictive tool would be of great utility to advance the clinical management of patients. Using diffusion tensor imaging (DTI), the authors’ aim was to determine whether early (6 months post-GKRS) target diffusivity metrics can be used to prognosticate long-term pain relief in patients with TN.METHODSThirty-seven patients with TN treated with GKRS underwent 3T MRI scans at 6 months posttreatment. Diffusivity metrics of fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity were extracted bilaterally from the radiosurgical target of the affected trigeminal nerve and its contralateral, unaffected nerve. Early (6 months post-GKRS) diffusivity metrics were compared with long-term clinical outcome. Patients were identified as long-term responders if they achieved at least 75% reduction in preoperative pain for 12 months or longer following GKRS.RESULTSTrigeminal nerve diffusivity at 6 months post-GKRS was predictive of long-term clinical effectiveness, where long-term responders (n = 19) showed significantly lower fractional anisotropy at the radiosurgical target of their affected nerve compared to their contralateral, unaffected nerve and to nonresponders. Radial diffusivity and mean diffusivity, correlates of myelin alterations and inflammation, were also significantly higher in the affected nerve of long-term responders compared to their unaffected nerve. Nonresponders (n = 18) did not exhibit any characteristic diffusivity changes after GKRS.CONCLUSIONSThe authors demonstrate that early postsurgical target diffusivity metrics have a translational, clinical value and permit prediction of long-term pain relief in patients with TN treated with GKRS. Importantly, an association was found between the footprint of radiation and clinical effectiveness, where a sufficient level of microstructural change at the radiosurgical target is necessary for long-lasting pain relief. DTI can provide prognostic information that supplements clinical measures, and thus may better guide the postoperative assessment and clinical decision-making for patients with TN.

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