A Systematic Review of the Management of Trigeminal Neuralgia in Patients with Multiple Sclerosis

Repeat Gamma Knife radiosurgery for recurrent trigeminal neuralgia in patients with multiple sclerosis: a single-center retrospective study

PURPOSE

Gamma Knife radiosurgery (GKRS) has emerged as an effective treatment option for trigeminal neuralgia (TN) in patients with multiple sclerosis (MS). To date, the outcomes of repeat GKRS for patients with TN and MS with recurrent pain have been investigated in a few patients. This study aims to report the outcomes and predictive factors of pain reduction for MS patients undergoing repeat GKRS for recurrent TN.

METHODS

Eighteen patients with MS underwent repeat GKRS for recurrent TN. A retrospective chart review and telephone interviews were conducted to determine background medical history, dosimetric data, and outcomes of the procedure. Facial pain and sensory function were evaluated using the Barrow Neurological Institute (BNI) scales.

RESULTS

Fifteen patients achieved a BNI pain score of IIIa or better, indicating pain reduction, within a median period of 21 days after repeat GKRS. The maximum dose for repeat GKRS ranged from 70 to 85 Gy. Pain recurred in 5 patients after a median period of 12 months after GKRS. Percentages of patients with pain reduction at 1, 2, 3, 5, and 7 years were 60%, 60%, 50%, 50%, and 50%, respectively. Older age at repeat GKRS predicted sustained pain reduction (P = 0.01). Seven patients developed facial sensory disturbances, which were bothersome in two patients.

CONCLUSIONS

Repeat GKRS may be used as an effective treatment modality for prolonging the duration of pain reduction time in patients with MS and TN. After repeat GKRS, facial sensory disturbances are common; however, they are often not bothersome.

Effectiveness of gamma knife radiosurgery in the management of trigeminal neuralgia associated with multiple sclerosis: a systematic review and meta-analysis

BACKGROUND

Trigeminal neuralgia (TN) is a chronic condition characterized by intense facial pain akin to electric shocks, often associated with the trigeminal nerve. It can be either idiopathic or secondary, with multiple sclerosis (Ms) being a significant contributing factor. Non-responsive patients may opt for minimally invasive procedures, such as gamma knife radiosurgery (GKRS), which offers precise, non-invasive treatment and is frequently chosen as a primary approach. This meta-analysis evaluates the long-term efficacy of GKRS in TN management in Ms patients.

METHODS

We conducted a focused search across various databases. Inclusion criteria encompassed studies with ≥ 30 patients using GKRS for TN in Ms, reporting pertinent clinical outcomes. Primary outcomes assessed GKRS efficacy through Barrow Neurological Institute Pain scores. Secondary outcomes encompassed bothersome numbness, facial numbness, and recurrence. Data analysis employed OpenMeta, random effect models, and odds ratios with 95% confidence intervals. Heterogeneity was assessed using I2 statistics.

RESULTS

Fourteen studies with 752 cases of GKRS for TN were included. Regarding the outcomes, 83% of patients experienced a positive initial pain response, while the overall treatment success rate was 51%. Additionally, 19.6% of patients reported facial numbness, 4.1% experienced bothersome numbness, and 40% faced recurrence. The odds ratio for positive initial pain response was 0.83 (95% CI, 0.76-0.89), while for treatment success, it was 0.51 (95% CI, 0.379-0.639). Facial numbness had an odds ratio of 0.196 (95% CI, 0.130-0.262), bothersome numbness had an odds ratio of 0.041 (95% CI, 0.013-0.069), and recurrence had an odds ratio of 0.403 (95% CI, 0.254-0.551).

CONCLUSIONS

In conclusion, treating trigeminal neuralgia in multiple sclerosis patients remains challenging. GKRS shows promise, but customized treatment approaches tailored to individual patient characteristics are urgently needed to address the unique challenges of this condition.

Management of trigeminal neuralgia: A multi-centre case study in general practice

Background and aims

Patients often first present with symptoms of trigeminal neuralgia (TN) to primary care. However, there has been little research to determine whether the diagnosis and management of this condition is carried out according to current guidelines. Furthermore, there is little up-to-date information regarding the prevalence of TN in the UK. The aim is to estimate the prevalence of TN and to audit the diagnosis and management process of TN in primary care.

Methods

Between 2019 and 2020 a search was made at five UK GP practices with a total patient population of 55,842 using EMIS and SystmOne patient record systems to review patient consultations to identify patients coded with TN or facial pain (FP). These records were reviewed to ascertain the basis for diagnosis, management in primary care and referral to secondary care.

Results

157 patients were identified; 54 coded with FP and 103 with TN. These results indicate a prevalence of 22.3 in 10,000. There was no difference in documented symptoms between the two groups. Seven patients had all ICDH3 criteria recorded, with two meeting the requirements for TN diagnosis. 58.8% of patients with TN were started on carbamazepine, the current gold standard treatment, compared with 16.7% in the FP group. 38.2% of TN patients were referred to a range of different specialities.

Conclusion

The prevalence of TN may be higher than previously thought. Key diagnostic criteria are often omitted, leading to potential misdiagnosis or delays in diagnosis. Relatively few referrals are made, though all patients should be considered for imaging.

The role of multiple sclerosis subtype in microvascular decompression outcomes for patients with trigeminal neuralgia

OBJECTIVES

While patients with concomitant trigeminal neuralgia (TN) and multiple sclerosis (MS) are understood to experience a more intractable pain phenotype, whether TN pain outcomes differ by the presenting MS subtype is not well characterized. This study's objective is to compare post-operative pain and numbness outcomes following microvascular decompression (MVD) in TN patients with either relapsing-remitting MS (RRMS) or progressive MS.

METHODS

We retrospectively reviewed all TN patients who underwent MVDs at our institution from 2007 to 2020. Of the 1044 patients reviewed, 45 (4.3%) patients with MS were identified. Patient demographics, procedural characteristics, and post-operative pain and numbness scores were recorded and compared. Factors associated with pain recurrence were assessed using survival analyses and multivariate regressions.

RESULTS

Of the resulting 45 MS patients, 34 (75.6%) patients presented with the RRMS subtype, whereas 11 (24.4%) patients exhibited progressive MS. Using an adjusted multivariate ordinal regression, the subtype of MS was not significantly associated with the Barrow Neurological Institute (BNI) pain score at final follow-up. Using a Kaplan-Meier survival analysis and a multivariate Cox proportional hazards regression, respectively, RRMS was significantly associated with a shorter post-operative pain-free interval (p = 0.04) as well as a greater risk for pain recurrence (p = 0.02).

CONCLUSIONS

Although the degree of pain at final follow-up may not differ, RRMS patients are at increased risk for pain recurrence following MVD for TN. These results align with a growing understanding that neuroinflammation may play a significant role in TN pain.

The Comparison of General Characteristics and Early and Late Post-intervention Results in Patients With Trigeminal Neuralgia Secondary to Multiple Sclerosis and Idiopathic Trigeminal Neuralgia Treated With Radiofrequency Thermocoagulation

Aim The aim of this study was to investigate possible differences (in terms of demographic structure, disease history, complaints, clinical findings, early and late treatment outcomes, and complications) between patients with idiopathic trigeminal neuralgia (ITN) and trigeminal neuralgia (TN) secondary to multiple sclerosis (MS) who were admitted to our clinic and underwent radiofrequency (RF) thermocoagulation procedure. Materials and methods Patients who underwent percutaneous radiofrequency thermocoagulation with a diagnosis of trigeminal neuralgia by a single neurosurgeon in a single neurosurgery clinic between January 2005 and January 2020 were included in this study. Patients were divided into two groups: idiopathic trigeminal neuralgia and trigeminal neuralgia secondary to multiple sclerosis (MSTN) according to their diagnosis. In our study, 215 TN patients who underwent 286 procedures were included. These patients were categorized according to age, sex, involved side, pain localization, and pain history. Postoperative complications were determined after each intervention. The early and late results of all interventions were evaluated, and the results were compared between both groups. All results were statistically analyzed. Results Considering the age of the patients, the mean age of the idiopathic group was higher than the multiple sclerosis group (58.18>49.46). In terms of the side of pain, bilateral involvement was significantly more common in the MS secondary group (1.48%<30.77%). There was no significant difference between the early results of both groups. In terms of remission periods, the pain-free period in the MS secondary group was significantly shorter than in the idiopathic group (mean value in months, 30.87>23.81). Conclusion The radiofrequency thermocoagulation of the trigeminal nerve is a highly effective, low-complication, reproducible procedure for trigeminal neuralgia, but the search for ways to improve the efficacy of treatment in MS patients should continue.

Retrospective comparison of percutaneous balloon compression and radiofrequency-thermocoagulation in the management of trigeminal neuralgia

PURPOSE

To compare percutaneous balloon compression (PBC) and radiofrequency thermocoagulation (RFTC) for the treatment of trigeminal neuralgia.

METHODS

This was a retrospective single-center analysis of data from 230 patients with trigeminal neuralgia who underwent 202 PBC (46%) and 234 RFTC (54%) from 2002 to 2019. Comparison of demographic data and trigeminal neuralgia characteristics between procedures as well as assessment of 1) initial pain relief by an improved Barrow Neurological Institute (BNI) pain intensity scale of I-III; 2) recurrence-free survival of patients with a follow-up of at least 6 months by Kaplan-Meier analysis; 3) risk factors for failed initial pain relief and recurrence-free survival by regression analysis; and 4) complications and adverse events.

RESULTS

Initial pain relief was achieved in 353 (84.2%) procedures and showed no significant difference between PBC (83.7%) and RFTC (84.9%). Patients who suffered from multiple sclerosis (odds ratio 5.34) or had a higher preoperative BNI (odds ratio 2.01) showed a higher risk of not becoming pain free. Recurrence-free survival in 283 procedures was longer for PBC (44%) with 481 days compared to RFTC (56%) with 421 days (p=0.036) but without statistical significance. The only factors that showed a significant influence on longer recurrence-free survival rates were a postoperative BNI ≤ II (P=<0.0001) and a BNI facial numbness score ≥ 3 (p = 0.009). The complication rate of 22.2% as well as zero mortality showed no difference between the two procedures (p=0.162).

CONCLUSION

Both percutaneous interventions led to a comparable initial pain relief and recurrence-free survival with a low and comparable probability of complications. An individualized approach, considering the advantages and disadvantages of each intervention, should guide the decision-making process. Prospective comparative trials are urgently needed.

Sex-Specific Pain Outcomes Following Microvascular Decompression for Trigeminal Neuralgia

BACKGROUND

Trigeminal neuralgia (TN) is more prevalent among women. However, while microvascular decompression (MVD) is the most effective long-term surgical treatment for TN, it is unclear whether it is equally efficacious for men and women. We sought to characterize the relationship between sex and pain outcomes following MVD for TN.

METHODS

From 2007 to 2020, 938 unilateral TN patients were treated with MVD at our institution. Patient demographics, clinical characteristics, operative features, and pain outcomes were recorded. Differences between men and women were analyzed via t-test and chi-squared analyses. A multivariate ordinal regression was used to establish significant predictors of pain outcome. Differences in time to pain recurrence were assessed via Cox proportional hazards and Kaplan-Meier nonparametric survival analysis.

RESULTS

A majority (67%) of the 938 patients analyzed were female. Men and women presented with similar preoperative pain severity (P = 0.17). Female sex (P = 0.048) and younger age (P = 0.03) were independently associated with worsened Barrow Neurological Institute pain scores at 3-month follow-up on multivariate analysis. Women were also more likely to experience recurrence than men (P = 0.01), and time to recurrence was shorter among women (P = 0.02). Only female sex was independently associated with increased risk of postoperative pain recurrence on multivariate Cox proportional hazards regression (P = 0.01).

CONCLUSIONS

Female TN patients undergoing MVD had worse pain outcomes, more frequent pain recurrence, and shorter time to recurrence. Our results indicate a sex-specific dimorphism in response to MVD among TN patients.

Long term evaluation of a multidisciplinary trigeminal neuralgia service

Background

Trigeminal neuralgia is an episodic severe neuralgic pain and can be managed both medically and surgically. If possible, this should be directed by a Multidisciplinary Team (MDT) of specialised surgeons, physicians, dentists, psychologists and specialist nurses with access to all treatment modalities, which enables patients to make an informed decision about their future management.

Objective

The aim of this study was to review the outcomes of patients managed by an MDT clinic, in a single institute over an eleven-year period.

Methods

A prospective database was used to identify patients with trigeminal neuralgia or its variants who had attended a joint MDT clinic. The electronic notes were examined for demographics, onset and duration of trigeminal neuralgia, medications history, pain scores and details of surgical procedures if any by two independent assessors.

Results

Three hundred thirty-four patients attended the MDT between 2008–2019. Forty-nine of them had surgery before being referred to the service and were included but analysed as a subgroup. Of the remaining patients, 54% opted to have surgery following the MDT either immediately or at a later date. At the last reported visit 55% of patients who opted to have surgery were pain free and off medications, compared to 15.5% of medically managed patients. Surgical complications were mostly attributable to numbness and in the majority of cases this was temporary. All patients who were not pain free, had complications after surgery or opted to remain on medical therapy were followed up in a facial pain clinic which has access to pain physicians, clinical nurse specialists and a tailored pain management program. Regular patient related outcome measures are collected to evaluate outcomes.

Conclusion

An MDT clinic offers an opportunity for shared decision making with patients deciding on their personal care pathway which is valued by patients. Not all patients opt for surgery, and some continue to attend a multidisciplinary follow up program. Providing a full range of services including psychological support, improves outcomes.

Internal neurolysis: 'nerve combing' for trigeminal neuralgia without neurovascular conflict - early UK outcomes

INTRODUCTION

Internal neurolysis (INL) is a surgical procedure where trigeminal nerve fibres are separated between the pons and porus trigeminus to relieve trigeminal neuralgia (TN). We report pain and functional outcomes to evaluate its safety and efficacy.

MATERIALS AND METHODS

Prospective cohort of all patients undergoing retrosigmoid craniotomy and INL between 2015 and 2017 at University Hospital Southampton. Patients with type I (6) or type II (2) refractory TN and no clear neurovascular conflict were offered INL as an alternative to partial sensory rhizotomy. Barrow Pain Intensity Scale (BNI) and Brief Pain Inventory Facial scores (BPI-Facial) were assessed. Minimum follow-up was 2 years'.

RESULTS

Eight patients (7F:1M) underwent INL. Two had MS. Pre-operatively, all had severe pain (BNI grade V) and the median BPI-Facial score was 115 (range 79-123).. There were no unexpected complications. On last follow-up, six (75%) had no pain (BNI grade I), while two (25%) had recurred (at 5 and 27 months). Median BPI-Facial score for all patients on the last follow-up was 20 (range 18-91) reflecting dramatically improved quality of life and activities.

CONCLUSIONS

INL is a potentially safe and effective treatment for refractory TN. Long-term efficacy is unknown, but early results are promising.

The Long-Term Outcome of Radiofrequency Ablation in Multiple Sclerosis-Related Symptomatic Trigeminal Neuralgia

BACKGROUND

Radiofrequency lesioning (RFL) is used to surgically manage trigeminal neuralgia (TN) secondary to multiple sclerosis (MS). However, the long-term outcome of RFL has not been established.

OBJECTIVE

To investigate the long-term clinical outcome of RFL in MS-related TN (symptomatic trigeminal neuralgia [STN]).

METHODS

During a 23-yr period, institutional data were available for 51 patients with STN who underwent at least one RFL procedure to treat facial pain. Patient outcome was evaluated at a mean follow-up of 69 mo (95% confidence interval; range 52-86 mo). No pain with no medication (NPNM) was the primary long-term outcome measure.

RESULTS

After an initial RFL procedure, immediate pain relief was achieved in 50 patients (98%), and NPNM as assessed at 1, 3, and 6 yr was 86%, 52%, and 22%, respectively. At the last clinical visit after an initial RFL, 23 patients (45%) with pain recurrence underwent repeat RFL; NPNM at 1, 3, and 6 yr after a repeat RFL was 85%, 58%, and 32%, respectively. There was no difference in pain outcome after an initial and repeat RFL ( P = .77). Ten patients with pain recurrence underwent additional RFL procedures. Two patients developed mastication muscle weakness, one patient experienced a corneal abrasion, which resolved with early ophthalmological interventions, and one patient experienced bothersome numbness.

CONCLUSION

RFL achieves NPNM status in STN and can be repeated with similar efficacy.

[Neuropathic pain syndromes in patients with multiple sclerosis]

Among the numerous pain syndromes (PS) of various localizations and types, observed in patients with multiple sclerosis (MS), the greatest attention of researchers is attracted by neuropathic PS. Neuropathic PS are often present already in the early stage of MS, significantly reduce the quality of life, hinder the social adaptation of patients, poorly respond to therapy. Central neuropathic PS, which pathogenesis is closely related with plaques in the central nervous system, are most common in patients with MS. Diagnostics of neuropathic PS in MS is based mainly on typical clinical symptoms; MRI and neurophysiological methods data are of secondary importance. This review focuses on modern concepts of three main neuropathic PS in MS: ongoing extremity pain, trigeminal neuralgia and Lhermitte's sign. Clinical symptoms of neuropathic PS, current ideas about their pathogenetic mechanisms, MRI and neurophysiological techniques data and the existing approaches to conservative therapy and surgical treatment based on randomized trials data are presented.

Percutaneous Radiofrequency Thermocoagulation in Trigeminal Neuralgia : Analysis of Early and Late Outcomes of 156 Cases and 209 Interventions

Objective

Trigeminal neuralgia is one of the most common causes of facial pain. Our aim is to investigate the efficacy and borders of percutaneous radiofrequency thermocoagulation in the treatment of trigeminal neuralgia.

Methods

Between May 2007 and April 2017, 156 patients with trigeminal neuralgia were treated with radiofrequency thermocoagulation. These 156 patients underwent 209 procedures. In our study, we investigated the early and late results of percutaneous radiofrequency thermocoagulation under guiding fluoroscopic imaging in the treatment of trigeminal neuralgia. Barrow Neurological Institute (BNI) pain scale was used for grading the early results. In addition, Kaplan-Meier survival analysis was used to assess long-term outcomes. Of the 156 patients who underwent radiofrequency thermocoagulation for trigeminal neuralgia, 45 had additional disease. Patients with this condition were evaluated with their comorbidities. Early and late results were compared with those without comorbidity.

Results

In 193 of 209 interventions BNI pain scale I to III results were obtained. Out of the 193 successful operation 136 patients (65.07%) were discharged as BNI I, 14 (6.70%) as BNI II, 43 (20.58%) as BNI III. Sixteen patients (7.65%) remained uncontrolled (BNI IV and V). While the treatment results of trigeminal neuralgia patients with comorbidity seem more successful in the early period, this difference was not observed in follow-up examinations.

Conclusion

Finally, we concluded that percutaneous radiofrequency thermocoagulation of the Gasserian ganglion is a safe and effective method in the treatment of trigeminal neuralgia. However, over time, the effectiveness of the treatment decreases. Neverthless, the reapprability of this intervention gives it a distinct advantage.

The journeys of patients with trigeminal neuralgia on a background of multiple sclerosis

Aim: Multiple sclerosis (MS) is well recognized as a secondary cause for trigeminal neuralgia (TN). In this case series, we detail the management of all the patients with TN and MS (pwTNMS) presenting to a specialist unit. Materials & methods: A prospective patient database was used to extract key clinical data on pharmacological, psychometric and surgical management of 20 pwTNMS. Results: 65% of pwTNMS underwent surgical interventions for management of their pain.12/20 achieved remission periods, through surgery and/or medication. Significant improvement was noted on the global impression of change illustrated by a p < 0.001. Conclusion: pwTNMS require a multifaceted approach combining polypharmacy, surgical interventions and psychological support. Developing self-management skills is crucial if patients are to live well with pain.

Results of three or more Gamma Knife radiosurgery procedures for recurrent trigeminal neuralgia

OBJECTIVE

Gamma Knife radiosurgery (GKRS) is an established surgical option for the treatment of trigeminal neuralgia (TN), particularly for high-risk surgical candidates and those with recurrent pain. However, outcomes after three or more GKRS treatments have rarely been reported. Herein, the authors reviewed outcomes among patients who had undergone three or more GKRS procedures for recurrent TN.

METHODS

The authors conducted a multicenter retrospective analysis of patients who had undergone at least three GKRS treatments for TN between July 1997 and April 2019 at two different institutions. Clinical characteristics, radiosurgical dosimetry and technique, pain outcomes, and complications were reviewed. Pain outcomes were scored on the Barrow Neurological Institute (BNI) scale, including time to pain relief (BNI score ≤ III) and recurrence (BNI score > III).

RESULTS

A total of 30 patients were identified, including 16 women and 14 men. Median pain duration prior to the first GKRS treatment was 10 years. Three patients (10%) had multiple sclerosis. Time to pain relief was longer after the third treatment (p = 0.0003), whereas time to pain recurrence was similar across each of the successive treatments (p = 0.842). Complete or partial pain relief was achieved in 93.1% of patients after the third treatment. The maximum pain relief achieved after the third treatment was significantly better among patients with no prior percutaneous procedures (p = 0.0111) and patients with shorter durations of pain before initiation of GKRS therapy (p = 0.0449). New or progressive facial sensory dysfunction occurred in 29% of patients after the third GKRS treatment and was reported as bothersome in 14%. One patient developed facial twitching, while another experienced persistent lacrimation. No statistically significant predictors of adverse effects following the third treatment were found. Over a median of 39 months of follow-up, 77% of patients maintained complete or partial pain relief. Three patients underwent a fourth GKRS treatment, including one who ultimately received five treatments; all of them reported sustained pain relief at the extended follow-up.

CONCLUSIONS

The authors describe the largest series to date of patients undergoing three or more GKRS treatments for refractory TN. A third treatment may produce outcomes similar to those of the first two treatments in terms of long-term pain relief, recurrence, and adverse effects.

A multicenter survey on access to care in Multiple Sclerosis-related trigeminal neuralgia

The prevalence of trigeminal neuralgia (TN) in patients with Multiple Sclerosis (MS) is higher than in the general population and its management can be particularly challenging due to a number of reasons including high recurrence rates, lack of MS-specific treatment guidelines and uncertainties about pain pathophysiology. Aim of this cross-sectional, multicentre survey was to gather information on the current treatment modalities and options of MS-related TN across 23 Italian MS centres. Initial medical management (carbamazepine or oxcarbazepine) of MS-related TN was fairly homogeneous throughout Italian centres. The most commonly available surgical procedure was microvascular decompression, but the frequency and types of surgical procedures available locally differed considerably throughout MS centers, and were unavailable in one quarter of them. This survey reveals some of the issues that could hamper an optimal patient management and underlines the need for a consensus on MS-related TN to support health-care professionals in their approach to this challenging condition and to facilitate the development of local guidelines aimed at ensuring equity in access to care and treatment optimization.

Gamma Knife Radiosurgery for the Treatment of Trigeminal Neuralgia in Patients with Multiple Sclerosis: A Single-Center Retrospective Study and Literature Review

OBJECTIVE

Trigeminal neuralgia (TN) in patients with multiple sclerosis (MS) is a challenging condition to manage that is treated with Gamma Knife radiosurgery (GKRS). The aim of this report is to assess the safety, efficacy, and durability of GKRS for the treatment of TN in patients with MS. Our findings are compared with those of the existing literature and discussed.

METHODS

We retrospectively reviewed all patients at our institution who underwent GKRS for the treatment of TN secondary to MS and had 1 or more years of follow-up. Preoperative and postoperative pain intensities and facial numbness were evaluated with the Barrow Neurological Institute scores. Durability of successful pain relief was statistically evaluated with Kaplan-Meier analysis. The prognostic role of perioperative factors was investigated and analyzed using Cox proportional hazards regression.

RESULTS

There were 29 patients with MS-TN who underwent GKRS at our institution. Two patients underwent bilateral treatment. Four patients underwent repeat GKRS for pain recurrence. The median period of follow-up assessment was 33 months. Rates of reasonable pain reduction at 1, 3, and 5 years were 70%, 57%, and 57% respectively. All patients who underwent repeat GKRS had durable pain reduction. No prognostic factor for successful pain reduction was found.

CONCLUSIONS

Our study shows that GKRS for the treatment of TN secondary to MS is a safe and effective procedure in controlling pain in the short term but often fails to provide long-term pain control. GKRS can be safely repeated to prolong the time of pain reduction.

Trigeminal neuralgia: An overview from pathophysiology to pharmacological treatments

The trigeminal nerve (V) is the fifth and largest of all cranial nerves, and it is responsible for detecting sensory stimuli that arise from the craniofacial area. The nerve is divided into three branches: ophthalmic (V1), maxillary (V2), and mandibular (V3); their cell bodies are located in the trigeminal ganglia and they make connections with second-order neurons in the trigeminal brainstem sensory nuclear complex. Ascending projections via the trigeminothalamic tract transmit information to the thalamus and other brain regions responsible for interpreting sensory information. One of the most common forms of craniofacial pain is trigeminal neuralgia. Trigeminal neuralgia is characterized by sudden, brief, and excruciating facial pain attacks in one or more of the V branches, leading to a severe reduction in the quality of life of affected patients. Trigeminal neuralgia etiology can be classified into idiopathic, classic, and secondary. Classic trigeminal neuralgia is associated with neurovascular compression in the trigeminal root entry zone, which can lead to demyelination and a dysregulation of voltage-gated sodium channel expression in the membrane. These alterations may be responsible for pain attacks in trigeminal neuralgia patients. The antiepileptic drugs carbamazepine and oxcarbazepine are the first-line pharmacological treatment for trigeminal neuralgia. Their mechanism of action is a modulation of voltage-gated sodium channels, leading to a decrease in neuronal activity. Although carbamazepine and oxcarbazepine are the first-line treatment, other drugs may be useful for pain control in trigeminal neuralgia. Among them, the anticonvulsants gabapentin, pregabalin, lamotrigine and phenytoin, baclofen, and botulinum toxin type A can be coadministered with carbamazepine or oxcarbazepine for a synergistic approach. New pharmacological alternatives are being explored such as the active metabolite of oxcarbazepine, eslicarbazepine, and the new Nav1.7 blocker vixotrigine. The pharmacological profiles of these drugs are addressed in this review.

Neurovascular contact plays no role in trigeminal neuralgia secondary to multiple sclerosis

INTRODUCTION

A demyelinating plaque and neurovascular contact with morphological changes have both been suggested to contribute to the etiology of trigeminal neuralgia secondary to multiple sclerosis (TN-MS). The aim of this study was to confirm or refute whether neurovascular contact with morphological changes is involved in the etiology of TN-MS.

METHODS

We prospectively enrolled consecutive TN-MS patients from the Danish Headache Center. Clinical characteristics were collected systematically. MRI scans were done using a 3.0 Tesla imager and were evaluated by the same experienced blinded neuroradiologist.

RESULTS

Sixty-three patients were included. Fifty-four patients were included in the MRI analysis. There was a low prevalence of neurovascular contact with morphological changes on both the symptomatic side (6 (14%)) and the asymptomatic side (4 (9%)), p = 0.157. Demyelinating brainstem plaques along the trigeminal afferents were more prevalent on the symptomatic side compared to the asymptomatic side (31 (58%) vs. 12 (22%), p < 0.001). A demyelinating plaque was highly associated with the symptomatic side (odds ratio = 10.6, p = 0.002).

CONCLUSION

The primary cause of TN-MS is demyelination along the intrapontine trigeminal afferents. As opposed to classical trigeminal neuralgia, neurovascular contact does not play a role in the etiology of TN-MS. Microvascular decompression should generally not be offered to patients with TN-MS.The study was registered at ClinicalTrials.gov (number NCT04371575).

Operative findings and outcome of microvascular decompression/adhesiolysis for trigeminal neuralgia in multiple sclerosis without demyelinating brain stem lesions

OBJECTIVE

Trigeminal neuralgia (TN) in multiple sclerosis (MS) poses several challenges for treatment. Although these patients often have typical attacks, they may not be considered as candidates for microvascular decompression (MVD). Here we report on surgical findings and long term follow-up of MVD/ adhesiolysis in a series of patients with multiple sclerosis but without demyelinating brain stem lesions.

METHODS

Fifteen patients with MS-related TN underwent MVD/ adhesiolysis. Demyelinating brain stem lesions were excluded radiologically. Outcome of the intervention was assessed according to the Barrow Neurological Institute (BNI) pain intensity score at 3, 12, 24 months follow-up and at the last available follow-up (mean 88.2 months, range 38-146).

RESULTS

All 15 patients benefited from MVD/adhesiolysis and were pain free on the first day of surgery. Intraoperative findings included arterial contact in 7/15 (47 %) patients, venous contact in 9/15 (60 %), and prominent arachnoid thickening in 12/15 (80 %). The distribution of the BNI pain intensity scores showed marked improvement at all follow-up evaluations. Five patients underwent repeat MVD/adhesiolysis for pain recurrence at a mean of 43 months after the first surgery. Long term evaluation at the last available follow-up demonstrated favorable outcome in 13/15 patients (BNI I-IIIa) (87 %), while 2/15 patients had limited benefit (BNI IV).

CONCLUSIONS

MS-related TN in patients without demyelinating brain stem lesions may be related either to vascular conflicts or to focal arachnoiditis at the trigeminal nerve entry zone. MVD/ adhesiolysis may be considered as a useful treatment option in this subgroup of patients with regard to long term outcome.

Craniofacial neuralgias

While non-headache, non-oral craniofacial neuralgia is relatively rare in incidence and prevalence, it can result in debilitating pain. Understanding the relevant anatomy of peripheral branches of nerves, natural history, clinical presentation, and management strategies will help the clinician better diagnose and treat craniofacial neuralgias. This article will review the nerves responsible for neuropathic pain in periorbital, periauricular, and occipital regions, distinct from idiopathic trigeminal neuralgia. The infratrochlear, supratrochlear, supraorbital, lacrimal, and infraorbital nerves mediate periorbital neuralgia. Periauricular neuralgia may involve the auriculotemporal nerve, the great auricular nerve, and the nervus intermedius. The greater occipital nerve, lesser occipital nerve, and third occipital nerve transmit occipital neuralgias. A wide range of treatment options exist, from modalities to surgery, and the evidence behind each is reviewed.

Comparison of Stereotactic Radiosurgery and Radiofrequency Ablation for Trigeminal Neuralgia in Multiple Sclerosis Patients

<b><i>Background:</i></b> The optimal treatment for medically refractory trigeminal neuralgia in multiple sclerosis (MS-TN) patients is unknown. <b><i>Objective:</i></b> To compare treatment outcomes between stereotactic radiosurgery (SRS) and radiofrequency ablation (RFA). <b><i>Methods:</i></b> We performed a retrospective study of MS-TN patients treated with SRS or RFA between 2002 and 2019. Outcomes included degree of pain relief, pain recurrence, and sensory changes, segregated based on initial treatment, final treatment following retreatment with the same modality, and crossover patients. <b><i>Results:</i></b> Sixty surgical cases for 42 MS-TN patients were reviewed. Initial pain freedom outcomes and rates of retreatment were similar (SRS: 30%; RFA: 42%). RFA resulted in faster onset of pain freedom (RFA: &#x3c;1 week; SRS: 15 weeks; <i>p</i> &#x3c; 0.001). SRS patients with pain relief had longer intervals to pain recurrence at 2 years (<i>p</i> = 0.044). Final treatment outcomes favored RFA for pain freedom/off-medication outcomes (RFA: 44%; SRS: 11%; <i>p</i> = 0.031), though RFA resulted in more paresthesia (RFA: 81%; SRS: 39%; <i>p</i> = 0.012). Both provided at least 80% of adequate pain relief. Crossover patients did not have improved pain relief. <b><i>Conclusions:</i></b> SRS and RFA are both valid surgical options for MS-TN. Discussion with providers will need to balance patient preference with their unique treatment characteristics.

Percutaneous glycerol rhizotomy for trigeminal neuralgia in patients with multiple sclerosis: a long-term retrospective cohort study

OBJECTIVE

The prevalence of trigeminal neuralgia (TN) in patients with multiple sclerosis (MS-TN) is higher than in the general population (idiopathic TN [ITN]). Glycerol rhizotomy (GR) is a percutaneous lesioning surgery commonly performed for the treatment of medically refractory TN. While treatment for acute pain relief is excellent, long-term pain relief is poorer. The object of this study was to assess the efficacy of percutaneous retrogasserian GR for the treatment of MS-TN versus ITN.

METHODS

A retrospective chart review was performed, identifying 219 patients who had undergone 401 GR procedures from 1983 to 2018 at a single academic institution. All patients were diagnosed with medically refractory MS-TN (182 procedures) or ITN (219 procedures). The primary outcome measures of interest were immediate pain relief and time to pain recurrence following initial and repeat GR procedures. Secondary outcomes included medication usage and presence of periprocedural hypesthesia.

RESULTS

The initial pain-free response rate was similar between groups (p = 0.726): MS-TN initial GR 89.6%; MS-TN repeat GR 91.9%; ITN initial GR 89.6%; ITN repeat GR 87.0%. The median time to recurrence after initial GR was similar between MS-TN (2.7 ± 1.3 years) and ITN (2.1 ± 0.6 years) patients (p = 0.87). However, there was a statistically significant difference in the time to recurrence after repeat GR between MS-TN (2.3 ± 0.5 years) and ITN patients (1.2 ± 0.2 years; p < 0.05). The presence of periprocedural hypesthesia was highly predictive of pain-free survival (p < 0.01).

CONCLUSIONS

Patients with MS-TN achieve meaningful pain relief following GR, with an efficacy comparable to that following GR in patients with ITN. Initial and subsequent GR procedures are equally efficacious.

Microvascular decompression in patients with trigeminal neuralgia and multiple sclerosis: results and analysis of possible prognostic factors

We evaluated the results of microvascular decompression (MVD) in patients with trigeminal neuralgia (TN) and multiple sclerosis (MS) and we studied the role of several clinical and surgical factors as possible prognosticators of good outcome. To do this we performed, to our knowledge, the first literature review with a pooled analysis of data. A PubMed search of literature was conducted using the following terms: "microvascular decompression", "trigeminal neuralgia" and "multiple sclerosis". We screened 64 articles. Of them, 7 studies were eligible for this review. As outcome indicators we used the acute pain relief (APR) and the recurrence of pain. An APR was obtained in 71.42% and a recurrence of pain was reported in 26.00% of cases, respectively. At univariate analysis, younger age at surgery (p = 0.0419) and performing MVD as the first treatment (p = 0.0384) were associated to a higher probability of APR. The evidence of an MRI brainstem lesion related to the TN (p = 0.0482) was associated to a lower probability to obtain an APR after MVD. None of the evaluated factors affect the probability of recurrence of pain. At multivariate analysis the evidence of a brainstem MRI lesion related to the TN emerged as a negative prognosticator of APR (p = 0.0169). Our literature pooled analysis showed that MVD is effective in treating patients with MS-related TN. The evidence on MRI of a demyelinating plaque related to the TN is associated with a worse response to MVD. These data could suggest that MVD would be indicated mainly in patients without brainstem MRI lesions.

Relationship Between Arterial Blood Pressure During Trigeminal Nerve Combing and Surgical Outcome in Patients with Trigeminal Neuralgia

INTRODUCTION

Changes in blood pressure during trigeminal combing have been discussed in recent years. In this study, a retrospective analysis of patients with trigeminal neuralgia (TN) requiring microvascular decompression (MVD) with nerve combing was carried out to investigate fluctuation in arterial blood pressure during trigeminal nerve combing and its surgical effect and corresponding pathogenesis.

METHODS

A total of 70 cases of MVD with nerve combing performed during the treatment of primary TN patients were selected between January 2017 and January 2018 at Peking University People's Hospital. The degree of pain and prognosis of the patients were evaluated according to the visual analog scale. Postoperative facial numbness of the 2 groups were assessed by the Barrow Neurological Institute facial numbness score. Arterial blood pressure changes before and while combing the trigeminal nerve during MVD were dynamically monitored, and the patients were divided into responders and nonresponders. Total adrenaline (AD), norepinephrine (NE), and dopamine values were measured before and during trigeminal nerve combing.

RESULTS

Increased arterial blood pressure during the combing of the trigeminal nerve in MVD had a significant correlation with the prognosis of patients, with patients with higher arterial blood pressure having a better prognosis (P < 0.05). In the increased arterial blood pressure patients, precombing total AD and NE means were dramatically improved (P < 0.05).

CONCLUSIONS

This study shows that changes in arterial blood pressure during trigeminal nerve combing in MVD were correlated with the prognosis of patients. Further research is necessary to clarify the mechanism of increased arterial blood pressure.

Management of Multiple Sclerosis Symptoms and Comorbidities

PURPOSE OF REVIEW

This article discusses the prevalence, identification, and management of multiple sclerosis (MS)-related symptoms and associated comorbidities, including complications that can present at all stages of the disease course.

RECENT FINDINGS

The impact of comorbidities on the outcome of MS is increasingly recognized. This presents an opportunity to impact the course and outcome of MS by identifying and treating associated comorbidities that may be more amenable to treatment than the underlying inflammatory and neurodegenerative disease. The identification of MS-related symptoms and comorbidities is facilitated by brief screening tools, ideally completed by the patient and automatically entered into the patient record, with therapeutic suggestions for the provider. The development of free, open-source screening tools that can be integrated with electronic health records provides opportunities to identify and treat MS-related symptoms and comorbidities at an early stage.

SUMMARY

Identification and management of MS-related symptoms and comorbidities can lead to improved outcomes, improved quality of life, and reduced disease activity. The use of brief patient-reported screening tools at or before the point of care can facilitate identification of symptoms and comorbidities that may be amenable to intervention.

Microvascular Decompression for Trigeminal Neuralgia in Patients with Multiple Sclerosis: Predictors of Treatment Success

BACKGROUND

Microvascular decompression (MVD) is highly effective in managing the neuropathic facial pain of trigeminal neuralgia (TN). Its utility in patients with TN and concurrent multiple sclerosis (MS) has been a subject of debate. The goal of this study was to identify demographic and perioperative variables associated with favorable outcome after MVD over the past 20 years in patients from our institution.

METHODS

A retrospective analysis of our cohort of 33 patients diagnosed with MS and TN who underwent MVD between 1997 and 2017 to treat neuropathic facial pain was performed. Perioperative variables included MS disease burden, findings on preoperative magnetic resonance imaging (MRI), TN pain severity, and the presence of intraoperative neurovascular compression. MS disease burden was quantified using the Expanded Disability Status Scale. Preoperative and postoperative pain severity was quantified using the Barrow Neurological Institute (BNI) pain severity scale.

RESULTS

A total of 33 patients with TN and MS were treated with MVD at our institution (out of the 632 total MVDs performed) between 1997 and 2017. Twenty-two patients (67%) maintained a reduction in pain at a mean follow-up of 53.5 months. Higher preoperative BNI pain intensity score was associated with unfavorable outcome after MVD (P = 0.006). No associations were identified between MS disease burden, presence of neurovascular compression or pontine demyelinating plaques on MRI, or intraoperative findings of neurovascular compression and treatment outcomes.

CONCLUSIONS

MVD is a reasonable treatment option for patients with TN and MS, although the rate of freedom from pain is lower than that for the general TN population. Preoperative pain severity may be a predictor of treatment success.

Pain Management in Multiple Sclerosis: a Review of Available Treatment Options

PURPOSE OF REVIEW

Multiple Sclerosis (MS) is a chronic autoimmune disease with no curative treatment available. While recent years have ushered in many effective new disease-modifying therapies for MS, they have not obviated the need for symptomatic treatments for MS-related pain. In this review, we discuss available approaches to control pain, which is one of the most common complaints MS patients have.

RECENT FINDINGS

The most recent research in this topic is directed towards non-pharmacologic interventions including water exercises, yoga and cannabis. More trials are being conducted on neuromodulation for MS-related neuropathic pain, including transcutaneous electrical nerve stimulation (TENS) and transcranial direct current stimulation (tDCS). Pain control for MS patients is challenging, considering the progressive and relapsing remitting nature of the disease, however, it is a very important aspect of it's management, as it improves mobility, exercise tolerance, concomitant depression and overall quality of life. Future research should focus on the use of neuromodulation in controlling MS pain.

Endoscopic Infraorbital Microdissection for Localized V2 Trigeminal Neuralgia

Trigeminal neuralgia is a chronic and debilitating syndrome characterized by short paroxysms of lancinating facial pain. Patients may be medically managed; however, in cases of medically refractory trigeminal neuralgia, surgical management is often required. Our objective was to present and describe a technique for endoscopic microdissection of the infraorbital nerve, a peripheral method of management for refractory V2 trigeminal neuralgia in patients without evidence of neurovascular compression. The technique is designed to spare sensation in unaffected portions of the V2 distribution. We present 2 patients with medically refractory V2 trigeminal neuralgia localized to the lateral midface who underwent infraorbital microdissection. After first confirming that there was no neurovascular compression on imaging in these patients, we administered infraorbital bupivacaine injections to localize the symptomatic nerve. The nerve was then accessed via a 1.5-cm buccogingival incision, and the connective tissue sheath was incised. The nerve fascicles were bluntly separated, and the symptomatic branches were cauterized with fine-tipped monopolar cautery. Both patients reported complete resolution of their pain postoperatively and were pain free at last follow-up. They reported some hypoesthesia in the lateral face; however, they retained some sensation in the medial upper lip, midface, and nose. Infraorbital microdissection is a safe and effective technique for symptomatic management of V2 trigeminal neuralgia while sparing sensation in asymptomatic portions of the dermatome.

Minimally invasive trigeminal ablation in patients with refractory trigeminal neuralgia who are ineligible for intracranial intervention

We describe the use of minimally invasive trigeminal ablation, an endoscopic ablative technique to treat trigeminal neuralgia in patients who are traditionally poor surgical candidates. We present 4 patients who presented with refractory unilateral trigeminal neuralgia. Three of the patients had previously failed stereotactic radiosurgery and three of them have multiple sclerosis. Due either to lack of neurovascular compression, minimally invasive trigeminal ablation was offered. Intraoperatively, an incision is made along the buccal mucosa or mid-brow and the tissue is endoscopically dissected in a plane towards the symptomatic nerve. Once isolated, the epineurium is partially ablated with thermocautery and the tissue surrounding the nerve is decompressed. All patients reported resolution of their pain post-operatively and were pain free at last follow up. Two patients had mild hypesthesia over the ablated nerve territory. Minimally invasive trigeminal ablation is a safe and effective technique for symptomatic control of trigeminal neuralgia. The efficacy, low risk, and relative ease of the procedure makes it ideal for use in patients who are refractory to medical management and have no neurovascular compression, are unable to tolerate traditional surgery or have failed other therapies.

Advances in the Understanding and Management of Chronic Pain in Multiple Sclerosis: a Comprehensive Review

PURPOSE OF REVIEW

Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system that can lead to severe physical, cognitive, and neurological deficits that often manifest in young adults. Central neuropathic pain is a common presenting symptom, often prompting patients to seek treatment with opioids, NSAIDS, antiepileptics, and antidepressants despite minimal effectiveness and alarming side-effect profiles. Additionally, spasticity occurs in more than 80% of MS patients and is an important consideration for further study in treatment.

RECENT FINDINGS

Related to inconsistencies in pain presentation and clinical reporting, current studies continue to investigate clinical patient presentation to define chronic pain characteristics to optimize treatment plans. Although often neuropathic in origin, the complex nature of such pain necessitates a multimodal approach for adequate treatment. While psychiatric comorbidities typically remain unchanged in their severity over time, physical conditions may lead to worsening chronic pain long-term, often due to decreased quality of life. The prevalence of neuropathic pain is ~ 86% in patients with multiple sclerosis and most commonly presents as extremity pain, trigeminal neuralgia, back pain, or headaches. As MS symptoms are frequently unremitting and poorly responsive to conventional medical management, recent attention has been given to novel interventions for management of pain. Among these, medicinal cannabis therapy, targeted physical therapy, and neuromodulation offer promising results. In this review, we provide a comprehensive update of the current perspective of MS pathophysiology, symptomatology, and treatment.

Trigeminal neuralgia: Comparison of characteristics and impact in patients with or without multiple sclerosis

OBJECTIVES

The commonest secondary cause for trigeminal neuralgia (TN) is multiple sclerosis (MS) and little is known about this group of patients in terms of their presentation and treatments. We compared patients with TN and MS (pwTNMS) with a cohort of patients with primary TN, who had been referred to the same specialist unit, both in terms of characteristics and impact on quality of life at the time of their first assessment.

METHODS

Using a prospective patient database we extracted key clinical data and results from psychometrically tested questionnaires of 26 pwTNMS and compared them to an age and gender-matched set of 68 patients with primary TN.

RESULTS

Our findings suggest that pwTNMS exhibit a more severe clinical phenotype than primary TN. Prior to referral, pwTNMS are more likely to have used more healthcare services and undergone more neurosurgical interventions. Strikingly, pwTNMS exhibit reduced lengths and duration of remission periods and fewer identifiable triggers. Furthermore, pwTNMS report significant impact on quality of life comparable to those in primary TN, scoring highly in measures of anxiety, depression, and catastrophizing, but also report greater sleep disturbance, and overall interference in activities of daily living.

CONCLUSIONS

pwTNMS have a more intractable TN, one which may necessitate a more complex approach to treatment, earlier referral to secondary care and an extensive assessment of mental health. Quality of life in pwTNMS is severely affected by both their MS and their TN, suggesting management should occur in specialist centres with access to a multidisciplinary team.

The Effectiveness of Percutaneous Balloon Compression, Thermocoagulation, and Glycerol Rhizolysis for Trigeminal Neuralgia in Multiple Sclerosis

BACKGROUND

Balloon compression (BC), thermocoagulation (TC), and glycerol rhizolysis (GR) are percutaneous surgical options for trigeminal neuralgia (TN). Whether the outcomes of these procedures in multiple sclerosis -related TN (MS-TN) are as effective as in idiopathic TN (ITN) is unknown.

OBJECTIVE

To retrospectively compare pain relief, complications, and durability achieved by these 3 types of procedures in MS-TN and ITN.

METHODS

Two hundred and four patients with typical TN were treated percutaneously: 33 had MS-TN (64 procedures) and 171 had ITN (329 procedures). All were performed by 1 of 2 neurosurgeons; interviews enabled long-term data to be gathered by an independent observer.

RESULTS

MS-TN patients (53.1%) had Barrow Neurological Institute pain scores of I or II after a percutaneous procedure, compared with 59.3% in the ITN cohort; there was no difference in initial relief between the 2 groups overall (P = .52). There was a trend toward fewer complications in MS-TN compared with ITN (23.4% vs 33.7%, respectively; P = .058). Kaplan–Meier analysis demonstrated no difference in durability of relief in MS-TN (median 23.0 mo) compared with ITN overall (median 24.0 mo; P = .75). Subgroup analysis demonstrated longer relief from BC and TC compared with GR in MS-TN (P = .013). Multivariate analysis confirmed that although the presence of MS does not predict durability of outcome, postoperative numbness (P = .0046) and undergoing a repeat procedure (P = .037) were significant predictors.

CONCLUSION

BC and TC are safe and effective in MS-TN. Postoperative numbness is the strongest prognostic factor in MS-TN.

Current and Innovative Pharmacological Options to Treat Typical and Atypical Trigeminal Neuralgia

Trigeminal neuralgia is a representative neuropathic facial pain condition, characterised by unilateral paroxysmal pain in the distribution territory of one or more divisions of the trigeminal nerve, triggered by innocuous stimuli. A subgroup of patients with trigeminal neuralgia [TN (previously defined as atypical TN)] also suffer from concomitant continuous pain, i.e. a background pain between the paroxysmal attacks. The aim of this review is to provide current, evidence-based, knowledge about the pharmacological treatment of typical and atypical TN, with a specific focus on drugs in development. We searched for relevant papers within PubMed, EMBASE, the Cochrane Database of Systematic Reviews and the Clinical Trials database (ClinicalTrials.gov), taking into account publications up to February 2018. Two authors independently selected studies for inclusions, data extraction, and bias assessment. Carbamazepine and oxcarbazepine are the first-choice drugs for paroxysmal pain. When sodium channel blockers cannot reach full dosage because of side effects, an add-on treatment with lamotrigine or baclofen should be considered. In patients with atypical TN, both gabapentin and antidepressants are expected to be efficacious and should be tried as an add-on to oxcarbazepine or carbamazepine. Although carbamazepine and oxcarbazepine are effective in virtually the totality of patients, they are responsible for side effects causing withdrawal from treatment in an important percentage of cases. A new, better tolerated, Nav1.7 selective state-dependent, sodium channel blocker (vixotrigine) is under development. Future trials testing the effect of combination therapy in patients with TN are needed, especially in patients with concomitant continuous pain and in TN secondary to multiple sclerosis.