Real-world effectiveness and tolerability of carbamazepine and oxcarbazepine in 354 patients with trigeminal neuralgia

Repeat percutaneous rhizotomy for trigeminal neuralgia is not associated with an increased risk of postoperative complications

BACKGROUND AND OBJECTIVES

Patients undergoing percutaneous rhizotomy for trigeminal neuralgia (TN) may require several procedures to manage their pain. However, it is not fully understood whether repeat procedures influence postoperative complication rates.

METHODS

We retrospectively reviewed patients undergoing rhizotomy at our institution from 2011 to 2022. Patients were included only if they had no history of prior interventions including microvascular decompression (MVD) or radiosurgery. We collected baseline patient information, pain characteristics, and postoperative complications for each patient. Patients were dichotomized into those undergoing primary rhizotomy versus those undergoing a repeat rhizotomy. Potential drivers of postoperative complications were included in a multivariate logistic regression model.

RESULTS

Of the 1904 cases reviewed, 965 met our inclusion criteria. 392 patients underwent primary rhizotomy, and 573 patients underwent repeat rhizotomies. The repeat rhizotomy group was significantly older, p<0.001. Patients in the repeat rhizotomy group expressed higher frequencies of bilateral pain, p=0.01. Patients in the repeat rhizotomy group demonstrated a significantly higher rate of preoperative numbness and postoperative numbness, p<0.001. There were no significant differences in any of the considered complications between the single rhizotomy and repeat rhizotomy groups. On multivariate logistic regression, repeat rhizotomy did not predict an increased risk of any postoperative complications, p=0.14.

CONCLUSIONS

Patients undergoing repeat rhizotomy may be at risk of postoperative numbness but are not at increased risk for postoperative complications. These results are of use to patients who are poor surgical candidates, and thus may require multiple rhizotomies to effectively manage their pain over time.

A retrospective comparative case series of efficacy and safety of radiofrequency thermocoagulation versus drug therapy in patients with trigeminal neuralgia: A clinical case report

BACKGROUND

The trigeminal neuralgia (TN) is characterized by a unilateral, episodic, electric shock-like pain in the distribution of the trigeminal nerve. Both drug therapy and radiofrequency thermocoagulation (RT) are used to treat TN.

OBJECTIVE

To compare the efficacy and safety of RT and drug therapy in patients with TN.

METHODS

Between October 2020 and December 2022, 62 patients with TN were allocated to undergo TN treatment (group A) or drug therapy (group B). In group A, 30 patients received RT treatment, whereas 32 patients in group B receive drug treatment. Pain relief, clinical outcomes, and adverse events in both groups were evaluated.

RESULTS

And significantly greater reduction in Visual Analogue Scale scores was noted in group A than in group B in the initial 2-week period (P < .05). The excellent rate was 93.3% (28/30) in group A, whereas it was 68.8% (22/32) in group B during the initial 2-week period (P < .05). A total of 62 patients were followed up at least 12 months, with a mean follow-up time of 14.5 months. But there were no statistically significant differences between the 2 groups at the final follow-up. A total of 24 patients had facial numbness in group A. In contrast, ten patients in group B complained of discomfort including sedation, dizziness, nausea, vomiting. During the follow-up period, 4 patients in group A and 6 patients in group B experienced recurrent pain.

CONCLUSION

RT is a safety and effective treatment for patients with classic TN, providing more benefits of quicker pain relief and higher patient's satisfaction, compared with traditional drug therapy.

Topiramate inhibits adjuvant-induced chronic orofacial inflammatory allodynia in the rat

Chronic orofacial pain disorders are common debilitating conditions, affecting the trigeminal system. Its underlying pathophysiological mechanisms are still unclear and the therapy is often unsatisfactory, therefore, preclinical models are crucial to identify the key mediators and novel treatment options. Complete Freund's adjuvant (CFA)-induced orofacial inflammatory allodynia/hyperalgesia is commonly used in rodents, but it has not been validated with currently used drugs. Here we tested the effects of the adjuvant analgesic/antiepileptic voltage-gated Na+ channel blocker complex mechanism of action topiramate in comparison with the gold standard antimigraine serotonin 5-HT1B/D receptor agonist sumatriptan in this model. CFA was injected subcutaneously into the right whisker pad of male Sprague-Dawley rats (250-300 g), then mechanonociceptive threshold values were investigated with von Frey filaments (3, 5, and 7 days after CFA injection). Effects of topiramate (30 mg/kg per os) and sumatriptan (1 mg/kg subcutaneous) on the adjuvant-induced chronic inflammatory orofacial allodynia were investigated 60, 120, and 180 min after the treatments each day. To determine the optimal concentration for drug effect analysis, we tested the effects of two different CFA-concentrations (1 and 0.5 mg/mL) on mechanonociceptive thresholds. Both concentrations of CFA induced a chronic orofacial allodynia in 60% of all rats. Although, higher CFA concentration induced greater allodynia, much more stable threshold reduction was observed with the lower CFA concentration: on day 3 the thresholds decreased from 18.30 g to approximately 11 g (low) and 5 g (high), respectively, however a slight increase was observed in the case of higher CFA concentration (on days 5, 7, and 11). In all investigation days, topiramate showed significant anti-allodynic effect comparing the pre and post drug dose and comparing the vehicle treated to the drug treated groups. Sumatriptan also caused a significant threshold increase compared to pre dose thresholds (day 3) and also showed a slight anti-allodynic effect compared to the vehicle-treated group (day 3 and 5). In the present study CFA-induced chronic orofacial allodynia was reversed by topiramate in rats validating the model with the adjuvant analgesic. Other than establishing a validated orofacial pain-related syndrome model in rats, new ways are opened for the repurposing of topiramate.

[Trigeminal neuralgia: drug therapy : The new German guideline]

Trigeminal neuralgia is characterized by severe, lightning-like attacks of pain, which are mandatory for the diagnosis. The pain typically occurs on one side and is often triggered by simply touching the face, chewing or talking. In acute exacerbations, this can also hinder food and fluid intake, resulting in a life-threatening clinical picture. A distinction is made between classical, secondary and idiopathic trigeminal neuralgia. For the diagnosis of trigeminal neuralgia, the medical history and imaging procedures are key for classification. The only active substances approved for the treatment of trigeminal neuralgia in Germany are carbamazepine and phenytoin, which is why off-label drugs often need to be used if there is no or insufficient effect or inacceptable side effects. Cooperation between research and clinical practice to improve the care of affected patients is therefore essential.

Electroacupuncture and carbamazepine for patients with trigeminal neuralgia: a randomized, controlled, 2 × 2 factorial trial

BACKGROUND

Trigeminal neuralgia (TN) is difficult to treat due to its severe pain intensity and recurring episodes, which significantly impact quality of life.

OBJECTIVES

We aimed to assess the effectiveness of electroacupuncture (EA) in alleviating the pain intensity in TN, and to determine whether EA combined with low-dosage carbamazepine (CBZ) has a synergistic effect.

METHODS

A multi-centre, randomized, 2 × 2 factorial trial was conducted. Participants who met the inclusion criteria received active EA or sham EA for 60 min, three times a week for four weeks; CBZ (300 mg per day) or placebo for four weeks. The primary outcome was the change in visual analog scale (VAS) score from baseline to weeks 2, 4, 16, and 28. Secondary outcomes included quality of life and adverse events.

RESULTS

A total of 120 participants (75 females and 45 males; mean (SD) age, 58.5 (15.3) years) were included. The main effects of EA and CBZ were significant (P < 0.001), and there was a significant interaction was identified between the interventions (P = 0.041). Participants who received EA (mean difference [MD], -0.3 [95% CI, -0.40 to -0.20] at week 2; -1.6 [-1.70 to -1.50] at week 4; -1.1 [-1.31 to -0.89] at week 16; -0.8 [-1.01 to -0.59] at week 28), CBZ (MD, -0.6 [95% CI, -0.70 to -0.50] at week 2; -0.9 [-1.03 to -0.77] at week 4, -0.2 [-0.41 to 0.01] at week 16, 0.2 [-0.01 to 0.41] at week 28), and the combination of both (MD, -1.8 [95% CI, -1.90 to -1.70] at week 2; -3.7 [-3.83 to -3.57] at week 4, -3.4 [-3.61 to -3.19] at week 16, -2.9 [-3.11 to -2.69] at week 28) had a greater reduction in VAS score over the treatment phase than their respective control groups (sham EA, placebo, and sham EA plus placebo). EA-related adverse events (6/59, 10.17%) were lower than that of CBZ (15/59, 25.42%) during the whole phases.

CONCLUSIONS

EA or CBZ alone are effective treatments for TN, while the combination of EA and low-dosage CBZ exerts a greater benefit. These findings in this trial demonstrate that the combination of EA and low-dosage CBZ may be clinically effective under certain circumstances.

TRIAL REGISTRATION

NCT03580317.

Compared to oxcarbazepine and carbamazepine, botulinum toxin type A is a useful therapeutic option for trigeminal neuralgia symptoms: A systematic review

OBJECTIVES

This review aimed to compare the effectiveness of three treatments: BTX A, CBZ, and OXB, in managing trigeminal neuralgia (TN).

MATERIAL AND METHODS

We conducted a thorough search for research articles related to our issue using specific keywords on several databases, including Cochrane Central Register of Controlled Trials, Science Direct, Scopus, PubMed, Elsevier, Springer Journals, Ovid Medline, EBSCO, and Web of Science. Our focus was on publications from 1965 to 2023.

RESULTS

We retrieved 46 articles from the search and reviewed them carefully. Out of these, we selected 29 articles that met the inclusion criteria. Among the selected articles, 11 investigated the effects of CBZ and OXB, while 18 explored the impact of BTX A on the improvement of TN symptoms. The response rate ranged between 56% and 90.5% for CBZ and between 90.9% and 94% for OXB. The response rate for BTX A ranged between 51.4% and 100%. All these three treatments had a remarkable effect on the improvement of TN. Importantly, findings highlighted that side effects of CBZ and OXB could lead to treatment discontinuation in some cases, whereas BTX A's side effects have been minimal and less frequent.

CONCLUSIONS

Consequently, BTX A emerges as a promising alternative for TN treatment. However, additional clinical trials are necessary to validate this finding, and further research is required to establish a standardized protocol for administering BTX A in TN.

Safety and efficacy of carbamazepine in the treatment of trigeminal neuralgia: A metanalysis in biomedicine

Trigeminal neuralgia is a debilitating condition characterized by severe facial pain. Carbamazepine has been widely used as a first-line treatment option for trigeminal neuralgia, but there is a need to evaluate its safety and efficacy based on existing evidence. This meta-analysis aims to systematically assess the available literature and provide a comprehensive evaluation of the safety and efficacy of carbamazepine in the treatment of trigeminal neuralgia. A thorough search of electronic databases yielded a total of 15 relevant studies that met the inclusion criteria. The pooled analysis of these studies revealed that carbamazepine demonstrated significant efficacy in reducing pain intensity and frequency in patients with trigeminal neuralgia. Moreover, the drug was generally well-tolerated, with the most common adverse events being mild and transient. Subgroup analyses based on different dosages and treatment durations further supported the overall findings. However, caution should be exercised in patients with certain comorbidities or specific populations, as some rare but severe adverse events were reported. In conclusion, this meta-analysis provides strong evidence supporting the safety and efficacy of carbamazepine as a valuable therapeutic option for the management of trigeminal neuralgia. These results can guide clinicians in making informed decisions regarding the use of carbamazepine and contribute to optimizing treatment strategies for patients with trigeminal neuralgia. Further research is warranted to explore long-term safety and efficacy outcomes, as well as to compare carbamazepine with alternative treatment modalities.

Epigenetic HDAC5 Inhibitor Reverses Craniofacial Neuropathic Pain in Mice

Identifying and resolving molecular complexities underlying chronic neuropathic pain is a significant challenge. Among the numerous classes of histone deacetylases, Class I (HDAC 1-3) and Class III (sirtuins) have been best studied in experimental pain models where inhibitor pre-treatments but not post-treatments abrogate the development of pain-related behaviors. Post-treatment here in week 3 with less well-studied Class IIa HDAC4/5 selective inhibitor LMK235 diminishes the trigeminal ganglia increases of HDAC5 RNA and protein in two chronic orofacial neuropathic pain models to levels measured in naïve mice at week 10 post-model induction. HDAC4 RNA reported in lower limb inflammatory pain models is not evident in the trigeminal models. Many other gene alterations persisting at week 10 in the trigeminal ganglia (TG) are restored to naïve levels in mice treated with LMK235. Important pain-related upregulated genes Hoxc8,b9,d8; P2rx4, Cckbr, growth hormone (Gh), and schlafen (Slfn4) are greatly reduced in LMK235-treated mice. Fold increase in axon regeneration/repair genes Sostdc1, TTr, and Folr1 after injury are doubled by LMK235 treatment. LMK235 reduces the excitability of trigeminal ganglia neurons in culture isolated from nerve injured mice compared to vehicle-treated controls, with no effect on neurons from naïve mice. Electrophysiological characterization profile includes a shift where ∼20% of the small neurons recorded under LMK235-treated conditions are high threshold, whereas none of the neurons under control conditions have high thresholds. LMK235 reverses long-standing mechanical and cold hypersensitivity in chronic trigeminal neuropathic pain models in males and females (5,10 mg/kg), preventing development of anxiety- and depression-like behaviors. PERSPECTIVE: Data here support HDAC5 as key epigenetic factor in chronic trigeminal neuropathic pain persistence, validated with the study of RNA alterations, TG neuronal excitability, and pain-related behaviors. HDAC5 inhibitor given in week 3 restores RNA balance at 10 weeks, while upregulation remains for response to wound healing and chronic inflammation RNAs.

Atlas orthogonal chiropractic management of trigeminal neuralgia: A series of case reports

CONTEXT

Trigeminal neuralgia is a debilitating facial pain condition. Upper cervical chiropractic care has been mentioned as a possible solution OBJECTIVE: To determine the effects of Atlas Orthogonal upper cervical chiropractic technique adjustments on trigeminal neuralgia sufferers DESIGN: Case series SETTING: A private chiropractic practice PARTICIPANTS: Five persons with chronic, severe, daily trigeminal neuralgia pain, radiological findings of significant head tilt, pain upon upper cervical palpation, and supine leg length inequality INTERVENTIONS: Up to two consultations and/or Atlas Orthogonal adjustments a week for eight weeks OUTCOME MEASURES: Self-reported reduction in trigeminal neuralgia pain and changes in radiological findings, sensitivity to upper cervical palpation, and leg length inequality RESULTS: Four participants reported reduced trigeminal neuralgia pain, including two with complete cessation of pain. Three participants reduced medication dosages. One reported no change.

Neuropathic pain: From actual pharmacological treatments to new therapeutic horizons

Neuropathic pain, caused by a lesion or disease affecting the somatosensory system, affects between 3 and 17% of the general population. The treatment of neuropathic pain is challenging due to its heterogeneous etiologies, lack of objective diagnostic tools and resistance to classical analgesic drugs. First-line treatments recommended by the Special Interest Group on Neuropathic Pain (NeuPSIG) and European Federation of Neurological Societies (EFNS) include gabapentinoids, tricyclic antidepressants (TCAs) and selective serotonin noradrenaline reuptake inhibitors (SNRIs). Nevertheless these treatments have modest efficacy or dose limiting side effects. There is therefore a growing number of preclinical and clinical studies aim at developing new treatment strategies to treat neuropathic pain with better efficacy, selectivity, and less side effects. In this review, after a brief description of the mechanisms of action, efficacy, and limitations of current therapeutic drugs, we reviewed new preclinical and clinical targets currently under investigation, as well as promising non-pharmacological alternatives and their potential co-use with pharmacological treatments.

Considerations When Using Gabapentinoids to Treat Trigeminal Neuralgia: A Review

Despite the exemplary efficacy of voltage-gated sodium channel blockers as a first-line treatment of trigeminal neuralgia, the pharmacological management of this excruciating facial pain condition remains a major issue, as these first-line drugs produce intolerable side effects in a significant portion of patients. In addition, in patients with concomitant continuous pain, the efficacy of these drugs may drop, thus suggesting the opportunity to test the efficacy of different drug categories. The aim of this review is to provide current, evidence-based, knowledge about the use of gabapentin and other α2δ ligands in patients with trigeminal neuralgia. We searched for relevant papers within PubMed, EMBASE, the Cochrane Database of Systematic Reviews and the Clinical Trials database (ClinicalTrials.gov), considering publications up to April 2023. Two authors independently selected studies for inclusion and data extraction. The efficacy of α2δ ligands, gabapentin and pregabalin, has been assessed in seven controlled or open-label studies. Despite the low quality of evidence, the favorable tolerability profile and the possible action on concomitant continuous pain make this drug category of interest for future trials in trigeminal neuralgia.

Amelioration of nerve demyelination by hydrogen-producing silicon-based agent in neuropathic pain rats

Trigeminal neuralgia (TN) is a complex orofacial neuropathic pain. The crippling condition's underlying mechanism is still not completely understood. The main cause of lightning-like pain in patients with TN may be chronic inflammation that causes nerve demyelination. Nano-silicon (Si) can safely and continuously produce hydrogen in the alkaline environment of the intestine to exert systemic anti-inflammatory effects. Hydrogen has a promising anti-neuroinflammatory impact. The study aimed to determine how intra-intestinal application of a hydrogen-producing Si-based agent affected the demyelination of the trigeminal ganglion in TN rats. We discovered that increased expression of the NLRP3 inflammasome and inflammatory cell infiltration occurred concurrently with demyelination of the trigeminal ganglion in TN rats. We could determine that the neural effect of the hydrogen-producing Si-based agent was connected to the inhibition of microglial pyroptosis by using transmission electron microscopy. The results demonstrated that the Si-based agent reduced the infiltration of inflammatory cells and the degree of neural demyelination. In a subsequent study, it was discovered that hydrogen produced by a Si-based agent regulates the pyroptosis of microglia may through the NLRP3-caspase-1-GSDMD pathway, preventing the development of chronic neuroinflammation and consequently lowering the incidence of nerve demyelination. This study offers a novel strategy for elucidating the pathogenesis of TN and developing potential therapeutic drugs.

The efficacy and safety of gabapentin vs. carbamazepine in patients with primary trigeminal neuralgia: A systematic review and meta-analysis

Background

Drug therapy is the most commonly used treatment for primary trigeminal neuralgia (PTN), in which carbamazepine is the first-line drug. Recently, the anti-epileptic drug gabapentin has also been widely used in patients with PTN, but whether it can be used as a substitute for carbamazepine still needs to be verified. Our study aimed to assess the safety and efficacy of gabapentin vs. carbamazepine as a treatment for PTN.

Methods

We searched seven electronic databases for studies published as of 31 July 2022. All randomized controlled trials (RCTs) of gabapentin vs. carbamazepine on patients with PTN that met the inclusion criteria were included. Meta-analysis was conducted using Revman 5.4 and Stata 14.0, in which forest plots, funnel plots, and sensitivity analysis were performed. Mean difference (MD) and odds ratio (OR) with 95% confidence intervals (CIs) were used for the measurement indicators of continuous and categorical variables, respectively.

Results

A total of 18 RCTs with 1,604 patients were eventually identified. The meta-analysis showed that compared with the carbamazepine group, the gabapentin group significantly improved the effective rate (OR = 2.02, 95% CI 1.56 to 2.62, P < 0.001), reduced the adverse event rate (OR = 0.28, 95% CI 0.21 to 0.37, P < 0.001), and improved the visual analog scale (VAS) score (MD = -0.46, 95% CI -0.86 to -0.06, P = 0.03). Although the funnel plot showed evidence of publication bias, the sensitivity analysis revealed the stability of the results.

Conclusion

The current evidence showed that gabapentin may be superior to carbamazepine in relation to efficacy and safety in patients with PTN. It is crucial that more RCTs are conducted to confirm the conclusion in the future.

A Potential Role for Steroids in Acute Pain Management in Patients with Trigeminal Neuralgia

OBJECTIVE

Effective therapies for acute pain management in trigeminal neuralgia (TN) are limited. We aimed to investigate the role of steroids in TN patients experiencing acute pain flares.

METHODS

We retrospectively reviewed patients presenting to the emergency department of a tertiary care institution between 2014 and 2020 for acute TN pain flares. Patients were divided into those who received steroids versus those who did not. Presenting characteristics, admission and surgical intervention rates, Barrow Neurological Institute pain scores, pain recurrence rates, and surgical intervention within 6 months of discharge were obtained for each patient.

RESULTS

Our cohort comprised 151 patients, of whom 40 (26.5%) received steroids before admission and/or discharge. These patients were less likely to undergo surgical intervention to treat acute pain (P = 0.023). Specifically, patients receiving steroids were less likely to undergo combined glycerin and radiofrequency rhizotomy compared with patients not receiving steroids (P = 0.012). Frequency and dosage of opioid administration did not differ between groups. The steroids group demonstrated a lower average Barrow Neurological Institute pain score on discharge compared with the no steroids group (P = 0.013). Patients receiving steroids for acute pain management were less likely to undergo surgical intervention within 6 months of discharge than patients who did not receive steroids (P = 0.033).

CONCLUSIONS

Steroid administration in patients with acute TN pain flares may reduce the likelihood of surgical intervention both during admission and within 6 months of discharge. Future prospective studies should examine the efficacy of steroids as an adjunctive medication in acute TN pain management.

Xper-CT combined with laser-assisted navigation radiofrequency thermocoagulation in the treatment of trigeminal neuralgia

Objective

Our objective was to study the clinical feasibility of Xper-CT combined with laser-assisted radiofrequency thermocoagulation in the treatment of trigeminal neuralgia.

Materials and methods

A retrospective analysis was made of 60 patients with trigeminal neuralgia who visited the Affiliated Hospital of Binzhou Medical University from January 2019 to May 2021. According to the different surgical methods, we were divided into C-arm X-ray group and laser navigation group. The operation time, operative complications, post-operative 24 h, post-operative 3 and 6 months Barrow Neurotics Institute (BNI) score were recorded and compared.

Results

Compared with the C-arm X-ray-guided puncture group, Xper-CT combined with laser-assisted navigation has the obvious advantages of shorter total puncture time, shorter surgical time, higher success rate of first puncture, and better surgical effect.

Conclusion

Radiofrequency therapy of trigeminal neuralgia with Xper-CT combined with laser-assisted navigation has a good clinical effect and can be promoted and applied.

The Molecular Basis and Pathophysiology of Trigeminal Neuralgia

Trigeminal neuralgia (TN) is a complex orofacial pain syndrome characterized by the paroxysmal onset of pain attacks in the trigeminal distribution. The underlying mechanism for this debilitating condition is still not clearly understood. Decades of basic and clinical evidence support the demyelination hypothesis, where demyelination along the trigeminal afferent pathway is a major driver for TN pathogenesis and pathophysiology. Such pathological demyelination can be triggered by physical compression of the trigeminal ganglion or another primary demyelinating disease, such as multiple sclerosis. Further examination of TN patients and animal models has revealed significant molecular changes, channelopathies, and electrophysiological abnormalities in the affected trigeminal nerve. Interestingly, recent electrophysiological recordings and advanced functional neuroimaging data have shed new light on the global structural changes and the altered connectivity in the central pain-related circuits in TN patients. The current article aims to review the latest findings on the pathophysiology of TN and cross-examining them with the current surgical and pharmacologic management for TN patients. Understanding the underlying biology of TN could help scientists and clinicians to identify novel targets and improve treatments for this complex, debilitating disease.

Clinical Analysis of the Treatment of Primary Trigeminal Neuralgia by Percutaneous Balloon Compression

Purpose

To summarize the technical points and clinical effects of percutaneous balloon compression (PBC) in the treatment of primary trigeminal neuralgia.

Methods

The clinical data of 13 patients with trigeminal neuralgia who received PBC from April 2020 to July 2021 were retrospectively analyzed. VAS, VRS-4 and PPI were used to evaluate the postoperative pain relief. Different postoperative complications were analyzed.

Results

All patients had a smooth operation, the inflation volume of the balloon was 0.7 ml, the average compression time was 120 s, and there was no balloon rupture during the operation. On the day after operation, 12 patients (92.3%) had complete pain relief, and 1 patient (7.7%) was not satisfied with pain relief, but the pain disappeared 2 weeks after the operation. After operation, there were 12 patients with facial numbness in the affected side (92.3%), 3 patients with masseter muscle weakness (23.0%), 1 patient with herpes around the mouth (7.6%), and 1 patient with diplopia (7.6%).

Conclusion

PBC is an effective minimally invasive surgical method for the treatment of primary trigeminal neuralgia. It is suitable for the elderly and infirm people, those who cannot tolerate general anesthesia or are afraid of surgery, and patients who had undergone surgery but relapsed after surgery. However, it is necessary to pay attention to the serious facial numbness and postoperative masticatory weakness. These discomforts are generally relieved after half a year.