Etiologies of iatrogenic occipital nerve injury: And outcomes following treatment with nerve decompression surgery.

INTRODUCTION: This study analyzed the etiologies and treatment of iatrogenic occipital nerve injuries. METHODS: Patients with occipital neuralgia (ON) who were screened for occipital nerve decompression surgery were prospectively enrolled. Patients with iatrogenic occipital nerve injuries who underwent nerve decompression surgery were identified. Data included surgical history, pain characteristics, and surgical technique. Outcomes included pain frequency (days/month), duration (h/day), intensity (0-10), migraine headache index (MHI), and patient-reported percent-resolution of pain. RESULTS: Among the 416 patients with ON, who were screened for occipital nerve decompression surgery, 12 (2.9%) cases of iatrogenic occipital nerve injury were identified and underwent surgical treatment. Preoperative headache frequency was 30 (±0.0) days/month, duration was 19.4 (±6.9) h, and intensity was 9.2 (±0.9). Neuroma excision was performed in 5 cases followed by targeted muscle reinnervation in 3, nerve cap in 1, and muscle burial in 1. In patients without neuromas, greater occipital nerve decompression and/or lesser occipital nerve neurectomy were performed. At the median follow-up of 12 months (IQR 12-12 months), mean pain frequency was 4.0 (±6.6) pain days/month (p < 0.0001), duration was 6.3 (±8.9) h (p < 0.01), and intensity was 4.4 (±2.8) (p < 0.001). Median patient-reported resolution of pain was 85% (56.3%-97.5%) and success rate was (≥50% MHI improvement) 91.7%. CONCLUSIONS: Iatrogenic occipital nerve injuries can be caused by various surgical interventions, including craniotomies, cervical spine interventions, and scalp tumor resections. The associated pain can be severe and chronic. Iatrogenic ON should be considered in the differential diagnosis of post-operative headaches and can be treated with nerve decompression surgery or neuroma excision with reconstruction of the free nerve end.

Insights into the pathophysiology and response of persistent spinal pain syndrome type 2 to spinal cord stimulation: a human genome-wide association study.

BACKGROUND: Spinal cord stimulation (SCS) provides pain relief for some patients with persistent spinal pain syndrome type 2 (PSPS 2), but the precise mechanisms of action and prognostic factors for a favorable pain response remain obscure. This in vivo human genome-wide association study provides some pathophysiological clues. METHODS: We performed a high-density oligonucleotide microarray analysis of serum obtained from both PSPS 2 cases and pain-free controls who had undergone lower back spinal surgery at the study site. Using multivariate discriminant analysis, we tried to identify different expressions between mRNA transcripts from PSPS 2 patients relative to controls, SCS responders to non-responders, or SCS responders to themselves before starting SCS. Gene ontology enrichment analysis was used to identify the biological processes that best discriminate between the groups of clinical interest. RESULTS: Thirty PSPS 2 patients, of whom 23 responded to SCS, were evaluated together with 15 pain-free controls. We identified 11 significantly downregulated genes in serum of PSPS 2 patients compared with pain-free controls and two significantly downregulated genes once the SCS response became apparent. All were suggestive of enhanced inflammation, tissue repair mechanisms and proliferative responses among the former. We could not identify any gene differentiating patients who responded to SCS from those who did not respond. CONCLUSIONS: This study points out various biological processes that may underlie PSPS 2 pain and SCS therapeutic effects, including the modulation of neuroimmune response, inflammation and restorative processes.

Conservative Management of Occipital Neuralgia Supported by Physical Therapy: A Review of Available Research and Mechanistic Rationale to Guide Treatment.

PURPOSE OF REVIEW: Conservative management is consistently recommended as a first line intervention for occipital neuralgia (ON); however, there is limited clinical research regarding conservative intervention for ON. This lack of research may lead to underutilization or unwarranted variability in conservative treatment. This article provides mechanism-based guidance for conservative management of ON as a component of a multimodal treatment approach, and discusses the role of the physical therapist in the care team. It also highlights opportunities for further research to refine conservative management of this condition. RECENT FINDINGS: Published research on conservative interventions specific to ON is limited to very low-quality evidence for the use of TENS. The contemporary shift toward precision pain management emphasizing treatment based on a patient's constellation of clinical features-a phenotype-rather than solely a diagnosis provides more personalized and specifically targeted pain treatment. This paradigm can guide treatment in cases where diagnosis-specific research is lacking and can be used to inform conservative treatment in this case. Various conservative interventions have demonstrated efficacy in treating many of the symptoms and accepted etiologies of ON. Conservative interventions provided by a physical therapist including exercise, manual therapy, posture and biomechanical training, TENS, patient education, and desensitization have mechanistic justification to treat symptoms and causes of ON. Physical therapists have adequate time and skill to provide such progressive and iterative interventions and should be included in a multimodal treatment plan for ON. Further research is required to determine appropriate dosing, sequencing, and progression of conservative treatments.

A Comparison Between the Efficacy of Trigeminal Ganglion Radiofrequency Thermocoagulation and Ultrasound-Guided Maxillary-Mandibular Nerve Pulsed Radiofrequency in the Treatment of Trigeminal Neuralgia: A Randomized Clinical Trial.

Background and objective Trigeminal neuralgia (TN) is a debilitating disorder characterized by acute episodic attacks of pain that significantly impair patients' quality of life and overall functioning. Initial therapeutic strategies to treat this condition include pharmacological options, particularly carbamazepine. In cases with resistance to dose escalation and polypharmacy, interventional procedures may be warranted. The primary aim of this study was to compare the efficacy of trigeminal ganglion (TG) radiofrequency thermocoagulation (RFT) and ultrasound (US)-guided maxillary/mandibular (max/mand) nerve pulsed radiofrequency (PRF) for treating TN, based on the findings at six months post-treatment. The secondary aims were to assess the impact of these interventions on drug consumption and interventional safety based on adverse events. Methods This prospective, randomized, single-blind study was conducted at a single pain clinic. Forty-four patients were randomized into two groups. Group RFT received TG RFT at 60 °C, 65 °C, and 70 °C for 60 seconds each, whereas Group PRF received max/mand PRF for 240 seconds. Pain relief was assessed by using the numeric rating scale (NRS) and intervention effectiveness on medication consumption was evaluated by using the Medication Quantification Scale III (MQS III). The rates of intervention-related adverse events were also compared. Results Both RFT and PRF significantly alleviated pain at one and six months post-treatment compared to baseline (p<0.05). No statistical differences were found in the NRS and MQS III scores between the groups. At six months, 77.3% of RFT patients and 63.9% of PRF patients experienced at least 50% pain relief, with no statistically significant difference. Hypoesthesia occurred in two RFT patients, and masseter weakness was observed in one patient, while no adverse events were reported in the PRF group. Conclusions TG RFT and max/mand PRF are effective treatments for TN. US-guided max/mand PRF, which avoids RFT-associated complications and radiation exposure, may be the superior and preferable option. In this study, the potential space between the coronoid process and maxilla was used to access the maxillary nerve during the maxillary block and PRF procedures, in contrast to the classical approach through the mandibular notch. Further large-scale randomized controlled trials are required to gain deeper insights into the topic.

Novel insights into STIM1's role in store-operated calcium entry and its implications for T-cell mediated inflammation in trigeminal neuralgia.

This investigation aims to elucidate the novel role of Stromal Interaction Molecule 1 (STIM1) in modulating store-operated calcium entry (SOCE) and its subsequent impact on inflammatory cytokine release in T lymphocytes, thereby advancing our understanding of trigeminal neuralgia (TN) pathogenesis. Employing the Gene Expression Omnibus (GEO) database, we extracted microarray data pertinent to TN to identify differentially expressed genes (DEGs). A subsequent comparison with SOCE-related genes from the Genecards database helped pinpoint potential target genes. The STRING database facilitated protein-protein interaction (PPI) analysis to spotlight STIM1 as a gene of interest in TN. Through histological staining, transmission electron microscopy (TEM), and behavioral assessments, we probed STIM1's pathological effects on TN in rat models. Additionally, we examined STIM1's influence on the SOCE pathway in trigeminal ganglion cells using techniques like calcium content measurement, patch clamp electrophysiology, and STIM1- ORAI1 co-localization studies. Changes in the expression of inflammatory markers (TNF-α, IL-1ß, IL-6) in T cells were quantified using Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) in vitro, while immunohistochemistry and flow cytometry were applied in vivo to assess these cytokines and T cell count alterations. Our bioinformatic approach highlighted STIM1's significant overexpression in TN patients, underscoring its pivotal role in TN's etiology and progression. Experimental findings from both in vitro and in vivo studies corroborated STIM1's regulatory influence on the SOCE pathway. Furthermore, STIM1 was shown to mediate SOCE-induced inflammatory cytokine release in T lymphocytes, a critical factor in TN development. Supportive evidence from histological, ultrastructural, and behavioral analyses reinforced the link between STIM1-mediated SOCE and T lymphocyte-driven inflammation in TN pathogenesis. This study presents novel evidence that STIM1 is a key regulator of SOCE and inflammatory cytokine release in T lymphocytes, contributing significantly to the pathogenesis of trigeminal neuralgia. Our findings not only deepen the understanding of TN's molecular underpinnings but also potentially open new avenues for targeted therapeutic strategies.

Preoperative visualization of the greater occipital nerve with magnetic resonance imaging in candidates for occipital nerve decompression for headaches.

Occipital nerve decompression is effective in reducing headache symptoms in select patients with migraine and occipital neuralgia. Eligibility for surgery relies on subjective symptoms and responses to nerve blocks and Onabotulinum toxin A (Botox) injections. No validated objective method exists for detecting occipital headache pathologies. The purpose of the study is to explore the potential of high-resolution Magnetic Resolution Imaging (MRI) in identifying greater occipital nerve (GON) pathologies in chronic headache patients. The MRI protocol included three sequences targeting fat-suppressed fluid-sensitive T2-weighted signals. Visualization of the GON involved generating 2-D image slices with sequential rotation to track the nerve course. Twelve patients underwent pre-surgical MRI assessment. MRI identified four main pathologies that were validated against intra-operative examination: GON entanglement by the occipital artery, increased nerve thickness and hyperintensity suggesting inflammation compared to the non-symptomatic contralateral side, early GON branching with rejoining at a distal point, and a connection between the GON and the lesser occipital nerve. MRI possesses the ability to visualize the GON and identify suspected trigger points associated with headache symptoms. This case series highlights MRI's potential to provide objective evidence of nerve pathology. Further research is warranted to establish MRI as a gold standard for diagnosing extracranial contributors in headaches.

Cost-Effectiveness of the Recombinant Zoster Vaccine Among People Living With HIV in Japan.

OBJECTIVES: People living with HIV (PLWHIV) are susceptible to opportunistic infections including herpes zoster (HZ) and postherpetic neuralgia (PHN). The recombinant zoster vaccine (RZV) (Shingrix) is available in some countries. However, the cost-effectiveness for PLWHIV remains unknown. This study aimed to analyze the cost-effectiveness of RZV for PLWHIV ≥50 years old. METHODS: A Markov model was developed to compare the cost-effectiveness of the 2-dose RZV immunization program with no RZV immunization for PLWHIV aged ≥50 years. We built the model with a yearly cycle over a 30-year period and 6 health conditions: HZ free, HZ, PHN, HZ/PHN recovery, HZ recurrence, and death. The parameters in the model were based on previous studies and a nationwide administrative claims database in Japan. The incremental cost-effectiveness ratio (ICER), expressed as Japanese yen (JPY) per the quality-adjusted life-years (QALYs), was estimated from a societal perspective. We conducted a one-way deterministic sensitivity analysis, probabilistic sensitivity analysis with Monte Carlo simulations of 10 000 samples, and scenario analyses. RESULTS: The ICER of the 2-dose RZV immunization program over no RZV immunization was 78 777 774 JPY (approximately 600 000 US dollars)/QALY. The one-way deterministic sensitivity analysis showed that HZ-related utility was the most significant for ICER. All estimates in the probabilistic sensitivity analysis were located above the willingness-to-pay threshold of 5 million JPY/QALY. CONCLUSIONS: Our study revealed that no RZV immunization was more cost-effective than the 2-dose RZV immunization program for PLWHIV aged ≥50 years. This may be useful in evidence-based policy making.

Genitofemoral Nerve Variation: An Attempt to Explain the Embryological Basis via a Case Report.

The genitofemoral nerve (GFN) presents with a variable course in nearly half of the population. This variation can be seen in its availability, course, and branching. Here, a notable case during a cadaveric dissection revealed an unusually high bifurcation of the GFN on the left side, contrasting with the typical bifurcation observed on the right. This divergence was highlighted using colored markers to aid educational visualization, facilitating a comprehensive learning experience about the nerve's variability and its functional implications, such as the cremasteric reflex. Embryologically, these variations stem from the migratory paths of myotomes during development, influenced by extrinsic signals and growth factors. Despite the high incidence of anatomical variability, the muscular structure remains consistent, suggesting that the nerve's formation is more susceptible to developmental shifts than the muscles it innervates. Clinically, understanding GFN variations is crucial due to the nerve's involvement in conditions like genitofemoral neuropathy, which can arise from surgical procedures. Accurate knowledge of these variations aids in precise diagnostic and therapeutic interventions, reducing complications, and enhancing patient outcomes in lower abdominal and groin surgeries. However, further research is needed to elucidate the exact embryological and genetic underpinnings of these variations.

Partial sensory rhizotomy in recurrent trigeminal neuralgia. our experience and literature review.

BACKGROUND AND OBJECTIVE: Trigeminal Neuralgia (NT) is a common pathology in Neurosurgery. It can be classified as idiopathic or secondary to other pathologies, such as Multiple Sclerosis (MS). Several surgical treatments have been described, some of them being replaced by more modern techniques. Partial sensory rhizotomy (PSR), described by Dandy is a technique replaced by other techniques due to its permanent side effects. We present our experience with this technique in patients with recurrent NT. METHODS AND MATERIALS: A retrospective review is carried out on six patients who underwent surgery at our center from 2018 to 2023 using the PSR technique. RESULTS: All the patients intervened showed significant clinical improvement, except one patient who required reintervention due to uncontrolled pain. According to the Barrow Neurological Institute (BNI) scale, 80% (4/5) of patients showed improvement from grade V to grades I/II except for one of them. This patient suffered from MS. Additionally, one patient presented a corneal ulcer after surgery due to impairment of the corneal reflex. CONCLUSION: In our experience, PSR is a valid treatment option in selected patients with recurrent TN. It has a low incidence of complications with an adequate surgical technique and anatomical knowledge of the region. To the best of our knowledge, we are one of the few centers in Spain to publish our results with PSR in the last ten years. In our study, we report good results in pain control withdrawing medication in 67% (4/6) of the operated patients.

Robot assisted exploration of the Alcock canal: a novel surgical technique.

OBJECTIVE: To demonstrate a safe and reproducible surgical approach to the Alcock canal with a full decompression of the pudendal nerve. SETTING: Pudendal neuralgia, a condition causing debilitating pelvic pain, is traditionally managed through a trans-gluteal incision.1-2 This surgical approach offers limited visualization and ability for nerve decompression.3 With the current technique, a full exposure and decompression of the pudendal nerve was achieved. PARTICIPANTS: A 44-year-old para 2 with symptoms of left pudendal neuralgia. INTERVENTIONS: A 44-year-old para 2 presented with burning vaginal pain radiating to the left groin that was aggravated with sitting. She underwent a robotic-assisted left sacrospinous ligament transection and fasciotomy of the obturator internus muscle for suspected pudendal neuralgia. The surgery was performed with three robotic ports using the daVinci® Xi robotic system. CONCLUSION: With the enhanced access to the pudendal nerve provided by the novel surgical technique demonstrated in this study, a more comprehensive nerve decompression can be performed. This technique was successfully applied to a patient with pudendal neuralgia. There were no immediate intra-operative or post-operative complications. In short-term follow-up, the patient had significant relief of preoperative symptoms. While all surgical procedures for pudendal neuralgia have a risk of pudendal nerve and vessel injury,4 the presented technique has the potential to limit these risks by providing an enhanced view of the relevant anatomy. Future adaptation and refinement of this technique may contribute to the advancement of the surgical management of pudendal neuralgia.

Microvascular Decompression versus Radiofrequency Ablation in Trigeminal Neuralgia of the Maxillary and Mandibular Divisions.

Background Although medical treatment is the mainstay of therapy, in trigeminal neuralgia (TN), patients failing to respond to it make them candidates to ablative or nonablative procedures. Objective The aim of this study was to compare the outcome of Microvascular decompression (MVD) and radiofrequency (RF) thermocoagulation in the management of TN affecting the mandibular and maxillary divisions. Materials and Methods Retrospective analysis of the data of 40 patients suffering from intractable classical TN affecting the maxillary or mandibular divisions or both was carried out. Twenty patients were operated upon by MVD of the trigeminal nerve; and 20 had RF ablation of the maxillary or mandibular divisions of the trigeminal nerve or both. Results In MVD the overall successful outcome was achieved in 16 patients (80%), while the failure was in 4 patients (20%) of which 3 had a fair outcome and 1 patient had a poor outcome. Whereas in RF the overall successful outcome was achieved in 17 patients (85%), while the failure was in 3 patients (15%) of which 2 had a fair outcome and 1 patient had a poor outcome. Outcome was insignificantly different between both groups ( p -value 0.806). Conclusion MVD and RF ablation represent safe and efficacious surgical choices for addressing TN that encompasses both the mandibular and maxillary divisions. Long-term follow-up studies demonstrate that MVD consistently yields favorable outcomes, establishing it as the preferred primary surgical technique, unless contraindicated by the patient's general health and specific needs.

Awake neurosurgery: Advancements in microvascular decompression for trigeminal neuralgia.

Background: The treatment landscape for trigeminal neuralgia (TN) involves various surgical interventions, among which microvascular decompression (MVD) stands out as highly effective. While MVD offers significant benefits, its success relies on precise surgical techniques and patient selection. In addition, the emergence of awake surgery techniques presents new opportunities to improve outcomes and minimize complications associated with MVD for TN. Methods: A thorough review of the literature was conducted to explore the effectiveness and challenges of MVD for TN, as well as the impact of awake surgery on its outcomes. PubMed and Medline databases were searched from inception to March 2024 using specific keywords "Awake Neurosurgery," "Microvascular Decompression," AND "Trigeminal Neuralgia." Studies reporting original research on human subjects or preclinical investigations were included in the study. Results: This review highlighted that MVD emerges as a highly effective treatment for TN, offering long-term pain relief with relatively low rates of recurrence and complications. Awake surgery techniques, including awake craniotomy, have revolutionized the approach to MVD, providing benefits such as reduced postoperative monitoring, shorter hospital stays, and improved neurological outcomes. Furthermore, awake MVD procedures offer opportunities for precise mapping and preservation of critical brain functions, enhancing surgical precision and patient outcomes. Conclusion: The integration of awake surgery techniques, particularly awake MVD, represents a significant advancement in the treatment of TN. Future research should focus on refining awake surgery techniques and exploring new approaches to optimize outcomes in MVD for TN.

Genetics of causal relationships between circulating inflammatory proteins and postherpetic neuralgia: a bidirectional Mendelian randomization study.

Objective: According to data from several observational studies, there is a strong association between circulating inflammatory cytokines and postherpetic neuralgia (PHN), but it is not clear whether this association is causal or confounding; therefore, the main aim of the present study was to analyze whether circulating inflammatory proteins have a bidirectional relationship with PHN at the genetic inheritance level using a Mendelian randomization (MR) study. Methods: The Genome-Wide Association Study (GWAS) database was used for our analysis. We gathered data on inflammation-related genetic variation from three GWASs of human cytokines. These proteins included 91 circulating inflammatory proteins, tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein 1b (MIP-1b), and CXC chemokine 13 (CXCL13). The PHN dataset was obtained from the FinnGen biobank analysis round 5, and consisted of 1,413 cases and 275,212 controls. We conducted a two-sample bidirectional MR study using the TwoSampleMR and MRPRESSO R packages (version R.4.3.1). Our main analytical method was inverse variance weighting (IVW), and we performed sensitivity analyses to assess heterogeneity and pleiotropy, as well as the potential influence of individual SNPs, to validate our findings. Results: According to our forward analysis, five circulating inflammatory proteins were causally associated with the development of PHN: interleukin (IL)-18 was positively associated with PHN, and IL-13, fibroblast growth factor 19 (FGF-19), MIP-1b, and stem cell growth factor (SCF) showed reverse causality with PHN. Conversely, we found that PHN was closely associated with 12 inflammatory cytokines, but no significant correlation was found among the other inflammatory factors. Among them, only IL-18 had a bidirectional causal relationship with PHN. Conclusion: Our research advances the current understanding of the role of certain inflammatory biomarker pathways in the development of PHN. Additional verification is required to evaluate the viability of these proteins as targeted inflammatory factors for PHN-based treatments.

Neurexin 3 Regulates Synaptic Connections Between Central Amygdala Neurons and Excitable Cells of the Lateral Parabrachial Nucleus in Rats with Varicella Zoster Induced Orofacial Pain.

Introduction: Herpes Zoster in humans is the result of varicella zoster virus (VZV) infection. Injecting rats with varicella zoster virus produces pain similar to herpes zoster "shingles" pain in humans. . In a previous study, orofacial pain was induced by injecting the whisker pad of male rats with VZV and the pain response increased after attenuating neurexin 3 (Nrxn3) expression in the central amygdala. Neurons descend from the central amygdala to the lateral parabrachial nucleus and orofacial pain signals ascend to the lateral parabrachial nucleus. GABAergic neurons within the central amygdala regulate pain by inhibiting activity within the lateral parabrachial nucleus. Attenuating Nrxn3 expression in the central amygdala increased GABA release in the lateral parabrachial nucleus suggesting Nrxn3 controls pain by regulating GABA release. Nrxn3 can also control synaptic connections between neurons, and we hypothesized that Nrxn3 knockdown in the central amygdala would reduce the number of GABAergic synaptic connections in the lateral parabrachial nucleus and increase VZV associated pain. Methods: To test this idea, the number of synaptic connections between GABAergic cells of the central amygdala and excitatory or dynorphin positive neurons within the lateral parabrachial nucleus were quantitated after infusion of a virus expressing synaptophysin. Synaptophysin is a synaptic vesicle protein that labels neuronal synaptic connections. These connections were measured in rats with and without whisker pad injection of VZV and knockdown of Nrxn3 within the central amygdala. Orofacial pain was measured using a place escape avoidance paradigm. Results: GABAergic synaptic connections were reduced in the lateral parabrachial nucleus after Nrxn3 knockdown. Rats with a reduction in the number of connections had an increase in VZV associated orofacial pain. Immunostaining with the pain marker prodynorphin indicated that the reduction in GABAergic connections was primarily associated with prodynorphin positive neurons. Discussion: The results suggest Nrxn3 reduces VZV associated orofacial pain, in part, by enhancing synaptic connections between GABA cells of the central amygdala and pain neurons within the lateral parabrachial nucleus.

A Prognostic Model Incorporating Relevant Peripheral Blood Inflammation Indicator to Predict Postherpetic Neuralgia in Patients with Acute Herpes Zoster.

Objective: To determine the risk of postherpetic neuralgia (PHN) in patients with acute herpes zoster (HZ), this study developed and validated a novel clinical prediction model by incorporating a relevant peripheral blood inflammation indicator. Methods: Between January 2019 and June 2023, 209 patients with acute HZ were categorized into the PHN group (n = 62) and the non-PHN group (n = 147). Univariate and multivariate logistic regression analyses were conducted to identify risk factors serving as independent predictors of PHN development. Subsequently, a nomogram prediction model was established, and the discriminative ability and calibration were evaluated using the receiver operating characteristic curve, calibration plots, and decision curve analysis (DCA). The nomogram model was internally verified through the bootstrap test method. Results: According to univariate logistic regression analyses, five variables, namely age, hypertension, acute phase Numeric Rating Scale (NRS-11) score, platelet-to-lymphocyte ratio (PLR), and systemic immune inflammation index, were significantly associated with PHN development. Multifactorial analysis further unveiled that age (odds ratio (OR) [95% confidence interval (CI)]: 2.309 [1.163-4.660]), acute phase NRS-11 score (OR [95% CI]: 2.837 [1.294-6.275]), and PLR (OR [95% CI]: 1.015 [1.010-1.022]) were independent risk factors for PHN. These three predictors were integrated to establish the prediction model and construct the nomogram. The area under the receiver operating characteristic curve (AUC) for predicting the PHN risk was 0.787, and the AUC of internal validation determined using the bootstrap method was 0.776. The DCA and calibration curve also indicated that the predictive performance of the nomogram model was commendable. Conclusion: In this study, a risk prediction model was developed and validated to accurately forecast the probability of PHN after HZ, thereby demonstrating favorable discrimination, calibration, and clinical applicability.

Neurological phenotypes and treatment outcomes in Eagle syndrome: systematic review and meta-analysis.

Background: Eagle syndrome is caused by an elongated styloid process affecting carotid arteries and cranial nerves. Pain, dysphagia, tinnitus, paresthesia (classic subtype), and neurovascular events (vascular subtype) may be triggered by head movements or arise spontaneously. However, Eagle syndrome remains underappreciated in the neurological community. We aimed to determine the most common neurological and non-neurological clinical presentations in patients with Eagle syndrome and to assess the clinical outcome post-surgical resection in comparison to non-surgical therapies. Methodology: We conducted a systematic review of patient-level data on adults with Eagle syndrome, following PRISMA guidelines. We extracted data on demographics, presenting symptoms, neurological deficits, radiological findings, and treatments, including outcomes and complications, from studies in multiple indexing databases published between 2000 and 2023. The study protocol is registered with PROSPERO. Results: In total, 285 studies met inclusion criteria, including 497 patients with Eagle syndrome (mean age 47.3 years; 49.8% female). Classical Eagle (370 patients, 74.5%) was more frequent than vascular Eagle syndrome (117 patients, 23.5%, p < 0.0001). Six patients (1.2%) presented with both variants and the subvariant for four patients (0.8%) was unknown. There was a male preponderance (70.1% male) in the vascular subtype. A history of tonsillectomy was more frequent in classic (48/153 cases) than in vascular (2/33 cases) Eagle syndrome (Odds Ratio 5.2, 95% CI [1.2-22.4]; p = 0.028). By contrast, cervical movements as trigger factors were more prevalent in vascular (12/33 cases) than in classic (7/153 cases) Eagle syndrome (Odds Ratio 7.95, 95% CI [2.9-21.7]; p = 0.0001). Headache and Horner syndrome were more frequent in vascular Eagle syndrome and dysphagia and neck pain more prominent in classic Eagle syndrome (all p < 0.01). Surgically treated patients achieved overall better outcomes than medically treated ones: Eighty-one (65.9%) of 123 medically treated patients experienced improvement or complete resolution, while the same applied to 313 (97.8%) of 320 surgical patients (Odds Ratio 1.49, 95% CI [1.1-2.0]; p = 0.016). Conclusions: Eagle syndrome is underdiagnosed with potentially serious neurovascular complications, including ischemic stroke. Surgical treatment achieves better outcomes than conservative management. Although traditionally the domain of otorhinolaryngologist, neurologist should include this syndrome in differential diagnostic considerations because of the varied neurological presentations that are amenable to effective treatment.

Multiple sclerosis relapse presenting as trigeminal neuralgia.

I present here a case of trigeminal neuralgia (TGN), which is a highly disabling disorder characterized by brief and recurrent shock-like episodes of facial pain. TGN occurs in 2% of people with MS. A 54-year-old woman diagnosed with multiple sclerosis (MS) in 2008 and who was in remission stopped taking her disease-modifying therapy (DMT) in 2018 due to a lack of relapses presented to our facility with excruciating right facial pain. Magnetic resonance imaging (MRI) of the brain with gadolinium showed enhancing plaque involving the proximal cisternal portion of the right trigeminal nerve on axial and sagittal sections. She was started on carbamazepine 300 mg 4 times a day. This case highlights the need for early diagnosis by MRI with gadolinium enhancement and prompt initiation of treatment helped her pain to subside and was able to return a week later to the MS clinic to be restarted on her prior DMT to prevent further MS relapses.

The efficacy of repetitive transcranial magnetic stimulation in postherpetic neuralgia: a meta-analysis of randomized controlled trials.

Purpose: This systematic review and meta-analysis aimed to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) in postherpetic neuralgia (PHN). Methods: Through an extensive search in four databases until October 2023, we selected five randomized controlled trials adhering to our specific criteria, involving 257 patients in total. For continuous outcomes, the standardized mean difference (SMD) was calculated. Heterogeneity among the studies was assessed using Cochran's I 2 and Q statistics, adopting a random-effects model for I 2 values over 50%. For assessing potential publication bias, we utilized both funnel plot and Egger's test. Results: Our analysis found that rTMS reduced the overall visual analogue scale (VAS) (SMD: -1.52, 95% CI: -2.81 to -0.23, p = 0.02), VAS at 1 month post-treatment (SMD: -2.21, 95% CI: -4.31 to -0.10, p = 0.04), VAS at 3 months post-treatment (SMD: -1.51, 95% CI: -2.81 to -0.22, p = 0.02), as well as patients' global impression of change scale (PGIC) (SMD: -1.48, 95% CI: -2.87 to -0.09, p = 0.04) and short-form McGill pain questionnaire (SF-MPQ) (SMD: -1.25, 95% CI: -2.41 to -0.09, p = 0.03) compared to the sham-rTMS group. Conclusion: Our study suggests that rTMS might have a potential alleviating effect on PHN symptoms. However, due to the limited number of studies and variations in rTMS parameters, larger sample studies involving more diverse populations, as well as further clarification of the most appropriate stimulation protocol, are still needed. Systematic review registration: https://www.crd.york.ac.uk/prospero/, Identifier ID: CRD42023488420.

Ultrasound guided platelet rich plasma injections for post-traumatic greater occipital neuralgia following concussion: a pilot randomized controlled trial.

Background: Treatment for post-traumatic greater occipital neuralgia (GON) includes serial injections of steroid/anesthetic. While these injections can alleviate pain, effects can be transient, frequently lasting only 1 month. As a potential alternative, platelet-rich plasma (PRP) injections are an emerging biological treatment with beneficial effects in peripheral nerve disorders. We investigated the feasibility, safety, and effectiveness of a single PRP injection for post-traumatic GON in comparison to saline or steroid/anesthetic injection. Methods: In this pilot randomized, double-blinded, placebo-controlled trial, 32 adults with post-traumatic GON were allocated 1:1:1 to receive a single ultrasound-guided injection of (1) autologous PRP (2) steroid/anesthetic or (3) normal saline. Our primary outcome was feasibility (recruitment, attendance, retention) and safety (adverse events). Exploratory measures included headache intensity and frequency (daily headache diaries) and additional questionnaires (headache impact, and quality of life) assessed at pre-injection, 1 week, 1 month, and 3 months post-injection. Results: We screened 67 individuals, 55% were eligible and 95% of those participated. Over 80% of daily headache diaries were completed with 91% of participants completing the 3-month outcome questionnaires. No serious adverse events were reported. There were no significant differences between groups for headache intensity or frequency. Headache impact on function test-6 scores improved at 3 month in the PRP (ß = -9.7, 95% CI [-15.6, -3.74], p = 0.002) and saline (ß = -6.7 [-12.7, -0.57], p = 0.033) groups but not steroid/anesthetic group (p = 0.135). Conclusion: PRP is a feasible and safe method for treating post-traumatic GON with comparable results to saline and steroid/anaesthetic. Further trials with larger sample sizes are required.Clinical trial registration:https://clinicaltrials.gov/, identifier NCT04051203.

Health Disparities in the Neurosurgical Care of Patients with Trigeminal Neuralgia.

BACKGROUND: There has been limited investigation into how social determinants of health impact treatment outcomes in patients with trigeminal neuralgia (TN). We aimed to investigate how social determinants of health may alter the course of clinical care for patients with TN. METHODS: The electronic medical record was queried for patients with a diagnosis of TN comanaged by neurosurgeons and other facial pain specialists at our medical center. Area Deprivation Index served as a proxy for socioeconomic status (SES). Multivariable linear regression models were performed using RStudio to assess the impact of social determinants on the time to neurosurgical referral and surgical intervention. RESULTS: A total of 229 patients (mean age 50 years, 74% female) were included. Of these, 135 (60%) patients underwent a neurosurgical procedure after referral, the most common being microvascular decompression (n = 84, 62%) (Table 1). Most of the patients were white (76.3%) and insured by Medicare (51.8%), followed by private insurance (38.6%). Age and sex were significant predictors of time to neurosurgical referral after symptom onset, as older patients (P < 0.01, Figure 3) and females (P = 0.02) tended to have a greater delay between symptom onset and specialist referral. Race, SES, and insurance status were not significantly associated with time-to-referral or time-to-treatment. CONCLUSION: This study found that older and female patients with TN had a longer time from symptom onset to specialist referral. Based on these data, there is no association between race, SES, and insurance status with time-to-referral or time-to-treatment in patients with TN.