Trigeminal Research Articles

Comparative safety and efficacy of percutaneous radiofrequency thermocoagulation and percutaneous balloon compression in CT-guided and local anesthesia for recurrent trigeminal neuralgia.

There are several ways to treat trigeminal neuralgia (TN); however, TN may recur after treatment. Although microvascular decompression (MVD) is considered an effective treatment for trigeminal neuralgia, patients with recurrence may not be willing to undergo craniotomy. This study compared the safety and efficacy of percutaneous radiofrequency thermocoagulation and percutaneous balloon compression for treating recurrent trigeminal neuralgia. This was a prospective non-randomized controlled study. A total of 52 with recurrent TN were scheduled to undergo surgery in our Hospital from January-June 2021. The patients were classified into percutaneous radiofrequency thermocoagulation (PRT) and percutaneous balloon compression (PBC) groups based on the treatment. All surgeries were performed under computed tomography guidance and local anesthesia. Post-operative complications were also observed. Pain was assessed using the visual analog scale (VAS) and Barrow Neurological Institute (BNI) scale. Efficacy indices were evaluated at 3, 6, 12, and 18 months after surgery. During follow-up, the efficacy rates of the two methods within 18 months were 76.0 and 88.9%, respectively. All patients had hypoesthesia on the affected side, and no severe complications. Notably, 5 patients (20%) in the PRT group with multiple-branch pain, including the first branch of the trigeminal nerve (V1) pain in the PRT group, received radiofrequency therapy for the supraorbital notch (foramen) after puncture of the foramen ovale. However, multiple pain episodes resolved with only one operation in the PBC group. CT-guided percutaneous radiofrequency thermocoagulation and percutaneous balloon compression under local anesthesia may be good options for treating recurrent trigeminal neuralgia. Percutaneous balloon compression may be recommended when multiple branches are involved, particularly in cases of V1 neuralgia.

Diagnostic Accuracy of MRI in Detecting the Perineural Spread of Head and Neck Tumors: A Systematic Review and Meta-Analysis.

The purpose of this study was to review the diagnostic accuracy of MRI in detecting perineural spreading (PNS) of head and neck tumors using histopathological or surgical evidence from the afflicted nerve as the reference standard. Previous studies in the English language published in the last 30 years were searched from PubMed and Embase databases. We included studies that used magnetic resonance imaging (MRI) (with and without contrast enhancement) to detect PNS, as well as the histological or surgical confirmation of PNS, and that reported the exact numbers of patients required for assessing diagnostic accuracy. The outcome measures were sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Heterogeneity was assessed with the Higgins inconsistency test (I2). P-values smaller than 0.05 were considered statistically significant. A total of 11 retrospective studies were found, reporting 319 nerve samples from 245 patients. Meta-analytic estimates and their 95% confidence intervals were as follows: sensitivity 0.85 (0.70-0.95), specificity 0.85 (0.80-0.89), PPV 0.86 (0.70-0.94), and NPV 0.85 (0.71-0.93). We found statistically significant heterogeneity for sensitivity (I2 = 72%, p = 0.003) and PPV (I2 = 70%, p = 0.038), but not for NPV (I2 = 65%, p = 0.119) or specificity (I2 = 12%, p = 0.842). The most frequent MRI features of PNS were nerve enlargement and enhancement. Squamous cell carcinoma and adenoid cystic carcinoma were the most common tumor types, and the facial and trigeminal nerves were the most commonly affected nerves in PNS. Only a few studies provided examples of false MRI diagnoses. MRI demonstrated high diagnostic accuracy in depicting PNS of cranial nerves, yet this statement was based on scarce and heterogeneous evidence.

Acupuncture and moxibustion treatment of a child with primary trigeminal neuralgia: A case report

Primary Trigeminal Neuralgia (PTN) is a paroxysmal severe pain that occurs in the distribution area of the trigeminal nerve in the head, face, and oral cavity, which is more common in middle-aged and elderly people. Acupuncture is a traditional Chinese medical practice in which "treating internal diseases externally" is employed, and it refers to the use of both acupuncture and moxibustion. It has been reported in many literatures that acupuncture is effective in treating primary trigeminal neuralgia with few adverse reactions. This article reports on the case of a 9-year-old child with primary trigeminal neuralgia who, after experiencing some effectiveness but significant adverse reactions while using carbamazepine, was treated with acupuncture and moxibustion, resulting in a complete cure.

Fully endoscopic far-lateral supracerebellar infratentorial approach for trigeminal neuralgia: illustrative case reports

BackgroundTrigeminal neuralgia (TN) is a common cause of craniofacial pain. The retrosigmoid approach is usually used to treat TN, but no cases of endoscopic far-lateral supracerebellar infratentorial approach (EF-SCITA) were used to undergo operation for TN.Case presentationTwo patients were presented with severe facial pain and preliminary diagnosis was TN. Preoperative magnetic resonance imaging revealed that a superior cerebellar artery (SCA) compressed the trigeminal nerve in case 1, and a tumor located in the petrous apex extending into the Meckel’s cave compressed the trigeminal nerve in case 2. Operations were achieved through the EF-SCITA. The pain was totally relieved with no postsurgical complications in both cases.ConclusionsWe present the first two case reports of EF-SCITA to relieve classical and secondary TN successfully. The EF-SCITA can be a promising approach for treating TN.

Transposition versus interposition method in microvascular decompression for trigeminal neuralgia: midterm analysis of both techniques in a single-center study.

Operative interposition of material between the trigeminal nerve and offending artery for surgical treatment of drug-resistant trigeminal neuralgia (TGN), following the Jannetta method, has been proven to be the most successful invasive treatment. Reexplorations of patients with recurrence of TGN have revealed nerve root irritations and scarring due to interposed material. To prevent these complications, modifications of microvascular decompression (MVD) aim at transposing the vessel away from the trigeminal nerve, without attachment of additional material to the nerve root. Given that both techniques (interposition and transposition) have been performed in the authors' institution, they decided to analyze them for the short- and midterm outcomes. All patients who had undergone MVD for drug-resistant TGN in the authors' institution between 2008 and 2022 were analyzed retrospectively. Outcome at discharge and follow-up was evaluated using the Barrow Neurological Institute pain intensity score. Additionally, complications and pain recurrence were assessed. A total of 114 patients were operated on using transposition and 110 patients were treated using interposition. For transposition 102 patients were followed up for a median of 31.5 months, and for interposition 100 patients were followed up for a median of 95 months. At discharge 92.1% versus 94.5% of patients in the transposition and interposition groups, respectively, experienced a good outcome (Barrow Neurological Institute pain intensity scores I-III). At follow-up, 83.3% versus 85% of patients in the transposition and interposition groups, respectively, continued to demonstrate a good outcome. In 4.9% of patients in the transposition group and in 6% of patients in the interposition group, recurrence of pain occurred. Complications occurred in 24.6% of patients in the transposition and in 27.3% of those in the interposition group. The most frequent complications were facial hypesthesia (10.5% vs 11.8%, transposition vs interposition), followed by CSF leaks (2.6% vs 8.2%). Transposition for MVD is an elegant way of solving vessel-nerve conflicts at the cerebellopontine angle. Similar to interposition, transposition shows positive short- and midterm outcomes for patients experiencing drug-resistant TGN. However, the main objective of transposition, which is improved prevention of recurrence and reduction of complications at the trigeminal nerve, could not be confirmed in this study.

Optogenetics Neuromodulation of the Nose.

Recently developed optogenetic technology, which allows high-fidelity control of neuronal activity, has been applied to investigate the neural circuits underlying sensory processing and behavior. The nasal cavity is innervated by the olfactory nerve and trigeminal nerve, which are closely related to common symptoms of rhinitis, such as impairment of smell, itching, and sneezing. The olfactory system has an amazing ability to distinguish thousands of odorant molecules at trace levels. However, there are many issues in olfactory sensing mechanisms that need to be addressed. Optogenetics offers a novel technical approach to solve this dilemma. Therefore, we review the recent advances in olfactory optogenetics to clarify the mechanisms of chemical sensing, which may help identify the mechanism of dysfunction and suggest possible treatments for impaired smell. Additionally, in rhinitis patients, alterations in the other nerve (trigeminal nerve) that innervates the nasal cavity can lead to hyperresponsiveness to various nociceptive stimuli and central sensitization, causing frequent and persistent itching and sneezing. In the last several years, the application of optogenetics in regulating nociceptive receptors, which are distributed in sensory nerve endings, and amino acid receptors, which are distributed in vital brain regions, to alleviate overreaction to nociceptive stimuli, has gained significant attention. Therefore, we focus on the progress in optogenetics and its application in neuromodulation of nociceptive stimuli and discuss the potential clinical translation for treating rhinitis in the future.

Features of olfactory impairment connected with trigeminal nerve system

Qualitative assessment of olfactory disorders after COVID-19 according to the system of olfactory and trigeminal nerves with a targeted assessment of the functional component of olfactory disorders. We examined 40 patients aged 19 to 66 who had a coronavirus infection. All patients underwent neurological, otorhinolaryngological examinations, olfactometry, filled out the hospital anxiety and depression scale. Anosmia was diagnosed in 5 (12.5%) patients, hyposmia in 21 (52.5%) patients, and normosmia in 14 (35%) patients. Formed: the 1st group - 14 patients (35%) with normogram according to olfactometry; the 2nd group - 26 patients (65%) with anosmia/hyposmia. In the 1st group, disorders of the anxiety-depressive spectrum were significantly more common. In the 2nd group, a low identification of odors was found, lying in the spectrum of fresh, sharp, unpleasant, irritating, compared with sweet and pleasant or neutral, which indicates a predominant lesion of the trigeminal system. In patients with complaints of impaired sense of smell after undergoing COVID-19, the possible functional nature of anosmia/hyposmia should be taken into account, which requires the referral of such patients to psychotherapeutic specialists, and the possible entry of olfactory disorders into the 'trigeminal' spectrum.

Особливості ураження трійчастого нерва при стоматологічних захворюваннях: надання невідкладної допомоги

Summary. Usually, the clinical basis of neurostomatological diseases is the lesion of various parts of the nervous system that provide innervation of the oral cavity and face. The main nerves whose damage leads to the development of neurostomatological diseases are the trigeminal, facial, intermediate, lingual, vagus and hyoid nerves. Among them, the trigeminal nerve system is most often affected. The causes can be odontogenic diseases such as pathological processes of the dentition and ineffective or incorrect methods of their treatment (traumatic complex tooth extraction, including the presence of bone fragments, root remnants in the socket, pulpitis and periodontitis, galvanisation phenomena when using various methods for filling and prosthetics, poorly made dentures, gingivitis, etc.) In the lecture, we tried to highlight the lesions of the trigeminal nerve system in dental diseases, emergency care, treatment and rehabilitation. Key words: trigeminal neuralgia, dental diseases, emergency care.

CHANGES IN THE WIDTH OF THE PERIODONTAL GAP OF RATS WITH SUPRAOCCLUSAL RELATIONSHIPS OF INDIVIDUAL TEETH IN THE AGE ASPECT

Introduction. The dentoalveolar apparatus is a complex of complicated interaction of the jaws, masticatory muscles, teeth, and temporomandibular joints. This connection is carried out by the trigeminal nerve system with sensory and motor nuclei closely connected to the cortical and subcortical centers of the brain. Occlusal trauma is a lesion that develops in the periodontium as a result of forces that exceed the periodontal potential for functional adaptation. Occlusal trauma can be classified as primary or secondary. The first one occurs in the pulp and periodontal ligament when the force of the action on the dental structures is greater than usual, under optimal periodontal support conditions. It includes orthodontic movements, "high" restorations, and parafunctional habits such as bruxism. Secondary occlusal trauma occurs when the teeth with previous supporting tissue changes are subjected to the action of normal and excessive forces with supporting tissue changes caused by periodontal disease or previous trauma. The available evidence has demonstrated that bacterial plaque bioactive substances lead to local inflammatory responses in periodontal tissues which contribute to bone tissue resorption through osteoclasts in periodontitis. Excessive functional stress can initiate inflammatory changes in the periodontium and thus, increase destructive bacterial processes. Traumatic occlusion can expand the space of the periodontal ligament and in this way stimulate apical bacterial migration and proliferation. However, few attempts have been made to investigate the molecular mechanisms that trigger bone tissue resorption in traumatic occlusion. The analysis of publications on the studies of morphological changes in periodontal tissues in individual teeth supraocclusion in the age aspect shows the contradictory data. The aim: to determine the morphometric changes of the periodontal gap as a component of the periodontal complex in rats of different age groups in the supraocclusal relationship of individual teeth in the age aspect. Materials and methods of the study. The scientific experiment was conducted on 60 white laboratory rats aged 4 to 22 months and weighing 90 to 330 g. The rats were divided into control (30 animals) and experimental (30 animals) groups. Each group was divided into 3 subgroups (10 animals each) depending on the age of the rats: young, mature and senile. Young animals included rats aged 3–4 months with a weight of 90–100 g; mature animals - aged 6–8 months with a weight of 150–170 g; senile rats – 20–22 months and weighing 200–220 g. The method of modelling the state of supraocclusal relations of individual teeth is described in the previous publication. For histological examination of dental blocks, the following was performed. Fixation in a 10% solution of neutral formalin for two days, dehydration in alcohols of increasing concentration and embedding in paraffin. After preparation, sections were made on a Shandon Finesse 325 rotary microtome with a section thickness of 4-6 µm. The histological sections were fixed on pre-degreased slides and dried. Van Gieson staining was performed. The width of the periodontal gap was determined using the ZEISS ZEN 3.7 program by Carl Zeiss Microscopy. For statistical data processing, the AtteStat v.12.5 software was used to determine the mean value and its standard error (M±m). The probability of a statistically significant difference between the data obtained was assessed using the Student's parametric test (at a significance level of p ≤ 0.05). All samples were tested for normality using the Gupta test. Results of the study. Statistical differences were observed in rats of all groups, as well as between the indicators of all rats of the control and experimental groups (≤0.05). The width of the periodontal gap increased by 34.1% in young rats, by 25.5% in mature rats, and by 21.1% in senile rats. Conclusions The presence of supraocclusal relationships of individual teeth causes an increase in the periodontal gap in rats of all age groups. The greatest expansion of the periodontal gap has occurred in young rats. The width of the periodontal gap in rats decreases with age.

Mitochondria-targeting nanozyme alleviating temporomandibular joint pain by inhibiting the TNFα/NF-κB/NEAT1 pathway.

Inflammatory cytokines that are secreted into the spinal trigeminal nucleus caudalis (Sp5C) may augment inflammation and cause pain associated with temporomandibular joint disorders (TMD). In a two-step process, we attached triphenylphosphonium (TPP) to the surface of a cubic liposome metal-organic framework (MOF) loaded with ruthenium (Ru) nanozyme. The design targeted mitochondria and was designated Mito-Ru MOF. This structure scavenges free radicals and reactive oxygen species (ROS) and alleviates oxidative stress. The present study aimed to investigate the effects and mechanisms by which Mito-Ru MOF ameliorates TMD pain. Intra-temporomandibular joint (TMJ) injections of complete Freund's adjuvant (CFA) induced inflammatory pain for ≥10 d in the skin areas innervated by the trigeminal nerve. Tumor necrosis factor-alpha (TNF-α), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), long non-coding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1), and ROS also have been proved to be significantly upregulated in the Sp5C of TMD mice. Moreover, a single Mito-Ru MOF treatment alleviated TMD pain for 3 d and downregulated TNF-α, NF-κB, lncRNA NEAT1, and ROS. NF-κB knockdown downregulated NEAT1 in the TMD mice. Hence, Mito-Ru MOF inhibited the production of ROS and alleviated CFA-induced TMD pain via the TNF-α/NF-κB/NEAT1 pathway. Therefore, Mito-Ru MOF could effectively treat the pain related to TMD and other conditions associated with severe acute inflammatory activation.

Facial Onset Sensory and Motor Neuronopathy with Neurotrophic Keratitis: A Case Report

Facial-onset sensory and motor neuronopathy (FOSMN) is a rare, progressive neurodegenerative disorder characterized by sensory loss and motor deficits, primarily affecting the face and upper extremities. The condition begins with sensory impairments in the trigeminal nerve distribution, extending to involve the scalp, neck, upper limbs, and trunk. Symptoms include facial weakness, bulbar disturbances (dysphonia, dysarthria, dysphagia, and sialorrhea), and lower motor neuron signs (weakness, atrophy, fasciculation, and cramps) in the limbs. A hallmark of FOSMN is the diminished or absent corneal reflex, indicating trigeminal nerve involvement and leading to potential complications like neurotrophic keratitis (NK), which can cause corneal ulceration and blindness. The etiology of FOSMN remains uncertain, with theories proposing autoimmune or neurodegenerative origins. Diagnosis is challenging due to the overlap with other ocular surface disorders, necessitating careful examination and differential diagnosis. Management focuses on symptomatic relief, including eye protection to prevent corneal complications. Awareness and early detection of ocular symptoms in FOSMN are crucial for preventing severe outcomes like NK and blindness.

Неврологические осложнения в косметологии: обзор литературы

INTRODUCTION. The article discusses complications from the nervous system during such cosmetic procedures as botulinum therapy, the use of fillers, mesotherapy and thread lifting. AIM. Conduct an analysis of literary sources of domestic and foreign authors describing the modern understanding of neurological complications that arise in cosmetology practice. MATERIAL AND METHODS. An analysis of literature in Russian and English was carried out for the period from 2013–2024. Sources from the Russian scientific electronic library eLIBRARY, RSCI databases, and PubMed were used. RESULTS AND DISCUSSION. One of the most common neurological side effects of botulinum toxin is paralysis of the facial and masticatory muscles, innervated by the facial and trigeminal nerves, respectively. The mechanism of the negative effect of fillers on nervous tissue is associated, first of all, with their composition, which can have a toxic effect. During filler injections, nerve fibers can be damaged, which leads to disruption of the transmission of nerve impulses. The literature describes cases of deterioration or even loss of monocular vision, ptosis and ophthalmoplegia after injection of hyaluronic acid filler. A complication when using fillers based on hyaluronic acid and autologous fat is acute cerebrovascular accident. Prevention of neurological complications during cosmetic procedures is an important aspect of safety and successful results in aesthetic medicine.CONCLUSION. Neurological complications can occur as a result of various cosmetic procedures. The main factors are technique, lack of understanding of facial anatomy, and the use of low-quality drugs. It is important to be aware of the potential risks and contact only experienced specialists to reduce the likelihood of neurological complications. KEYWORDS: fillers, botulinum therapy, thread lifting, neurological complications, facial nerve neuropathy

Neural regulation of mesenchymal stem cells in craniofacial bone: development, homeostasis and repair.

Mesenchymal stem cells endow various functions, including proliferation, multipotency, migration, etc. Craniofacial bones originate from the cranial neural crest and are developed mainly through intramembranous ossification, which are different from long bones. There are varied mesenchymal stem cells existing in the craniofacial bone, including Gli1 + cells, Axin2 + cells, Prx1 + cells, etc. Nerves distributed in craniofacial area are also derived from the neural crest, and the trigeminal nerve is the major sensory nerve in craniofacial area. The nerves and the skeleton are tightly linked spatially, and the skeleton is broadly innervated by sensory and sympathetic nerves, which also participate in bone development, homeostasis and healing process. In this review, we summarize mesenchymal stem cells located in craniofacial bone or, to be more specific, in jaws, temporomandibular joint and cranial sutures. Then we discuss the research advance concerning neural regulation of mesenchymal stem cells in craniofacial bone, mainly focused on development, homeostasis and repair. Discovery of neural regulation of mesenchymal stem cells may assist in treatment in the craniofacial bone diseases or injuries.

The methodology for diagnosing and managing stress developed by Grivtsova, as an independent method and as part of the preparation for inducing lucid dreams within the framework of the “Bancheko Extended Algorithm,” and its application in the “Global Forecasting System,” serves as a means of transferring transcendental states of consciousness within the “Bancheko-Technology Set”

According to the World Health Organization (WHO), the increase in stressful situations due to the accelerating pace of life, environmental pollution, urbanization, technological progress, and low socio-economic living standards of the population, underpins the rise in neurological diseases. Consequently, one of the crucial tasks in practical psychology and applied psychophysiology is the timely and comprehensive diagnosis and correction of borderline forms of psychological disorders. This study examines the application of stress diagnosis and correction methodologies. The foundation is the wave model of brain electrical activity, observed using electroencephalography, based on an algorithm developed during the experiment. The key hypothesis of the study suggests that by following the developed self-organization system, based on performing simple actions, individuals with disrupted brain electrical activity due to various stressors can avoid pharmacological interventions. It has been shown that the consequences of stress primarily include increased tension in the central nervous system (sympathetic component) and insufficient relaxation (parasympathetic component). During the exacerbation of chronic diseases, the following effects were observed in subjects: poor sleep in patients with gastritis, drowsiness and headaches in individuals with allergies, chronic migraines, and neurological pains in the head on the left side along the trigeminal nerve, meteorological dependence in hypertensive patients, and jaw locking and right-side pain in those with traumatic brain injuries. Correction of these disorders took into account their stress-induced nature. A method for rehabilitating emotional-affective disorders in individuals is proposed to overcome stressful situations. The obtained data suggest that the proposed method of restorative alpha rhythm through neurotraining has high potential in therapeutic work for overcoming and correcting stress in people from various social groups, ages, and professions.

Correlation between fluoride release, surface hardness and diametral tensile strength of restorative glass ionomer cements.

A complete and thorough understanding of head and neck anatomy by dental hygienists is fundamental for performing successful dental hygiene procedures in all clinical settings. Therefore, the aim of the present study was to assess the opinion of a population of dental hygiene students about the educational methods, their perceptions of the tooth drawing module, and their opinion about the content of Anatomy curriculum in an Italian University. A comprehensive survey about was developed and electronically distributed to the dental hygiene students. The questionnaire consisted of questions on the application of anatomical knowledge in clinical practice, opinions on the contents and methods of gross anatomy education, and opinions on the tooth drawing module. The survey was completely answered by 63 respondents. According to most respondents, drawing exercises helped to better understand the anatomy of the teeth, to incorporate dental anatomy more effectively, and to improve their ability to visualize tooth anatomy. Most respondents reported that molars were the most difficult teeth to be drawn. The respondents gave the maximum importance to the anatomical knowledge of the mandible, the maxilla, the masticatory muscles, the temporomandibular joint, the palate, the tongue, the salivary glands, the trigeminal nerve, and the facial nerve. Dental drawing exercises seem to be extremely important for Dental Hygiene Bachelor Degrees and they are well appreciated by students. Appropriate educational methods of anatomy should be used to improve the attention and the learning by dental hygiene students, thus finally hopefully resulting in the improvement of their clinical skills. Key words:Dental hygiene, anatomy, drawing, teeth, education.

Microvascular Decompression for Trigeminal Neuralgia Caused by Trigeminocerebellar Artery

The trigeminocerebellar artery(TCA)is a unique branch of the basilar artery. The TCA was first described in detail by Markovic et al. in 1996. The incidence of TCA was 6.9%-13.3% in previous cadaveric studies. The TCA branches from the distal part of the basilar artery, courses very close to the trigeminal nerve root entry zone, and occasionally twists or encircles the nerve root. A close relationship between the TCA and trigeminal nerve can cause trigeminal neuralgia(TN). This characteristic course of TCA requires adjuvant decompression techniques performed by the operators. In the microvascular decompression for TN caused by the TCA, operators should pay attention to the following: 1)sufficient arachnoid dissection around the TCA, 2)combined transposition and interposition technique, 3)decompression of perforators and vessels penetrating the nerve, and 4)recognition of the existence of the TCA.

History of Trigeminal Neuralgia:Before the Era of Modern Treatment

Descriptions of what appears to be trigeminal neuralgia(TN)appear in medical literature from around the 2nd century AD. Aretaeus of Cappadocia is believed to be the first person in history to have specifically described TN. TN or TN-like facial pain was once known as Fothergill's disease, following a detailed description of the symptoms by Fothergill in the 18th century. For a long time, no effective oral therapy for TN was available, and only surgical treatments were used, such as severing of the trigeminal nerve or resection of the Gasserian ganglion. In the 19th and 20th centuries, Hartley, Krauss, Cushing, Spiller and Frazier developed techniques for approaching the Gasserian ganglion through the middle cranial fossa, and Dandy pioneered trigeminal nerve transection through the posterior fossa. Also at this time, Harris introduced nerve block using alcohol. Later, various oral medications, such as phenytoin(1942)and carbamazepine(1962), were introduced and these became effective treatments. Modern surgical treatment began in the mid-20th century, when Taarnhøj, Gardner and Jannetta introduced nerve decompression.

Intrinsic trigeminal nerve arteriovenous malformation: a rare cause of trigeminal neuralgia

Intrinsic trigeminal nerve arteriovenous malformation is an exceptional cause of trigeminal neuralgia. Imaging is not only important for visualising the nidus, but should also precise feeding arteries and draining veins, which are very variable in this location. Magnetic resonance imaging provides the spatial resolution required to show the relation of the nidus with the trigeminal nerve, by using adapted sequences for vascular and neurological structures assessment. Digital subtraction angiography remains the gold-standard imaging technic for showing the angioarchitecture of the arteriovenous malformation, proving its superiority to computed tomography angiography. In this article, we report the case of a 77 years-old woman with trigeminal neuralgia secondary to an intrinsic trigeminal nerve arteriovenous malformation with unusual venous drainage, diagnosed by an MRI of the cerebellopontine angle, with the assessment of its angioarchitecture on CTA.

Autonomic features of craniofacial neuralgias: a systematic review with meta-analysis

The aim of the study is to describe the severity, temporal characteristics, and types of autonomic features as they relate to the characteristics of pain of the neuralgias. Also, to describe, based on literature, how these autonomic features can affect the treatment outcomes of patients with craniofacial neuralgias. We carried out a literature search using five databases, PubMed, Embase, OVID, Scopus and Web of Science. The search was executed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The protocol for this systematic review and meta-analysis was registered on PROSPERO CRD42021235319. 40% of all patients with craniofacial neuralgias had at least one autonomic feature. Out of the craniofacial neuralgias, trigeminal neuralgia was the most reported, with lacrimation being the most prevalent concomitant autonomic feature. There was also differences in the occurrence of the autonomic features dependent on which branch of a nerve such as the trigeminal nerve, was afflicted. When trigeminal neuralgia is excluded, the rest of the craniofacial neuralgias had reported autonomic features 28% of the pain events. (95% Confidence Interval: 2–90%). Contrary to the conventional belief, we found certain autonomic features to be more predominant than others, in specific craniofacial neuralgias. The prevalence of the autonomic features for all craniofacial neuralgias in the descending order is as follows, lacrimation, conjunctival injection, nasal congestion, rhinorrhea, flushing, edema/swelling, salivation, ptosis and sweating. With trigeminal neuralgia, the most common autonomic feature was lacrimation, and the least common was nasal congestion.

4-Phenyl-thiazole-based dual inhibitors of fatty acid amide hydrolase and soluble epoxide hydrolase do not alleviate orofacial inflammatory pain in female rats

Pain arising from trigeminal systems such as headache is common, debilitating, and current treatments (e.g., sumatriptan) are limited. New treatments that target novel mechanisms of action may be required to innovate both short- and long-term pain therapy. Fatty acid amide hydrolase and soluble epoxide hydrolase are two pain-related enzymes that regulate pain and inflammation via independent pathways. We have previously demonstrated that simultaneous inhibition of these enzymes using a novel dual inhibitor alleviates acute inflammatory pain in the hindpaw and does not depress wheel running in rats. Here, we expanded on these findings and performed structure-activity relationships of our lead compound, the 4-phenyl-thiazole-based dual inhibitor SW-17, to generate 18 analogs and tested them for their inhibition at both enzymes. Conversion of the sulfonamide group to a tertiary amine led to a general decrease in the potency for the sEH enzyme, while this change was well-tolerated at the FAAH enzyme yielding several strong inhibitors. Six selected inhibitors were evaluated in mouse and rat sEH inhibition assays and results showed a species difference, i.e. 4-phenyl-thiazole-based analogs are significantly less or not active in mouse sEH compared to human and rat enzymes. The most potent inhibitor, SW-17, was evaluated in a plasma stability assay in human and rat plasma and showed moderate stability. However, SW-17 did not alleviate orofacial inflammatory pain in female rats compared to the traditional anti-migraine agent sumatriptan. Although modification of 4-phenyl-thiazole-based dual inhibitor SW-17 changes potencies at both FAAH and sEH, these approaches may not produce antinociception against trigeminal pain. Key Words: polypharmacology, formalin, inflammation, enzyme inhibition, structure-activity relationship studies