Familial trigeminal neuralgia

Familial occurrence of classical and idiopathic trigeminal neuralgia

Trigeminal neuralgia (TN) is a severe facial pain disease with unknown pathogenesis. It has been thought that the familial form of TN is rare with a prevalence of about 1-2% among affected individuals, but emerging evidence suggests a role of genetic factors. This study examined the occurrence of familial TN among patients with classical or idiopathic TN. Patients with TN recruited from a hospital registry received an informed consent form with a questionnaire, and individuals reporting other family members with TN underwent a structured phone-interview. For affected family members, type of TN, available clinical, imaging, management results and available hospital patient records were studied. Pedigrees for all affected families were established. This study included 268 patients with either classical or idiopathic TN. The familial form of TN was present in 41/268 (15.3%) patients, that is, 37/244 (15.2%) patients with classical TN and in 4/24 (16.7%) with idiopathic TN. Total 38 families were identified, with two affected members in 32/38 families (84.2%), three affected family members in 5/38 (13.2%) and four family members in 1/38 (2.6%) families. Comparing the 41 familial TN cases with the 227 sporadic TN patients showed significantly earlier onset of TN and a significantly higher occurrence of right-sided pain in familial cases, while there was no difference in gender distribution, occurrence of arterial hypertension or trigeminal branch involved. Among patients with classical or idiopathic TN, the occurrence of the familial form of the disease is more frequent than traditionally assumed.

Trigeminal neuralgia and genetics: A systematic review

Trigeminal neuralgia (TN) is a severe facial pain disease of unknown cause and unclear genetic background. To examine the existing knowledge about genetics in TN, we performed a systematic study asking about the prevalence of familial trigeminal neuralgia, and which genes that have been identified in human TN studies and in animal models of trigeminal pain. MedLine, Embase, Cochrane Library and Web of Science were searched from inception to January 2021. 71 studies were included in the systematic review. Currently, few studies provide information about the prevalence of familial TN; the available evidence indicates that about 1–2% of TN cases have the familial form. The available human studies propose the following genes to be possible contributors to development of TN: CACNA1A, CACNA1H, CACNA1F, KCNK1, TRAK1, SCN9A, SCN8A, SCN3A, SCN10A, SCN5A, NTRK1, GABRG1, MPZ gene, MAOA gene and SLC6A4. Their role in familial TN still needs to be addressed. The experimental animal studies suggest an emerging role of genetics in trigeminal pain, though the animal models may be more relevant for trigeminal neuropathic pain than TN per se. In summary, this systematic review suggests a more important role of genetic factors in TN pathogenesis than previously assumed.

Molecular mechanisms of trigeminal neuralgia: A systematic review

OBJECTIVE

To conduct a systematic review of the available literature for primary research articles identifying potential gene mutations, polymorphisms and other molecular regulatory mechanisms related to trigeminal neuralgia in order to identify the genetic and molecular models of primary trigeminal neuralgia currently being investigated.

METHODS

PubMed and Web of Science were systematically searched to identify primary research articles discussing genetic predictors of trigeminal neuralgia and neuropathic pain that were published prior to July 2020. This review was conducted according to PRISMA guidelines.

RESULTS

Out of the 333 articles originally identified, a total of 14 papers were selected for study inclusion. These articles included 5 human studies, 6 mouse studies and 3 rat studies. Four articles investigated sodium channels, 1 investigated a sodium channel and nerve growth factor receptor, 2 investigated potassium channels, 1 investigated calcium channels, 1 investigated the downstream regulatory element antagonist modulator protein, 1 investigated the dynorphin-kappa opioid receptor system, 1 investigated TRPA1, 1 investigated the Nrg1/ErbB3/ErbB2 signaling complex, 1 investigated a serotonin transporter and 1 investigated potassium channels, sodium channels, calcium channels, chloride channels, TRP channels and gap junctions.

CONCLUSION

Researchers have identified multiple genetic and molecular targets involved with potential pathophysiologies that have a relationship to the creation of trigeminal neuralgia. At this time, there does not seem to be clear causal frontrunner, demonstrating the possibility that genetic predisposition to trigeminal neuralgia may involve multiple genes and/or downstream products, such as ion channels.

Trigeminal Neuralgia: Basic and Clinical Aspects

The trigeminal nerve is the largest of all cranial nerves. It has three branches that provide the main sensory innervation of the anterior two-thirds of the head and face. Trigeminal neuralgia (TN) is characterized by sudden, severe, brief, and stabbing recurrent episodes of facial pain in one or more branches of the trigeminal nerve. Pain attacks can occur spontaneously or can be triggered by non-noxious stimuli, such as talking, eating, washing the face, brushing teeth, shaving, a light touch or even a cool breeze. In addition to pain attacks, a proportion of the patients also experience persistent background pain, which along with autonomic signs and prolonged disease duration, represent predictors of worse treatment outcomes. It is now widely accepted that the presence of a neurovascular compression at the trigeminal root entry zone is an anatomic abnormality with a high correlation with classical TN. However, TN may be related to other etiologies, thus presenting different and/or additional features. Since the 1960s, the anticonvulsant carbamazepine is the drug of choice for TN treatment. Although anti-epileptic drugs are commonly used to treat neuropathic pain in general, the efficacy of carbamazepine has been largely limited to TN. Carbamazepine, however, is associated with dose-limiting side-effects, particularly with prolonged usage. Thus, a better understanding and new treatment options are urgently warranted for this rare, but excruciating disease.

Familial classic trigeminal neuralgia

INTRODUCTION

The classic form of trigeminal neuralgia is usually sporadic (no familial clustering). However, around 2% of all cases of trigeminal neuralgia may be familial. Describing this entity may be useful for diagnosing this process and may also be key to determining the underlying causes of sporadic classical trigeminal neuralgia. We report on cases in a series of 5 families with at least 2 members with classic trigeminal neuralgia, amounting to a total of 11 cases.

MATERIAL AND METHODS

We recorded cases of familial classical trigeminal neuralgia between March 2014 and March 2015 by systematically interviewing all patients with a diagnosis of trigeminal neuralgia who visited the neurology department on an outpatient basis.

RESULTS

In our sample, most patients with familial classic trigeminal neuralgia were women. Mean age at onset was 62.9±13.93 years, decreasing in subsequent generations. V2 was the most frequently affected branch. Most of our patients responded well to medical treatment, and surgery was not effective in all cases.

CONCLUSIONS

These family clusters support the hypothesis that classic trigeminal neuralgia may have a genetic origin. Several causes have been suggested, including inherited anatomical changes affecting the base of the skull which would promote compression of the trigeminal nerve by vascular structures, familial AHT (resulting in tortuous vessels that would compress the trigeminal nerve), and mutations in the gene coding for calcium channels leading to hyperexcitability. Classic trigeminal neuralgia may be an autosomal dominant disorder displaying genetic anticipation.

Familial Trigeminal Neuralgia Treated with Stereotactic Radiosurgery: A Case Report and Literature Review

Background

Trigeminal neuralgia (TN) is a chronic pain condition characterized by brief episodes of lancinating pain in one or more distributions of the trigeminal nerve. Episodes of pain secondary to TN are triggered by certain stimuli, such as chewing, shaving, or touching the face. Although a common cause of TN is compression of the trigeminal nerve root entry zone by an artery or vein, many cases of TN are idiopathic. However, there have been limited reports in the literature of familial TN.

Case Presentation

A 31-year-old male presented with classic TN symptoms in the right V1/V2 distribution that recently progressed to the V3 distribution a case of familial TN. His father an brother both have TN. Carbamazepine, oxcarbazepine, and rhizotomy did not improve his symptoms. He was treated with stereotactic radiosurgery (SRS) with a dose of 85 Gy delivered to the proximal trigeminal root with improvement in his pain. We also review and summarize the over 160 cases of familial TN found in the literature.

Conclusions

This is the first reported case of familial TN treated with SRS. Patients with familial TN are more likely to have bilateral disease, to present with earlier onset, and to become refractory to medical therapy and may require more aggressive approaches. We propose that SRS is a good treatment approach for these patients.

Trigeminal and glossopharyngeal neuralgia

Trigeminal neuralgia and glossopharyngeal neuralgia are two causes of paroxysmal craniofacial pain. Either can be debilitating in affected individuals. This article reviews the epidemiology, pathogenesis, diagnosis, and treatment options for these disorders.

[Familial trigeminal neuralgia]

Trigeminal neuralgia in its classic form is usually an isolated disease that occurs in sporadic fashion, but familial cases have been described. We report the case of a 45-year-old man who presented with left V2 trigeminal neuralgia. The neurological examination was normal and imaging and laboratory investigations were non-contributive to the etiological work-up. Carbamazepine gave excellent symptomatic relief. During patient evaluation, we became aware of a clustering of trigeminal neuralgia in four other family members over three generations. Familial trigeminal neuralgia has been expounded on in fewer than 30 reports in the literature. Our cases and the literature review suggest an autosomal dominant transmission. The clinical features of familial trigeminal neuralgia are described and pathophysiological implications of this genetic clustering discussed.

Idiopathic familial trigeminal neuralgia: a case report

Trigeminal neuralgia (TN) is paroxysmal, lancinant pain often described as an "electric wave" by patients, with involvement of the divisions of the fifth cranial nerve. Demyelinating, compressive, ischaemic diseases are involved in the physiopathology of TN, but there are some cases without explanation. Familial TN (FTN) is a rare condition, about 1%-2% of all TN cases, while sporadic cases are the most common. To date, there have been about 126 reports of FTN. We describe the case of a 66-year-old man who had been complaining for 3 years of right-side paroxysmal lancinating pain in the second division of the fifth cranial nerve. A brain MRI with angiographic sequences did not show neurovascular conflicts or other pathological conditions. The patient had a family history of TN, which had been diagnosed in 3 other family members (father, sister and first cousin), who had undergone medical or surgical treatment for TN. There was no family history of hypertension, metabolic disorders, neurological or traumatic diseases. Animal studies have shown a probable involvement of genes codifying for calcium channels as the starting alterations in trigeminal excitability. Our FTN could be a good model to investigate the role of gene mutations in this condition.

Trigeminal neuralgia

Trigeminal Neuralgia (TN) is a well recognized syndrome characterized by lancinating attacks of severe facial pain. The diagnosis of TN is based on a history of characteristic pain attacks that are consistent with specific widely accepted criteria for the diagnosis. TN pain attacks may result from physiologic changes induced by a chronic partial injury to the brainstem trigeminal nerve root from a variety of causes. An early and accurate diagnosis of TN is important, because therapeutic interventions can reduce or eliminate pain attacks in the large majority of TN patients.

Familial trigeminal neuralgia: case reports and review of the literature

The paroxysmal facial pain of trigeminal neuralgia is usually idiopathic, but familial cases have been described. We describe a family with apparent autosomal dominant transmission of trigeminal neuralgia. Our cases and a review of the literature suggest that the etiology of trigeminal neuralgia may be vascular compression of the fifth cranial nerve. Autosomal dominant vascular and epileptic disorders are reviewed, and possible relationships to familial trigeminal neuralgia are considered.

Familial trigeminal neuralgia. Case report and review of the literature

The authors report the case of a 45-year-old woman with medically intractable trigeminal neuralgia (TN) in whom a good clinical response to partial sectioning of the trigeminal nerve was attained. No evidence of vascular compression was found intraoperatively. Several other members of her family, involving three generations, also suffered from TN. The treatment of all affected patients is discussed in the context of a literature review in which the controversies surrounding the origins of the disease and treatment options for patients with the familial variant of TN are addressed.

Familial trigeminal neuralgia and Charcot-Marie-Tooth neuropathy. Report of two families and review

Typical trigeminal neuralgia has occasionally occurred in multiple members of the same family over several generations. The clinical features of such cases, including the increased incidence in females, and the absence of other apparent hereditary, neurologic, metabolic, or structural abnormalities were identical to those of sporadic cases. More rarely, familial trigeminal neuralgia has been described in the setting of hereditary peripheral neuropathy, especially Charcot-Marie-Tooth disease. We describe patients from two different families with Charcot-Marie-Tooth disease and medically intractable trigeminal neuralgia. Both patients were successfully treated by percutaneous retrogasserian glycerol rhizolysis. The occurrence of cranial nerve symptoms in patients with demyelinating peripheral neuropathies is discussed in light of the current hypotheses regarding the etiology of trigeminal neuralgia.

Incidence and clinical features of trigeminal neuralgia, Rochester, Minnesota, 1945-1984

The overall crude incidence rate of trigeminal neuralgia per 100,000 population in Rochester, Minnesota, for 1945 through 1984 was 4.3 for both sexes combined. The age-adjusted (to total 1980 US population) rate for women (5.9) was significantly higher than that for men (3.4). Annual incidence rates increased significantly with age in both women and men. Data based on evidence in the medical records suggest that trigeminal neuralgia is a rather rare and unpredictable disease: The number of episodes varies from 1 to 11, and length of episode from 1 day to 4 years. This study indicates an elevated relative risk associated with hypertension (both overall and among women in the cohort). Also, prevalence of multiple sclerosis was significantly greater among the group of 75 patients who had trigeminal neuralgia. Since the data on treatment in this study do not correspond to a randomized clinical trial, they are presented as empirical results only and show no single treatment of choice for trigeminal neuralgia.

Bilateral trigeminal neuralgia: a 14-year experience with microvascular decompression

Thirty-five patients with trigeminal neuralgia (TN) bilaterally underwent posterior fossa microvascular decompression (MVD) between 1971 and 1984. They comprised 5.0% of a larger series of 699 patients with TN who underwent MVD during that interval. Compared to the subgroup of 664 patients with only unilateral symptoms, the population with bilateral TN included a greater percentage of females (74% vs. 58%, p less than 0.1), a higher rate of "familial" TN (17% vs. 4.1%, p less than 0.001), and an increased incidence of additional cranial nerve dysfunction (17% vs. 6.6%, p less than 0.05) and hypertension (34% vs. 19%, p less than 0.05). Of the 35 patients with bilateral TN, 10 underwent bilateral MVD (22 procedures) and 25 underwent unilateral MVD (30 procedures). In the latter patients, pain on the nonoperative side was well controlled with medication alone or had previously been treated by ablative procedures. Good or excellent pain control was achieved after one MVD was performed in 40 of the 45 sides treated (89%), and was maintained 1, 5, and 10 years after surgery in 82%, 66%, and 60%, respectively, based on life-table analysis. Six of 10 patients with recurrent symptoms underwent repeat unilateral MVD. Good or excellent long-term pain control was maintained in all six. With these repeat procedures included, symptom control at 1, 5, and 10 years after initial surgery was maintained in 87%, 78%, and 78% of the treated sides, respectively. Overall, 26 of 35 patients (74%) maintained good or excellent pain relief throughout the duration of the study (mean follow-up period 75 months) without resumption of regular medication usage. Although preoperative neurological deficits resulting from previous ablative procedures were seen in the majority of patients before MVD, no patient developed new major trigeminal sensory loss or masseter weakness after MVD. Operative mortality was zero. The results indicate that posterior fossa MVD is an effective and relatively safe treatment for the majority of patients with bilateral "idiopathic" TN, avoiding the risks of bilateral trigeminal nerve injury seen with other approaches.