Sex, Gender, and Orofacial Pain.

This review examines gender prevalence in orofacial pain to elucidate underlying factors that can explain such differences. This review highlights how gender affects (1) the association of hormonal factors and pain modulation; (2) the genetic aspects influencing pain sensitivity and pain perception; (3) the role of resting blood pressure and pain threshold; and (4) the impact of sociocultural, environmental, and psychological factors on pain.

Analgesic efficacy and safety of medical therapy alone vs combined medical therapy and extraoral glossopharyngeal nerve block in glossopharyngeal neuralgia.

OBJECTIVE: The aim of this study is to compare medical therapy alone and medical therapy with add on extraoral glossopharyngeal nerve block in terms of analgesic efficacy and hemodynamic safety in patients with glossopharyngeal neuralgia (GPN). As GPN is a rare disease, our secondary targets were to review the demographic profile of the disease, clinical profile, and any associations with the disease. DESIGN: This was a randomized, prospective, active-controlled, parallel group study conducted from 2007 to 2009 to determine the safety and efficacy of extraoral glossopharyngeal nerve block in GPN and compare it with pharmacological intervention. After institutional ethics committee approval and patient's consent, GPN patients were randomly allocated into two groups. Group A (N = 15) received standard medical therapy (gabapentin 300 mg, tramadol 50 mg TDS, methylcobalamin 500 µgm PO) and group B (N = 15) patients received extraoral glossopharyngeal nerve block together with standard medical therapy. Patients were analyzed for analgesic outcome using numerical pain scale (NPS) and brief pain inventory (BPI) assessing both analgesic effect and degree of interference in quality of life (QOL) during 3-month follow-up. They were also evaluated for any significant hemodynamic alterations. RESULTS: Over the follow-up of 90 days, the mean NPS in group A decreased from 6 ± 2 to 3 ± 2 and in group B from 5 ± 1 to 2 ± 2. From the mean NPS scores, it can be interpreted that both the modalities were effective clinically in treating GPN. However, NPS scores were statistically similar by the end of 90 days. Improvement from baseline in BPI measurement of QOL (mood, interpersonal relationship, and emotion) was earlier in group B (1, 2, and 1 months, respectively) compared with group A (2, 3, and 2 months, respectively). However, there were no significant hemodynamic adverse outcomes after administration of the block. CONCLUSION: This study found that patients in both the groups had significantly lower pain intensities, improved pain relief, and reduced pain interference with QOL, which was especially evident on fourth visit (2 months) after the initiation of treatment regimen. Both were safe and well tolerated. The study advocates rational polypharmacy approach (oral and block) in difficult to treat painful conditions. Further controlled trials are warranted to further define the impact of such a combination therapy.

Cranial nerve vascular compression syndromes of the trigeminal, facial and vago-glossopharyngeal nerves: comparative anatomical study of the central myelin portion and transitional zone; correlations with incidences of corresponding hyperactive dysfunctional syndromes.

OBJECTIVE: The aim of this study was to evaluate the anatomy of the central myelin portion and the central myelin-peripheral myelin transitional zone of the trigeminal, facial, glossopharyngeal and vagus nerves from fresh cadavers. The aim was also to investigate the relationship between the length and volume of the central myelin portion of these nerves with the incidences of the corresponding cranial dysfunctional syndromes caused by their compression to provide some more insights for a better understanding of mechanisms. METHODS: The trigeminal, facial, glossopharyngeal and vagus nerves from six fresh cadavers were examined. The length of these nerves from the brainstem to the foramen that they exit were measured. Longitudinal sections were stained and photographed to make measurements. The diameters of the nerves where they exit/enter from/to brainstem, the diameters where the transitional zone begins, the distances to the most distal part of transitional zone from brainstem and depths of the transitional zones were measured. Most importantly, the volume of the central myelin portion of the nerves was calculated. Correlation between length and volume of the central myelin portion of these nerves and the incidences of the corresponding hyperactive dysfunctional syndromes as reported in the literature were studied. RESULTS: The distance of the most distal part of the transitional zone from the brainstem was 4.19 ± 0.81 mm for the trigeminal nerve, 2.86 ± 1.19 mm for the facial nerve, 1.51 ± 0.39 mm for the glossopharyngeal nerve, and 1.63 ± 1.15 mm for the vagus nerve. The volume of central myelin portion was 24.54 ± 9.82 mm(3) in trigeminal nerve; 4.43 ± 2.55 mm(3) in facial nerve; 1.55 ± 1.08 mm(3) in glossopharyngeal nerve; 2.56 ± 1.32 mm(3) in vagus nerve. Correlations (p < 0.001) have been found between the length or volume of central myelin portions of the trigeminal, facial, glossopharyngeal and vagus nerves and incidences of the corresponding diseases. CONCLUSION: At present it is rather well-established that primary trigeminal neuralgia, hemifacial spasm and vago-glossopharyngeal neuralgia have as one of the main causes a vascular compression. The strong correlations found between the lengths and volumes of the central myelin portions of the nerves and the incidences of the corresponding diseases is a plea for the role played by this anatomical region in the mechanism of these diseases.

[Neurosurgical treatment of vago-glossopharyngeal neuralgia]. / Traitement neurochirurgical de la névralgie vago-glossopharyngienne.

Glossopharyngeal neuralgia, more accurately called vago-glossopharyngeal neuralgia (VGPN) because of the frequent association with pain irradiation in the sensory territory of the vagus nerve, is not always recognized because its incidence is much lower than the incidence of trigeminal neuralgia (100 times more frequent). As in trigeminal neuralgia, when pain becomes resistant to anticonvulsants - its specific medical treatment - VGPN can almost always be cured by surgery. The first option is microvascular decompression, since vascular compression is the main cause of the neuralgia. Percutaneous thermorhizotomy at the foramen jugularis (pars nervosa) is only indicated as a second option, because of unavoidable sensorimotor deficits in the ninth and tenth nerves. Tractonucleotomies at the medullary level should be reserved essentially for pain of malignant origin.

[Improvement of diagnosis and treatment of glossopharyngeal neuralgia]. / Verbesserung der Diagnostik und Therapie der Glossopharyngeusneuralgie.

Differential diagnosis of neuralgias affecting the cranial nerves and of facial pain is often difficult. Glossopharyngeal neuralgia is much less common than trigeminal neuralgia and is not well known. Idiopathic neuralgia of the glossopharyngeal nerve sometimes occurs in association with neurovascular compression syndrome of the vagus and trigeminal nerves. High-resolution MRI of the brain stem with three-dimensional visualization allows a secure diagnosis of neurovascular compression and is useful in the planning of appropriate microsurgical decompression (Jannetta's operation).

A review of the epidemiology of painful diabetic peripheral neuropathy, postherpetic neuralgia, and less commonly studied neuropathic pain conditions.

Although the burden of neuropathic pain is well-recognized, the descriptive epidemiology of specific neuropathic pain conditions has not been well-described. While painful diabetic peripheral neuropathy and postherpetic neuralgia have been widely evaluated, many other peripheral and central neuropathic pain syndromes have been less frequently studied. This review summarizes incidence and/or prevalence information about two relatively frequent neuropathic pain conditions-painful diabetic peripheral neuropathy and postherpetic neuralgia-and similarly summarizes the more limited epidemiologic information available for other peripheral and central neuropathic pain conditions. The data suggest that while our knowledge is still incomplete, the high frequency of several of these conditions in specific populations should be considered an important impetus for further studies designed to evaluate their contribution to the overall burden of neuropathic pain.

Epidemiology of typical and atypical craniofacial neuralgias.

Trigeminal neuralgia (TN) has a prevalence of 0.1-0.2 per thousand and an incidence ranging from about 4-5/100,000/year up to 20/100,000/year after age 60. The female-to-male ratio is about 3:2. A review of several case series shows that pain is more predominant on the right side, but the difference is not statistically significant. TN is significantly associated with arterial hypertension, Charcot-Marie-Tooth neuropathy, glossopharyngeal neuralgia (GN) and multiple sclerosis. GN has an incidence of 0.7/100,000/year and epidemiological studies have shown it to be less severe than previously thought. Post-herpetic neuralgia has a comparable incidence to idiopathic TN. The epidemiology of the central causes of facial pain is still unclear, but it is known that persistent idiopathic facial pain is a widespread, not easily manageable problem.

[Glossopharyngeal neuralgia]. / Glossopharyngeusnevralgi.

BACKGROUND: Glossopharyngeal neuralgia is a rare but nevertheless important condition as it can be very incapacitating and as effective treatment is available. MATERIAL AND METHODS: We provide a review of the epidemiology, aetiology, differential diagnosis and treatment of this condition based on a Medline search. RESULTS AND INTERPRETATION: Glossopharyngeal neuralgia is characterised by severe unilateral pain in the posterior pharynx, tonsillar fossa, and base of the tongue. It is commonly provoked by swallowing, talking and coughing. In most cases the condition is caused by compression of the nerve by an artery, usually the postero inferior cerebellar artery. Medical treatment with carbamazepin or gabapentin is considered first choice. In patients not responding to medical treatment, surgery should be considered; microvascular decompression is considered the first choice of surgical treatment.