[Orofacial pain - Trigeminal neuralgia and posttraumatic trigeminal neuropathy: Common features and differences]. / Orofazialer Schmerz - Trigeminusneuralgie und posttraumatische Trigeminusneuropathie : Gemeinsamkeiten und Unterschiede.

Neuropathic pain is the result of a lesion or disease of the somatosensory system in the peripheral or central nervous system. Classical trigeminal neuralgia and posttraumatic trigeminal neuropathy are pain disorders which oral and maxillofacial surgeons and dentists are confronted with in the differential diagnostics in routine daily practice. The etiopathogenesis of classical trigeminal neuralgia is attributable to pathological blood vessel-nerve contact in the trigeminal nerve root entry zone to the brain stem. The typical pain symptoms are characterized by sudden stabbing pain attacks. The pharmaceutical prophylaxis is based on the individually titrated administration of anticonvulsant drugs. The indications for interventional treatment are dependent on the course, response to drug treatment, resilience and wishes of the patient. The neuropathic mechanism of posttraumatic trigeminal neuropathy originates from nerve damage, which leads to peripheral and central sensitization with lowering of the pain threshold and multiple somatosensory disorders. The prophylaxis consists of avoidance of excessive acute and long-lasting pain stimuli. Against the background of the biopsychosocial pain model, the treatment of posttraumatic trigeminal neuropathy necessitates a multimodal, interdisciplinary concept.

Glossopharyngeal schwannomas: a 100 year review.

OBJECTIVES: To review the literature on glossopharyngeal schwannomas with a focus on clinical presentation, radiologic/audiologic characteristics, and management options, and to propose a mechanism explaining the nature of vestibulocochlear dysfunction seen with these tumors. STUDY DESIGN: Contemporary review. METHODS: English literature search for cases of primary isolated glossopharyngeal schwannomas and chart review of two new cases. RESULTS: A total of 42 glossopharyngeal schwannoma cases between 1908-2008 were reviewed. Of these 84% presented with vestibulocochlear symptoms whereas only 30% presented with glossopharyngeal symptoms. Tumors can occur anywhere along the CNIX; however, the majority of symptomatic cases are intracranial/intraosseous, which present with vestibulocochlear dysfunction. Reviewed cases typically described the caliber of CNVII and VIII on CT/MRI as normal. We present a case where notching and displacement of CNVIII by the tumor can be appreciated on MRI, allowing for the first correlation between clinical symptoms and imaging findings. Mid frequency SNHL was prevalent in contrast to the high-frequency pattern typical of vestibular schwannomas. Tonotopic studies of CNVIII mapped low-to-mid frequency fibers along the posterior medial surface corresponding to the area of greatest compression by glossopharyngeal schwannomas. CONCLUSION: Glossopharyngeal schwannomas usually present with vestibulocochlear rather than glossopharyngeal symptoms, likely due to CNVIII compression and displacement by tumor, which can be better appreciated with modern imaging. The tumor's location posterior and medial to CNVIII combined with the complex CNVIII tonotopic organization may account for the preferential mid-frequency hearing loss seen in these patients.