Evidence-based diagnostic use of VEMPs : From neurophysiological principles to clinical application.

BACKGROUND: Vestibular evoked myogenic potentials (VEMPs) are increasingly being used for testing otolith organ function. OBJECTIVE: This article provides an overview of the anatomical, biomechanical and neurophysiological principles underlying the evidence-based clinical application of ocular and cervical VEMPs (oVEMPs and cVEMPs). MATERIAL AND METHODS: Systematic literature search in PubMed until April 2019. RESULTS: Sound and vibration at a frequency of 500 Hz represent selective vestibular stimuli for the otolith organs. The predominant specificity of oVEMPs for contralateral utricular function and of cVEMPs for ipsilateral saccular function is defined by the different central projections of utricular and saccular afferents. VEMPs are particularly useful in the diagnosis of superior canal dehiscence and otolith organ specific vestibular dysfunction and as an alternative diagnostic approach in situations when video oculography is not possible or useful. CONCLUSION: The use of VEMPs is a simple, safe, reliable and selective test of dynamic function of otolith organs.

[Evidence-based diagnostic use of VEMPs : From neurophysiological principles to clinical application. German version]. / Evidenzbasierte VEMP-Diagnostik : Von den neurophysiologischen Grundlagen zur klinischen Anwendung.

BACKGROUND: Vestibular evoked myogenic potentials (VEMPs) are increasingly being used for testing otolith organ function. OBJECTIVE: This article provides an overview of the anatomical, biomechanical and neurophysiological principles of an evidence-based clinical application of ocular and cervical VEMPs (oVEMPs and cVEMPs). MATERIAL AND METHODS: Systematic literature search in PubMed until April 2019. RESULTS: Sound and vibration at a frequency of 500 Hz represent selective vestibular stimuli for the otolith organs. The predominant specificity of oVEMPs for contralateral utricular function and of cVEMPs for ipsilateral saccular function is defined by the different neuronal projections of the utricle and the saccule. VEMPs are particularly useful in the diagnosis of superior canal dehiscence and otolith organ-specific vestibular dysfunction and as an alternative diagnostic approach in situations when video oculography is not possible or useful. CONCLUSION: The use of VEMPs is a simple, safe, reliable and selective test of dynamic function of otolith organs.

[Neuro-otology: at the borders of ear and brain]. / Neurootologie: Grenzfälle zwischen Ohr und Gehirn.

Vertigo and dizziness are frequent chief complaints in clinical practice. Symptoms may originate from otological, neurological, medical and psychiatric etiologies, which poses an interdisciplinary challenge. Systematic analysis of case history and clinical examination generally allow classification into peripheral-, central- or non-vestibular disorders. The most important criteria for differentiation are the timeline, quality of symptoms, modulating factors and accompanying symptoms. As concerns the clinical examination, the following tests are relevant: head impulse test, test for spontaneous nystagmus, positional nystagmus, central ocular motor signs and the Romberg test. However, neuro-otological disorders with combined peripheral and central vestibular pathology do exist. Occlusion of the anterior inferior cerebellar artery results in ischemia of the labyrinth and cerebellum and therefore causes acute vestibular syndrome and unilateral hearing loss. Repetitive attacks of vertigo or dizziness which are accompanied by ear symptoms and headaches may be due to an overlap syndrome of Menière's disease and vestibular migraine. In this case patients often have to be treated with a dual prophylactic medication to control symptoms. In case of chronic dizziness and instability of gait a subsample of patients may suffer from CANVAS, which is a combination of bilateral vestibulopathy, a cerebellar syndrome and polyneuropathy. Chronic dizziness with signs of peripheral and central vestibular dysfunction can also originate from tumors of the cerebellopontine angle with compression of central structures. In conclusion, the diagnostic algorithm in the workup of patients with vertigo and dizziness should always include tests for peripheral and central vestibular and ocular motor function.

[Complications and pitfalls in surgery of the ear/lateral skull base]. / Fehler und Gefahren: Ohrchirurgie und Chirurgie der lateralen Schädelbasis.

Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills.Following a summary about general aspects in pre-, intra- and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation, surgery of vestibular schwannomas, and jugulotympanal paragangliomas. Based on these exemplary procedures, basic "do's and don'ts" of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed.An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process.

[Liposarcoma: a rare differential diagnosis of cervical space occupation]. / Liposarkom: Seltene Differenzialdiagnose der zervikalen Raumforderung.

With less than 100 cases described in the literature, the incidence of liposarcoma in the head and neck is very low. We report on a 54-year-old patient with a liposarcoma of the right cervical soft tissue. After complete tumor extirpation the patient underwent radiotherapy. Diagnostics, histopathological classification, therapy and prognosis of liposarcoma are discussed in this case report and review of the literature.