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Vestibular diagnostics and therapy is the mirror of technological, scientific and socio-economics trends as are other fields of clinical medicine. These trends have led to a substantial diversification of the field of neurotology. The improvements in diagnostics have been characterized by the introduction of new receptor testing tools (e. g., VEMPs), progress in imaging (e. g., the endolymphatic hydrops) and in the description of central-vestibular neuroplasticity. The etiopathology of vestibular disorders has been updated by geneticists (e. g., the description of the COCH gene mutations), the detection of structural abnormalities (e. g., dehiscence syndromes) and related disorders (e. g. migraine-associated vertigo). The therapeutic options were extended by re-evaluation of techniques known a long time ago (e. g., saccus exposure), the development of new approaches (e. g., dehiscence repair) and the introduction of new drug therapy concepts (e. g., local drug delivery). Implantable, neuroprosthetic solutions have not yet reached experimental safety and validity and are still far away. However, externally worn neuroprosthetic solution were introduced in the rehab of vestibular disorders (e. g., VertiGuard system). These and related trends point into a medical future which is characterized by presbyvertigo as classical sign of the demographic changes ahead, by shortage of financial resources and a medico-legally over-regulated, even hostile environment for physicians in clinical medicine., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Both LAV- (large or enlarged vestibular aqueduct) and Pendred-syndrome are autosomal recessive diseases. In contrast to Pendred-syndrome, LAV-syndrome is characterised only by an enlarged vestibular aqueduct. Pendred-syndrome is a more complex disease. Classically it is characterised by sensorineural hearing loss and enlargement of the thyroid gland. Up to now, only mutations in SLC26A4 gene are known as being responsible for both syndromes. The gene for Pendred-syndrome (SLC26A4) has been localised by linkage analysis of chromosome 7q31. This protein is expressed in the inner ear, thyroid gland, kidney, and placenta. Functional analysis of the gene product (pendrin) in Xenopus laevis oocytes revealed that pendrin acts as an iodide/chloride and chloride/formate exchanger., Method: Each of the exons and flanking splice regions of the SLC26A4 gene were analysed by direct sequencing. Haplotype analysis was undertaken with microsatellite markers spanning a 5 Mbp area around the localisation of the SLC26A4 gene., Results: In sequence analysis of 42 patients with bilateral enlargement of the vestibular aqueduct, no mutation could be identified in 30 % of cases. In some of these cases, a linkage to the gene localisation on chromosome 7q31 could not be detected., Conclusion: Our results indicate evidence for a second gene involved in the development of LAV-syndrome.