In-vitro and in-vivo measurement of the animal's middle ear acoustical response by partially implantable fiber-optic sensing system.

The main obstacle in realization of a totally implantable hearing aid is a lack of reliable implantable microphone. In this paper we have described a potentially miniature fiber-optic vibrometer based on a modified Michelson interferometer, designed to serve as a middle-ear microphone for totally implantable cochlear- or middle-ear hearing aids. A model of the sensing system was used for in-vitro and in-vivo investigation of acoustical response of sheep's middle-ear ossicles.

Effects of intraoperatively applied glucocorticoid hydrogels on residual hearing and foreign body reaction in a guinea pig model of cochlear implantation.

Conclusion: The intraoperative application of glucocorticoid-loaded hydrogels seems to cause a reduction in neutrophil infiltration. No beneficial effect on hearing thresholds was detected.

Objectives: To evaluate the application of dexamethasone- and triamcinolone acetonide-loaded hydrogels for effects on hearing preservation and foreign body reaction in a guinea pig model for cochlear implantation (CI).

Correlative 3D-imaging of Pipistrellus penis micromorphology: Validating quantitative microCT images with undecalcified serial ground section histomorphology.

Detailed knowledge of histomorphology is a prerequisite for the understanding of function, variation, and development. In bats, as in other mammals, penis and baculum morphology are important in species discrimination and phylogenetic studies. In this study, nondestructive 3D-microtomographic (microCT, µCT) images of bacula and iodine-stained penes of Pipistrellus pipistrellus were correlated with light microscopic images from undecalcified surface-stained ground sections of three of these penes of P.

Radiological assessment of the inferior alveolar artery course in human corpse mandibles.

Objectives: CT assessment of the entire course of the inferior alveolar artery (IAA) within the mandibular canal.

Methods: After contrast medium injection (180 or 400 mg/ml iodine concentration) into the external carotid arteries of 15 fresh human cadaver heads, the main IAA's position in the canal (cranial, buccal, lingual or caudal) was assessed in dental CT images of partially edentulous mandibles.

Results: The course of the main IAA could be followed at both iodine concentrations.

The role of materials biocompatibility for functional electrical stimulation applications.

The biocompatibility of all metallic, polymeric, or ceramic materials used for functional electrical stimulation is governed by the inevitable inflammatory tissue response, but possibly also by immunological reactions to the bulk material or released constituents. Besides chemical, physical, and corrosion properties of the conductive electrode materials, increased surface area and roughness of the electrode can influence tissue contact and signal delivery, and can also affect electrode-tissue impedance due to increased connective tissue encapsulation. The polymeric materials used for electrode insulation and those for leads and stimulator packaging seem more or less compatible in an aggressive biological environment.