Eur Arch Otorhinolaryngol
December 2010
Idiopathic sudden sensorineural hearing loss (ISSNHL) is a heterogenic disease. Multiple factors influencing aetiology and prognosis are discussed. A retrospective clinical characterisation and analysis of family history of ISSNHL patients was performed to investigate influences on the disease.
View Article and Find Full Text PDFThe present study was performed to elucidate the hearing development in the progressive motor neuronopathy (pmn) mouse mutant. This mouse has been used as a model for human motoneuron disease. A missense mutation in the tubulin-specific chaperon E (Tbce) gene on mouse chromosome 13 was localized as the underlying genetic defect.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
September 2009
Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a growth factor of the transforming growth factor-beta superfamily. Members of this protein family are involved in the development of various mammalian tissues, including the inner ear. As their notations indicate, they also have well-known effects on bone formation and regeneration.
View Article and Find Full Text PDFBackground: With the increasing use of cochlear implants (CIs), the insertion of alloplastic material into the inner ear is nowadays an established treatment for severe to profound hearing loss in children and adults. Beyond its widespread use, the biocompatibility of the CI electrode and its interaction with the neural structures of the cochlea is not yet established.
Methods: To investigate the survival and growth behavior of spiral ganglion neurons on different CI materials, spiral ganglion explants from newborn rats were cultured on silicone and platinum, on a surface combination of silicone and platinum, and, finally, on a CI electrode.
Objective: This case is reported in order to demonstrate the importance of detailed clinical analysis, including evaluation of personal and family history, in the differential diagnosis of sudden sensorineural hearing loss.
Case Report: A 50-year-old woman presented with a sudden onset of sensorineural hearing loss in her right ear. She had experienced three previous episodes of sudden sensorineural hearing loss in her left ear, at the ages of 35, 48 and 50 years.
To explore the role of nerve growth factor receptor p75(NTR) during the terminal neuronal development of the mammalian cochlea the onset of hearing and the in vitro response of spiral ganglion neurites to neurotrophin 3 (NT-3), which is known to play a critical role during neonatal inner ear development, were investigated in p75(NTR)-deficient mice (p75(NTR)-/-). Auditory-evoked brain stem response recordings from p75(NTR)-/- and wild-type (WT) littermates were measured from postnatal days (PD) 8 to 23. Additionally, spiral ganglion explants from p75(NTR)-/- and WT animals were dissected and cultured in an organotypic tissue culture system.
View Article and Find Full Text PDFBackground: This study was designed to assess the postoperative quality of life (QoL) of 30 patients successfully treated with a laryngectomy.
Methods: QoL was evaluated with two validated questionnaires (EORTC-QLQ-C30 and EORTC-QLQ-H&N35) during the regular outpatient follow-up. To analyse the long-term quality of life, we divided our collective into two groups of patients; one consisting of patients whose treatment had been completed less than five years ago and one whose therapy had been finished more than five years ago.
Skin diseases on the external aspect of the ear are seen in a variety of medical disciplines. Dermatologists, othorhinolaryngologists, general practitioners, general and plastic surgeons are regularly consulted regarding cutaneous lesions on the ear. This article will focus on those diseases wherefore surgery or laser therapy is considered as a possible treatment option or which are potentially subject to surgical evaluation.
View Article and Find Full Text PDFBackground: The etiology and factors influencing the prognosis of idiopathic sensorineural hearing loss are still in focus. To determine pathogenetic relevant factors, a detailed clinical characterization of patients with idiopathic sudden sensorineural hearing loss remains to be performed.
Methods: The history of 103 patients who presented with a sudden sensorineural hearing loss and received a standard treatment with prednisolone und pentoxyphylline (Stennert-Schema) has been investigated with a new questionnaire.
Objectives: We evaluated long-term quality of life of patients successfully treated with either laser-assisted microsurgery alone or combined with adjuvant radiotherapy for laryngeal carcinoma.
Patients And Methods: The study included 53 patients who were treated by laser surgery and 16 patients who were treated by laser surgery combined with adjuvant radiotherapy. Quality of life was evaluated with two validated questionnaires: the global EORTC QLQ-C30 and the head and neck specific EORTC QLQ-H&N35.
Background: Utilising the enormous proliferation and multi-lineage differentiation potentials of somatic stem cells represents a possible therapeutical strategy for diseases of non-regenerative tissues like the inner ear. In the current study, the possibility of murine neural stem cells to contribute to the developing inner ear following blastocyst injection was investigated.
Methods: Fetal brain-derived neural stem cells from the embryonic day 14 cortex of male mice were isolated and expanded for four weeks in neurobasal media supplemented with bFGF and EGF.
Vasodilator-stimulated phosphoprotein (VASP) has been found to be involved in intracellular signalling pathways and to play an important role in the actin associated organization and formation of the cytoskeleton. Since differential VASP expression was noted in inner ear tissues, the present study was performed to investigate the hearing development in VASP deficient mice. Hearing development in VASP-/- mice and wild type animals was investigated by auditory brain stem (ABR) measurements.
View Article and Find Full Text PDFObjective/hypothesis: Implantable hearing devices such as cochlear implants and auditory brainstem implants deliver auditory information through electrical stimulation of auditory neurons. The combination of microelectronic electrodes with auditory nerve cells may lead to further improvement of the hearing quality with these devices. Whereas several kinds of neurons are known to grow on semiconductor substrates, interactions of cochlear nucleus (CN) neurons with such materials have yet to be described.
View Article and Find Full Text PDFLaryngorhinootologie
December 2006
Background: Commonly used staging procedures often cannot predict the absence of lymphatic micro- metastases in squamous cell carcinoma (SCC) of the head and neck. Therefore in many cases an elective neck dissection (ND) is necessary. In the surgical therapy of melanoma or breast cancer the presence of metastases can be evaluated securely by identification and examination of the sentinel lymph node (SLN).
View Article and Find Full Text PDFObjectives: To investigate posterior external ear canal wall reconstruction with a composite cartilage titanium mesh graft in canal wall down tympanoplasty and revision surgery for open mastoids.
Study Design: Retrospective case review.
Setting: Tertiary referral centre.
The study was performed to identify the incidence and histology of rare tumors with growth restricted to the internal auditory canal (IAC) that are different from vestibular schwannoma (VS). Furthermore, the question was addressed whether a preoperative diagnosis would be possible in these cases. A series of 351 patients that were operated on for IAC tumors through a transtemporal or translabyrinthine approach was investigated retrospectively.
View Article and Find Full Text PDFStudies have demonstrated different pathogenetic key factors in gentamicin-induced hair cell death. The production of reactive oxygen species (ROS), as well as apoptosis-related genes, play a critical role. However, a coordinated large-scale investigation of gene expression in the organ of Corti (OC) exposed to gentamicin has not yet been conducted.
View Article and Find Full Text PDFAt birth, one in 850 babies are profoundly deaf, and hearing loss affects more than 50% of all people over 60 years of age. While hearing loss caused by disease of the external and/or middle ear is treatable, hearing loss as a result of damage to and loss of hair cells and/or auditory neurons can only be alleviated using prosthetic devices such as hearings aids or cochlear implants.
View Article and Find Full Text PDFBackground: Rhinogenous brain abscesses usually originate from a frontal sinusitis, rarely from the ethmoidal system or the maxillary sinus. However, there are different pathways that can lead to the transfer of a maxillary infection to the endocranial compartment.
Patient: A patient with frontal brain abscesses originating from a maxillary sinus infection is presented and diagnostic steps, therapy as well as pathophysiology are discussed.
To identify possible intracellular mediators of hair cell (HC) death due to ototoxins, we treated basal-turn, neonatal, rat HCs in vitro with several intracellular signaling inhibitors, prior to and during gentamicin exposure. The general guanine nucleotide-binding protein (G-protein) inhibitor, GDP-betaS (1 mM), provided potent HC protection, suggesting involvement of G-proteins in the intracellular pathway linking gentamicin exposure to HC death. ADP-betaS had minimal effect, indicating that the protection is specific to guanosine diphosphate (GDP)-binding, rather than a general reaction to nucleotides.
View Article and Find Full Text PDFThe use of stem cells offers new and powerful strategies for future tissue development and engineering. Common features of stem cells are both their capacity for self-renewal and the ability to differentiate into mature effector cells. Since the establishment of embryonic stem cells from early human embryos, research on and clinical application of human ES cells belong to the most controversial topics in our society.
View Article and Find Full Text PDFBackground: During the last few years, several laser systems have been applied for procedures in middle ear surgery. In this study, we determined the technical parameters for the dissection of the middle ear ossicles with the CO(2) laser and analyzed the histological findings.
Methods: The malleus necks of 16 human temporal bones were dissected under standardized conditions using a CO(2) laser with a power output between 35 and 55 kW/cm(2).
We have previously demonstrated by FACS analysis and histochemistry that Fas ligand (FasL) increases on cochlear cell surfaces after immune response or stimulation with gamma-interferon (IFN-gamma). To determine whether the appearance of FasL on cochlear cell membranes is related to gene expression or to posttranslational events, cochlear cells were treated with IFN-gamma. They were evaluated for FasL gene expression by real-time PCR and for FasL protein localization by confocal microscopy of permeabilized and immunolabeled cells.
View Article and Find Full Text PDFObjectives/hypothesis: During the terminal innervation of the developing organ of Corti, fibroblast growth factor-1 (FGF-1) messenger RNA has been shown to be transiently expressed in the sensory epithelium of the rat, suggesting that this growth factor may contribute to developmental processes such as innervation and synaptogenesis of the inner and outer hair cells. In a previous study it has been demonstrated that exogenous FGF-1 supports rat spiral ganglion neurite extension in vitro, whereas a secreted form of FGF-1 produced by transfected fibrocytes induces neurite branching and targeting.
Study Design: Response of spiral ganglion neurites to FGF-1-coupled beads was compared with the response to noncoupled control beads.