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The present work examines the minimization of insertion forces of cochlear implant electrode carriers. Digital and physical models of the cochlea are created to measure the insertion forces. Factors such as the geometry of the cochlea models, insertion speed, and coating of the electrode carrier are investigated. The importance of insertion speed is also emphasized, and various studies on this topic are mentioned. Various coatings, both pharmacological and mechanically motivated, were examined. It is emphasized that studies on human preparations have limited significance and that investigations on artificial models can provide a better basis for comprehensive analyses. The present text passage describes the influence of insertion speed on insertion forces during cochlear implantation. Various laboratory samples were used, which were inserted at different speeds. It is found that an alginate coating on the electrode carrier significantly reduces insertion forces. The study provides experimental data that support the clinical requirement for slow insertions. The present text summary deals with the modeling and simulation of conical test bodies for compliant actuators in the electrode carrier. Various equations and formulas are used to analyze and verify scalability. A finite element simulation is also performed to numerically confirm scalability. The present text passage describes the results of investigations into the insertion depth of test bodies into cochlea models. It is found that individual adjustment of the test bodies can be achieved by varying the pressure. The importance of studies on cochlear morphology is highlighted. The present work examines various factors influencing insertion forces during the implantation of cochlear implant electrode carriers (CI-ET). The present study investigates various applications of balloon catheters for the dilation of vessels and tissues. Various studies are cited that deal with the dilation of vessels, heart valves, the Eustachian tube, coronary arteries, and vertebral bodies. The authors describe the pressure values used for dilation in the respective applications. The study provides important information on the application of balloon catheters in medical therapy. [Extracted from the article]

The present paper is a retrospective chart analysis of 115 patients treated after occupational accidents. They all suffered from hearing disorders, either after blunt head trauma (40%), acute noise trauma or after whiplash injury. Treatment consisted of medical and surgical measures so that the majority of the hearing disorders, e.g. sensorineural hearing loss (SNHL), combined HL and peripheral tinnitus, could be either completely restored or improved. A poor prognosis was correlated with central auditory changes, e.g. central tinnitus or hyperacusis. Moreover, a time interval of several months between the injury and the onset of treatment also worsened the overall prognosis. In our series, this was a rare exception and best outcome can be expected after starting treatment within the first 20 days after the trauma. [ABSTRACT FROM AUTHOR]

Objective: We wanted to statistically evaluate the results of a clinical examination of the presence of IgG-, IgM- and IgA-antibodies against herpes simplex virus (HSV) and varicella-zoster virus in the serum of patients with sudden sensorineural hearing loss (SSHL) and patients with vestibular neuronitis. Patients and Methods: Patients with SSHL (HSV: n = 150, VZV: n = 104) and vestibular neuronitis (HSV: n = 60, VZV: n = 45) who had been treated at the ENT department of the University Hospital of Jena from 1996 to 2000 were examined. Seroprevalences were determined by ELISA (Dade Behring Enzygnost® anti-HSV and anti-VZV). Anamnestic data and results of the clinical examinations of the seropositive patients were compared with those of seronegative patients and analysed statistically. Results: The vast majority (87.3%) of the patients with SSHL had elevated IgG titers against HSV, 9.3% were also positive for IgM. The prevalence of anti-VZV-IgG was calculated to be 98.1%; 4.8 were also VZV-IgM-positive while 24% had elevated IgA concentrations. Almost 3% (2.9%) were positive for IgM and IgA. Ninety percent of the patients with vestibular neuronitis were HSV-IgG positive, 3.3% of whom also had increased IgM levels. All patients with vestibular neuronitis (100%) had elevated VZV-IgG titers; 15.6% of them were also IgA positive, in 2 cases with simultaneous IgM elevation. The distribution of the age of patients with serologic signs of HSV or VZV reactivation had 2 peaks. Patients with SSHL and antibodies indicating a possible HSV reactivation suffered significantly more frequently from repeated hearing losses (36 versus 12%) and ear pain or pressure (21 versus 7%) than those without anti-HSV antibodies. Anti-VZV-IgA-positive patients with vestibular neuronitis experienced repeated vestibular dysfunctions (14 versus 5%), a complete loss of excitability in caloric vestibular testing (71 versus 45%) and headache (43 versus 8%) than anti-VZV-IgA-negative patients. Conclusions: Repeated hearing losses and ear pressure in patients with SSHL may be clinical signs of HSV reactivation. Headache and repeated vestibular dysfunction in patients with vestibular neuronitis may indicate a possible VZV reactivation. [ABSTRACT FROM AUTHOR]