Cochlear implantation has successfully restored the perception of hearing for nearly 200 thousand profoundly deaf adults and children. More recently, implant candidature has expanded to include those with considerable natural hearing which, when preserved, provides an improved hearing experience in noisy environments. But more than half of these patients lose this natural hearing soon after implantation. To reduce this burden, biosensing technologies are emerging that provide feedback on the quality of surgery. Here we report clinical findings on a new intra-operative measurement of electrical impedance (4-point impedance) which, when elevated, is associated with high rates of postoperative hearing loss and vestibular dysfunction. In vivo and in vitro data presented suggest that elevated 4-point impedance is likely due to the presence of blood within the cochlea rather than its geometry. Four-point impedance is a new marker for the detection of cochlear injury causing bleeding, that may be incorporated into intraoperative monitoring protocols during CI surgery. The preservation of cochlear structure and residual functional hearing has become the standard of care for cochlear implantation (CI). Hearing preservation is important to facilitate combined electrical and acoustic stimulation of the cochlea, as this improves speech recognition in noise and music appreciation 1-4. Cochlear structural preservation will ensure that the ear is ready for future, regenerative therapies 5,6. Structural and functional preservation of the cochlea depends not only upon the electrode design, but also the surgery. Electrodes must be introduced into the cochlea without causing injury. Until recently, technologies have not existed to guide the surgeon during the implant procedure; the operation has been conducted "blind" without the provision of feedback. Over recent years, we and others have begun to monitor cochlear function during cochlear implantation 7-10 , using the CI's own electrodes to monitor the electrophysiological response of the ear to acoustic stimulation. This technique, known as electrocochleography, has provided valuable information to guide surgeons during the operation; if the electrophysiological response is preserved during surgery, residual hearing is better after implantation 7-10. This paper is motivated by a desire to increase the scope of intraoperative monitoring during CI surgery. Current methods allow real-time detection of cochlear dysfunction, but these do not assess cochlear injury directly. Here we report on a method that has this potential. We have monitored "four-point" electrical impedance (4PI) from the implant's intracochlear electrodes during CI surgery. This impedance measurement is acquired by passing current between two outer electrodes whilst the voltage (from which the impedance may be inferred) is measured between two inner electrodes (Fig. 1A). The method is believed to assess the bulk impedance between the two inner electrodes, and has been used to differentiate between tissue and fluid ...

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This study aimed to evaluate the type, content, accessibility and quality of information available via the internet for patients with head and neck cancer. The Google search engine was used to generate lists of the first 100 websites for general head and neck cancer and the first ten for head and neck cancers by anatomical location (160 total). Websites were evaluated with the validated DISCERN and LIDA instruments, the SMOG (Simple measure of gobbledygook) readability score and against the JAMA (Journal of the American Medical Association) criteria. 40 of the 160 websites ranked by Google were suitable for analysis. Seven websites (17.5%) partially or fully achieved all four JAMA benchmarks and only one (2.5%) site achieved none. 28 (70%) included reference to quality of life factors. Correlations were identified between Google site rank and all four of our appraisal tools; LIDA (-0.966, p = 0.006), JAMA (-5.93, p = 0.028), DISCERN (-0.568, p = 0.037) and SMOG (4.678, p = 0.04). Google site rank and both government run sites (-35.38, p = 0.034) and sites run by universities or hospitals (-27.32, p = 0.016) also showed an association. Comparing our observations with those of Riordain in 2008, there has been little improvement in the quality of head and neck cancer information available online over this time. Given the variability in quality of information online, patients would benefit from being directed to reliable websites by clinicians.

This review discusses the various different lasers used in stapes surgery with regard to their properties and suitability for this type of surgery. In particular, the laser parameters used are discussed to facilitate their clinical use.

Air travellers are often not aware of prevention measures to avoid otic barotrauma, and the majority suffer as a result. Increasing public awareness of simple prevention measures would have a significant impact on air travellers.

Totally implantable cochlear implants may be able to address many of the problems cochlear implant users have around cosmetic appearances, discomfort, and restriction of activities. The major technological challenges that need to be solved to develop a totally implantable device relate to implanted microphone performance. Previous attempts at implanting microphones for cochlear implants have not performed as well as conventional cochlear implant microphones, and in addition have struggled with extraneous body or surface contact noise. Microphones can be implanted under the skin or act as sensors in the middle ear; however, evidence from middle ear implants suggest body and contact noise can be overcome by converting ossicular chain movements into digital signals. This article reviews implantable microphone systems and discusses the technology behind them.

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This chapter discusses the multifaceted future of cochlear implant design. Current research is focused on novel strategies relating to the electrode array, aiming to improve the neuronal health and spatial selectivity, and reduce the power consumption. Future design iterations will most likely improve the neuronal health by reducing insertion trauma, minimizing the inflammatory pathway that follows electrode insertion or through the use of neurotrophins or stem cells. Improvements in spatial selectivity and in speech recognition in difficult listening environments can be achieved through changes in the electrode/neural interface. Designing an array that brings the electrodes closer to neural tissue, or changing the method of stimulation with current steering or even optical or piezoelectric stimulation are discussed. Increasing the MRI compatibility is an important consideration, and devices allowing remote programming have a huge impact on worldwide provision. Technology exists to realize the elusive goal of a fully implantable cochlear implant, allowing continuous and invisible hearing. Ultimately, future technologies will be integrated to allow tailoring of implant design to the individual, thereby addressing the broad variability in user performance. At the same time, there is an urgent requirement for a high quality, low cost, mass-produced implant for the developing world.