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* The International Collaboration on Cancer Reporting (ICCR) was established to internationally unify and standardize the pathologic reporting of cancers based on collected evidence, as well as to allow systematic multi-institutional intercountry data collection to guide cancer care in the future. Such collaborative efforts are particularly essential for developing an evidence base for rare neoplasms or those with marked geographic variation in incidence, such as the tumors of the ear and the temporal bone. The ear and the temporal bone, including the external auditory canal and the middle and inner ear, with the closely associated facial nerve, internal carotid artery, and internal jugular vein, is one of the most complex anatomic structures in the head and neck. A wide range of benign and malignant neoplasms arise in this region. The management of these neoplasms involves complex surgery because of the anatomic confines, and as such, both benign and malignant tumors are included in this data set, as the oncologically equivalent management requires a multidisciplinary approach and standardized nomenclature and terminology. Surgical procedures at this site result in multifaceted 3-dimensional specimens that can be difficult to handle at macroscopic exam. A comprehensive macroscopic examination is important for identifying critical prognostic factors and often requires clinical and radiologic correlation. Histologic examination is straightforward for basal cell or squamous cell carcinoma but can be quite challenging for other neoplasms. A summary of the ICCR guidelines for ear tumors is presented, along with discussion of the salient evidence and practical issues. doi: 10.5858/arpa.2018-0415-SA, The pathology report provides the fundamental information that informs patient care. (1) Thus, it is vital that the pathology report be accurate and include all of the essential prognostic and [...]

Purpose: This study examined the effects of age and gender on wideband energy absorbance in adults with normal middle ear function. Method: Forty young adults (14 men, 26 women, aged 20-38 years), 31 middle-aged adults (16 men, 15 women, aged 42-64 years), and 30 older adults (20 men, 10 women, aged 65-82 years) were assessed. Energy absorbance (EA) data were collected at 30 frequencies using a prototype commercial instrument developed by Interacoustics. Results: Results showed that the young adult group had significantly lower EA (between 400 and 560 Hz) than the middle-aged group. However, the middle-aged group showed significantly lower EA (between 2240 and 5040 Hz) than the young adult group. In addition, the older adult group had significantly lower EAthan the young adult group (between 2520 and 5040 Hz). No significant difference in EA was found at any frequency between middle-aged and older adults. Across age groups, gender differences were found with men having significantly higher EA values than women at lower frequencies, whereas women had significantly higher EA at higher frequencies. Conclusions: This study provides evidence of the influence of gender and age on EA in adults with normal outer and middle ear function. These findings support the importance of establishing age-and gender-specific EA norms for the adult population., With aging, changes may occur in the human auditory system, including the outer and middle ear. Changes in the outer and middle ear associated with aging have been documented in [...]

Auditory prostheses can partially restore speech comprehension when hearing fails. Sound coding with current prostheses is based on electrical stimulation of auditory neurons and has limited frequency resolution due to broad current spread within the cochlea. In contrast, optical stimulation can be spatially confined, which may improve frequency resolution. Here, we used animal models to characterize optogenetic stimulation, which is the optical stimulation of neurons genetically engineered to express the light-gated ion channel channelrhodopsin-2 (ChR2). Optogenetic stimulation of spiral ganglion neurons (SGNs) activated the auditory pathway, as demonstrated by recordings of single neuron and neuronal population responses. Furthermore, optogenetic stimulation of SGNs restored auditory activity in deaf mice. Approximation of the spatial spread of cochlear excitation by recording local field potentials (LFPs) in the inferior colliculus in response to suprathreshold optical, acoustic, and electrical stimuli indicated that optogenetic stimulation achieves better frequency resolution than monopolar electrical stimulation. Virus-mediated expression of a ChR2 variant with greater light sensitivity in SGNs reduced the amount of light required for responses and allowed neuronal spiking following stimulation up to 60 Hz. Our study demonstrates a strategy for optogenetic stimulation of the auditory pathway in rodents and lays the groundwork for future applications of cochlear optogenetics in auditory research and prosthetics., Introduction The electrical cochlear implant (CI) is considered the most successful neuroprosthesis. Implanted in more than 200,000 hearing-impaired subjects worldwide, CIs enable open speech comprehension in the majority of users [...]

The molecular basis of neurosensory development in the mouse ear is explored to provide a blueprint for possible enhancement of therapeutically useful transformation of stem cells into lost neurosensory cells. The use of stem cells combined with molecular insights into neurosensory cell specification and proliferation regulation of the ear might help in the neurosensory regeneration of mammalian ears.

Syka, Josef. Plastic Changes in the Central Auditory System After Hearing Loss, Restoration of Function, and During Learning. Physiol Rev 82: 601-636, 2002; 10.ll52/physrev.00002.2002.--Traditionally the auditory system was considered a [...]

In this paper, transient-evoked otoacoustic emissions (TEOAE's) are synthesized by an active auditory model, and decomposed by continuous wavelet transform (CWT) to study the frequency-latency relationship and the generation of TEOAE signals. The controlled voltage sources that relate to the mobile mechanism of the outer hair cells (OHC's) are proposed to serve as the generation sources of TEOAE signals. The state-variable method is adopted to calculate the auditory model. The mother wavelet used in CWT is selected on basis of the model. The results of this study show that the simulated TEOAE signal is similar to the clinically detected ones not only in the time-domain waveform, but also in the frequency-latency relationship. It seems to be clear that the generation of TEOAE signals is related to the same active mechanism as the cochlear sharp frequency selectivity. Index Terms - Auditory system, otoacoustic emissions, transient-evoked otoacoustic emissions (TEOAE's), wavelet transform.

An experiment was performed on guinea pigs to investigate the sympathetic vasoconstriction of identified small ear arteries in response to electrical stimulation of the cervical sympathetic nerve. The roles of the cotransmitters norepinephrine (NE), ATP and neuropeptide Y (NPY) in sympathetic vasoconstriction were also examined. Results showed that NE and NPY act as cotransmitters to regulate sympathetic constriction of small ear arteries, but ATP has not role in this constriction.

Mechanisms of hair cell tuning are discussed with focus on features intrinsic to the hair cells that are active in tuning and mechanosensitivity. Special emphasis is placed on mechanical tuning the the transduction apparatus. Evidence that mammals employ electrical tuning over any frequency range has not been found. The active electromechanical output of the hair bundle may have intrinsic frequency limitations.

The auditory system of the bat and its timing are discussed with information about echolocation. The lower brainstem has pathways that converge in the auditory midbrain where many neurons are tuned to biologically important aspects of sound. Interplay of the time-delayed excitatory/inhibitory inputs is important. The rate at which motor systems perform may be matched to the rate at which midbrain auditory neurons respond, and that corresponds to the cadence of sound, not fine structure.

The ability of sinusoidal yaw head rotation (YHR), which stimulates the horizontal semicircular canals without engaging the otolith organs, to alter both the muscle and skin sympathetic nerve activity (SNA) in humans was examined. Results showed that YHR was unable to produce any marked changes in sympathetic outflow to either muscle or skin indicating that the otolith organs but not the horizontal semicircular canals are involved in SNA regulation.

Little is known about the way membrane currents of the inner and outer hair cells (IHCs and OHCs) develop. Whole cell voltage clamp has been used to study time and voltage-dependent conductances of IHC, the cells that signal the reception of sound to the brain. Outward membrane currents of IHCs increase slowly before P11-P12, acquiring and additional fast component by P13. The results show that the developmental change in the expression of K- channels lead to the biophysical maturation of sensory cells within the mammalian ear.

The abilities to move ears and eyebrows were examined in 442 subjects (204 men, 238 women) categorized as right-handed (n=382) and left-handed (n=60, including mixed and ambidextrous-handed subjects). Approximately 22% could move one or the other ear and about 18% could move both ears simultaneously, but significantly more men could move both ears simultaneously. Significantly more men than women were able to move both the left and right eyebrow and the left ear. No differences were observed between right- and left-handers. Significant contingency correlations were observed between raising eyebrows and moving ears. Results are discussed with reference to a possible left ear-right hemisphere advantage for localising environmental sounds, primitive ear-moving abilities no longer functional in modern humans, and epiphenomenal by-products of other adaptive sex differences.

Same-sex female twins or female non-twins demonstrate nearly twice the average number of spontaneous otoacoustic emissions than females with male co-twins or opposite-sex dizygotic (OSDZ) females. The average in male twins or male non-twins in not very different from that in OSDZ females. This is because of a masculinizing effect on the auditory mechanisms of these OSDZ females, induced by prenatal exposure to high levels of androgens.

Auditory filter widths from the age of six to adulthood do not differ significantly when examined. A fixed single level and a fixed masker level procedures were used to measure the filter widths of different age-group from children of six years to adults and they showed no significant differences on the measures of Q10, ERB and K. The discrepancies may be seen when widely experimented, but these differences are, to a very large extent, negligible.

Amplification of sound inside the cochlea of the ear of an amphibian, which is affected by sensory and outer hair cells, determines the sensitivity of mammalian hearing. Displacements and feedback forces, which increase basilar membrane motion by reducing the inherent damping, are caused by these cells. Hair cells also exhibit membrane-potential-induced length changes-which indicates that the cells are capable of amplifying sound. The investigation is performed by using a displacement sensitive interferometer.

Author(s): David Holmes [illus. 4] How the ear works As sound waves enter the ear canal they make the eardrum vibrate. This vibration is transmitted by the ossicle bones -- [...]

Blocking a specific cell-signalling pathway in mice boosts the regeneration of ear tissue without any scarring after injury. Some amphibians and fish can regrow organs and appendages. To investigate the [...]

Abstract. In humans and animals alike, the localization of sound constitutes a fundamental processing task of the auditory system. Directioanl hearing relies on acoustic cues such as the interaural amplitude [...]

Cochlear outer hair cells (OHCs) are responsible for the exquisite sensitivity, dynamic range, and frequency-resolving capacity of the mammalian hearing organ. These unique cells respond to an electrical stimulus with a cycle-by-cycle change in cell length that is mediated by molecular motors in the cells' basolateral membrane. Recent work identified prestin, a protein with similarity to pendrin-related anion transporters, as the OHC motor molecule. Here we show that heterologously expressed prestin from rat OHCs (rprestin) exhibits reciprocal electromechanical properties as known for the OHC motor protein. Upon electrical stimulation in the microchamber configuration, rprestin generates mechanical force with constant amplitude and phase up to a stimulus frequency of at least 20 kHz. Mechanical stimulation of rprestin in excised outside-out patches shifts the voltage dependence of the nonlinear capacitance characterizing the electrical properties of the molecule. The results indicate that rprestin is a molecular motor that displays reciprocal electromechanical properties over the entire frequency range relevant for mammalian hearing.