High Frequency Sounds Research Articles

The evolution and progress of intraoperative monitoring of the external branch of the superior laryngeal nerve in thyroid surgery

Hypoparathyroidism and recurrent laryngeal nerve (RLN) damage are the most frequent reported morbidity in thyroid surgery whereas damage of the external branch of the superior laryngeal nerve (EBSLN) has been considered to be the most neglected sequel. EBSLN injury results in subtle changes in voice as a result of dysfunction of the cricothyroid muscle (CTM): changed basic voice frequency, deterioration of voice quality in the production of high frequency sounds and reduced voice projection. Symptoms of this dysfunction are usually more notable for professional voice users and can be difficult to diagnose. EBSLN injury can happen during dissection of the vessels of the upper thyroid pole due to proximity between the nerve and these vessels. Several maneuvers can minimize the risk of injury to the EBSLN including visual identification of the nerve before ligation of the upper thyroid pole vessels and use of either a nerve stimulator or intraoperative neuromonitoring (IONM) for neuromapping and evidence of the EBSLN identification. The EBSLN monitoring is relied on evaluation of CTM twitch (present in all patients) and electromyographic curve traced by the monitor using surface tube electrodes within the vocal folds which present in the majority but not all individuals (70–80% of patients using standard EMG tubes) or approaching to 100% of patients (using NIM TriVantage tubes). IONM has a potential to increase the rate of the EBSLNs identification, diminish prevalence of neural damage, and decrease prevalence of postoperative voice impairment which has been repeatedly supported by recently published data. It is advised that at the end of upper thyroid lobe dissection the EBSLN should be stimulated at the most cranial arc of dissection to confirm not only anatomical but what is even more important functional preservation of intact neural function.

Follicle Detection in Digital Ultrasound Images using Bi-Dimensional Empirical Mode Decomposition and Mathematical Morphology

Ultrasound Imaging is one of the technique used to study inside human body with images generated using high frequency sounds waves. The applications of ultrasound images include examination of human body parts such as Kidney, Liver, Heart and Ovaries. This paper mainly concentrates on ultrasound images of ovaries. The detection of follicles in ultrasound images of ovaries is concerned with the follicle monitoring during the diagnostic process of infertility treatment of patients.Monitoring of follicle is important in human reproduction. This paper presents a method for follicle detection in ultrasound images using Bidimensional Empirical Mode Decomposition and Mathematical morphology. The proposed algorithm is tested on sample ultrasound images of ovaries for identification of follicles and classifies the ovary into three categories, normal ovary, cystic ovary and polycystic ovary. The experiment results are compared qualitatively with inferences drawn by medical expert manually and this data can be used to classify the ovary images.

Long-term characterization of the marine soundscape in Kona, Hawaii

Soundscape analysis of marine environments is still a new field of inquiry, with the majority of studies focusing on individual species or acoustic functional groups. Additionally, the challenges of making long term acoustic recordings in marine habitats, particularly in deep water, have limited the duration of many analyses. The Pacific Islands Fishery Science Center has been collecting passive acoustic data at a depth of 630 m off the Kona coast of the Island of Hawaii since 2007, and has recently begun a soundscape analysis effort to characterize the contributors to the local acoustic environment. This project seeks to examine not only low frequency noise patterns, below 1 kHz, but also higher frequency sounds that may overlap in frequency with the signals of many cetacean species. We have begun by identifying the relative contribution of odontocete echolocation, and also close approaches of boats and the presence of echosounders. The temporal patterns in these signals reveal daily and seasonal cycles in biological and anthropogenic sounds, which provide both detailed insight into the interactions between humans, animals and their environment, and long term trends in activity of those sound sources.Soundscape analysis of marine environments is still a new field of inquiry, with the majority of studies focusing on individual species or acoustic functional groups. Additionally, the challenges of making long term acoustic recordings in marine habitats, particularly in deep water, have limited the duration of many analyses. The Pacific Islands Fishery Science Center has been collecting passive acoustic data at a depth of 630 m off the Kona coast of the Island of Hawaii since 2007, and has recently begun a soundscape analysis effort to characterize the contributors to the local acoustic environment. This project seeks to examine not only low frequency noise patterns, below 1 kHz, but also higher frequency sounds that may overlap in frequency with the signals of many cetacean species. We have begun by identifying the relative contribution of odontocete echolocation, and also close approaches of boats and the presence of echosounders. The temporal patterns in these signals reveal daily and seasonal cycles ...

Presidency on elderly people with arterial hypertension and mellitus diabetes: literature review

Introduction: Population aging is now a global event, determining greater growth of the elderly population in relation to the other age groups. The hearing loss due to aging is known as presbycusis, characterized by bilaterally decreased auditory acuity, generally for high frequency sounds, due to degenerative and physiological changes in the auditory system that have arisen with increasing age. Studies have shown that chronic diseases affecting the elderly may be related to hearing disorders. Among these diseases, the most frequent are diabetes mellitus and hypertension. Objective To describe the hearing loss of elderly patients with diabetes mellitus (DM) and systemic arterial hypertension (SAH) from a bibliographic survey. Methodology: This is a bibliographic review research carried out in the SciELO database. Inclusion criteria were: complete scientific papers published in the Portuguese language, published in the period from 2011 to 2015,that present in the title some of the descriptors: elderly, diabetes mellitus, systemic arterial hypertension. Results and Discussion: We found 27 articles, of which 7 were selected for the review, since the others did not present data relevant to the research, were duplicated and did not fit the other inclusion criteria. According to the research, drastic changes were observed when comparing the elderly living with DM and SAH with those without chronic diseases, also showing an adverse effect on the cochlea, resulting in the loss of hair cells that, through mechanotransition, detect the sounds. Conclusion: It can be observed that the elderly with DM and SAH presented higher hearing loss of high frequency neurosensory when compared to groups without these chronic diseases, suggesting a synergistic effect of the medications to treat the pathologies.

Age-dependent gene expression in the inner ear of big brown bats (Eptesicus fuscus).

For echolocating bats, hearing is essential for survival. Specializations for detecting and processing high frequency sounds are apparent throughout their auditory systems. Recent studies on echolocating mammals have reported evidence of parallel evolution in some hearing-related genes in which distantly related groups of echolocating animals (bats and toothed whales), cluster together in gene trees due to apparent amino acid convergence. However, molecular adaptations can occur not only in coding sequences, but also in the regulation of gene expression. The aim of this study was to examine the expression of hearing-related genes in the inner ear of developing big brown bats, Eptesicus fuscus, during the period in which echolocation vocalizations increase dramatically in frequency. We found that seven genes were significantly upregulated in juveniles relative to adults, and that the expression of four genes through development correlated with estimated age. Compared to available data for mice, it appears that expression of some hearing genes is extended in juvenile bats. These results are consistent with a prolonged growth period required to develop larger cochlea relative to body size, a later maturation of high frequency hearing, and a greater dependence on high frequency hearing in echolocating bats.

Changes in the content of fatty acids in CA1 and CA3 areas of the hippocampus of Krushinsky–Molodkina rats after single and fivefold audiogenic seizures

Audiogenic seizures (AS) are generalized seizures evoked by high frequency sounds. Since the hippocampus is involved in the generation and maintenance of seizures, the effect of AS on the composition and content of fatty acids in the CA1 and CA3 hippocampal areas of AS-susceptible Krushinsky-Molodkina (KM) rats on days 1, 3, and 14 after single and fivefold seizures were examined. The total content of all fatty acids in field СА1 was found to be lower compared with the control at all times of observation after both a single seizure or fivefold seizures. The total content of fatty acids in field СА3 decreased at all times of examination after a single seizure, whereas it remained unchanged on days 3 and 14 following five AS. The content of omega-3 fatty acids in both fields at all times of observation after a single seizure and fivefold AS did not significantly differ from that in intact animals. The absence of significant changes in the content of stearic and α-linolenic acids and a considerable decrease in the levels of palmitic, oleic, and eicosapentaenoic acids were common to both fields at all times after both a single seizure or fivefold AS.The changes in the content of fatty acids in the СА3 and СА1 fields of the brain of AS-susceptible rats indicate that fatty acids are involved in both the development of seizure activity and neuroprotective anticonvulsive processes.

Back to the Beach: Adaptations that Enabled Terrestrial Mammals to Return to the Water

Modern aquatic mammals are extremely diverse. This includes classic marine mammals such as cetaceans (whales, including dolphins and porpoises) and sirenians (manatees, dugongs), but also many amphibious mammals that spend some time on land (e.g., seals, otters, hippos, polar bears). Aquatic mammals retain terrestrial‐based systems that have been vastly modified for existence in water, but this alone does not make them extreme. However, within this group are some notable extremists: the cetaceans. They have the strangest anatomical aquatic adaptations – the ones with the “‐est” adjectives – enabling the deepest dive, slowest pulse, longest apnea, shortest exhalation, largest nose, narrowest mandible, strongest suction, biggest hyoid, widest mouth, stretchiest gular region, hairiest moustache, loudest sound, lowest song, longest tooth, highest vocalization, fattiest ear, tiniest external auditory meatus, densest tympanic bulla, curliest tongue, smoothest skin, stiffest cervical vertebrae, bumpiest forelimb, heaviest testes, and fastest copulation. For example, the sperm whale can dive to the bottom of the ocean and hold its breath for nearly an hour. Its head that is nearly one‐third of its body length, and is comprised of an enormous nose modified for sound production. Its mandible may plow the sea floor, and the hyoid and tongue create suction to engulf prey. The blue whale is the biggest mammal that ever existed, and has the widest mouth for engulfing prey. It has the largest larynx capable of making the loudest and lowest vocalizations. The narwhal has an elongated tooth that is likely the basis for the legend of the unicorn's horn. The dolphin uses modified nostrils to generate ultra high frequency sounds for echolocation, and uses acoustic fats as pinnae to receive sounds. A whale calf can curl the tongue into a straw for channeling milk when nursing underwater. Whale skin is very smooth enabling hydrodynamic water flow, and compressed/fused cervical vertebrae eliminate friction from lateral head deviations. The elongated flippers of humpback whales have bumps on the leading edge that increase efficiency. The porpoise is the smallest whale but has the largest testes and longest penis that can be rapidly extruded for the quickest mating. These amazing anatomical aquatic adaptations make cetaceans one of the most extreme groups of animals on Earth.

Creating ethical brands: the role of brand name on consumer perceived ethicality

A critical component of brand equity is consumer perceived ethicality (CPE) of the brand. Yet, little is known about how to create positive brand CPE. We offer that the starting point for creating brand CPE is with the brand-naming decision. Drawing on sound symbolism theory, we propose that certain brand name characteristics better convey ethicality. Two studies are conducted. Study 1 finds that higher frequency sounds in brand names better convey ethicality than lower frequency sounds. Study 2 finds that brand names can positively impact brand CPE in the presence of additional information, in particular, information that reflects negatively on the brand’s ethical behavior. These results suggest that marketers be more involved at the onset of creating an ethical brand image.

Meteorological effects on the noise reducing performance of a low parallel wall structure

Numerical calculations, scale model experiments and real-life implementations have shown that the insertion of a closely spaced array of low parallel walls of finite dimension beside a road is potentially useful for road traffic noise abatement. However, previous studies did not consider atmospheric effects. In this work, numerical techniques have been used to predict the sound reduction provided by a low parallel wall structure, subject to wind and temperature related atmospheric effects. Three full-wave prediction schemes show very good agreement when looking at the insertion loss of a low 6m wide parallel wall structure, consisting of 24 regularly spaced 0.2-m high rigid walls. Meteorological effects are predicted not to deteriorate the insertion loss (relative to rigid flat ground) of the parallel wall array in the low frequency range. However, at high sound frequencies the insertion loss is strongly reduced by downward refraction at a distance of 50m in case of strong wind. Consequently, overall A-weighted road traffic noise insertion loss will be significantly lower during wind episodes. Although weak turbulence does not alter the energy time-averaged insertion losses, strong turbulence reduces the noise shielding in the high frequency range also. As with conventional noise walls, when considering use of low parallel wall structures for noise reduction outdoors, even at short distances, atmospheric effects should be considered.

The Foundations of High-Frequency Hearing in Early Mammals

It has become common in the paleontological literature to assume that the presence of secondary bony laminae in the cochleae of early mammals indicates that these species were able to perceive high sound frequencies (>20 kHz). This review examines the validity of this idea in the context of comparative physiological data from extant amniotes and surveys a number of unique features of mammalian cochleae that correlate with high-frequency hearing. As it is difficult to imagine how all of these features could have arisen simultaneously, high-frequency hearing probably had a more gradual origin. This suggests that the presence or absence of secondary laminae should be interpreted with greater caution.

Hearing Loss and Associated Factors in Iranian Patients with Type 2 Diabetes: A Case-Control Study

Background: Hearing loss is an important impairment that occurs in the diabetics and affects their quality of life. There is still a paucity of studies on the relationship between diabetes and hearing loss. Objectives: This case-control study compared the prevalence of hearing loss in a sample of diabetics with that in an age and sex matched group of healthy controls. Methods: Cases were consecutively selected from the diabetics registered in two diabetes centers during February to December 2013. Controls were age and sex matched healthy volunteers admitted to a blood bank. Pure tone audiometric test (PTA) was performed by audiometer for the evaluation of hearing impairment. Then, the existence of hearing impairment in different intensities was compared between the two groups considering the effect of diabetes duration, BMI, and serum creatinine (Cr) level. Results: Eighty diabetics and eighty healthy controls were included. Hearing loss in sounds with high frequencies was more common in the diabetics than the controls. The mean serum creatinine level was significantly higher in the diabetics with hearing loss than those without hearing loss at noise frequencies of 4 KHz and 8 KHz (P < 0.05). Meanwhile, hemoglobin A1C, duration of diabetes, and body mass index were not associated with hearing loss. Conclusions: According to the results, hearing impairment in high frequency sounds was more common in the diabetics than the healthy individuals. Also, the severity of hearing loss in patients with diabetes was associated with the levels of creatinine (diabetic nephropathy). The hypothesis of the relationship between diabetes and hearing loss through nephropathy should be more examined in future studies

Acoustic Behavior of Hollow Blocks and Bricks Made of Concrete Doped with Waste-Tire Rubber.

In this paper, we investigate the acoustic behaviour of building elements made of concrete doped with waste-tire rubber. Three different mixtures were created, with 0%, 10%, and 20% rubber in their composition. Bricks, lattice joists, and hollow blocks were manufactured with each mixture, and three different cells were built and tested against aerial and impact noise. The values of the global acoustic isolation and the reduction of the sound pressure level of impacts were measured. Results proved that highly doped elements are an excellent option to isolate low frequency sounds, whereas intermediate and standard elements constitute a most interesting option to block middle and high frequency sounds. In both cases, the considerable amount of waste-tire rubber recycled could justify the employment of the doped materials for the sake of the environment.

A Conceptual Study of Karnapooran In Prevention of Nihl (Noise Induced Hearing Loss)

Noise-induced hearing loss limit ability to hear high frequency sounds, understand speechand seriously impairs ability to communicate. The effects of hearing loss can be profound, as hearing losscan interfere with ability to enjoy socializing with friends, playing with your children or grandchildren, orparticipating in other social activities you enjoy, and can lead to psychological and social isolation. Highfrequency sound damage to the microscopic hair cells found inside the cochlea. Damage of cell is creatinghearing loss. Karnapoorna reduce the frequency of sound also smoothing the pathway and which ultimatereduce the risk factor of hearing loss. Karnapooran is a one of the best procedure for the Noise-inducedhearing loss (NIHL).

Intracortical depth analyses of frequency-sensitive regions of human auditory cortex using 7T fMRI

Despite recent advances in auditory neuroscience, the exact functional organization of human auditory cortex (AC) has been difficult to investigate. Here, using reversals of tonotopic gradients as the test case, we examined whether human ACs can be more precisely mapped by avoiding signals caused by large draining vessels near the pial surface, which bias blood-oxygen level dependent (BOLD) signals away from the actual sites of neuronal activity. Using ultra-high field (7T) fMRI and cortical depth analysis techniques previously applied in visual cortices, we sampled 1mm isotropic voxels from different depths of AC during narrow-band sound stimulation with biologically relevant temporal patterns. At the group level, analyses that considered voxels from all cortical depths, but excluded those intersecting the pial surface, showed (a) the greatest statistical sensitivity in contrasts between activations to high vs. low frequency sounds and (b) the highest inter-subject consistency of phase-encoded continuous tonotopy mapping. Analyses based solely on voxels intersecting the pial surface produced the least consistent group results, even when compared to analyses based solely on voxels intersecting the white-matter surface where both signal strength and within-subject statistical power are weakest. However, no evidence was found for reduced within-subject reliability in analyses considering the pial voxels only. Our group results could, thus, reflect improved inter-subject correspondence of high and low frequency gradients after the signals from voxels near the pial surface are excluded. Using tonotopy analyses as the test case, our results demonstrate that when the major physiological and anatomical biases imparted by the vasculature are controlled, functional mapping of human ACs becomes more consistent from subject to subject than previously thought.

Some flying animals that generate aversion to humans are the bats.

The incredible faculty of perception of the bat is vinculated to their system of ubication by means of eco resonance so; they are oriented by emitting high frequency sounds orientation, and receipting the echoes. In thaws way, detecting the objetcs around them, Perceiving one antennae no more of 1 mm of diameter, insects of size of a mosquito and objects as thin a human hair.

Perception of speech in cartilage conduction.

By attaching a transducer to the aural cartilage a relatively loud sound is audible even with a negligibly small fixation pressure applied to the transducer. This form of conduction is referred to as cartilage conduction (CC). Utilizing CC, novel audio devices can be developed, and one possible application is a CC hearing aid. However, there are no studies on speech perception in CC. In this study, CC speech recognition performance was measured and compared with that for air and bone conduction (AC and BC, respectively). Nine volunteers with normal hearing participated in the study. The performance-intensity functions were measured for AC, BC and CC. These measurements were performed in the conditions with and without an earplug. Without the earplug, no differences in speech recognition scores were observed among AC, BC, and CC. With the earplug, the level at which the maximum speech recognition score was obtained did not increase in CC, which agreed with the result of BC but not AC. The maximum speech recognition CC score decreased with the earplug. The performance-intensity functions for AC and BC shifted in parallel with the earplug. These shifts approximated the average threshold shifts. In contrast, for CC, the performance-intensity function did not shift in parallel with the earplug. As for the CC threshold shifts with the earplug, although the threshold at 500Hz decreased by 15.4dB, those at 2000 and 4000Hz increased by 13.8 and 31.1dB, respectively. Compared with AC and BC, CC excessively emphasized low over high frequency sounds when the earplug was inserted. Confusion matrices analysis demonstrated that 4%, 22%, and 74% of the errors occurred at low, intermediate, and high frequency speech sounds, respectively. Thus, this excessive low frequency sound emphasis probably prevented the recognition of high frequency speech sounds. The decrease in the maximum speech recognition score for CC with the earplug was derived from the biased frequency composition. It can be improved by frequency composition adjustment.

The risk factors of hearing loss in diabetes mellitus

Background: Hearing loss is considered as one of the complications in diabetic patients. However, studies reported conflicting results on the relationship between diabetes and hearing loss. Objectives: This study aimed to investigateand compare the prevalence of hearing loss in patients with diabetes mellitus and a group of non-diabetic people. Materials and Methods: This study was conducted on 80 patients with diabetes and 80 non-diabetic subjects.Subjects in the case group were selected among the diabetic patients registered in the diabetes centers of Isfahanprovince. Subjects in the control group were selected among non-diabetic individuals referring to the blood bank todonate blood. The instrument used for data collection included of questions on the subjects demographics and a special form for recording the results of the subjects’ laboratory examinations including HbA1c, TSH, Cr and theresult of the audiometric examinations. Data analysis was performed using descriptive statistics, chi-square test andt-test or nonparametric equivalents. Results: Compared with non-diabetic subjects, hearing loss in sounds with high frequencies was more common in patients with diabetes (P value = 0.001), the mean creatinine was significantly different in diabetic patients with and without hearing loss at noise frequencies of 4 KHz and 8 KHz (P value< 0.05). However, hemoglobin A1C, duration of diabetes and BMI were not significantly associated with hearing loss. Conclusion: Hearing impairment in high frequency sounds is more common in diabetics than healthy individuals.The severity of hearing loss in patients with diabetes is also associated with the levels of creatinine. Keywords: Hearing Loss, Diabetes mellitus, Audiometry

Detection of auditory signals in quiet and noisy backgrounds while performing a visuo-spatial task.

Context:The ability to detect important auditory signals while performing visual tasks may be further compounded by background chatter. Thus, it is important to know how task performance may interact with background chatter to hinder signal detection.Aim:To examine any interactive effects of speech spectrum noise and task performance on the ability to detect signals.Settings and Design:The setting was a sound-treated booth. A repeated measures design was used.Materials and Methods:Auditory thresholds of 20 normal adults were determined at 0.5, 1, 2 and 4 kHz in the following conditions presented in a random order: (1) quiet with attention; (2) quiet with a visuo-spatial task or puzzle (distraction); (3) noise with attention and (4) noise with task.Statistical Analysis:Multivariate analyses of variance (MANOVA) with three repeated factors (quiet versus noise, visuo-spatial task versus no task, signal frequency).Results:MANOVA revealed significant main effects for noise and signal frequency and significant noise–frequency and task–frequency interactions. Distraction caused by performing the task worsened the thresholds for tones presented at the beginning of the experiment and had no effect on tones presented in the middle. At the end of the experiment, thresholds (4 kHz) were better while performing the task than those obtained without performing the task. These effects were similar across the quiet and noise conditions.Conclusion:Detection of auditory signals is difficult at the beginning of a distracting visuo-spatial task but over time, task learning and auditory training effects can nullify the effect of distraction and may improve detection of high frequency sounds.

Successful combination treatment of a bifocal secretory germinoma with brain stem compression in a 17-year-old girl

A 17-year-old girl, evaluated since 2007 for endocrinological disorders due to secondary amenorrhea and weight loss, was referred to the neurosurgery department in May 2011 due to symptoms of rapidly increasing intracranial pressure. Computed tomography revealed a bifocal, irregular, non-homogeneous tumour localised in pineal and suprasellar regions (Figures 1 A, B). Immediate septostomy, ventriculo-peritoneal valve implantation and suprasellar tumour biopsy were performed. Histopathological examination confirmed the tumour to be a secretory type germinoma (β-HCG = 0.696 mIU/ml; AFP = 79.89 µg/ml in serum). After surgical biopsy (Figure 1 C) the chemotherapy was introduced according to the GCT SIOP96 protocol – which is the standard protocol for children in Poland with this diagnosis. The control magnetic resonance imaging (MRI) confirmed total regression of the suprasellar tumour and a residual pineal mass (Figure 1 D). At the end of July 2011 the patient was transferred to the Radiotherapy Department for treatment planning. Radiation therapy was initiated using both static and dynamic fields, including 3 target volumes (Figure 1 E): brain ventricles (blue) irradiated up to 30.6 Gy, PTV2 (cyan) – both tumour loci – up to 45.0 Gy with dose escalation on the pineal tumour residue up to 52.2 Gy (turquoise). Currently the patient is in 3.5-year follow-up (Figure 1 F) in a good clinical condition, presenting only minor left-sided convergent strabismus, slight deafness for high frequency sounds and requires hormonal supplementation. The last MRI revealed only a residual mass in the pineal region 10 × 7 × 12 mm and a “flat” pituitary gland as deviations from the normal condition. Figure 1 A, B – Transverse and sagittal computed tomography scans before initiation of treatment of pineal (38 × 30 × 30 mm) and suprasellar regions (25 × 20 × 20 mm), C – MRI scan after the surgical procedure, ... Intracranial germ cell tumours (GCTs) account for 1–2% of all primary paediatric central nervous system (CNS) tumours and have a peak incidence at between 10 and 14 years with a male-female ratio of 2 : 1 [1]. Although multiple loci at presentation are associated with poorer prognosis [2], in this relatively unusual case, despite dramatic onset of symptoms, the treatment has proven successful thus far. Up to 20% of intracranial GCTs are multifocal, and they usually involve the suprasellar and pineal gland region. This is typically observed in adolescent males rather than females. Pineal GCTs induce acute symptoms of intracranial pressure which may be manifested by the classic triad of chronic symptoms: diabetes insipidus, visual deficits and precocious or delayed sexual maturity [3]. Evaluation must include MRI of the brain and serum marker levels (AFP, β-HCG) should be obtained. Biopsy sampling is recommended in all cases nowadays. Surgical treatment of intracranial GCTs remains controversial. Limited volume radiation therapy (whole ventricle followed by boost for residual tumour) is an important part of treatment preceded by chemotherapy according to currently used protocols. Endocrinopathies are a common complication of treating brain GCTs [4]. If pituitary gland insufficiency persists, it may however be easily corrected by hormonal treatment. The potential late sequelae due to chemotherapy and radiotherapy do not generally impair future mental and social development in adolescents, which gives a chance for a good quality of life in the future for these patients [5]. However, in younger patients, persistent neurological deficiencies resulting from surgical and radiotherapeutic complications may be a serious issue [4, 5].

A comparison between neural response telemetry via cochleostomy or the round window approach in cochlear implantation

There are two techniques for cochlear implant (CI) electrode placement: cochleostomy and the round window (RW) approach.Objective: This study aims to compare neural response telemetry (NRT) results immediately after surgery to check for possible differences on auditory nerve stimulation between these two techniques.Materials and Methods: This is a prospective cross-sectional study. Twenty-three patients were enrolled. Six patients underwent surgery by cochleostomy and 17 had it through the RW approach.Results: Mean charge units (MCU) for high frequency sounds: patients submitted to the RW approach had a mean value of 190.4 (±29.2) while cochleostomy patients averaged 187.8 (±32.7); p = 0.71. MCU for mid frequency sounds: patients submitted to the RW approach had a mean value of 192.5 (±22) while cochleostomy patients averaged 178.5 (±18.5); p = 0.23. MCU for low frequency sounds: patients submitted to the RW approach had a mean value of 183.3 (±25) while cochleostomy patients averaged 163.8 (±19.3); p = 0.19.Conclusion: This study showed no differences in the action potential of the distal portion of the auditory nerve in patients with multichannel cochlear implants submitted to surgery by cochleostomy or through the RW approach, using the implant itself to generate stimuli and record responses. Both techniques equally stimulate the cochlear nerve. Therefore, the choice of approach can be made based on the surgeon's own preference and experience.