scholarly journals Over-the-Counter Hearing Aids: A Lost Decade for Change

2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Zoe Yee Ting Chan ◽  
Bradley McPherson
Keyword(s):  
Hearing Aids ◽  
Control Function ◽  
Low Cost ◽  
Low Frequency ◽  
Volume Control ◽  
Elderly Persons ◽  
Over The Counter ◽  
Input Noise ◽  
Irregular Frequency ◽  
Equivalent Input Noise

Background. Hearing aids sold directly to consumers in retail stores or through the internet, without individual prescription by audiological professionals, are termed over-the-counter (OTC) devices. This study aimed to determine whether there was any change in the electroacoustic characteristics of OTC devices compared to research carried out a decade earlier. The previous results indicated that most OTC devices were low-frequency-emphasis devices and were unsuitable for elderly people with presbycusis, who were likely to be the major consumers of these products.Methods. Ten OTC devices were selected and their electroacoustic performance was measured. Appropriate clients for the OTC devices were derived, using four linear prescription formulae, and OTC suitability for elderly persons with presbycusis was investigated.Results. OTC electroacoustic characteristics were similar to those in the earlier study. Most OTC devices were not acoustically appropriate for potential consumers with presbycusis. Although several of the devices could match prescriptive targets for individuals with presbycusis, their poor electroacoustic performance—including ineffective volume control function, high equivalent input noise, and irregular frequency response—may override their potential benefit.Conclusion. The low-cost OTC devices were generally not suitable for the main consumers of these products, and there has been little improvement in the appropriateness of these devices over the past decade.

Electroacoustic Performance of Direct-Input Hearing Aids with FM Amplification Systems

1990 ◽  
Vol 21 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Linda M. Thibodeau
Keyword(s):  
Hearing Aids ◽  
Sound Pressure ◽  
Harmonic Distortion ◽  
Pressure Level ◽  
Volume Control ◽  
High Frequencies ◽  
Input Noise ◽  
Practical Information ◽  
Direct Input ◽  
Equivalent Input Noise

The purpose of this paper was to provide audiologists practical information regarding the use of direct-input hearing aids with FM systems. The degree to which the electroacoustic characteristics of direct-input hearing aids were preserved when used with two different personal FM systems was evaluated. Although there were limited changes in saturation sound pressure level and harmonic distortion, there was an increase in equivalent-input noise and full-on-gain. The frequency response curve of the aid + FM condition relative to the aid alone differed in the high frequencies for the two FM systems. Aids with equivalent gain values had varying amounts of gain when tested with the FM systems set at a constant volume control setting. This variability in the electroacoustic response of a given aid when coupled to a personal FM system suggests that one may not assume characteristics of the hearing aid are maintained when it is used with an FM system.

Do Modern Hearing Aids Meet ANSI Standards?

2016 ◽  
Vol 27 (08) ◽  
pp. 619-627 ◽  
Author(s):  
Jourdan T. Holder ◽  
Erin M. Picou ◽  
Jill M. Gruenwald ◽  
Todd A. Ricketts
Keyword(s):  
Quality Control ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Analysis Data ◽  
National Standards ◽  
Control Measures ◽  
Input Noise ◽  
Release Times ◽  
Quality Control Testing ◽  
Equivalent Input Noise

Background: The American National Standards Institute (ANSI) provides standards used to govern standardization of all hearing aids. If hearing aids do not meet specifications, there are potential negative implications for hearing aid users, professionals, and the industry. Recent literature has not investigated the proportion of new hearing aids in compliance with the ANSI specifications for quality control standards when they arrive in the clinic before dispensing. Purpose: The aims of this study were to determine the percentage of new hearing aids compliant with the relevant ANSI standard and to report trends in electroacoustic analysis data. Research Design: New hearing aids were evaluated for quality control via the ANSI S3.22-2009 standard. In addition, quality control of directional processing was also assessed. Study Sample: Seventy-three behind-the-ear hearing aids from four major manufacturers, that were purchased for clinical patients were evaluated before dispensing. Data Collection and Analysis: Audioscan Verifit (version 3.1) hearing instrument fitting system was used to complete electroacoustic analysis and directional processing evaluation of the hearing aids. Frye’s Fonix 8000 test box system (Fonix 8000) was also used to cross-check equivalent input noise (EIN) measurements. These measurements were then analyzed for trends across brands and specifications. Results: All of the hearing aids evaluated were found to be out of specification for at least one measure. EIN and attack and release times were the measures most frequently out of specification. EIN was found to be affected by test box isolation for two of the four brands tested. Systematic discrepancies accounted for ˜93% of the noncompliance issues, while unsystematic quality control issues accounted for the remaining 7%. Conclusions: The high number of systematic discrepancies between the data collected and the specifications published by the manufacturers suggests there are clear issues related to the specific protocols used for quality control testing. These issues present a significant barrier for hearing aid dispensers when attempting to accurately determine if a hearing aid is functioning appropriately. The significant number of unsystematic discrepancies supports the continued importance of quality control measures of new and repaired hearing aids to ensure that the device is functioning properly before it is dispensed and to avoid future negative implications of fitting a faulty device.

scholarly journals A Compact Low-Distortion Low-Power Instrumentation Amplifier

2010 ◽  
Vol 5 (1) ◽  
pp. 33-41
Author(s):  
Jader A. De Lima
Keyword(s):  
Low Frequency ◽  
Design Parameters ◽  
Instrumentation Amplifier ◽  
Cmos Process ◽  
Output Stage ◽  
Noise Spectral Density ◽  
Class Ab ◽  
Input Noise ◽  
Low Distortion ◽  
Equivalent Input Noise

A CMOS instrumentation amplifier based on a simple topology that comprises a double-input Gm-stage and a low-distortion class-AB output stage is presented. Sub-threshold design techniques are applied to attain high figures of differential-gain and rejection parameters. Analyses of input-referred noise and CMRR are comprehensively carried out and their dependence on design parameters determined. The prototype was fabricated in standard n-well CMOS process. For 5V-rail-to-rail supply and bias current of 100nA, stand-by consumption is only 16μW. Low-frequency parameters are ADM=86dB, CMRR=89.3dB, PSRR+=87dB, PSRR-=74dB. For a 6.5pF-damping capacitor, ΦM=73º and GBW=47KHz. The amplifier exhibits a THD of –64.5dB @100Hz for a 1Vpp-output swing. Input-noise spectral density is 5.2μV/ Hz @1Hz and 1.9μV/ Hz @10Hz, which gives an equivalent input-noise of 37.6μV, over 1Hz-200Hz bandwidth. This circuit may be employed for low-frequency, low-distortion signal processing, advantageously replacing the conventional 3-opamp approach for instrumentation amplifiers.

A high-resolution tunneling magneto-resistance sensor interface circuit

2017 ◽  
Vol 31 (04) ◽  
pp. 1750030 ◽  
Author(s):  
Xiangyu Li ◽  
Liang Yin ◽  
Weiping Chen ◽  
Zhiqiang Gao ◽  
Xiaowei Liu
Keyword(s):  
Band Gap ◽  
Temperature Coefficient ◽  
Low Frequency ◽  
Low Noise ◽  
Instrumentation Amplifier ◽  
Interface Circuit ◽  
Input Noise ◽  
Rejection Ratio ◽  
Equivalent Input Noise ◽  
Magneto Resistance

In this paper, a chopper instrumentation amplifier and a high-precision and low-noise CMOS band gap reference in a standard 0.5 [Formula: see text] CMOS technology for a tunneling magneto-resistance (TMR) sensor is presented. The noise characteristic of TMR sensor is an important factor in determining the performance of the sensor. In order to obtain a larger signal to noise ratio (SNR), the analog front-end chip ASIC weak signal readout circuit of the sensor includes the chopper instrumentation amplifier; the high-precision and low-noise CMOS band gap reference. In order to achieve the low noise, the chopping technique is applied in the first stage amplifier. The low-frequency flicker noise is modulated to high-frequency by chopping switch, so that the modulator has a better noise suppression performance at the low frequency. The test results of interface circuit are shown as below: At a single 5 V supply, the power dissipation is 40 mW; the equivalent offset voltage is less than 10 uV; the equivalent input noise spectral density 30 nV/Hz[Formula: see text](@10 Hz), the equivalent input noise density of magnetic is 0.03 nTHz[Formula: see text](@10 Hz); the scale factor temperature coefficient is less than 10 ppm/[Formula: see text]C, the equivalent input offset temperature coefficient is less than 70 nV/[Formula: see text]C; the gain error is less than 0.05%, the common mode rejection ratio is greater than 120 dB, the power supply rejection ratio is greater than 115 dB; the nonlinear is 0.1% FS.

scholarly journals Disruptive Hearing Technologies and Mild Sensorineural Hearing Loss II: Current Research on Affordable Hearing Technologies and Direct-to-Consumer Models

2018 ◽  
Vol 39 (02) ◽  
pp. 146-157 ◽  
Author(s):  
Carole Johnson ◽  
Jeffrey Danhauer ◽  
Anna Jilla
Keyword(s):  
Hearing Loss ◽  
Service Delivery ◽  
Hearing Aids ◽  
Low Cost ◽  
Field Trials ◽  
Over The Counter ◽  
Direct To Consumer ◽  
Service Delivery Models ◽  
Delivery Models ◽  
Moderate Hearing Loss

AbstractRecently, President Trump signed into law the Food and Drug Administration (FDA) Reauthorization Act of 2017, which included the Over-the-Counter Hearing Aid Act designed to provide greater public accessibility to and affordability of amplification for individuals with self-identified mild and moderate hearing loss through the provision of over-the-counter (OTC) hearing aids (HAs) with a direct-to-consumer (DTC) delivery model. American Speech-Language-Hearing Association and American Academy of Audiology Position Statements on OTC HAs state that these devices should only be used for adults with mild hearing losses. DTC amplification and service delivery has been available to consumers in a variety of forms for a significant period of time. However, FDA-regulated OTC HAs will not be available as described in the new law until the FDA publishes the required guidance related to the technology, safety, and labeling of such devices. With the clear similarities in mind between present and future amplification options, a literature search was conducted to review studies assessing outcomes for low-cost and DTC HAs and service-delivery models to inform what we may expect as OTC HAs enter the market. Nine studies were identified which assessed: (1) electroacoustic capabilities of low-cost and DTC HAs, (2) use of these devices in field trials, or (3) efficacy of DTC models. None of the studies reported outcomes specifically for participants with mild hearing loss. The studies had poor external validity because none included all factors that would exist in realistic uses of OTC HAs within a DTC model. Additional research will be needed as OTC HAs become available and different delivery models are proposed.

Evaluation of Special Hearing Aids for Deaf Children

1971 ◽  
Vol 36 (4) ◽  
pp. 527-537 ◽  
Author(s):  
Norman P. Erber
Keyword(s):  
Hearing Aids ◽  
High Frequency ◽  
Hearing Aid ◽  
Low Frequency ◽  
Acoustic Stimulation ◽  
Deaf Children ◽  
Frequency Range ◽  
Frequency Limit ◽  
Unpublished Studies ◽  
Published Research

Two types of special hearing aid have been developed recently to improve the reception of speech by profoundly deaf children. In a different way, each special system provides greater low-frequency acoustic stimulation to deaf ears than does a conventional hearing aid. One of the devices extends the low-frequency limit of amplification; the other shifts high-frequency energy to a lower frequency range. In general, previous evaluations of these special hearing aids have obtained inconsistent or inconclusive results. This paper reviews most of the published research on the use of special hearing aids by deaf children, summarizes several unpublished studies, and suggests a set of guidelines for future evaluations of special and conventional amplification systems.

scholarly journals Patients in intensive care unit for COVID-19 pneumonia: the lung ultrasound patterns at admission and discharge. An observational pilot study

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Persona Paolo ◽  
Valeri Ilaria ◽  
Zarantonello Francesco ◽  
Forin Edoardo ◽  
Sella Nicolò ◽  
...  
Keyword(s):  
Intensive Care ◽  
Lung Ultrasound ◽  
Low Cost ◽  
Low Frequency ◽  
Specific Pattern ◽  
University Hospital ◽  
Left Hemithorax ◽  
Significant Difference ◽  
The Right ◽  
B Lines

Abstract Background During COVID-19 pandemic, optimization of the diagnostic resources is essential. Lung Ultrasound (LUS) is a rapid, easy-to-perform, low cost tool which allows bedside investigation of patients with COVID-19 pneumonia. We aimed to investigate the typical ultrasound patterns of COVID-19 pneumonia and their evolution at different stages of the disease. Methods We performed LUS in twenty-eight consecutive COVID-19 patients at both admission to and discharge from one of the Padua University Hospital Intensive Care Units (ICU). LUS was performed using a low frequency probe on six different areas per each hemithorax. A specific pattern for each area was assigned, depending on the prevalence of A-lines (A), non-coalescent B-lines (B1), coalescent B-lines (B2), consolidations (C). A LUS score (LUSS) was calculated after assigning to each area a defined pattern. Results Out of 28 patients, 18 survived, were stabilized and then referred to other units. The prevalence of C pattern was 58.9% on admission and 61.3% at discharge. Type B2 (19.3%) and B1 (6.5%) patterns were found in 25.8% of the videos recorded on admission and 27.1% (17.3% B2; 9.8% B1) on discharge. The A pattern was prevalent in the anterosuperior regions and was present in 15.2% of videos on admission and 11.6% at discharge. The median LUSS on admission was 27.5 [21–32.25], while on discharge was 31 [17.5–32.75] and 30.5 [27–32.75] in respectively survived and non-survived patients. On admission the median LUSS was equally distributed on the right hemithorax (13; 10.75–16) and the left hemithorax (15; 10.75–17). Conclusions LUS collected in COVID-19 patients with acute respiratory failure at ICU admission and discharge appears to be characterized by predominantly lateral and posterior non-translobar C pattern and B2 pattern. The calculated LUSS remained elevated at discharge without significant difference from admission in both groups of survived and non-survived patients.

Reliability and Stability of Various Hearing-Aid Outcome Measures in a Group of Elderly Hearing-Aid Wearers

1996 ◽  
Vol 39 (5) ◽  
pp. 923-935 ◽  
Author(s):  
Larry E. Humes ◽  
Dan Halling ◽  
Maureen Coughlin
Keyword(s):  
Outcome Measures ◽  
Hearing Aids ◽  
Repeated Measures ◽  
Nonsense Syllable ◽  
Hearing Aid ◽  
Objective Measure ◽  
The Elderly ◽  
Elderly Persons ◽  
Hearing Aid Use ◽  
Hearing Handicap

Twenty elderly persons with hearing impairment were fit with binaural in-the-ear hearing aids and followed for a 6-month period post-fit. Several hearing-aid outcome measures were obtained at 0, 7, 15, 30, 60, 90, and 180 days post-fit. Outcome measures included (a) objective measures of benefit obtained with nonsense-syllable materials in quiet (CUNY Nonsense Syllable Test, NST) and sentences in multitalker babble (Hearing in Noise Test, HINT); (b) two subjective measures of benefit, one derived from pre-fit/post-fit comparisons on a general scale of hearing handicap (Hearing Handicap Inventory for the Elderly, HHIE) and the other based on a subjective scale of post-fit hearing-aid benefit (Hearing Aid Performance Inventory, HAPI); (c) a questionnaire on hearing-aid satisfaction; (d) an objective measure of hearing-aid use; and (e) a subjective measure of hearing-aid use. Reliability and stability of each measure were examined through repeated-measures analyses of variance, a series of test-retest correlations, and, where possible, scatterplots of the scores against their corresponding 95% critical differences. Many of the measures were found to be both reliable and stable indicators of hearing-aid outcome.

Cytyzyna w terapii zaprzestania palenia tytoniu

2020 ◽  
Vol 23 (2) ◽  
Author(s):  
Patrycjusz Kołodziejczyk ◽  
Katarzyna Baranowska-Kempisty ◽  
Piotr Bernat ◽  
Piotr Tutka
Keyword(s):  
Smoking Cessation ◽  
Adverse Events ◽  
Nicotinic Receptor ◽  
Receptor Agonist ◽  
Addiction Treatment ◽  
Causes Of Death ◽  
Low Frequency ◽  
Duration Of Treatment ◽  
Over The Counter ◽  
Natural Plant

Tobacco smoking is one of the leading causes of death among people. Cytisine, a plant alkaloid considered to be the oldest medication for smoking cessation, has been used in Poland since the 1970s. The drug is a partial nicotinic receptor agonist, with pharmacological actions close to those of nicotine and varenicline (a synthetic cytisine derivative and most expensive smoking cessation medication currently available). Cytisine has several advantages compared to existing smoking cessation drugs, including: 1) it is more effective than placebo and nicotine replacement therapy, and at least as effective as varenicline, 2) its use is associated with a low frequency of adverse events, 3) it is available as over the counter medicine and is much cheaper than other smoking cessation drugs that are cost-prohibitive, 4) it derives from a natural plant and may be preferred by smokers who do not want to use other treatments, 5) it has shorter duration of treatment (i.e. 25 days) compared to other medicines for smoking cessation. This review describes the use of cytisine for nicotine addiction treatment, mechanism of anti-smoking action, pharmacokinetics, efficacy, tolerability and safety.

scholarly journals An EEG Experimental Study Evaluating the Performance of Texas Instruments ADS1299

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3721 ◽  
Author(s):  
Usman Rashid ◽  
Imran Niazi ◽  
Nada Signal ◽  
Denise Taylor
Keyword(s):  
Experimental Study ◽  
Mixed Models ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Low Frequency ◽  
Low Power Consumption ◽  
Motor Tasks ◽  
Negative Peak ◽  
Eeg Data ◽  
Healthy Participants

Texas Instruments ADS1299 is an attractive choice for low cost electroencephalography (EEG) devices owing to its low power consumption and low input referred noise. To date, there have been no rigorous evaluations of its performance. In this EEG experimental study we evaluated the performance of the ADS1299 against a high quality laboratory-based system. Two self-paced lower limb motor tasks were performed by 22 healthy participants. Recorded power across delta, theta, alpha, and beta EEG bands, the power ratio across the motor tasks, pre-movement noise, and signal-to-noise ratio were obtained for evaluation. The amplitude and time of the negative peak in the movement-related cortical potentials (MRCPs) extracted from the EEG data were also obtained. Using linear mixed models, no statistically significant differences (p > 0.05) were found in any of these measures across the two systems. These findings were further supported by evaluation of cosine similarity, waveform differences, and topographic maps. There were statistically significant differences in MRCPs across the motor tasks in both systems. We conclude that the performance of the ADS1299 in combination with wet Ag/AgCl electrodes is analogous to that of a laboratory-based system in a low frequency (<40 Hz) EEG recording.

Sign in / Sign up

Export Citation Format

Share Document