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E R Harford

Publications and source records attributed to E R Harford.

16 recordsLinked to original sources
PubMed1983

Tympanometry.

Explore the source record for details and available documents.

Acoustic Impedance Tests↗
PubMed1983

Children with persistent otitis media. Audiometric and tympanometric findings.

Audiometric and tympanometric findings were compared among 129 patients with clinically manifest persistent otitis media (OM) with effusion. Ears with thick effusion (mucoid OM) had significantly larger air-bone gaps and higher prevalence of flat tympanograms than either of the thin effusion types (purulent [POM] or serous OM [SOM]) or ears with no effusion (dry). Ears with thin effusion (POM and SOM) had similar air-bone gaps, thresholds for air and bone conduction, and prevalences of flat and underpressure tympanograms. Ears with no effusion had significantly smaller air-bone gaps, slightly poorer bone conduction thresholds, and lower prevalence of flat tympanograms than ears with effusion (MOM, POM and SOM). Ears with clinically manifest OM and no effusion at tympanocentesis appear to represent patients with a spontaneously resolved episode of OM with thin effusion (POM or SOM) or with ears that evacuated during anesthesia prior to tympanostomy.

Acoustic Impedance Tests↗
PubMed1981

A new clinical technique for verification of hearing aid response.

A new miniature wide-range electret microphone with a flat frequency response is available to the audiology clinic to measure sound pressure in the patient's ear canal. This article describes the clinical application of this new microphone for the selection and monitoring of hearing aid response. Preliminary results of the relationship between ear canal measurements and functional gain are also provided. This new clinical technique can provide the audiologist with quick objective data on the response of a hearing aid while it is being worn by the patient.

Acoustics↗
PubMedDate not supplied

The use of a miniature microphone in the ear canal for the verification of hearing aid performance.

An individual head, auricle, and ear canal can alter signals from a hearing aid other sources of acoustic stimulation compared to artificial couplers. The most realistic method for quantifying or verifying certain parameters of acoustic simulation delivered to the ear by a hearing aid is to measure the sound pressure level of a signal in the ear canal of an individual while wearing an aid. Probe microphone measurements have been conducted and reported for the past 33 years. Until now, such microphone measurements have used a hollow tube inserted into the ear canal which leads to a transducer outside the canal. This paper describes our preliminary clinical application of a new wide range, flat response, miniature electret microphone, measuring 4 x 5 x 2 mm for measurement of insertion gain in a patient's ear canal. We believe the information from these recordings can be useful in developing objective clinical procedures for the selection and monitoring of wearable amplification for hearing-impaired patients.

Acoustics↗
PubMedDate not supplied

Hearing status of ambulatory senior citizens.

The objective of this paper is to provide some current data on the hearing sensitivity for pure-tone stimuli for a population of ambulatory, noninstitutionalized Caucasian males and females 60 years and older. Data pertaining to four areas of hearing status are reported, i.e., the average puretone audiometric characteristic, sex differences, changes with age, and a comparison with institutionalized persons of similar age. Our results indicate that the typical audiometric configuration is a symmetrical gradual roll-off in the higher audiometric frequencies rarely averaging in the speech range more than 55 dB regardless of age. Hearing levels for men and women differ somewhat between 60 and 80 years and then become quite similar. Hearing sensitivity does decrease with age and between 70 and 80 years it decreases about 1.5 dB per year. Finally, as one might expect, active ambulatory older people have better hearing sensitivity than those of the same age who are in nursing homes.

Age Factors↗
PubMedDate not supplied

A community hearing conservation program for senior citizens.

A commnity hearing conservation program for more than 1000 senior citizens is described. Seminars about hearing loss, hearing aids were conducted. Results of hearing tests under various conditions are drawn from a population of more than 500 senior adults. Information about hearing aid use and self-awareness regarding hearing impairment was also collected. It is concluded that senior citizens arae very interested in learning more about hearing loss and treatment, but as a group they are reluctant to seek out remediation voluntarily. Thus, it appears that outreach programs are important considerations for serving the ambulatory senior population. It is concluded that it is highly feasible to obtain dependable pure-tone audiometric data in field locations with some minor precautions. In our opinion, audiological services should be taken to populations of senior citizens, provided they can be cost effective. Some suggestions are offered for improving the type of program described in this paper.

Adult↗
PubMedDate not supplied

Predictability of real ear hearing aid performance from coupler measurements.

Results comparing hearing aid performance utilizing probe microphones with performance measured in a commercial hearing aid test box using an HA-2 coupler are presented. Sixteen hearing-impaired subjects (23 ears) were divided into two groups. Group I utilized unvented earmolds with short canals and large bores; group II utilized unvented earmolds with long canals and small bores. Results revealed that large individual differences across frequencies as well as within and between groups preclude predicting how a hearing aid will perform on a real ear from test box measurements.

Acoustics↗
PubMedDate not supplied

The pediatric audiologist: from magician to clinician.

The tremendous progress of pediatric-audiology during the past 30 years is reviewed. Early identification of infants with impaired hearing is based on a high-risk register, screening behaviorally and/or brain stem audiometry. Since many hearing losses have a late onset, it is important to cooperate closely with pediatricians and well-baby clinics. To stimulate their interest in detection, use of a calibrated 3000 Hz warble tone instrument is suggested. Diagnostic tests for infants involve respiration, behavioral patterns, middle ear impedance, and brain stem audiometry. For young children, tangible reinforcement operant conditioning audiometry (TROCA) visual reinforcement audiometry (VRA), and play audiometry are the methods of choice. Due to medical progress, many of the high-risk factors have been ameliorated. Assessment of amplification for hearing impaired children is as sophisticated as for adults. The advantage of basing fitting procedures on functional gain is emphasized. Future goals in pediatric audiology are touched upon. Today, pediatric audiology has emerged from a mysterious beginning to a systematic clinical specialization.

Audiology↗
PubMedDate not supplied

Tympanometric configurations and middle ear findings in experimental otitis media.

Relationships between ventilation of the middle ear (ME) system and pathogenic bacteria in the upper respiratory tract were explored in an animal model to better understand the etiopathogenesis of otitis media. Otitis media developed in 12 of 18 chinchillas inoculated intranasally with Streptococcus pneumoniae followed by bilateral ME deflation (negative pressure). Otitis media with effusion developed in 19 of 36 ears examined ten days after inoculation. The development of purulent effusion after ten days was highly correlated with persistent negative ME pressure for at least 48 hours after deflation, while most ears that developed serous effusion after ten days had normal ME pressure 48 hours after deflation. Tympanometric validation of the presence of absence of effusion and type of effusion was obtained ten days after inoculation. A low compliance tympanogram detected 90% of the purulent effusions and was 100% specific for this type of effusion. In contrast. three of four serous effusions were associated with normal pressure/normal compliance tracings suggesting that the physical characteristics or volume of ME effusion and/or the histopathology of the ME cleft are reflected i the tympanometric configuration.

Acoustic Impedance Tests↗
PubMedDate not supplied

The use of high-pass amplification for broad-frequency sensorineural hearing loss.

Recent research suggests that persons with sensorineural hearing impairment should derive extra benefit from amplification that eliminates or greatly reduces low frequencies, i.e. frequencies below 1 500 or 2 000 Hz. Such amplification seems to reduce the detrimental effects of the upward spread of masking on speech intelligibility, especially when listening in noisy environments. Also, current research indicates that extended high-frequency amplification, between 4 000 and 6 500 Hz is especially beneficial for optimal speech intelligibility. 9 patients with a relatively flat, moderate to severe sensorineural hearing loss were evaluated in the clinic and for daily listening situations while wearing conventional broad-frequency hearing aids with an upper range of about 4 500 Hz. They were also evaluated under these same circumstances with a hearing aid that reduces low frequencies and extends the high frequencies to nearly 6 500 Hz. Results indicate that these patients performed better and perferred the hearing aid that extends the high and reduces the low frequencies, particularly in noisy places. As a group, they did not prefer this type of amplification in quite listening situations.

Aged↗