Management of hearing loss in infants: the UTD/Callier Center position statement.

As infants are being identified earlier and earlier by universal newborn hearing screening programs, there is a need to establish principles for professionals involved in habilitative processes. Recently, a panel of experts was convened for a 2-day conference entitled "Habilitative Issues for Infants with Hearing Loss," the Bruton Conference on Audiology/Communication Sciences, UTD/Callier Center for Communication Disorders. The purpose of this document was to summarize the panel's discussions on habilitative principles, state-of-the-art practices, and future needs for infants with hearing loss.

Hearing and ultrasound-assisted liposuction: the effect on surgeon and patient.

Ultrasound-assisted liposuction has become an important tool in body-contouring surgery. Although ultrasound frequency is by definition outside the range of normal human hearing, an audible sound is heard during ultrasound-assisted liposuction. This study measured sound intensity during ultrasound-assisted liposuction performed with two commercially available systems. Sound intensity was measured at the surgeon's ear, surgical site, and patient's glabella. All measurements obtained with both machines fell within acceptable standards as defined by the Occupational Safety and Health Administration. Use of ultrasound-assisted liposuction does not pose a risk to the patient, the surgeon, or operating room personnel.

Physiology, pathophysiology, and anthropology/epidemiology of human earcanal secretions.

Two types of glands are found in the outer third of the human earcanal: sebaceous glands that produce sebum and modified apocrine glands that produce apocrine sweat. Together, these substances make up cerumen, which serves to clean, lubricate, and, to some extent, protect the earcanal from bacteria and fungus. Excessive/impacted cerumen can cause tinnitus, vertigo, itching, pain, external otitis, and hearing loss. Two populations are known to have a high incidence of excessive/impacted cerumen: individuals with mental retardation and the elderly. Anthropologists have used cerumen type to tract human migratory patterns and epidemiologists have related cerumen type to breast cancer.

Cerumen management: professional issues and techniques.

Cerumen management is now within the scope of practice for audiologists. This paper describes the knowledge and skills required to perform cerumen management safely and effectively. Procedures for mechanical removal, suction, and irrigation are provided.

Incidence of excessive/impacted cerumen in individuals with mental retardation: a longitudinal investigation.

A major sequelae of impacted cerumen (earwax) is conductive hearing loss, which can be deleterious to linguistic, social, and intellectual development, particularly for individuals with mental retardation. The longitudinal incidence (12-year period) of excessive/impacted cerumen and related conductive hearing loss of 117 adults with mental retardation was examined. Results indicated a considerably higher incidence of excessive cerumen and cerumen impaction with associated conductive hearing loss in adults with mental retardation (28%) than in the general adult population (2% to 6%). Moreover, a strong propensity for recurrent cerumen impaction in the mentally retarded population was found. These findings were discussed in view of the management of cerumen impaction among individuals with mental retardation.

Callier Center for Communication Disorders, University of Texas at Dallas.

The Callier Center offers a wide variety of services for those with communication disorders, as well as programs for research and academic training. Bringing together clinical and research specialists from a variety of related disciplines, Callier affords an unusual opportunity for interdisciplinary clinical programs, research, and enriched student training.

What Audiologists Must Know About Cerumen and Cerumen Management.

The Legislative Council of the American Speech-Language-Hearing Association recently accepted several scope of practice statements, including one concerned with external auditory canal examination and cerumen management by audiologists (Asha, 1992). Now that cerumen management is encompassed within the scope of practice of audiology, audiologists must know about cerumen-its physiology and pathophysiology, its effect on the practice of audiology, and its management. The purpose of this paper is to review the physiology and pathophysiology of cerumen production and to describe a procedure proven safe and effective for managing cerumen.

Three studies comparing performance of the ER-3A tubephone with the TDH-50P earphone.

Three studies compared the performance of the ER-3A Tubephone insert earphone and the TDH-50P-MX41/AR supra-aural earphone. The three factors addressed were: threshold differences in children 7 to 10 yr old compared to adults, differences in real ear attenuation, and threshold differences in the presence of high background noise levels. The influence of insertion depth of the ER-3A Tubephone was also investigated. Findings showed no significant threshold differences between children and adults, significantly better real ear attenuation for the ER-3A Tubephone, and significantly better thresholds for the ER-3A in the presence of high background noise levels. Most critically, there was a significant change in attenuation characteristics of the ER-3A Tubephone, which was dependent on the insertion depth of the ear-tip.

Ultrasonic lithotripsy: the risk of hearing loss.

Ultrasonic lithotripsy has been applied widely to the percutaneous removal of upper tract calculi. The high noise levels generated by ultrasonic lithotriptors during clinical use have raised some concern among endourologists. In this study sound level measurements of all 3 commercially available ultrasonic lithotriptors were obtained in the audiology laboratory and operating room. In all circumstances the maximum noise levels recorded (103 dBA. or less) for the time of exposure that would be encountered in the clinical setting of ultrasonic lithotripsy never exceeded safe levels. We concluded that the routine use of ultrasonic lithotriptors does not present a hazard to the hearing of normal individuals.

Dichotic consonant-vowel (CV) perception in normal and learning-impaired children.

Two experiments were performed using dichotic presentation of the consonant-vowel (CV) syllables [pa], [ba], [ta], [da], [ka], and [ga]. The stimuli were constructed with no temporal offsets between channels (+/-2 msec) and with temporal offsets of 30, 60, and 90 msec between channels. Data were analyzed for ear asymmetry (right ear advantage), double-correct responses (auditory capacity), and the effects of temporal offsets (the lag effect). In experiment 1, 32 normal children (mean age at entry = 6 yrs 6 mos) were evaluated once each year over a 4-yr period. Results showed no significant change in ear laterality over the 4 yrs. However, there was a significant, age-related increase in auditory capacity. None of the subject groups showed a significant lag effect. In experiment 2 results from 17 children (mean age = 9.3 yrs) enrolled in a school for learning disability who were identified as having significant auditory processing problems were compared to age- and sex-matched normal controls. Results failed to show a significant group difference for ear asymmetry, auditory capacity, or the lag effect. Case studies are presented comparing two learning-disabled children with two normal children matched for age and sex to illustrate the results for the learning-impaired population. Overall, findings indicate that the dichotic CV syllables test has limited prognostic value in identifying auditory processing dysfunction in children classified as having "learning disability."

Implementing an industrial hearing conservation program in the schools.

The harmful effects of exposure to high noise levels have been well-documented and include auditory and non-auditory factors. The most notable auditory effect is permanent loss of hearing, many times accompanied by the constant perception of a ringing-type noise in the ears (tinnitus). Despite this, there has been insufficient attention given to the hazardous effects of noise in the school health education curriculum. The industrial arts program is one area that deserves special attention because of the noise levels that teachers and students are exposed to in the classroom and the assumed future exposure that students will experience in their recreational and work experiences. This report describes a hearing conservation program implemented in the Industrial Arts Program in the Dallas Independent School District that attempts to provide: 1) protection for students and teachers using equipment that produces excessive, damaging noise; and 2) information to students on the hazardous effects of noise, so they will understand the consequences of not protecting their ears when exposed to excessive noise and the available means to protect their hearing. As the cost of the program was minimal, other school districts could implement similar programs with little additional resources and effort.

Evaluating changes in the communication skills of deaf children using vibrotactile stimulation.

Results of a 9-mo longitudinal study designed to evaluate the efficacy of a vibrotactile aid, the SRA-10, with four profoundly deaf preschool children are reported. During the study the subjects were enrolled in 30-min triweekly language therapy sessions, and changes in communication skills in connected discourse (vocalization only, sign language only, and vocalization plus sign language) were measured using a computer-based observation system. Changes in structural and semantic aspects of language were also measured. The four subjects were evaluated during one 16-week phase in which the aid was used (aid-on condition) and another 8 weeks in duration in which the aid was not used (aid-off condition). Communication skills improved in the aid-on condition and decreased in the aid-off condition. The changes were found to be significant for the communication involving the vocalization plus sign language (Total Communication) measure, indicating that the vibrotactile stimulation was positively associated with the communicative act.

A modified polymer foam earplug for the hearing aid evaluation.

Functional gain was compared with 12 subjects using three earmold conditions: an E-A-R polymer foam earplug modified for use with a hearing aid, a personal custom earmold, and a best-fit receiver-type stock earmold. Functional gain was equivalent between the modified E-A-R earplug and the custom earmold conditions. The stock earmold condition resulted in a significant shunting of low-frequency amplification. The gain control of the personal hearing aids could be adjusted to the user comfort level gain setting without resulting in acoustic feedback in only the modified E-A-R earplug and custom earmold conditions. These findings are discussed relative to the hearing aid evaluation.

Clinical experience with tinnitus maskers.

Results from tinnitus evaluations and follow-up questionnaires were used in an effort to assess the efficacy of tinnitus masking units as a means of providing active and/or passive relief for patients experiencing problematical tinnitus. Nine of 34 patients (26%) who were felt to be candidates for masking units reported that they were receiving some form of relief from their tinnitus.

Ototoxicity in neonates treated with gentamicin and kanamycin: results of a four-year controlled follow-up study.

This article reports the results of a four-year follow-up study initiated in 1970 on the long-term effects of gentamicin and kanamycin use in newborn infants. Audiometric, vestibular, and psychometric evaluations were performed on gentamicin-treated, kanamycin-treated, and untreated, matched control infants and children. No substantial sensorineural hearing loss or vestibular dysfunction was identified in these patients that could be attributed to aminoglycoside therapy. Performances on the Illinois Test of Psycholinguistic Abilities, Beery Test of Visual Motor Integration, the Peabody Picture Vocabulary Test, and on fine and gross motor examinations were comparable for the three study groups.