ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The entire series of auditory evoked responses has now been assessed for usefulness in electric response audiometry. At present, the slow waking cortical response is the method of choice for cooperative adult subjects. Brief-tone bursts as stimuli give excellent frequency specificity. The electrocochleogram, the frequency-following response, and the “middle” cortical responses have all been displaced by the brainstem responses (ABR). The latter are very useful for: (1) auditory screening of infants in intensive care units; (2) differential diagnosis of posterior fossa tumors; and (3) obtaining audiograms on young or otherwise difficult-to-test children. The latter application requires sedation, and frequency selectivity is only fair, but the early evaluation of young hearing-impaired children will be the most important future use of electric response audiometry.

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The general routine for recording the auditory brainstem responses (ABR) includes the use of earlobe electrodes as reference. Electrically linked electrodes on each side of the neck are almost indifferent with regard to the ABR, and such electrodes were used as reference in an analysis of the response patterns at the vertex and both earlobes. These contribute very significantly to conventional recordings, and it is preferable to use an indifferent electrode as reference for the active vertex electrode. If this measurement is supplemented with a differential recording between the 2 ear-lobes, the N, of the whole nerve action potential and other parts of the early ABR are easy to identify and the diagnostic possibilities in pathological cases will be improved.

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The calibration of the abrupt click stimulus used in auditory brainstem response audiometry presents some unique problems. This report describes the critical aspects of the click stimulus (intensity, waveform, polarity, and spectrum) and relates them to possible contamination of auditory brainstem response test results. Techniques for measuring and reporting click stimulus parameters are also discussed.

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The brainstem response to brief tones contains a large vertex-positive component. If high-pass filter settings above 20 Hz are used, particularly with high rolloff slopes, the morphology of the response changes so that a vertex-negative wave becomes the most prominent component of the response. The amplitude of the response is unaffected by stimulus presentation rates of up to 35/sec. Tones with longer rise times have greater frequency specificity, but at rise times of greater than 5 msec, the brainstem response becomes very small. At high intensities, regardless of the rise time, the response to tones is not completely frequency specific, and notched noise masking should be used to obtain frequency-specific responses.

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

Auditory brainstem response (ABR) results with 82 severely developmentally delayed infants and children suspected of being both deaf and blind are reported. Of the 79 children on whom acceptable ABR data were obtained, 34 or 43.0% had ABR thresholds in the normal-hearing range; 16 or 20.3% in the mild-to-moderate loss range; and 3 or 3.8% in the severe loss category. Twenty-six or 32.9% produced no ABR to clicks at a maximum intensity of 90 dB HL. On the basis of established audiological and neurological diagnostic criteria, 3 children showed neurological abnormality by ABR. We conclude that the hearing status of a high percentage of otherwise untestable children can be determined by ABR, that a significant number of infants and children who appear deaf are in fact not hearing impaired, and that the occurrence of brainstem neuropathology in this population is limited.

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID

ISSN:0196-0202    

出版商:OVID    

年代:1981

数据来源: OVID