Biomedical subjects

R F Naunton

Publications and source records attributed to R F Naunton.

7 recordsLinked to original sources

PubMed1991

Successful treatment of selected cases of abductor spasmodic dysphonia using botulinum toxin injection.

Ten patients with abductor spasmodic dysphonia, who exhibited spasmodic bursts and heightened activity of the cricothyroid muscle during speech, were selected for participation. Between 5 and 20 U of botulinum toxin type A were injected into both right and left cricothyroid muscles. Six patients benefited substantially, whereas four did not. Acoustic analyses of voice patterns showed similar changes to the clinical impressions. Significant group improvements were found in sentence duration while selected patients improved in the proportion of their speech that was voiced and the duration of their voiceless consonants. Those patients with abductor spasmodic dysphonia and other muscle abnormalities in addition to the cricothyroid and with constant breathiness did not benefit.

Adult↗

PubMed1977

The evaluation of peripheral auditory function in infants and children.

The technique of electrocochleography described, although invasive, has proved to be innocuous in our experience. It provides precise information concerning peripheral auditory activity in response to sound stimulation at frequencies across the audible range. The most valuable application of the technique in clinical practice is in testing the hearing of infants and children who are too young to test by standard behavioral audiometric techniques, and in testing the hearing of children with behavioral problems or mental retardation;

Action Potentials↗

PubMed1976

Hereditary progressive sensorineural deafness.

Progressive sensorineural hearing losses found in seven members of three families are presented. Genetic transmission patterns in the study appeared to be autosomal dominant in two families and recessive in one family. The common audiological features of these cases include bilaterally symmetrical audiometric configuration and fairly good speech discrimination. The hearing losses of most of the cases appeared to begin at high frequencies progressing later to involve lower frequencies. The main histopathological changes in the temporal bones of one of the cases were degeneration of the organ of Corti and of the spiral ganglion in the lower cochlear coils and cystic degeneration of the stria vascularis in the upper coils.

Adult↗

PubMed1976

Basis and some diagnostic implications of electrocochleography.

Electrocochleography (ECoG) involves the recording of electrical responses to sound from the vicinity of the cochlea. The technique, as we practice it, utilizes a trans-tympanic recording needle situated on the promontory of the middle ear. Filtered clicks in the frequency range between 500 and 8,000 Hz are presented to the ear under test at a rate of 10/sec. Repetitive clicks of a given frequency are first presented at high intensity and the responses summed (averaged) in a computer. The click is systematically lowered in intensity, and an average is collected at each level until the normal dynamic range of hearing has been explored. Two major electrical indices are present in the recording: these are 1. the whole-nerve action potential (AP) derived from the first-order auditory neurons, and 2. the cochlear microphonic (CM) derived from the hair cells. Inspection of the whole nerve AP as intensity is lowered allows the estimation of the response threshold, which correlates well with behavioral threshold. Inspection of the relation between the CM and the AP allows qualitative differentiation to be made between pathology arising in the hair cell (sensory) and in the nerve (neural).

Acoustic Stimulation↗

PubMedDate not supplied

The Ear, Nose, and Throat Devices Classification Panel of the Food And Drug Administration.

The passage into law in 1976 of the Medical Device Amendments authorized the FDA to regulate the safety and efficacy of medical devices. The effects of this regulation are contrasted with the mode of entry of medical devices onto the market prior to 1976. The structure and operation of Ear, Nose, and Throat Devices Classification Panel is described briefly. Continued input from otolaryngologists and allied professionals is encouraged.

Legislation, Medical↗

PubMedDate not supplied

Physical and auditory specifications of third-octave clicks.

Physical: measurements of third-octave clicks (produced by ringing a commercial third-octave filter having a rejection rate of 50 dB in the first octave) show that waveform and spectral shape of the clicks remain the same through the range of audiometric frequencies. Auditory: relations between click and tonal thresholds are developed by (a) comparing click and tone thresholds at a repetition rate of 5/sec and (b) determining changes in click threshold for a range of repetition rates between 1 and 10/sec. Tonal thresholds are about 10 dB more sensitive at the 5/sec rate; a click repetition of 10/sec lowers the threshold, reducing the difference between tone and click audibility, while a repetition rate of 1/sec raises click threshold and increases the difference.

Acoustic Stimulation↗

PubMedDate not supplied

Human whole-nerve response to clicks of various frequency.

The averaged VIIIth nerve response to third-octave clicks at 500, 2000 and 8000 Hz was recorded from the promontory of 4 normal-hearing young adults. As click frequency is lowered, the N, latency increases in a manner consistent with the changes in velocity of the cochlear traveling wave. This finding suggests that clicks of different spectral content stimulate different regions of the basilar membrane. N amplitude shows a general increase with frequency; this observation appears related to the increased synchrony of neural firing that results from the higher velocity of the traveling wave in the more basal portions of the cochlea.

Acoustic Stimulation↗