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Biomedical subjects

S M Mason

Publications and source records attributed to S M Mason.

45 records · Page 3Linked to original sources
PubMed1981

Simultaneous recording of extra-tympanic electrocochleography and brainstem evoked responses in clinical practice.

Normal and clinical cases were investigated with simultaneous recording of extra tympanic electrocochleography and brainstem evoked responses. In group 3 cases where a non-recruiting hearing loss greater than or equal to 40 db. at 2 KHz and/or 4 KHz is present, brainstem recordings alone are not adequate for differential diagnosis of deafness due to the frequent inability to identify wave I. Therefore, electrocochleography is essential in these cases for determining the N1-V interpeak latency. Ideally cases as characterized in group 3 should be investigated by simultaneous recording of the brainstem evoked response and electrocochleography, preferably by a non-invasive technique. The test procedure is acceptable as a routine clinical investigation and avoids delay in diagnosis.

Action Potentials↗
PubMed1981

Glycerol dehydration tests in Ménière's disorder using extratympanic electrocochleography.

Eleven patients with classical Ménière's disorder were examined electrophysiologically using extratympanic electrocochleography. All had been fully investigated audiologically and by electronystagmography. In addition to the classical triad of symptoms, 7 complained also of fullness or blockage in the ear, this symptoms being associated with fluctuation of the deafness. All patients showed the characteristic enhancement of the SP component of the AP/SP waveform. Following glycerol the SP component was reduced in amplitude, producing a decrease in the width of the waveform. Maximum reduction occurred approximately 60 min after administration of glycerol.

Cochlear Microphonic Potentials↗
PubMedDate not supplied

Prolongation of the cochlear microphonic in man. Cochlear microphonic ringing.

During routine extra-tympanic electrocochleographic (ECochG) recording we have observed that in many cases more cycles are seen in the cochlear microphonic (CM) recording than are present in the acoustic stimulus. We have termed this phenomenon CM 'ringing'. Ringing is present in 69% of our normal subjects and in 43% of patients with deafness of different aetiologies. In the cochlear and Ménière subgroups those cases showing ringing have a significantly larger CM amplitude (p less than 0.001 and p less than 0.01 respectively). The possible origin of this phenomenon is discussed.

Audiometry↗