Biomedical subjects

M L Bance

Publications and source records attributed to M L Bance.

4 recordsLinked to original sources

PubMed1998

Vestibular stimulation by multichannel cochlear implants.

The recipient of a Nucleus 22 multichannel cochlear implant began to experience severe vestibular stimulation related to the implant. This patient's experience initiated a study with the objective of determining the frequency of implant-related vestibulo-ocular stimulation. Subjects consisted of 17 randomly selected patients who use cochlear implants. Included in the study were 14 Nucleus 22 and three Med-El Combi 40-devices. Stimulation of the implants was performed both by individual channel and with sound field broad-band 80-dB noise using the users' normal device settings. Eye movements were monitored with infrared videonystagmography. Only one subject, who used a Med-El Combi 40, showed a consistent and strong ocular response to cochlear stimulation but had no subjective symptoms. The authors conclude that vestibulo-ocular activation is possible with multichannel cochlear implants but is infrequent and may not be clinically significant.

Cochlear Implants↗

PubMed1998

Vestibular disease unmasked by hyperventilation.

Hyperventilation-induced dizziness is often thought to be psychogenic, but its effects in the presence of known vestibular disease have not been adequately examined. In this study hyperventilation was tested in two models of vestibular disease. These were, first, patients with profound unilateral vestibular deficit (prior translabyrinthine acoustic neuroma resection [postsurgery group]) and, second, patients with variable unilateral vestibular deficit (unoperated unilateral acoustic neuroma [presurgery group]). Patients were hyperventilated for 90 seconds. Using infrared videonystagmography, 100% of the 32 postsurgery patients and 82% of the 28 presurgery patients developed nystagmus with hyperventilation. Hyperventilation was more sensitive than head shake for eliciting nystagmus in these models. The false-positive rate for nystagmus in 29 normal volunteers was 3.5% for hyperventilation and 10% for head shake. Our results show that hyperventilation can unmask underlying vestibular disease.

Dizziness↗

PubMed1994

Decision and cost analysis in acoustic neuroma diagnosis.

Demonstrating improved outcomes and cost containment are current health care imperatives. For many diseases, competing diagnostic tests are available. Each has a direct economic cost and indirect costs based on missed disease. It is often difficult to determine the most efficient testing strategy for a given patient. Clinical Decision Analysis can optimise diagnostic strategies to maximise cost-effectiveness. Analytic techniques are developed to allow analysis of diagnostic strategies that include multi-test protocols. The test parameters required for modelling these strategies are derived from a literature analysis.

Audiometry, Evoked Response↗

PubMed1993

Interaction of saccadic and vestibular mechanisms in combined eye-head gaze shifts.

Saccades are the only purely volitional eye movements available to primates. They are used extensively to acquire new or interesting targets in the visual environment. Most patients with saccadic disorders are referred to neurologists. Patients complaining of disorientation, however, are often presumed to be suffering from a vestibular disorder. Vestibular and saccadic physiology has been studied mostly in isolation of each other. We examine the interaction of saccadic burst neurons and vestibular signals to achieve accurate gaze shifts.

Animals↗