42 research outputs found
Electrical vestibular stimulation in humans: a narrative review
Background: In patients with bilateral vestibulopathy, the
regular treatment options, such as medication, surgery, and/
or vestibular rehabilitation, do not always suffice. Therefore,
the focus in this field of vestibular research shifted to electrical vestibular stimulation (EVS) and the development of a
system capable of artificially restoring the vestibular function. Key Message: Currently, three approaches are being
investigated: vestibular co-stimulation with a cochlear implant (CI), EVS with a vestibular implant (VI), and galvanic
vestibular stimulation (GVS). All three applications show
promising results but due to conceptual differences and the
experimental state, a consensus on which application is the
most ideal for which type of patient is still missing. Summary: Vestibular co-stimulation with a CI is based on “spread of
excitation,” which is a phenomenon that occurs when the
currents from the CI spread to the surrounding structures
and stimulate them. It has been shown that CI activation can
indeed result in stimulation of the vestibular structures.
Therefore, the question was raised whether vestibular costimulation can be functionally used in patients with bilateral vestibulopathy. A more direct vestibular stimulation
method can be accomplished by implantation and activation of a VI. The concept of the VI is based on the technology
and principles of the CI. Different VI prototypes are currently
being evaluated regarding feasibility and functionality. So
far, all of them were capable of activating different types of
vestibular reflexes. A third stimulation method is GVS, which
requires the use of surface electrodes instead of an implanted electrode array. However, as the currents are sent through
the skull from one mastoid to the other, GVS is rather unspecific. It should be mentioned though, that the reported
spread of excitation in both CI and VI use also seems to induce a more unspecific stimulation. Although all three applications of EVS were shown to be effective, it has yet to be
defined which option is more desirable based on applicability and efficiency. It is possible and even likely that there is a
place for all three approaches, given the diversity of the patient population who serves to gain from such technologies
Pediatric cochlear implantation: an update
Deafness in pediatric age can adversely impact language acquisition as well as educational and social-emotional
development. Once diagnosed, hearing loss should be rehabilitated early; the goal is to provide the child with
maximum access to the acoustic features of speech within a listening range that is safe and comfortable. In presence
of severe to profound deafness, benefit from auditory amplification cannot be enough to allow a proper language
development. Cochlear implants are partially implantable electronic devices designed to provide profoundly deafened
patients with hearing sensitivity within the speech range. Since their introduction more than 30 years ago, cochlear
implants have improved their performance to the extent that are now considered to be standard of care in the
treatment of children with severe to profound deafness. Over the years patient candidacy has been expanded and
the criteria for implantation continue to evolve within the paediatric population. The minimum age for implantation
has progressively reduced; it has been recognized that implantation at a very early age (12–18 months) provides
children with the best outcomes, taking advantage of sensitive periods of auditory development. Bilateral implantation
offers a better sound localization, as well as a superior ability to understand speech in noisy environments than unilateral
cochlear implant. Deafened children with special clinical situations, including inner ear malformation, cochlear nerve
deficiency, cochlear ossification, and additional disabilities can be successfully treated, even thogh they require
an individualized candidacy evaluation and a complex post-implantation rehabilitation. Benefits from cochlear
implantation include not only better abilities to hear and to develop speech and language skills, but also improved
academic attainment, improved quality of life, and better employment status. Cochlear implants permit deaf people
to hear, but they have a long way to go before their performance being comparable to that of the intact human ear;
researchers are looking for more sophisticated speech processing strategies as well as a more efficient coupling
between the electrodes and the cochlear nerve with the goal of dramatically improving the quality of sound of
the next generation of implants
Decision aid prototype development for parents considering adenotonsillectomy for their children with sleep disordered breathing
Development of Sensory, Motor and Behavioral Deficits in the Murine Model of Sanfilippo Syndrome Type B
BACKGROUND: Mucopolysaccharidosis (MPS) IIIB (Sanfilippo Syndrome type B) is caused by a deficiency in the lysosomal enzyme N-acetyl-glucosaminidase (Naglu). Children with MPS IIIB develop disturbances of sleep, activity levels, coordination, vision, hearing, and mental functioning culminating in early death. The murine model of MPS IIIB demonstrates lysosomal distention in multiple tissues, a shortened life span, and behavioral changes. PRINCIPAL FINDINGS: To more thoroughly assess MPS IIIB in mice, alterations in circadian rhythm, activity level, motor function, vision, and hearing were tested. The suprachiasmatic nucleus (SCN) developed pathologic changes and locomotor analysis showed that MPS IIIB mice start their daily activity later and have a lower proportion of activity during the night than wild-type controls. Rotarod assessment of motor function revealed a progressive inability to coordinate movement in a rocking paradigm. Purkinje cell counts were significantly reduced in the MPS IIIB animals compared to age matched controls. By electroretinography (ERG), MPS IIIB mice had a progressive decrease in the amplitude of the dark-adapted b-wave response. Corresponding pathology revealed shortening of the outer segments, thinning of the outer nuclear layer, and inclusions in the retinal pigmented epithelium. Auditory-evoked brainstem responses (ABR) demonstrated progressive hearing deficits consistent with the observed loss of hair cells in the inner ear and histologic abnormalities in the middle ear. CONCLUSIONS/SIGNIFICANCE: The mouse model of MPS IIIB has several quantifiable phenotypic alterations and is similar to the human disease. These physiologic and histologic changes provide insights into the progression of this disease and will serve as important parameters when evaluating various therapies