Vestibular Infant Screening (VIS)–Flanders : results after 1.5 years of vestibular screening in hearing-impaired children

Due to the close anatomical relationship between the auditory and vestibular end organs, hearing-impaired children have a higher risk for vestibular dysfunction, which can affect their (motor) development. Unfortunately, vestibular dysfunction often goes unnoticed, as vestibular assessment in these children is not standard of care nowadays. To timely detect vestibular dysfunction, the Vestibular Infant Screening–Flanders (VIS–Flanders) project has implemented a basic vestibular screening test for hearing-impaired infants in Flanders (Belgium) with a participation rate of 86.7% during the first year and a half. The cervical Vestibular Evoked Myogenic Potentials (cVEMP) test was applied as vestibular screening tool to map the occurrence of vestibular (mainly saccular) dysfunction in this population. At the age of 6 months, 184 infants were screened. No refers on vestibular screening were observed in infants with permanent conductive hearing loss. In infants with permanent sensorineural hearing loss, a cVEMP refer rate of 9.5% was observed. Failure was significantly more common in infants with severe-profound compared to those with mild-moderate sensorineural hearing loss (risk ratio = 9.8). Since this is the first regional study with a large sample size and successful participation rate, the VIS–Flanders project aims to set an example for other regions worldwide

Le bilan multidisciplinaire des enfants de 18 à 36 mois en difficulté langagière

Détecter très précocement les enfants qui risquent de présenter un trouble du langage et/ou de la communication est d’une importance capitale pour agir au plus vite et éviter ainsi une aggravation de la situation. Mais comment agir, sur quoi se baser pour poser un diagnostic tant soit peu fiable ? Comment se positionner entre un attentisme parfois euphorique et un activisme peut-être hâtif ? Sans minimiser les risques d’une éventuelle pathologie ou les épingler sans fondement, un juste milieu appelle une prudence active, réfléchie, basée sur des indices objectifs à relativiser. Tel est l’objet de ce livre. Un bilan très complet qui envisage l’enfant sous les aspects O.R.L., logopédique, psychomoteur, cognitif, affectif, neuropédiatrique et enfin génétique. Un bel exemple d’une collaboration et d’une synthèse harmonieuses réalisées par l’Equipe du Centre Universitaire d’Audiophonologie, les Services de Neuropédiatrie et de Génétique des Cliniques Saint-Luc (U.C.L.). Sont présentées des Echelles de développement des compétences communicationnelles et langagières précoces, récemment élaborées et étalonnées. L’une d’elles fait partie intégrante de la liste limitative des tests reconnus par l’INAMI

Imaging and cochlear implant.

The auditory pathway imaging may be morphologic and/or functional. The high resolution computed tomography and the magnetic resonance imaging (MRI) provide an evaluation of the anatomical and structural landmarks useful for a safe and successful cochlear implantation. The electrical stimulations supplied by the cochlear implant give rise to ascending electrochemical activities reaching the cortex. These activities can be recorded with scalp electrodes by Evoked Potentials (EP) or fields techniques and eventually translated in isochronic or isopotential brain mapping. These techniques provide a very sharp temporal resolution with an imprecise spatial resolution. The late auditory EP of implantees are closely comparable to the responses of normal hearing people. The neuronal metabolism's increase is associated with a cerebral blood flow increase. Comparing regional cerebral blood flow (rCBF) between two or more conditions allows the localisation of brain areas involved in a fixed task. Single photon or positron emission tomography and functional MRI (fMRI) demonstrate cBF changes associated with an auditory stimulation. (f)MRI is contraindicated in cochlear implantees

Les aides auditives implantables.

The purpose of these hearing aids is to improve the quantity and quality of amplification of the sound wave. Their operating principle is based on the existence of a transducer which transforms the electric signal captured by the microphone into a mechanical, vibrating wave. This transducer can act either directly on the temporal bone by short-circuiting the middle ear (and is then called a bone conduction implant) or directly on the ossicular chain (in which case it is called an ossicular transduction implant). A) There are 2 types of bone conduction implant: the "Audiant Bone Conduction" system of Hough-Vernon (Xomed), where an outside electromagnetic coil sends signals transcutaneously to a magnetic screw embedded on the temporal bone. Bone conduction must be normal. The "Bone Anchored Hearing Aid" (Nobelpharma) where the outside electromagnetic coil sends signals directly to the magnetic screw that is percutaneous. The mean thresholds in bone conduction can reach up to 45 dB. The drawbacks of this system lie in its inaesthetic appearance and the risk of infection. B) With ossicular transduction implants, the transducer may be: either an electromagnetic coil influencing a magnet fixed to the tympanum, on the ossicular chain, or replacing an element of the ossicular chain (these hearing aids are marketed by Richards); or a piezo-electric crystal which produces vibrations when it is subjected to an AC current, and which can be positioned on the stapes (Yanagihara). This system consumes less energy, gives excellent results for the high frequencies, but is more cumbersome