F. Erwin Offeciers
University of Antwerp
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Otology & Neurotology | 2002
Paul J. Govaerts; Carina De Beukelaer; Kristin Daemers; Geert De Ceulaer; Marjan Yperman; Thomas Somers; Isabelle Schatteman; F. Erwin Offeciers
Objective To evaluate the outcome of cochlear implantation in young children in relation to the age at implantation. Study Design A retrospective longitudinal and cross-sectional analysis of pediatric cochlear implant patients. Patients All children with congenital deafness who underwent implantation before the age of 6 years (n = 48 for the longitudinal analysis and n = 70 for the cross-sectional analysis) Interventions All children received a multichannel cochlear implant. Main Outcome Measures Categories of Auditory Performance (CAP) score and integration into the mainstream school system. Results For all children, the CAP score increased after implantation. Implantation beyond the age of 4 years hardly ever resulted in normal CAP scores or in integration into the mainstream primary school (20 to 30% of cases). Implantation between the age of 2 and 4 years always resulted in normal CAP scores after 3 years with a 66% probability of integration into the primary school. Implantation before the age of 2 years always resulted in immediate normalization of the CAP scores, with a 90% probability of integration into the mainstream kindergarten, well before entrance into the primary school. Conclusion All children with congenital deafness who underwent implantation before the age of 6 years appeared to benefit from the implant. However, these data add evidence to the importance of early implantation (before the age of 2 years). Intervention before the age of 4 years seemed to be critical to avoid irreversible auditory performance losses, and intervention before the age of 2 years seemed to be critical to achieve optimal results.
Audiology and Neuro-otology | 2010
Lieselot Van Deun; Astrid Van Wieringen; Fanny Scherf; Naima Deggouj; Christian Desloovere; F. Erwin Offeciers; Paul Van de Heyning; Ingeborg Dhooge; Jan Wouters
We present sound localization results from 30 children with bilateral cochlear implants. All children received their implants sequentially, at ages from 6 months to 9 years for the first implant and 1.5–12 years for the second implant, with delays of 10 months to 9 years. Localization was measured in the sound field, with a broadband bell-ring presented from 1 of 9 loudspeakers positioned in the frontal horizontal plane. The majority of the children (63%) were able to localize this signal significantly better than chance level. Mean absolute error scores varied from 9 to 51° (root mean square error scores from 13 to 63°). The best scores were obtained by children who received their first implant before the age of 2 years and by children who used hearing aids prior to implantation for a period of 18 months or longer. Age at second implantation was important in the group of children who did not use a contralateral hearing aid during the unilateral implant period. Additionally, children who attended a mainstream school had significantly better localization scores than children who attended a school for the deaf. No other child or implantation variables were related to localization performance. Data of parent questionnaires derived from the Speech, Spatial and Qualities of Hearing Scale were significantly correlated with localization performance. This study shows that the sound localization ability of children with bilateral cochlear implants varies across subjects, from near-normal to chance performance, and that stimulation early in life, acoustically or electrically, is important for the development of this capacity.
American Journal of Human Genetics | 2001
Kris Van Den Bogaert; Paul J. Govaerts; Isabelle Schatteman; Matthew R. Brown; Goele Caethoven; F. Erwin Offeciers; Thomas Somers; Frank Declau; Paul Coucke; Paul Van de Heyning; Richard J.H. Smith; Guy Van Camp
Otosclerosis due to abnormal bone homeostasis of the otic capsule is a frequent cause of hearing loss in adults. Usually, the hearing loss is conductive, resulting from fixation of the stapedial footplate, which prevents normal ossicular vibration in response to sound. An additional type of sensorineural hearing loss may be caused by otosclerotic damage to the cochlea. The etiology of the disease is unknown, and both environmental and genetic factors have been implicated. Autosomal dominant inheritance with reduced penetrance has been proposed, but large families are extremely rare. To elucidate the pathogenesis of the disease, identification of the responsible genes is essential. In this study, we completed linkage analysis in a Belgian family in which otosclerosis segregates as an autosomal dominant disease. After excluding linkage to a known locus on chromosome 15 (OTSC1), we found linkage on chromosome 7q, with a multipoint LOD score of 3.54. Analysis of key recombinant individuals maps this otosclerosis locus (OTSC2) to a 16-cM interval on chromosome 7q34-36 between markers D7S495 and D7S2426.
Ear and Hearing | 2009
Lieselot Van Deun; Astrid Van Wieringen; Tim Van den Bogaert; Fanny Scherf; F. Erwin Offeciers; Paul Van de Heyning; Christian Desloovere; Ingeborg Dhooge; Naima Deggouj; Leo De Raeve; Jan Wouters
Objectives: In this study, procedures for measuring sound localization, sound lateralization, and binaural masking level differences (BMLDs) in young children were developed. Sensitivity for these tasks was assessed in large groups of children between 4 and 9 yr of age to investigate potential developmental trends. Design: Sound localization was measured in the sound field, with a broadband bell-ring presented from one of nine loudspeakers positioned in the frontal horizontal field. A group of 33 children between 4 and 6 yr of age and 5 adults took part in this experiment. Sound lateralization based on interaural time differences was measured with headphones in 49 children between 4 and 9 yr of age and 10 adults. A low-frequency stimulus containing harmonics 2 to 5 from a click train with a rate of 160 Hz was used. In the BMLD test, the same filtered click train was presented diotically or dichotically (phase reversed or time delayed) in a broadband (200 to 1000 Hz) frozen noise to 23 children between 4 and 6 yr of age and 10 adults. For comparison with literature, additional measurements with a 500-Hz sinusoid were administered to adults. All tasks were adapted to the interest and attention span of young children. Results: Children of 5 yr of age did not perform significantly different from adults on the sound localization task, but mean absolute errors were larger for the 4-yr-olds. Also on the BMLD task, 5-yr-old children performed at the adult level, whereas the 4-yr-old children obtained significantly less binaural unmasking compared with the adults. Concerning sound lateralization, a small but significant difference between adults and children existed, but no age effects were apparent in the 4- to 9-yr-old group. Overall, the variation was relatively large in the 4-yr-old group, with some of the children performing at adult level, in all three tasks. Conclusions: The results of this study show that the modified procedures are suitable for testing children from the age of 4 to 5 yr. Furthermore, it seems that binaural hearing capacities of the 5-yr-olds are similar to those of adults. Several observations led to the hypothesis that the observed age differences between 4-yr-olds and older subjects on localization and BMLD or between those 4- to 9-yr old and adults on lateralization, were attributable to both a development in binaural hearing and to nonauditory factors, such as task comprehension, attention, and testing conditions. It is possible that the developmental process is more obvious and prolonged in other aspects of binaural hearing, which require more dynamic or more central processing.
Otology & Neurotology | 2001
Geert De Ceulaer; Marjan Yperman; Kristin Daemers; Kristin Van Driessche; Thomas Somers; F. Erwin Offeciers; Paul J. Govaerts
Hypothesis Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) can be used in a clinical set-up using a procedure based on a unique and robust parameter to quantify the magnitude of suppression for a subject. Background TEOAEs can be suppressed by delivering contralateral white noise (WN). This suppression is thought to be mediated via the efferent nerve fibers that innervate the outer hair cells. The ipsilateral TEOAE-eliciting click stimulus level and the contralateral WN level have a strong impact on the recorded level of suppression. Methods TEOAEs were recorded using the nonlinear stimulation mode in two conditions (with and without contralateral WN). An optimal TEOAE-eliciting click stimulus level and contralateral WN level were defined to obtain a unique and robust parameter to quantify the magnitude of suppression. Results Suppression of TEOAEs with contralateral WN can be measured in a clinical set-up using nonlinear stimulation, and the level of suppression is of the same order of magnitude as measures using the linear stimulation recording mode. The level of suppression appears to be “locked” to the interaural difference between ipsilateral TEOAE-eliciting broadband click stimulus level and the contralateral WN level. Conclusions A procedure is proposed to record contralateral suppression in a clinical set-up, and normative data are given for a normal-hearing population (n = 60).
Audiology and Neuro-otology | 2009
Lieselot Van Deun; Astrid Van Wieringen; Tom Francart; Fanny Scherf; Ingeborg Dhooge; Naima Deggouj; Christian Desloovere; Paul Van de Heyning; F. Erwin Offeciers; Leo De Raeve; Jan Wouters
Bilateral cochlear implants (CIs) may offer deaf children a range of advantages compared to unilateral CIs. However, speech perception in noise is mainly facilitated by better-ear effects and much less by interaural comparisons or true ‘binaural’ hearing. Little is known about the development of the binaural auditory system with CIs provided at a young age. It is possible that, as with adults, binaural sensitivity exists but is not accessed due to technical limitations in electrical stimulation methods. In this paper, we present results on binaural hearing in children with bilateral CIs. Binaural masking level differences (BMLDs) were measured for a 180-degree phase shift in a 125-Hz sinusoid, presented in a 50-Hz-wide noise band and modulating a 1000-pps carrier pulse train. Stimuli were presented to a single electrode in the middle of the electrode array at both ears. Eight children between 6 and 15 years of age participated in this study. Six children had a significantly better detection threshold when the signal was out of phase (dichotic) between two ears than when it was in phase (diotic), with a mean difference (BMLD) of 6.4 dB. The present results show that children with bilateral CIs are sensitive to binaural cues in electrical stimuli, similar to adults, even when implants are provided at a later age and with a longer delay between implantations.
Annals of Otology, Rhinology, and Laryngology | 1993
Paul J. Govaerts; Thérèse Marquet; W. R. J. Cremers; F. Erwin Offeciers
Because of the important function of the embryologic stapedial artery, it is taken for granted by many surgeons that the finding of such a persistent artery in postnatal humans during middle ear surgery should urge maximal caution in order not to damage the artery. Often, discontinuation of the surgery is recommended. Yet this attitude is based on theoretic considerations rather than on any clinical evidence of complications following injury to this vessel. The present paper describes the embryology in relation to this specific aspect and reviews the literature on the persistent stapedial artery, emphasizing the papers dealing with injury to this vessel. In addition, we report 4 cases of persistent stapedial artery from the files of almost 20,000 patients in whom tympanotomy was performed. From all these data we conclude that injury to this artery or even complete section probably does not cause major, if any, postoperative sequelae, and that consequently, middle ear surgery is not necessarily hindered by the presence of this vessel.
Otology & Neurotology | 2001
Paul J. Govaerts; Marjan Yperman; Geert De Ceulaer; Kristin Daemers; Kristin Van Driessche; Thomas Somers; F. Erwin Offeciers
Objective A model is proposed for universal neonatal hearing screening. Methods The screening model is two-staged because it consists of a first test and, in case of failure (1.4% of the subjects), of a retest 3 weeks later. It is bipodal because it involves both the hospital audiologic department and a central Well Baby Organization. The idea is to have a maximal number of newborns tested at the maternity by trained audiologists and to have the Well Baby Organization trace and chase the missing subjects. The model has been evaluated during 1 calendar year (1999) in a maternity with 2,012 newborns. Result The result is a coverage of 99.3%. Most newborns (97.3%) were tested at the maternity ward with a total time investment of less than 15 minutes per child. The actual test time is 2 minutes, 12 seconds (median value). The Well Baby Organization keeps track of all the results and has to test no more than 2% of the newborns. Sensitivity and specificity were not the primary outcomes of this evaluation, but they were similar to those of a previous study evaluating the screen procedure on a larger scale, giving a sensitivity of approximately 100% and a false alarm rate of 1/1,000. Conclusion These figures demonstrate that universal neonatal hearing screening is feasible within the existing health care structure, with unprecedented coverage, sensitivity, and specificity.
Otolaryngology-Head and Neck Surgery | 1998
Paul J. Govaerts; Thomas Somers; F. Erwin Offeciers
The Committee on Hearing and Equilibrium of the American Academy of Otolaryngology—Head and Neck Surgery has published guidelines for the reporting of audiometric results of middle ear interventions. It recommends the reporting of several audiometric variables by means of two summary parameters: means and standard deviation. This article advocates the use of other summary statistics, namely the median, quartiles, and extremes, because they do not require a normal distribution of the audiometric data and they are not sensitive to variations of the extreme values. On the basis of the exploratory data analysis, we propose a graphic method to present the Committees variables in terms of their summary statistics. This “multiple box and whisker plot” offers a detailed and accurate overview of six variables in one graph. (Otolaryngol Head Neck Surg 1998;118:892–5.)
Annals of Otology, Rhinology, and Laryngology | 1996
Evert P. P. M. Hamans; Thomas Somers; Paul J. Govaerts; F. Erwin Offeciers
Seventy allograft type 1 tympanoplasties in children under 16 years of age were studied retrospectively. Only patients with a tympanic membrane perforation without cholesteatoma and a normal ossicular chain were included. Short-term and long-term anatomic and functional results were analyzed after a mean follow-up of 40 months. The overall short-term take rate was 97% and the long-term take rate was 88%. A number of variables with alleged prognostic value for surgical outcome were analyzed, but none showed statistical correlation with either anatomic or functional results. A median hearing gain of 10 dB was achieved, which was stable over time. We conclude that allograft tympanoplasty type 1 in this group of children is anatomically and functionally successful regardless of age.