Filiep J Vanpoucke

Cochlear Ltd · Cochlear Technology Centre

Speech audiometry tests are a crucial tool in clinical care and research. In Dutch, the common practice is to use lists of monosyllabic words with a consonant-vowel-consonant (CVC) structure. However, there are relatively few lists, and they are short. Here, the goal is to develop an adult speech audiometry test for Dutch (Flemish) consisting of ph...

Measurement of the complex electrical impedance of the electrode contacts can provide new insights into the factors playing a role in the preservation of residual hearing with cochlear implants (CIs). However, unraveling the contributions related to the different phenomena from impedance data necessitates more advanced measurement and analysis tech...

In the chapter, the authors address the prescient need to update accepted care models of cochlear implant (CI) fitting and long-term maintenance to better utilize self-care and tele-medicine possibilities, thus shifting the focus of CI maintenance to the recipient. There is a strong evidence base that such a move will better meet the needs of CI us...

Objectives: A clinically viable measure of listening effort is crucial in safeguarding the educational success of hard-of-hearing students enrolled in mainstream schools. To this end, a novel behavioral paradigm of listening effort targeting school-age children has been designed and reported in Hsu et al. (2017). The current article consists of tw...

Objectives: The data logs of Cochlear Nucleus cochlear implant (CI) sound processors show large interindividual variation in children's daily CI use and auditory environments. This study explored whether these differences are associated with differences in the receptive vocabulary of young implanted children. Design: Data of 52 prelingually deaf...

In the chapter, the authors address the prescient need to update accepted care models of cochlear implant (CI) fitting and long-term maintenance to better utilize self-care and tele-medicine possibilities, thus shifting the focus of CI maintenance to the recipient. There is a strong evidence base that such a move will better meet the needs of CI us...

Purpose: The introduction of connectivity technologies in hearing implants allows new ways to support cochlear implant (CI) users remotely. Some functionalities and services that are traditionally only available in an in-clinic care model can now also be accessed at home. This study explores the feasibility of a prototype of a tablet computer appl...

The Language ENvironment Analysis system (lena™) automatically analyzes the natural sound environments of children. Among other things, it estimates the amounts of adult words (awc), child vocalizations (cv), conversational turns (ct), and electronic media (tv) that a child is exposed to. To assess lena’s reliability, we compared it to manual trans...

Objectives: The newest Nucleus CI processor, the CP900, has two new options to improve speech-in-noise perception: (1) use of an adaptive directional microphone (SCAN mode) and (2) wireless connection to MiniMic1 and MiniMic2 wireless remote microphones. Design: An analysis was made of the absolute and relative benefits of these technologies in...

Purpose: We describe the natural auditory environment of people with cochlear implants (CIs), how it changes across the life span, and how it varies between individuals. Method: We performed a retrospective cross-sectional analysis of Cochlear Nucleus 6 CI sound-processor data logs. The logs were obtained from 1,501 people with CIs (ages 0-96 ye...

Objectives: A reliable and practical measure of listening effort is crucial in the aural rehabilitation of children with communication disorders. In this article, we propose a novel behavioral paradigm designed to measure listening effort in school-age children based on different depths and levels of verbal processing. The paradigm consists of a c...

This study aimed at evaluating the feasibility of an implanted microphone for cochlear implants (CI) by comparison of hearing outcomes, sound quality and patient satisfaction of a subcutaneous microphone to a standard external microphone of a behind-the-ear sound processor. In this prospective feasibility study with a within-subject repeated measur...

The number of cochlear implant (CI) users is increasing annually, resulting in an increase in the workload of implant centers in ongoing patient management and evaluation. Remote testing of speech recognition could be time-saving for both the implant centers as well as the patient. This study addresses two methodological challenges we encountered i...

Purpose: This article describes the perspectives of hearing device manufacturers regarding the exciting developments that the Internet makes possible. Specifically, it proposes to join forces toward interoperability and standardization of Internet and audiology. Method: A summary of why such a collaborative effort is required is provided from hi...

There is a wide range in performance for cochlear implant (CI) users and there is some evidence to suggest that implant fitting can be modified to improve performance if electrodes that do not provide distinct pitch information are de-activated. However, improvements in performance may not be the same for users of all CI devices; in particular for...

An exemplary method of minimizing an effect of channel interaction among a plurality of channels in a multi-channel cochlear implant system includes empirically generating an electrical spread matrix that is specific to a patient and representative of a channel interaction among a plurality of channels defined by a plurality of electrodes of electr...

Objectives: To investigate electrically evoked compound action potentials (eCAPs) measured with the neural response imaging (NRI) 'SmartNRI' algorithm. NRI thresholds and slopes were examined according to three aspects: (1) site along the cochlea, (2) development of responses over time, and (3) influence of age/duration of deafness. Methods: Thi...

Exemplary methods and systems of generating a graphical representation of an intracochlear trajectory of electrodes include using electrical field imaging to generate an electrical field spread curve for each of a plurality of electrodes contained within an electrode array at least partially inserted within a cochlear implant patient and generating...

Conclusion: Even with six defective contacts, spanning can largely restore speech perception with the HiRes 120 speech processing strategy to the level supported by an intact electrode array. Moreover, the sound quality is not degraded. Objectives: Previous studies have demonstrated reduced speech perception scores (SPS) with defective contacts...

Correct placement of the electrode is crucial for cochlear implantation (CI) surgery. It determines the access to the auditory nerve and subsequent hearing performance. Here, we propose an objective measures tool that can partially verify the electrode position. The intracochlear spread of the electrical fields is measured and analyzed by means of...

To determine how simultaneous dual-electrode stimulation (DES) can be optimized for the individual patient to deliver better sound quality and speech recognition. DES was compared with single-electrode stimulation (SES) with respect to the site of stimulation (X) in the cochlea, the spread of excitation (SOE), and channel interaction. Second, it wa...

Current steering between adjacent electrodes makes it possible to create more spectral channels than the number of electrodes in an electrode array. With current steering on nonadjacent electrodes, called "spanning," it could be possible to bridge a defective electrode contact or potentially reduce the number of electrode contacts for the same leve...

Tripolar and other electrode configurations that use simultaneous stimulation inside the cochlea have been tested to reduce channel interactions compared to the monopolar stimulation conventionally used in cochlear implant systems. However, these "focused" configurations require increased current levels to achieve sufficient loudness. In this study...

There are two modalities of dual electrode stimulation: a shifting, continuous excitation, which is the desired effect, and a split excitation with considerable variation in loudness. The first one most likely occurs in the basal turn, with adjacent contacts, stimulated simultaneously rather than sequentially. This study examines the effects on pla...

This is the first report on a successful cochlear implantation in a patient suffering from the Melnick-Needles syndrome (MNS). This case study presents an MNS patient with peri-lingual profound hearing loss, implanted at the age of 38. MNS is a rare X-linked genetic bony dysplasia characterized by skeletal and facial abnormalities. Various soft tis...

In this paper, we present an autonomous virtual mobile robot (AVMR) for three-dimensional (3D) exploration of unknown tubular-like structures in 3D images. The trajectory planning for 3D central navigation is achieved by combining two neuro-fuzzy controllers, and is based on 3D sensory information; a Hough transform is used to locally fit a cylinde...

To compare the effects of Monopole (Mono), Tripole (Tri), and "Virtual channel" (Vchan) electrode configurations on spectral resolution and speech perception in a crossover design. Nine experienced adults who received an Advanced Bionics CII/90K cochlear implant participated in a crossover design using three experimental strategies for 2 wk each. T...

Statistical shape modeling is widely used for medical image segmentation and interpretation. The main problem in building a shape model is the construction of a pointwise correspondence between the training objects. Manually corresponding objects is a subjective and time consuming task. Fortunately, surface parameterization can be automated and it...

X-ray microtomography (micro-CT) is a new technique allowing for visualization of the internal structure of opaque specimens with a quasi-histological quality. Among multiple potential applications, the use of this technique in otology is very promising. Micro-CT appears to be ideally suited for in vitro visualization of the inner ear tissues as we...

X-ray microtomography (micro-CT) is a new technique allowing for visualization of the internal structure of opaque specimens with a quasi-histological quality. Among multiple potential applications, the use of this technique in otology is very promising. Micro-CT appears to be ideally suited for in vitro visualization of the inner ear tissues as we...

SPAIDE (sound-processing algorithm integrated development environment) is a real-time platform of Advanced Bionics Corporation (Sylmar, Calif, USA) to facilitate advanced research on sound-processing and electrical-stimulation strategies with the Clarion CII and 90K implants. The platform is meant for testing in the laboratory. SPAIDE is conceptual...

Those suffering from a severe to profound sensorineural hearing loss can obtain substantial benefit from a cochlear implant prosthesis. An electrode array implanted in the inner ear stimulates auditory nerve fibers by direct injection of electrical current. A major limitation of today's technology is the imprecise control of intracochlear current f...

Electrical properties of the implanted scala tympani could be accurately modeled by means of a simple resistive ladder network model. The subject-specific model parameters can be obtained from electrical field imaging (EFI) recordings. It is a powerful tool for analysis of the cochlear current spread. In EFI mode, the telemetry systems of contempor...

We investigate the effects of IP channels on speech recognition systems and methods to recover the associated performance degradation. There are three major VoIP (voice over IP) distortion sources: speech encoding decoding (codecs), packet loss and jitter (time-delay). For speech recognition systems distortions are mainly from packet loss and the s...

Three baseline isolated word rejection strategies are initially proposed and their rejection performance is evaluated on two different types of out-of-vocabulary (OOV) utterances: OOV similar in nature to the in-vocabulary (IV) ones versus OOV consisting of non-speech events such as coughs, clicks, smacks, etc. A general OOV model, referred to as g...

Tracking the dominant subspace of a data matrix is an essential part of many signal processing algorithms. We present a modification to the so-called spherical subspace tracking algorithm. This algorithm has a low computational complexity, but suffers from accumulation of numerical errors. We show that this numerical instability can be circumvented...

A novel algorithm is presented for adaptive eigenfiltering and for updating the singular value decomposition (SVD). It is an improvement upon an earlier developed Jacobi-type SVD updating algorithm, where now the exact orthogonality of the matrix of singular vectors/eigenvectors is guaranteed by storing a minimal factorization. This orthogonality p...

A Jacobi-type updating algorithm for the SVD or URV decomposition is developed, which is related to the QR algorithm for the symmetric eigenvalue problem. The algorithm employs one-sided transformations, and therefore provides a cheap alternative to earlier developed updating algorithms based on two-sided transformations. The present algorithm as w...

Estimating the angles-of-arrival of wide-band emitters is an important problem in array processing. This paper introduces a novel method which is applicable if the sensor array consists of doublets. Furthermore the wide-band signals are modeled as the output of a linear time-invariant system driven by white noise. The novelty in our approach lies i...

This paper presents a novel, fully parallel algorithm for robust linearly constrained minimum variance beamforming. The robustness results from the use of an adjustable constraint to compensate for the unavoidable small mismatch between the nominal and the actual steering vector of the signal-of-interest. The need for parallelism follows from the l...

Factorizations of orthogonal matrices play an important role in modern digital signal processing. Here we focus on their usefulness in the field of recursive eigendecomposition methods. We concentrate on recursive algorithms which use Givens rotations to update the eigenvector matrix. The orthogonality of the estimated eigenvector matrix is known t...

A novel algorithm is presented for updating the singular value decomposition (SVD) in parallel. It is an improvement upon a Jacobi-type SVD updating algorithm, where now the exact orthogonality of the matrix of short singular vectors is guaranteed by means of a minimal factorization in terms of angles. Its orthogonality is known to be crucial for t...

High-resolution algorithms for direction finding of narrowband sources require a good estimate of the noise correlation matrix. We derive a physically motivated linear noise model. It is based on a Fourier expansion of the ambient noise field and is applicable to arbitrary antenna arrays. We also show that for contrived cases, a linear model may no...

We introduce a factored spherical SVD updating algorithm which can be used for subspace tracking. It is a non-iterative algorithm for approximate SVD updating. The orthogonal matrix tracking the signal subspace is parameterized as a sequence of Givens rotations. This factorization has two important advantages. On the algorithmic level it cures the...

This paper presents a novel, fully parallel algorithm for robust linearly constrained minimum variance (LCMV) beamforming. The robustness results from the use of an adjustable constraint to compensate for the unavoidable small mismatch between the nominal and the actual steering vector of the signal-of-interest. The need for parallelism follows fro...

This paper presents an efficient implementation of a real adaptive eigenfilter-bank, which makes use of the property that eigenvectors of a Toeplitz matrix are symmetric or skew symmetric. It is shown that the symmetric and skew-symmetric part can be adapted independently. As a result, the number of multiplications is roughly halved and the adaptiv...

A novel algorithm is presented for updating the singular value decomposition in parallel. It is an improvement upon an earlier developed Jacobi-type SVD updating algorithm, where now the exact orthogonality of a certain matrix is guaranteed by means of a minimal factorization in terms of angles. Its orthogonality is known to be crucial for the nume...

Recently the new class of so-called subspace methods for high-resolution direction finding has received a great deal of attention in the literature. When a real-time implementation is aimed at, the computational complexity involved is known to represent a serious impediment. In this paper, an ESPRIT-type algorithm is developed, which is fully adapt...

This paper addresses the problem of estimating the frequency content of a two-dimensional object, e.g. an image or a set of multi-sensor snapshots, stored in a matrix. The basic assumption is that the data matrix consists of a sum of 2-D complex sinusoids. Our algebraically coupled matrix pencils (ACMP) algorithm splits the 2-D problem into two rel...

High-resolution subspace algorithms have proved to be very useful in locating point sources radiating narrow-band waves. Here, we introduce a subspace method for estimating the angles-of-arrival of multiple wide-band signals, such as in acoustic emission. This state space approach is applicable under the assumptions that the sensor array consists o...

The authors proposes a novel, highly parallel subspace algorithm for adaptive high resolution direction finding (DF) of multiple wide-band emitters. The algorithm is a generalization of the computationally efficient narrow-band ESPRIT algorithm. For high-throughput real-time applications the algorithm can be mapped onto a Jacobi-type systolic array

This paper presents a novel, fully parallel algorithm for robust linearly constrained minimum variance beamforming. The robustness results from the use of an adjustable constraint to compensate for the unavoidable small mismatch between the nominal and the actual steering vector of the signal-of-interest. The need for parallelism follows from the l...

The direction-of-arrival (DOA) estimation problem consists in determining the angles of arrival of a number of signals impinging on a sensor array. Recently, the so-called ESPRIT method of Roy and Paulraj has received a great deal of attention in the literature. The method employs matrix decomposition techniques, such as singular value decompositio...