Participants:

Akoestische Bouwprojecten, Netherlands

http://www.abpadvies.nl

ABC International Trade, Netherlands

http://www.vreeswijkindustrials.nl/

Hörzentrum Hannover, Germany

http://www.hoerzentrum-hannover.de/

Universiteit Antwerpen, Belgium

http://www.ua.ac.be/

Otoconsult, Belgium

http://www.otoconsult.com/

Vrije Universiteit Amsterdam, Netherlands

http://www.vu.nl/

Radboud University Nijmegen, Netherlands

http://www.ru.nl/clst/

Medizinische Hochschule Hannover, Germany

http://www.mh-hannover.de/

Karel De Grote Hogeschool, Belgium

http://www.kdg.be/

http://www.cisiad.uned.es

Directory: 

Opti-Fox

CI fitting is the process of programming the implant to the individual anatomy, physiology and other patient-related parameters. To date this is a very tedious and laborious job which is executed by highly expert audiologists, engineers, medical doctors etc. With more than 200.000 CI users worldwide and an annual increase of over 30.000, finding the skilled professionals and the time to perform the fitting, becomes an ever-increasing problem and a real bottle neck to the further implementation.

On top of this, CI fitting as a process is not yet at the stage of being well controlled, standardized or mature as professional discipline. Huge variation exists between the different approaches of different experts. No universal guidelines exist, no formal training, no established “Good Clinical Practice”.

The Eargroup has been addressing these issues since many years. Process optimization requires valid tests to monitor outcome and systematic procedures to standardize and drive the process.

• Since audiometry and speech audiometry were judged insufficient to monitor the coding of the different components of sound, A§E has developed. This is a psychoacoustical test suite that is language independent and feasible in the clinical practice. Different test modules have been and are still being developed to assess the coding of intensity, spectral and temporal content of sound at the level of detection, discrimination and identification. See A§E for more details and instructional videos.
• FOX (Fitting to Outcome eXpert) is a software tool under development to systematize the fitting procedure. In its present form, it is a rudimentary intelligent agent that runs deterministic logic (the “Eargroup Advice”) to read and interpret the cochlear implant program and the measured psycho-acoustic outcome obtained with this program. Based on this analysis, it executes the advice and proposed changes to the CI program. The audiologist can accept these changes and program them to the CI speech processor. FOX is currently being investigated and validated in clinical trials in several CI centres in Europe and India.

Opti-Fox focuses on both pillars of the Eargroup approach.

• Outcome measuring:
  • If more emphasis is going to be put on psycho-acoustic outcome measurements, it is of paramount importance to create state of the art and well calibrated test conditions. Good criteria and working principles have been defined by several international standards. At this moment they require expensive and space-taking sound-treated rooms and equipment. Opti-Fox will try to create other test conditions that assure the same acoustic test quality while reducing the cost and required space substantially. Input from engineers and acousticians is crucial for this enterprise.
  • Speech audiometry remains a cornerstone in the monitoring of CI performance. This test, however, is time-consuming, language-specific and highly dependent on the linguistic skills of the test person. These are serious drawbacks for the universal usability of speech audiometry for the purpose of process-optimization. An attempt will be made to reduce these drawbacks by making the test less language-specific, more adapted to the individual linguistic skills and less dependent on professional time. Input from linguists and speech technologists is crucial for this enterprise.
• Process automation
  • At this stage, FOX is a rudimentary piece or artificial intelligence (AI). Opti-Fox will attempt to improve the level of AI by modeling the functional relations between the many variables involved and by adopting one or more self-learning strategies to improve the accuracy of the advice given. Input from computational technology and AI specialists is crucial for this enterprise.

Update Sept 2011

The project activities have been divided into 4 Work Packages:

• WP 1: Language-independent Speech-(in-Noise) testing
  • The first task of this WP consisted in a detailed state-of-the-art with respect to speech audiometry in the native languages of the SME- and RTD-partners involved in the OPTI-FOX consortium. Research consisted in a presentation and critical discussion of existing tests for Dutch- and German-speaking testees in view of the criteria and norms of the word lists used in these tests.
  • Secondly, recordings were made of speech samples of typical and atypical (e.g. hearing impaired) listeners in view of the development of a tester-independent speech audiometric test battery. In order to be able to develop a language-independent template for this test battery a metric was established to determine the representativeness of a speech or text sample of a given language, based on the linguistic features of that language. As the metric will be used to build lists of words that serve as acoustical prompts in speech audiometry, priority was given to a distance measure evaluating the use of graphemes to represent the sound system of a given language.
  • Finally, this WP was also concerned with the development of a software engine to segment text into word lists, apply filters on charachter count and present these words visually for use in WP2.

• WP 2: Objective automatic speech error analysis
  • The aim of this WP is to introduce automated speech analysis in speech audiometry testing. Firstly, a number of concerns regarding accuracy and robustness of such an analyses that might compromise its validity in the present medical context, have been addressed. The focus has been mainly on inter-person variability analysis in order to design an assessment method that is able to detect differences between two acoustic realizations of the same word spoken by a single speaker. Available techniques were explored in order to provide a ‘dissimilarity measure’ for the difference between them.
  • Secondly, this WP was also concerned with the development of a software engine to record the words from WP1 as wave files after visual and acoustic prompting and to analyze these wave-files by means of common ASR technology. At the conclusion of this reporting period, some 180.000 wave files from more than 200 different speakers (Flemish, Dutch, German) have been recorded and analyzed.

• WP 3: Optimization of the automated fitting process for cochlear implant speech processors
  • Within this WP new powerful methods, algorithms and software tools for tuning cochlear implants are being built that are intended to overcome limitations of manual trial-and-error. The first stage of the project consisted in problem understanding, data collection process, data formats and an exploratory analysis of available data.
  • The second stage consisted of data modeling and the design of the application. Relations were captured between electrical input (map settings) and psycho-acoustic output (outcomes of tests) variables. The key question to be answered with help of data modeling was which cochlear implant parameters should be changed, and by how much, in order to obtain a desired change in the results of a specific test. Currently, several approaches to develop an optimal tuning strategy are being explored, ranging from general optimization methods to the most recent methods that were developed in the field of active learning.

• WP4: Test box for cochlear implant testing
  • The goal of this WP is to develop a test box with ideal conditions for the measuring of psycho-acoustic outcomes with cochlear implants. The box should be able to (i) exclude external noise (acoustic insulation) as defined by ISO standards, and (ii) to produce an exact acoustic replicate of an electric input signal (a simulation of ANSI Type 1 free field testing). The requirement with respect to the acoustic insulation of the test box focused on efficiency within the set limits of weight, size and cost price. In a first stage, an inventory was made of available norms, specific requirements and possible technology to be used. In a second stage a first prototype was build.

Final results

We have developed 3 products which together will drastically change the technical fitting of cochlear implants:

• Otospeech

Otospeech is a psycho-acoustical test to assess the auditory performance of cochlear implant users in a universal and automated way; universal in that it will be usable in a huge number of different languages and that it will be independent of dialect of lexical knowledge; automated in that the scoring of the speech intelligibility will be done in an automated way; this will allow the apllication to run as a self-test.

• Fox

Fox is being optimized to become an AI (artificial intelligence) application which analyzes the electrical parameters of a cochlear implant together with the psychoacoustical test results obtained with it and which will produce recommendations for changing the electrical parameters such that the outcome will improve to target; this application models the many input variables as a function of the many output variables and uses probabilistic network technology. We are currently undertaking to develop the final application in such a way that it will be self-learning by continuous analysis of the growing data set.

• Otocube

Otocube is a portable desktop module with integrated amplifier, loudspeaker and soundcard, which allows the psycho-acoustic testing and fitting of CI-users in standardized and calibrated conditions without the need of sound-treated test rooms with highly specialized and expensive audiological equipment.

(–)  A Büchner, Th Lenarz, R Battmer, R Goetze, I Mosinier, S Borel, H Cooper, C Fielden, Z Vanat, J Muff, T Nunn, A Britz, F Vanpoucke, D Gazibegovic, P Govaerts. Computer assisted outcome based fitting: preliminary results of the FOX study in Advanced Bionics’ users. 10th EFAS conference, Warsaw, Poland. POSTER COMMUNICATION.

(–)  Z Szlavik, B Vaerneberg, W Kowalczyk, P Govaerts. Opti-Fox: towards the automatic tuning of cochlear implants. Proceedings of the 20th Belgian Dutch Conference on Machine Learning. 2011; 79-80.

(83)  Vaerenberg B, Govaerts PJ, De Ceulaer G, Daemers K, Schwauwers K. Experiences of the use of FOX, an intelligent agent, for programming cochlear implant sound processors in new users. Int J Audiol 2011; 50: 50-58.

(81)  Govaerts PJ, Vaerenberg B, De Ceulaer G, Daemers K, Schwauwers K. Development of a software tool using deterministic logic for the optimization of cochlear implant processor programming. Otol Neurotol 2010; 31(6): 908-18.

(73)  Daemers K, Yperman M, De Beukelaer C, De Saegher G, De Ceulaer G, Govaerts PJ. Normative data of the A§E® discrimination and identification tests in preverbal children. Cochlear Implants International 2006; 7(2): 107-116.

(72)  Govaerts PJ, Daemers K, Yperman M, De Beukelaer C, De Saegher G, De Ceulaer G. Auditory speech sounds evaluation (A§E®): a new test to assess detection, discrimination and identification in hearing impairment. Cochlear Implants International 2006; 7(2): 97-106.

PRESS

Date	Publication
19/04/2011		FOX helps audiologists to tune cochlear implants for the hearing impaired
21/05/2012		Geautomatiseerd aanmeten van cochleaire implantaten
06/2012		Gepassioneerd tot over de oren

A§E

The Auditory Speech Sounds Evaluation is a set of supraliminal auditory tests. It is conceived to test children with no or very limited functional speech, but it can also be used for other persons with hearing problems.

Fitting Fox

Fox^® is an intelligent agent for the expert based, outcome driven fitting of hearing aids and cochlear implants

Otocube

Otocube is a revolution in testing CI-patients. It is a high-tech and portable desktop box which replaces a fully equipped audiological room. It outperforms a clinical booth in acoustical insulation and contains all electronics, high-end amplifier and loudspeaker to deliver well calibrated sound between 10 and 120 dB HL to the CI processor in the box. Close the box and take a long headpiece cable to transfer the sound from the processor to the patient’s ear. The box easily connects “plug and play” to your laptop or PC. Thanks to our custom-made audiological software A§E, you readily perform audiometry, speech audiometry in any language, loudness scaling, spectral discrimination, temporal fine structure tests, etc. Otocube will be available early 2013 on http://www.cishop.net. Specifications of Otocube can be found on http://www.otocube.com.

Otospeech

The first application to allow patients to do speech-audiometry on their own! The main idea of the application is that it builds an individual set of 300 words for every single patient. The selection is sampled from a website of his daily reading, making sure that the lexicon is familiar to the patient. In addition, Otospeech guarantees that the selected words are phonetically representative for the patient’s native language (validated for over 20 languages). The words are recorded by the patient himself in a 30 minute-session. This removes all possible bias due to language or dialect. During later test sessions, Otospeech presents these words acoustically in lists of 25, just like in regular speech audiometry and asks the patient to repeat them in the microphone. Then Otospeech scores the words based on innovative technology with highly accurate acoustical analysis. We have obtained 85% correlation between Otospeech’s scoring and manual scoring on standard speech audiometry for different languages. Otospeech will become available soon as yet another A§E module. Contact us for more information.