Design of hearing aid shells by three dimensional laser scanning and mesh reconstruction

Hearing aid shells (or earmolds) must couple the hearing aid with the user's ear. Earmolds have to fit the subject's outer ear canal properly to ensure a good performance of the aid. Because of the great variability in the anatomical pattern of the ear, earmolds are custom made. At present, an impression of the subject's ear canal is taken and used to fabricate the silicon-made mold. The postimpression activities that typically are performed during the fabrication process modify the physical dimensions of the resulting earmold and thus affect the fit of the product. A novel system for 3-D laser scanning and mesh reconstruction of the surface of ear canal impressions is presented. The reconstructed impression can be digitally stored and passed directly to dedicated CAD 3-D printing machines to model the silicon earmold and thus achieve the best possible fit. The proposed system is based on a couple of cameras and a commercial laser for the surface digitization and on a straightforward algorithm, based on the deformation of a geometric model, for the reconstruction of the acquired surface. Measurements on objects of well-known geometric features and dimensions are performed to assess the accuracy and repeatability levels of this 3-D acquisition system. Robustness to noise of the proposed reconstruction algorithm is determined by simulations with a synthetic test surface. Finally, the first measurements (acquisition+reconstruction) of closed surfaces from ear canal impressions are reported

Inventory of current EU paediatric vision and hearing screening programmes

Background: We examined the diversity in paediatric vision and hearing screening programmes in Europe. Methods: Themes relevant for comparison of screening programmes were derived from literature and used to compile three questionnaires on vision, hearing and public-health screening. Tests used, professions involved, age and frequency of testing seem to influence sensitivity, specificity and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists and audiologists involved in paediatric screening in all EU fullmember, candidate and associate states. Answers were cross-checked. Results: Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% more than once. First measurement of VA varies from three to seven years of age, but is usually before the age of five. At age three and four picture charts, including Lea Hyvarinen are used most, in children over four Tumbling-E and Snellen. As first hearing screening test otoacoustic emission (OAE) is used most in healthy neonates, and auditory brainstem response (ABR) in premature newborns. The majority of hearing testing programmes are staged; children are referred after one to four abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand. Conclusion: Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1-4) and funding sources (8)

FIAPAS

Número extraordinario conmemorativo del 25 aniversario de FIAPASLos Programas de Detección e Intervención Precoz, están produciendo una revolución en el campo de la audición infantil que afecta a los aspectos pato-fisiológicos de la discapacidad auditiva periférica y central, al desarrollo tecnológico de las audiometrías, al desarrollo cognitivo, lingüístico y del habla y al desarrollo de la gestión sanitaria. En el artículo se analizan los beneficios de la Intervención Precoz, los sistemas que se utilizan en Europa y Estado Unidos, los modelos y protocolos de Detección e Intervención Precoz y el futuro de estos sistemas.MadridBiblioteca de Educación, Ministerio de Educación, Cultura y Deporte; C/ San Agustín 5; 28014 Madrid; Tel.+34917748000; [email protected]

Preface

Increasing evidence indicates that screening and early treatment of hearing disability have the potential to significantly improve the quality of life and extend the functional status of adult population[...