Chapter 3. Basic considerations; the effect of low MPO on gain

3. Basic considerations; the effect of low MPO on gain What is the effect of a relatively low MPO? Figure 3.1 shows the audiogram of a patient with conductive hearing loss. Cochlear thresholds and LDLs, according to Dillon and Storey (1998), are indicated in Figure 3.1B.        Figure 3.1. Figure A ( upper left) shows the audiogram; figure B (upper, right) present the cochlear thresholds and the LDLs (Dillon & Storey, 1998). Figure C (lower figure) shows the MPO values (labelled Read more [...]

Chapter 4. Longevity and a new fitting model

4. Longevity and a new fitting model  4.1 Introduction An attempt is made to develop a fitting model based on an acceptable partial use of the dynamic range of hearing. Audibility of normal conversational speech, with its 30 dB wide speech range, is an important factor in that model. A new goal has been formulated: at least 35 dB of the dynamic range of hearing should be accessible with a device; that means that with proper amplification conversational speech is audible (Zwartenkot et al., Read more [...]

Chapter 5. Comparison of interventions in certain groups of patients

5. Comparison of interventions in certain groups of patients 5.1. Congenital middle ear and outer ear anomalies 5.1.1. Surgical repair or amplification? When counselling patients with hearing loss caused by congenital ear anomalies (like aural atresia), firstly, reconstructive surgery should be considered. Congenital ear anomalies might vary from mild (middle ear anomalies) to severe (atresia of the ear canal) with an associated air-bone gap from 40 to 65 dB. Amongst otologists, reconstructive Read more [...]

Chapter 6. Bilateral application should always be considered

6. Bilateral application should always be considered 6.1 Introduction Bilateral hearing refers to hearing with two ears. When listening with two ears instead of one, at least four advantages can be distinguished: 1) loudness summation, 2) use of acoustic head shadow to hear better in noisy places, 3) directional hearing and 4) binaural squelch. In normal hearing listeners binaural hearing is obvious, based on accurate processing of the bilateral inputs, leading to a ‘fused’ percept (binaural Read more [...]

Chapter 7. Challenges in children; critical choices

7.1 Introduction; children should not be treated as young adults Counselling adults, who according to their audiogram should profit from amplification, is not always successful. Adults might deny their hearing problems or postpone a hearing aid trial. If their attitude is more positive, they might only be interested in hardly visible devices, even if speech recognition with such devices is not optimal. For children, there is less room to move because the better the hearing the higher the chance Read more [...]

Chapter 8. Sensorineural hearing loss

Part 2. Challenges and limitations of implantable hearing devices (auditory implants) for sensorineural hearing loss  8. Sensorineural hearing loss  8.1 Auditory implants for moderate to severe sensorineural hearing loss To rehabilitate sensorineural hearing loss, conventional air-conduction hearing aids are the first choice (e.g. behind-the-ear devices or BTEs; Figure 2.1, chapter 2). If the sensorineural hearing loss is not too severe, it is possible to make conversational speech audible Read more [...]


Appendix 1 About the author: Ad Snik studied physics at the Eindhoven University of Technology and got the master’s degree in 1976. In 1982, he acquired the doctor’s degree from the same university with a thesis entitled ‘Visco-elastic properties of monomolecular layers’. After two years of lecturing Physics and Electronics, he specialized in medical physics and was registered in 1987 as a medical physicist/ audiologist. In 1988 the author was employed as a clinical audiologist and researcher Read more [...]

References and Abbreviations

References Aarnisalo AA, Vasama JP, Hopsu E, Ramsay H. Long-term hearing results after stapes surgery: a 20-year follow-up. Otol Neurotol. 2003;24:567-71. Agterberg MJ, Hol MK, Cremers CW, Mylanus EA, van Opstal J, Snik AF. Conductive hearing loss and bone conduction devices: restored binaural hearing? Adv Otorhinolaryngol. 2011;71:84-91 Agterberg MJ, Frenzel H, Wollenberg B, Somers T, Cremers CW, Snik AF. Amplification options in unilateral aural atresia: an active middle ear implant or a bone Read more [...]