Acoustically Optimized Venting (AOV): Custom Innovation offers unprecedented user satisfaction

Stäfa, Switzerland, 2nd April 2008 - Hearing Care Professionals are always on the lookout for solutions that enhance the overall experience of wearing hearing instruments. Acoustically Optimized Venting (AOV) is just such an option, particularly effective at addressing the age-old issue of own-voice annoyance related to the occlusion effect in In-The-Ear devices. AOV in the new Exélia CIC Petite is a Phonak innovation that takes the guesswork out of vent selection, using a sophisticated, new process to guarantee individualized, optimal venting in the smallest instrument possible with natural sound quality.

One of the most-common problems encountered with hearing instruments is a phenomenon known as occlusion, when sounds such as the wearer's own voice or chewing are prevented from escaping through the ear canal. These sounds are reflected back to the eardrum, making them seem unnaturally loud to the wearer. The effects can be so unpleasant that many users
prefer to forgo the benefit of their hearing instruments and remove them.

In the past, attempts to minimize occlusion included the use of larger vents, but in earlier systems this often compromised the amount of applicable gain. And although feedback cancellation systems with modern digital hearing aids - allowing larger vent sizes - have dramatically improved the situation, too large a vent can sacrifice the minimal size. Custom instruments are often severely space-constrained, so a small instrument can often not offer both a large vent and still have enough space for the electronic components.

Now, with Exélia CIC Petite and Acoustically Optimized Venting, Phonak combines several methods to surmount the challenges and increase end-user satisfaction.

Creating an acoustically optimized vent

As the only manufacturer to master sophisticated, fully integrated, digital custom product manufacturing technology, Phonak now combines patient's hearing loss data with the physical dimensions of the ear canal to create a customized vent that successfully reduces occlusion while preserving high-frequency amplification.

Using the patient's individual audiometric data and scanned ear impression, the software computes an "acoustic mass target value" based on a multidimensional equation that considers audiometric thresholds, target gain requirements and potential for occlusion and feedback. The 3D instrument modeling software then designs the vent precisely by manipulating the shape, diameter and overall length. At the same time the designer ensures the smallest possible instrument size by optimizing the placement of internal hearing aid components within the shell.

All this information is stored digitally and transferred to the hearing instrument during the final stages of the production process. Finally, at the fitter's office, the iPFG fitting software uses this information to optimize the frequency response, the feedback management setup and other parameters to provide ideal insertion gain with extremely natural sound quality and virtually no occlusion.

Sophisticated Swiss precision

The amount of sound that escapes through a vent depends not only on its diameter but also
on its length and shape, and positive results - higher end-user comfort, in-ear stability and wearer satisfaction - can be achieved with a variety of configurations. An acoustically optimized vent is not necessarily very large: it is simply the one that best meets the wearer's needs. For users who require an open fitting, the Phonak system can create the largest possible vent while WhistleBlock technology offers up to 20dB added dynamic stable gain.

Clinically proven

In a US field trial conducted in late 2007, the Exélia CIC with AOV was compared with other open-fit device styles including CRT (receiver in the ear) and micro BTEs with slim tubes. The data from the field study showed that the Exélia instruments with AOV offered measurable benefits in four major areas that affect fitting success: audibility, occlusion, smoother response and feedback management. All areas were improved or significantly improved. Clearly, AOV offers a viable choice for customers wanting an open fit device in a cosmetically appealing size without compromising sound quality.

About Phonak

Headquartered near Zurich, Switzerland, Phonak has developed, produced and globally distributed state-of-the-art hearing systems and wireless devices for over 50 years. The combination of expertise in hearing technology, mastery in acoustics and strong cooperation with hearing care professionals allows Phonak to significantly improve people's hearing ability and speech understanding and therefore their quality of life.

Phonak offers a complete range of digital hearing instruments, along with complementary wireless communication systems. With 2500 employees worldwide, Phonak drives innovation and sets new industry benchmarks regarding miniaturization and performance.

For more information, please visit www.phonak.com or the Phonak Web Channel on Audiology Online.