ABSTRACT
Since 2001, the World Health Organization (WHO) reported on adult-onset hearing loss when publishing data on the global burden of disease in the World Health Report. Hearing loss has become a major global health issue, affecting about 15% of the world’s adult population. In 2015, approximately half a billion of people (˜6.8% of the world’s population) suffered from moderate to profound hearing loss (defined in Table 4.1). If left untreated, this unaddressed hearing loss (greater than 35 dB in the better-hearing ear) poses an annual cost in the range of $750–$790 billion globally. It has to be noted, that these estimates do not cover expenses such as hospital outpatient visits, sign language interpreters and family out-of-pocket payments. Thus, the actual economic burden of hearing loss is assumed to be even higher than $750–$790 billion globally.
Treatments for hearing loss include hearing aids, cochlear implants, middle ear implants, bone conduction implants, and other assistive devices. Which treatment fits the patient best depends on the individual anatomy, and the severity (mild, moderate, severe, and profound) and the type (conductive, sensorineural, and mixed) of hearing loss. Hearing aids and implants have entrenched as cost-effective strategies in treating hearing loss. Still, the current production of hearing devices meets less than 10% of the global need and estimates indicate that about 72 million (untreated) people with hearing loss could potentially benefit from the use of a hearing device. One device that represents a promising solution for a large part of this 10% is the “Vibrant Soundbridge” middle ear implant. The following chapter focuses on the outcomes regarding safety, efficacy/effectiveness and subjective benefit of the Vibrant Soundbridge (VSB). Both the middle ear implant “Vibrant Soundbridge” and the vibroplasty couplers will be discussed. The VSB offers a safe and effective alternative for patients with various middle ear pathologies and has become a profound strategy for hearing rehabilitation, leading to improved quality of hearing and life. The VSB leads to an improvement of speech understanding in the “Freiburger Sprachtest” at 65 dB of about 41 % in sensorineural hearing loss (SNHL), 55.5 % in mixed hearing loss (MHL) and 78.1 % in pure conductive hearing loss (CHL), respectively. Data collected on speech perception in noise reflect even more heterogeneity in methods. It is only possible to say that in general test scores improved with the VSB. Patient satisfaction and performance with the Soundbridge have been high and consistent across centers, countries, and continents, evidenced by the data and reports in numerous publications and presentations. In general, patients who wear the device all day long (up to about 16 h, some patients even sleep with it on), report a natural sound quality, high device satisfaction, and a better ability to understand especially in noisy environments. Again, the number of available testing tools outweighs the results; the most frequent ones being the Abbreviated Profile of Hearing Aid Benefit (APHAB) and the Glasgow Benefit Inventory (GBI). In all studies reporting on subjective outcomes, patients benefit from a VSB (and hearing aids, either in addition or compared to), but there are major differences within the subscales (background noise, reverberation, ease of communication, aversiveness to sound). In general, the VSB is described as much more comfortable, clearer in sound perception and fewer events of unease are reported.
In conclusion, the VSB can be a safe tool in surgically experienced hands. As there are no standard operating procedures to compare functional outcomes or measure subjective qualities of device performance the data measured are rarely comparable. Nonetheless, the VSB turns out to be a highly reliable device that significantly improves perception of speech in noisy situations with a high sound quality. The applications of the VSB in mixed and CHL have widened the therapeutic spectrum to improve hearing in those patients who could not be treated effectively enough yet. Adverse events are below the range for conventional ME surgery and bone conduction hearing implantation; and the audiological outcomes demonstrate a long-term effectiveness. Kosaner Kliess and colleagues recently in 2017 showed that it is also a very cost-effective solution in terms of costs [measured as incremental cost-utility ratio (ICUR)] of AUD 9913.72 per QALY being below a willingness-to-pay threshold of AUD 34,500 in the Australian healthcare setting.
