CHEMOTHERAPY INDUCED HEARING LOSS Reducing the impact of chemotherapy induced hearing loss with new hearing aid technology Cisplatin-based chemotherapy is a known risk factor for hearing loss. Although most literature suggests hearing loss with cisplatin occurs at higher frequencies and with higher doses of the drug, traditional teaching has been that patients with pre-existing hearing loss should not receive cisplatin, meaning these patients often have inferior cancer outcomes. However, if these patients are adequately counselled, it is thought many would prefer to have better cancer outcomes if there was some ability to correct hearing loss, or retune hearing aids to address further falls in hearing. Another question is whether modern hearing aids can reduce tinnitus. In order to find out more, ANZUP member A/Prof Andrew Weickhardt spoke to Alison Hennessy from Alison Hennessy Audiology.
without feedback and without needing to close/occlude the ear canal (our earlier way of dealing with feedback). This has improved comfort and cosmetics drastically for people with high frequency hearing loss. Hearing aids do not restore normal hearing. This is typically noticed more in noisy/ challenging situations. We know that hearing loss (sensorineural loss) causes not just a loss of sensitivity, but also a reduced ability to ignore the background noise and focus on the signal of interest. There are a number of factors including age and cognitive function, in addition to the degree of sensorineural hearing loss. I do a screening test of the ability to hear speech in noise with appropriate amplification in order to counsel the person appropriately regarding expectations, and in order to decide the level of noise reduction technology likely to be required. Modern hearing aids aim to identify/reduce the background noise. For some people this is very effective, for others, no amount of high tech processing overcomes their reduced ability to cope in challenging situations (e.g. multi-talker conversations).
Current thinking about tinnitus is that much of the issue of Hearing aids are capable of amplifying more high dealing with tinnitus is due to underlying fears regarding frequency sounds than previously. ‘Frequency’ refers to the tinnitus (e.g. “it will get worse” and “it will make me the pitch of the sound (treble or bass). Higher frequency deaf”). It is thought that these may be subconscious speech sounds tend to be the consonants. These provide thoughts. Therefore, management of clarity. Lower pitched speech tinnitus typically involves reassurance sounds tend to be vowels. in the first instance. The aim of tinnitus Thirty years ago, the upper THE COST OF HEARING AIDS management is habituation (i.e. it is still limit of amplification was Hearing Services Program there, but it is not noticed, or noticed Under the Hearing Services Program, the 3-4kHz. Now it is fairly typical Federal Government funds hearing services only infrequently). Sound therapy can to see hearing aids amplifying (tests, etc) and hearing aids if required. The be part of the management and most up to 6-8 kHz and sometimes hearing aids are low-end technology, but do modern hearing aids have ‘tinnitus’ feature some noise reduction and feedback to 10kHz. Generally speaking, cancelling capabilities. More expensive hearing programs – where a sound generated if someone has hearing loss aids may be partially funded by the scheme. in the hearing aid is used to reduce only at 6kHz and above, they Hearing aids awareness of the person’s tinnitus. In would not be considered If paying privately, it is approximately $3,000 my experience, the best sound therapy hearing aid candidates as the – $8,000 for a pair of hearing aids. This will for people with significant tinnitus generally include fitting and review/re-tuning impact of such a hearing loss appointments for a certain period of time. issues and hearing loss is the use of is not regarded as functionally Health insurance extras cover typically provides hearing aids (tinnitus programs usually a reimbursement of $300 – $1,500. The NDIS significant. has strict criteria regarding the degree of not required). hearing loss, but will also fund hearing aids and Earlier hearing aids often services. The expected ‘life’ of hearing aids is Many people are reluctant to consider produced feedback when five years. hearing aids as they have only seen providing significant high Hearing tests big hearing aids. My comment is that frequency amplification. Some clinics are able to bulkbill everyone while many people are wearing hearing aids Nowadays, feedback some can bulkbill only as part of Team Care that you do not see – you only see the Arrangement (referred by GP) or if referred by cancelling technology is an ENT or neurologist. Therefore, patient costs obvious ones.” quite advanced, allowing can vary from nothing up to $150 or more. Re-tuning/review appointments after the initial high frequency amplification period attract a similar consultation fee. ANZUP UPdate Spring 2018 | 31
