Final Word | July 2019 Hearing Review

A patient was referred by a friend because she has been having difficulty with her hearing aid fitting. She reported a diagnosis of vestibular migraine and severe hearing loss in her right ear and “some hearing loss” on the left. She noted that she was originally fit with a hearing aid on the affected right side and had difficulty with discomfort from the amplified sound and not appreciable benefit from the fitting. The team working with her added a second hearing aid after more than a year of repeated visits in an attempt to better address her needs. After a number of months of return visits without success, she sought another opinion from me.

My assessment confirmed her complaint that aiding the poorer ear was more of a distraction than a benefit because of distortion and intolerance to audible amplified sound. We went over her choices, going forward. I recommended that she remove the hearing aid on the poor ear for now and focus on the benefits she receives from the aid on the better side. We discussed future options including continuing with the monaural fit, or working with a CROS/BiCROS system to add audibility to the “shadow side” of her head.

I’ve had experience with CROS/BiCROS aids since 1976 when some of the first wireless systems became available. However, since I don’t deal with them daily, and may not be familiar with all systems in the current market. I contacted C. Scot Frink, AuD, a few months ago. He often posts information about CROS/BiCROS systems on professional social media, and has lectured on alternative approaches such as AmpCROS. He made some helpful suggestions at the time, and I filed them away for future use.

Following a few weeks of using the monaural hearing aid, the patient returned with more questions about CROS systems. I explained that when conditions were such that she needed to hear speech on the poorer side, activating a CROS microphone will often help, but if there is unwanted sound on that side, she may have poorer performance. Preferential seating and switching the aids from CROS, to BiCROS, to monaural will be necessary for optimal benefit. She’s a young, 60ish, technology-savvy individual and doesn’t see the interactivity with the hearing aid as a problem compared to the bad experience she had with amplification before, and ordered a system. She was pleased with the initial fitting, and is adapting very well.

I’m glad to have her as a patient, but am curious what had happened to drive her away from her former audiologists. I didn’t ask who fit her, but from her description, it sounded like proper procedures were followed. However, her care was provided by several different clinicians as professionals joined and left the practice over time.

I’m not sure I would have started out any differently with this patient if I had been working with her at the outset. I very likely would have explored fitting the poorer ear initially as well, as long as testing and her subjective reaction supported the decision. She was frustrated with the fact that she had to return multiple times without a favorable outcome. In her experience with the former office, the serial nature of the visits apparently lost the continuity of care and she ended up dissatisfied. It was easy for me to take a fresh look at the situation since I didn’t “own” the previous fitting, and could offer an alternative strategy that better suits her.

Aiding asymmetric losses—especially in cases with very distorted perception of speech and discomfort—can be very frustrating. I think trying amplification initially is required, but the process will be difficult, especially when there is a better ear to compare to. I once had a patient with asymmetry who griped constantly about the quality of speech in his poorer ear with amplification.  Following an unfortunate sudden loss of hearing in his better ear, his opinion of the sound in the opposite ear changed dramatically as it became his only hearing ear. The idea of providing some stimulation to the poorer ear (if it can comfortably be used for spatialization or to augment clearer signals sent to the other side) is appealing if it ultimately brings benefit to the patient.

The Final Word? Unilateral total or severe hearing loss that precludes the use of hearing aids is a big challenge for people who may have lived most of their lives hearing binaurally. CROS systems provide some relief, but require extra counseling and proper switching and use by the patient for optimal benefit. Going forward, we are seeing cochlear implants emerging as an option, even for those with normal hearing on the opposite ear. It’s off-label for now in the United States, but the anecdotal reports are encouraging.

I want to extend kudos to Dr Frink for answering my email and offering good suggestions, and to Cliff Olson, AuD, for offering straightforward advice to clinicians and consumers (see his YouTube video “Alternative Treatment for Single Sided Deafness (SSD): AmpCROS vs CROS, BiCROS, & BAHA Hearing Aids” at

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Citation for this article: Van Vliet D. Problems in fitting asymmetric hearing losses. Hearing Review. 2019;26(7):34.