2017 Sec 1 Green Book

D. R. FRIEDMANN ET AL.

treatment. Subjective improvement of localization and speech understanding in difficult listening situations in real-life situations with the addition of the second ear after implantation may actually be more important than our ability to quantify this with currently available tools and methods. It is possible that the tests currently being used are not sensitive enough to accurately reflect sub- jective patient reports until a certain level of competence is reached. As we move forward with evaluating SSD candidacy for cochlear implantation, it will be important to devise measurement tools that can better reflect the binaural advantage in the sound field in the presence of a normal or near-normal ear. Next we consider the factors that we use to consider candidacy for SSD CI on the basis of our experience so far. Candidacy Considerations As observed in Table 1, our patients were diverse in their baseline characteristics including both demo- graphics and audiometric characteristics. In some patients, the better hearing ear was in the normal range, but threatened in some way as in the case of an inner ear malformation predisposing to progressive hearing loss or as yet minimally symptomatic retrocochlear pathology in an only-hearing ear. Patients differed significantly in their motivating factors for pursuing cochlear implan- tation be it tinnitus suppression, trouble in difficult listening situations, or anticipated hearing loss in an only-hearing ear. Many more patients with SSD have been evaluated for cochlear implantation at our center and this experience has allowed us to define the following parameters for SSD CI candidacy. Patients with late stage Me´nie`re’s disease may struggle with intractable vertigo from an ear essentially nonfunc- tional from an auditory perspective. With a simultaneous labyrnthectomy and ipsilateral cochlear implant, patients can have definitive treatment of their vertigo while bringing their ‘‘ear back to life’’ all during an outpatient ambulatory procedure. In 2013, Hansen et al. reported on the results of cochlear implantation in patients with Me´nie`re’s disease who progressed to profound sensor- ineural hearing loss with one ear. They reported signifi- cant improvement in word and sentence scores, though ability to localize sound in this cohort showed much more modest improvement (13). We have had similar experi- ence with our cohort and we think this provides a hopeful option for patients who have often had years of suffering with their disease to both alleviate their vertigo and rehabilitate their hearing. Absolute Indication: An ‘‘At Risk’’ Only Hearing Ear Though rare, a threatened only hearing ear, for example, an acoustic neuroma or other retrocochlear pathology, is an important consideration for a cochlear implant. These patients live in fear of the possibility of 1 day waking up suddenly deaf ill equipped to handle the Absolute Indication: Late Stage Unilateral Me´nie`re’s Disease

More recently, his father reports he has not worn his implant at all over the last few months. Of note, family dynamics seem to play a role in this patient’s device use. The third pediatric patient was 3 years old at the time of implantation. As of the 3-month postoperative evalu- ation, PBK-word scores were 96%with the nonimplanted ear alone and 32% with the implant alone. In the bimodal condition the word score was 96% attributable to the ceiling effect from having one normal hearing ear. Importantly, the combined signal did not cause a decre- ment in performance. On the sentence test, with noise- front she scored 100% in the nonimplanted ear, 70% with the CI alone, and 100% in the bimodal condition. Her father reports that the patient no longer asks where sound is coming from and responds better to sound in general. Overall, the children demonstrated varying degrees of open-set speech perception in the implanted ear and bilat- eral improvement in the presence of background noise. However, these few children introduce some of the issues related to expectations after a prolonged duration of deaf- ness and the impact of device use on performance. Most recently, a family presented with their 6-month old who was diagnosed with sensorineural hearing loss. The family had done extensive research and asked many appropriate questions. At their request, the child under- went a cochlear implant evaluation at our center. After extensive counseling, the family elected to proceed with cochlear implantation, at the age of 11 months. There are not yet any postoperative data available. Perhaps the least understood aspect of unilateral hear- ing loss is determining if and when treatment is indicated. Some patients have to the ability to adapt well without any intervention. Although adults who have experienced postlingual SSD can endorse certain deficits or listening difficulties, the same cannot be assumed of children. Experience suggests that some children benefit from noninvasive interventions; however, determining optimal treatment and timing for a given patient remains a challenge. Some children and adults also overcome such deficits without intervention. The other available treatment options for SSD do not restore hearing to the affected ear and hence, lack the advantages of binaural hearing that require sound to arrive at each ear independently for the processing of timing and pitch differences to be integrated by the brain. It should be noted that both the CROS and bone-anchored hearing aids may have undesirable effects in certain listening situations including hearing in noise, especially when noise is present on the side with the implant and may be routed to the better hearing ear, worsening the signal-to-noise ratio and making listening more difficult. Cochlear implants may overcome these issues, but should not be expected to restore all of the benefits of binaural hearing. Studies such as our own on SSD CI are hampered by our inability to fully measure the efficacy of the DISCUSSION

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