Projects

Effects of Daily Processor Use

CI manufacturers have recently included the ability to track average daily CI use within the programming software making these objective data readily accessible to clinicians and researchers. Using this capability, our group investigated the relationship between hours of CI use per day and speech recognition outcomes. We found a statistically significant and strong correlation between hours of CI use per day and word recognition as well as sentence recognition suggesting that higher average daily use is associated with better performance. In a subsequent project, we recruited adult CI users with poorer than average daily CI use, motivated them to increase their daily CI use, and assessed performance before and after CI use increase. This study showed that an increase in daily CI use over a one-month period translated to improved speech recognition performance. To further understand daily habits and barriers to CI processor use, we also created the Cochlear Implant Use Questionnaire. This work has shown that consistent daily CI processor use is integral to optimizing CI outcomes and should be considered in all future outcome studies.

Holder JT, Dwyer NC, Gifford RH. (2020). Duration of processor use per day is significantly correlated with speech recognition abilities in adults with cochlear implants. Otology & Neurotology.

Holder JT, Mayberry LS, Gifford RH. (2021). The Cochlear Implant Use Questionnaire: assessing habits and barriers to use. Otology Neurotology.

Holder JT, Gifford RH. (2021). Effect of increased daily cochlear implant use on auditory perception in adults. Journal of Speech, Language, and Hearing Research.

Normative Benchmark Data

We recognized the need to understand the current abilities of our patients and how they compare to age-matched listeners with normal hearing. Despite widespread use of the updated Minimum Speech Test Battery (MSTB) by the majority of CI clinics in the U.S., there were no published age-normative data for young children or older adults against which clinicians could benchmark CI users’ outcomes. To address these gaps in the literature, we recruited 81 adults 20-79 years of age and 41 children 5-12 years of age with normal hearing. We assessed sentence recognition in noise for AzBio/BabyBio sentence recognition test (5 signal-to-noise ratios), BKB-SIN, and QuickSIN. These data were published and presented, and they are now being used clinically to guide goal-setting, counseling, and expectations. These efforts confirmed that we still have a lot of work to do in terms of improving outcomes for cochlear implant recipients to elevate them to the performance of their typically hearing peers. Perhaps the easiest way to improve outcomes for potential CI candidates is to help them gain access to the technology. In 2018, we reported on the current profile of adults presenting for preoperative cochlear implant evaluation for 287 patients. We found that our patient population is largely looking similar to foundational CI studies, suggesting that greater awareness and insurance accessibility may be needed to increase access to CI technology, an initiative toward which the American Cochlear Implant Alliance, manufacturers, and CI professionals are strongly aligned.

Holder JT, Sheffield SW, Gifford RH. (2016). Speech understanding in children with normal hearing: Sound field normative data for BabyBio, BKB-SIN, and QuickSIN. Otology Neurotology. 37(2): e50-e55.

Holder JT, Levin LM, Gifford RH. (2018). Speech recognition in noise for adults with normal hearing: age-normative performance for AzBio, BKB-SIN, and QuickSIN. Otology Neurotology, 39(10): e972-e978.

Holder JT, Reynolds SM, Sunderhaus LW, Gifford RH. (2018). Current profile of adults presenting for preoperative cochlear implant evaluation. Trends in Hearing. 22:1-16.

Hearing Preservation and Electric Acoustic Stimulation (EAS)

Hearing preservation and electric acoustic stimulation are generally thought to provide benefit for CI recipients; however, there remain many unknowns regarding the integration of electric and acoustic stimulation especially for children. In 2021, we explored the benefit of this technology in a case series of children with TMPRSS3, a relatively rare genetic mutation thought to affect hair cells and spiral ganglion cells. This series showed that early cochlear implantation even in the presence of normal low frequency hearing yielded favorable CI outcomes for these children. Further research is warranted to better understand best fitting practice and the expected EAS benefit for patients of all ages.

Holder JT, Morrel WG, Rivas A, Labadie RF, Gifford RH. (2021). Cochlear implantation and electric acoustic stimulation in children with TMPRSS3 genetic mutation. Otology Neurotology.

Roberts J, Stecker GS, Holder JT, Gifford RH. (2021). Combined electric and acoustic stimulation (EAS) in children: investigating benefit afforded by bilateral versus unilateral acoustic hearing. Otology Neurotology.

Nassiri AM, Yawn RJ, Holder JT, Dwyer RT, O’Malley MR, Bennett ML, Labadie RF, Rivas A. (2019). Hearing preservation outcomes using a precurved electrode array inserted with an external sheath. Otology Neurotology, 41(1), 33–38.

Electrode Array Type & Placement

Electrode type and placement are two factors thought to contribute to CI outcomes. Using image reconstruction methods proposed by Noble and colleagues, our group has been able to pair audiometric outcome data with electrode array location information. While many groups have found no difference in outcomes between straight and precurved arrays, our data show that precurved arrays result in significantly better performance, if the array is entirely located within scala tympani. Additional benefits are realized with precurved electrode arrays placed in close proximity to the modiolus. Another aspect of electrode array placement crucial to performance is the presence of extracochlear electrodes. In a sample of 262 patients, 13.4% of patients had at least one extracochlear electrode of which 40% required a CT scan for identification. This finding supports the notion that cochleae vary in size and “complete insertion” may vary from patient to patient; however, it is important to detect and deactivate extracochlear electrodes so that high-frequency information can be reallocated to areas with better electrode neural interface.

Holder JT, Kessler D, Noble J, Labadie R. (2018). Prevalence of Extracochlear Electrodes: Computerized Tomography Scans, Cochlear Implant Maps, and Operative Reports. Otology & Neurotology, 39(5): e325-e331.

Holder JT, Yawn RJ, Nassiri AM, Dwyer R, Rivas A, Labadie RF, Gifford RH. (2019). Matched cohort comparison indicates superiority of precurved electrode arrays. Otology & Neurotology.

Morrel WG, Holder JT, Dawant BM, Noble JH, Labadie RF. (2020). Effect of Scala Tympani Height on Insertion Depth of Straight Cochlear Implant Electrodes. Otolaryngol Head Neck Surg.

Labadie RF, Schefano AD, Holder JT, Dwyer RT, Rivas A, O’Malley M, Noble JH, Dawant BM. (2019). Use of intraoperative CT scanning for quality control assessment of cochlear implant electrode array placement. Acta oto-laryngologica.

Electrocochleography (ECochG) Measured through the Cochlear Implant

The disadvantage of intra- or postoperative CT scanning is that the resulting clinical decisions are reactionary and do not provide information regarding underlying neural health. To address this disadvantage, we have been completing electrocochleography during CI insertion to provide the surgeon with real-time feedback and to estimate residual hearing levels in combination with our imaging techniques. The result of this data collection was a pioneering paper I co-first-authored with Dr. Brendan O’Connell, which led to the development of a multi-center, randomized clinical trial and international ECochG meeting in New York, November 7-9, 2019.

O’Connell B*, Holder JT*, Dwyer R, Gifford RH, Noble JH, Bennett M, Rivas A, Wanna G, Haynes DS, Labadie RF. (2017). Intra-and postoperative electrocochleography may be predictive of final electrode position and postoperative hearing preservation. Frontiers in Neuroscience, 11, 291.

Koka K, Riggs WJ, Holder JT, Dwyer R, Ortmann A, Mattingly JK, Harris MS, O’Connell BP, Adunka OF, Buchman CA, Labadie RF. (2018). Intra-cochlear electrocochleography during CI electrode insertion is predictive of final scalar location. Journal of Hearing Science, 8(2).

Riggs WJ, Dwyer RT, Holder JT, Mattingly JK, Ortmann A, Noble JH, Dawant BM, Valenzuela C, O’Connell BP, Harris MS, Litvak LM, Koka K, Buchman CA, Labadie RF, Adunka OF. (2019). Intracochlear Electrocochleography: Influence of Scalar Position of Cochlear Implant Electrode on Post-Insertion Results. Otology Neurotology.

Harris MS, Riggs WJ, Giardina CK, O’Connell BP, Holder JT, Dwyer RT, Koka K, Labadie RF, Fitzpatrick DC, Adunka OF. (2017). Patterns Seen During Electrode Insertion Using Intracochlear Electrocochleography Obtained Directly Through a Cochlear Implant. Otology Neurotology, 38(10): 1415-1420.