1. Hybrid Cochlear Implantation: Treatment for High Frequency Hearing Loss
PAULETTE MCDONALD, M.A.
JACKIE RENKER, B.S.

3. Hybrid defined by Merrimam-Webster: an animal or plant that is produced from two animals or plants of different kinds
: something that is formed by combining two or more things

4. Why Hybrid? New treatment option, New Indication
Word score assessment (CNC)
Significant Performance Increase
Unique Electrode Array
Integrated Sound Processor
FDA Approval for Hearing Preservation
Documented Two Ear Performance
This sets the stage for what Hybrid brings to our industry. More than just a device.
A new population of patients with a new indication.
Candidacy requirement word score to better reflect hearing loss
Significant improvement in performance outcomes – the average of which exceeding averages of traditional cochlear implant recipients
A new electrode array designed to maximize preservation and performance outcomes.
A fully integrated sound processor
Only FDA approved device for Hearing preservation
New data into the two-eared condition.

5. Why hybrid? Those patients where hearing aids are not helping
Ability to preserve hearing with the new electrode. A soft insertion technique which maintains the structural integrity of the apical portion of the cochlea.
Technology is available to combine acoustic and electric.

6. Wardrop et al,Hearing Res, 2005
A temporal bone study of insertion trauma and intracochlear position of cochlear implant electrodes
In this study, several very experienced surgeons, ones who we would all likely consider the “gold standard” implant surgeon, implanted a number of temporal bones under surgical conditions, and specimens were then analyzed.
Wardrop et al,Hearing Res, 2005

7. Wardrop et al, Hearing Research , 2004
Interestingly, the array design was what correlated most strongly with damage, as opposed to individual surgeons, which gives us hope that the implant companies can develop arrays that are ‘surgeon-proof’, as the 3 manufacturers currently are already doing or have done so.
Wardrop et al, Hearing Research , 2004

8. Types of trauma
Trauma to the delicate structures of the inner ear frequently occurs during insertion of the cochlear implant electrode Greatest damage occurs to the partition above the scala typmani..
Damaged ranged from minor displacement of the basilar membrane to seer fracture of the osseous spiral ligament and deviation of the electrode path from its intended path into the scala tympani to the overlying scala media or scala vestibuli.
It was found that even moderately severe intracochlear trauma resulted in reduced number of functional peripheral dendrites or spiral lamina,

9. FACTORS AFFECTING DAMAGE TO THE COCHLEA
Mechanical properties of a particular electrode design.
Variations in the size and shape of each cochlea.
The specific surgical techniques used for insertion of
the cochlea.
It is possible that damage to the medial surface
of the scala typmani which separates the
scala tympani from the internal auditory meatus
might serve as a pathway for infection
of the central nervous system.
ASK AMY TITLE REFLECTION

10. Conclusions
Because damage to intracochlear structures occurs most frequently to the partition above the scala tympani it has been proposed that an electrode array designed to minimize upward bending might reduce the incidence and severity of insertion related damage.
Wardrop, et al designed two different electodes that
were of a stiffer design and minimized upward
bending of the cochlea.
He concluded that more researched needed to be done.

11. Imaging and placement CI532 (Slim modiolar) electrode in Cochlea:
CI512 (Contour Advance) electrode in cochlea:

12. Békésys' PLACE Theory of Hearing
Georg Von Békésy found that hair cells near the BASE of the cochlea represent HIGH FREQUENCY coded for higher frequencies and as you moved down from the base and then moved to the APEX = LOW FREQUENCY .... SO THE PLACE from base to apex: determines or codes what frequency is perceived

13. Békésys' PLACE Theory of Hearing
Frequency of sound is indicated by the place on the organ of Corti that has the highest firing rate.
Hair cells all along the cochlea send signals to nerve fibers that combine to form the auditory nerve.
According to place theory, low frequencies cause maximum activity at the apex end of the cochlea, and high frequencies cause maximum activity at the base.

14. PLACE PITCH CODING a b c FREQUENCY IN HZ
16,000
8000
3500
1500
600
300 80 c
FREQUENCY IN HZ
Remember that pitch is coded in the brain, studies have shown that the brain does change the pitch percept. So the brain would reorganize and adjust the pitch for word understanding.
Schematic of a cochlea with superimposed place code. (a) depth of implantation
(b) conventional cochlear implant (c) short cochlear implant are indicated by the
Gray lines, with the black dots representing the active electrodes in the array.
Combined electro-acoustic stimulation: a beneficial union? K N Talbot, D E H Hartley,Clinical Otolaryngology 2008 Dec; 33 (6) :

15. Consider this patient 67 YO FEMALE
20 YEAR PROGRESSIVE SENSORINEURAL HEARING LOSS
USES NECKLOOP TO TALK ON THE TELEPHONE
NON PULSITILE TINNITUS BILATERALLY
BROTHER AND SON HAVE HEARING LOSS
NORMAL CAT SCAN
NORMAL BLOODWORK
DIURETIC THERAPY TO MAINTAIN HEARING LEVELS

16. Physiology of High Frequency Hearing Loss
Typical Hearing Aid Range
When there are no hair cells (dead regions) hearing aids can be ineffective. This is typically where cochlear implants are effective in stimulating the nerve directly .
Scanning electron micrograph of the cochlea
Typical Cochlear Implant Range
Hearing Aids are effective when hair cells are present to stimulate with acoustic amplification
In a subset of patients the sensory damage in the high frequency areas of the cochlea exceeds the amplification limits of hearing aid
Due to the healthy low frequency hearing individuals are not candidates for a traditional cochlear implant. When there is a dead region electrical stimulation is the best option.
Since hearing aids and traditional cochlear implants alone are not an option, there remains an unmet need for this population
Source: Vinay & Moore (2007)
Research conducted with scanning electron microscopy of the cochlea has shown that severe hearing losses greater than 70 dB can result in sensory hair cell loss including total loss
i.e sensory dead regions.

18. Why Hybrid Hearing? Audibility 125  6000Hz
Electric Hearing is critical for speech understanding
Benefits of Acoustic Hearing
Enhanced sound quality
Improved understanding in background noise
Fundamental frequency cues for both pitch and vowel discrimination
Interaural timing difference cues
Music appreciation
Good frequency resolution
Restores HF Sensitivity
Script:
The goal of Hybrid Hearing is to provide audibility 125 to 6000 Hz for those in-between candidates who may no longer benefit from hearing aids in noise and who do not yet meet the indication for traditional CI.
The Hybrid Implant System combines the best of both worlds for these individuals – electric hearing where they need it and continued access to acoustic information in the implanted ear (and via the contralateral ear as well).
Electric (i.e. CI) hearing is critical for speech understanding, where the acoustic low frequency information provides benefits such as:
{Read Slide}
You can definitely achieve some of these benefits in a bimodal fitting condition (and our recently announced Smart Hearing Alliance with GN ReSound was created to maximize bimodal fittings), but why not try to have it in both ears to allow the brain to access binaural redundancy or summation??
{Any questions so far?}
Hybrid Hearing is available for adult recipients (>18 years) who utilize the Hybrid L24 Implant System

19. Interaural time difference (ITD)
The difference in the arrival time of
A sound between two ears
Helps with sound localization by
Providing a cue to the direction or
The angle of the sounds source from
The head.
If you keep the low frequencies in both ears it helps maintain ITD Cue.

20. Hybrid Surgical Technique
Same approach as cochlear implant surgery
Specific care taken to protect hearing
–Similar approach to drill-out stapedectomy
–Diamond burr, slow speed, no suction of perilymph
–Slow insertion of the array
Cochleostomy (0.75mm –smaller than CI)
–Anterior to floor of round window membrane
Round window
–Used in European study with good results
Round Window
Cochleostomy

21. Factors that may enhance the preservation of residual hearing
Potential for Acoustic Trauma while drilling a cochleostomy
Vibration and Loudness Trauma
Mechanical Trauma due to electrode insertion that includes.
Insertion Angle and Location
Fracture to the osseous spiral lamina
Disruption of the basilar membrane or spiral ligament
Insertion Speed!!!!
Foreign Body Reaction
Electrode
Bone dust and/or blood
Inflammation – Short Term/Long Term
Stimulation Over Time
Stimulation induced degradation of hair cells.
Round Window
Electrode Technology
Soft Surgery/ Steroids?
6. Kiefer J, Gstoettner W, Baumgartner W, et al. Conservation of low frequency
hearing in cochlear implantation. Acta Otolaryngol
2004;124:272Y80.
7. Di Nardo W, Cantore I, Melillo P. Residual hearing in cochlear
implant patients. Eur Arch Otorhinolaryngol 2007;264:855Y60.
Electrode Length

22. Background: >15 years of research
8 year FDA trial of 50 adult subjects
1st implantable FDA-approved for treatment of HF SNHL
FDA-approved March 2014
1st Hybrid implant (U.S.) April 16, 2014
1st and only cochlear implant labeled for potential preservation of RH
1st indication using CNC words
1st integrated electric+ acoustic SP
1st trial publication July 2015 Laryngoscope
2 Post-Approval Studies Ongoing:
Longitudinal hearing preservation and performance data to 5 years
Up to 100 subjects implanted
Script:
So, how did we get to the trial, to the FDA approval and where are we now? A little background for you…
I would be remiss not to thank the University of Iowa and Dr. Bruce Gantz who helped to pioneer this entirely new category of cochlear implant electrode array.
As you know, the Nucleus Hybrid L24 Implant System is the first and only electro-acoustic cochlear implant system available today.
{Read list of firsts from slide}
As many of you may know, we have two post-approval studies going on that are gathering long term data on these subjects as well as on newly implanted subjects where we will continue to learn more about this treatment option.
Hybrid Hearing is available for adult recipients (>18 years) who utilize the Hybrid L24 Implant System

23. Cochlear® Nucleus™ Hybrid L24 Implant
Designed to restore access to hearing in higher frequencies through electrical stimulation. 1
Soft Tip for Minimal insertion trauma 4
15 mm of active length 2
Apical Diameter: .25mm 5
Tapered basal stiffener designed for a smooth, single motion insertion
22 platinum electrode contacts
Shorter electrode than current electrodes and slimmer to help prevent trauma and designed for scala typmani every time and it is softer which reduces or eliminates fracturing of the Basilar Membrane. 3 6
Basal Diameter: .4mm 7
White Stopper at 16mm to indicate a full insertion 8
Surgical Handle located opposite of the electrode contacts to assist with electrode orientation and atraumatic insertion

24. Hybrid™ L24: An Expanded Indication
Ear to be Implanted
Aided CNC word score between 10% and 60% correct, inclusively
Contralateral Ear
Aided CNC word score better than ear to be implanted but less than 80% correct
Audiometric
Severe to profound HF SNHL bilaterally
Adults
aged 18 years and older
unilateral implantation of poorer ear
Script:
What we see here is the FDA-approved indication for the Hybrid L24 Implant System, resulting from our trial with the 50 subjects. These are the minimum criteria the FDA considers imperative for application of the Hybrid solution to a candidate.
Naturally, there are other candidacy considerations outside of the indication such as duration of hearing loss, stability of loss, etiology, general health, lifestyle, communication needs, cognitive load, age, etc. that should be considered for all candidates alike.
Duration – recommended to be less than years
Stability – a duration is not defined in our labeling, however, should you be asked, you can say that during CI2015, the discussions around this aspect of EAS fittings referenced stable audiograms for the last (roughly) 6-18 months, but did not further define (as in X dB or less is considered stable). It would really fall to the individual clinic’s judgement.
General Health – diabetics, as an example, or those with other autoimmune diseases may not have stable thresholds over time
As you can see from the shaded audiogram here on the left hand side of the screen, this implant is indicated for adults with a precipitously sloping high frequency sensorineural hearing loss. And as you will also note, this is a “healthier” ear than we have previously implanted – in the last years, the indications for implantation have undoubtedly expanded, and the Hybrid indication is by far the most broad in the industry and really opens up the discussion of treating both ears and assessing the whole patient.
I draw your attention to the dB range here. As we know from the literature, you do not open the cochlea and insert a device “for free” and a drop in hearing thresholds may be anticipated, so, you want to choose your candidates carefully as clinicians will want to see low frequency thresholds that are better than (i.e. lower than) about dB so that they can fit the acoustic portion of the N6 to the loss.
By the same token, candidates typically do not choose an implantable solution because their hearing and hearing aids are serving them well in noisy situations; instead, they typically report that they chose an implantable solution to get back what they are missing – due to their HF SNHL and its impact on their speech perception.
We are often asked about the “borderline” candidate – if someone meets traditional CI indications, they should receive a traditional CI. The Hybrid implant is intended for candidates who do NOT meet traditional CI indications.
{ASK: How are we doing so far? What questions can I address here?}
Hybrid Hearing is available for adult recipients (>18 years) who utilize the Hybrid L24 Implant System

25. Cochlear Hybrid Hearing Zone
Post Implant Thresholds:
Pure tone thresholds <85 dB HL anywhere between 250Hz Hz are candidates for hybrid hearing.
Once a person has received their Hybrid implant, they may be a candidate for cochlear hybrid hearing using the Cochlear acoustic component with the Nucleus 6 sound processor. The black bordered translucent area on this audiogram shows the Hybrid Hearing Zone, or the candidacy range for a patient’s ability to use hybrid hearing via the combination of acoustic and electric hearing in the same ear.

26. What about frequency lowering technology
Over 30 years of research with FLT
–Multiple variations of FLT
•Little to no benefit (< 10-percentage points) for:
–Phonemes
–Consonants
–Plurals
–Vowels
•Few reported significance at the group level
•Did not use same measures as CI studies
–Does not allow for across-technology comparison
studies have looked at the effects of the low frequencies on music appreciation, pitch recognition,
It has many benefits, however in our hybrid patient s their hearing pattern is so severe that they may not see benefit (eg hearing loss starting at 750 Hz and not 2KHz)
Glistaet al., (2009). IntJ Audiol., 48: Simpson et al., (2005) IntJ Audiol., 44: Robinson et al.,(2007). IntJ Audiol, 46: Kuket al., (2009). JnlAm AcadAud, 20:

27. FlT Gifford
“There were no statistically significant differences between conventional amplification (CA) and DFC for any of the measures tested.”
Summary of Results:
•No significant benefit for speech understanding in quiet or noise for patients with Hybrid-qualifying audiograms
•Same metrics used in the Hybrid-L trial
-CNC and AzBio
•No improvement in subjective benefit with FLT
The hybrid patient
It works well with patients who have very high frequency hearing loss and loss in the 1000 Hz.

28. Case #2
Pre-op
Post-op
AzBio: 2%
AzBio: 93%

29. Case #7
Pre-op
Post-op
AzBio: 38%
AzBio: NA

30. Case #7
6 WEEKS POST

31. Case #8 Pre-op Post-op AzBio: 48% AzBio: 39%
Hearing is better following implantation. Only 10 % improvement, 80 years old
Had a change in hearing while in FLA]
Started AVT and received a new hearing aid in her right ear and now feels she is doing better.
AzBio: 48%
AzBio: 39%

32. Average Pre-op thresholds
Large ORANGE bars represent median (quartile 1 to quartile 3)
Whisker bars represent range
Raw data is on next (hidden) slide

33. Average Post-op thresholds
*9/10 patients maintained thresholds ≤ 80 dB at 250Hz and 500 Hz and could take advantage of acoustic component post-op
Not the amount that they drop it is whether they can use their acoustic portion or not.

34. Average Performance (1 month)

35. Post op hearing results
Combined electro-acoustic stimulation: a beneficial union? K N Talbot, D E H Hartley, Clinical Otolaryngology 2008 Dec; 33 (6) :
Is electric acoustic stimulation better than conventional cochlear implantation for speech perception in quiet?
Adunka OF1, Pillsbury HC, Adunka MC, Buchman CA., Otol Neurotology Sep;31(7):
Electric-acoustic stimulation of the auditory system: a review of the first decade.
von Ilberg CA1, Baumann U, Kiefer J, Tillein J, Adunka OF., Audiol Neurootol. 2011;16 Suppl 2:1-30.
United States multicenter clinical trial of the cochlear nucleus hybrid implant system.
Roland JT Jr1, Gantz BJ2, Waltzman SB1, Parkinson AJ3; Multicenter Clinical Trial Group,
Laryngoscope Jan;126(1): .

36. cONCLUSIONS
Hybrid provides an option for a severe high frequency hearing loss
Hybrid implant is able to preserve residual in most patients
Even if hearing thresholds fall off the patients are likely to perform better than they did prior to implantation
Functional residual hearing is more important than measured thresholds post-op.

37. THERE IS ALWAYS BASKETBALL
THANK YOU !