Week 10 EAS

Question 1

EAS approval dates for each manufacturer

Answer 1

• cochlear= march 2014
• med-el= September 2016
• AB= not approved, but can use it with Naida technology because they did not come up with a new internal device, just an external device that had EAS capabilities

Question 2

EAS electrodes size

Answer 2

• shorter electrode
• –lateral wall instead of perimodiolar
• –cochlear hybrid L24= 16 mm lateral wall
• –med-el FLEX 24= 20.9 mm lateral wall
• smaller in diameter and more flexible- designed for lateral wall insertion
• –the major goal is to prevent cochlear damage which is achieved by surgical measures
• traditional electrodes can preserve hearing too (in about 55% of pts)

Question 3

hearing preservation with CI

Answer 3

• large part is the surgical technique
• –soft surgery is the goal and this would cause less damage
• average threshold shift for 125-750= 14.4-16.4 dB in a study
• AB HiRes 90K had 31.6% preservation
• med-el sonata had 50% preservation
• cochlear advance contour had 59.2% preservation

Question 4

what happens if there was a failure to preserve hearing with a hybrid array

Answer 4

• re-implantation with a conventional length electrode
• –improved speech scores in noise and quiet after re-implantation
• keep short electrode with adjusting map
• –limited benefit to the patient
• –recommendation of using longer array because of this for the instances when hearing is not preserved so that the array will give some benefit
• —–cochlear used to have 6-10mm electrodes until 2008

Question 5

current EAS processors

Answer 5

• clinical trial processors
• –cochlear freedom
• –med-el DUET and DUET 2
• approved processors
• –cochlear N6 (CP910/920) and N7(CP1000)
• –Sonnet and Sonnet 2
• other processors
• – AB Naida CI Q90

Question 6

main difference between EAS with Nucleus 6 and Nucleus 7

Answer 6

nucleus 6 had one receiver option while 7 has a 60, 85, and a 100

Question 7

how to set the EAS frequency boundary

Answer 7

• Meet approach meaning where acoustic stops is where electric begins
• overlap approach meaning there is a big of a range which gets both electric and acoustic stimuli
• gap approach meaning there is a frequency range between the acoustic and electric ranges which gets no stimulation
• pts preference for meet approach
• no significant difference if you found exactly the last frequency perceived electrically and then do acoustic from there or if you use a best guess of that frequency
• –however the meet approach in general is better in noise and is more natural than other approaches

Question 8

specifics for where to set up the cutoff frequency for acoustic stimulation

Answer 8

• pts with significant low frequency HL=overlap
• pts with better preserved hearing=meet
• the benefits of acoustic amplification are limited when thresholds exceed 70 dB HL
• –better sentence recognition in noise when electrical cutoff was set to a freq where unaided thresholds exceeded 70 dB HL

Question 9

clinical protocol for programming EAS devices (8 steps)

Answer 9

1) otoscopic exam
2) eval implant site
3) measure Ac/BC thresholds for implanted ear
- –starting from 125 Hz and every octave and interoctave frequency afterward
- –allow 4 weeks before activation for middle ear effusion to resolve; conductive component may persist
4) possibly eval for the presence of cochlear dead region with the TEN test
5) conduct in situ real-ear probe mic measured to eval output of the acoustic component of the EAS device
- –determine gain and maximum otuput for HA portion
- –find the cut-off freq for acoustic amplifications (<70 d threshold)
6) determine low-freq boundary for the electric signal through “meet” approach
7) measure T-levels for all functional intra-cochlear electrode contacts (inf needed)
8) balance upper-stimulation levels in loudness across the electrode array

Question 10

EAS Mapping in Cochlear

Answer 10

• after opening the Custom Sound software
• –select the acoustic component
• –view audiogram
• –method and compression
• –earmold
• –frequency boundary
• –9 channels-adjust MPO/gain
• –need real-ear measures like regular HAs
• –then adjust T and C levels, and balance

Question 11

EAS Mapping with Med-el

Answer 11

• after opening the Maestro software
• –add audiogram
• –select the acoustic component
• –select audiogram and apply first fit
• –activation of processor
• –volume control (default and range)
• –appearance–Target 40, 65, 90 dB

Question 12

EAS advantages

Answer 12

• improved speech discrimination
• –one year post-op: open-set sentences–71% (pre-op 24%)
• ——poorer EAS benefit associated with poorer pre-op WRS and longer duration of high-freq deafness (>30)
• preserving the LF hearing allows the recipient to utilize the inter-aural timing cues–better speech understanding in noise as a result
• –normal hearing–score 50% with -30dB noise and -15 dB multi-talker babble
• –traditional CI–score 50% with +3 dB noise and +8 dB multi-talker babble
• –hybrid CI–score 50% with -9 dB noise and +8 dB multi-talker babble
• better speech in noise and better localization
• better music perception

Question 13

predictive variables for post-op outcomes for adults

Answer 13

• there is currently no definitive predictive variables for post-op speech recognition
• –age: provided the pt is medically cleared, no compromised cognitive status or dementia, they can receive substantial benefit regardless of age
• –audiometric thresholds: not a real predictor
• –pre-op speech score is a good predictor
• –duration of deafness is also a good predictor (0-20 years= god, over 20 is worse)
• –integrity of cochlear and neural structures (ANSD/Neuroma) are good predictors
• –etiology is also a good predictor
• —–meningitis= poor
• —–otosclerosis= poor depending on ossification and the number of usable electrodes can decrease over time
• –if the etiology is temporal bone fracture need to make sure there is no damage to the VIII nerve

Question 14

predictive variables for post-op outcomes for peds

Answer 14

• age at implantation
• –big factor and better if implanted under 13 months than 16-23 months which was still better than 24 months
• —–if implanted under 1 yr then they have similar word learning abilities as children with normal hearing, but still benefit regardless of time
• intervention which is early and consistent gives better oral language outcomes
• pre-implant audio thresholds do dictate success (language access before implant or not)
• etiology
• –meningitis can dictate because of ossification and central effects and damage to neurons
• –syndromes-related deafness can still have positive outcomes and if thy are losing vision want to implant ASAP
• –chromosome related depends on cognitive abilities
• –abnormal cochlear anatomy most benefit but come more than others
• integrity of cochlear and neuro structures plays large role
• –CMV depends on cognitive abilities
• family variables
• additional abilities can benefit but it might not be language benefits

Question 15

family variable affecting outcomes with CI for peds

Answer 15

• family size (bigger=better)
• intelligence
• SEC
• maternal education
• regularly attending audiology appts
• children wearing CIs regularly
• amount of time spent talking to the child at home

Question 16

5 specific syndromes with deafness in peds and their CI outcomes

Answer 16

• Connexin 26 mutation=excellent outcome
• pendred syndroe= excellent outcome with enlarged vestib aqueduct but poorer if other deformities present
• CHARGE syndrome= poorer outcomes than that of a typical Ci recipient due to cochlear nerve deficiency and cognitive disorders
• brachial-oto-renal syndrome, Refsum disease, Usher syndrome, and Waardenurg syndrome
• –if hearing and vision are worsening then do CI ASAP due to wanting to keep one sense