77f1631ed920ba7b5a0ff4c4b8855239.ppt
- Количество слайдов: 50
Cochlear Implants: Where We’ve Been, Where We’re Going Amber M. Gardner, Ph. D. , CCC-A University of Virginia Health System
Early Attempts… n Alessandro Volta – early 1800 s became the first to stimulate the auditory system electrically Two metal rods in his ears (approx. 50 V) n “a boom within the head” followed by a sound similar to that of boiling thick soup n
Early Attempts… Realization made over the next 50 -60 years that since sound is more of an alternating signal, stimulating with DC wasn’t going to produce an adequate hearing sensation n Duchenne – 1885 – used an alternating current n n “the beating of a fly’s wings between a pane of glass and a curtain” n Improving, but not there yet…
Early Attempts… n Brenner – 1868 – published study that revealed hearing sensation was better using negative polarity. Also found that a reduction of unpleasant side effects could be achieved with correct placement of the electrodes
Early Attempts… 1930 s – thermonic valve (vacuum tube) was introduced and this allowed greater precision in electrical stimulation n Wever & Bray (1930)– electrical response recorded near the auditory nerve of a cat was similar (freq. & amplitude) to sounds to which the ear had been exposed n
Early Attempts… n Gersuni & Volokhov (1936) First to demonstrate that with electrical stimulation hearing sensation still remained after removal of tympanic membrane & ossicles – theorized the cochlea was the site of stimulation
Early Attempts… n Stevens & Jones (1939) – Listed several mechanisms that produced hearing when the cochlea was stimulated electrically Electrical energy could be converted into sound by a direct effect on the basilar membrane that would vibrate maximally at a point determined by the frequency – these vibrations would stimulate the hair cells n Direct stimulation of the auditory nerve produced a crude hearing sensation. n
Early Attempts… n 1940 s & 1950 s – Researchers began to realize that if more precise hearing sensations were to be produced stimulation of the auditory nerve fibers must be more localized vs. widespread current.
Early Attempts… 1950 – Lundberg stimulated the auditory nerve during a neurosurgical operation. Used a sinusoidal current - patient only heard noise. n 1957 – Djourno & Eyries – placed a wire directly on the auditory nerve (cholesteatoma surgery). Initially pt. just heard “a roulette wheel” & “a cricket” but was eventually able to differentiate pitch and identify several words. n
Getting Closer n Doyle et al (1964) inserted an electrode array (4 electrodes) into the cochlea of a deaf patient n n Patient was able to repeat phrases Simmons (1966) inserted an electrode array into the cochlea with more precision (closer to the modiolus) n Patient had ability to determine signal duration length and tonality was achieved
Almost There Early 1970 s - Michelson and House - insertion of electrode array through scala tymani driven by implantable receiver stimulators. n 1972 – speech processor developed to interface with the House 3 M single electrode implant & was commercially marketed. n n Single channel devices - very poor speech understanding (especially in open set)
Multi-channel Cochlear Implant Rod Saunders – First multi-channel CI patient (1978) Courtesy: Cochlear
Increasing Channels - Speech n Channels will increase from 1 to 2, 2 to 4, 4 to 8 to 32 – note the improvement in quality.
Increasing Channels - Music n First you will hear the song with 4 channels, then 8, then 16, then 32 – finally you will hear the original. Demo
Trends in Candidacy 1985 1990 1998 Today Age of Implantation Adults age 18 or older Adults & Children age 2 years or older Adults & Children age 18 months + Adults & Children age 12 months + Onset of Hearing Loss Postlinguistic Adults & Pre/Postlinguistic Children Pre/Postlinguistic Adults & Children Degree of SNHL Profound Severe-to-Profound Adults Profound Children Severe-to-Profound Adults, Children > age 2 Profound children < 2 years old Adult Speech Scores (open–set) 0% 0% 40% or less sentences in quiet 50% on sentences in quiet in ear to be implanted, with 60% or less in contralateral ear or binaurally Pediatric Speech Scores N/A 0% Lack of auditory progress, Less than 20% pediatric word tests Lack of auditory progress, 30% or less on pediatric word tests
3 FDA Approved CI Manufacturers Cochlear – 1985 n Advanced Bionics – 1996 n Med. El – 2001 (1994 – European release) n
Speech Processor (1978) Courtesy: Cochlear
Speech Testing (1978) Courtesy: Cochlear
Cochlear – Portable Speech Processor 1980 – 2 nd Recipient (George Watson) Courtesy: Cochlear
Nucleus 22 Device Courtesy: Cochlear
Wearable Speech Processor (WSP) 1982 Courtesy: Cochlear
From WSP to Mini Speech Processor (MSP) 1986 Courtesy: Cochlear
CI 22 M (Mini 22 Implant) n n n Courtesy: Cochlear Magnet Flexible receiver antenna 1988
MSP to Spectra n Courtesy: Cochlear Introduced in 1988 to go with the CI 22 M
CI 24 M n n n Courtesy: Cochlear 1997 Removable Magnet Monopolar electrodes Telemetry – can measure impedances Stimulation rates increased
Spectra to Sprint n n n Courtesy: Cochlear 1997 Increased number of program slots More flexibility
Esprit n n Courtesy: Cochlear 1998 First BTE processor from Cochlear
Esprit 3 G n n Courtesy: Cochlear 2002 (24 users) 2004 (22 users)
Freedom n n Courtesy: Cochlear n 2005 - New internal & external devices Same processor for BTE, bodyworn options New “Smart Sound” features
System 5 n n n Courtesy: Cochlear Launched Sept. 8, 2009 Internal device – thinner, but same technology platform External – thinner, more water resistant, autophone, 2 way remote control
Advanced Bionics History Company started by Al Mann in 1993 n 1996 - received FDA approval for adults n 1997 - received FDA approval for pediatrics n
Advanced Bionics n n n Courtesy: Advanced Bionics 1. 0 – 1994 (adults) 1. 2 – 1996 (adults), 1997 (pediatrics) CII ~ 2000
Hi. Res 90 k n n n Courtesy: AB 2003 Titanium (vs. ceramic) housing Removable magnet
AB – Body Worn Processors Courtesy: Advanced Bionics 1. 0 - 1994 1. 2 - 1996 S-Series ~ 1999 PSP~ 2001
AB – BTE Speech Processors Courtesy: Advanced Bionics Platinum BTE 1998 CII BTE 2000 Auria & Harmony 2003 & 2006
Med. El History 1975 - Hochmairs begin development of cochlear implant n 1977 - Multi-channel CI implanted in Vienna n 1989 - Med. El is founded n 1991 - Industry first BTE speech processor (trials) n 1994 - European approval of Med. El system n 2001 - FDA approval of Med. El system n 2003 - FDA approval of MRI compatibility (. 2 n
Med. El Internal Devices n Combi 40+ Introduced 1996
Pulsar CI 100 and Sonata Pulsar – September 2005 (Ceramic Housing) n Sonata – September 2007 (Titanium Housing) n Magnet fixed n Courtesy: Med. El 38
Tempo+ Speech Processor (1999) Lightest BTE Processor n Up to 9 Programs n One processor – multiple wearing options n Courtesy: Med. El 39
Opus 2 Speech Processor 2007 Ergonomic switch free design n Wireless FM n Fine Tuner – bilateral support, volume, sensitivity & telecoil switches n Courtesy: Med. El
Future Directions Greater number of bilateral recipients n Hybrid/EAS cochlear implants n Totally implantable cochlear implants n
Bilateral CI n Benefits Improved localization n Improved speech in noise performance n n Insurance Coverage - class action law-suits
Hybrid/EAS - Electric-Acoustic Stimulation n Combination of CI & HA n High frequency information - shorter electrode array n Low frequency information - HA (typically mild to moderate HL) n n Still in clinical trials in US n n Med. El Duet Approved in Europe (2007) All 3 companies still in US trials Courtesy: Med. El 43
Hybrid/EAS n European & trial data indicates patients are performing significantly better with EAS than CI alone or HA alone n n Noted especially in music & speech in noise Points to consider Risk of damage to residual hearing acuity during original insertion of electrode array n What is the course of action if hearing acuity changes and HA is no longer beneficial - additional surgery with new/standard array? n
Totally Implantable Cochlear Implant (TICI/TIKI) n Internal Components Rechargeable battery (lithium ion) n Microphone (subcutaneous) n Speech processor n n External Hardware Battery recharger n On/Off n Volume/Sensitivity n
TIKI
Totally Implantable Cochlear Implant (TICI/TIKI) n Benefits n No external parts n able to “hide deafness” n no cables, mics. . . to break n Able to hear 24 hrs a day (in shower, while sleeping. . . )
Totally Implantable Cochlear Implant (TICI/TIKI) n Disadvantages Larger internal device - more surgical time/larger incision n Battery will have to be replaced (approx. 6 yrs) n n Replace only battery or entire device? n Hear “body noises” (breathing, swallowing). Some people are unable to adjust to these.
TIKI Results 3 patients implanted Melbourne n Able to have “invisible hearing” or use 3 G processor n Hearing acuity n TIKI - Mild to moderate HL (improving to mild HL after 6 months) n 3 G - Hearing WNL n n Speech discrimination - CNC Lists TIKI - 33% (Improved as compared to pre-op) n 3 G - 77% n
Thank you
77f1631ed920ba7b5a0ff4c4b8855239.ppt