Implanting Prelingually Deaf People
Does it make sense to implant people who have never
heard, or at least never understood, spoken language? Is there any hope
that they can learn to understand spoken language? What are realistic
expectations for someone who has never understood spoken language? Read
on!
We
normally think of cochlear implants as being particularly effective with postlingually
deaf people. Read the thoughts of a Prelingually
Deaf Recipient concerning the performance of his cochlear implant.
June 2001 - Speaking of CIs and prelingually deaf adults, a New York
University School of Medicine study recently evaluated the success of
CIs in prelingually deaf adults. The results may
surprise you!
December 2005 - Family wins CI insurance victory
December 2007 -
Cochlear Implant Outcomes and Quality of Life in Adults
with Prelingual Deafness
~~~~~~~~~~~~~~~~~~~
We
are all familiar with the success stories of post-lingually deaf people
who get cochlear implants. But we don't hear much about the perceptions
of pre-lingual deaf people who have implants. Here are some thoughts
from one pre-lingually deaf man who was recently implanted.
"All
I can say is that a CI is nothing like a hearing aid, not even that
close. On my hookup, perceptually, it's entirely a new sense to me - had
no idea what I was "sensing." It didn't feel like hearing at
all like I did with my hearing aids. I realized that it would be very
difficult for prelingually deaf adults to adjust. It took me awhile to
realize that the sensations I had were actually sounds.
"A
good example of how much different a CI is compared to my HA:
"I
have a profound deafness. I can hear low deep sounds very well but
cannot hear high frequency sounds very well. With my HA, low-pitched
sounds sound LOUDER than high pitched sounds. I would play the keys on
the left side of piano because I can hear them well.
"With
my CI, it's completely reversed!!! Perceptually, low-pitched sounds are
a lot less loud while high-pitched sounds are a lot louder. I was upset
because I've always loved hearing low-pitched sounds and I wasn't sure
if it's normal to have that kind of "reversed frequency"
hearing. When I asked my hearing friends, they all say that low-pitched
sounds are perceptually less loud than high pitched sounds on a same
volume! That I didn't know!
"There
are three major perception changes that are common in prelingually deaf
adults who got implanted:
"1.
The acoustic "reversed frequency" perception may be difficult
for deaf people who feel totally comfortable with hearing aids that
produce amplified low-pitched sounds. With CI, they have to learn to get
used to rustling of papers and clothes, breathing, sighs, squeaky
sounds, etc.
"2.
CI doesn't amplify sounds at all so to many prelingually deaf adults,
they often experience "non-auditory percept" meaning that they
feel something in their heads and they don't feel like they're
"hearing" like they do with their HAs. Most postlingually deaf
adults who got implanted reported that CI is more like normal hearing
than their HAs.
"3.
CI sounds are several times sharper and crisper than hearing aid sounds
so they're not used to hearing ultra crisp sounds. Some felt like they
were "shocked" because the sounds are too 'sharp'."
~~~~~~~~~~~~~~~~~~~
June 2001
It's becoming pretty well accepted within the hearing loss community
that cochlear implants (CIs) can greatly improve the quality of life for
people who are post-lingually deaf, i.e. who became deaf after acquiring
language. The studies further indicate that people who have been deaf a
shorter period of time and those who continue to process auditory input
(e.g., using a hearing aid) generally tend to receive benefit faster
than those who don't.
But what about people who are congenitally deaf, i.e., who were born
deaf and have never heard or expressed spoken language. What is their
experience with CIs?
The medical industry has generally been reluctant to implant
congenitally deaf people, because early trials were not very successful.
While congenitally deaf people quickly perceive and respond to sound,
they were generally unable to understand spoken language. This is hardly
surprising, never having heard it before! But these results and other
factors led the medical industry to adopt much stricter criteria for
implanting congenitally deaf people, compared to those who are post-lingually deaf.
A recent study entitled "Delayed Implantation of Congenitally
Deaf Children and Adults" indicates that the criteria for
implanting congenitally deaf people should be reexamined. The study was
conducted by Susan B. Waltzman, PhD, J. Thomas Roland, Jr., MD, and Noel
Cohen, MD, all from the Department of Otolaryngology at the New York
University School of Medicine. They presented their results at the May
13 meeting of the American Neurotology Society.
The study focused on congenitally deaf adults and children implanted
after the age of eight. Standard audiological tests were conducted prior
to and after implantation. The majority of adults showed improvement in
monosyllabic word identification, open set sentence recognition, and
hearing in the presence of noise. All used their CIs on a regular basis,
and all believed that their CIs enhanced their communication skills. The
children also demonstrated significant improvement on a variety of
audiological tests, and the younger the child at implantation, the
greater the improvement.
Based upon these results, the researchers suggest the following
conclusions:
1. Congenitally, long-termed profoundly hearing impaired children and
adults can obtain substantial open set speech recognition after
implantation using the currently available speech processing strategies.
2. There is a correlation between the age at implantation (and age of
deafness) and the length of time the device was used with post-implant
improvement.
3. A consistent increase in mean test scores demonstrates continued
improvement in speech perceptual skills, but there is no evidence to
assert that pre-implant performance predicts benefit from cochlear
implantation.
~~~~~~~~~~~~~~~~~~~
December 2005
From the "ASHA Leader" - "Growing up
deaf, it took years for 16-year-old Mila O'Bryant to make a decision to
get a cochlear implant, and she was ecstatic to be considered a
candidate. But in an era when insurance reimbursement for cochlear
implantation is routine, a stunning insurance denial threatened to
silence her dreams. In a routine call to her primary care physician,
Mila O'Bryant's mother Kathy O'Bryant requested a series of referrals
required by their managed health care plan to complete the cochlear
implant candidacy process beyond the initial consultation and
audiological testing at Oregon Health & Science University (OHSU).
But instead of a referral, Mila O'Bryant was denied a cochlear implant
because she is prelingually deaf."
Full
Story
~~~~~~~~~~~~~~~~~
December 2007
Objectives: To evaluate sound and speech
perception and quality of life in prelingually deafened adults implanted
with state of the art devices. To investigate which patient factors
influence postoperative performance.
Study Design: Prospective intervention study.
Methods: Eight prelingually deafened subjects
(with onset of severe hearing impairment before the age of 4 years and
functioning in an oral-aural setting) participated in this study. Subjects
were implanted at a mean age of 36 (range, 21-55) years with a CII or 90 K
cochlear implant (Advanced Bionics Corp.). All subjects completed standard
speech perception tests as well as quality of life measures (Health
Utility Index Mark-II, Nijmegen Cochlear Implant Questionnaire, visual
analogue scale for subject's hearing and health) at different points in
time. Postoperative scores were compared with each other and with the
baseline preoperative scores. The relationship between nine patient
variables and the postoperative consonant-vowel-consonant (CVC) phoneme
score was also investigated.
Results: Significant improvement was measured for
CVC word and phoneme scores and several quality of life measures.
Postoperative speech perception correlated with a new and promising factor
named quality of a patient's own speech production (QoSP).
Conclusion: With state of the art implants, speech
perception and quality of life do improve in prelingually deafened adults.
More importantly, the prognostic value of QoSP should be investigated
further. Full
Story
