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July 2012
J-J-J-July Jitters
Yes, it is still icy cold and yes, we
still can’t get over it. Welcome to
another chilly e-zine...chilly due to
our current climate and not because of our content of course.
With the schools starting up again
we’ve initiated our thaw-phase
from our winter holiday lethargy
and moving into higher gears to
change the world one patient at a
time.
City. The Speech-Language Therapy
program will include 8 distinguished researchers from the International Association of Logopedics and Phoniatrics (IALP) that will
be presenting a series of lectures
on Motor Speech Disorders in
adults and children. Visit
www. ialp. info/motor -speechdisorders-committee-pg16135.html
for more information. The Audiology
program will have Prof.Larry
Humes from the University of
Indiana as keynote speaker this
year. Dr. Humes is an expert in
auditory perception, with an special interest in the effects of
hearing impairment and aging on
auditory perception. Visit the
congress website for more information as well as registration
forms .
Blessings for the week.
INSIDE THIS
ISSUE:
Word of welcome
1
Academic Corner: HIV and
1
Hearing Loss
TECH Talk:
3
More on i-Pads
New Middle
5
Ear Microphone gets
research attention
Fun Facts
6
Contact your
Counsel
6
With the year going at the speed of
light we are also speedily approaching the 2012 SASLHA/SAAA/
ENT Conference which will be held
from 3-6 November 2012 at Sun
Enjoy the e-zine.
Dirk Lourens &
Cara Hollander
Editors: E-zine
Hang on guys. We’ll beat the freeze!
Academic Corner: Children Exposed to HIV in the Womb at
Increased Risk for Hearing Loss
Children exposed to HIV in
the womb may be more likely to experience hearing loss
by age 16 than are their unexposed peers, according to
scientists in a National Institutes of Health research network.
The researchers estimated
that hearing loss affects 9 to
15 percent of HIV-infected
children and 5 to 8 percent
of children who did not have
HIV at birth but whose mothers had HIV infection during
pregnancy. Study participants ranged from 7 to 16
years old.
The researchers defined
hearing loss as the level at
which sounds could be detected, when averaged over
four frequencies important
for speech understanding
(500, 1000, 2000, and 4000
Hertz), that was 20 decibels
or higher than the normal
hearing level for adolescents
or young adults in either ear.
"Children exposed to HIV
before birth are at higher
risk for hearing difficulty, and
it's
important
for
them―and the health providers
who
care
for
them―to be aware of this,"
said George K. Siberry,
M.D., of the Pediatric, Adolescent, and Maternal AIDS
Branch of the Eunice Kennedy Shriver National Institute of Child Health and
Human
Development
(NICHD), the NIH institute
that leads the research
network.
The study was published
online in The Pediatric Infectious Disease Journal.
Compared to national averages for other children their
Continued on pg. 2
PAGE
2
age, children with HIV infection
were about 200 to 300 percent
more likely to have a hearing loss.
Children whose mothers had HIV
during pregnancy but who themselves were born without HIV
were 20 percent more likely than
to have hearing loss.
More than 200 children and teenagers participated in this study
conducted as part of the Pediatric
HIV/AIDS Cohort Study network,
led by NICHD. All had been exposed to HIV before birth, and
about 60 percent were HIVpositive at the time of the study.
Researchers conducted hearing
tests on the children if their par-
Continued from pg 1
ents or caregivers had reported
hearing problems, they had low
scores on a standard test of language or their health care providers detected hearing problems
during standard hearing screenings.
The researchers classified participants who could not hear tones
below a certain volume as having
hearing loss with difficulties in
quiet and noisy settings. The researchers documented a greater
proportion of hearing loss cases
among HIV-positive children and
found that those who had developed AIDS at any point were
even more likely to have hearing
loss -- even if the disease was
under control at the time of the
study.
Earlier studies have found that
children with HIV are susceptible to middle ear infections. Repeated middle ear infections can
cause hearing loss. However, in
60 percent of cases in the study,
hearing loss was the result of
problems with the transmission
of sound from the nerves of the
ear to the brain, rather than to
damage in the middle ear resulting from ear infections.
www.sciencedaily.com/
releases/2012/06/12
PAGE
TECH TALK: iPad Technology in Speech Therapy
After receiving some very positive responses to our previous TECH article about practical ways of using i-Pads as a therapy modality, we decided to investigate and share some more resources in this continuously expanding therapy tool. We visited http://communicationtherapy.wordpress.com/2011/02/27/ipadtechnology-in-speech-therapy-overview/ and came across the Communication Therapy Blog which offers
insight, resources and guidance in rems of i-Pad use in Speech-Language Therapy. We have included
an excerpt from the site to wet your appetite...
3
PAGE
4
SPEECH THERAPY POSITION: Pretoria, Gauteng
The Baby Therapy Centre in Pretoria requires a part time Speech- Language Therapist (15 hours per week).
The candidate must be fluent in both English and Afrikaans and have 1-2 years experience handling babies
and toddlers under the age of three years.
Must be able to work independently and as part of a therapy team with a transdisciplinary and interdisciplinary approach.
Evidence in the Field of Communication Pathology
Tuesday 7 August 2012
EVIDENCE in the field of COMMUNICATION PATHOLOGY: half-day course on 7 AUGUST 2012 at Department of Communication Pathology in TUKS - 5 CPD points
Register now !!!
Presented by
PROF DR EDWIN MAAS,
Department of Speech, Language and Hearing Science
University of Arizona
Organised by
Department of Communication Pathology
(University of Pretoria)
Course Coordinator:
Nathalie van Waeyenberge
E-mail: [email protected]
RESTORING HEARING WITH DISCRETE DEVICE: A MIDDLE-EAR MICROPHONE FOR
MORE CONVENIENT COCHLEAR IMPLANTS
ScienceDaily (Apr. 30, 2012) — Cochlear implants have restored basic hearing
to some 220,000 deaf people, yet a
microphone and related electronics
must be worn outside the head, raising
reliability issues, preventing patients
from swimming and creating social stigma. Now, a University of Utah engineer
and colleagues in Ohio have developed
a tiny prototype microphone that can be
implanted in the middle ear to avoid
such problems.
The proof-of-concept device has been
successfully tested in the ear canals of
four cadavers, the researchers report in
a study just published online in the Institute of Electrical and Electronics Engineers journal Transactions on Biomedical Engineering.
The prototype -- about the size of an
eraser on a pencil -- must be reduced in
size and improved in its ability to detect
quieter, low-pitched sounds, so tests in
people are about three years away,
says the study's senior author, Darrin J.
Young, an associate professor of electrical and computer engineering at the
University of Utah and USTAR, the Utah
Science Technology and Research initiative.
The study showed incoming sound is
transmitted most efficiently to the microphone if surgeons first remove the incus
or anvil -- one of three, small, middleear bones. U.S. Food and Drug Administration approval would be needed for
an implant requiring such surgery.
The current prototype of the packaged,
middle-ear microphone measures 2.5by-6.2 millimeters (roughly one-tenth by
one-quarter inch) and weighs 25 milligrams, or less than a thousandth of an
ounce. Young wants to reduce the package to 2-by-2 millimeters.
Problems with External Parts on
Cochlear Implants
The National Institutes of Health says
almost 220,000 people worldwide with
profound deafness or severe hearing
impairment have received cochlear implants, about one-third of them in the
United States, where two-fifths of the
recipients are children.
In conventional cochlear implant, there
are three main parts that are worn externally on the head behind the ear. Implanted under the skin behind the ear
are a receiver and stimulator to convert
the sound signals into electric impulses,
which then go through a cable to between four and 16 electrodes that wind
through the cochlea of the inner ear and
stimulate auditory nerves so the patient
can hear.
"It's a disadvantage having all these
things attached to the outside" of the
head, Young says. "Imagine a child
wearing a microphone behind the ear. It
causes problems for a lot of activities.
Swimming is the main issue. And it's not
convenient to wear these things if they
have to wear a helmet."
Young adds that "for adults, it's social
perception. Wearing this thing indicates
you are somewhat handicapped and that
actually prevents quite a percentage of
candidates from getting the implant.
They worry about the negative image."
As for reliability, "if you have wires connected from the microphone to the coil,
those wires can break," he says.
How Sound Moves in normal ears,
Cochlear Implants and the new device
Sound normally moves into the ear canal
and makes the eardrum vibrate. The
stapes or stirrup touches the cochlea.
Hair cells on the cochlea's inner membrane move, triggering the release of a
neurotransmitter chemical that carries
the sound signals to the brain.
In profoundly deaf people who are candidates for cochlear implants, the hair cells
don't work for a variety of reasons, including birth defects, side effects of
drugs, exposure to excessively loud
sounds or infection by certain viruses.
In a cochlear implant, the microphone,
signal processor and transmitter coil
worn outside the head send signals to
the internal receiver-stimulator, which is
implanted in bone under the skin and
sends the signals to the electrodes implanted in the cochlea to stimulate auditory nerves. The ear canal, eardrum and
hearing bones are bypassed.
The system developed by Young implants all the external components.
Sound moves through the ear canal to
the eardrum, which vibrates as it does
normally. But at the umbo, a sensor
known as an accelerometer is attached
to detect the vibration. The sensor also is
attached to a chip, and together they
serve as a microphone that picks up the
sound vibrations and converts them into
electrical signals sent to the electrodes in
the cochlea.
The device still would require patients to
wear a charger behind the ear while
sleeping at night to recharge an implanted battery. Young says he expects the
battery would last one to several days
between charging.
Young says the microphone also might
be part of an implanted hearing aid that
could replace conventional hearing aids
for a certain class of patients who have
degraded hearing bones unable to adequately convey sounds from conventional hearing aids.
Testing the Microphone in Cadavers
Conventional microphones include a membrane or diaphragm that moves and generates an electrical signal change in response to sound. But they require a hole
through which sound must enter -- a hole
that would get clogged by growing tissue if
implanted. So Young's middle-ear microphone instead uses an accelerometer -- a
2.5-microgram mass attached to a spring - that would be placed in a sealed package
with a low-power silicon chip to convert
sound vibrations to outgoing electrical
signals.
The package is glued to the umbo so the
accelerometer vibrates in response to eardrum vibrations. The moving mass generates an electrical signal that is amplified by
the chip, which then connects to the conventional parts of a cochlear implant: a
speech processor and stimulator wired to
the electrodes in the cochlea.
"Everything is the same as a conventional
cochlear implant, except we use an implantable microphone that uses the vibration of the bone," Young says.
To test the new microphone, the researchers used the temporal bones -- bones at
the side of the skull -- and related ear canal, eardrum and hearing bones from four
cadaver donors.
The researchers inserted tubing with a
small loudspeaker into the ear canal and
generated tones of various frequencies
and loudness. As the sounds were picked
up by the implanted microphone, the researchers used a laser device to measure
the vibrations of the tiny ear bones. They
found the umbo -- where the eardrum connects to the hammer or malleus -- produced the greatest sound vibration, particularly if the incus or anvil bone first was
removed surgically.
The experiments showed that when the
prototype microphone unit was attached to
the umbo, it could pick up medium pitches
at conversational volumes, but had trouble
detecting quieter, low-frequency sounds.
Young plans to improve the microphone to
pick up quieter, deeper, very low pitches.
In the tests, the output of the microphone
went to speakers; in a real person, it would
send sound to the implanted speech processor. To demonstrate the microphone,
Young also used it to record the start of
Beethoven's Ninth Symphony while implanted in a cadaver ear. It is easily recognizable, even if somewhat fuzzy and muffled.
"The muffling can be filtered out," says
Young.
Example of the middle ear mic.
2012 National Council Contact Details
DESIGNATION
NAME
EMAIL ADDRESS
President
Vice-President
Treasurer
Cathy Pringle
Dirk Lourens
Cornel du Preez
[email protected]
[email protected]
[email protected]
Professional Liaison Officer
Jane Herbert
[email protected]
Office Manager
Claudine Emmerick
[email protected]
Ethics and Standards Chair
Prof Development Officer
SAJCD Editor in Chief
Susan Swart
Anita Edwards
Janan Dietrich
[email protected]
[email protected]
[email protected]
CPD
University Alliance
Communiphon Editor
Academic Conference Program Co-ordinator
Anita Edwards
Sandra du Plessis
Cara Hollander
Dr.Anna-Marie Olivier
[email protected]
[email protected]
[email protected]
[email protected]
Coding Chairperson
Alison Dent
[email protected]
PR and Marketing Chairperson
Nicole de Rocha
[email protected]
Zone One Representative
Dr.Priya Rajaram
[email protected]
Zone Two Representative
Erica Bostock
[email protected]
Zone Three Representative
Ingrid von Bentheim
[email protected]
Zone Four Representative
Anneline Jack
[email protected]
SASLHA OFFICE DETAILS
OFFICE MANAGER: Mrs Claudine Emmerick
OFFICE HOURS: Mondays - Fridays 8h00 - 15h00
(During School Holidays: Mondays – Fridays 07h00 -14h00)
POSTAL ADDRESS: PO Box 10813, Linton Grange, 6015 Port Elizabeth
LOCAL TEL: 0861 113 297
INT TEL: +27 (0)41 3794253
FAX: +27 (0)41 3795388
EMAIL: [email protected]