Download What is a Middle Ear Implant? - Guy`s and St Thomas` NHS

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Auditory Implant Programme
The Middle Ear Implant (MEI)
Information for Referrers
Who will benefit from a Middle Ear Implant?
A middle ear implant is offered to individuals who present with a hearing loss but who are
unable to manage with conventional hearing aids. A patient can present with a stable
sensorineural hearing loss or have a conductive or mixed hearing loss. Some of the
medical issues that present can be:
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Chronic otitis externa
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Eczema of the ear
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Psoriasis
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Allergies
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Absence of a pinna
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Partial or complete stenosis of the ear canal
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Exostoses (external ear bone growth closing the ear canal)
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Furunculosis
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Excessive wax production or perspiration which affect hearing aid usage
The selection process will be cautious to prevent unsuccessful implantations and
dissatisfied patients.
What is a Middle Ear Implant?
A middle ear implant is a medical prosthesis that is implanted in the middle ear and
mechanically vibrates the middle ear structures.
The Med-El Vibrant Soundbridge (VSB) middle ear implant is the device most used at
our clinic hence will be discussed in detail.
What are the referral criteria for the VSB Middle Ear Implant?
There are two patient groups who can benefit from the Middle Ear Implant
The VSB is used in the first group to treat adults with mild to severe sensorineural hearing
loss and have the following criteria:
 Mild to severe sensorineural hearing loss within the specified shaded range (see
picture below)
 Air Bone gap <10dB
 Non-progressive hearing loss
 Patient unable to wear conventional hearing aids
 Speech understanding score of 50% or better on recorded monosyllabic word test
- at 65 dBSPL in freefield using hearing aids
- at the Most Comfortable Listening (MCL) level with headphones
 Normal middle ear anatomy and function as shown by audiometric, tympanometry,
acoustic reflexes test results
 Absence of retrocochlear or central involvement
 No skin conditions preventing the attachment of the external Audio Processor to the
head.
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What is the Fitting Range of the Med-EL Vibrant Soundbridge (VSB)?
Below is the fitting range for patient with a sensorineural hearing loss
Note: The above figure is from the Med-El web site at:
www.medel.com
The VSB can also be used to treat adults with conductive and mixed hearing losses.
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Bone conduction thresholds within the shaded range (see picture below)
Absence of active middle ear infection and/or chronic fluid in the ear
Stable bone conduction thresholds
Ear anatomy allowing position of the FMT in contact with a suitable vibratory
structure of the ear
Absence of retrocochlear or central involvement
No skin conditions preventing the attachment of the external Audio Processor to the
head.
What is the Fitting Range of the Med-EL Vibrant Soundbridge (VSB)?
Below is the fitting range for patient with a conductive and mixed hearing loss
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The fitting ranges differ for both groups as does the placement of the
implant within the middle ear space.
What are the parts of the Med-El Vibrant SoundBridge implant?
The middle ear implant system consists of 2 main components: an internal and an external
part.
The External Part is called the Audio Processor. It contains the microphone, battery, a
digital signal processor, etc. It is held in place to the head with a magnet. The Audio
Processor picks up sound from the environment, filters the sound into coded signals and
then transmits the signal across the skin to the implanted receiver.
The Internal Part is implanted during the surgical procedure. It consists of an internal coil,
a magnet to hold the Audio Processor over the implant, a demodulator, the conductor link,
the Vibrating Ossicular Prosthesis (VORP) and Floating Mass Transducer™ (FMT™)
which is attached to the ossicle. For patients with a conductive and mixed hearing loss the
FMT is placed into the Round Window niche. The FMT is a tiny electromagnetic
transducer that mechanically vibrates the ossicles by mimicking the natural motion of the
ossicular chain, thereby delivering the signal to the fluid-filled cochlea.
Note: This figure is taken from the
Med-El website at:
www.medel.com/english/30_Produ
cts/VibrantSoundbridge/index.php
What are the outcomes of the Middle Ear Implant?
A middle ear implant does not restore normal hearing and requires time to acclimatize to
the sound quality. The degree of benefit varies with each individual. Variables influencing
the benefits each person will derive include factors such as age, degree and duration of
hearing loss and integrity of the auditory system. The advantages of having a MEI are
more natural sound quality, lack of feedback, absence of occlusion and distortion, and
favorable cosmetic appearance.
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What is the patient management pathway?
The expected length of assessment from referral to the final consent appointment is
typically 18 weeks, although the assessment may be extended for many reasons,
including patient request or medical reasons. Following the assessment the patient will
either be listed for surgery or discharged from the clinic. The results of tests will be
explained as the assessment progresses. On completion of the assessment a team report
will be sent to the referrer as well as the other professionals you have asked us to inform.
Initial Screening Appointment
The initial meeting with Audiological Scientist who will:
 Explain the assessment process
 Take a detailed case history.
 Discuss the middle ear implant and issues surrounding implantation, expectations
and potential outcomes.
 Conduct some audiological testing
If the patient is suitable to continue then s/he will undergo a full assessment:
Further Audiological Assessments
 Further clinic appointments will be issued to assess your hearing, amplification
needs, and functional aided hearing abilities. The number of appointments required
will vary but will typically include the following.
 Hearing Aid Fitting - to optimize your hearing aid setting
 Auditory Brainstem Response Test – an objective, non-invasive hearing test
 Speech Perception tests
 Pre-operative Questionnaires
Each patient’s management plan is discussed and reviewed at the monthly multidisciplinary team meeting.
Medical Assessment
The meeting with the ENT surgeon will involve discussion regarding:
 Medical history
 Decisions made regarding further assessments required.
 Magnetic Resonance Imaging (MRI) and possibly Computer Tomography (CT) may
be discussed and booked to check the integrity of the cochleae and hearing nerves.
Final ENT Consultation
The final appointment with the surgeon will involve discussion of:
 Medical issues surrounding the middle ear implant surgery
 Surgical risks and side effects (temporary taste disturbance, tinnitus, dizziness,
balance impairment, infection, device failure, etc.)
 Surgical consent
Once consent is signed the patient will be offered an operation slot within 8 weeks. The
device will then be activated about 8 weeks after surgery.
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What can be expected of the Surgical Experience?
The patient will undergo pre-admission check prior to the operation to confirm your fitness
for the surgery. The operation will take place at Guy’s Hospital - either on a Thursday or
Friday. The patient may be admitted the night before the operation or the morning to
Blundell Ward. The surgery takes approximately 2-3 hours. The surgery is done under
general anaesthetic. A back-up device is always available during the operation. A pressure
bandage will be applied around the patient’s head after the operation. S/He will be
discharged the day after the operation if no complications. S/He will be given contact
numbers for the ENT doctor on call and informed to not wash his/her hair till s/he is seen
by the ENT doctor 10 days after the surgery. The device will be activated at 8 weeks after
the surgery.
What ongoing support can the patient expect following surgery?
The following is an outline of the contact with the team following implantation. The patient
can contact the department at any stage should s/he have any questions or concerns.
TIMELINE
Surgery
10 days after surgery
8 weeks after surgery
12 weeks after surgery
(4 weeks after the device activation)
TEAM CONTACT
 Guys Hospital
 ENT Consultation – St Thomas’ Hospital
 Audiological testing
 Activation of the middle ear implant
 Audio Processor fine tuning
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20 weeks after surgery
(12 weeks after device activation
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Audiological testing including Speech
Perception Tests
Post Operative Questionnaires
Annual follow-up (as required)
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Audiological testing
Device check-up
Further Sources of Information
Additional information regarding Middle Ear Implants can be found on the following
websites:
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MEDEL
www.medel.com
http://www.medel.com/english/30_Products/VibrantSoundbridge/index.php
How can I contact the department?
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Reception
(T) 020 7188 6245
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Administration
(T) 020 7188 2197
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Fax
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For an appointment e-mail [email protected]
020 7188 2192
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To request for repairs and spares e-mail: [email protected]
[email protected] (to email individual team members)
Who are the Team Members?
The team is made up of a dedicated multi-disciplinary group of professionals, which
includes:
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Consultant ENT Surgeons: Mr Alec Fitzgerald O’Connor, Mr Dan Jiang
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Audiological Scientists: Mr Terry Nunn, Ms Jennifer Demler, Ms Catherine
Kelleher, Ms Arveni Dooki, Ms Sheena Mclaren, Ms Elaine Burke
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Hearing Therapist: Karen Archer
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Speech and Language Therapists: Ms Sandra Driver, Ms Emma Stark,
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Administrators: Ms Susie Altham, Ms Melika Emmanuel, Ms Sandra Allen
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ENT Nurses: Carol Kimberlin, Ramon Gamab
Further information
If you have any questions please contact the Auditory Implant Programme on:
Phone 0207 188 6245, Fax 0207 188 2192, e-mail AIAdmin @gstt.nhs.uk.
PALS - To make comments or raise concerns about the Trust’s services, please contact
our Patient Advice and Liaison Service (PALS). Ask a member of staff to direct you to
PALS or:
t: 020 7188 8801 at St Thomas’ t: 020 7188 8803 at Guy’s e: [email protected]
Knowledge & Information Centre (KIC) - For more information about health conditions,
support groups and local services, or to search the internet and send emails, please visit
the KIC on the Ground Floor, North Wing, St Thomas’ Hospital.
t: 020 7188 3416 e: [email protected]
Language support services - If you need an interpreter or information about the care you
are receiving in the language or format of your choice, please get in touch using the
following contact details.
t: 020 7188 8815 fax: 020 7188 5953 e: [email protected]
NHS Direct - Offers health information and advice from specially trained nurses over the
phone 24 hours a day.
t: 0845 4647 w: www.nhsdirect.nhs.uk
Guy’s and St Thomas’ NHS Foundation Trust
St Thomas’ Hospital, Westminster Bridge Road, London SE1 7EH Guy’s Hospital, Great Maze Pond, London SE1 9RT
Switchboard: 020 7188 7188
www.guysandstthomas.nhs.uk
© 2010 GUY’S AND ST THOMAS’ NHS FOUNDATION TRUST. ALL RIGHTS RESERVED.
Published February 2010