Otodynamics Otocheck ABR User manual

Otocheck ABR
Issue 4
Otocheck ABR
User Manual

CHAPTER ONE
Introduction
2
Introduction
User Manual for
Otocheck ABR
Issue 4 : May 2017
Firmware Revision 3.26.1.16 onwards
Doc Ref: MANABR4-4
Copyright Notice
No part of this publication may be copied by any means,
translated or distributed to third parties without the express
written permission of Otodynamics Ltd.
Copyright © 2017 Otodynamics Ltd. All Rights Reserved.
Otodynamics Ltd
30-38 Beaconseld Rd
Hateld Herts AL10 8BB UK
0120

Otocheck ABR
User Manual
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Introduction
Contents
1Introduction 7
1.1 Intended Use 7
1.2 General guidance 7
1.3 General use precautions 8
1.4 Auditory Brainstem Response 10
2 Equipment identication 11
2.1 Supplied in Otocheck ABR kit 11
2.2 Optional accessories 15
2.3 Controls, indicators and connections 16
2.4 Labelling 17
3Getting started 19
3.1 Connecting probes and electrodes 19
3.2 Initial charge 22
3.3 Using the keys and keypad 22
4Switching On 26
4.1 Switch on screen 26
4.2 Logo screen 27
4.3 Login 28
4.4 Main menu 29
5Test preparation 30
5.1 General checks before testing 30
5.2 Environment checks 30
5.3 Tip selection and probe tting 31
5.4 Electrode tting 33

CHAPTER ONE
Introduction
4
Introduction
6ABR test problems 36
6.1 Impedance values are too high and the test will not run 36
6.2 High myogenic activity/artefact reject 37
6.3 High environment electrical noise 38
6.4 No response in ear with known normal hearing 38
7ABR test 39
7.1 Impedance check 40
7.2 Checkt 44
7.3 Ear cup Checkt 46
7.4 ABR test 47
7.5 Quick Save option 54
7.6 Review 55
7.7 Save 56
8Worklist 59
8.1 Adding Patients 59
8.2 Testing from the Worklist 60
8.3 Editing details 60
8.4 Deleting patients 61
9Records 62
9.1 Patient list 63
10 Conguration 66
10.1 Conguration menu 66
10.2 Quality tests 67
10.3 Test settings 67
10.4 Date and time 74
10.5 System 75
10.6 Users 81

Otocheck ABR
User Manual
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Introduction
11 Printing and downloading 84
11.1 Bluetooth wireless printing and download 84
11.2 Wired downloading 85
11.3 When you can print and download 86
11.4 The printing process 89
11.5 Printer fault detection 91
11.6 Printer light summary 91
11.7 Paper 92
11.8 Charging the printer 93
11.9 Changing the battery 94
12 Scanning 95
12.1 Scanning facility 95
12.2 Scanner types 95
12.3 When to use the scanners 97
13 Quality tests 99
13.1 Probe test 99
13.2 ABR cable test 104
13.3 ABR cavity test 105
14 Probe, tips and accessories 106
14.1 Probe and service accessories 106
14.2 Probe cable clip 106
14.3 Probe tips 108
15 Probe care 110
15.1 Cleaning 110
15.2 Changing probe coupler tubes 110
15.3 Probes safety note 112
16 Care of the Otocheck 113
16.1 Use of the Otocheck and cleaning 113

CHAPTER ONE
Introduction
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Introduction
17 Power 115
17.1 Battery life 115
17.2 Initial charge 115
17.3 Standby 116
17.4 Battery charge 117
17.5 Charging the Otocheck 119
17.6 Conditioning the Otocheck battery 122
17.7 Additional battery care 123
18 Equipment troubleshooting 124
18.1 Otocheck lock-up 124
18.2 Switch on 124
18.3 System details 124
18.4 Instrument fault message 125
18.5 Hardware fault messages 126
19 Training 127
20 Obtaining service 128
21 Calibration 129
22 Mode of operation 130
22.1 ABR test 130
23 Technical specications 136
23.1 Otocheck ABR 136
23.2 Electromagnetic Compatibility: Otocheck ABR 140
23.3 EN60645-3 conformance notes 146
23.4 Symbol explanations 148
24 Index 150

Otocheck ABR
User Manual
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Introduction
1Introduction
1.1 Intended Use
This Otodynamics Otocheck ABR device is indicated for use when there is
a requirement to screen for hearing disorders by objective and non-invasive
means. ABR screening test results are automatically interpreted and a
clear ‘Pass’ or ‘Refer’ result is presented to the user who will be a trained
screener, audiologist or medical professional. Use of the device is indicated
when the patient is unable to give reliable voluntary responses to sound,
especially with infants. Use of the device facilitates the early detection of
hearing loss and its characterization.
1.2 General guidance
Each test type provides evidence of normal peripheral hearing function
objectively and non-invasively.
The screening functions of this instrument are especially suitable for
use with infants. The ABR screening function uses conventional Fsp
methodology to detect the response supported by waveform identication
(Template Correlation) which is optimised for infants from 34 weeks to
6 months gestational age. Template-free pass criteria for ABR may be
selected for use with patients outside this age range (see chapter 10
Conguration, section 10.3.4 Pass criteria).
The device can be used in a wide range of di󰀨erent environments for
example in the well-baby nursery, the NICU, a doctor’s o󰀩ce, an audiology
clinic, the outpatient clinic or in the home. For optimum results and short
test times the room should be quiet and the patient should be very quiet
and still during the test. The device will clearly indicate levels of acoustic
noise and electrical interference. Use this as a guide to improve the testing
environment.
The screening functions of the device are intuitive and suitable for
operation by trained screeners without specialized knowledge. Testing and
interpretation is automated.

CHAPTER ONE
Introduction
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Introduction
1.3 General use precautions
Do not connect the patient to high frequency (HF) surgical equipment
and to an Otocheck in ABR mode simultaneously. Failure to observe this
precaution may result in burns at the site of the electrodes and possible
damage to the Otocheck.
When one or more ABR electrodes are connected to the patient take care
to avoid any contact between the remaining electrodes and conductive
surfaces, such as other equipment. Failure to observe this precaution my
result in harmful electrical currents owing through the patient.
The Otocheck pass criteria are set in the Conguration area (see chapter
10 Conguration). It is the responsibility of the user to ensure that the
pass criteria set meet their requirements.
Measuring ABRs requires that the ear is exposed to sound. Whilst the
level of this exposure is harmless under normal test conditions, it is not
recommended that tests be allowed to continue indenitely even if there is
no result.
The Otocheck includes ‘stop criteria’ which will automatically terminate the
test when an ABR pass has been achieved or after ve minutes.
Whilst this limits the sound exposure in a single test, the user is responsible
for limiting the number of separate tests performed on the same ear.
The Otocheck has built in signal analysis proven to distinguish true ABRs
from artefactal signals. Checks should be performed weekly and before
each test session to conrm the system continues to operate e󰀨ectively
(see chapter 13 Quality tests).
In exceptional circumstances, either an equipment fault or failure to comply
fully with the instructions in this manual may result in unreliable test results.
The probe’s coupler tubes which carry sound to and from the ear canal
are protected from contamination by the disposable tip. The probe should
never be inserted into the ear without a disposable tip attached. Doing so
risks damage to the ear by the probe body and contamination of the probe
by the ear.
TRAINING
REQUIRED

Otocheck ABR
User Manual
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Introduction
If contamination occurs the coupler tubes must be replaced (see 15.2
Changing probe coupler tubes).
Visually inspect the coupler tubes before use. A blocked sound delivery
tube may prevent the Otocheck from achieving its target stimulation
level and so prevent testing. A blocked microphone tube will prevent
the Otocheck from sensing the stimulus level in the ear. As a result the
Otocheck may apply a louder than normal sound to the ear.
All surfaces of the Otocheck may be cleaned with an alcohol based wipe or
cloth with antiseptic uid. Dry the device immediately with tissue.
Do not allow liquid to enter the instrument.
If additional hygienic protection is required, clear plastic infection control
sleeves designed to contain the Otocheck during use are available from
Otodynamics.

CHAPTER ONE
Introduction
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Introduction
1.4 Auditory Brainstem Response
Auditory Brainstem Response (ABR) is an electrophysiological response
that measures the auditory system’s response to sound. Three voltage
sensors (electrodes) are placed on the patient and a sound probe is placed
in the test ear. The equipment sends a click, brief tone, or chirp sound
stimuli to the test ear.
The cochlea (inner ear) converts sound into electrical signal. These signals
travel in sequence to the acoustic nerve, the brainstem, and nally to
the cortical areas of the brain. The electrodes pick up these electrical
responses to the sound which are commonly known as auditory evoked
potentials. A response which occurs within 20ms of the onset of the
stimulus is referred to as an Auditory Brainstem Responses (ABR).
As the amplitude of the ABR is very small compared to the ‘noise’ of other
brain electrical activity (EEG) the ‘signal to noise ratio’ is very poor. It is
enhanced by a process called averaging. The amplitude of the ABR is also
quite small compared to voltages generated by myogenic (muscle) activity;
therefore, ideally, patients should be tested when sleeping or when very
still.
If EEG and myogenic artefacts are below a tolerable (noise reject) level,
the Otocheck ABR rmware will detect the ABR and automatically give a
simple Pass/Fail response to the user. Other details of the test including
the ABR waveforms may also be viewed, and results interpreted, manually
if so desired.