MADSEN Capella and the OTOsuite Otoacoustic Emissions module Reference Manual Rev 04

Copyrightnotice The manufacturer authorizes GN Otometrics A/S to publish manuals approved and released by the manufacturer. No part of this documentation orprogram may be reproduced, stored in a retrieval system, ortransmitted, in any form orby any means, electronic, mechanical, photocopying, recording,or otherwise,without the prior written consent of GN Otometrics A/S. Copyright© 2015, GN Otometrics A/S Published in Denmark byGN Otometrics A/S, Denmark All information, illustrations, and specifications in this manual are based on the latest productinformation available at the time of publication. GN Otometrics A/Sreserves the right to make changes at any time without notice. Versionrelease date 2015-02-02 Technicalsupport Please contact your supplier.

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Table of Contents 1

Introduction to MADSEN Capella 1.1 Intended Use 1.2 Data Acquisition Board 1.3 The OTOsuite Otoacoustic Emissions module 1.3.1 NOAH 1.4 About this Manual 1.4.1 Installation and Assembly 1.4.2 Safety 1.4.3 Training 1.5 Typographical conventions 1.5.1 Navigation

5 5 5 5 5 6 6 6 6 6 7

2

Unpacking and Installing Capella and the Otoacoustic Emissions Module 2.1 Unpacking 2.1.1 Storage, Handling and Transportation 2.2 Assembling Capella 2.2.1 Front and top views of Capella 2.2.2 Connecting Capella to the PC and probe 2.2.3 Switching off Capella 2.3 ER-10D OAE Probe 2.3.1 Probe tip replacement 2.4 Foam Eartips 2.5 Plastic Eartips

9 9 9 9 9 10 10 11 11 12 12

3

Preparing for testing 3.1 Using an ER-10D probe

15 15

4

Measuring Otoacoustic Emissions with Capella 4.1 Measuring Distortion Product OAEs 4.1.1 The DP Otoacoustic Emissions Screens 4.1.1.1 The Otoacoustic Emissions Control Panel 4.1.1.2 The results graph in DP-gram and DP I/O 4.1.1.3 The Spectrum graph 4.1.1.4 The Legend box 4.1.1.5 Overlays - DP-gram and DP I/O 4.1.1.6 Data table - DP-gram and DP I/O 4.1.2 Configuring measurement buttons in DP-gram 4.1.2.1 Setting up PrecisePoints 4.1.3 Configuring measurement buttons in DP I/O 4.1.4 Configuring acceptance criteria - DP-gram and DP I/O 4.1.5 Normative DPOAE data 4.1.5.1 Normative data values 4.1.6 Viewing historical DP data 4.2 Measuring Transient OAEs and Spontaneous OAEs 4.2.1 The TEOAE and SOAE screens 4.2.1.1 The Spectral Response graph 4.2.1.2 The Temporal Response graph 4.2.1.3 The Legend box 4.2.1.4 Overlays - TEOAE and SOAE

17 17 17 18 19 20 20 21 21 23 23 24 25 26 26 28 29 29 30 31 31 31

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4.3 4.4 4.5 4.6 4.7 4.8

4

4.2.1.5 Data table - TEOAE 4.2.1.6 Data table - SOAE 4.2.2 Configuring measurement buttons in TEOAE 4.2.3 Configuring acceptance criteria in TEOAE 4.2.4 Configuring measurement buttons in SOAE 4.2.5 About Gain Deleting stored curves, swapping data between ears and copying data Probe Fit Configuring Options Viewing OAE Graphs: Zoom and Pan Printing reports in Otoacoustic Emissions Selecting Test Types for Otoacoustic Emissions

31 32 33 33 34 34 34 35 35 39 39 39

5

Service, Maintenance and Cleaning

41

6

Troubleshooting 6.1 My Capella is not responding 6.2 The power LED on Capella is blinking 6.3 I get an error message when starting OTOsuite 6.4 There is no sound output from the OAE probe 6.5 The system does not pick up signals when testing 6.6 There is high noise in the acquired signal 6.7 An error message appears when the system starts a test 6.8 My computer freezes or Capella does not start

43 43 43 43 43 43 43 44 44

7

Safety 7.1 Definition of Symbols 7.2 Warning notes 7.3 Manufacturer 7.4 Responsibility of the manufacturer

45 45 45 46 46

8

Technical Specifications - MADSEN Capella 8.1 Standards 8.2 Operating environment 8.3 Storage environment 8.4 Electrical Specifications 8.5 PC power supply 8.6 Technical Specifications - ER-10D Probe 8.7 Technical Specifications - OAE System 8.8 Accessories 8.9 Notes on EMC (Electromagnetic Compatibility)

49 49 49 49 49 49 49 49 50 51

9

Glossary of Terms

55

Index

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1

Introduction to MADSEN Capella MADSEN Capella is a portable Otoacoustic Emission (OAE) device. You use the OTOsuite Otoacoustic Emissions module to operate Capella. Capella cannot be used without OTOsuite software. The device is powered by a standard 5V USB (Universal Serial Bus) port. Capella is connected to the computer's USB port. This connection transfers the user-defined settings to be used by Capella and returns the acquired data. The DSP board inside Capella contains a digital signal processor (DSP) for real-time processing. An OAE Amplifier is included for the use of the OTOsuite software.

1.1

Intended Use The intended use of MADSEN Capella and the OTOsuite Otoacoustic Emissions module is for the screening and diagnosis of patients using otoacoustic emission techniques. Capella, used together with the Otoacoustic Emissions module, is intended for use as an aid in diagnosing hearing related disorders, and as a tool in the evaluation of conditions which affect otoacoustic emission responses to auditory stimuli. Capella can be used for patients of all ages. It is intended for use by trained personnel in a hospital, nursery, clinic, audiologist’s office or other appropriate setting. The Otoacoustic Emissions research and diagnostic components may be used by investigators and students to evaluate the usability and effects of measured otoacoustic emissions. There are no known contraindications for the use of the device.

1.2

Data Acquisition Board The Data Acquisition Board, inside Capella, is used to acquire otoacoustic emission (OAE) signal recordings for OTOsuite. The board consists of an OAE amplifier, electrical isolation components/electronics, and a serial 16-bit A/D and D/A.

1.3

The OTOsuite Otoacoustic Emissions module The OTOsuite Otoacoustic Emissions module is designed to operate with MADSEN Capella as the test device. Capella used with the OTOsuite Otoacoustic Emissions module is a complete Distortion-Product Otoacoustic Emissions (DPOAE) acquisition and analysis system. DPOAEs are responses generated by the cochlea to a two-tone stimulation presented to the ear. DPOAEs are generated by most normal healthy ears, and can be used to evaluate cochlear function.

1.3.1

NOAH OTOsuite integrates with: •

NOAH systems

•

NOAH for ENT

•

NOAH-compatible Office Management systems.

The NOAH System is a HIMSA product for managing clients, launching hearing test applications and fitting software, and storing audiological test results. OTOsuite stores test results using NOAH.

Note • Whenever reference in this manual is made to NOAH, this reference should also apply to NOAH compatible systems..

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1 Introduction to MADSEN Capella

1.4

About this Manual This is your reference guide to installing, calibrating and using MADSEN Capella and to using the Otoacoustic Emissions module. This manual also introduces you to the key features of the device and the software, as well as to working scenarios for performing tests and viewing and printing test results.

Note • If you are using OTOsuite with NOAH, we recommend that you be familiar with the screens and functions provided in NOAH.

1.4.1

Installation and Assembly Unpacking ► 9 and Assembling Capella ► 9 contain a full description of unpacking instructions, and how to assemble the device. For instructions on installing OTOsuite, see the OTOsuite Installation Guide, which you can find on the OTOsuite installation medium (disk or memory stick).

1.4.2

Safety This manual contains information and warnings, which must be followed to ensure the safe performance of the devices and software covered by this manual. Local government rules and regulations, if applicable, should also be followed at all times. Safety information is stated where it is relevant, and general safety aspects are described in Safety ► 45.

1.4.3

Training It is recommended that you read this manual and try out test scenarios before you start operating Capella so that you are familiar with both the device and the software program before testing a patient. After you install OTOsuite, you can find OTOsuite manuals and related documentation on your PC. In the Start menu, open OTOsuite Manuals, which contains an overview with links to all manuals.

1.5

Typographical conventions The use of Warning, Caution and Note To draw your attention to information regarding safe and appropriate use of the device or software, the manual uses precautionary statements as follows:

Warning • Indicates that there is a risk of death or serious injury to the user or patient.

Caution • Indicates that there is a risk of injury to the user or patient or risk of damage to data or the device.

Note • Indicates that you should take special notice.

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1 Introduction to MADSEN Capella

1.5.1

Navigation Menus, icons and functions to select are shown in bold type, as for instance in: •

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Click the Set options icon on the toolbar or select Tools > Options...

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1 Introduction to MADSEN Capella

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2

Unpacking and Installing Capella and the Otoacoustic Emissions Module To install and get started with Capella and the OTOsuite Otoacoustic Emissions module, follow the sequence below: 1. Install OTOsuite on the PC before you connect to MADSEN Capella from the PC. For instructions on installing OTOsuite, see the OTOsuite Installation Guide, which you can find on the OTOsuite installation medium (disk or memory stick). 2. Unpack Capella (see Unpacking ► 9.) 3. Assemble Capella (see Assembling Capella ► 9) 4. Connect the cables of the test equipment. (See Connecting Capella to the PC and probe ► 10.)

2.1

Unpacking 1. Unpack the device carefully. When you unpack the device and accessories, it is a good idea to keep the packing material in which they were delivered. If you need to send the device in for service, the original packing material will protect against damage during transport, etc. 2. Visually inspect the equipment for possible damage. If damage has occurred, do not put the device into operation. Contact your local distributor for assistance. 3. Check with the packing list to make sure that you have received all necessary parts and accessories. If your package is incomplete, contact your local distributor.

2.1.1

Storage, Handling and Transportation MADSEN Capella must be stored in a secure place when not in use and certain precautions must be followed to ensure a longer lifespan and prevent damage. Store according to the technical specifications in Storage environment ► 49, and according to the following instructions:

2.2

•

Store in a secure place; this is sensitive medical equipment and a high force impact may alter calibration and/or damage the equipment.

•

Store all cables in a loose circular manner; kinking and bending the cable may cause loss of power and/or incorrect recordings.

•

Do not store equipment belonging to more than one system in the same space. The hardware was specifically calibrated for the combination of parts; accidentally swapping parts may result in misdiagnosis.

Assembling Capella Caution • Install OTOsuite on the PC before you connect to MADSEN Capella from the PC.

Capella is fully assembled on delivery. Once OTOsuite has been installed, you simply have to connect cables.

2.2.1

Front and top views of Capella This section outlines the available connections of the Capella device. Use these diagrams as a reference when connecting a computer or the ER-10D OAE probe to Capella. Actual connectors on your system may differ slightly from the pictures

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2 Unpacking and Installing Capella and the Otoacoustic Emissions Module

shown; however, they will have the same labels.

Warning • The Capella unit obtains power from the USB port. Make sure to connect the device while the computer is OFF, and then turn on the computer to install the hardware drivers.

A. USB Cable: Connection to computer B. OAE Probe: 8-Pin mini DIN connector

2.2.2

C. Power indicator D. Probe test cavity

Connecting Capella to the PC and probe Follow this procedure to connect Capella to your PC and start the driver installation: 1. Ensure that OTOsuite has been installed on the PC. For instructions on installing OTOsuite, see the OTOsuite Installation Guide, which you can find on the OTOsuite installation medium (disk or memory stick). 2. Shut down the PC. 3. Connect the ER-10D OAE probe to Capella. Make sure that you only use probes provided with your system, the system is calibrated for exclusive use with the provided probe. 4. Insert one end of the USB cable in the USB port on Capella and the other end in a USB port on the computer. 5. Power on the PC. The computer will detect the Capella device automatically and install the driver.

Note • If you do not have an open USB port on your computer, you can use a powered USB hub. The hub must be powered because the MADSEN Capella draws the full 500 mA supply current from the USB. A non-powered hub is only guaranteed to be able to deliver 100 mA.

2.2.3

Switching off Capella To switch off Capella, disconnect the USB cable from the computer or switch off the computer.

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2 Unpacking and Installing Capella and the Otoacoustic Emissions Module

2.3

ER-10D OAE Probe The ER-10D Probe consists of the probe head with removable tip, 12 inches (30.5 cm) of flexible silicon tubing that connects the replaceable probe tip to the preamp enclosure, and 5 feet (1.52 meters) of flexible cable that extends from the preamp enclosure to the mini DIN connector.

A. Preamp box

B. C.

Probe cable connector Probe tip

Connect Only To: •

Capella 10D OAE connector.

•

Ear of patient on Insertion side (appropriate eartip must be connected to probe).

Warning • Do not connect this component to any other device.

Warning • Never connect the probe to a patient without an eartip.

2.3.1

Probe tip replacement If the probe tip is plugged or not functioning, you can change it.

To remove the probe tip: •

Using a small pointed object, such as a pen or small screwdriver, push in the notches on the left and right sides of the rear of the probe microphone casing until each tab is released.

•

Slide the probe tip off the front of the probe and discard.

To replace the probe tip:

Caution • If the probe tip is not inserted completely and properly, the ER-10D probe will not function correctly.

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2 Unpacking and Installing Capella and the Otoacoustic Emissions Module

1. Align a replacement tip with the front of the probe. The tip will only fit in one direction. 2. If the probe tip does not fit securely on the probe, remove the probe tip and reorient it. 3. Press lightly on the tabs to snap them into place. The tabs should be flush with the probe body. The probe is used, with a disposable foam eartip or with a disposable plastic eartip specially designed for the probe, to deliver the stimulus signals and to allow for proper recording of the OAEs produced by the ear. The disposable eartips help the probe fit the ear canal to provide isolation from outside noise sources in order to obtain clear OAEs. The probe should not be used without an eartip. The size of the eartip used will vary depending on the size of the patient’s ear canal.

2.4

Foam Eartips Eartips are used to provide a seal on the ear canal, preventing noise from affecting the stimulus, and creating a chamber for the stimulus to maintain a proper level.

Foam Eartips: OAE 14 mm

Caution • Do not reuse.

Intact Skin Only Eartips are to be used topically over intact skin only. Do not apply over infected skin.

Risk of Sensitivity All Foam Eartips sold by Otometrics are made of hypo-allergenic foam. These products do not contain latex.

Directions 1. Attach the foam eartip to the OAE probe prior to placing it on the patient. 2. Roll the foam tip between your fingers to decrease its volume. 3. Insert into ear canal and hold in place to let the foam expand. Pulling slightly down and back on the ear lobe can sometimes help align the ear canal for easier insertion. 4. Discard after use.

2.5

Plastic Eartips Eartips are used to provide a seal in the ear canal, preventing noise from affecting the stimulus, and creating a chamber for the stimulus to maintain a proper level.

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2 Unpacking and Installing Capella and the Otoacoustic Emissions Module

Various Eartips: 04 mm, 07 mm and 09 mm shown; for use with OAE Probe.

Pediatric Treetips (yellow) ; for use with OAE Probe

Caution • Do not reuse.

Intact Skin Only Eartips are to be used topically over intact skin only. Do not apply over infected skin.

Risk of Sensitivity All Plastic Eartips sold by Otometrics are made of hypo-allergenic silicon or similar polymers. These products do not contain latex.

Directions 1. Attach the plastic eartip to the OAE probe prior to placing it on the patient. 2. Insert into ear canal. Pulling slightly down and back on the ear lobe can sometimes help align the ear canal for easier insertion. 3. Discard after use.

Caution • Using the wrong size tip can lead to improper seal, resulting in noise issues or decreased stimulus sound levels while testing.

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3

Preparing for testing The quality of any OAE test depends on many factors. Specifically, patient state, probe placement, and ambient noise have a strong influence on test results.

Ambient and Patient Noise For best results, ambient noise should be minimized. In noisy environments, estimates of response amplitudes may be lower. A sound booth is optimal for testing but a quiet room (background noise level below 40 dB SPL) is usually suitable. To further minimize noise interference, cooperative patients should be instructed not to move and try not to swallow during testing. The patient should be placed in positions that minimize breathing noises.

Client State In general, it is best to test clients when they are sitting or lying down quietly. It is recommended that infants be tested midway between feedings when they are least likely to be sucking or engaging in other artifact-producing activity.

Equipment Preparation It is important that hygienic precautions are taken to protect the client from cross-infection. Be sure to follow any established infection control procedures for the setting in which you are working. Always use a new and clean eartip. Check for any damage that may have occurred to the equipment since its last use. Turn on the equipment and run the OTOsuite software.

Warning • Turn on the equipment before inserting the probe in the patient’s ear canal.

Warning • If any cables appear torn or the probe is damaged, do not test any patients. Have the equipment checked by the equipment manufacturer or by service personnel at an authorized workshop.

Ear Inspection An otoscopic inspection of the external ear canal and tympanic membrane before probe fitting is recommended to determine whether a proper probe seal is possible. Debris and fluid inside the ear canal may prevent OAEs from being detected. Cleaning the ear canal should ONLY be conducted by a certified audiologist or physician trained in this procedure. NEVER insert anything inside the ear canal in an effort to clean the ear canal. Severe injury may result to the patient if someone who has not been trained in this procedure attempts to clean the ear canal.

Warning • Do not clean the ear canal unless you are a certified audiologist or physician trained in this procedure. Severe injury and hearing loss may result to the client if the procedure is not done properly.

3.1

Using an ER-10D probe A quality probe fit will optimize stimulus presentation and reduce ambient noise in the ear canal. 1. Place the eartip fully on the probe tip. Never connect the probe to a patient without an eartip.

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3 Preparing for testing

2. Use the clip on the preamp box to attach the preamp box to clothing or bedding. The position of the probe must remain stable throughout the recording to ensure proper testing. If the probe moves, the movement will generate noise and may cause the ear canal seal to open. Make sure the cable is not pulling or pushing on the probe when securing it. 3. Insert the probe firmly but gently into the ear canal. Lift gently the outer ear during insertion to straighten the ear canal to ensure proper placement.

Notes: •

Only individuals trained in these procedures should conduct the insertion of the eartip.

•

It is important that hygienic precautions are taken to protect the client from cross-infection. Be sure to follow any established infection control procedures for the setting in which you are working.

•

Do not clean the ear canal unless you are a certified audiologist or physician trained in this procedure. Severe injury and hearing loss may result to the client if the procedure is not done properly.

•

Only appropriate eartips manufactured for the ER-10D probe should be used.

•

The tip should fit snugly in the ear canal to form a seal.

•

The tip should not be loose or penetrate too deeply into the ear canal.

Fig. 1

ER-10D OAE Probe with foam ear tip

Warning • Eartips are not reusable.

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4

Measuring Otoacoustic Emissions with Capella Otoacoustic emissions are small in amplitude; to record them, Capella uses a very sensitive microphone inside the probe. Due to the sensitivity of the recording microphone, ambient noise and noise generated by the patient such as talking, coughing and crying can hamper the detection of OAEs. A suitable testing environment and a proper probe fit are necessary for successful OAE measurements. Debris inside the ear canal may also hamper the recording of OAEs. Recording of OAEs are also affected by the physical state of the tympanic membrane and middle ear. An abnormal state of either of these elements (e.g., infection of the middle ear) can adversely affect the recording of OAEs.

4.1

Measuring Distortion Product OAEs DPOAEs are responses generated by the cochlea to a two-tone stimulation presented to the ear. DPOAEs are generated by most normal healthy ears, and can be used to evaluate cochlear function. Each of the two applied stimulus pure tones is characterized by its frequency and sound intensity or level. The distortion products produced by the cochlea are a biproduct of the two stimulation frequencies, denoted F1 and F2 and their two corresponding intensities or sound levels (L1 and L2). The largest distortion product occurs at a frequency that is two times F1 minus F2; ((2*F1) - F2). During acquisition, Capella can test single or multiple DPOAE frequency pairs according to user specifications. The relationship between the two stimulation frequencies, the F2/F1 ratio, can be specified by selecting one frequency and the ratio and then allowing the system to calculate the second frequency value or by entering values for both F1 and F2 directly. The sound level of stimulation signals, L1 and L2, are also user selectable for each test conducted. After testing, the user can review and print out results of the recorded DPOAEs. The DP I/O screen is used to record a patient’s response to a specific frequency pair at different intensity levels.

4.1.1

The DP Otoacoustic Emissions Screens Both the DP-gram screen and the DP I/O screen contain the same basic elements:

DP-gram

A. Control panel B. Result graph: DP-gram or DP I/O graph C. Spectrum graph

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D. Probe Fit - Time graph E. Probe Fit - Frequency graph F. Legend box/Overlays box/Data table

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DP I/O

A. Control panel B. Result graph: DP-gram or DP I/O graph C. Spectrum graph

4.1.1.1

D. Probe Fit - Time graph E. Probe Fit - Frequency graph F. Legend box/Overlays box/Data table

The Otoacoustic Emissions Control Panel A. B. C. D. E. F. G.

Ear Selection button Sequence button Measurement buttons Pause/Continue button Information panel Artifact Reject Level slider (TEOAE/SOAE only) Probe Fit button

Ear Selection button Use the Ear Selection button to indicate which ear you are going to test.

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Sequence button If you want to make two or more measurements immediately after each other, you can select the check boxes next to the relevant measurement buttons. Then, when you click the Sequence button, the selected tests will be performed sequentially.

Measurement button You can specify different measurement parameters and acceptance criteria for each measurement button. For information about configuring the measurement buttons, see Configuring measurement buttons in DP-gram ► 23 or Configuring measurement buttons in DP I/O ► 24. To start a measurement, click the measurement button. After you click a measurement button, it changes to a Stop button and can be used to abort the measurement. During the measurement, the button acts as a progress bar, filling with green as the test progresses.

Pause/Continue button When a measurement is in progress, the Pause button is active, and you can click the button to pause the test. After you click the Pause button, it becomes a Play button, and you can click it again to continue the test.

Information panel If you hover the mouse over a measurement button in the control panel, information about the test configuration settings for the button are displayed in the information panel. The information is also displayed while a measurement is in progress.

Artifact Reject Level (TEOAE and SOAE only) During acquisition, unwanted spikes or artifacts caused by various sources of sound can be eliminated or severely reduced by proper adjustment of the artifact rejection level.

Probe Fit button The probe fit test is always performed immediately before and after a test. You can also manually start a probe test by clicking the Probe Fit button. (For more information, see Probe Fit ► 35.)

4.1.1.2

The results graph in DP-gram and DP I/O The DP-gram test records the distortion products for fixed levels at different frequencies. The DP I/O test records the distortion products for fixed frequencies at different levels. The results graph (DP-gram or DP I/O graph) displays the measured distortion product for each of the tested points. More than one measurement may be displayed in the results graph, depending on your selection in the Legend box. Other information such as the noise floor and standard deviation may be displayed, depending on the overlays that you select. During a measurement, the progress of the test can be seen in the results graph. The graph is generated as it is acquired, showing the current DP level for the tested intensities. The program cycles through all the test points until the selected total number of sweeps has been completed. As each block is acquired, the results are refined. Each point in the graph displays the average of the sweeps completed so far. The distortion product response that is displayed in the results graph depends on the option that has been selected in the Displayed DP field (Options > Otoacoustic Emissions, View, Misc). The default is to display DP1 ((2*F1) - F2) for each frequency measurement, but it is also possible to select DP2 ((2*F2) - F1).

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4 Measuring Otoacoustic Emissions with Capella

As a default, the noise floor is displayed, and for a DP-gram measurement, L1 and L2 are also displayed by default, but you can select whether they are shown or hidden in the Overlays box (See Overlays - DP-gram and DP I/O ► 21) .

Remeasuring a point After a DP-gram or DP I/O test has been completed, you can remeasure a point in the curve. Right-click on the point you want to remeasure and then click Remeasure point.

4.1.1.3

The Spectrum graph The Spectrum graph displays the results for the currently selected point on the DP-gram. A. Signal-to-Noise

ratio of the selected DP

L1 and L2 are the measured levels of the pure tone primaries that were presented. The measured level may differ from the selected level if the probe was occluded or if the system was not properly calibrated or due to standing waves. DP1 ((2*F1) - F2) and DP2 ((2*F2) - F1) are the resulting distortion products.

4.1.1.4

The Legend box You use the Legend box to select which measurements are displayed in the DP-gram. Each line in the Legend represents a measurement button and the corresponding curve that has been recorded.

20

A. Curve displayed in graph

D. DP-gram Measurement Details button

B. Curve not displayed in graph

E. Overall result

C. No measurement recorded for the button

F.

Comment button

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