ERO.SCAN Operating Instructions April 2001

M A I CO

Operating Instructions ERO•SCAN™

Table of Contents

Page

1. Introduction 2. Important safety instructions 3. Descri ption 3.1 Descri ption of Otoacoustic Emissions 3.2 How does the MAICO ERO•SCAN™ work 4. Getting started 4.1 Unpacking your instrument 4.2 Connecting the printer 4.3 Environmental conditions 4.4 Quick start 4.5 Installing the optional external probe 4.6 Testing with the external probe 5. Performing the DPOAE or the TEAOE test 5.1 Preparing the patient for testing 5.2 The control buttons 5.3 Turning on the instrument 5.4 Testing in the „Default“ mode 5.5 To begin testing 5.6 Auto calibration and test 5.7 Reviewing the test result 5.8 Printing the test result 5.9 Test technique 5.10 Noise sources 6. Interpreting test results 6.1 Understanding the display 6.2 Understanding the DPOAE printed results 6.3 Understanding the TEOAE printed results 6.4 A note about rounding 7. Quick reference guide 7.1 Battery installation 7.2 Changing printer paper 7.3 Attaching the earti ps 7.4 Probe ti p replacement 7.5 Probe ti p replacement of the external probe 7.6 Setting the built-in clock 7.7 Changing instrument settings 7.8 Advanced options for DPOAE-testing 7.9 Advanced options for TEOAE-testing 8. Recommended literature 9. Care and maintenance of the instrument 10. Trouble shooting 11. Technical data 12. Warranty, maintenance and after-sales service 13. Safety regulations 14. Certificate of conformity 15. Front panel layout and rear panel connections

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1 Introduction Thank you very much for purchasing a quality product from the MAICO family. This automatic OAE-test system MAICO ERO•SCAN™ is manufactured to meet all quality and safety requirements, and has been certified with the CEsymbol according to Medical Directive 93/42/EEC. In designing the MAICO ERO•SCAN™ we placed particular importance in making it a user-friendly device, meaning its operation is simple and easy to understand. And because all functions are software controlled, upgrading later to new, extended measurement functions will be simple and inexpensive. That means that you have invested in a device that will adjust to your future needs. This user manual should make it as easy as possible for you to become familiar with the functions of the MAICO ERO•SCAN™. Please open out the flap of illustrations on the last page. The descri ption of the position (e.g. æ ) of controls, displays and connections, found again in the text, will make it easier for you to learn how to operate the MAICO ERO•SCAN™. If you have problems or have ideas for further improvements, please get in touch with us. Simply call. Your MAICO-team

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2 Important safety instructions The MAICO ERO•SCAN™ Otoacoustic Emission (DPOAE and TEOAE) Test Instrument is designed to be used only by those individuals trained to perform the testing for which it has been designed. No person should attempt to use this instrument without the necessary knowledge and training to understand how this equi pment is to be properly utilized and interpreted. The MAICO ERO•SCAN™ instrument probe ti p must not be inserted into any ear at any time without a disposible earti p properly affixed. Precautions •

READ THIS ENTIRE MANUAL BEFORE ATTEMPTING TO USE THIS UNIT.

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Use this device only as described in this manual.

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Use only the disposable earti ps designed for use with this instrument.

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Never insert the probe ti p into the ear canal without affixing an earti p.

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The earti ps are disposable and for single patient use only. Do not clean or reuse earti ps.

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Use disposable alkaline 1.5V AA batteries only. Do not use rechargeable cells in this device; do not mix battery types; and do not mix old and new batteries.

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Remove the batteries from the instrument if it will not be used for 4 weeks or more.

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Do not immerse the unit in any fluids. See the Cleaning section of this manual for proper cleaning procedures.

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Do not drop or otherwise cause undue impact to this device. If the instrument is dropped or otherwise damaged, return it to the manufacturer for repair and/or calibration. Do not use the instrument if any damage is suspected.

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Use and store the instrument indoors only. Do not expose this instrument or its accessories to temperatures below 40ºF (4ºC) or above 100ºF (38ºC), or to relative humidity of more than 75%.

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Do not attempt to open or service the instrument. Return the instrument to the manufacturer for all service. Opening the instrument

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Operating Instructions ERO•SCAN™ case will void the warranty.

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Do not operate the printer if the power supply has a damaged cord or plug. See the instructions on the following page.

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Do not expose the printed results to sunlight or heat. Printing on thermal paper fades with exposure to light or heat.

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Photocopies of test results should be made if the records are to be kept indefinitely.

Disclaimer The MAICO ERO•SCAN™ Test Instrument is designed to be a screening device for hearing loss. Sensitivity and specificity of this type of device are based on the test parameters defined by the user, and may vary depending on environmental and operating conditions. The presence of otoacoustic emissions suggests normal outer hair cell function, which in turn correlates to normal hearing. However, a passing result using this instrument is not an indication that the full auditory system is normal. Thus, a passing result should not be allowed to override other indications that hearing is not normal. A full audiologic evaluation should be administered if concerns about hearing sensitivity persist. A REFER test result should not be assumed to be an indicator of a lack of auditory function, however it should be followed with full audiologic diagnostic testing. NOTICE: Under certain circumstances, especially in low-humidity environments, common electrostatic discharge may cause this instrument to turn itself off. This effect causes no permanent damage, and the instrument may be turned on again by the normal procedure of holding the down button. Printer Rechargeable Battery Precautions • Do Not Attempt to Open the Battery Pack! The printer battery pack contains Nickel-Cadmium cells. Cadmium is a potentially toxic heavy metal, and exposing the cells increases the risk of leakage or short-circuiting. • Do not short-circuit the battery contacts. This could cause burns or a fire. GEBA_ero_FOTO_e.01a.wpd

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Operating Instructions ERO•SCAN™ • Disconnect the printer power supply before removing or replacing the battery pack. • Observe local regulations for handling, transport, and disposal of Nickel-Cadmium cells. Regulations in many areas prohibit the disposal of Nickel-Cadmium cells. Complete battery packs may be returned at the user’s risk and expense to the manufacturer for ecological recycling. • The battery pack must be charged for a minimum of five hours before using the printer for the first time. Failure to fully charge the battery pack before use may reduce the lifetime of the battery pack.

Printer Power Supply Precautions READ THIS SECTION CAREFULLY BEFORE USE! • The printer power supply converts main voltage (230V~) to a safe low voltage (12V DC) for charging the printer battery pack. Use only the power supply supplied for this purpose. • This product is for indoor use only. Do not expose to water or excessive dust. • Do not cover the power supply body as it may result in excessive heating. The power supply operates when the plug is inserted into an outlet. To turn it off, remove the plug from the outlet. The outlet must be easily accessible and located near the printer. Should a faulty condition occur, remove the plug from the outlet immediately. • High Voltage Inside! Do not remove the power supply cover! All service or maintenance must be done by trained personnel. Return the power supply to the manufacturer for service.

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Operating Instructions ERO•SCAN™

3 Descri ption The MAICO ERO•SCAN™ Otoacoustic Emission test instrument is a handheld device designed to provide an objective test of outer hair cell function through the measurement of Distortion Product Otoacoustic Emissions (DPOAEs) or Transient Evoked Otoacoustic Emissions (TEOAEs). Versions with either DPOAEs or TEOAEs or a combined instrument with both methodes are available. The MAICO ERO•SCAN™ consists of the hand-held unit, printer, single-use earti ps and other accessories. The MAICO ERO•SCAN™ instrument may be used as a screening tool, or in conjunction with conventional tests as part of a full audiological evaluation. The MAICO ERO•SCAN ERO•SCAN™ instrument contains the hardware and software for generating the test tones, measuring and displaying the DPOAEs or TEOAEs, and storing the results until they are printed. The plastic housing contains circuit boards that provide the signal processing and display the test results. The instrument also contains four A/UM-3/R6 alkaline batteries to power the device. The instrument uses a liquid-crystal display (LCD) and three light-emitting diodes (LEDs) to provide a visual display of test data and test conditions to the operator. The probe section of the instrument houses a microphone and two speaker tubes which produce test stimuli and measure the sound pressure level (SPL) present in the sealed ear canal. Interface of the instrument to the ear canal is accomplished through disposable earti ps made of industrial elastomer, which fit onto the probe ti p. The disposable earti ps are colour coded to facilitate easy selection by size. Four membrane-type push buttons located on the keypad of the device allow the user to control testing and printing, and to reset test protocols. Printing will commence upon placement of the instrument into the cradle. In the default test mode, the MAICO ERO•SCAN™ instrument will store the results from one patient (left and right ear) in its non-volatile memory for subsequent printing. However, the MAICO ERO•SCAN™ instrument can store up to 50 test results. The results are displayed via the LCD on the front of the device and are stored in the device’s internal memory. After testing is completed, results can be printed using the printer and/or exported to a computer. Test results are stored in the non-volatile memory so the operator can delay printing until a later time if desired. GEBA_ero_FOTO_e.01a.wpd

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PC-Interface: A serial RS 232C interface for data transfer to a connected computer is built in. A program for Windows is available as accessory.

3.1 Descri ption of Otoacoustic Emissions 3.1.1 What Are DPOAEs? Distortion product otoacoustic emissions are acoustic signals that can be detected in the ear canal of a person with normal outer hair cell function, subsequent to stimulation of the auditory system with a pair of pure tones at frequencies f1 and f2. The resulting emission of interest is the distortion product tone at the frequency 2 f1-f2. 3.1.2 What Are TEOAEs? Transient Evoked Otoacoustic Emissions (TEOAEs) are acoustic signals that can be detected in the ear canal of a person with normal outer hair cell function, subsequent to stimulation of the auditory system with a series of wideband clicks. 3.1.3 What Do Otoacoustic Emissions Results Tell Us? Available evidence suggests that otoacoustic emissions (OAEs) are generated by the cochlea’s outer hair cells, and that the presence of OAEs is an indication that the outer hair cells are normal. Although OAE test data provide no indication of inner hair cell function, or of hearing ability, current research indicates that the majority of hearing-impaired individuals will be identified by a simple OAE test. Patients who fail to generate OAEs should be re-screened and/or referred for additional audiological testing. 3.1.4 How Does the MAICO ERO•SCAN™ Device Measure DPOAEs? The MAICO ERO•SCAN™ instrument generates a series of test tones, directs them into the ear canal, and then measures the level of the DPOAE tone generated by the cochlea. By using different test frequencies, the MAICO ERO•SCAN™ device provides an estimate of outer hair cell function over a wide range of frequencies. 3.1.5 How Does the MAICO ERO•SCAN™ Device Measure TEOAEs? The MAICO ERO•SCAN™ instrument generates a series of clicks, directs them into the ear canal, and then analyses the spectrum of the returning signal, separating the noise and emission. By using bandpass filters, the MAICO ERO•SCAN™ device provides an estimate of outer hair cell GEBA_ero_FOTO_e.01a.wpd

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Operating Instructions ERO•SCAN™

function over a wide range of frequencies.

3.2 How Does the MAICO ERO•SCAN™ Device Work? The digital signal processor in the instrument generates two pure tones (f1 and f2) or a series of wideband clicks for TEOAEs through a digital-to-analog converter. These tones or clicks are presented to the ear via speaker tubes located in the probe. A microphone in the probe measures the sound in the ear canal and transmits the signal to the analog-to-digital converter. The digital signal processor then uses Fast-Fourier Transforms (FFTs) to filter the signal into narrow frequency bands, and detects any emissions present. The level of these emissions can be compared with the average level of the noise. The SPL and frequencies of the test tones and the averaging time used to process the signals can be determined by the tester through adjustable settings maintained in static memory within the MAICO ERO•SCAN™ instrument. 3.2.1 What Frequency Range of Hearing is Estimated? DPOAEs: Roughly 1 kHz to 6 kHz. Since the health of the hair cells in the region of the f2 test frequency are estimated, and a) the 2f1-f2 emission frequency is at about six-tenths of the f2 frequency, b) emissions tend to be weak below 600 Hz or so, and c) the ambient noise tends to be highest at low frequencies, the lowest f2 test frequency that can be routinely measured is about 1 kHz. TEOAEs: Roughly 500 Hz to 4 kHz. TEOAEs can be reliably recorded at lower frequencies than DPOAEs, but cannot be measured reliably above 4 kHz.

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4 Getting started 4.1 Unpacking your instrument Your MAICO ERO•SCAN™ is carefully inspected and packed for shi pping. However, it is a good practice to thoroughly inspect the outside of the shi pping box for signs of damage. If any damage is noted, please notify the carrier immediately. Carefully remove the instrument from the shi pping box. Remove the plastic bags and inspect the parts for any damage. Notify the carrier immediately if any mechanical damage is noted. This will assure that a proper claim is made. Save all packing material so the claim adjuster can inspect it as well. Notify your dealer or MAICO when the adjuster has completed the inspection. SAVE ALL THE ORIGINAL PACKING MATERIAL AND THE SHIPPING CONTAINER SO THE INSTRUMENT CAN BE PROPERLY PACKED IF IT NEEDS TO BE RETURNED FOR SERVICE OR CALIBRATION. Please check that all accessories listed below are received in good condition. If any accessories are missing or damaged, immediately notify your dealer or MAICO. Standard accessories: -

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MAICO ERO·SCAN™ Hand-held Unit...

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Cradle...

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Printer...

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Printer Power Supply...

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Printer Cable...

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Headphones...

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Kit with 156 Earti ps (12 sizes)...

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Probe Ti ps...

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AA/UM-3/R6 Alkaline batteries (already installed in instrument)

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Thermal printer paper roll (already installed in printer)

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Operating instruction manual

4.2 Connecting the printer -

Connect one end of the printer cable Ó into the port Ë located on the underside of the cradle as shown in Figure 1 to the right.

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After firmly pushing the broad connector end into place, turn the screws on either side to tighten it.

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Insert the two cables into the slots Ì provided on the bottom of the cradle.

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Return the cradle to right side up (Figure 2).

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The long end of the cable Ó should be plugged firmly into the inlet at the rear of the printer Ò. The flat side on the small connector (look for the arrow) goes to the bottom of the printer. The cover of the connector will slide back to ease installation of the connector. Plug the short end Ô of the cable Ó into the printer power supply. Plug the power supply cord into an electrical outlet. The printer indicator light Î (located on the front of the printer) will shine a steady orange. This indicator will turn to green once the battery pack is sufficiently charged and if paper is installed. The printer must be

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I

J

K

B

C

Figure 1 Installation printer cable

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Figure 2 Connector power supply 851946/4

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Operating Instructions ERO•SCAN™

charged for 5 hours prior to use. See the precautions for the printer power supply at chapter 2. NOTE: The printer runs on a Ni-Cad rechargeable battery pack. The printer will not run from the power supply, the power supply only charges the battery pack. The battery pack must be charged for a minimum of five hours before using the printer for the first time. The printer will not function without a charged battery pack attached. Failure to fully charge the battery pack before use may reduce the life of the battery pack. 4.3 Environmental conditions The MAICO ERO•SCAN™ should be operated in a quiet room, so that the examinations are not influenced by outside noises. Electro-medical instruments, which emit strong electromagnetic fields (e.g. microwaves - radiotherapy devices), can influence the function of the MAICO ERO•SCAN™. Therefore the use of these instruments is not allowed in close proximity to the MAICO ERO•SCAN™. The test room must be at normal temperature, usually 15/C / 59/F to 35/C / 95/F, to guarantee precise measuring results. If the device has been cooled down (e.g. during transport), please wait until it has warmed up. 4.4 Quick start These steps will allow you to quickly start using the MAICO ERO•SCAN™ Test System. If you have a DPOAE or combined instrument it will be in the DPOAE test mode. If you have a TEOAE instrument it will be in the TEOAE test mode. Be sure to perform the necessary otoscopic examination prior to testing. Read the entire manual before testing patients. -

Place an earti p as far down as possible on the probe ti p.

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Turn on the MAICO ERO•SCAN™ instrument by pressing the large ? down arrow button ë.

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Select the test ear by pressing the = left ê or < right í arrow key. Insert the earti p deeply into the patient’s ear canal to obtain a seal. When a seal is obtained, the MAICO ERO•SCAN™ instrument will automatically begin

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Figure 3 Eartips

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the test by first calibrating and then testing emissions. -

The red ERROR LED æ will illuminate if there is noise in the environment. This flashing is normal and will often occur. Once the testing is finished, the unit will display “PASS” or “REFER” on the LCD display.

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When testing is completed on both ears, turn the printer on by pressing the green button on top and place the hand-held unit on the cradle. The most recent test results for both ears will automatically print out.

Figure 5 Testing

Figure 6 Printout of test result

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4.5 Installing the optional external probe -

Remove the protective cover of the external probe plug ñ at the top of the MAICO ERO•SCAN™ using a tool or the fingernail (see figure 7).

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Turn off the MAICO ERO•SCAN™ and put the external probe connector ò into the plug ñ on the top of the MAICO ERO•SCAN™ (figure 8). The connector ò will fit only in one direction. The arrows on the connector ò should face the display é on the MAICO ERO•SCAN™.

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Turn on the MAICO ERO•SCAN™. The yellow TEST light ç on the display will light shortly, indicating the MAICO ERO•SCAN™ has detected the presence of the external probe. Disconnect and reinsert the connector ò if the yellow light ç is not seen.

Figure 7 Removal of Cover

Figure 8 Connection of External Probe

Note: All testing is done through this probe until it is unplugged. MAICO ERO•SCAN™ settings do not need to be changed in order to use this probe. 4.6 Testing with the optional external probe -

The external probe uses the same disposable eartips as the MAICO ERO•SCAN™ probe. Place the eartip ö fully onto the probe tip õ (see Figure 9). -

Never use the probe without an eartip installed. Use the shirt clip on the external probe housing ó to secure the probe to clothing or bedding.

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Check the ear canal for cerumen or vernix before inserting the probe.

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Turn on the MAICO ERO•SCAN RO•SCAN™ and select the ear to be tested.*

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Insert the probe into the ear canal (Figure 10). Lift gently on the outer ear during insertion to straighten the ear canal and ensure proper placement.

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Figure 9 Correct Placement of the Eartip

Figure 10 Correct inserted External Probe 851946/4

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The AUTO-START function automatically begins the test when the probe is inserted correctly. If the MAICO ERO•SCAN™ does not start the test, reposition the probe.

*NOTE: When testing infants or young children it is recommended that the probe is placed in the ear before selecting the test ear on the MAICO ERO•SCAN™. When the child is quiet, select the ear to be tested. 17 18 19 20 21

Figure 11 The External Probe

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5 Performing the DPOAE or the TEOAE test 5.1 Preparing the patient for testing - Otoscopic examination of the patient’s ear canals should be performed prior to testing. Excessive cerumen or vernix in the ear canals may interfere with the test and give invalid or incomplete results. Patients with excessive cerumen, debris, or foreign bodies in the ear canals should be referred to an audiologist or physician for removal of the blockage prior to testing. -

Place the patient in a position that will allow the MAICO ERO•SCAN™ instrument to be held steady while testing is in progress. The patient should remain still and quiet while the test is being performed.

5.2 The control buttons -

™

The MAICO ERO•SCAN

5

6

7

8

instrument uses four

buttons to control all functions of the instrument. These buttons are arranged in a directional cursor format. The arrows on the keys (= left ê, < right í, > up ì, ? down ë) correspond to the arrows that are used on the screen é. The screen é will indicate which button to push by showing the appropriate arrow. -

NOTE: The > up key ì will always bring the instrument back to either the previous menu or the Main Menu. The > up key ì will also turn the unit off when the 9 10 11 12 Figure 12 Control instrument is at the Main Menu. buttons and displays

5.3 Turning On the Instrument -

To turn on the MAICO ERO•SCAN™ instrument, press the large ? down key ë located below the instrument’s display screen é. Three small lights (red æ, yellow ç and green è) will appear for a Figure 13 Figure 14 Turn on Start display short moment just above the display screen. The green ready light æ will remain on. On the display é the text shown in figure 14 will appear shortly when DPOAE is set or selected. If

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TEOAE is set or selected the text at the bottom will be TE instead of DP. -

If the batteries have sufficient power, the MAICO ERO•SCAN™ instrument will automatically check the date and time settings. If there are no date/time errors detected, the Main Menu (Figure 15) will appear on the display.

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NOTE:

If

this

is

the

first

time

the

MAICO

Figure 15 Main menu

ERO•SCAN™ instrument is being used, or if you wish to change the date or time, see Setting the Clock in chapter 7.3 for instructions on setting the correct date and time. -

The MAICO ERO•SCAN™ instrument has an automatic shutdown feature, designed to prolong battery life. The unit will automatically shut down after 2 minutes (default) of inactivity. To turn it again on, simply press the large ? down key ë. This feature can be re-programmed to various periods of inactivity before shut-down. (See chapter 7.6 for further information on this feature.)

5.4 Testing in the “Default” Mode -

The MAICO ERO•SCAN™ instrument can use a default protocol or a custom test protocol for DPOAE and/or TEOAE. The default protocol will be used unless a custom protocol is selected. See Changing Instrument Settings in chapter 7.6. Chapter 7.7 contains information on custom protocols, and the Advanced Options menu allows the user to change test protocols.

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The settings for DPOAE testing in the default mode are as follows: Number of Frequencies Tested = 3

Averaging Time = 2 Seconds

Frequency Range = 2 kHz to 4 kHz

“PASS” SNR (Signal-to-Noise Ratio) = 5 dB

P1 (Intensity of f1) = 65 dBSPL

Number of PASSing Frequencies for Test “PASS” = 3

P2 (Intensity of f2) = 55 dBSPL

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The settings for TEOAE testing in the default mode are as follows: Number of Frequencies Tested = 6 Frequency Range = 1 kHz to 4 kHz Click Presentation Level = 65 dBSPL

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Averaging Time = 16 Seconds “PASS” SNR (Signal-to-Noise Ratio) = 4 dB Number of PASSing Frequencies for Test “PASS” = 3

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5.5 To Begin Testing To begin testing in the default mode, place an eartip â as far down as possible on the probe tip ã (see figure 17). For proper eartip Figure 17 Figure 16 Proper sitting eartip Place eartip attachment refer to chapter 7.3. Turn on the instrument by pressing the ? down button ë and select either the = left ê or < right í arrow key to indicate which ear will be tested. After the test ear is selected, the text shown on the display é in figure 20 will appear. This display will verify the test ear and indicates that the unit is in Figure 19 Figure 18 auto-start mode. To obtain a seal and to Turn on Select ear measure OAEs, gently insert the eartip into the patient’s ear canal. It should fit snugly and comfortably. The best test results are obtained when an eartip is inserted deeply into the ear canal instead of flush with the ear canal opening. Figure 20 Start screen

The NOISE and VOLUME bar readings (see figure 20) should be used as an indication how the unit seals the ear canal. If the NOISE and VOLUME bars continue to fill the screen, the unit is not sealing the ear canal and the environmental noise is too high. Make appropriate adjustments until a decrease of these bars is seen. Note that for an adult, the VOLUME bar will decrease to about half, while for a newborn or child, the VOLUME bar will decrease further to the left. The NOISE bar will show a decrease from the original reading. When a seal is obtained, the unit will automatically begin testing and the yellow TEST LED ç will illuminate throughout the test. 5.5.1 Testing children with PE Tubes To test children with PE tubes, the auto-start needs to be disabled. This is accomplished by first inserting the MAICO ERO•SCAN™ with the GEBA_ero_FOTO_e.01a.wpd

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appropriate ear tip into the ear canal and obtaining proper seal. To disable auto-start, at the Main Menu select the ear by HOLDING DOWN the = left ê or < right í arrow key for 3 seconds until the green test light ç turns off. Once the key is released, the MAICO ERO•SCAN™ will calibrate and test as described below. 5.6 Auto Calibration and test -

The

MAICO

ERO•SCAN™

instrument

will

automatically perform a calibration at the start of each test and the text shown in figure 21 will briefly appear on the LCD é. During calibration a series of tones will Figure 21 Calibration be presented to the ear canal to calibrate the levels of the primary tones at the frequencies to be tested. It is very important that the MAICO ERO•SCAN™ unit is held steady in the patient’s ear canal while the yellow TEST LED ç is illuminated. -

Following the automatic calibration of the test tones, a set of bars should appear on the display (figure 22). These are the test results which are displayed as the emissions are measured. Two bars are used to represent each of the test frequencies (DPOAE) or in each of the frequency bands (TEOAE).

Figure 22 Test in progress

Testing is completed when the green “READY” light è is illuminated. Both the tester and patient should remain as still and quiet as possible until the green light è turns on. The graphic display is explained in chapter 6 „Interpreting Test Results“.

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5.7 Reviewing the test results - When testing is completed, a display similar to figure 23 will appear. as soon as the test is complete. The results will be saved even if the unit turns off or the batteries are temporarily removed. -

Figure 23 Test result

This screen again indicates the test ear and further gives the results of the

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test. “PASS” on the screen indicates the patient passed the screening. -

“REFER” indicates that the patient did not pass the screening.

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“NOISY” indicates that excessive noise was present during the test.

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The tester can determine from the display whether the test should be repeated.

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To review the results, push the ? down arrow key to return to the bar graphs.

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After reviewing the results, again push the ? down arrow key ë to return to the Main Menu.

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Once the instrument returns to the Main Menu and a new test for that ear is started, the previous results may not be viewed again unless a printout of the results has been obtained.

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If a patient did not pass, testing can be repeated by selecting the same test ear and starting the procedure again.

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By default, the MAICO ERO•SCAN™ instrument will save only the last test for each ear. When testing is completed, the results should be printed before a new patient is tested.

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Note, however, that the MAICO ERO•SCAN™ instrument can be configured to store up to 50 tests in the unit for printing at a later time. It is important to keep a record of the test number for each patient if this feature is used. See Print Mode/Storing Test Results in chapter 7.6 to set up the device to save 50 tests in memory.

5.8 Printing the test results - It is recommended that the results be printed after each patient. The MAICO ERO•SCAN™ instrument will save the most recent test results for each ear and print only these results in the "Default" mode. This allows the user to retest a patient after a ”REFER” result and to print out only the most recent test result for each ear. If the printer is operating on the battery pack, turn GEBA_ero_FOTO_e.01a.wpd

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Figure 24 Printout of test result 851946/4

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