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Operating Instructions ERO•SCAN™

1. M Operating Instructions ERO SCAN MAICO MAICO Diagnostic GmbH Rohrdamm 7 D 13629 BERLIN Tel 030 38629406 Fax 030 38629499 Table of Contents 1 2 3 10 11 12 Safety regulations 14 15 Introduction Important safety instructions Descri ption 3 1 Descri ption of Otoacoustic Emissions 3 2 How does the MAICO ERO SCAN work 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 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 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 Quick reference guide 7 1 Battery installation 7 2 Changing printer paper 7 3 Attaching the earti ps 7 4 Probe tip replacement 7 5 Probe tip 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 Recommended literature Care and maintenance of the inst
2. The signal to noise ratio TE level minus the noise floor A 114 P indicates that the NX 2 3 X A 1 Feb 26 00 1226 lt p AN TEOAE 2 0 secavg V 7 56 6 4 Hin i 5 NAME CA E P N a 43 Lo ae 3 0 5 T 8 2 0 8 6 14 P 5 A 25 10 84 19 P TT S 3 0 B 6 12P o 3 5 9 40 19 P NOY 40 5 8 13 P F 5niiiiiiiiii Hii be MM ttt 7 d E ILITTITITITITITITIITTII 44 3 0 HERE oaa rara tn CHi IE saanasessesoososases 4 ORMMEHM rennen F 15 10 5 0 5 10 Level dB NF Pass Figure 29 Full result printout signal to noise ratio for the test was equal to or above the SNR criterion The thick bars indicate the noise floor in dB The small bars indicate the emission level in dB GEBA ero FOTO e 01a wpd 25 851946 4 04 01 MD operating Instructions ERO SCAN 6 3 A Note About Rounding of Results The user needs to be aware that the SNR and single PASS criterion are calculated from the full internal precision of the instrument and not from the values shown in the printout for the distortion DP and noise floor NF estimates This approach is used to preserve the full precision of the test results but can result in some apparent errors in the printout due to the effects of rounding n the printout example figure 28 the actual values were assumed at 2 0 kHz for DP 4 5 dB NF 0 4 dB which results in SNR 4 9 dB
3. The Minimum DP amplitude screen as shown in figure 58 is displayed This setting allows the user to set the unit to include minimum amplitude values in the pass refer criterion If the MIN VALUE is set to ON a result is not Figure 58 considered a pass unless the DP amplitude at each Min Amplitude frequency is equal to or higher than the minimum value programmed into the unit in addition to meeting the other pass criteria including the minimum SNR and the number of passing frequencies for Overall Test Pass The minimum DP amplitude value is 5 dB The minimum TE amplitude value is 12 dB 7 7 8 Clock Mode Press the NEXT button to enter the Clock Mode MIN VRLUE CHANGE NEXT CLOCK MODE Figure 59 The menu allows the user to change the clock 24 Hour from 12 hour mode to 24 hour mode To change the clock Ct mode press the CHANGE keys or lt Once you have made your selection press NEXT Figure 59 Clock mode 7 7 9 Language The language setting allows the user to select between LANGUAGE several languages Language options include English ENGLISH French German and Spanish To change the language press the CHANGE keys 9 or 2 until the desired language is shown Once you have made your selection Figure 60 Language Selection press NEXT CHANGE HEST 7 7 10 Reset to Default RESET TO 0 Reset to Defau nu Selecting the left 9 or right
4. The display shows a 6 column graph 2 colums frequency in basic and 3 frequency mode Each frequency DPOAE or frequency range TEOAE is indicated by one or two adjacent columns depending on how many frequencies are tested e g in the default mode where only three frequencies are tested each frequency will be represented by two columns Each row represents 2 dB 2 de Frequency gt 1 colum frequency in of signal to noise ratio SNR For 6 frequency mode example if the column goes to the top of the display then the SNR is 12 dB or higher 6 rows of 2 dB each Signal to noise ratio SNR gt Figure 27 Result display The display is shown while the test is being performed To review the display after the test is finished press the REVIEW key 0 to look at the display For 3 frequency tests two columns for each frequency are used and will be identical For 6 frequency tests each column represents an individual frequency GEBA ero FOTO e 01a wpd 23 851946 4 04 01 ID operating Instructions ERO SCAN 6 2 Understanding the DPOAE Printed Results Each test will generate its own printout Described below is the FULL printout text or graph printouts will be abbreviated 10 11 F The test number wl The ear selected T N SCAN Bi The time and date of the test 1 TV Let Feb 2600 AN DPOAE 20secavg V7 5 based on the setting of the amp Y internal clock 1 NAME s pall 7 Fa
5. 50 66 10 50 67 70 50 68 1050 89 10 50 90 1050 91 70 50 92 70 50 93 70 50 94 70 50 95 15 mm yellow 10 mm green 851946 4 04 01 M Operating Instructions ERO SCAN Internal Probe specifications Equivalent SPL ol Home in Hz Dandwadih Free Field Frequency Response dB SPL Soundfield Tr T T E E a a Sernitivity dBV Pascal 5 dB re MuP 5 amp 40 n te i 10 15k P Frequency Mz T z3 Froqumescy H7 Figure 85 Microphone Fr n gure Pa JA oke acne Figure 86 System Noise Floor nominal Response nominal Zidalochd Goupler Frequansy Respunee a OP Test in Zwisiocsi Coupier P 65 5548 SPL Ret 2 Tad sec 196 30 T E s ia 8 S 70 8 2 3 Jan 1k 5x 108 158 ae D Jk ak 5 5 Frequency Hat P Peequency M2 Figure 87 Sound Source Frequency Figure 88 System Distortion Noise Response nominal nominal GEBA ero FOTO e Ola wpd 5 6 851946 4 04 01 M Operating Instructions ERO SCAN External Probe specifications Pras Field Frequency Resgaran D4 dil SPL Soandfekd Equivatent SPL of Moise in 1 Mz Bandwidth 10 0 9 17 g gt S sm a 3 3 40 bed amp An p m JE 35 300 ik te 10k 15 Frencuescy Ha Frequency Hz Figure 89 Microphone Frequency Figure 90 System Noise Floor nominal Response nominal Zwisiocki Coupler Frequency Response DP Test in ZwisiocHi Coupler P265 55dB SPL 821 2 T 4 see 100 ul ini E v E 3 a x E HE
6. Tips asseeeda a viet a ml beat ST w 4 4 AA UM 3 R6 Alkaline batteries already installed in instrument 1 Thermal printer paper roll already installed in printer 1 Operating instruction manual 4 2 Connecting the printer Connect one end of the printer cable into the port located on the underside of the cradle as shown in Figure 1 to the right After firmly pushing the broad connector end into place turn the screws on either side to tighten it Insert the two cables into the slots provided on the bottom of the cradle Return the cradle to right side up Figure 2 The long end of the cable should be plugged firmly into the inlet at the rear of the printer 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 of the cable into the printer power supply Plug the power supply cord into an electrical outlet The printer indicator light amp 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 GEBA ero FOTO e Ola wpd 1 0 Figure 1 Installation printer cable Figure 2 Connector power supply 851946 4 04 01 MD operating Instructions ERO SCAN charged for 5 hours prior to use See the precau
7. 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 EROeSCAN 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 EROeSCAN device provides an estimate of outer hair cell GEBA ero FOTO e Ola wpd 7 851946 4 04 01 MD operating Instructions ERO SCAN
8. cradle and GEBA ero FOTO e 01a wpd 45 851946 4 04 01 MD operating Instructions ERO SCAN the printer Are there any tests in memory to be printed Printer paper low message appears on LCD Open printer cover and reposition or replace the paper roll If your instrument still does not work properly after this short check please consult your dealer or service centre GEBA ero FOTO e 01a wpd 46 851946 4 04 01 MD operating Instructions ERO SCAN 11 Technical Data C NY The MAICO EROeSCAN is an active diagnostic medical product according to the class lla of the EU medical directive 93 42 EEC Standards IEC 601 1 Approvals U S F D A 510 k 980533 23 03 1998 Environment conditions 15 35 C 4 59 95 F operation 5 50 C 41 122 F storage Maximum humidity 90 storage and operation PROBE SPECIFICATIONS Measurement Type Distortion Product Otoacoustic Emissions DPOAE and or Transient Evoked Otoacoustic Emissions TEOAE Frequency Range DPOAE 1 5 to 6 0 kHz 2 0 to 4 0 kHz default setting TEOAE 0 7 to 4 0 kHz 0 7 to 4 0 kHz default setting Intensity Range 40 to 65 dB sp Maximum Output 90 cB p Microphone Noise 20 dB 2 kHz 1 Hz bandwidth 15 dB 4 1 kHz 1 Hz bandwidth Sampling Rate 31 250 Hz INSTRUMENT SPECIFICATIONS Power Supply 4 AA UM 3 R6 cells Alkaline 6V total Battery Life Approximately 300 tests Instrument Weight 300 g 10 6 oz including ba
9. f a patient did not pass testing can be repeated by selecting the same test ear and starting the procedure again 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 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 el 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 Figure 24 Printout of test result GEBA_ero_FOTO_e 0la wpd 19 851946 4 04 01 MD operating Instructions ERO SCAN it on by pressing the green button before placing the instrument in the cradle The test results that are stored will print out automatically If the printer is plugged into main power it is already on The results of the most recent test from each ear will continue to be stored in memory
10. 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 EROSCAN 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
11. improve the overall accuracy Those samples are included in the final analysis the noisier samples are rejected The improved operation in noise with the new algorithm was so substantial that we conducted a complete replica of our original validation tests in fully impaired ear cavities and were able to verify that no increase in false negatives false passes was introduced The artifact rejection can only reject the noisiest samples in a measurement period If the ambient noise level rises too high and or the eartip seal is poor then all samples will be noisy and accurate measurements will be impossible in this case the test result will indicate noisy GEBA ero FOTO e 01a wpd 60 851946 4 04 01 MD operating Instructions ERO SCAN PROBABILITY OF MISSING MOD SEVERE HL SNR INCIDENCE BY PASS CRITERIA METAL CAVITY 5 0 4 5 4 0 T of 6 FREQ 3 5 u 3 0 4 of 6 FREO Z 2 596 mw o ur 2 096 15 THREE IN 1000 PROBABILITY OF 4 dB OR GREATER SNR IN 3 OF 6 FREQUENCIES 1 096 0 5 15 of 6 FREO 0 096 5 dB SNR Figure 94 Probability of Missing Mod Severe HL GEBA ero FOTO e 01a wpd 61 851946 4 04 01 MD operating Instructions ERO SCAN 12 Warranty Maintenance and After Sales Service The OAE test system MAICO ERO SCAN is guaranteed for 1 year This warranty is extended to the original purchaser of the instrument by MAICO through the Distributor from whom it was purchased and covers d
12. mode place an eartip W as far down as possible on the probe tip see figure 17 For proper eartip Figure 16 Figure 17 attachment refer to chapter 7 3 Place eartip Proper sitting eartip Turn on the instrument by pressing i the down button and select either the left 9 or right arrow key to indicate which ear will be tested After the test ear is selected the text shown on the display in figure 20 will appear This display will verify the test ear and indicates that the unit is in Figure 18 Figure 19 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 ggggg88 flush with the ear canal opening Figure 20 The NOISE and VOLUME bar readings see figure 20 Start screen 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 automatical
13. of Frequencies Tested 6 Frequency Range 1 5 kHz to 6 kHz P1 Intensity of f1 in dB SPL 65 P2 Intensity of f2 in dB SPL 55 Averaging Time 2 seconds Pass SNR Signal to Noise Ratio 7 dB Number of Passing Frequencies for Overall Test Pass 3 TEOAE Number of Frequencies Tested 6 Frequency Range 0 7 kHz to 4 kHz Averaging Time 16 seconds Pass SNR Signal to Noise Ratio 4 dB Number of Passing Frequencies for Overall Test Pass 3 TEOAE CUSTOM Number of Frequencies Tested 6 Frequency Range 1 5 kHz to 4 kHz Averaging Time 16 Seconds Pass SNR Signal to Noise Ratio 4 dB Number of Passing Frequencies for Overall Test Pass 3 GEBA_ero_FOTO_e 0la wpd 49 851946 4 04 01 MD operating Instructions ERO SCAN Test Sequence A complete test sequence consists of an autostart calibration and test phase The autostart phase determines when the calibration phase should proceed while the calibration phase calibrates the level of the tones that will be applied during the actual test phase Artifact rejection is employed during the test phase to reduce the effect of transient noise bursts Immediately after the test button is pressed the autostart phase of the test begins Autostart checks both the quality and stability of the seal by measuring the response obtained from a sequence of test tones The stability of the seal is determined by comparing the responses obtained over time When the level of the response is
14. of clicks applied to the receivers The click sequence is 3 1 1 1 repeated twice Signal and noise floor estimates are obtained by adding subtracting the two response sequences respectively The energy of the signal and noise floor estimates in various frequency bands is obtained in real time and displayed once per second The average peak pressure of the stimulus is calculated after completion of the test Artifact rejection is employed during the test phase to reduce the effect of transient noise bursts by the use of an adaptive rejection threshold The unit attempts to accept the quieter sections of the test while rejecting the noisier portions of the test When the noise level is approximately constant during the test the instrument will tend to accept most of the data in the test However as the level of the noise becomes more variable over time the instrument will attempt to accept the quieter portions of the recording Noise estimates are obtained approximately 32 times per second and a suitable threshold is estimated from the data Data segments with a noise floor above this threshold are rejected which tends to lower the noise floor of the test In order to reduce the possibility of obtaining an artificially low noise floor the minimum threshold level is limited Comment About Variations in the SNR Estimate The user needs to be aware that the SNR estimate has an inherent statistical variation due to the effects of random noise especia
15. on the hub Pull the green paper roller release lever forward until it snaps in place to disengage the roller W Slide the end of the paper O under the roller W it will come out from the front of the roller W Pull the paper end through the roller W until it extends about 3 inches above the roller W MD operating Instructions ERO SCAN Figure 30 Opening of the battery cover Paper Loading Path Paper Release Lever up position p SENE mE F Paper Rol Printer Mechanism Side Cutaway View Figure 31 Paper loading Figure 32 Printer with open cover Push the paper release lever D back Feed the loose end of the paper through the slot of the printer cover Close the printer cover Push the green button on the top of the printer to advance the paper The printer GEBA ero FOTO e Ola wpd 27 851946 4 04 01 MD operating Instructions EROs SCAN indicator light on the front of the printer will now flash green if the paper was properly installed Pressing the green button twice rapidly will print a test run 7 3 Attaching the Earti ps The MAICO ERO SCAN instrument comes with a box of disposable eartips that fit a variety of ear canal sizes The probe tip must have an eartip attached 8 g 9 before inserting it into an ear canal The eartip kit has 12 different size earti ps that p E B 8 are colour coded for easy selection The determination of the appropri
16. tests press the left 9 or right amp Figure 55 arrow keys to change the menu to 50 It is recommended Save Mode that you go to the Test Results Clear screen described in chapter 7 6 2 to clear any previous memory locations after you first select this option When the MAICO ERO SCAN unit has a full memory 50 saved tests it will not allow any further testing At this point either the results g SAYE LZR TESTS CHANGE HEXT must be printed or they must be cleared from memory MENARI Upon saving test number 45 the message shown in figure 56 is displayed and the red ERROR light amp appear At this point five more tests can be stored Press CONTINUE Message after 44 to proceed with testing When 50 tests are saved select stored tests FULL NERT Figure 56 TEST from the Main Menu the display will ask if you p want to clear all 50 results Note You may print or download the saved results at this time If you choose CLEAR all 50 tests will be deleted and the test numbers will start again at 1 The MAICO ERO SCAN unit figure 57 will ask to verify your decision to erase all stored tests To ea 30 print select Main Menu turn on the printer and set the instrument on its cradle All stored tests will be printed MEMORY FULL CLEAR DONE GEBA ero FOTO e 01a wpd 34 851946 4 04 01 MD operating Instructions ERO SCAN 7 7 7 Minimum DP Amplitude Press the NEXT button to enter this menu
17. 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 Figure 11 The External Probe GEBA ero FOTO e 01a wpd 14 851946 4 04 01 ID operating Instructions ERO SCAN 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 SSCAN 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 6 0 0 The MAICO EROeSCAN instrument uses four buttons to control all functions of the instrument These buttons are arranged in a directional cursor format The 12 18 PM arrows on the keys left 9 right Sup 9 down 9 correspond to the arrows that are used on the screen The screen will indicate which button to pus
18. until another test is completed NOTE The MAICO ERO SCAN instrument automatically prints test results stored in memory each time the instrument is placed in the cradle If the instrument is set to the L R print mode only the most recent test results for each ear will be printed If it is set to the 50 print mode the printer will print all tests stored in the MAICO ERO SCAN memory For ease of record keeping it is recommended that you print test results after each patient The MAICO ERO SCAN instrument can be configured to store up to 50 tests in memory before printing See the chapter 7 6 for instructions to save more than two tests in memory 5 9 Test Technique ERO SCAN instrument especially for newborns and infants Experience with existing OAE systems suggests that it may take up to three months to become As with other otoacoustic emission test instruments f there is a technique to learn when using the MAICO A r completely proficient at screening newborns with ea a emissions When testing a newborn or infant with the MAICO ERO sSCAN instrument the following suggestions tie ze might be helpful The newborn has to be relatively quiet az and calm it is usually preferred for the infant to be WA asleep A pacifier may be used to calm the newborn however sucking will add noise to the test and decrease Figure 26 Newborn test with pacifier the likelihood of a passing result When testing
19. we will drop our liability if these checks are not done The user of the instrument should perform a subjective instrument check once a week For your own security you should copy the printout of the test and store it in your files 63 851946 4 04 01 MD operating Instructions ERO SCAN Certificate of Conformity We MAICO Diagnostic GmbH Rohrdamm 7 D 13629 Berlin Germany certify that the product MAICO ERO SCAN starting with serial number 181 4001 is produced according to the Medical Directive 93 42 EEC V U Feel Berlin April 2001 U Ledworuski Head of quality department QW 031 2 04 01 GEBA ero FOTO e 01a wpd 64 851946 4 04 01 MD operating Instructions ERO SCAN Specifications are subject to change MAICO MAICO Diagnostic GmbH Rohrdamm 7 D 13629 Berlin Telefon 030 38 62 94 06 Telefax 030 38 62 94 99 email EXPORT maico diagnostic de internet www maico diagnostic de 65 851946 4 04 01 GEBA ero FOTO e Ola wpd MAICO EROeSCAN Hand held unit Eartip 2 Probetip 3 Control and display area Housing Tero acan NM Error LED red Eum EA mM Test LED yellow F 2 Ready LED green Graphical LCD display 9 Left button Down button W Up button 2 Right button 9 Monitor phone connector Drawer battery compartment amp Contacts for data transfer Plug for external probe Geo a0 2 DDO MAICO ERO SCAN External probe Connector to hand held unit Hou
20. within an acceptable range and is stable over time the unit proceeds to the calibration phase For DPOAE The calibration phase automatically measures the response obtained from a sequence of calibration tones and pu calculates the voltage needed to obtain the desired RETEST pressures If one or more of the desired pressures cannot tL be obtained the instrument stops operation and displays E an error message see figure 81 A successful calibration reached leads to the actual test phase The test phase consists in measuring the response obtained from the pairs of test frequencies f1 f2 applied to the receivers Two receivers are used with each receiver generating one frequency in order to reduce intermodulation distortion Frequency domain estimates of the actual P1 P2 distortion DP and noise floor NF are obtained via the discrete Fourier transform with a bin resolution of approximately 31 Hz The NF estimate is obtained by averaging the power in the 4 closest 2 bins to the DP bin For TEOAE The calibration phase automatically measures the peak pressure obtained from a sequence of clicks and calculates the voltage required to obtain the target peak pressure If the desired peak pressure cannot be obtained the GEBA ero FOTO e 01a wpd 50 851946 4 04 01 MD operating Instructions ERO SCAN unit will use the maximum voltage The test phase consists of measuring the response obtained from repeated sequences
21. Hz 2 0 to 6 0 kHz 2 4 6 kHz 2 2 5 3 4 5 6 kHz 1 5 to 6 0 kHz 1 5 3 6 kHz 1 5 2 3 4 5 6 kHz The default mode is 2 0 to 4 0 kHz Press the CHANGE keys or lt to select an option and the NEXT key O to exit 7 8 4 Setting the Level of the Primary Tones The intensity of the primary tones P1 P2 may be changed Pipinus to any level between 40 dB and 65 dB The level P1 CHANGE will change in 1 dB increments by pushing the left or RENE right amp arrow keys figure 67 a 1 The default mode is P1 65 P2 55 Press the NEXT key to set the level of P2 as for P1 figure 68 PRESSURE P2 55 Figure 68 Level of test tone 2 GEBA_ero_FOTO_e 0la wpd 3 7 851946 4 04 01 MD operating Instructions ERO SCAN 7 8 5 Setting the Averaging Time The Averaging Time can be changed to several different lengths The Averaging Time will have a large impact on the time required to perform the test and on the signal to noise AVERAGING ratio SNR A 0 5 second average for 6 frequencies would TIME 2 produce a test in about 4 seconds A 2 second average for Cee z 6 frequencies would produce a test in about 14 seconds Figure 69 The possible settings for the Averaging Time are as Averaging time follows 0 5 sec 1 0 sec 2 0 sec 4 0 sec The default setting is 2 seconds Press the CHANGE keys or lt to select an option and the NEXT key O to exit 7 8 6 Settin
22. ILITY OF SNR 7 db 50 LX AT ONE FREQUENCY 40 S ONE IN 100 PROBABILITY 90 OF SNR 7 dB AT 8 OF 6 FREQUENCIES 20 w BINOMIAL 10 0 10 5 0 5 10 15 20 SIGNAL RE NOISE IN ADJACENT BANDS dB CUM DIST 3 FREQ DISTRIBUTION CUM DISTR 1 FR CUM DISTR 2 FR Figure 93 Probability of Missing Mod Severe HL GEBA ero FOTO e 01a wpd 59 851946 4 04 01 MD operating Instructions ERO SCAN Pass Refer Criteria for TEOAE The same basic principles that underlie DPOAE Pass Fail criteria underlie TEOAE Pass Fail criteria In the case of transients requiring SNR of 4 dB at any 3 out of the 6 test frequencies drops the probability of passing an ear with a significant hearing loss to less than 196 Note The SNR limits for transients are lower than the corresponding limits for distortion products primarily because the traditional noise calculation used in TEOAE measurements and in the EROeSCAN instrument gives a 3 dB lower SNR than the calculation used for DPOAEs Without that difference the numerical SNR value for a PASS with the two methods would be quite similar The MAICO ERO SCAN uses a novel noise rejection algorithm patent pending that permits accurate DPOAE and TEOAE measurements in background noise and babble as high as 55 65 dB SPL A weighted Briefly explained use of available memory in the EROeSCAN processor permits a post hoc statistical analysis that identifies those samples whose retention would
23. PiP2 DP NF SNR 41 I 206050 5 TE The software version number 236050 amp Rod The averaging time used for Q 3 06050 6 this test 3 56050 9 10 19 406050 5 8 13 The mode selected for this F2 MENT test 2 08888 HEEL HE 2008 235 HMM rnnttt 00 7 7 l3 2 GHI nnns 44 3 08 EHE ee Seat 122222220 02022221 The pressure levels of f1 and moto m i F2 f2 respectively A48 AG amp O 8 10 The f2 frequency Level dB NF DP The level of the emission in Bio Pass The noise floor in dB The signal to noise ratio DP Figure 28 Full result printout level minus the noise floor A P indicates that the signal to noise ratio for the test was equal to or above the SNR criterion The thick bars indicate the noise floor in dB The small bars indicate the emission level in dB GEBA ero FOTO e 01a wpd 24 851946 4 04 01 MD operating Instructions ERO SCAN 6 3 Understanding the TEOAE Printed Results Each test will generate its own printout Described below is the FULL printout text or graph printouts will be abbreviated 10 11z The test number The ear selected The time and date of the test based on the setting of the internal clock The software version number The averaging time used for this test The mode selected for this test The frequency band The peak pressure level The level of the emission in OB eas The noise floor in dB
24. ROeSCAN If you have problems or have ideas for further improvements please get in touch with us Simply call Your MAICO team GEBA ero FOTO e Ola wpd 2 851946 4 04 01 MD operating Instructions ERO SCAN 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 AN The MAICO EROeSCAN instrument probe tip must not be inserted into any ear at any time without a disposible eartip properly affixed Precautions READ THIS ENTIRE MANUAL BEFORE ATTEMPTING TO USE THIS UNIT e Use this device only as described in this manual e Use only the disposable earti ps designed for use with this instrument e Never insert the probe tip into the ear canal without affixing an earti p e The eartips are disposable and for single patient use only Do not clean or reuse earti ps e 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 Remove the batteries from the instrument if it will not be used for 4 weeks or more e Do not immerse the unit in any fluids See the Cleaning section of this manual for proper cle
25. T 8 g 30 59 heo tk w 10 1k T E ak Si th Frequency Hz F Frequency IMT Figure 91 Sound Source Frequency Figure 92 System Distortion Noise Response nominal nominal GEBA ero FOTO e Ola wpd 5 7 851946 4 04 01 MD operating Instructions ERO SCAN Pass Refer Criteria for DPOAE The decision that a DPOAE exists is based on detecting a signal whose level is significantly above the background noise level This requires a statistical decision since the random noise level in the DPOAE filter channel can be expected to exceed the average of the random noise levels in the 4 adjacent filter channels used as the reference for comparison roughly half the time Extended measurements of the noise distributions in both the DPOAE filter channel DP level and the RMS average of the 4 adjacent channels N level indicate that the signal to noise ratio the difference between DP and N has a standard deviation of 5 5 dB As shown in the figure below this implies a 1096 probability of seeing a 7 dB SNR simply from the variability of the noise levels in the 2 filter sets Requiring an SNR of 5 dB in 3 out of 3 frequencies drops the probability of passing an ear with significant hearing loss to 196 or less In theory a pass criterion of slightly higher than 4 dB should be adequate but examination of our cumulative distribution SNR data suggested choice of a more conservative number Note By the binominal distribution two of three fr
26. The printout values are rounded up to the nearest integer and are shown as DP 5 NF20 SNR 5 which seems to be an error since no P appears but Is in fact correct Asimilar apparent problem can occur for the PASS criterion If the PASS criterion is 5 dB while the actual SNR 4 9 the printed value for the SNR will be 5 but a P will NOT be printed as shown in figure 24 Again the PASS criterion is based on the full precision of the results and not the rounded values that are printed The full precision value for the SNR must be equal to or higher than the PASS criterion 5 dB in this example for the P to be printed GEBA ero FOTO e 01a wpd 26 851946 4 04 01 7 Quick reference guide 7 1 Battery installation The MAICO ERO SCAN instrument uses 4 AA UM 3 R6 Alkaline batteries Open the battery compartment by sliding the battery panel down and install the batteries as indicated on the battery label Once the batteries are correctly in place slide the panel back onto its tracks to close the battery compartment 7 2 Changing printer paper Open the cover of the printer by pulling up and back Orient the paper roll so that the paper will feed from the bottom of the roll see Figures 31 and 32 Place the roll of paper into the printer by holding the white paper holder lever back against the case Allow the lever to slide back so that it fits onto the hub on the paper roll The paper roll should move freely
27. a newborn gently pull down and back on the pinna to GEBA ero FOTO e 01a wpd 20 851946 4 04 01 MD operating Instructions ERO SCAN straighten out the ear canal Prepare the MAICO ERO SCAN unit by turning on the device selecting the test ear and eartip It is very important to select the eartip and push the arrow key which selects the test ear before placing the MAICO ERO SCAN instrument into the newborn s ear canal Pushing the button after the eartip is in the ear canal may startle the baby and will cause a noisy test result Gently place the probe tip into the infant s ear canal using a cone shaped or small green or yellow mushroom shaped eartip The cone shaped eartips tend to insert deeper down into the ear canal than the mushroom shaped eartips Warming the eartips prior to insertion helps to keep the baby calm Deeper insertion into the ear canal allows for the measurement of larger emissions due to the reduced ear canal volume The small green and yellow mushroom shaped eartips can also be used however the selected eartip should enter the ear canal rather than just sitting flush with the ear canal opening 5 10 Noise Sources When the noise level exceeds the noise rejection limit of the instrument the red ERROR light will appear The ERROR light will usually appear while testing The light will appear infrequently if the noise level in the ear canal is low and it will appear more often if the noise level i
28. aning procedures e 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 e Use and store the instrument indoors only Do not expose this instrument or its accessories to temperatures below 40 F 4 C or above 100 F 38 C or to relative humidity of more than 75 e Do not attempt to open or service the instrument Return the instrument to the manufacturer for all service Opening the instrument GEBA ero FOTO e Ola wpd 3 851946 4 04 01 MD operating Instructions ERO SCAN case will void the warranty e Do not operate the printer if the power supply has a damaged cord or plug See the instructions on the following page e Do not expose the printed results to sunlight or heat Printing on thermal paper fades with exposure to light or heat e 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 AN 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
29. arrow key in the Reset to le RESET default menu Figure 61 will return the instrument settings DONE to their original factory settings Note This does not affect the Custom settings Figure 61 Reset to default GEBA ero FOTO e 01a wpd 35 851946 4 04 01 MD operating Instructions ERO SCAN 7 8 Advanced Options for DPOAE Testing The Advanced Options menus permit modification of the test stimuli and measurement values and should be changed only by qualified personnel usually the administrator If you are not familiar with the use of these variables do not attempt to change the protocols Changes to any of these characteristics may yield test results that differ from those obtained in other test modes The MAICO EROeSCAN instrument comes with pre programmed settings for the DP and DP Custom protocols See Chapter 11 for the settings of these custom protocols Custom settings are saved in the non volatile memory so the settings will be retained even when changing batteries 7 8 1 Instructions For Changing Test Protocols 1 Go to the Main Menu figure 62 Press the DOWN arrow key once CHANGE is displayed figure 63 2 Now hold the DOWN arrow key for 3 seconds until the green Ready LED turns off If you push the DOWN Figure 62 arrow key without holding it for 3 seconds you will zd scroll through date and time etc rather than accessing the displays that allow you to make changes to the custom proto
30. ate eartip b size should be made by persons with proper training and experience Figure 33 Box with eartip set Figure 34 Different eartip sizes The eartip must seal the ear canal The best test results are obtained when the eartip is inserted deeply into the ear canal instead of flush with the ear canal opening Caution must be taken however to ensure that the eartip does not extend too deeply into the ear canal Use only the eartips approved for use with the instrument Ordering information can be found in chapter 11 or inside the earti p box he earti ps are disposable and should be replaced after each patient Do not attempt to clean or reuse these earti ps After selecting an eartip push it onto the probe tip until it is flush against the base of the probe tip The sound outlet tubes on the probe tip are recessed to minimize the likelihood of clogging If the probe tip does become plugged or clogged it must be replaced See the following section Probe Tip Replacement for further information To remove the eartip grasp the eartip at the base and GEBA_ero_FOTO_e 01a wpd 28 851946 4 04 01 MD operating Instructions ERO SCAN twist it while pulling it straight off the end of the probe ti p 7 4 Probe Ti p Replacement The probe tip should be replaced when it becomes clogged Four replacement probe tips are included Nm this instrument Do not attempt to clean the probe tip the probe tips are disposa
31. be measured reliably above 4 kHz GEBA ero FOTO e Ola wpd 8 851946 4 04 01 MD operating Instructions ERO SCAN 4 Getting started 4 1 Unpacking your instrument Your MAICO EROeSCAN is carefully inspected and packed for shipping 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 1 MAICO ERO SCAN Hand held Unit P EC Oo eT RL chore arin nk kn na all Teen E MN UR v b Printer Power Sup et mama Rae AN 1 vite Ceng Qh NN GEBA ero FOTO e Ola wpd 9 851946 4 04 01 MD operating Instructions ERO SCAN T Headphones 1 Kit with 156 Earti ps 12 sizes A Probe
32. ble and must be replaced when they become clogged See the Replacement Parts section at chapter 11 Toreplace the probe ti p squeeze the tabs as shown in figure 35 The tabs Figure 35 Removing the probe tip should audibly snap off the probe assembly Pull the probe tip directly off the probe and discard it Obtain a replacement probe tip and orient the tip as shown in figure 36 The probe tip will only fit on one way be careful not to force the tip in place Push the tip directly down onto the probe Once the probe tip Is in place on the probe push firmly downward on the top of the tabs one at a time until a click is heard Figure 36 Replacing the probe tip Tug lightly on the probe tip to verify that the tip is securely attached GEBA_ero_FOTO_e 0la wpd 29 851946 4 04 01 MD operating Instructions ERO SCAN 7 5 Probe Ti p Replacement for the external probe The probe tip should be replaced when it becomes clogged Four replacement probe tips are included with this instrument Do not attempt to clean the probe tip the probe ti ps are disposable and must be replaced hen they become clogged Figure 37 Release the probe tip See the Replacement Parts section at chapter 11 To remove Use 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 remote probe until each tab is released Figure 37 Slide the probe tip o
33. cols 3 The next display you see is MODE SET figure 64 Use Change menu the LEFT or RIGHT 2 arrow keys to select DP Custom 4 Hold the DOWN arrow key again for 3 seconds until the green Ready LED turns off If you do not hold it for 3 seconds you will return to the Test Results Clear screen Now you will be able to scroll through the other characteristics Number of Frequencies Frequency Range P1 and P2 Levels Averaging Time PASS SNR Level and Number of Frequencies for PASS and make changes as 12 35 L TEST R SETUP Feb 26 00 12 35 CHANGE TEST MODE DP Custom eCHRNGE NEXT Moge set menu GEBA ero FOTO e 01a wpd 36 851946 4 04 01 MD operating Instructions ERO SCAN desired by using the LEFT 9 or RIGHT 2 arrow keys 7 8 2 Selecting the Number of Test Frequencies There are two options for the number of frequencies to be tested These options are as follows 3X1 3 frequencies 6 X 1 6 frequencies Figure 65 Number The default mode is 3 frequencies Press the CHANGE keys sn aa or lt to select an option and the NEXT key to exit OF FREG 3 CHANGE NEXT 7 8 3 Selecting the Frequency Range FREQ RANGE There are three options for the frequency range to be 2 8 4 8 tested T pies 2 Figure 66 These options are as follows Frequency range Frequency Range 3 Frequency Test 6 Frequency Test 2 0 to 4 0 kHz 2 3 4 kHz 2 2 3 2 6 3 3 5 4 k
34. efects in material and workmanship for a period of one year from date of delivery of the instrument to the original purchaser The instrument may be repaired only by your dealer or by a service centre recommended by your dealer We urgently advise you against attempting to rectify any faults yourself or commissioning non experts to do so In the event of repair during the guarantee period please enclose evidence of purchase with the instrument In order to ensure that your instrument works properly it should be checked at least once a year This check has to be carried out by your dealer Send the device to your dealer or to a service centre authorized by your dealer Please also include a detailed descri ption of the faults In order to prevent damage in transit please use the original packing if possible when returning the instrument GEBA ero FOTO e 01a wpd 62 851946 4 04 01 MD operating Instructions ERO SCAN 13 Safety Regulations 13 1 Electrical Safety 13 2 Measuring security 13 3 Device control GEBA ero FOTO e Ola wpd The OAE Test system MAICO ERO SCAN isa battery driven low voltage instrument The instruments are not intended for operation in areas with an explosion hazard To guarantee that the instrument works properly it has to be checked at least once a year The service and calibration must be performed by an authorized service centre In accordance with the regulations of the EU medical directive
35. ents Place an earti p as far down as possible on the probe ti p Turn on the MAICO EROeSCAN instrument by pressing the large down arrow button O Select the test ear by pressing the left 9 or right arrow key Insert the eartip deeply into the patient s ear canal to obtain a seal When a seal is obtained the MAICO EROsSCAN instrument will automatically begin Figure 4 Keys GEBA_ero_FOTO_e 01a wpd 11 851946 4 04 01 ID operating Instructions ERO SCAN the test by first calibrating and then testing emissions The red ERROR LED 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 When testing is completed on both ears turn the printer on by pressing the green button on top and Figure 5 Testing place the hand held unit on the cradle The most recent test results for both ears will automatically print out Figure 6 Printout of test result GEBA_ero_FOTO_e 0la wpd 12 851946 4 04 01 MD operating Instructions ERO SCAN 4 5 Installing the optional external probe Remove the protective cover of the external probe plug at the top of the MAICO ERO SCAN using a tool or the fingernail see figure 7 Turn off the MAICO ERO SCAN and put the external probe connector 2 into the plug on the top m Figure 7 of the MAICO EROSSCAN figure 8 The Pe
36. equencies at gt 8 4 dB or three of six frequencies at gt 7 dB should also ensure less than 1 probability of passing a moderately severe hearing impaired infant Preliminary MAICO ERO SCAN trials with newborns indicate that the tester s technique is the single most important variable in the pass rate on normal hearing infants Some testers pick up the technique see Operating Instructions section page 10 with only a couple of days practice producing pass rates comparable to those for other DPOAE equi pment they have used for months other testers need longer Occasional claims of extraordinarily low probabilities of missing an ear with hearing loss appear to be based on poor statistics As discussed by Gorga Mayo Clinic Teleconference 1998 verifying a 99 796 accuracy would require testing hundreds of thousands of babies with a given system Since the incidence of significant hearing loss is roughly 2 per 1000 Thus to demonstrate that only 3 babies out of 1000 GEBA ero FOTO e 01a wpd 58 851946 4 04 01 MD operating Instructions ERO SCAN NUMBER OF OCCURRENCES with hearing loss were missed would require follow up testing on 500 000 babies To our knowledge no one has performed such tests to date PROBABILITY OF MISSING MOD SEVERE HL SNR DISTRIBUTION METAL CAVITY 100 904 ONE IN 100 PROBABILITY OF SNR gt 5 dB AT 3 OF 3 FREQUENCIES 80 L OR gt 8 4 dB AT 2 OF 3 FREQUENCIES BINOMIAL DIST 70 ONE IN TEN 60 N PROBAB
37. ff the front of the probe and Figure 38 discard Figure 38 Remove the probe tip To replace 1 Align a replacement tip with the front of the probe Figure 39 The tip will only fit in one direction If the tip does not fit securely on the probe remove the probe ti p and reorient it 2 Press lightly on the tabs to snap them into place The tabs should be flush with the outside of the probe iion t Figure 40 NOTE If the probe tip is not inserted completely the e MAICO EROeSCAN will not perform a test Figure 39 he new probe tip Figure 40 Fastening the probe tip GEBA ero FOTO e 01a wpd 30 851946 4 04 01 MD operating Instructions ERO SCAN 7 6 Setting the built in clock TM When the MAICO EROeSCAN test instrument is first IDEM used the correct date and time will need to be set on its internal clock The date and time are listed on the test printout as month day year e g Feb 26 99 The clock should be set prior to testing as changing it after tests are saved will not change the date on the printout i e whatever date was previously in memory will be the date on the printout Seasonal time changes such as Daylight Savings Time will also require resetting the clock Figure 42 Display If the instrument s batteries are empty and are replaced 9f actual time date within approximately one hour the display as shown in figure 41 may appear If this message appears set time Feb gt and da
38. g the Pass SNR Level In order to provide a PASS REFER determination for f PASS each test the PASS SNR must be set This number refers SNR 5 to the number of decibels that the DPOAE signal must be SEE EN above the noise to be considered a PASS at that frequency The limits for the PASS SNR are 3 dB to 10 Figure 70 i Pass SNR level dB Pressing the left or lt right W arrow keys will increase or decrease the requirement This requirement is used in combination with the number of frequencies discussed below to determine an overall PASS REFER for each test The default setting for the PASS SNR is 5 dB Press the CHANGE keys or 2 to select an option and the NEXT key to exit 7 8 7 Setting the Number of Frequencies for a PASS The number of frequencies for determining a PASS can be set from O to 6 If the setting is on 0 then no indication 3 FREGS FOR PRSS of PASS REFER will be made This setting is used in CERE conjunction with the PASS SNR to set the criteria for the Figure 71 overall test PASS REFER indication For example if Frequencies for the PASS SNR is set to 5 dB and the number of pass frequencies for PASS is set to 3 then the test must contain at least 3 frequencies where the emission is at least 5 dB above the noise to indicate GEBA ero FOTO e 01a wpd 38 851946 4 04 01 MD operating Instructions ERO SCAN a PASS The number of fre
39. h by showing the appropriate arrow NOTE The gt up key will always bring the instrument back to either the previous menu or the Main Menu The 2 up key will also turn the unit off when the 9 D 12 instrument is at the Main Menu Figure 12 Control buttons and displays 5 3 Turning On the Instrument To turn on the MAICO ERO SCAN instrument press the large down key located below the instrument s display screen 9 Three small lights red OPERATING MODE DP yellow and green will appear for a Figure 13 Figure 14 short moment just above the display Toren Start display screen The green ready light will remain on On the display the text shown in figure 14 will appear shortly when DPOAE is set or selected If GEBA ero FOTO e 01a wpd 15 851946 4 04 01 ID operating Instructions ERO SCAN 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 12 35 date and time settings If there are no date time errors z LL TEST R detected the Main Menu Figure 15 will appear on the l SETUP display Figure 15 NOTE If this is the first time the Marco Man 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 EROeSCAN instrument has an automatic sh
40. he minute menu figure ecc 47 and use the LEFT 9 or RIGHT 2 buttons to select DONE the correct minute When the correct minute is selected pressing the DOWN key O will return you to the Main Figure 47 Changing vi of the minute enu The time and date changes are automatically saved 7 7 Changing Instrument Settings The MAICO EROeSCAN instrument allows the user to change many of the instrument s settings or functions These settings include the Test Mode DP and DP Custom or TE and TE Custom combined instruments allow the 12 35 L TEST R SETUP choice from all four modes Clearing Test Results Auto P A Shutdown Time Headphone Level Minimum Amplitude Level Save Mode Clock Mode Language and Reset to ji ad default Settings To access the menus to change these CHRHGE functions press the SETUP key from the Main Menu see figure 48 to enter the CHANGE menu see figure 49 Figure 49 At this menu hold down the CHANGE key for three Change Menu seconds until the Ready light green LED turns off Releasing the key will then access the menus to change the instrument settings 7 7 1 Test Mode The MODE SET menu figure 50 allows the user to change g the test protocol The Test Modes that can be selected include either DPOAE and DP Custom or TEOAE and TE Custom All protocols in the unit come with preset test values Chapter 11 which can also be customized using Figure 50 the Ad
41. 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 e 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 e Do not short circuit the battery contacts This could cause burns or a fire GEBA ero FOTO e Ola wpd 4 851946 4 04 01 MD operating Instructions ERO SCAN S cd 9 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 ri
42. lly when no emission is actually present If a test is performed with the instrument s probe placed in a test cavity it can be shown theoretically that the SNR will be higher than 6 dB approximately 7 times out of 100 This is not a limitation of the instrument but a fundamental property of the method used to estimate the SNR in all emission testing In order to reduce the occurrence of this false emission the instrument limits the minimum value of NF which has the effect of reducing the SNR for tests that have a low noise floor As the noise level of the test increases the user will notice that more false emissions will appear which is to be expected GEBA ero FOTO e 01a wpd 51 851946 4 04 01 MD operating Instructions ERO SCAN Program Flowchart OPERATING MODE DP RE 18 35 AM L TEST R v SETUP NOISE R d iti IER Wi EE Gi d spells sesso eese Figure 82 Program flowchart GEBA ero FOTO e 01a wpd 52 851946 4 04 01 m Operating Instructions ERO SCAN Setup Flowchart DATE TIME SYSTEM DPOAE TEOAE MENU MENU MENU MENU TEST MODE Feb 28 81 18 35 AM CHANGE eo RESULTS e CLEAR gt NEXT PRESSURE P1 65 CHANGE NEXT PRESSURE P2 55 A SIUE SE TSRVE L R TESTS Press and hold DOWN Arrow for three seconds to enter next menu Figure 83 Setup flowchart GEBA e
43. ly when it becomes clogged For Probe ti p replacement see chapter 7 4 for the built in probe or chapter 7 5 for the external probe GEBA ero FOTO e 01a wpd 44 851946 4 04 01 MD operating Instructions ERO SCAN 10 Trouble shooting If you should find that your instrument is no longer working properly during a test run please check the following points 10 1 Problems and Solutions 1st Problem Instrument does not turn on Solutions The DOWN key must be pressed for a full second Check that the batteries are installed correctly Install new batteries 2nd Problem The test will not start even though the instrument is in an ear canal Solutions Try a different size earti p Verify that the earti p is sealed in the ear canal via error messages Reseat or replace the probe ti p If the patient has a PE tube refer to chapter 5 5 1 3st Problem The printer doesn t print Solutions Press the green button on the printer and try again If the printer light doesn t turn on plug in the printer power supply to charge the battery Note You will have to wait a period of time before printing will occur even when AC power is provided Verify that the printer battery pack is installed correctly If paper comes out of the printer but there is no text on the paper then the paper is in backwards Remove the paper and reinstall the paper so that it feeds from the bottom of the roll Check that the printer cable is correctly attached to the
44. n the ear canal is high Otoacoustic emissions are very low level sounds that must be measured by the microphone in the probe Any noise in the ear canal at the time of testing can mask this emission This noise can come from a variety of sources The largest source of noise can come from the patient This biological noise can come from the patient movement coughing sucking talking etc The patient must be calm and should not move or talk Ambient noise in the testing environment can also be a large source of noise during the test GEBA ero FOTO e 01a wpd 21 851946 4 04 01 MD operating Instructions ERO SCAN A properly sealed eartip can block a large amount of this noise but performing the testing in a relatively quiet environment is recommended Another source of noise is the tester The MAICO ERO SCAN instrument has an isolation mechanism that will isolate most of the tester s hand movement and associated noise from the probe but the tester should hold the instrument as steady as possible GEBA ero FOTO e 01a wpd 22 851946 4 04 01 MD operating Instructions ERO SCAN 6 Interpreting test results 6 1 Understanding the Display The display on the MAICO ERO SCAN test instrument will indicate the results of the test with a graphical display The display will be generated and shown during the test and can be reviewed after the test is completed The display might differ depending on the settings used for the test
45. na Cover connector O will fit only in one direction The arrows on eeN the connector should face the display amp on the E MAICO ERO SCAN Turn on the MAICOERO SCAN TheyellowTEST light on the display will light shortly indicating the MAICO ERO SCAN has detected the presence of Figure 8 the external probe Disconnect and reinsert the connector Cannon ai if the yellow light is not seen 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 fully onto the probe tip see Figure 9 The external probe uses the same disposable eartips as the MAICO EROeSCAN probe Place the eartip Never use the probe without an eartip installed Use the Correct Placement shirt clip on the external probe housing to secure the of the Eartip probe to clothing or bedding Check the ear canal for cerumen or vernix before inserting the probe Turn on the MAICO EROeSCAN and select the ear to be tested 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 Figure 10 Prope Correct inserted External Probe GEBA_ero_FOTO_e 0la wpd 13 851946 4 04 01 MD operating Instructions ERO SCAN The AUTO START function automatically begins the test when
46. nt 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 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 tip The disposable eartips 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
47. quencies for PASS should also be based on the number of frequencies being tested Setting the number of frequencies for PASS to 4 when only 3 frequencies are being tested would result in every test being labelled as a REFER To disable the PASS REFER indication set the number of frequencies for PASS to O The default setting for the number of frequencies is 3 Press the CHANGE keys or 2 to select an option and the NEXT key to exit 7 8 8 Save Protocol Once all of these settings have been determined for the SRVE customer program these settings can be saved by selecting PROTOCOL the left or right arrow keys Figure 72 This will 1f WE save the selected settings as the customer program selected and will be stored in this customer program until Figure 72 Save Protocol new settings are selected and saved GEBA ero FOTO e 01a wpd 39 851946 4 04 01 MD operating Instructions ERO SCAN 7 9 Advanced Options for TEOAE Testing The Advanced Options menus permit modification of the test stimuli and measurement values and should be changed only by qualified personnel usually the administrator If you are not familiar with the use of these variables do not attempt to change the protocols Changes to any of these characteristics may yield test results that differ from those obtained in other test modes The MAICO EROeSCAN instrument comes with pre programmed settings for the TE and TE Custom pro
48. r in each of the Figure 22 Test in progress frequency bands TEOAE Testing is completed when the green READY light C2 is illuminated Both the tester and patient should remain as still and quiet as possible until the green light 2 turns on The graphic display is explained in chapter 6 ESS Interpreting Test Results 5 7 Reviewing the test results LEFT EAR When testing is completed a display similar to figure 23 Poss will appear L TEST R gt REVIEW as soon as the test is complete The results will be saved even if the unit turns off or the batteries are temporarily Figure 23 Test result removed This screen again indicates the test ear and further gives the results of the GEBA ero FOTO e 01a wpd 18 851946 4 04 01 ID operating Instructions ERO SCAN test PASS on the screen indicates the patient passed the screening REFER indicates that the patient did not pass the screening NOISY indicates that excessive noise was present during the test The tester can determine from the display whether the test should be repeated To review the results push the down arrow key to return to the bar graphs After reviewing the results again push the down arrow key to return to the Main Menu 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
49. ro FOTO e 01a wpd 53 851946 4 04 01 MD operating Instructions ERO SCAN Standard accessories ERO SCAN Hand held unit 1 Cradles arre a a 1 Al ONE s ie ro ersscec NA AA Deci 1 Power supply E Printer Cable ooooooooo Y 1 Head On Eee Ba EKA YEN Q 1 PENCE DP SBE cde e sedare xs 4 PRO DE DS en mel BA nares kl UD aa lane ADi 4 Alkaline AA Batteries Already installed 1 Printer paper roll Already installed Optional accessories 4 1 External probe Part No 80 11 27 ba 1 Carrying case heavy duty Part No 80 10 69 1 GEBA ero FOTO e 01a wpd 54 851946 4 04 01 MD operating Instructions ERO SCAN Disposables 1 1 1 1 1 1 1 1 1 1 1 1 1 Printer paper roll Set 4 Pcs Probe tips Eartip 3 mm yellow Eartip 4 mm red Eartip 5 mm blue Earti p 6 mm green Earti p 7 mm yellow Earti p 8 mm red Earti p 9 mm blue Eartip 10 mm green Eartip 11 mm yellow Eartip 12 mm red Eartip 13 mm blue Eartip 14 mm green Eartip 15 mm yellow 11 mm 12mm 13 mm yellow red blue 7mm 8 mm green yellow red 3mm 4 mm yellow GEBA ero FOTO e 01a wpd red Figure 84 55 Eartips Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No Part No 14 mm green 9 mm blue 5 mm blue 70 50 77 1050 81 70 50 63 10 50 64 70 50 65 70
50. rument Trouble shooting Technical data Warranty maintenance and after sales service Certificate of conformity Front panel layout and rear panel connections GEBA ero FOTO e Ola wpd 1 851946 4 MD operating Instructions ERO SCAN Page O O J DWN 10 11 11 13 15 15 15 16 17 18 19 20 21 23 24 25 27 27 27 29 30 31 36 40 43 45 47 62 64 66 04 01 MD operating Instructions ERO SCAN 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 CE symbol according to Medical Directive 93 42 EEC In designing the MAICO EROe 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 ina 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 description of the position e g of controls displays and connections found again in the text will make it easier for you to learn how to operate the MAICO E
51. sing Probe tube Probetip Eartip MAICO EROeSCAN Cradle Contacts for data transfer Connnector for data transfer to printer or PC O Slots for cables MAICO ERO SCAN Printer D Printout paper Indicator LED LED orange charging LED green ready Power on button Cover Rechargeable battery pack D Connector MAICO EROeSCAN Printer cable e Printer cable 9 Cable connector for external power supply
52. sk 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 AN Ch YAN 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 GEBA ero FOTO e Ola wpd 5 851946 4 04 01 MD operating Instructions ERO SCAN 3 Description The MAICO ERO SCAN Otoacoustic Emission test instrument is a hand held device designed to provide an objective test of outer hair cell function through the measurement of Distortion Product Otoacoustic Emissions DPOAEs or Transie
53. t is used in combination with the number of frequencies discussed below to determine an overall PASS REFER for each test The default setting for the PASS SNR is 4 dB Press the CHANGE keys or 2 to select an option and the NEXT key O to exit AVERAGING TIME 64 e CHANGE NEXT GEBA_ero_FOTO_e 0la wpd 41 851946 4 04 01 MD operating Instructions ERO SCAN 7 9 5 Setting the Number of Frequencies for a PASS The number of frequencies for determining a PASS can f 3 FREQS be set from O to 6 If the setting is on 0 then no indication FOR PASS of PASS REFER will be made This setting is used in ic gt conjunction with the PASS SNR to set the criteria for the Figure 79 overall test PASS REFER indication For example if Frequencies for the PASS SNR is set to 4 dB and the number of pass frequencies for PASS is set to 3 then the test must contain at least 3 frequencies where the emission is at least 4 dB above the noise to indicate a PASS The default setting for the number of frequencies is 3 Press the CHANGE keys or lt to select an option and the NEXT key to exit 7 9 6 Save Protocol Once all of these settings have been determined for the g l SAVE customer program these settings can be saved by selecting PROTOCOL the left O or right arrow keys Figure 80 This will 4 pone save the selected settings as the customer program selec
54. te NEXT To change the time and date enter the SETUP by pressing Figure 43 qum the DOWN button at the Main Menu The display of the month will show the current date and time presently set in the Figure 41 Display of time date error Feb 26 00 12 35 CHANGE HONTH DAY unit e 26 4 If the time and date are correct press the gt UP key to NEXT escape back to the Main Menu If either the date or time is incorrect press the DOWN ix o i button to access the menu to change the month f Figure 43 SE Press the LEFT or RIGHT 2 keys to scroll forward or NEXT backward through the months You will see the abbreviated name for each month Figure 45 Changing When the desired month appears on the display press the of the year DOWN key to enter the day selection screen Figure 44 Pressing the LEFT or lt RIGHT keys will scroll through the days of the month After the correct day is selected press the DOWN key i Figure 46 Changing to enter the year selection figure 45 Pressing the Sena bou GEBA ero FOTO e 01a wpd 31 851946 4 04 01 MD operating Instructions ERO SCAN LEFT or RIGHT keys will scroll through the years When the correct year is selected press the DOWN key to enter the hour menu figure 46 Again use the LEFT or RIGHT 2 keys to set the correct hour Press the DOWN key to enter t
55. ted and will be stored in this customer program until Figure 80 Reset to default new settings are selected and saved GEBA ero FOTO e 01a wpd 42 851946 4 04 01 ID operating Instructions ERO SCAN 8 Recommended literature Audiometric Interpretation A Manual of Basic Audiometry Lloyd Lyle L and Harriet Kaplan Baltimore University Park Press 1980 Auditory Disorders A Manual for Clinical Evaluation Jerger Susan and James Jerger Boston College Hill Press 1981 Handbook of Clinical Audiology Katz Jack Baltimore William amp Wilkins 1994 Roeser s Audiology Desk Reference Roeser Ross J New York Stuttgart Thieme 1996 Auditory Diagnosis Silam Shlomo and Carol A Silvermann San Diego London Singular Publishing Group 1997 GEBA ero FOTO e 01a wpd 43 851946 4 04 01 MD operating Instructions ERO SCAN 9 Care and maintenance of the instrument Cleaning the instrument The instrument and its accessories may be wiped clean with a damp cloth using a mild antiseptic solution Take care not to put excessive pressure on the clear display window or allow any utensil to puncture the display window or keypad Do not allow any fluid to enter the device Do not immerse the instrument in fluids or attempt to sterilize the instrument or any of its accessories Maintenance The instrument requires no regular maintenance beyond routine cleaning and battery replacement The probe ti p requires replacement on
56. the Frequency Range There are two options for the frequency range to be tested jy v These options are as follows CHANGE NEXT Frequency Range 6 Frequency Test 0 7 to 4 0 kHz 0 7 1 0 1 4 2 0 2 8 4 0 kHz Figure 76 1 5 to 4 0 kHz 1 5 2 0 2 5 3 0 3 5 4 0 kHz Frequency range The default mode is 0 7 to 4 0 kHz Press the CHANGE keys or lt to select an option and the NEXT key to exit 7 9 3 Setting the Averaging Time The Averaging Time can be changed to several different lengths The Averaging Time will have a large impact on the time required to perform the test and on the signal to noise ratio SNR A 4 second average would produce a test in about 7 seconds A 16 second average would produce a test in about 18 seconds The possible settings for the Figure 77 Averaging Time are as follows 4 sec 8 sec 16 sec 64 Averaging time sec The default setting is 64 seconds Press the CHANGE keys or 2 to select an option and the NEXT key O to exit 7 9 4 Setting the Pass SNR Level In order to provide a PASS REFER determination for FF each test the PASS SNR must be set This number refers to the number of decibels that the TEOAE signal must be above the noise to be considered a PASS at that frequency The limits for the PASS SNR are 3 dB to 10 Figure 78 Pass SNR level dB Pressing the left or right arrow keys will increase or decrease the requirement This requiremen
57. tions 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 pati
58. 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 EROeSCAN 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 Ola wpd 6 851946 4 04 01 MD operating Instructions ERO SCAN 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 Description 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
59. tocols See Chapter 11 for the settings of these custom protocols Custom settings are saved in the non volatile memory so the settings will be retained even when changing batteries 7 9 1 Instructions For Changing Test Protocols 1 Go to the Main Menu figure 73 Press the DOWN 12 35 a L TEST R arrow key 0 once CHANGE is displayed figure 74 SETUP 2 Now hold the DOWN arrow key for 3 seconds until Figure 73 the green Ready LED turns off If you push the DOWN Main Menu arrow key without holding it for 3 seconds you will g scroll through date and time etc rather than accessing the displays that allow you to make changes to the custom CHANGE protocols a 3 The next display you see is MODE SET figure 75 Use the LEFT or RIGHT 2 arrow keys to select DP Figure 74 Change menu Custom 4 Hold the DOWN arrow key again for 3 seconds until the green Ready LED turns off If you do not hold it for 3 seconds you will return to the Test Results Clear screen Now you will be able to scroll through the other Figure 75 characteristics Frequency Range Averaging Time PASS Mode set menu SNR Level and Number of Frequencies for PASS and make changes as desired by using the LEFT or RIGHT arrow keys Feb 26 00 12 35 TEST MODE TE Custom CHANGE NEXT GEBA_ero_FOTO_e 01a wpd 40 851946 4 04 01 MD operating Instructions ERO SCAN 7 9 2 Selecting
60. tteries Dimensions WxDxH 21x9x5 cm GEBA ero FOTO e Ola wpd 47 851946 4 04 01 MD operating Instructions ERO SCAN PRINTER SPECIFICATIONS Type Speed Operating Noise Weight Dimensions Power Supply Recharger Paper Battery Life Thermal dot matrix line printer gt 10 lines per second lt 50 dB SPL 630 g 1 4 Ibs including battery pack WxDxH 10x 15 5 x8 cm Ni Cad rechargeable battery pack Plug in transformer 12V 400mA 230V 50 Hz double insulated Calculator type thermal roll 2 25 wide Approximately 300 tests CRADLE SPECIFICATIONS Weight Dimensions 630 g 1 4 Ibs including battery pack WxDxH 7 5x19x10 cm Interface connector 9 pin RS 232 connector PROCESSOR SPECIFICATIONS Digital Signal Processor Motorola 56303 24 bit 66 MHz 3 3 V Storage Battery Backup CODEC Display Switches GEBA ero FOTO e Ola wpd 1 Mbit Flash EEPROM non volatile 0 1 F 5 0 V approx 24 hours 18 bit D A 18 bit A D 96 dB SNR typical 4 line x 10 character STN liquid crystal Membrane keypad 1 million actuation 48 851946 4 04 01 MD operating Instructions ERO SCAN Preset Test Protocols DPOAE Number of Frequencies Tested 3 Frequency Range 2 kHz to 4 kHz P1 Intensity of f1 in dB SPL 65 P2 Intensity of f2 in dB SPL 55 Averaging Time 2 seconds Pass SNR Signal to Noise Ratio 5 dB Number of passing Frequencies for Overall Test Pass 3 DP CUSTOM Number
61. u minutes have elapsed The Auto Shutdown time may be increased or decreased by pressing the CHANGE keys or lt The times available are 30 seconds 1 2 or 4 minutes Once you have made your selection press NEXT 7 7 4 Headphone Level The Headphone Level menu see figure 54 is next Using the headphones provided with the MAICO ERO SCAN instrument enables the examiner to listen to the calibration and test tones The headphone plug should be inserted into the jack at the bottom of the Figure 54 in Headphone level MAICO ERO SCAN instrument The headphones HEADPHONE LEVEL 5 amp CHANGE gt NEXT GEBA_ero_FOTO_e 0la wpd 33 851946 4 04 01 MD operating Instructions ERO SCAN may be used both as a learning tool and for real time monitoring of the ear canal during the test Press the CHANGE keys or 2 to change the volume level for the headphones The volume level may be set from 1 9 with 1 being the lowest volume level and 9 as the highest volume level The default value is 5 and should be suitable for most situations NOTE Changing the headphone volume will not change the intensity of the test tones that are presented to the patient 7 7 5 Save Mode Storing Test Results The Print Mode menu is shown in figure 55 The MAICO f ERO SCAN unit automatically stores only the most recent test result for each ear L R The unit has the capacity to store 50 individual tests To change the mode to save up to 50
62. utdown 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 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 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 2 65 dB Number of PASSing Frequencies for Test PASS 3 P2 Intensity of f2 55 dB The settings for TEOAE testing in the default mode are as follows Number of Frequencies Tested 6 Averaging Time 16 Seconds Frequency Range 1 kHz to 4 kHz PASS SNR Signal to Noise Ratio 4 dB Click Presentation Level 65 dB Number of PASSing Frequencies for Test PASS 2 3 GEBA ero FOTO e 01a wpd 16 851946 4 04 01 MD operating Instructions ERO SCAN 5 5 To Begin Testing To begin testing in the default
63. vanced Option menus Programming these custom Mode set protocols is described in the Advanced Options section in chapter 7 7 TEST MODE DP Custom eCHRHNGE NEXT GEBA_ero_FOTO_e 0la wpd 32 851946 4 04 01 MD operating Instructions ERO SCAN NOTE Units with both DPOAE and TEOAE capability will allow the user to choose between 4 modes DP DP Custom TE or TE Custom Pressing the left or right 2 arrow key will scroll through the available choices When the display shows the setting desired press the NEXT key O 7 7 2 Clearing Test Results Test Results Clear menu figure 51 allows the user to clear the test results stored in the unit without printing them Figure 51 Select the left or right arrow key to clear the Siegen results and select Yes 2 or No to verify clearing or not clearing the results figure 52 7 7 3 Auto Shutdown Time The Power Off menu see figure 53 refers to the Auto VERIFY CLEAR NO YES Shutdown time which controls how long the MAICO Figure 52 EROeSCAN instrument waits before shutting itself eee off after a period of inactivity It is not necessary to manually turn off the MAICO EROeSCAN unit The POWER OFF 2 MINUTES Automatic Shutdown feature is designed to prolong the CHANGE battery life of the instrument when it is not in use By TEX default the instrument automatically shuts off after 2 F 9ure 53 Power off men
64. y begin testing and the yellow TEST LED 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 17 851946 4 04 01 MD operating Instructions ERO SCAN 5 6 Auto Calibration and test 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 9 or right arrow key for 3 seconds until the green test light turns off Once the key is released the MAICO ERO SCAN will calibrate and test as described below CAL TEST demam 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 During calibration a series of tones will Figure 21 be presented to the ear canal to calibrate the levels of Calibration 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 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 o

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