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Operating Instructions MB 11 Classic

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1. MAICO Diagnostic GmbH MAICO Operating Instructions MB 11 Classic MAICO Diagnostic GmbH Salzufer 13 14 D 10587 BERLIN Tel 49 30 70714650 Fax 49 30 70714699 MAICO Table of Contents 1 Introduction 2 Important safety Instructions 3 Description 3 1 Auditory Brainstem Response ABR audiometry 3 2 The MB 11 Classic MA Operating Instructions MB 11 Classic lOO Oo W 3 3 Automatic Screening with the Auditory Steady State Algorithm 10 4 Getting started 4 1 Unpacking your instrument 4 2 Preparing the MB 11 for use 4 3 Getting familiar with the MB 11 Classic 4 4 Starting the software and menu 4 4 1 Menu File 4 4 2 Menu Settings 4 4 3 Menu About 4 5 Operation with mouse keyboard or touch screen 4 6 Registry of new patient data 4 7 Loading stored patient data 4 8 Working with a Today s list 5 Automatic testing in the AABR screening mode 5 1 Preparing the Patient tor measurements 5 2 Placement of the Electrodes 5 3 Placement of the eartips 5 3 1 Placement of eartips for infants 5 3 2 Placement of eartips for adults 5 4 Doing the screening test 5 4 1 Impedance Test 2 The signal quality control 3 Advanced display mode EEG Display 4 The function buttons 5 Test result Pass 6 Test result Refer 7 Test result Abort aural Screening 5 1 Preparing for a Binaural Screening 5 2 Binaural Screening Result A A A A A A UT UT es 5 oF ap J 5
2. 30 Test Time js M MAICO Ready 09 01 2008 Figure 28 MB 11 Binaural screening program Test result REFER MB11_Classic_E_12a_2 1 1 doc 32 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 6 Tracking The MB 11 Classic has been designed for Newborn Hearing Screening NHS Vital to the success of NHS Programs is an effective tracking and follow up protocol of the tested patients The new MB 11 software has an export function which allows export of relevant data into different database programs and into HI TRACK a database designed specitically to support Early Hearing Detection and Intervention programs All patient data from the start screen or the Today s list and the measurement results will be stored automatically in the tracking export Tile If you are working with tracking software this software will recall your tracking data The Tile will be renamed to make sure that the data will not be sent twice For further information contact the producer of your tracking software or your tracking center 6 1 Tracking Settings Choose Settings Sub menu MB11 M ller Norma Born 02 26 2008 Ag File Eee About Tracking System option Le Default Mode gt HIXTRACK Figure 29 Then click Settings Tracking System Settings MECS co L and the input window Figure 30 will open EC v HI TRACK Define the settings of the database directory Settings x Put in t
3. 5 2 Placement of the Electrodes For electrode placement the skin should be cleaned with cotton pad dipped in alcohol or acetone to remove any oil and dirt from skin Surface to minimize any potential skin impedance Using the finger rub the skin lightly until it turns slightly red this will help to reduce skin impedance and ensure accurate BERA result If the patient has very rough or dry skin rubbing the mastoid area with cotton pad soaked in salted water will helo to improve the BERA result MA Operating Instructions MB 11 Classic PATES Le Ground GND CA Mastoid a 4 Figure 15 Placement of the Electrodes After skin preparation apply one disposable electrode sticking pad on each of the three electrode placement points the vertex the ground and the mastoid An optimal BERA measurement can be achieved by having good electrode skin contact and accurate positioning of the electrodes 5 3 Placement of the eartips As human grow so do the ears and the ear canals Hence it is important to choose the right ear tip according to the patient s age and the size of the ear canal 5 3 1 Placement of eartips for infants As the ear canals for newborn infants are very small it is important to choose suitable ear tips especially designed tor babies Figure 16 Before inserting the ear tips connect them to the insert phone and rub the soft rubber tip between the thumb and the index finger to warm it up slightly be
4. Integrated 87 dB Amplification 23 000x Quality control Integrated indicator red signal quality low green signal quality OK Weight 300g Instrument MB 11 Box Power Supply via USB port of computer Power max 400 mA Consumption Weight 165g Dimensions WxDxH 12x9x3cm MB11_Classic_E_12a_2 1 1 doc 48 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic Computer requirements computer not included Type Intel Dual Core Atom 1 5 GHz RAM Minimum 1 GB RAM 2 GB RAM with Windows 7 Hard disk Minimal 5 GB free diskspace Interface USB 1 1 or 2 Display 1024 x 768 Operating system Windows XP Professional min SP 3 Windows 7 Professional 32 64 Bit or Ultimate 32 64 Bit NET Framework 3 5 SP 1 Mains supply Use only protective earth conductor plugs and wiring for the power supply The lack of grounding will lead to enhanced humming noise with a large affect on the measurement quality The buzzing noise also affects the audio output of computers and produces a masking noise signal This will falsity the results of the measurements PC battery Mode To assure the most undisturbed humming noise free measurement and masking noise free stimuli it is necessary to disconnect all external accessory PC devices such as those with external power supply like USB Units printers and local area network cables LAN If it is necessary to use accessory devices while you operate
5. Is a good practice to always check and make sure the instrument is clean and the tubing are free of clogging from dirt or oil Make sure that the cables are not broken or tangled or oppressed in any manner as this may destroy the wire embedded within To clean the MB 11 and other accessories use a damp soft cloth with some warm soapy water or detergent Please ensure that no liquid run into the instrument MB11 Classic E_12a 2 1 1 doc 45 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 11 Trouble shooting If you should find that your instrument is no longer working properly during a test run please check the following points 1 Instrument does not turn on Solution Are all cords and the plugged in correctly and the USB plug well fitted in the jack Please check the USB specification 2 The measurement Is running properly but with large regular EEG fluctuations Solution Can an improvement be effected via slightly moving the electrodes 3 No potential or only unclear potential is registered Solution Listen briefly to the earphone and verify that the click stimulation is present Ensure that the EEG was not interrupted by polarization of the electrodes which is easy to identify by extremely smooth curves shown in the EEG section and without any reaction to gentle movements of the MB 11 on the baby s head A simple test is to place the electrodes of the MB 11 on the inner side
6. No person should attempt to use this instrument without the necessary knowledge and training to understand how this equipment is to be properly utilized and interpreted MAICO Operating Instructions MB 11 Classic Specifications are subject to change MAICO MB11_ Classic E 12a 2 1 1 doc MAICO Diagnostic GmbH Salzuter 13 14 10587 Berlin Telephone 49 30 70 71 46 50 Telefax 49 30 70 71 46 99 e mail export maico biz Internet www maico biz 62 851 882 2 01 12
7. State Algorithm For Universal Newborn Hearing Screening UNHS current test methods include Otoacustic Emissions OAE and Auditory Brainstem Response ABR With OAE the preparation and the test time are fast But a significant handicap of OAE is a rather insufficient sensitivity and specificity With ABR hearing screening the sensitivity and specificity are very high but testing traditionally takes significantly more time than OAE screening With the patented ASS ABR algorithm which is implemented in the MB11 it is now possible to achieve test times that are comparable to OAE s The acoustical CE Chirp stimuli are applied with a high repetition rate 93 clicks second At this click rate a so called Auditory Steady State Response ASSR occurs The objective statistical recognition of the ASSR is done after the transformation of this strict periodic time function in the frequency domain The ASSR is described in the frequency domain by a few spectral lines harmonics the position in the spectrum is determined by the stimulus repetition rate and therefore well known The statistical test uses the phase and amplitude information of the harmonics below 800 Hz The spectral lines between the harmonics of the ASSR contain no signal but only noise or harmonics of the electrical interference These spectral lines will not be considered in the test result Beside the short test time another benefit of this method is the high immunity agai
8. arb units 0 5 10 15 20 25 30 Time ms Figure 49 CE Chirp Extensive investigations on newborns have shown that the CE Chirp Stimulus generates significant better results than other acoustical stimuli used for newborn hearing screening At 35 dBnHL stimulus level usually used for AABR newborn hearing screening we found a high specificity and short test time in newborns The combination of the CE Chirp and the Standard leads to very short examination times for newborn hearing screening MB11 Classic E_12a 2 1 1 doc 55 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 13 2 Sensitivity and specificity of the Auditory Steady State algorithm For a successful universal newborn hearing screening UNHS program it is essential to have a high rate of detection of severe hearing losses and a low referral rate of babies with normal hearing For better understanding the terms Sensitivity and Specificity are explained below in general and also specifically related to the ASS algorithm which is implemented in the MB 11 Sensitivity Percentage of positive results Refer Fail for newborns with severe hearing disorder Specificity Percentage of negative results Pass for normal hearing newborns The ASS regarding specificity Clinical investigations of newborns in a hearing screening program do normally not produce data from which an unbiased estimate of the specificity can be calculate
9. impulse to a transducer This click generates a traveling wave along the basilar membrane The traveling wave runs from the basal part of the cochlea along the basilar membrane to the tip of the cochlea apex Hereby it excites each of the frequency areas of the cochlea starting with high frequency part and ending with the low frequency part The velocity of the traveling wave is the greatest at the basal part of the cochlea and Slows exponentially towards the apex 10000 7920 1000 Frequency Hz Time ms Figure 47 Figure 47 shows the delay of the travelling wave for reaching the various frequency bands in the cochlea calculated trom the cochlea model of de Boer The figure shows a delay shorter than 2 ms for the region from 10 kHz to 1 kHz but a delay of 8 ms from the area of 1 kHz to 100 Hz Due to the resulting greater synchronization of excitation in the basal part of the cochlea only the higher frequency range contributes effectively to the click evoked activity The travelling wave delay in the more apical part of MB11_ Classic E 12a 2 1 1 doc 52 851 882 2 01 12 M Operating Instructions MB 11 Classic MAICO the cochlea is responsible for considerably dispersed responses from this area For this reason the spatio temporally summated response does not achieve the amplitude that would result from a more synchronous excitation The new CEC Stimulus implemented in the MB 11 Classic allows a well synchron
10. instrument during the measurement press CTRL U and the pop up window opens To close the program just click on the QUIT lt Q gt button located on the bottom right of the screen Additional functions are located in the Menu yi the top of the screen It contains the menus File Settings and About MB11_Classic_E_12a_2 1 1 doc 13 851 882 2 01 12 M MAICO 4 4 1 Menu File New Entry of a new patient see also Tracking Patient data Search Launches a dialogue field that allows selection of a patient out of the integrated database In this field a patient can be chosen by clicking the patient s name with the mouse or by typing the name The corresponding patient data appears in the fields of the start screen Print The window Print Measurement opens Choose the measurement you want to print out Print Mode This allows the type of printout to be selected choose selected Data printout to print a list of chosen measurement results Choose screenshot printout to print the graphical display on the complete measurement Printer Settings The settings of the printer can be individually set with the Printer Settings menu Quit Exits the MB 11 program MB11 Classic E_12a 2 1 1 doc 14 Operating Instructions MB 11 Classic I MB11 unnamed SEM Settings About New Search Print Print Mode gt Pr
11. intensity increases in 10 dB increments for each click in the packet Figures 36 and 37 As the entire click packet is presented in only 25 ms the patient is not aware of the complex composition but it is still processed with a high level of time precision in the brainstem If the six sound pressure levels of the click chain are arranged in such a way that the hearing threshold lies within this sound pressure range then a single averaging suffices to objectively determine the hearing threshold as those clicks below this level of course do not evoke any potential Standard ABR Lu lt Threshold is eee eee mm es ee ee cm e CON cour I7 X TOE E en Zs ia Chick Shirmulbus Click Stimulus Click Shmulus Soa l 2 1000 step Stimulus ABR alle en HP mai Fuser Sri muit 2 _ 1000 Figure 36 Stimuli Presentation with Standard ABR and Time Step Stimulus ABR MB11_Classic_E_12a_2 1 1 doc 37 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO Threshold Detection with the Time Step Stimulus Signal Response on 20 30 40 50 60 dB click no response oe dB 20 dB 30 dB 50 DdB 60dB 60 dB D EEE Rae Mc SE E ms 0 5 10 15 20 25 30 35 40 Figure 37 Typical ABR Response with the Time Step Stimulus Signal The white bars show the frame within which wave V for each of the evoking clicks is expected Click intensities are located above the c
12. mode IMPORTANT NOTE These two diagnostic tests are only available for single ear testing and should only be used by an experienced expert This offers the possibility of an immediate diagnostic evaluation of hearing after a screening result of REFER has occurred Using the Standard these tests are done under the same test conditions as the screening test For this purpose you can choose between Standard ABR with adjustable intensity or the Time Step Stimulus method which tests six intensities simultaneously Unlike screening the electrode behind the Mastoid should be placed accordingly corresponding to the ear being tested i e right Mastoid for right ear and lett mastoid for left ear Under good test conditions it is possible for an advanced tester to perform these measurements with a calm or sleeping baby or patient If you are not able to get good test results you should keep the baby calm by possibly feeding or sedating It You could also consider testing the baby another time when the baby is sleeping MB11 Classic E 12a 2 1 1 doc 36 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 7 1 Testing with the Time Step Stimulus 7 1 1 The Time Step Stimulus In the Standard ABR test the evoked potential is measured for individual clicks of a defined sound intensity Instead of individual clicks the step stimulus uses packets of 6 clicks following each other very rapidly in which the
13. normal hearing newborns with a good ASS response the amplitude of the response harmonics are harmonics Spektrale Amplitude TTI significantly higher than the noise M NL components If a hearing loss is ACT present the harmonics would not Auditory Steady State Response in the frequency domain be present significantly higher than the noise components and so would just blend in with the noise floor The statistical test decision is based on a comparison of calculated test values from the measured data with a so called critical test value To perform this calculation the continuous recorded EEG is separated into epochs of one second Only epochs having passed the artefact criterion will be used for further analyzing Each accepted epoch is transtormed into the frequency domain by Fast Fourier Transformation FFT In the frequency domain the evoked response is described by a certain number of spectral harmonics as described above Each spectral component is characterized by a phase angel and amplitude of the corresponding sinusoidal wave These data can be displayed as vectors in a polar coordinate system see Figure 52A If no response to the stimulus is present the epoch contains only noise If this is the case the vector endpoints in the polar display show a random distribution see Figure 52 B A single spectral component B No response C Response present random disribution spectral lines of harm
14. 2 1 1 doc 17 851 882 2 01 12 Operating Instructions MB 11 Classic MB 11 Patient us Lu oo Born Last name Pat ID MAICO R L C advanced Em ue MB11 BERAphone sin 1234567 i m 02 26 2008 Figure 12 Load from database After clicking on the button Search all stored patients will be shown see Figure 12 Select a patient with the cursor buttons or the mouse and load the stored data by pressing the Enter button or double click with the mouse If a test result of this patient Efe Settings About already exists the button Show n mu Measurements on the right of EEE IE Cas the screen see Figure 13 ne Finn FR becomes active By clicking ON A E this button you can scroll _ me through these test results and load them M MAICO R L Di advanced Figure 13 MB 11 program with loaded patient data and active Show Measurement button MB11 Classic E 12a 2 1 1 doc 18 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 4 8 Working with a Today s list WW MB11 M ller Norma Born 02 26 2008 Age 0 day s BAIE LE Settings About Patient pret Born Last name First name mm dd yyyy Pat ID Screener R Ear L C advanced ine ni O o MB11 BERAphone s n 1234567 02 26 2008 Figure 14 MB 11 Today s list If several tests will be conducted in one day it may be easier to ent
15. ERAphone s n 1234567 02 26 2008 Figure 19 Start measurement Prepare the patient and as described in chapter 5 1 and place the electrodes as described in chapter 5 2 Select the ear to be tested The ear s selected Right Ear Left Ear Binaural are displayed on the measuring screen Start the test by clicking on Start Measurement button Before measurement is started an automatic impedance test is performed MB11_Classic_E_12a_2 1 1 doc 23 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 1 Impedance Test A 5 es MAICO Figure 20 Start measurement The impedance is the resistance between the measuring electrodes Vertex Mastoid and the ground electrode This impedance is influenced by the resistance of the electrodes and more important of the resistance of the skin The impedance should be in the range of 250 Ohm to 15 000 Ohm for each electrode per Mastoid Ground and Vertex Ground Impedance in this range will allow the best EEG quality The top of the test screen shows the impedance traffic light Figure 20 Here the tester can see easily the status of the impedance test for each of the three electrodes The green colour symbolizes good impedance yellow means not optimal and red signals bad impedance The impedance values measured for Vertex Ground and Mastoid Ground lines are shown in the status line in the lower left corner at the screen In case of re
16. Is not an indication that the Tull auditory system is normal Thus a passing result should not be allowed to override other indications that hearing is not normal A full audiological 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 audiological diagnostic testing MB11 Classic E_12a 2 1 1 doc 5 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 3 Description MB 11 tests hearing function by measuring the auditory evoked potentials of the auditory pathway It records the appropriately filtered EEG in certain electrode configurations on the skull Repeated stimulation and averaging the corresponding EEG sections allows the signal noise ratio to be improved The spontaneous non stimulation related fluctuations in the EEG are reduced to a level that makes it possible to detect the element of the EEG evoked by the acoustical stimulation This permits objective audiometry the hearing threshold can be identified without participation from the patient babies infants 3 1 Auditory Brainstem Response ABR audiometry Brainstem potentials BERA brainstem evoked response audiometry or ABR auditory brainstem response do not require the patient to be awake ABR measurements can also be taken while the patient is asleep or under anaesthetics whereas
17. N 1 2 3 4 3 6 7 amp 8 10 30 80 70 90 Figure 2 Threshold detection from 90 to 10 dB HL with Latency Level diagram standard MB11 Classic E 12a 2 1 1 doc 8 851 882 2 01 12 MAICO 3 2 The MB 11 Classic EEG for brainstem audiometry was obtained by sticking electrodes to different points of the head of the patient The electrodes detect and record brainstem response evoked by acoustical signal delivered via the MB 11 Classic insert phone as shown in Figure 3 The MB 11 Classic with its flexibility can be used on any patient The MB 11 Classic can be used very advantageously with the patented fast reliable built in automatic ABR Auditory Steady State ASS test and the new CE Chirp Fast test time simple to use a high sensitivity of gt 99 9 anda high immunity against electrical interference and hum are the most important benefits of this algorithm The AABR test is described in details in chapter 6 1 and further diagnostic test like ABR and Time Step Stimulus are described in Chapter 7 MB11_ Classic E 12a 2 1 1 doc 9 MA Operating Instructions MB 11 Classic Figure 3 Testing with MB 11 Classic Stimulus le vel 35 dBHL M Fi wali ns DO UE EN a n m m a w w Pass 0 Q Figure 4 MB 11 PASS test result 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 3 3 Automatic Screening with the Auditory Steady
18. VE 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 All accessories are already packed in the compartment connected with the MB 11 Classic Please check that all accessories listed below are received In good condition If any accessories are missing or damaged immediately notity your dealer or MAICO Standard accessories MB 11 Classic 1 MB 11 Classic with amplifier with jacks for three electrodes and two sound transmitters set of Vertex Ground and Mastoid electrode cables set Left and Right Insert Phones packet of 25 single use adhesive electrodes additional disposable ear tips of different sizes USB connection cable Carrying bag CD Installation Software User Manual D MB11 Classic E_12a 2 1 1 doc 11 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 4 2 Preparing the MB 11 for use The MB 11 unit is supplied in a grey box connected with the MB 11 Classic through a cable A USB cable connects the MB 11 with a USB port of a Notebook or desktop computer CY I N Ss Figure 5 Classic with electrodes and MB 11 box The MB 11 s power is directly supplied through the computer via the USB port No external power supply is needed This makes the MB 11 Classic easy and safe to use 4 3 Getting familiar with the MB 11 Classic The MB 11 Classic should
19. atient ue Due Bom Last name First name mm dd yyyy Pat ID Screener Tracking Screening Time Step Stimulus Standard ABR 70 EH 65 60 1 TESS i E aivanced Print Measure Quit MAII MPH Arhere cin 125A TUTE Figure 38 Program start screen with Time Step Stimulus After clicking on the button Time Step Stimulus the start screen shown in Figure 38 is displayed You can select the maximum intensity of the time step stimulus test signal with the Level slider between 50 dBnHL and 70 dBnHL The default value is 60 dBnHL If the baby reacts sensitively to loud signals you should select 50 dBnHL gt AE ys au a Fie Settings About R Accepted ras Artifacts ce Artifact limit z 20 HV Amplitude 0 4 s 12 16 2 24 28 x 3 40 0 5 HV x Time ms 10d8HL WEH 304BHL sibh SOdSHL SOBEL 25 3 40 Stimulus Level 60 dBHL Right Ear Click Time Step Stimulus a Time fms Other Ear Start Measurement Quit 0272712008 Figure 39 MB 11 TSS Test Screen with Measurement After entering or loading the patient data select the ear to be tested Click on the Measure button and the test screen as shown in Figure 39 appears The EEG scaled in uV is displayed at the top of the screen If the EEG level is within the selected Artifact limit see box at the top left of the screen a measurement is performed and the number in the box Accepted increases by one MB11 Cla
20. be operated in a quiet room so that the examinations are not influenced by outside acoustic noises Electro medical instruments with strong electromagnetic fields e g microwaves radiotherapy devices can influence the function of the MB 11 Classic Therefore the use of these instruments is not allowed in close proximity to the MB 11 Classic The test room must be at normal temperature usually 15 C 59 F to 35 C 95 F If the device has been cooled down e g during transport please wait until it has warmed up to room temperature MB11_Classic_E_12a_2 1 1 doc 12 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 4 4 Starting the software and menu The Operating System of the Notebook or PC should first be started After successtul booting launch the MB11 Classic software by clicking the icon MB 11 USB Version at the desktop or direct from the program menu The program launches with the start screen see Figure 6 LS kaj MB 11 Patient born Last name First name mm dd yyyy 01 22 2008 O male Pat ID Examiner female L advanced Quit 01 22 2008 Figure 6 Start screen of the MB 11 program Device recognition You can connect up to 3 MB 11 Classic Beraphone devices pop up window displays the connected instruments If more than one MB 11 is connected you can choose the device you want to work with by mouse click To change the
21. d Therefore the precise value of the Specificity cannot be given Besides Hearing Loss restless babies during the test or electrical distorting fields in the test facility can lower the Specificity Regarding sensitivity To assess the sensitivity usually a signiticantly high number of babies with known hearing loss must be tested Sensitivity estimate of the ASS Due to the high stimulus repetition rate of 93 Hz a periodic signal ASS response will be generated trom the auditory system see Figure 34 The averaging result in the time domain shows a clearly visible wave between 8 and 10ms with a broader part between 2 and 6ms The ASS detection algorithm operates in the frequency domain Atter transtormation l of the Example of one a Ad Steady State measured response INtO the response in the time domain stimulus repetition rate frequency domain the periodical 93 Hz response is represented by a relatively low number of harmonics see Figure 51 All harmonics below 800 Hz are considered by the test statistic at a click rate of 93 s 8 harmonics are included Between the harmonics a large ha gt E Q D a i MB11_ Classic E 12a 2 1 1 doc 56 851 882 2 01 12 M Operating Instructions MB 11 Classic MAICO number of spectral components at a resolution of 1 Hz approx 90 ST spectral components are located which contain no information about the response only noise In
22. d V I V is as a particular characteristic of the ear independent of the click stimulus intensity see Figure 2 A value exceeding 4 5 ms for I V is generally regarded as pathological indicating need for follow up examinations The largest potentials are obtained when the electrodes are positioned in the direction of the propagation of the excitation in the auditory pathway wave V in line with Its origin in the ascending section of lateral lemniscus is measured best with a vertical electrode placement Accordingly an ipsilateral mastoid versus vertex or hairline on the forehead is chosen for electrode placement The mastoid ipsilateral to stimulation side supplies wave for this ear For detection of wave Ill to VI the contralateral mastoid is just as suitable for electrode positioning MB11 Classic E_12a 2 1 1 doc 7 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO The short click stimulus 100 us excites auditory nerve fibres in the region of 1 to 3 kHz ABR responses are therefore not frequency specific Letenz tes I II Tit Tv a vi vit yy I v 0 e a t 6 3 9 6 7 2 A 4 00 ES y A 1 6 4 0 56 g a 2 32 4 00 8 3 002 A 2 0 4 2 8 9 2 20 2 2 6 4 50 A 2 2 4 8 6 2 7 7 2 40 4 00 t BS Sod A 2 4 4 6 S 2 0 2 26 4 00 8 6 22 A 2 6 5 3 g 5 5 2 44 2 amp 8 7 A 2 2 5 7 2 9 3 8 2 40 4 00 7 3 20c8 A 6 2 7 2 amp B 028 A 5 0 a aes SER ee eee ee ee ee eee eee ee ee eee eee ee eee C
23. d light the impedance needs to be corrected Please repeat the preparation with the electrode gel for lowering the impedance of the skin In some cases it takes some time until the electrode gel takes into effect The impedance test is passed when for seven seconds all three electrodes show green or yellow After passing the impedance test the measurement starts automatically and the impedance traffic light changes into the signal quality traffic light MB11_Classic_E_12a_2 1 1 doc 24 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 2 The signal quality control Signal Quality UE Site Abe Signal Quality cru EE EEE EEE HHHH HHHH one S waed 2 m siared C advan Stimulus Level 35 dBHL Quit B a w x AA Stimulus Level 35 dBHL ee poe AA Test in progress r MAICO 7 S ment i Quit Figure 21 MB 11 program test screen showing bad and good signal quality The signal quality in the screening mode is determined by the ratio of artifact and accepted signals Artifacts are big potentials caused by electrical noise muscle activity or muscle tension The quality is low if at a time scale of 1 second the amplitude of the response is at 300 time points bigger than the artefact level it is possible to change the artifact level in the advanced mode indicating a high electrical noise level or muscle activity of the patient Signal quality depends strongly on the correct pos
24. e The MB 11 Classic software allows the export of data from the database for detailed analyzing The export file will be exported as text Tile txt in the Excel compatible CSV format The CSV format allows easy import into Excel or other software To exp O rt d ata cl C k Load from Database Search on the start screen doyle 12721 2005 gt e D qT h g LO a d D q ta D a SE g 5 testgeburtstag Fa dialogue appears Choose the s En 11 11 i briede 08 23 2006 d d ta fo r exp O rt d n d C C k Exp O rt briede2 eer re La Type in the name of the export file and the location for storage Click rette ok MB11_ Classic E 12a 2 1 1 doc fall data LA Export Cancel Figure 34 Load from Database 35 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 7 Follow up measurements Not available for the MB 11 Classic Screener Diagnostic test for the follow up after a REFER result can be enabled by clicking on the box advanced on the lower right of the start screen The start screen now displays two additional tests Time Step Stimulus and Standard ABR MBIN unnamed EE MB 11 Patient i E E born Last name First name mm dd yyyy 01 22 2008 3 O male Pat ID Examiner Tracking data O female R Ear L advanced MB 11 BERAphone s n 1234567 l 01 22 2006 Figure 35 MB 11 program start screen in advanced
25. e Step Stimulus MAICO Other Ear Start Measurement Quit TRES TNT TT MB 11 program result Time Step Stimulus MB11_Classic_E_12a_2 1 1 doc AO 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 7 1 3 Advanced display Time Step Stimulus Test The advanced display mode can be entered by clicking on the box advanced on the left side of the test screen This test screen contains o additional information and features This 2 PANA mode is available for the current test result as well as for the stored data De S E Ea Figure 41 and 42 display the test result lk shown in chapter 7 1 2 Figure 41 in Figure 41 the advanced display format Test screen advanced During the test the single measurement sweeps are stored alternatively in the A 7 and B Buftter It is possible to display data within the A and B Bufters a oi by run aol SE NENA AUS unction located at the left of the test ee RR screen When this is selected the V WN i averaged data will be displayed at the gy zt Tree bottom and the data stored within the separate A and B Buffers will be D a displayed at the top The Filter function allows you to smooth the curves on the screen The cut off frequencies of the filter are 163 Hz and 1930 Hz The boxes for the adjustment of the artifact limit and the amplitude of the AEP display are located on the upper left part
26. ensitivity can be determined To ensure a high sensitivity the implemented algorithm works with a critical test value which realizes the very low error probability a 0 004 see Figure 53 modified q sample uniform scores Test frequency test value Figure 53 Estimated probability density MB11_Classic_E_12a_2 1 1 doc 58 851 882 2 01 12 M Operating Instructions MB 11 Classic MAICO In general with a statistical test the reduction of the error of the first kind increases the error of the second kind the increase of the sensitivity creates a decrease of the specificity because the probability density functions of the null hypothesis and the alternative hypothesis overlap more or less But with the ASS algorithm this overlap is very low The test power is very high because even with the extremely low probability of error the sensitivity for precise response detection is very high With the given exact critical test value a sensitivity of nearly 100 99 99 is maintained A detailed description of the used statistical tests is published by Sturzebecher et al 2003 A procedure to determine the critical test value with using a sequential test procedure is described in St rzebecher et al 2005 Click evoked ABR at high stimulus repetition rates for neonatal hearing screening Sturzebecher E Cebulla M and Neumann K Int J Audiol 42 2 59 70 2003 Automated auditory response detection statis
27. er is committed to dispose of the delivered goods according to the rules stipulated by law The costs for disposal have to be paid by the end user MB11_Classic_E_12a_2 1 1 doc 60 851 882 2 01 12 M MAICO Operating instructions MB 11 Classic 15 Safety Regulations MB11 Classic E 12a 2 1 1 doc 61 851 882 2 01 12 15 1 Electrical Safety The MB 11 Classic ABR Screener is specified to comply with the international standard IEC 601 1 EN 60601 1 The MAICO MB 11 is guaranteed according to IEC 601 1 safety against electrical hazard only when the connected notebook computer is powered by batteries or the computers power supply accords to IEC 601 1 or IEC 950 1 safety regulations The instruments are not intended for operation in areas with an explosion hazard 15 2 Measuring security 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 we will drop our liability if these checks are not done 15 3 Device control 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 15 4 User Instruction The MAICO MB 11 Classic is designed to be used only by skilled personnel Audiologists physicians or other trained personnel
28. er the data of all babies before you start to test In this case click on the button New data and enter the name birth data and sex as described in chapter 4 6 After the data is entered click on the button Add to Today s list Now click again on the button New data and proceed as described before Repeat this until you have entered the data of all babies to be tested Later on when testing you just have to click the button Display Today s list The list of the babies to be tested today appears on the screen After selecting the baby to be tested select the ear to be tested right R or left L and start the test by clicking on the button Measure For the test procedure refer to chapter 5 The today s list will be erased automatically at midnight of the next day to avoid misunderstandings Of course the stored test results remain in the database MB11_Classic_E_12a_2 1 1 doc 19 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 5 Automatic testing in the AABR screening mode It is easy and fast to screen with the built in patented automatic Auditory Steady State Algorithm Screening means that during the test it will just be determined if the newborn patient has the possibility of a significant hearing loss and needs further evaluation PASS As soon as the indication mark reaches the green area 100 Pass criteria the result is PASS REFER If no response at the test level o
29. ered by batteries or the computers power supply accords to IEC 601 1 or IEC 950 1 safety regulations Precautions READ THE ENTIRE MANUAL BEFORE ATTEMPTING TO USE THIS UNIT Use this device only as described in this manual AN Before measurement make sure that the device works properly Do not drop or cause undue impact to this device If the instrument is dropped or damaged return it to the manufacturer for repair and or calibration Do not use the instrument if any damage is suspected Do not immerse the unit in any fluids See the Cleaning section of this manual for proper cleaning procedures Use and store the instrument indoors only Do not expose this instrument or its accessories to temperatures below 59 F 15 C or above 95 F 35 C or to relative humidity of more than 75 Do not attempt to open or service the instrument Return the instrument to the manufacturer for all service Opening the instrument case will void the warranty MB11 Classic E_12a_2 1 1 doc 4 851 882 2 01 12 Operating Instructions MB 11 Classic A Disclaimer The MAICO MB 11 Classic 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 normal evoked potentials suggests normal hearing However a passing result using this instrument
30. f 35 dBnHL is found the test result is REFER In this case a Follow Up with diagnostic measurements Should be done by a specialist see chapter 7 ABBORT If the test is aborted a pop up window with reasons appears l e Test aborted because Technical Problems Invalid The reason will be stored in the database for quality controlled tracking Because no judgements or interpretations of the screening results are necessary the test can be easily done by properly trained personnel Additional information and results are available at any time for the doctor or specialist see chapter 5 4 5 1 Preparing the Patient for measurements Before any measurement the patient should be informed of the test procedure Electrodes will be fixed onto three different points of the patient s head i e the top of the forehead vertex the temple and the mastoid The test will cause neither harm nor discomfort The patient should be seated in a relaxed and comfortable position to minimize any potential muscular artefact and ensure optimum test outcome in the shortest time A comfortable reclining armchair that supports the head neck shoulders and arms is most suitable Make sure that the face neck and shoulder of the patient are relaxed and free of any obstructions Proper EEG measurements require a low skin electrode resistance electrode impedance MB11_Classic_E_12a_2 1 1 doc 20 851 882 2 01 12 MAICO
31. fore putting them into the ears of the babies This will help to avoid discomfort and thus facilitates the screening Figure 16 Process MB11 Classic E 12a 2 1 1 doc Moulding of the earphones 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 5 3 2 Placement of eartips for adults Before inserting the eartips the soft and pliable noise excluding form surrounding the sound tube should be shaped and moulded by pressing using the fingers to fit the size of the outer ear canal of the patient Figure 17 Ensure that the form does not obstruct the sound tube in any way It is recommended to connect the earphone to the respective insert phone of the MB 11 Classic before inserting the foam eartips into the patient s ears to avoid any discomfort If the patient is laying down place the left and right insert phones next to the patient If the Figure 17 patient is sitting clio both the left and right Moulding of the earphones insert phones onto the patient s clothes or any pockets if available to avoid pulling of the sound tube As this may distort the sound quality delivered When the eartip is in place the flexible noise excluding form will slowly expand to fit the ear canal and thus exercising its noise excluding property When in doubt ask the patient if external sound appeared muffled If the patient answers Yes then the eartips are properly placed ATTENTION After the test all
32. h non physiological high stimulus levels Due to this fact the cochlea delay derived from the de Boer model has to be considered as not optimal For this reason a new model function of the frequency dependent propagation time in the cochlea was calculated based on the latency data of frequency specitic ABR recorded at low stimulus levels MB11 Classic E_12a 2 1 1 doc 54 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic In this context the question arises as to whether the delay of the different models has to be considered to reflect the group delay or the phase delay of the cochlea The phase delay describes how much a steady state cosine of a specific frequency is delayed from the input to the output of a system of the cochlea The group delay describes how much the envelope of a signal formed by a narrow group of frequencies is delayed through the system The results of a study confirmed the assumption that the latencies of the frequency specitic ABR reflect the group delay Since the stimulus shall compensate for the cochlear delay of single frequencies the phase delay calculated from the group delay was used for the phase correction of the individual cosines of the stimulus Figure 48 c shows the time course of the resulting CE Chirp Stimulus For preventing an overlapping of response harmonics by electrical artefacts the above described frequency offset has to be added too 0 5 0 0 Rel Amplitude
33. he name of the clinic screening location and physician Menu setting HI TRACK The examiner id will be assigned automatically The patient id can be generated by the system automatic pat id The system can also check the patient id by check sum check pat id Figure 30 Input window Tracking settings MB11_Classic_E_12a_2 1 1 doc 33 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 6 2 Input of Tracking data If Settings HIGH TRACK is activated the function button Tracking appears on the start screen YI MB11 Maico Mike Born 06 09 2004 Age 4 year s File Settings About MB 11 Patient T Oom ay New Search Add to Today s List Display Today s List Show Measurements Last name First name i wa WIKI Pat ID Screener cron INC f pe Born mm dd yyyy ig a Teras aly O female Time Step Stimulus M MAICO R Ear tare oe L Standard ABR advanced MB 11 BERAphone s n 8877070 Figure 31 09 01 2008 Start screen with function button Tracking Click on Tracking to open the input window Figure 32 Patient data will be copied from the start screen All out the form Activate the check box Parents permission Tor screening Depending on your tracking system even more data may be required Click on the advanced button to open the next Input windo
34. in the battery mode ensure a separate continuous and sufficient grounding of your PC MB11_Classic_E_12a_2 1 1 doc 49 851 882 2 01 12 M MAICO Operating instructions MB 11 Classic Standard accessories 1 d A MB11 Classic E 12a 2 1 1 doc 50 851 882 2 01 12 MB 11 Classic with amplifier with jacks for three electrodes and two sound transmitters set of Vertex Ground and Mastoid electrode cables set Left and Right Insert Phones packet of 25 single use adhesive electrodes additional disposable ear tips of different sizes USB connection cable Carrying bag CD Installation Software User Manual MA Operating Instructions MB 11 Classic MAICO Connecting plugs Connection Specification USB socket USB USB 1 1 max 400 mA ue Ni f Figure 46 Connector of MB 11 MB11 Classic E 12a 2 1 1 doc 51 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 13 Scientific Background Information 13 1 CE Chirp Stimulus The stimulus for an AABR newborn hearing screening should generate auditory evoked brainstem responses with an amplitude as great as possible at the level of 35 dB HL High response amplitudes allow a fast objective detection with high specificity and short measuring time Up to now in the field of hearing screening the standard click was used as stimulus The standard click is generated by delivering a short rectangular electrical
35. inter settings Quit Figure 7 File Menu J MB11 Maico Melanie Born 01 14 200 SEM Settings About New Search Print Print Mode a y Selected Data Printout Printer settings Screenshot Printout Quit Figure 8 Print Mode 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 4 4 2 Menu Settings Language The program language can be changed i e to English German French Chinese or Japanese Default Mode Options Screening only and advanced The advanced mode offers additional diagnostic tests Time Step Stimulus and Standard ABR Tracking System For a brief screening test choose no tracking HI TRACK The MB 11 software is full HI TRACK compatible and supports secured quality tracking Tracking Settings Define the export directory for the tracking data and insert clinic data Default setting for Examiner Screener is the user of the computer login identification 4 4 3 Menu About iw MB11 unnamed Encens About Language t Default Mode b Tracking System b Figure 9 Settings Menu Figure 10 Tracking Settings Clicking on About to see product information about the software version and contact information MB11 Classic E 12a 2 1 1 doc 15 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 4 5 Operation with mouse keyboard or to
36. ition of the electrodes and on electrical noise in the surrounding environment Also potentials from muscle activity disturo the measurements The signal quality traffic light is located at the top of the test screen Red indicates low yellow indicates fair and green indicates good signal quality As soon as the signal quality turns yellow or green the test starts The signal quality indicator light on the MB 11 Classic also shows whether the signal quality is good or not As long as the signal quality on the screen is red the signal quality indicator lights red too As soon as the signal quality is better and the test starts the signal quality indicator on the MB 11 Classic changes to green If the signal quality decreases for a certain time the signal quality indicator on the MB 11 Classic changes to red again and the test is paused Try to increase the signal quality again by moving the MB 11 Classic slightly to improve the impedance If the bad signal quality is caused by movements from the baby and muscle artifact the test will continue automatically as soon as the baby is calm and the signal quality is good again IMPORTANT It is recommended to advise patient to close his her eyes during the test and not to wink frown laugh swallow or make any facial movement as this will result in muscle potential that subsequently impedes the signal quality MB11_Classic_E_12a_2 1 1 doc 25 851 882 2 01 12 MA Operating Instructi
37. ized activation of the whole cochlea In contrast to the conventional generation of a click in the time domain in the frequency domain a click like stimulus can be created through the addition of a large number of cosines with a fixed frequency difference The frequency difference is selected in accordance with the desired stimulus repetition rate a Amplitude o Spectral amphtude dB 5 0 5 10 15 20 25 30 35 40 0 250 500 750 1000 7250 7500 7750 6000 Time ms Frequenz Hz oa E Ampbtude Spectral amplitude dB gt 1 0 5 tG 15 20 25 30 35 21 0 250 500 750 1000 7250 7500 7750 6202 t Oo Ce Time ms Frequenz Hz c Amplitude Spectral ampliude dB 20 25 30 35 C 0 250 500 750 1000 7250 7500 7750 8000 Time ms Frequenz Hz O Figure 48 Figure 48 a shows in the right panel the frequency spectrum of such a click Every component of the spectrum represents a cosine The difference between the single cosines is 90 Hz and is equal to the stimulation rate of 90 s A ripple between the individual pulses of the stimulus in the time domain shown in the left panel of Figure 48 a can be effectively reduced by halving the amplitudes of the cosines with the lowest and the highest MB11 Classic E 12a 2 1 1 doc 53 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic frequency In contrast to the standard click generated in the time domain the new stimulus is a steady state signal The
38. ndatory When you leave the test screen by clicking on the button QUIT the test result will be stored automatically in the data base MB11_Classic_E_12a_2 1 1 doc 29 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 7 Test result Abort m 75 m D _ advanced 2 25 Stimulus Level 35 dBHL AA 0 10 20 30 40 So 60 70 80 90 100 110 120 130 140 150 160 170 180 Test Time js Abort Invalid E ia Da RS a DANONE h_e e WAO Other Ear Start Measurement Quit MB11 BERAphone sin 1234567 r 02 27 2008 Figure 26 Test result Abort If the test is aborted a pop up window with reasons appears After confirming a reason the result Abort with reason is shown in the green area see Figure 26 When you leave the test screen by clicking on the button QUIT the test result will be stored automatically in the data base MB11_Classic_E_12a_2 1 1 doc 30 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 5 5 Binaural Screening With the MB 11 Classic a binaural testing is made possible This allows both ears to be screened at the same time with screening time generally under 20 seconds for both ears 5 5 1 Preparing for a Binaural Screening Preparing the patient as described in chapter 5 1 When the patient is ready click on Other Ear on the measuring screen until Binaural in pink lette
39. nst distortion from electrical hum and ripple The statistical test is done in samples of one second The first test is done after passing the impedance test and then the test is repeated every second until the overall test result arrives at critical value the green marked PASS criteria see Figure 5 Then the test will be stopped with the test result PASS If the PASS criteria is not achieved after 180 seconds the test is stopped with the test result REFER MB11_Classic_E_12a_2 1 1 doc 10 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 4 Getting started All Notebooks delivered by MAICO have the correct settings and the MB 11 software is already installed If you use not a Notebook delivered by MAICO please follow the instruction in chapter Installation and Settings or contact your local dealer 4 1 Unpacking your instrument Your MB 11 Classic was carefully inspected and packed for shipping However it is good practice to thoroughly inspect the outside of the shipping box for signs of damage Carefully remove the instrument from the shipping box Remove the plastic bag from the instrument and inspect the case for any damage If any damage is noted please notify the carrier immediately 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 SA
40. nt 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 normal hearing persist When you leave the test screen by clicking on the button QUIT the test result will be stored automatically in the data base MB11_Classic_E_12a_2 1 1 doc 28 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 6 Test result Refer O advanced N Stimulus Level 35 dBHL l A 2 j Refer MAICO Other Ear Start Measurement Quit ben Aphone sin 1229567 00 18 2008 Figure 25 MB 11 program Test result REFER If 100 of the pass criteria is not reached after three minutes test time the probability for a hearing loss is very high This needs to be assessed by a follow up diagnostic The small status window in the lower right of the screen shows the test result as Refer Figure 25 If you cannot exclude bad test conditions as a reason for the Refer you should retest If the test was done without any errors the newborn should be referred for a follow up audiological examination by experts If parents are watching the test they should be instructed that the test result is not a detection of an eventual hearing loss But to exclude the possibility of a hearing loss a follow up is ma
41. o Ear 1 L L advanced MB 11 BERAphone s n 8877070 n 09701 2008 Figure 11 MB 11 program start screen with patient data For a fast screening test without tracking it will be enough to register the name birthday gender and Patient ID Tracking may require more detailed data Read more in Chapter 6 Tracking Enter the surname and first name of the patient baby with the keyboard Move between the different entry fields using the lt tab gt key or a mouse click in the required data field The current date is displayed as the default value for the date of birth The arrows on the right of the date field can be operated with the mouse to increase or decrease the value alternatively use the A and Wcursor buttons of the keyboard or enter the date with the numeric keyboard Mark the sex of the patient by clicking the box male or female The lt Del gt key can be used to delete the default setting prior to entering a different value When Tracking System is activated it is possible to mark the patient as outpatient Additionally you can load stored patient data see chapter 4 7 or create a today s list of the patients to be tested today see chapter 4 8 Select the side of the ear to be tested lt R gt for right or lt L gt left using the Ear button or the R L slide just above the Measure button Now you are ready for testing The test procedure is described in chapter 5 MB11 Classic E_12a_
42. oF In 5 oF 6 Tracking 6 1 Tracking Settings 6 2 Input of Tracking data 6 3 Advanced Tracking data 6 4 The export functions of the MB 11 database 7 Follow up measurements MB11 Classic E 12a 2 1 1 doc 1 11 11 12 12 13 851 882 2 01 12 MAICO 7 1 Testing with the Time Step Stimulus 7 1 1 The Time Step Stimulus 7 1 2 Testing with the Time Step Stimulus 7 1 3 Advanced display Time Step Stimulus Test 7 2 Testing with Standard ABR 8 Recommended literature 9 Installation and Settings 9 1 USB Specitications 9 2 Installation of MB 11 Software 9 3 Computer Settings for optimal performance 10 Care and maintenance of the instrument 11 Trouble shooting 12 Technical Data 13 Scientific Background Information 13 1 CE Chirp Stimulus M Operating Instructions MB 11 Classic 37 37 39 41 42 43 44 44 44 44 45 46 47 52 52 13 2 Sensitivity and specificity of the Auditory Steady State algorithm 56 14 Warranty Maintenance and After Sales Service 15 Satety Regulations MB11_Classic_E_12a_2 1 1 doc 2 60 61 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 1 Introduction Thank you very much for purchasing a quality product from the MAICO family This automatic ABR test system MAICO MB 11 Classic 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 de
43. of your lett arm The skin of the arm should be prepared by cleaning The current variation is determined by the muscle potentials of the arm It is important to test that the muscle potentials of the arm are being recorded correctly that means contraction yields larger potentials relaxation smaller ones MB11_Classic_E_12a_2 1 1 doc 46 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 12 Technical Data CE The MB 11 Classic is an active diagnostic medical product according 0123 to the class lla of the EU medical directive 93 42 EEC Standards Test signals Stimulus rate EEG filter Sample rate Quality control Environmental conditions Probe Standard Speaker Electrodes Level range MB11 Classic E 12a 2 1 1 doc IEC 601 1 IEC 645 3 Screening CE Chirp Stimulus Time Step Stimulus Opt Click ABR Opt Click Screening 93 s 20 s Time Step Stimulus Standard ABR 14 s 125 Hz 1 25 kHz 16 kHz Integrated indicator in Standard and display in software with signal quality display or with EEG 15 35C 59 95 F operation 5 450C 41 122 F storage Maximum humidity 75 operation Maximum humidity 90 storage Integrated dynamic wideband speaker 8 Q Reusable stainless steel electrodes with gel protectors 0 to 70 dBnHL 4 7 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic Preamplifier
44. of the screen see Figure 43 The actual value of the artifact limit is shown under Artifact limit For example in Figure 36 the actual artifact artifact limit limit is 20 uV The artifact limit can be adjusted by clicking on 20 the arrow right of the Artifact limit box Values between 5 uV pare and 50 uV are selectable The display magnitude of the AEP s Tow D waves is shown under Amplitude For example in Figure 36 the actual amplitude is 1 1 uV Figure 43 The amplitude can be adjusted by clicking on the arrow right any eel of the Amplitude box Values between 0 1 uV and 1 1 uV are selectable Accepted 2400 Artifacts 10 s e tr aen MB11 Classic E_12a_2 1 1 doc 41 851 882 2 01 12 Operating Instructions MB 11 Classic MB 11 Patient Ds Lens Done De Bom Last name First name mm dd yyyy Pat ID Screener Tracking Screening Time Step Stimulus Standard ABR z MAICO R Ear L advanced as MB11 BERAphone ain 1234567 02 27 2008 Figure 44 MB 11 program start screen in expert mode Standard ABR After clicking Standard ABR on the start screen an intensity level selector appears as shown in Figure 44 The intensity level for the click can be adjusted between O and 70 dBnHL using the slider adjustment Next select the Ear to be tested by clicking R for right or L for left ear and then click Measure to begin the test The screen shown in Figu
45. onics grouped together Figure 52 Amplitude and phase angel of the sinusoidal waves corresponding to the spectral lines displayed in the polar coordinate system MB11 Classic E_12a 2 1 1 doc D 7 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic Calculate the critical test value The algorithm uses the phase angle and the amplitude of the first eight harmonics of the response to calculate the test value The statistical test Is carried out in the following way The first test value will be calculated with a sample of the first 15 epochs If the test value is less than the critical test value the sample will be increased by one epoch and tested again This procedure will be continued until the test value is equal to or greater than the critical test value Then the testing Is stopped with a Pass result If the critical test value is not reached after 120 epochs the test will stop with a refer result The critical test value used by the algorithm was calculated by a Monte Carlo simulation A very large amount of random data was generated The critical test value was then determined with the frequency distribution of the test values calculated for this data The frequency distribution of the test values is a good estimate of the probability density function of the null hypothesis HO no response present With the HO the critical test value for a given error of the Tirst kind error probability a 100 a s
46. ons MB 11 Classic MAICO 5 4 3 Advanced display mode EEG Display The advanced display mode can be entered by clicking on the box advanced on the left of the test screen Artefact limits can be selected from the pull down menu located to the left of the EEG display Choices include 40uV 50 uV and 60 LV WMLMB11 Maico Melanie Born 0 4 2008 Age 8 day s File Settings About 40 Artifact limit 40 uV v 20 Hau Sos er e Lt Pe ae ee TN D Do cer JS 20 EEG uv 4 5 10 15 25 30 35 40 20 Time ms Pass criteria a advanced Stimulus Level 35 dBHL AA 0 10 20 30 40 50 60 70 80 30 100 110 120 130 140 150 160 170 130 Test Time js IAA Test in access MAICO ther Stop Measurement pause LEGS Bi 01 22 2008 Figure 22 Test screen in advanced display mode MB11 Classic E 12a 2 1 1 doc 26 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 4 The function buttons Stimulus Level 35 dBHL 70 140 30 100 Test Time js Pass Other Ear Start Measurement US Quit MB 11 BERAphone sin 1234567 l 01 22 2008 Figure 23 MB 11 program Test stop At the bottom part of the test screen are the function buttons Other EAR To select the ear s for testing Left blue Right red or Binaural purple Start Measurement Clicking on the Start Measurement button starts a new test The function button changes to St
47. op Measurement Stop Measurement An ongoing test can be aborted by clicking on the button Stop Measurement The pop up window Test aborted because opens The result Abort and the reason will be displayed and stored in the database for quality controlled tracking Pause Stops the ongoing test In this case this button changes to Continue and the status indication at the bottom of the screen shows Test in progress Quit Finishes the measurement and returns to the start screen Advanced The advanced display mode shows the EEG Artetact limits can be selected from the pull down menu located to the left of the EEG display MB11_Classic_E_12a_2 1 1 doc 27 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 5 4 5 Test result Pass iW MB11 Maico Melanie Born 01 14 2006 Age 8 day s File Settings About _ advanced Stimulus Level 35 dBHL AA 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 Test Time js JV Pass MB 11 BERAphone sin 1234567 01 22 2008 Figure 24 MB 11 program Test result PASS During the test the indication line for pass criteria in the diagram continues to move upward on the graph until the green area is reached Then 100 of the pass criteria is fulfilled and the test was passed successfully The result PASS is shown in the green area see Figure 24 However a PASS result using this instrume
48. orresponding column white bar The step stimulus curves permit a direct reading of the ABR hearing threshold The white bars with the anticipated latency of the relevant wave V are very useful The center of these white bars Is set for the timing of the normal latency intensity function and is shifted according to the age of the patient as entered in the patient data Therefore The latencies of the wave V s for an individual must always be in the same temporal relationship to the bars It is not possible Tor wave V at 50 dB for example to be at the end of the 50 dB bar but for 40 dB at the beginning of the 40 dB bar From the highest intensity onwards waves must be traceable without a gap through to the threshold The amplitude of the highest intensity can turn out to be slightly smaller but must still be recognisable It is not possible for the 60 dB and 50 dB waves and also the 30 dB wave for example to be clearly recognizable but no response identifiable at 40 dB In this case the wave at 30 dB is determined to be artefact and not a reliable evoked potential If necessary repeat the measurement to clarify the situation A good indication Tor genuine ABR potentials is a peak one column width before the wave V This is the wave Ill but it is not always well formed MB11_Classic_E_12a_2 1 1 doc 38 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 7 1 2 Testing with the Time Step Stimulus MB il P
49. patented stimulus constructed from individual cosines offers the possibility of introducing a frequency dependent phase correction in order to compensate for the propagation time in the cochlea From this phase correction a synchronized activation of the whole basilar membrane can be expected Figure 48 b shows to the left the time course of a phase corrected click The corresponding amplitude spectrum is shown at the right side The red arrows mark the position of the first six spectral harmonics of the brainstem response evoked by the phase corrected stimulus These harmonics were analyzed by the objective statistical test Implemented in the automatic test algorithm of the MB 11 Classic software It is easy to see that five of the six harmonics of the brainstem responses are overlapping with the stimulus frequencies This overlapping could lead to false results of the statistical test when electrical stimulus artefacts occur For elimination of this source of error a frequency offset is Introduced into the cosines This frequency offset causes a displacement of the stimulus frequency spectrum In the time domain the frequency offset leads to an alternating stimulus With this stimulus a better detection time and shorter test time could be realized For further optimization the question of the adequate cochlea model for calculating the phase correction was addressed The cochlea model trom de Boer is based on measurements at ears of dead bodies wit
50. r is disolayed Click on Start Measurement to begin measurement 5 5 2 Binaural Screening Result Unlike monaural test the binaural measurement will display two coloured lines red for the right ears and blue for the left Both ears are screened for hearing loss at 35dBnHL If responses are detected from both ears the lines move upward until it reaches the 100 area coloured green then the result will be shown as PASS If no response is detected the lines do not reach the 100 green area after 180 seconds the result will be REFER NOTE For Binaural Testing a PASS result can only be obtained when the 100 pass criteria are reached by both ears Figure 27 If either of the ears fails to reach the 100 pass criteria after three minutes even if the other ear had reached the 100 pass criteria the screening result will be shown and recorded as REFER for proper follow up actions Figure 28 MB11_Classic_E_12a_2 1 1 doc 31 851 882 2 01 12 Operating Instructions MB 11 Classic MAICO File Settings About Pass criteria _ advanced Fe Stimulus Level 35 dBHL 10 20 30 40 50 100 110 30 Test Time js 09 01 2008 Figure 27 MB 11 Binaural screening program Test result PASS File Settings About l il fe aay 10095 Pass critetia J v _ advanced 25 D Stimulus Level 35 dBHL 19 20 30 40 50 60 70 100 110 120 130 140 150 160 170 180 80
51. re 45 will appear In contrast to the time step stimulus the Standard ABR will only test at a single intensity When sufficiently high Stimulus levels are used all waves V should be visible Other options and displays shown in this Standard ABR screen are explained in detail in chapter 7 1 2 of this manual Accepted 2400 Artifacts 10 Artifact limit 2 20 uV Dex Amplitude 6 10 0 5 LV 3 My v n d Tate 4 a g advanced Time fms a Stimulus Level 60 dBHL Right Ear Click Standard ABR Other Ear Start Measurement f Quit 02 27 2008 Figure 45 MB 11 program test screen Standard ABR MB11 Classic E 12a 2 1 1 doc 42 851 882 2 01 12 M MAICO 8 Recommended literature Audiometric Interpretation Auditory Disorders Handbook of Clinical Audiology s Audiology Desk Reference Auditory Diagnosis Rapid threshold estimation using the chained stimuli technique for auditory brain stem response measurement 1991 Automated auditory response detection statistical problems with repeated testing Objective Detection of Auditory Steady State Responses Comparison of One Sample and q Sample Tests New efficient Stimuli tor Evoking Frequency Specitic Auditory Steady State Responses New Click like Stimuli for Newborn Hearing Screening MB11 Classic E 12a 2 1 1 doc Operating Instructions MB 11 Classic Manual of Basic Audiometry Lloyd L
52. signing the MAICO MB 11 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 MB 11 Classic 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 MB 11 Classic If you have problems or have ideas for further improvements please get in touch with us Simply call Your MAICO team MB11_Classic_E_12a_2 1 1 doc 3 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 2 Important safety instructions The MAICO MB 11 Classic is designed to be used only by skilled personnel Audiologists Physicians or other trained personnel No person should attempt to use this instrument without the necessary knowledge and training to understand how this equipment is to be properly utilized and interpreted The MAICO MB 11 Classic is specified according to IEC 601 1 safety against electrical hazard This is only guaranteed when the connected notebook computer is pow
53. ssic E 12a 2 1 1 doc 39 851 882 2 01 12 M Operating Instructions MB 11 Classic MAICO If the EEG signal is larger than the Artifact limit this measurement will not be used and the numeric value indicated as Artifacts increases by one If the evoked potentials are large you can change the Artifact limit with the mouse by clicking on the arrow right of the Artitact limit box on the top left of the screen Values between 5 uV and 50 uV are selectable It is important to have a good quality EEG during the test This is especially important when there is a suspected hearing loss or the estimated evoked potentials are low In this case do not increase the artifact threshold but try to calm the baby You could also consider testing the baby at another time when the baby is Sleeping Figure 40 shows an example of a test screen for the Time Step Stimulus The analysis time is 40 ms The corresponding wave V responses should occur in the range of the respective white areas Above the white areas are the corresponding click levels Blue stands for the left ear and red for the right ear The magnitude of the curve can be adjusted by changing the Amplitude value trom the pull down menu on the left side of the screen Values between 0 1 uV and 1 1 uV are selectable Accepted 2400 Artifacts 10 Artifact limit 20 pV Amplitude 0 5 pV n f f advanced A Stimulus Level 70 dBHL Right Ear M Click Tim
54. the late cortical potentials require the patient to be awake and alert For click evoked brainstem potentials see Figure 1 5 to 6 typical waves each marked with Roman numerals after Jewett are received with the following approximated source points in the auditory pathway Spiral ganglia Il Auditory nerve cranial nerve VIII leaving the internal meatus IL Ventral cochlear nucleus VCN IV Superior olivary complex SOC and initial section of lateral lemniscus LL V Lateral lemniscus LL ascending section VI Inferior colliculus MB11 Classic E 12a 2 1 1 doc 6 851 882 2 01 12 Operating Instructions MB 11 Classic Latenz ms I II III IV V VI VII I III I V 2 CsS681 3 8048 A 1 6 2 6 3 6 5 2 5 5 2 00 3 88 V u IY p I A0dd A 0 CR CRE CORRE RE COUPE CRE AU RE ROSE CN CS EE LORS ee Q o 4 5 R 10 12 14 16 A Figure 1 Example of a typical low filter ABR potential Important for diagnoses are waves I Ill and V with approximate latencies of 2ms 4ms and 6ms Wave V Is generally the largest and is the only one that can be recorded at levels near the hearing threshold see Figure 1 The latency of all waves increases with decreasing stimulation intensity sound pressure and is generally a better indicator than the wave amplitude which decreases with the stimulation intensity but with a less characteristic pattern The inter peak latency the temporal interlude of waves and Ill l Ill and an
55. three of the electrodes and the eartips should be removed carefully to avoid any discomfort or pain of the patient First remove the eartips to resume normal communication with the patient Subsequently remove the insert phones clipped onto the patient s clothes Unclip all the electrodes cables For removal of the electrodes inform the patient in advance and ask for the patient s cooperation Then using the thumb and the index finger stretch the skin surrounding the electrode pad lightly and with the other hand using a gentle force to pull the electrode pads off the patient s skin with a down upward movement For hygienic reason the electrodes and earphones are for single use only Please use brand new electrode pads and earphones for every new patient to avoid any contamination or transmission of diseases MB11_Classic_E_12a_2 1 1 doc 22 851 882 2 01 12 Operating Instructions MB 11 Classic MB 11 Patient EE bom Last name First name mm dd yyyy O Pat ID Examiner ___ Tracking data MAICO R Ear L C advanced MB 11 BERAphone sjn 1234567 01 22 2008 Figure 18 MB 11 program start screen Enter or load patient data Next click on Measure The measurement screen opens see Figure 19 C advanced 8 Stimulus Level 35 dBHL AA 9 10 2 320 so a m a ue Ps 100 1 eo 130 34 Iso 160 170 no Test stopped MAICO Other Ear Start Measurement Quit M811 B
56. tical problems with repeated testing Sturzebecher E Cebulla M and Elberling C Int J Audiol 42 2 110 7 2005 MB11_Classic_E_12a_2 1 1 doc 59 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 14 Warranty Maintenance and After Sales Service The MB 11 Classic ABR Screener 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 defects in material and workmanship for a period of one year from date of delivery of the instrument to the original purchaser The MB 11 Classic 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 the audiometer should be checked and calibrated at least once a year This check has to be carried out by your dealer When returning the instrument for repairs it is essential to send all the components as well Send the device to your dealer or to a service center authorized by your dealer Please include a detailed description of faults In order to prevent damage in transit please use the original packing if possible when returning the instrument The custom
57. uch screen The MB 11 Classic program can be operated with the mouse by pointing and clicking on the required input field or button on the screen It is also possible to jump with the lt TAB gt key from field to field The actual position is shown as highlighted Pressing the Enter key activates the actual field or button If you use a touch screen you can run the program by touching the appropriate field on the screen Very fast operation is possible by using the keyboard short cuts Press the lt ALT gt key together with the underlined letter of the required button l e to start the measure press the keys lt ALT gt and lt M gt together Alt F File Alt S Settings Alt A About AIt N New Alt C Search Load trom Database Alt T Add to Today s list Alt R Right Ear Alt L Left Ear Alt E Change Ear Alt D Display Today s list Alt M Start Measurement Alt S Stop Measurement Alt Q Quit Alt W Show Measurements Alt P Print Ctrl U USB Pop up window with the connected devices Ctrl B Beep at the end of the measurement MB11_ Classic E 12a 2 1 1 doc 16 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 4 6 Registry of new patient data iw MB11 Maico Mary Born 09 01 2008 Age O day s Palins Ed File Settings About MB 11 Patient New Add to Today s List splay Todays List Show Measurements Last name First name mm dd yyyy Pat ID Screener ISER bi Tracking UE F
58. w MB11_ Classic E 12a 2 1 1 doc 34 Patio Last name MAICO Fest name Meca Date of beth 01 22 2008 Tine of beth Berth weight gams Midtete beth code sire beth Race White v Nursery type Weal baby v Ineurance code Unknown v Parents permission for screening test C OK Figure 32 Tracking data 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 6 3 Advanced Tracking data Advanced tracking data Mother s data Last name date of birth Phone City Town D Zip code State Alternate contact Last name Phone City Town Zip code State Notes First name Maiden name Language Unknown Address 1 Address 2 Risk indicator s Family history C Weight lt 1500g L Bact meningitis C Ototoxic medic _ Mech ventilation C Abnorm apgar sc C Nicu CI Stigmata C Hyperbilirubinemia C Congen infection C Cranio facial anom C Head trauma Recu otitis media C Syndr ass w I Care giver concern L Neonatal ind C First name Language Unknown Other Relationship to mother Address 1 Region unique ID Address 2 J ist tracking variable _ 2st tracking variable OK cancel Figure 33 Advanced tracking data Inout of advanced tracking data is optional and depends on the requirements of the responsible tracking center 6 4 The export functions of the MB 11 databas
59. ware Boot the PC and wait until the operating system finishes the start process Please note that the MB11 is only supported by MS Windows 2000 SP4 on up and MS Windows XP SP1 We strongly recommend MS Windows XP The following installation guide bases on the use of MS Windows XP Install the MB 11 Software with the USB driver Tiles Please note that you need administration rights for software installation Install the MB 11 Software before connecting the MB 11 with the USB port Connect the MB 11 with the USB port of your PC and check that the red LED lights up If this LED does not light up ensure that your USB port supports high powered USB devices or change the USB port and try again Also see the note above about using USB ports After a few seconds the system will show a message about a newly found USB device MAICO MB 11 Put in the installation CD and follow the instructions You can also install the software by start of the setup exe direct from CD 9 3 Computer Settings for optimal performance To get the best possible power for the MB 11 Classic it might be necessary to change the properties of the used computer notebook systems For questions please contact your local dealer MB11 Classic E_12a 2 1 1 doc 44 851 882 2 01 12 MA Operating Instructions MB 11 Classic MAICO 10 Care and maintenance of the instrument Cleaning the instrument The MB 11 Classic requires minimal cleaning However it
60. yle L and Kaplan Harriet Baltimore University Park Press 1980 Manual for Clinical Evaluation Jerger Susan and James Jerger Boston College Hill Press 1981 Katz Jack Baltimore William amp Wilkins 1994 Roeser Ross J New York Stuttgart Thieme 1996 Silam Shlomo and Silvermann Carol A San Diego London Singular Publishing Group 1997 Hamill T A Hussung R A and Sammeth C A Ear and Hearing 12 4 229 234 St rzebecher E Cebulla M and Elberling C Int J Audiol 42 2 110 7 2005 Cebulla M St rzebecher E and Elberling C J Am Acad Audiol 17 93 103 2006 St rzebecher E Cebulla M Elberling C and Berger T J Am Acad Audiol 17 448 461 2006 Cebulla M St rzebecher E and Elberling C J Am Acad Audiol 43 851 882 2 01 12 MAICO MA Operating Instructions MB 11 Classic 9 Installation and Settings 9 1 USB Specifications The MB11 is a high powered device that requires a USB port with 500 mA dc current over the Vysp line Passive USB hubs without an internal or separate power supply do not work with the MB 11 Classic We recommend using a USB port directly on the PC or notebook computer In most cases these ports allow the use of high powered functions devices If you use additional USB devices on your PC and the MB11 does not work or bothers the function of parallel used USB devices try another USB port to change the USB hub output 9 2 Installation of MB 11 Soft

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