Operating Instruction
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Operating Instructions Race Car Tympanometer w/ Audiometer
Maico Diagnosticsi7625 Golden Triangle DriveiEden Prairie, MN 55344iToll Free 888.941.4201 Maico Diagnostic GmbHi Salzufer 13/14i10587 Berlin, GermanyiTelephone ++030 70 71 46 50
Operating Instructions Race Car Tymp w/ Audio Table of Contents
Page
1 Introduction ... 1 2 Description... 2 2.1 2.2 2.3
Tympanometry ...2 Acoustic reflex...3 Audiometric pure tone screening...3
3 Getting started ... 4 3.1 3.2 3.3 3.4 3.5 3.6 3.7
Unpacking...4 Environmental conditions for the RC ...5 Preparing the RC for use ...5 Getting familiar with the RC...6 Calibrate the probe ...9 Getting familiar with the probe ...10 Choose an appropriate ear tip ...11
4 How to create a tympanogram ... 12 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9
The basics of the impedance measurement ...12 Preparing the patient...14 Preparing the measurement ...14 Measuring the tympanogram ...14 How to evaluate the tympanogram display...15 Performing the tympanometry test w/ animation...16 Graphics and screens...16 How to print test results ...18 How to delete the test results...18
5 How to create a tympanogram with high probe tone... 19 5.1 To select high probe tone frequency ...19
6 How to measure the Stapedius reflex ... 20 6.1 6.2 6.3 6.4 6.5 6.6 6.7
The basics of the Stapedius reflex measurement ...20 Preparing the patient...20 Preparing the ipsilateral measurement ...21 Taking the ipsilateral measurement ...22 Preparing the contralateral measurement (optional)...23 How to interpret the reflex display...23 How to print the test result ...24
7 Interpreting test results ... 25 7.1 7.2 7.3
Understanding the printout ...25 Interpreting the tympanometric test result...26 Abnormal Values ...26
8 How to test children ... 28 9 Audiometric pure tone screening ... 29 9.1 9.2
Preparing the patient for the test...29 Audiometer function recommended procedures...29
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Operating Instructions Race Car Tymp w/ Audio 9.3 9.4 9.5
Hearing threshold method...30 RC LCD Screen - Audiometer...31 Audiometric pure tone screening results...31
10 Additional Reading ... 32 11 Individual Setup of the RC... 33 11.1 11.2 11.3 11.4 11.5 11.6
The setup menu ...33 The Tympanometer setup...34 The Setup menu for Reflex Test ...35 The Common Setup Menu ...36 Audiometer Setup Menu ...37 Insert your personal printout data...37
12 Care and maintenance of the instrument ... 38 13 How to change the printer paper ... 39 14 Warranty, maintenance and after-sales service ... 40 14.1 Warranty ...40 14.2 Maintenance ...41
15 Safety regulations ... 43 15.1 Electrical safety:...43 15.2 Measuring accuracy:...43 15.3 Device control: ...43
16 Checklist for subjective device control ... 44 17 Technical Data and Accessories... 45
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Operating Instructions Race Car Tymp w/ Audio 1 Introduction Thank you very much for purchasing a quality Maico product. This automatic Race Car (RC) Tympanometer with Audiometer is manufactured to meet all quality and safety requirements. This user manual should make it as easy as possible for you to become familiar with the functions of the RC. The description of the position (e.g., 5 ) of controls, displays and connections, found again in the text, will make it easier for you to learn how to operate the RC. If you have problems or have ideas for further improvements, please get in touch with us. Simply call. Your MAICO team
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Operating Instructions Race Car Tymp w/ Audio 2 Description The RC is an automatic instrument that is designed for tympanometric and audiometric pure tone screening. Tests done in the tympanometric screening mode measure middle ear mobility and ipsilateral acoustic reflex. Contralateral acoustic reflex is available as an option. Test results are displayed on the front panel LCD (liquid crystal display) screen and may be printed. The RC not only performs all of these impedance screening functions but has the capability of audiometric pure tone screening. Tests done in the audiometric pure tone screening mode measure hearing response levels. The RC offers a full range of frequencies and levels for complete air conduction hearing screening The design of the RC allows rapid and reliable measurements. This equipment is designed for middle ear function screening. PC-Interface: A USB interface for data transfer to a connected computer is built in. musculus 2.1 Tympanometry stapedius hearing Tympanometry is the objective nerve measurement of middle ear middle mobility (compliance) and pressure ear bones within the middle ear system. During the test, a tone (226 Hz or 1000Hz) is presented to the ear ear canal canal by means of the hand-held cochlea ear drum probe. This tone is used to measure middle ear the change in compliance in the middle ear system while the air eustachian tube pressure is varied automatically from a positive value (+200 daPa) to a negative value (-400 daPa Figure 1 The middle ear max.). Maximum compliance of the middle ear system occurs when the pressure in the middle ear cavity is equal to the pressure in the external auditory canal. This is the highest peak of the curve as it is recorded on the chart. The position of the peak on the horizontal axis and on the vertical axis of the chart will provide diagnostic information regarding the function of the middle ear system. Examples of normal and abnormal tympanograms can be found in a later section of this manual. Gradient calculations are reported as the tympanogram width at half of peak compliance expressed in daPa. A “limits” box is available on both the display and printout to aid in diagnosis. Compliance is measured with respect to an equivalent volume of air, with the scientific quantity milliliter (ml). Air pressure is measured in deca-Pascals (daPa). NOTE: 1.02 mm H2O = 1.0 daPa.
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Operating Instructions Race Car Tymp w/ Audio 2.2
Acoustic reflex
An acoustic reflex, or contraction of the Stapedius muscle, occurs under normal conditions when a sufficiently intense sound is presented to the auditory pathway. This contraction of the muscle causes a stiffening of the ossicular chain which changes the compliance of the middle ear system. As in tympanometry, a probe tone is used to measure this change in compliance. When the stimulus presentation and measurement are made in the same ear by means of the probe, this acoustical reflex is referred to as an ipsilateral acoustic reflex. When the stimulus presentation and measurement are made in opposite ears, the reflex is referred to as a contralateral acoustic reflex. For best results, this reflex measurement is automatically conducted at the air pressure value where the compliance peak occurred during the tympanometric test. Stimulus tones of varying intensities at 500, 1000, 2000 or 4000 Hz are presented as short bursts. If a change in compliance greater than 0.05 ml is detected, a reflex is considered present. Because this is an extremely small compliance change, any movement of the probe during the test may produce an artifact (false response). The test result is recorded as Pass/No response, and in graphical form. If the tympanometric results display any abnormal findings, the results of the acoustic reflex testing may be inconclusive and should be interpreted with care. Theoretically, a compliance peak is necessary to observe a reflex at peak pressure.
2.3
Audiometric pure tone screening
The purpose of this test is to measure the intensities of pure tones of various frequencies that a listener is just barely able to detect in an otherwise quiet environment. During screening, tones can be presented at a determined frequency and intensity. The RC can be used to find the lowest response level (threshold) at each frequency. Pass/fail criteria can be decided by following the established standards for your organization.
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Operating Instructions Race Car Tymp w/ Audio 3
Getting started Your RC was carefully inspected and packed for shipping. However, it is good practice to thoroughly inspect the outside of the shipping container for signs of damage. If any damage is noted, please notify the carrier immediately.
3.1
Unpacking
Remove the accessories. Carefully remove the instrument from the shipping carton. Remove the instrument from the plastic bag and inspect the case 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. When the adjuster has completed the inspection, notify the MAICO Special Instrument Distributor you purchased this unit from. Save all the original packing material and the shipping container so the instrument can be properly packaged if it needs to be returned for service or calibration. 3.1.1 Accessories Supplied Please check that all accessories listed below are received in good condition. If any accessories are missing or damaged, immediately notify your MAICO Special Instrument Distributor. Description Part No. Hand-held probe 570G-14 24-count eartips kit: 6613 (4) yellow, 7 mm 6643 (4) green, 9 mm 6644 (4) white, 11 mm 6645 (4) yellow, 13 mm 6646 (4) green, 15 mm 6647 (4) blue, 18 mm 6648 Thermal printer paper 5529 Calibration test cavity 5533 TDH 39 headset 4687 Patient response switch 2169 Operating Instructions 1162-0322 Optional Accessories: Soft-sided carrying case 1035-3002 Contra button phone and cable 4796 Contra TDH 39 phone and cable 4682
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Operating Instructions Race Car Tymp w/ Audio 3.2 Environmental conditions for the RC The RC should be operated in a quiet room. The test room must be at normal temperature, usually 15° C / 59° F to 35° C / 95° F, and the instrument should be switched on about 10 minutes before the first measurement to guarantee precise measuring results. If the device has been cooled down (e.g. during transport), please wait until it has warmed up to room temperature
3.3
Preparing the RC for use
3.3.1 Connect probe and accessories 3
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Connect the probe cable to socket the instrument.
on the rear of
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Insert the plug into the socket and secure the connection by fastening the two screws of the connector.
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Insert the pressure tube into the socket 4 it until it is secure on the socket.
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Put the enclosed main cable into the power connection socket 1 and its main plug into a power socket. The instrument is now operational.
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Connect the headset cable to socket 6 and the rear of the instrument.
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Connect the cable of the patient response switch to socket 8 on the rear of the instrument.
and press
7
on
Figure 2 The probe of the RC
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Operating Instructions Race Car Tymp w/ Audio 3.4
Getting familiar with the RC
7 13
2
4
5
12
8
3
6
1 Figure 3 The controls of the RC
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10
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1
3.4.1 The RC Front Panel Controls 1. 2. 3. 4. 5.
Presents tone stimulus during audiometric testing.
6.
REFLEX = Changes the reflex testing modes from IPSI to CONTRA or NO REFLEX.(Press and hold to change to 1000Hz probe tone for tymponametry.)
7. 8. 9. 10. 11. 12. 13.
MENU = Enters the main menu screen.
PULSE = Turns pulse tone on or off for audiometric testing. TYMP/AUD = Changes modes between tympanogram or audiometric testing PRINT = Prints the test results. L/R = Changes test ears from left to right, or right to left for tympanogram or audiogram. Press and hold for 2 seconds to erase stored tests.
ENTER = Enters the highlighted menu or the highlighted option. 3= Decreases the frequency (Hz) for audiometric testing. 6= Decreases the intensity level (dB) of reflex or audiometric testing. 8= Increases the frequency (Hz) for audiometric testing. 5= Increases the intensity level (dB) of reflex or audiometric testing. MODE =Changes mode from Presenter to Interuptor.
How to use the extended functions is described in chapter 10: “Individual Setup of the RC."
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Operating Instructions Race Car Tymp w/ Audio 3.4.2 The RC Rear Panel Connections 12
11
8
10
7
6
2
4
5
3
9
1
Figure 4 Connectors at the rear of the RC
1.
AC POWER - Connection for AC power cord.
2.
ON/OFF SWITCH - Power switch; 1 is ON, 0 is OFF.
3.
PROBE - Connection for probe cable to rear panel.
4.
PROBE PRESSURE - Pneumatic connection for the probe cable.
5.
CONTRA - Jack for contralateral reflex phone.
6.
AC (R) - Jack for right (red) audiometer phone.
7.
AC (L) - Jack for left (blue) audiometer phone.
8.
PAT - Jack for patient response switch .
9.
USB INTERFACE - Connection for computer interface.
10.
BC – Connection for Bone Conductor.
11.
MIC – Jack for Talk Back Microphone.
12.
CD (L) and (R) – inputs for external CD player.
3.4.3 Switch the instrument on Switch the main switch 2 on. The LCD will show the type of instrument and software version for a moment. Then the basic measuring figure appears. The RC should be switched on about 10 minutes before the first measurement to guarantee precise measuring results. If the device has been cooled down (e.g. during transport), please wait until it has warmed up to room temperature.
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Operating Instructions Race Car Tymp w/ Audio 3.4.4 The display of the RC The test result is shown during the measurement on the LCD. The measurements are saved automatically and can be printed out in a fast and quiet way with the integrated printer. Impedance Right Ipsi In figure 5 the initial empty measurement screen is shown. The measurement screen shows actual settings, test results and the graphical display of the tympanogram and reflexes. From left to right the top line shows the type of test (impedance is shown in Figure 5), the selected test ear (left or right) and the selected reflex test (ipsi, contra (optional) or tympanogram if no reflex test is selected).
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Status READY
ml
Ear Volume 2
Compliance 1
Pressure 0
-600
-300
1
2
80 500 Hz I
Gradient
300 daPa 3
80 1000 Hz I AUTO
4
80 2000 Hz I dB
80 4000 Hz I
Figure 5 The measurement screen of the RC
At the left center, the graph of the tympanogram is shown. At the right, five boxes show the status and test values.
The upper box shows the actual status of the instrument: READY - means that the instrument is ready for testing IN EAR - shows that the probe is inserted in the ear TESTING - means that the test is in progress BLOCKED - means that probe is blocked in the ear LEAKING - indicates that the ear tip does not have a proper seal The boxes below Status show the volume of the ear canal, the compliance, the pressure at maximum compliance and the gradient of the tympanogram when the test has been completed. The four boxes at the bottom of the screen, marked 1 to 4, show the graphical reflex curves after the test. Below each box the test level (figure 5: 80 dB), and the test frequencies (Figure 5: 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz) are displayed. After the frequency an “I” shows that ipsilateral testing is selected. Finally, at the very bottom in figure 5 the word Auto and 80 dB scale is shown. This means that the reflex test level will increase automatically until a reflex is found or the maximum level is reached. With the arrow keys, the test levels can be changed to a fixed level. The dB values below the boxes change accordingly. It is possible to have fixed levels from 70 dB to 100 dB or Auto.
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Operating Instructions Race Car Tymp w/ Audio 3.5 Calibrate the probe Adjust the impedance measuring instrument every day to the actual atmospheric pressure by means of the enclosed calibration volume. The calibration is very easy and takes only 20 seconds. Press the menu key 7 and the main menu (Figure 6) appears on the LCD. Select the menu option Calibration with the arrow keys and press Enter. Follow the instructions on the LCD as shown in figure 7.
Main Menu Tympanometry : Audiometry: Calibration : Setup :
↑ ↓ Change item ENTER Select item
Put the probe tip S without ear tip into the hole of the test cavity labeled 0.5 ml. The text on the display will request that the probe tip be inserted for the 2 ml calibration. Put the probe tip in the 2 ml cavity. Do this again for the 5 ml volume. The RC will automatically change into the tympanometry mode. The basic menu for the impedance measurement appears again and you are ready for measurements.
Calibration Place the probe in the .5 ml cavity.
If the error information Cavity Calibration Out of Range appears during the calibration, please make sure the opening of the probe tip is clean and try to Figure 7 recalibrate the probe. If the error The calibration screen information appears again, the probe or the instrument is probably in need of service. Inform your Maico Special Instrument Distributor to get immediate help.
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Operating Instructions Race Car Tymp w/ Audio 3.6 Getting familiar with the probe The probe of the RC is shown in (Figure 8). The probe head is adjustable to three angles (0°, 60° and 80°). It is adjusted by turning the locking screw T at the bottom of the probe using a coin or a screw driver. Adjust the probe head P by pulling it into the required position until it rests. After it is set to the required position tighten the locking screw again. The probe button M can be used to select the required test ear. The color of the O control light changes accordingly to red (right ear) or blue (left D T EL C N P E R E G S ear). The color of the control light on the probe indicates your current operation. A red control light indicates M B O D E G EL C N P Q E E R S that the right ear is selected. The system is ready for Figure 8 measurements. As soon as The probe of the RC you have put the probe into the auditory canal the control light turns green. Now the test is in progress. Do not change the position of the probe until the green control light goes out indicating the end of the measurement. A blue control light indicates that the left ear is selected. The system is ready for measurements. As soon as you have put the probe into the auditory canal the control light turns green. Now the test is in progress. Do not change the position of the probe until the green control light goes out indicating the end of the measurement. A yellow control light indicates an error. The kind of error is indicated on the LCD under status: LEAKING: The ear tip is not sealed in the auditory canal. Change the position of the probe until the control light turns green. If you are not successful, use a bigger ear tip. BLOCKED: Indicates blockage in the probe opening. Change the position of the probe so that it points straight into the auditory canal until the control light turns green. If you are not successful, check that the probe is not blocked with ear wax.
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Operating Instructions Race Car Tymp w/ Audio Q
The complete probe insert can be changed by pressing the release button . If the probe tip is clogged, you can remove it by opening the fixation ring R . After cleaning the probe tip or attaching a new one, the tip must be fixed again by fastening the fixation ring.
3.7 Choose an appropriate ear tip Choose an ear tip of the appropriate size from the ear tip set. Put the ear tip tightly on the probe tip. The probe tip should end near the end of the ear tip. It should not be inserted more than about 1 mm in the ear tip or protrude out of the ear tip (see Figure 9). By choosing an appropriate ear tip and placing it correctly on the probe you create the basic conditions for measurements without problems and mistakes. Now all preparations are concluded and you can start the impedance and reflex measurement. Please read the following chapters.
min 0 mm max 1 mm
Figure 9 Proper placement of ear tip
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Operating Instructions Race Car Tymp w/ Audio 4 How to create a tympanogram In the following paragraph we will deal shortly with the principle and the background of the impedance measurement to create a better understanding. If you want to begin the measurements immediately, just skip this paragraph and continue reading section 4.3 “Preparing the Measurements.”
4.1 The basics of the impedance measurement The impedance measurement assists in diagnosing of the condition of the middle ear and can therefore not be compared directly with other audiometric tests such as sound or speech audiometry which assists in the measurement of hearing. Furthermore the impedance measurement is an objective measuring method which does not depend on the cooperation of the test person and can therefore not be falsified by the patient.
musculus stapedius
hearing nerve
middle ear bones ear canal ear drum
cochlea
middle ear eustachian tube Figure 1 The middle ear
The two most important impedance measuring methods possible with your RC are tympanometry and the measurement of the Stapedius reflex which is discussed in chapter 5: “How to measure the Stapedius reflex.”
Figure 11 Principle of the impedance measurement
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Operating Instructions Race Car Tymp w/ Audio The impedance measurement examines the acoustic resistance of the middle ear. If the eardrum is hit by a sound, part of the sound is absorbed and sent via middle ear to the inner ear while the other part of the sound is reflected. The stiffer the eardrum, the more sound reflected, and therefor less sound reaches the inner ear. Inside the probe of the impedance measuring instrument a small loudspeaker is installed which emits a tone through a tube (Figure 11: A) into the auditory canal before the eardrum. Another tube (Figure 11: B) is connected to the microphone inside the probe which receives the sound. Together with a third tube (Figure 11: C), all three are inserted nearly to the eardrum and are made airtight against outside pressure by the ear tip. A manometer and a pump, which can produce both positive and negative pressure, are connected with tube C. Less sound is reflected to the microphone when the eardrum is stiff and the eardrum transmits the majority of the sound via the middle ear to the inner ear. The highest compliance is normally reached with an air pressure corresponding to the outside pressure.
2,0 2.0
1.6 1,6 Compliance ( ml)
During a Tympanometery measurement, a continuous change of positive and negative pressure is produced by the pump of the instrument in the outer auditory canal. The compliance is measured simultaneously and shown in a diagram (the tympanogram) which illustrates the compliance in ml over the pressure in daPa. In (Figure 12), the area for normal tympanogram curves is hatched. Here you can see that the highest compliance is reached with normal pressure. When you create positive and negative pressure the eardrum stiffens - the compliance decreases.
1,2 1.2 0,8 0.8 0,4 0.4 00
-300 -200 -100 0 +100 Pressure ( daPa )
Figure 12 Tympanogram (normal curve area is hatched)
So you can draw conclusions on the condition of the middle ear from the shape and the values of the tympanogram.
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Operating Instructions Race Car Tymp w/ Audio 4.2 Preparing the patient Explain to the patient that the measurement is painless and that nothing enters the auditory canal. The patient does not have to respond when there are loud test sounds or when the pressure in the auditory canal changes. In no case should the patient swallow, chew or move during the measurement.
4.3 Preparing the measurement The LCD shows the empty measurement screen for the right ear and the control light of the probe turns red. To measure the left ear, change the side by pressing the L/R key or the probe button M . Then the selected test ear shown in the middle-top of the LCD will change from Right to Left and the control light of the probe will turn blue. Switch off the reflex measurement by pressing the Reflex key 6 . The word Tympanometer must appear at the right top of the display. Make sure the auditory canal is clear. Choose an ear tip according to the size of the auditory canal and put it firmly onto the probe tip (see Figure 9 in chapter 3.7).
4.4 Measuring the tympanogram Take hold of the top of the outer ear and pull it back. Insert the probe with the ear tip into the auditory canal until Impedance Right Tympanometer the control light of the probe is green indicating the start of the Status ml 3 READY test. Do not move the probe until Ear Volume the green light goes out; the 2 patient must not swallow or Compliance speak during the measurement. 1 During the test the LCD will Pressure display the tympanogram on the 0 left side while the test is running Gradient -600 -300 300 daPa and then the values will appear on the right side. After about 4-5 Scale seconds the test is completed Figure 13 and the green light turns off. Measurement screen (only Tympanogram) Now you can remove the probe from the ear. If an error occurs during the measurement the test will stop. If leakage occurs, the control light of the probe turns yellow and Leaking will appear under Status. If the probe is blocked, the control light of the probe turns yellow and Blocked will appear under Status. Please proceed as described in chapter 3.6 “Getting familiar with the probe.” To measure the other ear, change the side by pressing the L/R key or the probe button and repeat the measuring procedure described above with the other ear.
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Operating Instructions Race Car Tymp w/ Audio 4.5 How to evaluate the tympanogram display After having completed a measurement you can see the results on the LCD. On the left side of the display you see a graph of the tympanogram. The area surrounded by the box is valid for “normal” tympanograms. You can change the area or turn it off.
Impedance
3
Right
Tympanometer Status READY
ml
2
Ear Volume 0.94 ml
1
Compliance 0.81 ml
0
Pressure - 37 daPa
-600
For details see chapter 10 “Individual Setup of the RC.”
-300
300 daPa
Gradient 32 daPa
Scale
Figure 14 Display of a normal Tympanogram
In the top-middle of the LCD, the words Right or Left indicate the ear chosen at the moment.
Tympanometer (at the top right) - indicates that the reflex measurement has been switched off. In the boxes to the right the following test measurements are displayed: Ear Volume - indicates the volume of the section of the auditory canal between the ear tip and the eardrum in ml (in the example 0.94 ml). Compliance - indicates the maximum value of the compliance from the tympanogram in ml (in the example 0.81 ml). Pressure - indicates the pressure with the highest measured compliance (in the example -37 daPa). Gradient - calculations are reported as the tympanogram width at half of peak compliance expressed in daPa (in the example 32 daPa).
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Operating Instructions Race Car Tymp w/ Audio 4.6
Performing the tympanometry test w/ animation NOTE: Animation must be turned on in set-up menu (see section 11.4 “The Common Setup Menu“) Press ENTER to activate the RC animation. INSERTING THE PROBE: While the child is distracted by the graphics, Place the hand held probe (with proper ear tip) inside the child’s ear while gently pulling the earlobe down. Check for excess wax or obstructions. Because children have very small ear canals, this allows the operator to maintain a seal easily. • •
NOTE: The ear tip does not need to go into the ear canal. It should only seal the canal opening. Attempt to point the end of the ear tip into the canal, toward the eardrum. Depending on the child, a smaller or larger size ear tip may be needed to secure a proper seal.
4.7
Graphics and screens The Race Car Tympanometer or Race Car Tympanometer W/Audiometer will show different graphics throughout the test. In addition, the status of the test will also be indicated at the top of the screen. When the Insturment is ready to test, the following screen will appear. “Ready“ status will be indicated at the top of this screen.
When the probe is inserted into the ear the status changes to “in ear”. When a proper seal is detected, the test status will change to “testing”. The graphic of the Race Car will also change as displayed below.
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Operating Instructions Race Car Tymp w/ Audio When the test is finished, the following screen will appear.
The actual tympanogram with numerical data will then appear on the screen for review. Impedance
3
Right
Tympanometer Status READY
ml
2
Ear Volume 0.94 ml
1
Compliance 0.81 ml
0
Pressure - 37 daPa
-600
-300
300 daPa
Gradient 32 daPa
Scale
To test the other ear with RC animation, first switch ears with the L/R button, then press ENTER to start the animation. Perform the test the same way as stated above. If a leak is detected during the test, the following graphic will be displayed. “Leaking” will be displayed at the top of the screen.
If the probe tip is blocked (either by wax or up against the ear canal wall), the same graphic will display, but “Blocked” will be displayed at the top of the screen. In either case, remove the probe and re-insert into the ear to re-start the test.
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