Auditory SceneCochlear Implant Fitting Simulator
Meet the patient in the fitting room; read the operative note, examine the incision site, check the sound processor, the coil and the magnet strength, and connect the programming interface. In the fitting software, run impedance telemetry and measure ECAP, ESRT and eABR; set the T and C levels on each electrode and balance the loudness. Verify in live mode and in the sound field, and load the programs onto the processor. When you finish, your program and your findings are compared with the patient’s actual values.
Works on computers and tablets · the 3D scene needs an up-to-date browser
- 15 clinical cases
- 9 baby and child cases
- 3 practice modes
- ECAP, ESRT and eABR
- Data logging
- A4 report and class code
Before you start
Four short notes to help you use the simulator smoothly.
Computer or tablet
The 3D fitting room, the patient and the fitting software have to be visible at the same time, so the simulator does not open on a phone; hold your tablet in landscape.
The first load takes a few seconds
The patient, parent, baby and room models load with the page. The 3D view needs an up-to-date browser with WebGL support.
Sound is optional
The fitting software makes short beeps when a stimulus is sent; these sounds do not represent what the patient hears and are not calibrated. What the patient and the audiologist say is shown in speech bubbles. You can mute the sound with the button in the top bar.
For educational use
This is a simulation; it does not replace clinical programming software or a diagnostic tool. The implant (Ä°A-Ä°22) and the fitting software are fictional; the screen layout is adapted from software used in the clinic.
How does it work?
The flow of a real programming session: prepare the patient and the device, measure, set up the program, then verify and assess.
- 1
Choose the case and the mode
Pick one of the 15 clinical cases or a blind case; set the practice mode (Learning, Guided, Field), then bring the patient from the waiting room into the fitting room.
- 2
Prepare the session
Read the operative note and examine the incision site. Check the sound processor’s battery and microphone and the coil cable, choose the magnet strength and connect the programming interface. The processor, cable and coil are shown on the patient’s head; the indicator light flashes according to the settings.
- 3
Measure and program
Find short and open circuits with impedance telemetry. Run ECAP, ESRT and eABR measurements with their parameters. Present stimuli on each electrode to set the T and C levels and balance the loudness; adjust the strategy, stimulation rate, pulse width and frequency bands.
- 4
Verify and assess
In live mode, get the patient’s comments on sound quality; in the sound field, measure aided thresholds and the Ling Six sounds. Adjust the processor settings and load the programs. Submit your finding and recommendations; the program, the finding, the recommendations and the procedural steps are scored separately.
Cases
The cases fall into four groups: postlingual adults, prelingual children, infants and patients who cannot cooperate, and difficult cases and troubleshooting. Each case’s actual T and C profile, impedances and objective thresholds are generated by the engine; you do not see them, you find them by measuring.
There is also a Blind case option: the case is picked at random and its name is hidden. Blind cases run in Free mode only; you learn the expected finding when you submit your assessment.
Preparation and the 3D fitting room
The checks made before programming begins determine how reliable the measurements are and how comfortable the patient is.
Patient and hearing aid
- Operative noteIs the insertion complete, how many electrodes are in the cochlea, and how many weeks have passed since surgery? With a partial insertion, electrodes outside the cochlea are not stimulated.
- Incision siteIf there is redness, swelling or discharge, the patient is referred to the physician before programming; initial activation is not done until healing is complete.
- Sound processorThe battery and microphone are checked. With a weak battery the processor’s indicator light flashes orange; measurement does not start until the battery has been changed.
- Coil and magnetCable integrity is checked; the magnet is chosen strong enough to hold the coil but not so strong that it presses on the skin.
- Programming interfaceTelemetry and programming are not possible until the processor is connected to the computer. During behavioural measurement the processor microphone is kept off.
Infants and young children
The baby sits in a high chair in front of the mother, with the implanted side visible to the audiologist. For young children, the behavioural method is chosen according to age.
- Behaviour observation and APRStopping sucking, searching for the sound, smiling, crying, trying to remove the coil. A reflex closing of the eyelids in response to a sudden loud stimulus (auropalpebral reflex, APR) shows that discomfort is beginning; the C level is set 7-15% below the level at which the APR is seen.
- Objective measurementsECAP thresholds give the shape of the profile and the starting level; ESRT thresholds are closely related to the C level. If there is fluid in the middle ear, the reflex cannot be recorded.
- VRA and play audiometryIn visual reinforcement audiometry, the screen lights up when the child turns towards the sound; in conditioned play audiometry, the child puts a ring on the peg on hearing the sound.
- Data loggingHours of use, coil-off time and the distribution of listening environments objectively complement what the family reports. In young children, the target is all waking hours.
Fitting software
The Ä°A-Ä°22 Fitting Software running on the laptop on the desk. Its layout is adapted from programming software used in the clinic; in the Turkish version, the English equivalents are shown next to the Turkish names.
| Section | In the simulator |
|---|---|
| DashboardPatient, processor, data logging | Patient and implant details, electrode status on a cochlea diagram; in data logging, hours of use, coil-off time, six listening environments and the input level distribution. |
| MeasurementImpedance and ECAP; ESRT and eABR optional | Common ground impedance and the field telemetry heat map. In ECAP measurement, probe, masker and recording parameters (pulse width, rate, masker level and masker advance, recording electrode, gain, delay, averaging), automatic threshold search, ECAP responses and the amplitude growth function. ESRT and eABR are not done in every session; they are optional, with their own parameters. |
| FittingGlobal, Comfort, Threshold, Detailed fitting, Live mode, Verification | CL-frequency graph and electrode columns; presenting stimuli on bands and on individual electrodes, interpolation, master volume, bass and treble, and loudness balancing at follow-up sessions. Live mode and live voice check, aided thresholds in the sound field and the Ling Six sounds. From the bar at the bottom, the level table, strategy, frequency bands, maplaw and sound processing open full screen. |
| CompletionProcessor settings and loading programs | Four program slots, preprocessing (automatic scene classification, channel-based automatic gain, automatic sensitivity control, noise and wind noise reduction), indicator light and button lock; saving the MAP, progressive programs at initial activation and loading the programs onto the processor. |
| Fitting AssistantSolutions by complaint | Sound quality complaints and, for each, the steps to try in order; the sequences were arranged by comparing them with the literature. |
Criteria used by the simulator
The numerical criteria were chosen to agree with lecture notes and the literature. The stimulus unit CL (current level) is representative; values may differ between manufacturers and protocols.
| Criterion | Value |
|---|---|
| Current levelCL | 0 CL is about 10 µA and 255 CL about 1750 µA; the scale is logarithmic. Charge (nC) = current (µA) × pulse width (µs) / 1000. |
| ImpedanceTelemetry | Normal range about 4-15 kΩ; 1 kΩ or less is a short circuit, 20 kΩ or more an open circuit. Electrodes with abnormal impedance are deactivated. With high impedance the compliance voltage can be exceeded. |
| ECAPECAP threshold | N1 0.2-0.5 ms, P2 about 0.6-0.8 ms. The threshold lies between behavioural T and C: on average at 91% of the dynamic range in adults and at 53% in children. The masker is presented about 10 CL stronger than the probe and 400 µs before it. |
| ESRTStapedial reflex | Normal middle ear function is required; the probe is placed in the opposite ear. The C level is set 5-15% below the reflex threshold. |
| APRAuropalpebral reflex | Reflex closing of the eyelids in response to a sudden loud stimulus; the C level is set 7-15% below the level at which the APR is seen. |
| eABRWave V | II about 1.30 ms, III about 2.10 ms, V about 3.75 ms; 1.5-2 ms shorter than in the acoustic ABR. The threshold is close to behavioural T. |
| Pulse widthStrength-duration relationship | When the pulse width is increased from 25 µs to 50 µs, T and C fall by about 30 CL. With facial nerve stimulation the level can be lowered and the pulse width increased; bipolar stimulation needs more current. |
| VerificationSound field and Ling Six sounds | Aided thresholds are expected to fall within 20-30 dB HL. Detection of the Ling Six sounds shows that the speech frequencies are covered. |
| Data loggingHours of use | The target is at least 10 hours a day in adults and all waking hours (about 12 hours) in young children. Most of the time is spent at inputs of 50-69 dB SPL. |
Modes and score
You can practise the same case with different levels of support. Your score looks not only at the program but also at how you ran the session.
Practice mode
- LearningThe step-by-step guide is open: preparation, impedance, objective measurement, T and C levels, balancing, live mode, verification, processor settings and loading programs.
- GuidedYou do the steps in any order you like; short explanations remain in the preparation steps.
- FieldThere is no guidance; you see only the software’s own warnings. Blind cases run in this mode.
How is the score calculated?
- 1Program (%40)How well the T and C levels on active electrodes match the patient’s actual levels; electrodes that should be deactivated.
- 2Finding and recommendations (40%)Your main finding and recommendations such as follow-up, counselling and referral, compared with the expected ones.
- 3Technique (20%)Preparation, impedance, objective measurement, live mode, sound field, Ling Six sounds, data logging, processor settings suited to the patient, saving the MAP and loading programs.
Results are kept only in your own browser. You can download the A4 report and send your result and report to your instructor with the class code.
Frequently asked questions
It is the adjustment of the sound processor so that it converts sounds into electrical stimulation suited to the patient on each electrode. For each electrode, the threshold at which the patient first hears the stimulus (T) and the highest level they can listen to without discomfort (C) are determined; together with the coding parameters, these values make up the program (MAP).
Initial activation takes place a few weeks after surgery. The levels change as the patient gets used to sound, so follow-up appointments are needed frequently in the first months and less often after that.
In adults, a stimulus is presented and the patient is asked to rate it on a loudness scale: T is the softest level heard, and C is the level that is loud but comfortable to listen to. In children, play audiometry, visual reinforcement audiometry or behaviour observation is used, depending on age.
Objective measurements (ECAP, ESRT, eABR) provide guidance but are not used on their own as a substitute for the levels. Loudness is then balanced between neighbouring electrodes, and the program is verified in live mode.
ECAP measurement records the compound response of the auditory nerve to an electrical stimulus, using the recording system inside the implant. For this response to be visible, a certain number of nerve fibres must be stimulated simultaneously; this is why its threshold is above the behavioural threshold. In young children, the ECAP threshold profile gives the shape of the program and the starting level.
The sound processor records hours of use, the time the coil is off the head, the listening environments the user has been in and changes in sound level. Especially in children who cannot yet talk, it shows objectively how much and in which environments the device is used; if use is low, the reason is looked for first.
Clinical fitting software makes short beeps for as long as a stimulus is being sent; the clinician uses this sound to follow that the stimulus is going out. The beeps in the simulator imitate this behaviour and do not represent the sound the patient hears. You can mute them with the button in the top bar.
No. The simulator runs entirely in your browser; no recording is sent to a server. If you choose to enter your name for the report and the class code, it is stored only in your own browser.
The 3D room, the patient and the fitting software have to be visible at the same time. At phone width this layout becomes unusable, so small screens are blocked on purpose. A tablet works in landscape.
No. What is being programmed here is a virtual patient, and you are the clinician. If you have a question about your own hearing or implant, please contact your implant centre.
Kaynaklar
The simulator’s criteria, measurement models and complaint-solution sequences are based on the sources below.
- Wolfe, J., & Schafer, E. C. Programming Cochlear Implants. Plural Publishing.
- Shapiro, W. H., & Bradham, T. S. (2012). Cochlear implant programming. Otolaryngologic Clinics of North America, 45(1), 111-127.
- Hughes, M. L. (2013). Objective Measures in Cochlear Implants. Plural Publishing.
- Botros, A., van Dijk, B., & Killian, M. (2007). AutoNRT: an automated system that measures ECAP thresholds with the Nucleus Freedom cochlear implant via machine intelligence. Artificial Intelligence in Medicine, 40(1), 15-28.
- van Dijk, B., Botros, A. M., Battmer, R. D., et al. (2007). Clinical results of AutoNRT, a completely automatic ECAP recording system for cochlear implants. Ear and Hearing, 28(4), 558-570.
- Hodges, A. V., Balkany, T. J., Ruth, R. A., Lambert, P. R., Dolan-Ash, S., & Schloffman, J. J. (1997). Electrical middle ear muscle reflex: use in cochlear implant programming. Otolaryngology-Head and Neck Surgery, 117(3), 255-261.
- Busch, T., Vanpoucke, F., & van Wieringen, A. (2017). Auditory environment across the life span of cochlear implant users: insights from data logging. Journal of Speech, Language, and Hearing Research, 60(5), 1362-1377.
If you are ready, the patient is waiting in the fitting room
If you spot an error, if a criterion does not work correctly or if there is a case you would like us to add, write to us: info@isitmeatolyesi.com. The simulator is an open-ended educational project; it grows with your feedback.