Real-ear Measurements with the A-35 Presented by: Kristina Frye Frye Electronics, Inc

Topics Interface from the A-35 Entering an Audiogram and Creating a Target Performing Insertion Gain Measurements Measurements in SPL: Comparing HTLs and UCLs Testing with Visible Speech Testing Open Fit Hearing Aids Doing all this from the FONIX NOAH Module

FP35 Real-ear Screens Audiogram Entry Real-ear SPL Unaided & Aided Insertion Gain Move between these four screens by using NEXT and BACK

Audiogram Entry Screen Amplitude The Audiogram Entry screen is used to enter the patient's audiogram and generate an appropriate target. Frequency F2 — Select HTL/UCL/Bone F3 — Generate Target

NAL-NL1 Target Settings Press MENU and BACK to change target settings Compression Channels (1-18) Aid Limiting (Type of output limiting) Fit Type (Unilateral or Bilateral) Reference (Almost always Head Surface) The Compression and Channels settings have the most impact on the target!

Insertion Gain Testing Press NEXT until you enter the Real-ear Insertion Gain screen

Traditional Real-ear Protocol Measuring the Insertion Gain Response

PROS and CONS of Measuring the Unaided Response Let’s get sidetracked for a few minutes… PROS and CONS of Measuring the Unaided Response

Save Time! To save testing time, you can probably skip the unaided response measurement! Thresholds are measured with an occluded response Targets are generated from those thresholds Many hearing aids alter the ear canal resonance when inserted, so the unaided response is extraneous data

Exceptions When is the unaided response useful? Fitting a mild/moderate loss: Make sure that the hearing aid is proving a benefit to the patient Checking the position of the probe microphone

Back to the Protocol…

Proper Placement of Microphones Ref Mic Above the Pinna Marked 30 mm from the tip for Adults and 25 mm for children This illustrates proper placement of the microphones on the ear. The reference mic is placed on the earhook above the pinna so that the microphone screen is approximately parallel to the pinna opening. The probe tube can be marked at 30 mm from the tip for adults, and about 25 mm for children depending on their size, so that insertion depth is adequate without causing pain by bumping the eardrum. Marking the tube with a red pen also serves as a means to make sure insertion of the hearing aid doesn't push the tube in farther. The probe tube should exit at the inter-tragal notch. Inter-Tragal Notch Probe Mic

Level the Sound Field Speaker Internal sound chamber converts to sound field speaker; should be ear height 12 inches from the speaker at 45° angle Stand away from the patient/loudspeaker during measurements The hearing aid (if silent) and/or probe tube can be inserted during leveling Press F5 and START in the Real-ear Measurement screen to level the sound field speaker

Choose the Curve with F2 Four Curves Available Unaided Ins. Gain #1: 50 dB Ins. Gain #2: 70 dB Ins. Gain #3: 90 dB Selected curve shown above F2

Testing Protocol For Quick Testing, measure only Ins. Gain #2. This measures at average speech level (70 dB SPL) For Complete Testing, measure Ins. Gain #1, #2, and #3 (50, 70, and 90 dB SPL) If no unaided response is measured, the average is automatically substituted

Example of Insertion Gain Meas Prescription: This patient could use more amplification between 2000-6000 Hz!

Overview for Quick Insertion Gain Testing Enter Audiogram Entry screen Press F2 from Opening Screen. Use NEXT and BACK if necessary Input audiogram and generate target Use arrow keys to enter audiogram. Press F3 to generate target. Enter Insertion Gain screen Use NEXT until screen appears Level the sound field speaker Press F5 and START Measure Ins. Gain #2 and fit to target Use F2 to select curve. Press START/STOP to start and stop test If desired, also measure Unaided response and Aided Curve #1 and #3

The Real-ear SPL Protocol Compare the Real-ear Response to HTLs and UCLs on one graph

Real-ear SPL Screen UCLs Target HTLs The Real-Ear SPL screen displays the patient's threshold values, real-ear target, and uncomfortable levels all in one screen in dB SPL. HTLs

Real-ear SPL Measurements Goal: Aided 3 below UCLs Aided 2 meet target Aided 1 above HTLs In a typical hearing aid fitting, AIDED 1 is used at to make sure that soft sounds meet the patient's threshold values. AIDED 2 is used to make sure medium speech meets the target. AIDED 3 is used to make sure that loud sounds are below the patient's uncomfortable levels.

Overview of the SPL Protocol Enter Audiogram Entry screen Press F2 from Opening Screen. Use NEXT and BACK if necessary Input audiogram and generate target Use arrow keys to enter audiogram. Press F3 to generate target. Enter Real-ear SPL screen Use NEXT until screen appears Level the sound field speaker Press F5 and START Measure Aided #1 to compare to HTLs Use F2 to select curve. Press START/STOP to start and stop test Measure Aided #2 to compare to the target Measure Aided #3 to compare to UCLs

Visible Speech Use External Signals such as Live Voice in the real-ear measurements Perform this measurement in the Real-ear SPL screen NEW! Both the real-time response and the average response are displayed

Example of Visible Speech Average Response Real-time Response

Visible Speech Protocol Enter Audiogram Entry screen Press F2 from Opening Screen. Use NEXT and BACK if necessary Input audiogram and generate target Use arrow keys to enter audiogram. Press F3 to generate target. Enter Real-ear SPL screen Use NEXT until screen appears Put analyzer in Spectrum Analysis mode Use F4 to select the source type. Use DOWN arrow to turn source OFF. Perform Visible Speech measurement Press START/STOP to start measurement. Begin speech signal.

Open Fit Hearing Aids Coupler measurements: Use our new Open Fit Coupler! Real-ear measurements: Same protocol but disable the reference microphone

Open Fit Coupler Insert the hearing aid into the coupler as you would into the ear No sealing is necessary Produces a frequency response more like a real-ear response For ANSI measurements to specifications, use HA-1 coupler

Real-ear Measurements Some Open Fit hearing aids interfere with the reference microphone measurement outside the ear (feedback management and/or amplified signal escaping from ear) Disable the REF MIC setting in the real-ear measurement screen local menu Test as usual Expect very little amplification below 1000 Hz. Fit to target only in mid-to-high frequencies

Example of Open Fit Real-ear

Using the FONIX NOAH Module Friendly Windows-based interface Automatically use NOAH audiogram Can send NOAH audiogram to analyzer Perform real-ear and coupler measurements from computer Save all results into NOAH database On Top window: Perform real-ear while adjusting the hearing aid!

Interface

Now for a FONIX NOAH Module Demonstration!