Programming and Coding Flashcards
Telemetry
Confirms proper communication between the processor and the electrodes
AB and Cochlear:”impedance”
Medel: “telemetry”
Neural response assessment
Electrophysiology response from nerve in response to electrode stim
Useful for pediatrics who can’t give subjective measurements
T levels
Measures threshold for sound on each electrode (only cochlear devices)
Measures the lowest amount of electricity needed to be perceived as sound
C or M levels
Comfort levels measured using a scale
-Upper loudness levels.
Speech strategies
Different methods of stimulation that can produce diff perceptions from the patient
- sequential
- simultaneous
- both
Connecting equipment
You’ll need:
- computerized processing unit/ interface (cpu/cui); the “pod” that allows the computer to communicate with the processor
- implant
- processor
- the patient
Prepare equipment: AB
- Verify connection of components: coil to cable to processor
- Initialize processor
- which ear, modality of use (bilateral, unilateral, bimodal)
- do this when loading/reassigning a processor - Condition electrode array
Stimulate all channels at the same time
Gets rid of buildup around array
Perform this at activation, 1wk follow-up, returning on channel
Prepare equipment: Cochlear and medel
- Verify connection of components: coil to cable to processor
- Reset processor as needed
Impedance
Stimulus parameters: current, voltage, stim. Width
Material of electrode surface: (an inverse relationship) narrower contact, more impedance
Nature of the medium of transmission is specific to each electrode: air vs tissue
Measures the opposition to electrical, current flow
Impedance (kiloOhms)=voltage/current
Voltage= impedance x current
When current is cons at increase in impedance will increase voltage
More resistance to flow = higher impedance
Deactivated electrodes
Short electrodes (-<1kOhmn)
- wires touching and likely to send stim across channels
- always in pairs
- turn off and leave off forever
Abnormally high impedance (>30kOhmn)
- broken wire
- air bubble; current can’t travel through air—> remeasure post stimulation
- may decrease with use or by increasing the pulse width
NRT
Neural Response Telemetry
-Cochlear specific
-use of the electrically evoked compound action potential
—gross potential that reflects synchronous firing of a large # of electrically stimulate n8 fibers
—-reflective of wave I of acoustic ABR and comfort levels or upper dynamic range
AB: Neural response imaging (NRI)
Auto NRT
Cochlear Specific
Steps:
1. Select # of channels to run (3, 5,9) a low, mid and high. Running all will take a long time
- Click measure
- Watch measurements and pt reaction
- Prepare to skip channels if pt. Reports discomfort
- Software will move on to next channel if stimulation reaches compliance w/o achieving a response
Auditory neuropathy won’t have NRT
No need to measure later because they should be stable
Terminology
Programming/mapping: Measuring thresholds, tolerance levels, assessing implant status
MAPs: configurations of current units (CU); processing strategies; stimulation rate
Programs: configurations of MAPs; similar of hearing aid programs;use of different programs
Flex NRI
AB specific
NRI= Neural Response Imaging
1. Select channels to stimulate on (avoid most basal @ activation- build up)
2. Recording channel is 2 apical from stim
3. Select level of ordering
–low to high (awake pt.)
–high to low (sedated/surgery in OR)
4. Set min and max stim levels (100-250 uV)
-look for 3 repations of response per channel
5. Crates EP Growth FUnction (best regression line)
6. tNRI corresponds to M levels (not as nicelys to C levels for Cochlear)
NRI/NRT not in MedEl
Clinical Utility of NRT/NRI
- Stable over time
- Used w/ impedances to see if change in performance is due to device function or neural responsiveness; Pt not doing well and impedances are weird, recheck this and if abnormal, may indicate a soft failure.
- Measure w/in first few months of stim (baseline)–> annually/bi-annually afterwords
- loosely correlates with Ms/Cs as a guide to max comfort levels
- Can assess pitch at activations “same vs diffierent” or high vs low
Terminology per company
Cochlear:
Ts and Cs are required
AB/MedEL: Ts are optiona (will be interpolated from Ms) l and Ms are required
SF thresholds per compant
Cochlear: 20-25 (slight)
AB/M: 30-35 (mild)