Click ABR

You may need to click on the ABR to see it in full size.  This is a bit challenging; wave V is not the largest of the waves by any means.  (For a baby, that’s not unusual, but by age 2, that is a bit atypical.)  Use the previously provided Excel file on expected wave latencies to help you.  At the highest intensities, V is in the range expected.  Work backwards to find III and I (labeling I is easy.)  Notice that the left and right ears are tested at different intensities.  A lower intensity click was also used.

 

 

 

  • What is the approximate latency of wave I and wave V for the left ear (trace 13: 65 LB, the trace that is the summation of trace 4 and trace 1, the condensation and rarefaction click-evoked ABRs)?  What is the I-V interpeak latency?
  • Mark wave V for the right ear, 65 dB nHL summation run (run 12). What is the latency?
  • Is a similar latency response seen for the right ear when testing at 65 dB nHL?
  • What is the latency observed when the click is increased to 85 dB nHL?  Compare that to the left 65 latency and discuss.
  • The ABRs for 20 dB nHL clicks are shown below the 65 dB click runs in the traces above.  Discuss your interpretation of these responses, and correlate them to your observation of the higher intensity click runs.
  • Were the optimal filter settings used?