Wave

Location

I

Auditory nerve

II

Cochlear nucleus

III

Superior olive

IV

Lateral lemnisci

V

Inferior colliculus

Channel 1

Ai-CZ

Channel 2

Ac-CZ

Channel 3

Ai-Ac

Channel 4

Inion-CZ

Wave

Mean

Range

Wave I

1.62

1.26-1.98

Wave II

2.80

2.23-3.37

Wave III

3.75

3.24-4.26

Wave IV

4.84

4.15-5.53

Wave IV/V

5.27

4.61-5.93

Wave V

5.62

4.93-6.31

I-V (Age<60)

I-V (Age<60)

I-III

2.63

I-IV/V

4.32

III-V

2.31

Abnormal I-III IPL

This abnormality suggests the presence of a conduction defect in the brainstem auditory system between the eighth nerve close to the cochlea and the lower pons.

Abnormal III-V IPL

This abnormality suggests the presence of a conduction defect in the brainstem auditory system between the lower pons and the midbrain.

I absent & III-V is normal

Wave I (the eighth nerve activation potential) could not be recorded. This is usually due to a peripheral hearing disorder. Because of this, the state of conduction in the brainstem auditory pathway between peripheral eighth nerve and lower pons could not be determined. Lower pons to midbrain conduction was normal.

IV or V absent or of abnormally low amplitude

This abnormality suggests the presence of a conduction defect in the brainstem auditory system rostral to the lower pons.

Absent II, III, IV and V with normal I

This abnormality indicates a significant lack of function in brainstem auditory tracts.