|
Degree of
Stenosis (%)
|
|
|
|
Normal
|
|
<50
|
|
50-69
|
|
≥70 but
less than
|
|
near occlusion
|
|
Near occlusion
|
|
Total Occlusion
|
|
|
|
|
|
Primary Parameters
|
ICA PSV
(cm/sec)
|
Plaque Estimate
(96)*
|
|
|
|
|
<125
|
None
|
|
<125
|
<50
|
|
125-230
|
≥50
|
|
>230
|
≥50
|
|
|
|
|
High, low,
or undetectable
|
Visible
|
|
Undetectable
|
Visible, no
detectable
lumen
|
|
Additional
Parameters
|
ICA/CCA PSV
Ratio
|
ICA EDV
(cm/sec)
|
|
|
|
|
<2.0
|
<40
|
|
<2.0
|
<40
|
|
2.0-4.0
|
40-100
|
|
>4.0
|
>100
|
|
|
|
|
Variable
|
Variable
|
|
Not applicable
|
Not applicable
|
|
|
|
|
|
|
|