Longitudinal extent of ISI |
L133
|
Actual number of segments involved |
0–4 |
|
L22,3,4,8,9,25,26,30,31,37
|
One or more segments |
0 |
No ISI |
|
|
1 |
Focal/single segment ISI |
|
|
2 |
Multisegmental ISI |
L332
|
With T1-weighted changes |
1 |
1 disc space + normal T1W image |
|
|
2 |
>1 disc space + normal T1W image |
|
|
3 |
T1W hypointensity |
Qualitative |
Q133
|
Marginal pattern of ISI |
1 |
Localized |
|
|
2 |
Diffuse |
Q236
|
ISI delineation |
0 |
No signal change |
|
|
1 |
Diffuse signal change |
|
|
2 |
Focal signal change |
Q32,5,10,13,34,35
|
ISI intensity and border |
0 |
No change |
|
|
1 |
Faint, fuzzy border |
|
|
2 |
Intense, well-defined border |
Q49,28
|
Intensity of ISI |
0 |
None |
|
|
1 |
Slight |
|
|
2 |
Moderate |
|
|
3 |
Intense |
|
|
4 |
Very intense |
Other classifications |
O129
|
Axial appearance |
SEA |
Snake-eye appearance |
|
|
NSEA |
Non snake-eye appearance |
O227
|
Position of ISI |
Group A |
ISI in gray matter only |
|
|
Group B |
ISI in gray and white matter |
O338
|
T2W signal intensity ratio |
Group 1 |
<1.32 |
|
|
Group 2 |
≥1.32 and <1.68 |
|
|
Group 3 |
≥1.68 |