Table 1 Semiquantitative histology scores
Attribute | Score | Description of assigned score |
|---|---|---|
Injury score | 0 | No injury |
1 | < 25% of the vessel circumference showing disruption of the EEL, IEL, or media respectively | |
2 | 25–50% of the vessel circumference showing disruption of the EEL, IEL, or media respectively | |
3 | > 50% of the vessel circumference showing disruption of the EEL, IEL, or media respectively | |
Thrombus (platelets/fibrin) | 0 | None |
1 | Minimal focal | |
2 | Mild multifocal | |
3 | Moderate regionally diffuse | |
4 | Severe marked diffuse total occlusion | |
Neointimal/medial fibrin deposition | 0 | None to focal interstitial fibrin minimal spotting of fibrin generally consistent with background levels |
1 | < 10% of circumference showing interstitial fibrin | |
2 | 10–25% of circumference showing interstitial fibrin | |
3 | > 25% of the circumference showing interstitial fibrin | |
Red blood cell extravasation score | 0 | No red blood cell extravasation |
1 | < 25% red blood cell extravasation | |
2 | 25–50% red blood cell extravasation showing disruption of the EEL, IEL, and media, respectively | |
3 | > 50% red blood cell extravasation | |
Calcification | 0 | None |
1 | Focal with < 10% of the region affected | |
2 | Multifocal with 10–25% of the region affected | |
3 | Regionally diffuse with 26–30% of the region affected | |
4 | Regionally diffuse with > 30% of the region affected | |
Endothelial loss | 0 | None |
1 | < 25% of the circumference | |
2 | 25–50% of the circumference | |
3 | 51–75% of the circumference | |
4 | > 75% of the circumference | |
Adventitial inflammation score | 0 | No inflammation to minimal interspersed inflammatory cells |
1 | Mild peripheral inflammatory infiltration or focally moderated in < 25% of adventitial area | |
2 | Moderate peripheral inflammatory infiltration or focally marked in 25–50% of adventitial area | |
3 | Heavy peripheral inflammatory infiltration or focally marked in > 50% of adventitial area |