| Collateral grading | p Value | |||
| Poor (grade 0–1) (n = 7) | Intermediate (grade 2–3) (n = 20) | Good (grade 4) (n = 17) | ||
| Male sex (n (%)) | 5 (71.4) | 7 (35.0) | 7 (41.2) | 0.288 |
| Age (y) | 60.3 (16.0) | 72.2 (13.8) | 58.5 (24.5) | 0.106 |
| NIHSS score | 15.4 (6.5) | 18.5 (6.6) | 14.5 (5.6) | 0.148 |
| Site of occlusion | ||||
| Carotid bifurcation | 1 | 1 | 2 | |
| Carotid intracranial | 2 | 6 | 2 | |
| Proximal M1 | 2 | 4 | 9 | |
| Distal M1 | 1 | 4 | 4 | |
| Distal MCA | 1 | 5 | – | |
| Mechanisms of stroke | 0.166 | |||
| Cardioembolic | 4 | 16 | 9 | |
| Large artery atherosclerotic | 3 | 4 | 5 | |
| Other | – | – | 3 | |
| Mode of treatment | ||||
| Fibrinolysis | 1 | 6 | 3 | |
| Endovascular thrombectomy | 5 | 12 | 10 | |
| Combined | 1 | 2 | 4 | |
| TIMI grade | ||||
| TIMI 0–1 | 3 | 5 | 1 | |
| TIMI 2 | 4 | 10 | 9 | |
| TIMI 3 | 0 | 5 | 7 | |
| Pretreatment ischaemic zone (ml) | ||||
| Initial DWI lesion volume | 62.9 (65.2) | 35.8 (26.4) | 27.9 (56.6) | 0.052 |
| Initial penumbra volume | 92.8 (57.0) | 57.9 (50.4) | 51.0 (51.5) | 0.285 |
| Initial “benign oligaemia” volume | 19.7 (18.3) | 30.3 (36.8) | 45.8 (34.7) | 0.170 |
| Degree of mismatch (%)* | 67.6 (25.6) | 48.8 (33.4) | 55.3 (43.8) | 0.466 |
| Presence of mismatch (n (%))† | 7 (100) | 14 (70) | 11 (64.7) | 0.258 |
| Severity of perfusion defect‡ | 4.8 (3.6) | 3.8 (4.4) | 1.0 (1.2) | 0.005 |
Values are mean (SD) unless otherwise stated.
*Pretreatment PWI lesion volume exceeding pretreatment DWI lesion volume: [(PWI volume−DWI volume)/PWI volume×100].
†When the area of PWI lesion is greater than DWI lesion by 20% or more.
‡Ratio of initial penumbra volume versus initial “benign oligaemia” volume: [PWI volume of Tmax ⩾4 s/PWI volume of Tmax ⩾2 but <4 s). A high score means that the area of hypoperfusion consisted of severely hypoperfused regions in terms of severity.
DWI, diffusion weighted imaging; M1, proximal portion of middle cerebral artery; MCA, middle cerebral artery; NIHSS, National Institute of Health Stroke Scale; PWI, perfusion weighted imaging; TIMI scale, Thrombolysis in Myocardial Infarction scale.