Association between baseline clinical (stroke severity and subtype, age and time to baseline scan) and imaging (structural, perfusion, arterial patency) variables
| CT or MR: | Structural imaging | Perfusion imaging | Angiography | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Variable | ASPECTS score | IST-3 score | Tmax w.r.t. structural lesion* | Tmax ASPECTS score | CBF w.r.t structural lesion* | CBF ASPECTS score | CBV w.r.t. structural lesion* | CBV ASPECTS score | Arterial occlusion |
| NIHSS baseline | −0.67 (−0.77 to −0.52); p<0.0001 | 0.60 (0.44 to 0.73); p<0.0001 | 0.33 (0.11 to 0.52); p=0.004 | −0.63 (−0.75 to −0.47); p<0.0001 | 0.34 (0.12 to 0.53); p=0.003 | −0.61 (−0.74 to −0.45); p<0.0001 | 0.38 (0.16 to 0.56); p=0.00074 | −0.59 (−0.72 to −0.42); p<0.0001 | p<0.0001 |
| OCSP | p<0.0001 | p<0.0001 | p<0.0001 | p<0.0001 | p=0.00025 | p<0.0001 | p=0.00042 | p<0.0001 | p<0.0001 |
| Age (years) | −0.25 (−0.44 to −0.03); p=0.03 | 0.28 (0.06 to 0.47); p=0.01 | 0.19 (−0.04 to 0.41); p=0.10 | −0.27 (−0.47 to −0.04); p=0.02 | 0.19 (−0.04 to 0.40); p=0.09 | −0.27 (−0.47 to −0.05); p=0.02 | 0.26 (0.04 to 0.46); p=0.02 | −0.34 (−0.53 to −0.12); p=0.003 | 0.19 |
| Time to first scan (hours) | 0.07 (−0.16 to 0.29); p=0.57 | −0.10 (−0.32 to 0.14); p=0.41 | −0.21 (−0.42 to 0.03); p=0.08 | 0.18 (−0.06 to 0.39); p=0.14 | −0.22 (−0.43 to 0.02); p=0.07 | 0.20 (−0.03 to 0.41); p=0.09 | −0.08 (−0.31 to 0.16); p=0.51 | 0.11 (−0.13 to 0.34); p=0.36 | 0.56 |
Angiography data analysed by Wilcoxon–Mann–Whitney test, except for OCSP which was analysed by χ2 test. All other associations assessed by Spearman correlation and 95% CI, except for OCSP groups which are compared using the Kruskal–Wallis test.
*Expresses the extent of the perfusion lesion with respect to the structural lesion according to whether there was (a) no visible lesion, (b) a visible lesion that was less than 80% of (c) the same size as, or (d) more than 20% larger than the structural ischaemic lesion.
ASPECTS, Alberta Stroke Program Early CT Score; CBF, cerebral blood flow; CBV, cerebral blood volume; IST-3, Third International Stroke Trial; MR, magnetic resonance; NIHSS, National Institutes of Health Stroke Scale; OCSP, Oxfordshire Community Stroke Project classification of stroke subtype; Tmax, time to peak of the residue function; w.r.t, with respect to.