Conventional CTA (R2) | Dynamic CT Angiography (R2) | |||
---|---|---|---|---|
Arterial Phase | Arteriovenous Phase | Venous Phase | ||
4-Point absolute | 0.392 | 0.439 | 0.462 | 0.374 |
5-Point relative | 0.348 | 0.349 | 0.441 | 0.321 |
20-Point relative | 0.436 | 0.421 | 0.483 | 0.368 |
Volume of hypoattenuation | 0.483 | 0.567 | 0.614 | 0.586 |
Note:—R2 indicates the adjusted coefficient of determination corrected for sex, time to follow-up imaging, additional ICA occlusion, visible early temporal branch, IV thrombolysis, and mechanical recanalization. It is an indicator of model fit; higher values indicate a better explanation of the variance of the outcome variable.
↵a Overall, dynamic CTA allows a better prediction of follow-up lesion volume than conventional CTA. Specifically, model fit was highest for reconstructions of dynamic CTA images within the arteriovenous phase. Models containing the volume of hypoattenuation performed better than models containing any of the collateral vessel grading scores.