Lu SS, Zhang X, Xu XQ, et al. - Seventy-three acute ischemic stroke (AIS) individuals with stroke onset between 5 and 15 h or with unclear onset time and occlusions in the M1/M2 segment of the middle cerebral artery and/or intracranial internal carotid artery underwent head non-contrast CT and CT perfusion (CTP) were enrolled by the researchers in a study in order to contrast collateral status on single-phase CT angiography (sCTA) and multiphase CT angiography (mCTA) and their powers to prognosticate a target mismatch on CTP and clinical outcome. When corresponded with mCTA, sCTA underestimated the collateral status. The ability of mCTA to prognosticate target mismatch and clinical outcome was greater than that of sCTA. An mCTA collateral score of > 3 best recognized the target mismatch and prognosticated a 90-day mRS score of 0–2. Therefore, in comparison with sCTA, the collaterals were better predicted by mCTA. An mCTA collateral score of > 3 optimized the prognostication of a target mismatch on CTP and a good clinical outcome in individuals with AIS.