Characteristics of Misclassified CT Perfusion Ischemic Core in XXXX with Acute @entity385 .

@entity1 @entity63 @entity98 @entity1188 @entity385
BACKGROUND: CT perfusion (CTP) is used to estimate the extent of @entity63 core and penumbra in @entity1 with acute @entity385 . CTP reliability, however, is limited. This study aims to identify regions misclassified as @entity63 core on CTP, using @entity1188 on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as @entity1188 on follow-up. MATERIALS AND METHODS: This study included 35 @entity1 with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0). Final @entity1188 was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of @entity63 lesion agreement (core on CTP: rMTT>= 145%, aCBV<2.0 ml/100g and @entity1188 on follow-up noncontrast CT) and misclassified @entity63 core (core on CTP, not identified on follow-up noncontrast CT) regions. False discovery ratio (FDR), defined as misclassified @entity63 core volume divided by total CTP @entity63 core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and @entity98 ) were calculated for both misclassified CTP @entity63 core and @entity63 lesion agreement regions and compared using paired rank-sum tests. RESULTS: Median total CTP @entity63 core volume was 49.7ml (IQR:29.9ml-132ml); median misclassified @entity63 core volume was 30.4ml (IQR:20.9ml-77.0ml). Median FDR between @entity1 was 62% (IQR:49%-80%). Median relative mean transit time was 243% (IQR:198%-289%) and 342% (IQR:249%-432%) for misclassified and @entity63 lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43-1.79) ml/100g (P<0.01) and 1.38 (IQR:1.15-1.49) ml/100g (P<0.01) for misclassified @entity63 core and @entity63 lesion agreement, respectively. All CTP parameter values differed significantly. CONCLUSION: For all @entity1 a considerable region of the CTP @entity63 core is misclassified. CTP parameters significantly differed between @entity63 lesion agreement and misclassified CTP @entity63 core, suggesting that CTP analysis may benefit from revisions.
