Correlation of volumetric mismatch and mismatch of Alberta Stroke Program Early CT Scores on CT perfusion maps

• Published in: Neuroradiology Vol. 51; no. 1; pp. 17 - 23
• Main Authors: Lin, Ke, Rapalino, Otto, Lee, Benjamin, Do, Kinh G., Sussmann, Amado R., Law, Meng, Pramanik, Bidyut K.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 2009; Springer; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Brain - diagnostic imaging; Brain - pathology; Brain - physiopathology; Cerebrovascular Circulation; Cognition. Intelligence; Cone-Beam Computed Tomography; Confidence Intervals; Diagnostic Neuroradiology; Female; Fundamental and applied biological sciences. Psychology; Humans; Imaging; Infarction, Middle Cerebral Artery - diagnostic imaging; Infarction, Middle Cerebral Artery - pathology; Infarction, Middle Cerebral Artery - physiopathology; Investigative techniques, diagnostic techniques (general aspects); Iohexol; Male; Medical diagnosis; Medical imaging; Medical sciences; Medicine; Medicine & Public Health; Mental imagery. Mental representation; Middle Aged; Nervous system; Neurology; Neuroradiology; Neurosciences; Neurosurgery; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Radiology; Retrospective Studies; ROC Curve; Severity of Illness Index; Stroke; Stroke - diagnostic imaging; Stroke - pathology; Stroke - physiopathology; Time Factors; Tomography; Ischemic stroke; Perfusion diffusion mismatch; Alberta Stroke Program Early CT Score; Perfusion computed tomography; Recanalization therapy; Cartography; Stroke; Nervous system diseases; Program; Radiodiagnosis; Cardiovascular disease; Cerebral disorder; Vascular disease; Treatment; Ischemia; Central nervous system disease; Computerized axial tomography; Diffusion; Cerebrovascular disease
• ISSN: 0028-3940; 1432-1920
• DOI: 10.1007/s00234-008-0454-y

Introduction We aimed to determine if volumetric mismatch between tissue at risk and tissue destined to infarct on computed tomography perfusion (CTP) can be described by the mismatch of Alberta Stroke Program Early CT Score (ASPECTS). Materials and methods Forty patients with nonlacunar middle cerebral artery infarct <6 h old who had CTP on admission were retrospectively reviewed. Two raters segmented the lesion volume on mean transit time (MTT) and cerebral blood volume (CBV) maps using thresholds of >6 s and <2.0 mL per 100 g, respectively. Two other raters assigned ASPECTS to the same MTT and CBV maps while blinded to the volumetric data. Volumetric mismatch was deemed present if ≥20%. ASPECTS mismatch (=CBV ASPECTS − MTT ASPECTS) was deemed present if ≥1. Correlation between the two types of mismatches was assessed by Spearman’s coefficient ( ρ ). ROC curve analyses were performed to determine the optimal ASPECTS mismatch cut point for volumetric mismatch ≥20%, ≥50%, ≥100%, and ≥150%. Results Median volumetric mismatch was 130% (range 10.9–2,031%) with 31 (77.5%) being ≥20%. Median ASPECTS mismatch was 2 (range 0–6) with 26 (65%) being ≥1. ASPECTS mismatch correlated strongly with volumetric mismatch with ρ  = 0.763 [95% CI 0.585–0.870], p  < 0.0001. Sensitivity and specificity for volumetric mismatch ≥20% was 83.9% [95% CI 65.5–93.5] and 100% [95% CI 65.9–100], respectively, using ASPECTS mismatch ≥1. Volumetric mismatch ≥50%, ≥100%, and ≥150% were optimally identified using ASPECTS mismatch ≥1, ≥2, and ≥2, respectively. Conclusion On CTP, ASPECTS mismatch showed strong correlation to volumetric mismatch. ASPECTS mismatch ≥1 was the optimal cut point for volumetric mismatch ≥20%.