Gray-Matter Volume Estimate Score: A Novel Semi-Automatic Method Measuring Early Ischemic Change on CT

다국어 초록 (Multilingual Abstract)

Background and Purpose We developed a novel method named Gray-matter Volume Estimate Score (GRAVES), measuring early ischemic changes on Computed Tomography (CT) semi-automatically by computer software. This study aimed to compare GRAVES and Alberta Stroke Program Early CT Score (ASPECTS) with regards to outcome prediction and inter-rater agreement.
Methods This was a retrospective cohort study. Among consecutive patients with ischemic stroke in the anterior circulation who received intra-arterial therapy (IAT), those with a readable pretreatment CT were included. Two stroke neurologists independently measured both the GRAVES and ASPECTS. GRAVES was defined as the percentage of estimated hypodense lesion in the gray matter of the ipsilateral hemisphere. Spearman correlation analysis, receiver operating characteristic (ROC) comparison test, and intra-class correlation coefficient (ICC) comparison tests were performed between GRAVES and ASPECTS.
Results Ninety-four subjects (age: 68.7±10.3; male: 54 [54.9%]) were enrolled. The mean GRAVES was 9.0±8.9 and the median ASPECTS was 8 (interquartile range, 6-9). Correlation between ASPECTS and GRAVES was good (Spearman’s rank correlation coefficient, 0.642; P<0.001). ROC comparison analysis showed that the predictive value of GRAVES for favorable outcome was not significantly different from that of ASPECTS (area under curve, 0.765 vs. 0.717; P=0.308). ICC comparison analysis revealed that inter-rater agreement of GRAVES was significantly better than that of ASPECTS (0.978 vs. 0.895; P<0.001).
Conclusions GRAVES had a good correlation with ASPECTS. GRAVES was as good as ASPECTS in predicting a favorable clinical outcome, but was better than ASPECTS regarding inter-rater agreement. GRAVES may be used to predict the outcome of IAT.

참고문헌 (Reference)

1 Barber PA, "Validity and reliability of a quantitative computed tomography score in predicting outcome of hyperacute stroke before thrombolytic therapy. ASPECTS Study Group. Alberta Stroke Programme Early CT Score" 355 : 1670-1674, 2000

2 Hill MD, "Using the baseline CT scan to select acute stroke patients for IV-IA therapy" 27 : 1612-1616, 2006

3 Kucinski T, "Unenhanced CT and acute stroke physiology" 15 : 397-407, 2005

4 Hacke W, "Thrombolysis with alteplase 3 to 4.5 hours after acute ischemic stroke" 359 : 1317-1329, 2008

5 Puetz V, "The Alberta Stroke Program Early CT Score in clinical practice: what have we learned?" 4 : 354-364, 2009

6 Lee KY, "Sequential combination of intravenous recombinant tissue plasminogen activator and intra-arterial urokinase in acute ischemic stroke" 25 : 1470-1475, 2004

7 Hill MD, "Selection of acute ischemic stroke patients for intra-arterial thrombolysis with pro-urokinase by using ASPECTS" 34 : 1925-1931, 2003

8 Hacke W, "Randomised double-blind placebo-controlled trial of thrombolytic therapy with intravenous alteplase in acute ischaemic stroke (ECASS II). Second European-Australasian Acute Stroke Study Investigators" 352 : 1245-1251, 1998

9 Goyal M, "Penumbra Pivotal Stroke Trial Investigators, Calgary Stroke Program, and the Seaman MR Research Center. Effect of baseline CT scan appearance and time to recanalization on clinical outcomes in endovascular thrombectomy of acute ischemic strokes" 42 : 93-97, 2011

10 Arakawa S, "Ischemic thresholds for gray and white matter : a diffusion and perfusion magnetic resonance study" 37 : 1211-1216, 2006

11 del Zoppo GJ, "Ischaemic damage of brain microvessels : inherent risks for thrombolytic treatment in stroke" 65 : 1-9, 1998

12 Hacke W, "Intravenous thrombolysis with recombinant tissue plasminogen activator for acute hemispheric stroke. The European Cooperative Acute Stroke Study (ECASS)" 274 : 1017-1025, 1995

13 Coutts SB, "Interobserver variation of ASPECTS in real time" 35 : e103-e105, 2004

14 Gupta AC, "Interobserver reliability of baseline noncontrast CT Alberta Stroke Program Early CT Score for intra-arterial stroke treatment selection" 33 : 1046-1049, 2012

15 Finlayson O, "Interobserver agreement of ASPECT score distribution for noncontrast CT, CT angiography, and CT perfusion in acute stroke" 44 : 234-236, 2013

16 Mak HK, "Hypodensity of >1/3 middle cerebral artery territory versus Alberta Stroke Programme Early CT Score(ASPECTS) : comparison of two methods of quantitative evaluation of early CT changes in hyperacute ischemic stroke in the community setting" 34 : 1194-1196, 2003

17 Nezu T, "Early ischemic change on CT versus diffusion-weighted imaging for patients with stroke receiving intravenous recombinant tissue-type plasminogen activator therapy : stroke acute management with urgent risk-factor assessment and improvement(SAMURAI)rt-PA registry" 42 : 2196-2200, 2011

18 Song D, "Comparison of stent retriever and intra-arterial fibrinolysis in patients with acute ischaemic stroke" 21 : 779-784, 2014

19 Hill MD, "Alberta Stroke Program early computed tomography score to select patients for endovascular treatment : Interventional Management of Stroke(IMS)-III Trial" 45 : 444-449, 2014

20 Psychogios MN, "Alberta Stroke Program Early CT Scale evaluation of multimodal computed tomography in predicting clinical outcomes of stroke patients treated with aspiration thrombectomy" 44 : 2188-2193, 2013

21 Grotta JC, "Agreement and variability in the interpretation of early CT changes in stroke patients qualifying for intravenous rtPA therapy" 30 : 1528-1533, 1999