Computed Tomographic Angiography and Cerebral Blood Volume Can Predict Final Infarct Volume and Outcome After Recanalization

Abstract

Background and Purpose-Recanalization rates are higher in acute anterior stroke treated with stent-retrievers when compared with older techniques. However, some still have sizeable infarcts and poor outcome. This may be related to underestimation of core infarct on nonenhanced computed tomography (NECT). CT angiography (CTA) source images (CTASI) and CT perfusion may be more informative. We hypothesize that core infarct estimation with NECT, CTA, and CT perfusion predicts infarct at 24 hours and outcome after fast recanalization. Methods-Consecutive good recanalization patients with proximal anterior circulation stroke were evaluated. We assessed Alberta Stroke Program Early CT Score (ASPECTs) on NECT for subtle early infarct, hypodensity, loss of gray-white (CTASI), and low cerebral blood volume (CBV; CT perfusion). Sensitivity and specificity for predicting infarct by region were calculated. Results-Of 46 patients, 36 (78%) had successful thrombectomy. Median ASPECTS was 10 for NECT early infarct and frank hypodensity; for CBV, CTASI-ASPECTS was 8. CTASI had the highest sensitivity of 71% and specificity of 82% for 24 hours NECT infarct. There was moderate correlation and concordance between CBV/24-hour NECT (R p =0.51; R c =0.50) and CTASI/24-hour NECT (R p =0.54 and R c =0.53). Thirty-four patients (74%) had good outcomes. Median ASPECTS was higher on CTASI (8 versus 5; P=0.04) and CBV (9 versus 5; P=0.03) for patients with good versus bad outcome. There were better outcomes with increasing CTASI-ASPECTS (P=0.004) and CBV-ASPECTS (P=0.02). Conclusions-CTASI

Alberta Stroke Program Early CT Score applied to CT angiography source images is a strong predictor of futile recanalization in acute ischemic stroke

“…It has been suggested that CTA-SI could be a useful tool for estimating ischemic core since both CTA-SIASPECTS and cerebral blood volume (CBV) ASPECTS, in CT-perfusion maps, correlate with final NCCT-ASPECTS at 24 h [24]; CTA-SI-ASPECTS showing the highest sensitivity and specificity for predicting final infarct. However, CTA-SI (like other radiological markers) does not reflect all the dynamic processes of ischemic injury and may include areas of irreversible damage as well as penumbra.…”

Capabilities of perfusion ASPECTS in predicting the efficiency of intravenous thrombolytic therapy

“…Показатели изученных вариантов шкалы ASPECTS были ассоциированы с уровнем неврологического дефици-та, его динамикой и функциональным исходом острого пе-риода инсульта, что подтверждают ранее опубликованные данные о взаимосвязи перфузионных показателей с клини-ческим прогнозом [15]. Так, большая тяжесть инсульта со-пряжена со снижением баллов шкал, основанных на скоро-стных и временных параметрах, сочетании СBV и MTT, а также CBF и MTT.…”

Should CT Angiography be a Routine Component of Acute Stroke Imaging?

“…10 Computed tomography angiography source images may allow for improved patient selection for acute stroke therapeutic interventions, offering the possibility of tissue-based rather than time-based therapy. 11,12 In the recent TEMPO-1 trial, patients with minor stroke who were not considered candidates for tPA received treatment with IV TNK if they had intracranial occlusions documented on CTA, and patients treated with TNK showed significant benefit over those patients who received placebo. 4 Ongoing studies of recombinant factor VII in acute intracerebral hemorrhage are using the presence of a ''spot sign'' on CTA to select those patients most likely to benefit.…”

“…26 Would identifying these occlusions on emergent CTA, followed by thrombectomy, help these patients? While patients with low NIHSS were included in MR CLEAN (2) and EXTEND-IA (0), the median NIHSS scores (and interquartile range) of patients who were actually recruited into the endovascular arms of the studies was very high (18 [14][15][16][17][18][19][20][21][22] in MR CLEAN, 3 17 [12][13][14][15][16][17][18][19][20] in ESCAPE, 8 and 17 [13][14][15][16][17][18][19][20] for EXTEND IA 17 ). Therefore, the ideal treatment of patients with low NIHSS is unclear, and whether thrombectomy would benefit them is uncertain from the existing data.…”