Dichotomizing Level of Pial Collaterals on Multiphase CT Angiography for Endovascular Treatment in Acute Ischemic Stroke: Should It Be Refined for 6-Hour Time Window?

Background: Multiphase CT-Angiography (mCTA) provides time variant images of the pial vasculature supplying brain in patients with acute ischemic stroke (AIS). To develop a machine learning (ML) technique to predict infarct, penumbra and tissue perfusion from mCTA source images. Methods: 284 patients with AIS were included from the PRoveIT study. All patients had non-contrast CT, mCTA and CTP imaging at baseline and follow up MRI/NCCT imaging. Of the 284 patient images, 140 patient images were randomly selected to train and validate three ML models to predict infarct, penumbra, and perfusion parameter on CTP, respectively. The remaining unseen 144 patient images independent of the derivation cohort were used to test the derived ML models. The predicted infarct, penumbra, and perfusion volume from ML models was spatially and volumetrically compared to manually contoured follow up infarct and time-dependent Tmax thresholded volume (CTP volume), using Bland-Altman plots, concordance correlation coefficient (CCC), intra-class correlation coefficient (ICC), and Dice similarity coefficient (DSC). Results: Within the test cohort, Bland-Altman plots showed that the mean difference between the mCTA predicted infarct and follow up infarct was 21.7 mL (limit of agreement (LoA): -41.0 to 84.3mL) in the 100 patients who had acute reperfusion (mTICI 2b/2c/3), and 3.4mL (LoA: -66 to 72.9mL) in the 44 patients who did not achieve reperfusion (mTICI 0/1). Amongst reperfused subjects, CCC was 0.4 [95%CI: 0.15-0.55, P<.01] and ICC 0.42 [95% CI: 0.18-0.50, P<.01]; in non-reperfused subjects CCC was 0.52 [95%CI: 0.2-0.6, P<.001] and ICC 0.6 [95% CI: 0.37-0.76, P<.001]. No difference was observed between the mCTA and CTP predicted infarct volume for the overall test cohort (P=.67). Conclusion: Multiphase CT Angiography is able to predict infarct, penumbra and tissue perfusion, comparable to CT perfusion imaging.

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Opercular Index Score: a CT angiography-based predictor of capillary robustness and neurological outcomes in the endovascular management of acute ischemic stroke

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2016-012746 ◽

2016 ◽

Vol 9 (12) ◽

pp. 1179-1186 ◽

Cited By ~ 2

Author(s):

Alexander Copelan ◽

Monzer Chehab ◽

Waleed Brinjikji ◽

Zachary Wilseck ◽

David F Kallmes ◽

...

Keyword(s):

Ischemic Stroke ◽

Endovascular Treatment ◽

Acute Ischemic Stroke ◽

Ct Angiography ◽

Scale Score ◽

Neurological Outcome ◽

Scoring System ◽

Index Score ◽

Good Neurological Outcome ◽

Neurological Outcomes

BackgroundMany CT angiography (CTA) collateral scoring systems are either subjective or complex and time consuming.ObjectiveTo evaluate the correlation between a CTA collateral scoring system—the Opercular Index Score (OIS)—with neurological outcomes at 90 days following endovascular treatment for acute ischemic stroke (AIS) secondary to large vessel occlusion.MethodsFifty-five patients with AIS due to distal internal carotid artery, M1, or proximal M2 occlusions who underwent endovascular treatment were included. OIS was retrospectively calculated from CTA images, reconstructed from CT perfusion imaging, as the ratio of opacified M3 opercular branches in the Sylvian fissure on the unaffected side to those on the stroke side and dichotomized into favorable (OIS≤2) and poor (OIS>2). The ability of OIS to predict good neurological outcomes (modified Rankin Scale score ≤2 at 90 days) was assessed using sensitivity, specificity, and area under the curve (AUC) with receiver operating characteristic analysis.ResultsThirty-five patients had a favorable OIS and 20 patients had a poor OIS. Patients with favorable OIS had an 80.0% (n=28) rate of good neurological outcomes compared with 15.0% (n=3) of patients with a poor OIS (p<0.0001). On multivariate logistic regression analysis adjusting for baseline National Institutes of Health Stroke Scale score, OIS, and device used, favorable OIS was the only variable independently associated with good neurological outcome (OR=17.2, 95% CI 3.8 to 104.3) and demonstrated a sensitivity of 90.3% and specificity of 70.8% with an AUC of 0.822.ConclusionsOIS is a simple and practical non-invasive scoring system that can be used to predict collateral robustness and good neurological outcome among patients with AIS undergoing endovascular treatment.

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Acute Ischemic Stroke Endovascular Treatment of Patients With Large Vessel Occlusions / Akūta Cerebrāla Infarkta Endovaskulāra Ārstēšana Pacientiem ar Maģistrālo Artēriju Oklūzijām

Proceedings of the Latvian Academy of Sciences Section B Natural Exact and Applied Sciences ◽

10.1515/prolas-2015-0030 ◽

2015 ◽

Vol 69 (5) ◽

pp. 205-209

Author(s):

Arturs Balodis ◽

Maija Radziņa ◽

Evija Miglāne ◽

Ramona Valante ◽

Andrejs Millers ◽

...

Keyword(s):

Ischemic Stroke ◽

Endovascular Treatment ◽

Acute Ischemic Stroke ◽

Active Treatment ◽

Mechanical Thrombectomy ◽

Time Window ◽

Intravenous Thrombolysis ◽

University Hospital ◽

Large Artery ◽

Early Therapy

Abstract Mechanical thrombectomy as an active treatment method has recently been chosen for patients with large artery occlusions and thrombolysis beyond a time window. The aim of our study was to evaluate the results of endovascular treatment in patients with proximal vessel occlusion, compare this group with the intravenous thrombolysis group, and to identify possible criteria of active treatment. The prospective study included 81 patients hospitalised in the Pauls Stradiņš Clinical University Hospital due to acute ischemic stroke; 48 of them received mechanical thrombectomy and 33 - intravenous thrombolysis. Thrombectomy (TE) was performed using Solitaire FR stent retrievers. The NIHSS score was used for evaluation of early therapy results and mRS (modified Rankin Scale) was used for late therapy results. ASPECTS was used to define the lesion size using imaging on admission and after treatment. Median NIHSS on admission was higher in the TE group - 16 (range 12 to 19) than in the TL group - 12 (range 8 to 15) (p < 0.05). Ninety days after treatment, mRS (0-2) was seen in 67% of patients in the TE group (n = 29), and 34% of patients in the TL group (n = 9) patients (p < 0.05). Median ASPECTS was lower in TE group - 5, in comparison to the TL group - 7 (p < 0.01) Mortality frequency was higher in the TL group (p > 0.05). Frequency of symptomatic intracerebral haemorrhages was similar in the groups. Mechanical thrombectomy can achieve better late functional outcome than thrombolysis in a selected patients group.

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