Thrombus imaging characteristics within acute ischemic stroke: similarities and interdependence

Abstract

BackgroundThe effects of thrombus imaging characteristics on procedural and clinical outcomes after ischemic stroke are increasingly being studied. These thrombus characteristics – for eg, size, location, and density – are commonly analyzed as separate entities. However, it is known that some of these thrombus characteristics are strongly related. Multicollinearity can lead to unreliable prediction models. We aimed to determine the distribution, correlation and clustering of thrombus imaging characteristics based on a large dataset of anterior-circulation acute ischemic stroke patients.MethodsWe measured thrombus imaging characteristics in the MR CLEAN Registry dataset, which included occlusion location, distance from the intracranial carotid artery to the thrombus (DT), thrombus length, density, perviousness, and clot burden score (CBS). We assessed intercorrelations with Spearman’s coefficient (ρ) and grouped thrombi based on 1) occlusion location and 2) thrombus length, density and perviousness using unsupervised clustering.ResultsWe included 934 patients, of which 22% had an internal carotid artery (ICA) occlusion, 61% M1, 16% M2, and 1% another occlusion location. All thrombus characteristics were significantly correlated. Higher CBS was strongly correlated with longer DT (ρ=0.67, p<0.01), and moderately correlated with shorter thrombus length (ρ=−0.41, p<0.01). In more proximal occlusion locations, thrombi were significantly longer, denser, and less pervious. Unsupervised clustering analysis resulted in four thrombus groups; however, the cohesion within and distinction between the groups were weak.ConclusionsThrombus imaging characteristics are significantly intercorrelated – strong correlations should be considered in future predictive modeling studies. Clustering analysis showed there are no distinct thrombus archetypes – novel treatments should consider this thrombus variability.

Prognostic Value of Thrombus Volume and Interaction With First-Line Endovascular Treatment Device Choice

“…Thrombus length, density, and perviousness were measured and reported previously. 3,21 Outcome Measures and Statistical Analyses Our primary outcome was functional outcome as measured with the ordinal modified Rankin Scale (mRS) 90 days after acute ischemic stroke. Ordinal mRS values were inverted and studied with a shift analysis in line with previous studies of the MR CLEAN Registry.…”

Predictive value of clot imaging in acute ischemic stroke: A systematic review of artificial intelligence and conventional studies

“…Nevertheless, some binary target variables can be useful, such as the first pass effect in endovascular treatment, the recanalization following IV-tPA administration, the embolization, or the hemorrhage following intervention with endovascular treatment. However, thrombi population spans a large variability [89]. Prediction of thrombi biology in terms of conventional composition categorization is of limited value, when spatial heterogeneity becomes recognized as an influencing factor for thrombus response to treatment [97].…”

“…Recently, a study using the MR CLEAN Registry dataset used unsupervised clustering with the purpose of grouping thrombi based on the CT image findings according to 1) occlusion location and 2) thrombus length, density and perviousness [89] (Supplementary material Table S5). The study found that thrombus imaging characteristics form a continuum spectrum, in which a given single thrombus variable is accompanied by a large variety of other characteristics, and as such, grouping thrombi in archetypes is not adequate.…”

Thrombus Imaging Characteristics to Predict Early Recanalization in Anterior Circulation Large Vessel Occlusion Stroke

“…The data collection and thrombus imaging characteristics methods from the MR CLEAN Registry have already been described in detail previously [24,25]. The followed patient workup is in line with the one described here (our hospital is one of the MR CLEAN centers).…”

“…A chart of thrombus imaging measurements in the early-recanalized group can be found in Supplemental Figure S2. For the registry patients, such a chart is presented in [25]. ER-LVO patients had fewer ICA occlusions (1% vs. 23%, p < 0.01 after Bonferroni correction) and more M2 occlusions (32% vs. 13%, p < 0.01 after Bonferroni correction).…”