Acute treatment of stroke due to spontaneous calcified cerebral emboli causing large vessel occlusion

Clinical and radiological characteristics of calcified cerebral embolism: a large case series including 242 calcified cerebral embolism

INTRODUCTION

Radiological calcified cerebral embolism (CCE) characteristics have been reported in small case series. Our aim was to describe clinical and radiological CCE characteristics in a large number of CCE and to compare characteristics between different patient groups.

METHODS

Characteristics of 79 stroke patients with CCE were analyzed retrospectively. Clinical characteristics included demographics, cardiovascular risk factors, stroke history, history of surgical/endovascular cardiovascular intervention, NIHSS on admission, stroke etiology, and presumed CCE source. Radiological characteristics included CCE diameter, density, number, involved cerebral artery and segment, and CCE distribution.

RESULTS

A total of 242 CCE were analyzed in 79 patients (median age 79, 56% men). Presumed CCE source was vascular in 54%, mixed vascular/cardiac in 32%, and undetermined in 14%. Median CCE diameter was 1.55 mm and median density 146HU. Multiple CCE were observed in 34% of patients. The middle cerebral artery was the most frequently (84%) involved artery. CCE predominantly involved distal segments. Single uniterritorial, multiple uniterritorial, and multiterritorial CCE were observed in 63%, 22%, and 15% of patients respectively. Patients with combined vascular/cardiac CCE source were older compared with patients with vascular CCE source (p = 0.0135). Correlation coefficient between CCE diameter and density was 0.69. Clinical characteristics were similar between the groups with single uniterritorial, multiple uniterritorial, and multiterritorial CCE, apart from diabetes (p = 0.0076). Concerning radiological characteristics, median diameter and density differed between these three groups (p = 0.0029 and p = 0.0035, respectively). CCE diameter was larger (p < 0.0001) and density higher (p < 0.0001) when CCE involved proximal arterial segments.

CONCLUSION

Clinical and radiological characteristics of CCE patients and CCE are variable. CCE diameter and density and presence of diabetes history differed between CCE patients with single uniterritorial, multiple uniterritorial, and multiterritorial CCE.

A 25-Year Retrospective of the Use of AI for Diagnosing Acute Stroke: Systematic Review

BACKGROUND

Stroke is a leading cause of death and disability worldwide. Rapid and accurate diagnosis is crucial for minimizing brain damage and optimizing treatment plans.

OBJECTIVE

This review aims to summarize the methods of artificial intelligence (AI)-assisted stroke diagnosis over the past 25 years, providing an overview of performance metrics and algorithm development trends. It also delves into existing issues and future prospects, intending to offer a comprehensive reference for clinical practice.

METHODS

A total of 50 representative articles published between 1999 and 2024 on using AI technology for stroke prevention and diagnosis were systematically selected and analyzed in detail.

RESULTS

AI-assisted stroke diagnosis has made significant advances in stroke lesion segmentation and classification, stroke risk prediction, and stroke prognosis. Before 2012, research mainly focused on segmentation using traditional thresholding and heuristic techniques. From 2012 to 2016, the focus shifted to machine learning (ML)-based approaches. After 2016, the emphasis moved to deep learning (DL), which brought significant improvements in accuracy. In stroke lesion segmentation and classification as well as stroke risk prediction, DL has shown superiority over ML. In stroke prognosis, both DL and ML have shown good performance.

CONCLUSIONS

Over the past 25 years, AI technology has shown promising performance in stroke diagnosis.

Successful Recanalization by Intravenous Thrombolysis in a Patient With Calcified Cerebral Emboli With Major Vessel Occlusion: A Case Report

A 69-year-old man, with a history of left superficial temporal artery-middle cerebral artery bypass due to cerebral infarction by left internal carotid artery occlusion, was hospitalized with acute right hemispatial neglect and left hemiparesis. Diffusion-weighted imaging showed a high-intensity lesion in the right insular cortex. Although there seemed to be no arterial occlusion in magnetic resonance angiography (MRA), non-contrast computed tomography (CT) on admission showed calcification in the right Sylvian fissure. As hyperacute ischemic stroke within 4.5 hours after onset, we used an intravenous recombinant tissue plasminogen activator, and his symptoms improved. Follow-up MRA revealed recanalization of the right M2 branches with distal migration of calcification. Although calcification was identified on non-contrast CT in the initial assessment, the diagnosis of middle cerebral artery occlusion was missed. Therefore, arterial occlusion should be considered when calcification is observed in the brain sulcus. This case also illustrated that intravenous thrombolysis may be effective even in calcified cerebral emboli with major vessel occlusion.

Spontaneous calcific cerebral embolization revealing a calcified rheumatic mitral stenosis: a case report

BACKGROUND

Cerebral cardiac embolism accounts for an increasing proportion of ischemic strokes and transient ischemic attacks. Calcified cerebral emboli are rare and mostly iatrogenic secondary to heart or aorta catheterization. However, spontaneous cerebral calcified embolism in the case of calcified aortic valve is very rare and there are less than 10 case reports in the literature. And a more interesting fact is that such an event, in the context of calcified mitral valve disease, has never been reported, at least to our knowledge. We are reporting a case of spontaneous calcified cerebral embolism revealing a calcified rheumatic mitral valve stenosis.

CASE PRESENTATION

We report a case of a 59 year-old Moroccan patient, with a history of rheumatic fever at the age of 14 and no history of recent cardiac intervention or aortic/carotid manipulation, who was admitted to the emergency department after a transient ischemic attack. Physical examination at admission found normal blood pressure of 124/79 mmHg and heart rate of 90 bpm. A 12-lead electrocardiogram showed an atrial fibrillation, no other anomalies. Unenhanced cerebral computed tomography imaging was performed, revealing calcified material inside both middle cerebral arteries. Transthoracic echocardiography was performed, showing severe mitral leaflets calcification with a severe mitral stenosis, probably due to rheumatic heart disease. Cervical arteries Duplex was normal. A vitamin K antagonist (acenocoumarol) was prescribed, targeting an international normalized ratio of 2-3 and mitral valve replacement surgery was performed using mechanical prosthesis. Short- and long-term health, with a 1-year follow-up, were good and the patient did not experience any stroke.

CONCLUSION

Spontaneous calcified cerebral emboli secondary to mitral valve leaflet calcifications is an extremely rare condition. Replacement of the valve is the only option to prevent recurrent emboli and outcomes are still to be determined.

Intracranial Artery Calcifications Profile as a Predictor of Recanalization Failure in Endovascular Stroke Treatment

BACKGROUND

Acute ischemic stroke with large or medium-vessel occlusion associated with intracranial artery calcification (IAC) is an infrequent phenomenon presumably associated with intracranial atherosclerotic disease. We aimed to characterize IAC and its impact on endovascular treatment outcomes.

METHODS

We performed a retrospective cross-sectional study of consecutive patients with stroke treated with thrombectomy from January 2020 to July 2021 in our institution. We described IAC findings (length, density, and location pattern) on baseline noncontrast computed tomography. Patients were divided into 3 groups: IAC related to the occlusion location (symptomatic-IAC group), unrelated to the occlusion (asymptomatic-IAC group), and absence of any IAC (non-IAC group). We analyzed the association between the IAC profile and outcomes using logistic regression models. Intracranial angioplasty and stenting were considered rescue treatments.

RESULTS

Of the 393 patients included, 26 (6.6%) patients presented a symptomatic-IAC, 77 (19.6%) patients an asymptomatic-IAC, and in 290 (73.8%) patients no IAC was observed. The rate of failed recanalization (expanded Thrombolysis in Cerebral Infarction 0-2a) before rescue treatment was higher in symptomatic-IAC (65.4%) than in asymptomatic-IAC (15.6%; P<0.001) or non-IAC (13.4%; P<0.001). Rescue procedures were more frequently performed in symptomatic-IAC (26.9%) than in asymptomatic-IAC (1.3%; P<0.001) and non-IAC (4.1%; P<0.001). After adjusting for identifiable clinical and radiological confounders, symptomatic-IAC emerged as an independent predictor of failed recanalization (odds ratio, 11.89 [95% CI, 3.94-35.91]; P<0.001), adoption of rescue procedures (odds ratio, 12.38 [95% CI, 2.22-69.09]; P=0.004), and poor functional outcome (90-day modified Rankin Scale score ≥3; odds ratio, 3.51 [95% CI, 1.02-12.00]; P=0.046).

CONCLUSIONS

The presence of IAC related to the occlusion location is associated with worse angiographic and functional outcomes. Therefore, identification of symptomatic-IAC on baseline imaging may guide optimal endovascular treatment strategy, predicting the need for intracranial stenting and angioplasty.

Thrombus Composition, Imaging, and Outcome Prediction in Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

New imaging techniques have advanced our ability to capture thrombus characteristics and burden in real time. An improved understanding of recanalization rates with thrombolysis and endovascular thrombectomy based on thrombus characteristics has spurred interest in new therapies for acute stroke.

METHODS AND RESULTS

This article reviews the biochemical, structural, and imaging characteristics of intracranial thrombi in acute ischemic stroke; the relationship between thrombus composition and response to lytic and endovascular therapies; and current and future directions for improving outcomes in patients with acute stroke based on thrombus characteristics.

DISCUSSION

Thrombus composition, size, location, and timing from stroke onset correlate with imaging findings in acute ischemic stroke and are associated with clinical outcome. Further research across multiple domains could assist in better applying our knowledge of thrombi to patient selection and individualization of acute therapies.

Endovascular treatment for calcified cerebral emboli in patients with acute ischemic stroke

OBJECTIVE

Calcified cerebral emboli (CCE) are a rare cause of acute ischemic stroke. The authors aimed to assess the association of CCE with functional outcome, successful reperfusion, and mortality. Furthermore, they aimed to assess the effectiveness of intravenous alteplase treatment and endovascular treatment (EVT), as well as the best first-line EVT approach in patients with CCE.

METHODS

The Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry is a prospective, observational multicenter registry of patients treated with EVT for acute ischemic stroke in 16 intervention hospitals in the Netherlands. The association of CCE with functional outcome, reperfusion, and mortality was evaluated using logistic regression models. Univariable comparisons were made to determine the effectiveness of intravenous alteplase treatment and the best first-line EVT approach in CCE patients.

RESULTS

The study included 3077 patients from the MR CLEAN Registry. Fifty-five patients (1.8%) had CCE. CCE were not significantly associated with worse functional outcome (adjusted common OR 0.71, 95% CI 0.44-1.15), and 29% of CCE patients achieved functional independence. An extended Thrombolysis in Cerebral Infarction score ≥ 2B was significantly less often achieved in CCE patients compared to non-CCE patients (adjusted OR [aOR] 0.52, 95% CI 0.28-0.97). Symptomatic intracranial hemorrhage occurred in 8 CCE patients (15%) vs 171 of 3022 non-CCE patients (6%; p = 0.01). The median improvement on the National Institutes of Health Stroke Scale (NIHSS) was 2 in CCE patients versus 4 in non-CCE patients (p = 0.008). CCE were not significantly associated with mortality (aOR 1.16, 95% CI 0.64-2.12). Intravenous alteplase use in CCE patients was not associated with functional outcome or reperfusion. In CCE patients with successful reperfusion, stent retrievers were more often used as the primary treatment device (p = 0.04).

CONCLUSIONS

While patients with CCE had significantly lower reperfusion rates and less improvement on the NIHSS after EVT, CCE were not significantly associated with worse functional outcome or higher mortality rates. Therefore, EVT should still be considered in this specific group of patients.

[Acute cerebral circulation impairment associated with percutaneous coronary intervention]

The article deals with generalized literature data on the current importance of the problem concerning acute cerebral ischemia occurring during percutaneous coronary interventions. Pathophysiological mechanisms of the development of acute cerebral circulation impairment are described, with their classification. Also considered are various risk factors which may cause this formidable complication, followed by describing modern methods of its surgical treatment. It is noted that the main risk factors for neurological complications appearing after revascularization of coronary arteries include age, accompanying diseases (instability of arterial pressure, diabetes mellitus, atrial fibrillation, atherorosclerotic lesions of the aorta and brachiocephalic arteries, previous stroke), as well as systolic dysfunction, leukocytosis, and a low level of cognitive function prior to operation. The development of acute cerebral circulation impairment during and after percutaneous coronary intervention is an indication for using methods of endovascular treatment. It is most appropriate to use a combination of direct percutaneous thrombectomy and a stent retriever. It is underlined in the article that removal of the thrombus form the cerebral artery is not an independent surgical procedure but rather a methodology envisaging an operation to be performed from the simplest technique to the most complicated one. As the first procedure, it is necessary to perform thrombaspiration and then, if ineffective, a second stage consisting in thrombextraction with the help of a stent retriever. Besides, in order to increase efficacy of thrombaspiration there have been worked out several techniques combining the use of direct thrombextraction and a stent retriever. Described in detail are 4 most commonly used techniques.

Value of thrombus imaging in predicting the outcomes of patients with large-vessel occlusive strokes after endovascular therapy

BACKGROUND

Acute ischemic stroke leads to serious long-term disability and high mortality, especially in patients with large-vessel occlusive strokes. Nowadays, endovascular therapy is considered as an alternative treatment for these patients. Several studies have used thrombus characteristics based on non-contrast computed tomography (NCCT) and computed tomography angiography (CTA) to predict prognosis in ischemic stroke. We conducted a systematic review to identify potential imaging predictive factors for successful recanalization and improved clinical outcome after endovascular therapy in patients with large-vessel occlusion (LVO) in anterior arterial circulation.

METHODS

The PubMed databases were searched for related studies reported between September 18, 2009, and September 18, 2019.

RESULTS

We selected 11 studies on revascularization and 12 studies on clinical outcome. Patients with thrombus of higher Hounsfield unit (HU), shorter length, higher clot burden score, and increased thrombus permeability may achieve higher recanalization and improved clinical outcome, but the matter is still under debate.

CONCLUSION

Imaging of thrombus can be used as an aseessment tool to predict the outcomes and it needs further studies in the future.

Endovascular Thrombectomy of Calcified Emboli in Acute Ischemic Stroke: A Multicenter Study

BACKGROUND AND PURPOSE

Large intracranial vessel occlusion due to calcified emboli is a rare cause of major stroke. We assessed the prevalence, imaging appearance, the effectiveness of mechanical thrombectomy, and clinical outcome of patients with large-vessel occlusion due to calcified emboli.

MATERIALS AND METHODS

We performed a retrospective analysis of clinical and procedural data of consecutive patients who underwent mechanical thrombectomy due to calcified emboli in 7 European stroke centers.

RESULTS

We screened 2969 patients, and 40 patients matched the inclusion criteria, accounting for a prevalence of 1.3%. The mean maximal density of the thrombus was 327 HU (range, 150-1200 HU), and the mean thrombus length was 9.2 mm (range, 4-20 mm). Four patients had multiple calcified emboli, and 2 patients had an embolic event during an endovascular intervention. A modified TICI score of ≥2b was achieved in 57.5% (23/40), with minimal-to-no reperfusion (modified TICI 0-1) in 32.5% (13/40) and incomplete reperfusion (modified TICI 2a) in 10% (4/40). Excellent outcome (mRS 0-1) was achieved in only 20.6%, functional independence (mRS 0-2) in 26.5% and 90-day mortality was 55.9%.

CONCLUSIONS

Acute ischemic stroke with large-vessel occlusion due to calcified emboli is a rare entity in patients undergoing thrombectomy, with considerably worse angiographic outcome and a higher mortality compared with patients with noncalcified thrombi. Good functional recovery at 3 months can still be achieved in about a quarter of patients.

Development of an in vitro model of calcified cerebral emboli in acute ischemic stroke for mechanical thrombectomy evaluation

: ​ BACKGROUND: Calcified cerebral emboli (CCEs) are a rare cause of acute ischemic stroke (AIS) and are frequently associated with poor outcomes. The presence of dense calcified material enables reliable identification of CCEs using non-contrast CT. However, recanalization rates with the available mechanical thrombectomy (MT) devices remain low. OBJECTIVE: To recreate a large vessel occlusion involving a CCE using an in vitro silicone model of the intracranial vessels and to demonstrate the feasability of this model to test different endovascular strategies to recanalize an occlusion of the M1 segment of the middle cerebral artery (MCA). : ​ METHODS: An in vitro model was developed to evaluate different endovascular treatment approaches using contemporary devices in the M1 segment of the MCA. The in vitro model consisted of a CCE analog placed in a silicone neurovascular model. Development of an appropriate CCE analog was based on characterization of human calcified tissues that represent likely sources of CCEs. Feasibility of the model was demonstrated in a small number of MT devices using four common procedural techniques. : ​ RESULTS: CCE analogs were developed with similar mechanical behavior to that of ex vivo calcified material. The in vitro model was evaluated with various MT techniques and devices to show feasibility of the model. In this limited evaluation, the most successful retrieval approach was performed with a stent retriever combined with local aspiration through a distal access catheter, and importantly, with flow arrest and dual aspiration using a balloon guide catheter. : ​ CONCLUSION: Characterization of calcified tissues, which are likely sources of CCEs, has shown that CCEs are considerably stiffer than thrombus. This highlights the need for a different in vitro AIS model for CCEs than those used for thromboemboli. Consequentially, an in vitro AIS model representative of a CCE occlusion in the M1 segment of the MCA has been developed.

Stenting of Mobile Calcified Emboli After Failed Thrombectomy in Acute Ischemic Stroke: Case Report and Literature Review

BACKGROUND

Mobile calcified emboli are a rare cause of large vessel occlusion and acute ischemic stroke and pose unique challenges to standard mechanical thrombectomy techniques. Intracranial stenting has been reported as a rescue maneuver in cases of failed mechanical thrombectomy owing to dissection or calcified atherosclerotic plaques, but its use for calcified emboli is not well described.

CASE DESCRIPTION

We present 2 cases of acute ischemic stroke caused by mobile calcified emboli. Standard mechanical thrombectomy techniques using aspiration catheters and stent-retrievers failed to remove these emboli, so intracranial stenting was successfully performed in each case, albeit after overcoming unique challenges associated with the stenting of calcified emboli. We also review the literature on intracranial stenting as a salvage therapy for failed mechanical thrombectomy.

CONCLUSIONS

Mobile calcified emboli are rare causes of acute ischemic stroke. Intracranial stenting can be used to successfully treat calcified emboli when mechanical thrombectomy has failed.

Correlation of imaging and histopathology of thrombi in acute ischemic stroke with etiology and outcome

Mechanical thrombectomy has become the stand of care for patients with large vessel occlusions, yet major improvements in thrombectomy speed, efficacy, and completeness can still be achieved. High rates of clot fragmentation and failure to remove the clot resulting in poor neurological outcomes suggest that in order to further advance the field of stroke intervention we must turn our attention towards understanding the science of clot. Accurately identifying the composition of the occlusive clot prior to intervention could significantly influence the success of the revascularization strategy used to treat them. Numerous features of thromboemboli could be studied and characterized, including quantitative histomorphometry and diagnostic imaging characteristics. Each of these features might logically predict superior thrombectomy outcomes with one device or another. This article aims to review the current literature on histopathological composition of acute ischemic stroke clots, with a particular focus on the correlation between clot composition and diagnostic imaging, stroke etiology and revascularization outcomes.

Rare Case of Floating Intimal Flap Associated with Atheromatous Carotid Plaque

BACKGROUND

A mobile carotid plaque can be detected by duplex ultrasonography and is a high-risk factor for embolic stroke.

CASE DESCRIPTION

We herein present a case involving an 80-year-old man with an asymptomatic carotid floating flap diagnosed by duplex ultrasonography and treated with carotid endarterectomy. Intraoperatively, an ulceration was found immediately proximal to the neck of the floating flap, and the shape and size of the ulceration were quite similar to those of the floating flap. In a histopathologic examination of the specimen resected by carotid endarterectomy, the plaque lacked the internal elastic lamina (IEL) at the ulceration, calcification was observed in the plaque and medial layer at the ulceration, and the floating flap consisted of the IEL accompanied by calcification, fibrin, and foamy cells.

CONCLUSIONS

Progression of the atheroma and Mönckeberg sclerosis might have affected disruption of the IEL, causing the IEL to finally peel off. A floating intimal flap accompanied by an atheroma without intraplaque hemorrhage is a rare cause of mobile plaque formation. This type of mobile plaque might not be dissolved by medical treatment alone. In such cases, surgical treatment is a suitable therapeutic choice to prevent stroke.

Successful recanalization using the Embolus Retriever with Interlinked Cage for acute stroke due to calcified cerebral emboli

Mechanical thrombectomy is a safe and effective treatment in patients with acute ischemic stroke caused by large vessel occlusions. However, in rare cases, the procedure may be challenging due to the composition of the embolus. We describe a case of a mechanical thrombectomy with the Embolus Retriever with Interlinked Cage (ERIC) device in a patient with an acute ischemic stroke due to calcified cerebral emboli in the middle cerebral artery. The procedure was done after a failed recanalization attempt with manual aspiration thrombectomy. An 82-year-old woman presented to the emergency department with a sudden onset of right-sided weakness. A computed tomographic angiography showed left middle cerebral (M1 branch) calcified emboli. After the administration of an intravenous thrombolytic agent, the patient was transferred to the angiographic suite for a mechanical thrombectomy. After failure to recanalize the vessel with manual aspiration thrombectomy, successful recanalization was achieved via mechanical thrombectomy using the ERIC device. Mechanical thrombectomy with an ERIC device can be a useful option in cases of acute ischemic stroke caused by calcified cerebral emboli.

Calcified cerebral emboli: Incidence and implications

INTRODUCTION

Calcified cerebral emboli are an increasingly recognized cause of ischaemic stroke, although recognition amongst general radiologists and clinicians can be limited. Recent literature suggests that calcified cerebral emboli are likely more common than originally thought. This study aims to define the prevalence of calcified cerebral emboli as the most likely aetiology within a cohort of confirmed cases of acute stroke, as well as compare and contrast these cases with cases of 'incidental' intracranial calcification.

METHODS

Cases of confirmed stroke between May 2014 and May 2017 were reviewed by two readers to assess for the most likely aetiology. Cases of presumed calcified cerebral embolus were categorized in to 'possible' or 'definite'. The morphology, distribution and density were analysed by two independent readers, then subsequently discussed to reach a consensus. Cases were further studied in terms of likely proximal embolic source, therapeutic interventions and clinical outcomes. A further random selection of 220 non-contrast CT head examinations were reviewed over the same time period to assess for the presence of calcification which was favoured to be 'intravascular' using the same criteria.

RESULTS

A total of 220 cases of confirmed stroke were reviewed. Thirteen of these cases were thought to be most likely secondary to calcified cerebral emboli (5.9%). Of the 13 cases, eight were considered 'definite' as previous premorbid imaging without calcification was available. Twelve patients had emboli within the anterior circulation and only one patient had an embolus in the posterior circulation. Moderate calcified atherosclerotic disease was noted within the aorta and carotid arteries of all patients. Of the 220 patients within the control group, three cases were thought to have intracranial calcification most likely to be intravascular without clinical sequelae or other supportive imaging findings of infarct.

CONCLUSION

Previously thought to be a rare complication of intra-arterial instrumentation, calcified cerebral emboli have been shown to more commonly be associated with spontaneous cerebral infarction. Whilst literature in this area remains scant, recognition and differentiation of this entity has important clinical applications regarding immediate diagnosis of stroke on non-contrast imaging, modified treatment in the acute setting as well as in regards to recurrent event prognosis and secondary prevention.

Correlation of imaging and histopathology of thrombi in acute ischemic stroke with etiology and outcome: a systematic review

BACKGROUND AND PURPOSE

Studying the imaging and histopathologic characteristics of thrombi in ischemic stroke could provide insights into stroke etiology and ideal treatment strategies. We conducted a systematic review of imaging and histologic characteristics of thrombi in acute ischemic stroke.

MATERIALS AND METHODS

We identified all studies published between January 2005 and December 2015 that reported findings related to histologic and/or imaging characteristics of thrombi in acute ischemic stroke secondary to large vessel occlusion. The five outcomes examined in this study were (1) association between histologic composition of thrombi and stroke etiology; (2) association between histologic composition of thrombi and angiographic outcomes; (3) association between thrombi imaging and histologic characteristics; (4) association between thrombi imaging characteristics and angiographic outcomes; and (5) association between imaging characteristics of thrombi and stroke etiology. A meta-analysis was performed using a random effects model.

RESULTS

There was no significant difference in the proportion of red blood cell (RBC)-rich thrombi between cardioembolic and large artery atherosclerosis etiologies (OR 1.62, 95% CI 0.1 to 28.0, p=0.63). Patients with a hyperdense artery sign had a higher odds of having RBC-rich thrombi than those without a hyperdense artery sign (OR 9.0, 95% CI 2.6 to 31.2, p<0.01). Patients with a good angiographic outcome had a mean thrombus Hounsfield unit (HU) of 55.1±3.1 compared with a mean HU of 48.4±1.9 for patients with a poor angiographic outcome (mean standard difference 6.5, 95% CI 2.7 to 10.2, p<0.001). There was no association between imaging characteristics and stroke etiology (OR 1.13, 95% CI 0.32 to 4.00, p=0.85).

CONCLUSIONS

The hyperdense artery sign is associated with RBC-rich thrombi and improved recanalization rates. However, there was no association between the histopathological characteristics of thrombi and stroke etiology and angiographic outcomes.