Hyperdense artery sign on computed tomography in acute ischemic stroke

First clinical multicenter experience of the new NeVa NET 5.5 thrombectomy device

BACKGROUND

Mechanical thrombectomy for the treatment of acute ischemic stroke has undergone relevant technical improvements over recent years. However, distal emboli and incomplete reperfusion after mechanical thrombectomy are still shortcomings in the care of patients with endovascular acute ischemic stroke. The NeVa NET 5.5 thrombectomy device (Vesalio, Nashville, Tennessee, USA) is the first stent retriever featuring an integrated clot micro-filtration system, aiming to enhance first pass efficacy and reduce distal embolization. This study evaluates the safety and efficacy of the NeVa NET 5.5 thrombectomy device.

METHODS

Patients with acute anterior circulation occlusions and vessel diameters >2 mm treated with the NeVa NET 5.5 stent retriever as a first-line approach were retrospectively included in this study. Data were collected from three European comprehensive stroke centers between October 2022 and April 2024. Patient data, occlusion details, clinical outcomes, and procedure-related parameters were analyzed.

RESULTS

A total of 51 patients were included. The most common occlusion locations were the internal carotid artery terminus and intradural internal carotid artery (70.6%). The mean±SD clot length was 25.1±13.3 mm (range 4-50 mm). First pass reperfusion (eTICI 2b-3) was achieved in 78.5%, with a final reperfusion rate of eTICI 2b-3 in 98.1%. Distal embolization in new territories occurred in 3.9%. No device-related adverse events were reported, and procedure-related adverse events occurred in 7.6% of the overall included cases.

CONCLUSION

The NeVa NET 5.5 stent retriever has a high first pass reperfusion rate in large vessel occlusions of the anterior circulation, with a good safety profile and low rate of distal embolization.

Dual-Energy Computed Tomography Virtual Noncalcium Imaging of Intracranial Arteries in Acute Ischemic Stroke: Differentiation Between Acute Thrombus and Calcification

OBJECTIVE

Hyperdense artery sign (HAS) on noncontrast brain computed tomography (CT) indicates an acute thrombus within the cerebral artery. It is a valuable imaging biomarker for diagnosing large-vessel occlusion; however, its identification may be challenging with the presence of vascular calcification. Dual-energy CT virtual noncalcium (VNCa) imaging using a 3-material decomposition algorithm is helpful for differentiating between calcification and hemorrhage. This study aimed to clarify the potential of VNCa imaging for differentiating HAS from vascular calcification.

METHODS

Patients with acute ischemic stroke and large-vessel occlusion identified on MR angiography, who also underwent noncontrast dual-energy CT, were included. The 80 kV/Sn 140 kV mixed images, with a weighting factor of 0.4, were considered 120 kVp-equivalent images. Postprocessing using a 3-material decomposition algorithm to differentiate between calcium (Ca), cerebrospinal fluid, and hemorrhage was performed via a commercially available 3-dimensional workstation. A mixed image, VNCa image, color-coded Ca image, and color-coded Ca image with VNCa image overlay (color-coded Ca-overlay image) were obtained, and axial reconstruction with a 1-mm slice thickness was performed for each image type. Two experienced neuroradiologists conducted imaging evaluations in consensus.

RESULTS

Thirty-four patients (mean age, 76.0 years; 21 male and 13 female patients) were included. The mixed and VNCa images revealed an HAS (indicating an acute clot) corresponding to the large-vessel occlusion site in 30 patients. Among them, the VNCa and color-coded Ca-overlay images enabled clear differentiation between the acute thrombus and adjacent vessel wall calcification in 5 patients. Among the other 4 patients, the VNCa, Ca-overlay, and Ca images identified calcified cerebral emboli in the M1 segment in 1 patient. For the other 3 patients, no high attenuation corresponding to magnetic resonance angiography findings was observed in any of the mixed, VNCa, Ca-overlay, or Ca images.

CONCLUSIONS

VNCa and color-coded Ca-overlay images obtained via dual-energy brain CT enabled differentiation of acute thrombus from vessel wall calcification and calcified cerebral emboli in patients with acute ischemic stroke.

Comparison of radiological and clinical characteristics of COVID-19 positive and negative ischemic stroke patients undergoing revascularization: A single-centre Turkish study

OBJECTIVE

We aimed to compare the radiological and clinical characteristics of COVID-19-positive and -negative acute ischemic stroke (AIS) patients who underwent revascularization and to evaluate whether COVID-19 has an effect on revascularization and outcome in AIS patients with COVID-19 infection.

METHODS

Consecutive COVID-19 positive and negative AIS patients who underwent intravenous thrombolysis and/or endovascular therapy in our hospital between March 2020 and February 2022 were included in this study. Our study is retrospective and 23 COVID-19 positive patients and 108 COVID-19 negative patients were compared in terms of radiological and clinical characteristics.

RESULTS

Hypertension was lower in the COVID-19 positive ischemic stroke group (p=0.029). Admission NIHSS score was higher in COVID-19 positive patients (p=0.041). ASPECTS was found to be lower in COVID-19 positive ischemic stroke patients (p=0.019). The rate of hyperdense artery sign differed between groups (p=0.014) and was higher in the COVID-19 positive ischemic stroke group. The incidence of multi-vessel occlusion was found to be significantly higher in the COVID-19-positive ischemic stroke group (p=0.002). In terms of prognostic features, only the 3-month good outcome rate was statistically significantly lower in the COVID-19-positive ischemic stroke group (p=0.011).

CONCLUSION

This study found that radiologically, COVID-19 may be associated with lower ASPECTS in ischemic stroke patients receiving revascularization treatment and may predispose to multivessel occlusion and hyperdense artery sign. Clinically, COVID-19 may be associated with a more severe initial presentation and worse prognosis at 3 months in ischemic stroke patients undergoing revascularization, but may not affect long-term mortality.

Hyperdense sign as a predictor for successful recanalization and clinical outcome in acute ischemic stroke: A systematic review and meta-analysis

OBJECTIVE

To assess the prognostic values of hyperdense sign on pretreatment non-contrast head CT scan for successful recanalization (mTICI ≥2b) and 90-day good functional outcome (mRs 0-2) in patients with acute ischemic stroke undergoing mechanical thrombectomy (MT).

METHODS

Literature search on PubMed, EMBASE, and Cochrane databases from inception up to 1 November 2023 was conducted. Twelve studies which reported hyperdense sign, recanalization and clinical outcomes were included in qualitative synthesis and meta-analysis.

RESULTS

Pooled analysis demonstrated a statistically significant association between successful recanalization and hyperdense sign-positive patients who underwent MT (odd ratios (OR) = 1.47, 95% confidence interval (CI) = 1.03-2.10, p = 0.04). No statistically significant association was demonstrated between presence of hyperdense sign and good functional outcome (OR = 1.04, 95% CI: 0.72-1.49, p = 0.85) or symptomatic intracranial hemorrhage sICH (OR: 1.80, 95% CI 0.72-4.47, p = 0.21).

CONCLUSIONS

This meta-analysis demonstrated that pre-intervention hyperdense sign on CT imaging might be useful in prediction of successful recanalization after MT.

Current Management of Acute Ischemic Stroke in Africa: A Review of the Literature

BACKGROUND

Acute ischemic stroke is one of the leading causes of disability and mortality globally, with increasing incidence in Africa, as the continent is already burdened with infectious diseases. Rapid diagnosis and efficient treatment are crucial, as even a slight delay to reperfuse the brain significantly affects the recovery outcome. Neuroimaging is vital for optimal care and thrombolytic or endovascular therapy in specialised stroke care units. This review aims to discuss the burden of acute ischemic stroke in Africa and how healthcare systems have tried to reduce the incidence and improve outcomes for the disease.

METHODOLOGY

Data was collected from online databases and medical journal published on PubMed, Ovid MEDLINE, ScienceDirect and Embase bibliographical data. All articles related to acute ischemic stroke in Africa were considered.

RESULTS

The medical care for acute ischemic stroke in Africa is far from optimal with little adherence to recommended protocols. There is a lack of public awareness of the disease, imaging infrastructure, personnel, stroke care units and recovery facilities, due to poor funding. Poor knowledge of stroke signs and symptoms results in delay in treatment and poor prognosis.

CONCLUSION

We urge African leaders and private entities to invest in stroke care by building appropriate infrastructures, providing medical equipments, implementing guidelines, and sustainable follow-up systems. Telehealth is a suggested strategy to mitigate the scarcity of health personnel, and international and national efforts to increase treatment affordability should be doubled. Further extensive research on the impact of acute ischemic stroke on the African continent population is encouraged.

Usefulness of maximum intensity projection images of non-enhanced CT for detection of hyperdense middle cerebral artery sign in acute thromboembolic ischemic stroke

PURPOSE

To compare the sensitivity of the hyperdense middle cerebral artery (MCA) sign between maximum intensity projection (MIP) and conventional averaged images in patients with acute focal neurological deficits with acute thromboembolic MCA occlusion (MCA occlusion group) and patients with acute focal neurological deficits without MCA occlusion (control group).

MATERIALS AND METHODS

Initial computed tomography (CT) scans on admission were reconstructed with 5 mm thickness at every 3 mm interval for averaged and MIP images from 1 mm thickness non-contrast axial source images. Images were obtained from 30 cases each in the MCA occlusion and control groups. The CT values in the region of interests (ROIs) on the affected and unaffected sides of the MCA were compared. To compare CT values among subjects, the CT values were normalized by obtaining a ratio on the affected and unaffected sides, and the normalized CT values were analyzed using the receiver operating characteristic (ROC) curve.

RESULTS

The hyperdense MCA sign was visually detected on MIP images in 90% cases and on 5 mm averaged images in only 57% cases in the MCA occlusion group. Based on the ROC analysis of the normalized ratio on the affected and unaffected sides, area under the curve of MIP image and averaged image was 0.941 and 0.655, respectively. On MIP images, the optimal threshold of the ratio on the affected and unaffected sides was 1.152 (sensitivity: 90.0%, and specificity: 93.3%).

CONCLUSION

The hyperdense MCA sign sensitivity on 5 mm MIP images was significantly higher than that on conventional 5 mm averaged CT images. This could be useful for the early initiation of proper therapy for patients with acute focal neurological deficits.

Selecting the Appropriate First-Line Strategy Based on Hyperdense Vessel Sign in Acute Ischemic Stroke Increases First Pass Recanalization: A Tertiary Center Experience

Background:  The data pertaining to selecting an optimal first-line strategy (stent retriever [SR] vs. contact aspiration [CA]) based on noncontrast computed tomography (NCCT) in cases of acute ischemic stroke consequent to large vessel occlusion (LVO) is lacking.

Aims:  This article studies the influence of hyperdense vessel sign (HVS) in selecting optimal first-line strategy, with intention of increasing first-pass recanalization (FPR).

Methods:  Upfront approach at our center is SR technique with rescue therapy (CA) adoption consequent to three failed SR attempts to achieve successful recanalization. Data of patients with acute LVO who underwent mechanical thrombectomy from June 2017 to May 2020 was retrospectively analyzed. Patients were classified into HVS (+) and HVS (−) cohort. Rate of successful recanalization (first pass, early, and final) and efficacy of rescue therapy was assessed between the two cohorts.

Results:  Of 52 patients included, 28 and 24 were assigned to the HVS (+) and HVS (−) cohort, respectively. FPR was observed in 50% of HVS (+) and 20.9% of HVS (−) ( p  = 0.029). Early recanalization was documented in 64.2% of HVS (+) and 37.5% of HVS (−) ( p  = 0.054). Rescue therapy need was higher in patients not demonstrating HVS ( p  = 0.062). Successful recanalization was achieved with rescue therapy in 50% of HVS (−) group.

Conclusion:  A higher FPR is achievable following individualized first-pass strategy (based on NCCT appearance of clot), instead of a generalized SR first-pass approach. This CT imaging-based strategy is a step closer to achieving primary angiographic goal of FPR.

Quantitative Assessment of Hyperdense Sign Measured by Hounsfield Units is Associated with Unsuccessful Mechanical Thrombectomy

PURPOSE

Despite advancement in mechanical thrombectomy (MT) techniques, 10-30% of MT for large vessel occlusions (LVO) are unsuccessful. Current prediction models fail to address the association between patient-specific factors and reperfusion. We aimed to evaluate objective, easily reproducible, admission clinical and radiological biomarkers that predict unsuccessful MT.

METHODS

We analyzed consecutive anterior LVO MT patients at two comprehensive stroke centers. The primary outcome was unsuccessful reperfusion defined by a modified thrombolysis in cerebral infarction (mTICI) score of 0-2a. We quantitatively assessed the hyperdense vessel sign by measuring Hounsfield units (HU) on admission computed tomography (CT). Receiver operating characteristic (ROC) curves were plotted to estimate the predictive value of quantitative hyperdense middle cerebral artery (MCA) measurements (delta and ratio) and of the final model for mTICI scores. We performed multivariable logistic regression to analyze associations with outcomes.

RESULTS

Out of 348 patients 87 had unsuccessful MT. Smoking, difficult arch, vessel tortuosity, vessel calcification, diminutive vessels, truncal M1 occlusion, delta HU and HU ratio were significantly associated with unsuccessful MT in the univariate analysis. When we fitted two separate multivariate models including all significant variables and a HU measurement; delta HU <6 (odds ratio, OR = 2.07, 95% confidence intervals, CI 1.09-3.92) and HU ratio ≤1.1 (OR = 2.003, 95% CI 1.05-3.81) were independently associated with failed MT after adjustment for smoking, diminutive vessels, vessel tortuosity, and difficult arch. The area under the curve AUC<9 of the final model was 0.717.

CONCLUSION

Novel radiological biomarkers on CT, CT angiography (CTA) and digital subtraction angiography (DSA) may help identify patients refractory to standard MT and prepare interventionalists for using additional alternative methods. Quantitative assessment of HU (delta and ratio) may be important in developing objective prediction tools for unsuccessful MT.

Optimal slice thickness of brain computed tomography using a hybrid iterative reconstruction algorithm for identifying hyperdense middle cerebral artery sign of acute ischemic stroke

PURPOSE

To determine the optimal slice thickness of brain non-contrast computed tomography using a hybrid iterative reconstruction algorithm to identify hyperdense middle cerebral artery sign in patients with acute ischemic stroke.

METHODS

We retrospectively enrolled 30 patients who had presented hyperdense middle cerebral artery sign and 30 patients who showed no acute ischemic change in acute magnetic resonance imaging. Reformatted axial images at an angle of the orbitomeatal line in slice thicknesses of 0.5, 1, 3, 5, and 7 mm were generated. Optimal slice thickness for identifying hyperdense middle cerebral artery sign was evaluated by a receiver operating characteristics curve analysis and area under the curve (AUC).

RESULTS

The mean AUC value of 0.5-mm slice (0.921; 95% confidence interval (95% CI), 0.868 to 0.975) was significantly higher than those of 3-mm (0.791; 95% CI, 0.686 to 0.895; p = 0.041), 5-mm (0.691; 95% CI, 0.583 to 0.799, p < 0.001), and 7-mm (0.695; 95% CI, 0.593 to 0.797, p < 0.001) slices, whereas it was equivalent to that of 1-mm slice (0.901; 95% CI, 0.837 to 0.965, p = 0.751).

CONCLUSION

Thin slice thickness of ≤ 1 mm has a better diagnostic performance for identifying hyperdense artery sign on brain non-contrast computed tomography with a hybrid iterative reconstruction algorithm in patients with acute ischemic stroke.

Data-efficient deep learning of radiological image data for outcome prediction after endovascular treatment of patients with acute ischemic stroke

Treatment selection is becoming increasingly more important in acute ischemic stroke patient care. Clinical variables and radiological image biomarkers (old age, pre-stroke mRS, NIHSS, occlusion location, ASPECTS, among others) have an important role in treatment selection and prognosis. Radiological biomarkers require expert annotation and are subject to inter-observer variability. Recently, Deep Learning has been introduced to reproduce these radiological image biomarkers. Instead of reproducing these biomarkers, in this work, we investigated Deep Learning techniques for building models to directly predict good reperfusion after endovascular treatment (EVT) and good functional outcome using CT angiography images. These models do not require image annotation and are fast to compute. We compare the Deep Learning models to Machine Learning models using traditional radiological image biomarkers. We explored Residual Neural Network (ResNet) architectures, adapted them with Structured Receptive Fields (RFNN) and auto-encoders (AE) for network weight initialization. We further included model visualization techniques to provide insight into the network's decision-making process. We applied the methods on the MR CLEAN Registry dataset with 1301 patients. The Deep Learning models outperformed the models using traditional radiological image biomarkers in three out of four cross-validation folds for functional outcome (average AUC of 0.71) and for all folds for reperfusion (average AUC of 0.65). Model visualization showed that the arteries were relevant features for functional outcome prediction. The best results were obtained for the ResNet models with RFNN. Auto-encoder initialization often improved the results. We concluded that, in our dataset, automated image analysis with Deep Learning methods outperforms radiological image biomarkers for stroke outcome prediction and has the potential to improve treatment selection.

Brain computerized tomography reading in suspected acute ischemic stroke patients: what are essentials for medical students?

BACKGROUND

Few systematic methods prioritize the image education in medical students (MS). We hope to develop a checklist of brain computerized tomography (CT) reading in patients with suspected acute ischemic stroke (AIS) for MS and primary care (PC) physicians.

METHODS

Our pilot group generated the items indicating specific structures or signs for the checklist of brain CT reading in suspected AIS patients for MS and PC physicians. These items were used in a modified web-based Delphi process using the online software "SurveyMonkey". In total 15 panelists including neurologists, neurosurgeons, neuroradiologists, and emergency department physicians participated in the modified Delphi process. Each panelist was encouraged to express feedback, agreement or disagreement on the inclusion of each item using a 9-point Likert scale. Items with median scores of 7-9 were included in our final checklist.

RESULTS

Fifty-two items were initially provided for the first round of the Delphi process. Of these, 35 achieved general agreement of being an essential item for the MS and PC physicians. The other 17 of the 52 items in this round and another two added items suggested by the panelists were further rated in the next round. Finally, 38 items were included in the essential checklist items of brain CT reading in suspected AIS patients for MS and PC physicians.

CONCLUSIONS

We established a reference regarding the essential items of brain CT reading in suspected AIS patients. We hope this helps to minimize malpractice and a delayed diagnosis, and to improve competency-based medical education for MS and PC physicians.

Baseline Occlusion Angiographic Appearance on Mechanical Thrombectomy Suggests Underlying Etiology and Outcome

Background: Etiology of a large vessel occlusion is relevant in the management of acute ischemic stroke patients and often difficult to determine in the acute phase.

Aims: We aim to investigate whether the angiographic appearance of the occlusion is related to its etiology and outcome.

Materials and Methods: Patients without cervical carotid occlusions who underwent mechanical thrombectomy in our center from April 2015 to September 2018 were studied. Demographics, clinical and radiological variables and outcome measures, including etiological classification of stroke, were collected. Underlying intracranial atherosclerosis was estimated according to the presence of stenosis after recanalization. Patients were assigned to groups based on the appearance of the occlusion observed in the first angiogram as “tapered” or “non-tapered.” Differences were searched amongst them.

Results: 131 patients met inclusion criteria. 31 (23.6%) were “tapered” and 100 (76.3%) non-tapered. Tapered presented lower mean baseline NIHSS (10.3 ± 6.2 vs. 16.1 ± 7.2; p < 0.001), smaller acute infarct cores as CTP CBV ASPECTS (8.6 ± 1.6 vs. 7.2 ± 2.4; p = 0.003), higher proportion of instant re-occlusions (26.7 vs. 8.2%; p = 0.025), fewer complete recanalization (45.2 vs. 71.0%; p = 0.028), and more persistent occlusions (37.5 vs. 10.6%; p = 0.011) on follow up MRA. There were no differences in reperfusion rates (83.9 vs. 84.0%; p = 0.986) nor in good long term functional outcome (50.0 vs. 51.1%; p = 0.921). Intracranial atherosclerosis etiology was more common in tapered than in non-tapered occlusions (54.8 vs. 18.0%; p < 0.001).

Conclusion: The angiographic appearance of an occlusion in mechanical thrombectomy patients may determine its etiology, predict likelihood of successful recanalization, and risk of reocclusion.

"Hyperdense artery sign" in early ischemic stroke: diagnostic value of model-based reconstruction approach in comparison with standard hybrid iterative reconstruction algorithm

PURPOSE

Hyperdense artery sign is the earliest sign of ischemic stroke on non-enhanced computed tomography and it can be visible long before parenchymal changes. The aim of our study was to compare diagnostic value of model-based iterative reconstruction algorithm (IMR) with that of iterative reconstruction algorithm (iDose4) in identifying hyperdense artery sign.

METHODS

We selected 56 consecutive patients suspected for ischemic stroke, who underwent a NCCT and that demonstrated a vessel occlusion at angio-CT or developed ischemic lesion at follow-up CT. Two readers randomly analyzed images of NCCT reconstructed both with iDose4 (4 mm) and IMR (2 mm), reporting presence of hyperdense artery sign (0: no; 1: yes; 2: not sure). They rated image quality on a 4-point scale (1: unacceptable; 4: more than average) and recorded HU values of clot and of normal vessel and measured noise index, CNR and SNR.

RESULTS

Mean values of CTDI, DLP, and ED were respectively of 43 mGy, 819.7 mGy cm, and 1.72 mSv. By analyzing the IMR reconstruction, both readers were able to recognize hyperdense vessel sign in 55/56 patients, while only in 12/56 patients were identified with iDose. IMR obtained better rating of image quality (mean score for IMR 3.32 vs 2.53 for iDose), higher clot density (57.2 vs 46.7 HU), lower noise index (5 vs 2), higher CNR and SNR (respectively 4.2 vs 2 and 16.8 vs 8.5).

CONCLUSIONS

Model-based approach significantly increases sensitivity in detecting hyperdense artery sign, offering higher SNR and CNR in brain CT images in comparison with standard hybrid reconstruction algorithm.

Imaging assessment of acute ischaemic stroke: a review of radiological methods

Acute ischaemic stroke is the second largest cause of death worldwide and a cause of major physical and psychological morbidity. Current evidence based treatment includes intravenous thrombolysis (IVT) and mechanical thrombectomy (MT), both requiring careful patient selection and to be administered as quickly as possible within a limited time window from symptom onset. Imaging plays a crucial role identifying patients who may benefit from MT or IVT whilst excluding those that may be harmed. For IVT, imaging must as a minimum exclude haemorrhage, stroke mimics and provide an estimate of non-viable brain. For MT, imaging must in addition detect and characterize intra-arterial thrombus and assess the intra and extracranial arterial architecture. More advanced imaging techniques may be used to assess more accurately the volume of non-viable and potentially salvageable brain tissue. It is highly likely that further research will identify patients who would benefit from treatment beyond currently accepted time windows for IVT (4.5 h) and MT (6 h) and patients with an unknown time of symptom onset. Current evidence indicates that best outcomes are achieved when treatment is instituted as soon as possible after symptom onset. A rapid, efficient imaging pathway including interpretation is fundamental to achieving the best outcomes. This review summarizes current techniques for imaging assessment of acute stroke, highlighting strengths and limitations of each. The optimum pathway is a balance between diagnostic information, local resources, specialization and the time taken to acquire, process and interpret the data. As new evidence emerges, it is likely that the minimum required imaging data will change.

Signs in Neuroradiology: A Pictorial Review

One of the major problems radiologists face in everyday practice is to decide the correct diagnosis, or at least narrow down the list of possibilities. In this context, indicative evidences (signs) are useful to recognize pathologies, and also to narrow the list of differential diagnoses. Despite classically being described for a single disease, or a closely related family of disorders, most indications are not restricted exclusively to their traditional definition. Therefore, using signs for prognosis requires knowledge of the mechanism of their appearance, and which pathologies they are observed in. In this study, we demonstrate some of the more common and useful neuroradiologic signs with relevant images, and discuss their use in differential diagnosis.

Hyperdense Middle Cerebral Artery Sign Together with Pulmonary Thromboembolism

Background

Hyperdense middle cerebral artery sign is an appearance of the middle cerebral artery on non-contrast-enhanced computed tomography. Embolic occlusion of the pulmonary arterial system is referred to as pulmonary embolism. When pulmonary embolism coexists with a patent foramen ovale, increased pressure in the right atrium may result in widening of the foramen and consequently, cause serious conditions due to paradoxical embolus. Coexistence of hyperdense middle cerebral artery sign and pulmonary thromboembolism is very rare in the literature.

Case Report

We presented a 60-year-old female patient who had both hyperdense middle cerebral artery sign and pulmonary thromboembolism.

Conclusions

To our knowledge, togetherness of hyperdense MCA sign and pulmonary thromboembolism is extremely rare in the literature. In our case, we found both pulmonary embolism due to DVT and paradoxical embolism due to existing patent foramen ovale.

Hyperdense Artery Sign, Clot Characteristics, and Response to Intravenous Thrombolysis in Han Chinese People with Acute Large Arterial Infarction

BACKGROUND

Whether the presence of hyperdense artery sign (HAS) correlates with clot characteristics and response to intravenous thrombotic therapy (IVT) remains to be determined. Given that the existent literature was mainly from the Western nations, the current study aimed to examine the relationships among HAS, clot characteristics, and outcome of IVT in a Han Chinese sample in Taiwan. The specific objectives are (1) to correlate HAS with clot characteristics and (2) to explore relationships between HAS and effectiveness/complication of IVT.

METHODS

We enrolled 75 patients treated with IVT following acute large arterial infarctions. All patients had a baseline brain computed tomography and a follow-up image at 24 hours after thrombolysis. Correlations were explored between HAS and clot characteristics. Multivariable logistic regressions were employed to examine the relationships between HAS and response to IVT at 24 hours, including early improvement and all forms of intracerebral hemorrhage (ICH).

RESULTS

In this Han Chinese sample in Taiwan, 50.7% of the patients had HAS and 64% had early improvements following IVT. Those with HAS tended to have clots lodging at main trunks of cerebral arteries but no significant associations were found between HAS and stroke etiology. In multivariable logistic regressions, HAS predicted neither early improvement nor ICH complication.

CONCLUSIONS

Instead of clot etiology, we found that it might be clot location that correlated with HAS. HAS was not associated with early improvement or ICH complication after IVT in this Han Chinese sample. We also showed that some other patient characteristics were likely to influence outcomes of IVT, which warrant clinical attention.