Ultrasound Identification of Patients at Increased Risk of Intracranial Hemorrhage After Successful Endovascular Recanalization for Acute Ischemic Stroke

Hemodynamic predictors of early neurological deterioration and clinical outcome after endovascular treatment in large artery occlusion

Objective

Half of the patients with acute large artery occlusion (LAO) have poor outcomes after endovascular treatment (EVT). Early complications such as cerebral edema and symptomatic intracranial hemorrhage (sICH) can lead to early neurological deterioration (END), which correlates with hemodynamics. This study aimed to identify the hemodynamic predictors of END and outcomes in LAO patients after EVT.

Methods

A total of 76 patients with anterior circulation LAO who underwent EVT and received transcranial Doppler (TCD) monitoring were included. Bilateral middle cerebral artery (MCA) blood flow velocities (BFVs) were measured repeatedly within 1 week. Mean flow velocities (MFV) and MFV index (ipsilateral MFV/contralateral MFV) were calculated. The primary outcome was the incidence of END within 72 h. The secondary outcome was the functional outcome at 90 days-a good outcome was defined as a modified Rankin scale (mRS) score of 0-2, while a poor outcome was defined as an mRS score of 3-6.

Results

A total of 13 patients (17.1 %) experienced END within 72 h, including 5 (38.5 %) with cerebral edema, 5 (38.5 %) with sICH, and 3 (23.0 %) with infarct progression. Multivariable logistic regression analysis showed that a higher 24 h MFV index was independently associated with END (aOR 10.5; 95 % CI 2.28-48.30, p = 0.003) and a poor 90-day outcome (aOR 5.10; 95 % CI 1.38-18.78, p = 0.014). The area under the receiver operating characteristic (ROC) curve (AUC) of the 24 h MFV index for predicting END was 0.807 (95 % CI 0.700-0.915, p = 0.0005), the sensitivity was 84.6 %, and the specificity was 66.7 %. At the 1-week TCD follow-up, patients who had poor 90-day outcomes showed significantly higher 1-week iMFV [73.5 (58.4-99.0) vs. 57.7 (45.3-76.3), p = 0.004] and MFV index [1.24 (0.98-1.57) vs.1.0 (0.87-1.15) p = 0.007]. A persistent high MFV index (PHMI) was independently associated with a poor outcome (aOR 7.77, 95 % CI 1.81-33.3, p = 0.006).

Conclusion

TCD monitoring within 24 h after EVT in LAO patients can help predict END, while dynamic follow-up within 1 week is valuable in predicting clinical outcomes.

Post-reperfusion hyperperfusion after endovascular stroke treatment: a prospective comparative study of TCD versus MRI

BACKGROUND

Increased middle cerebral artery (MCA) blood flow velocities on transcranial duplex sonography (TCD) were recently reported in individual patients after successful mechanical thrombectomy (MT) and were related to intracranial hemorrhage and poor outcome. However, the retrospective study design of prior studies precluded elucidation of the underlying pathomechanisms, and the relationship between TCD and brain parenchymal perfusion still remains to be determined.

METHODS

We prospectively investigated consecutive patients with stroke successfully recanalized by MT with TCD and MRI including contrast-enhanced perfusion sequences within 48 hours post-intervention. Increased MCA flow on TCD was defined as >30% mean blood flow velocity in the treated MCA compared with the contralateral MCA. MRI blood flow maps served to assess hyperperfusion rated by neuroradiologists blinded to TCD.

RESULTS

A total of 226 patients recanalized by MT underwent post-interventional TCD and 92 patients additionally had perfusion MRI. 85 patients (38%) had increased post-interventional MCA flow on TCD. Of these, 10 patients (12%) had an underlying focal stenosis. Increased TCD blood flow in the recanalized MCA was associated with larger infarct size, vasogenic edema, intracranial hemorrhage and poor 90-day outcome (all p≤0.005). In the subgroup for which both TCD and perfusion MRI were available, 29 patients (31%) had increased ipsilateral MCA flow velocities on TCD. Of these, 25 patients also showed parenchymal hyperperfusion on MRI (sensitivity 85%; specificity 62%). Hyperperfusion severity on MRI correlated with MCA flow velocities on TCD (rs=0.379, p<0.001).

CONCLUSIONS

TCD is a reliable bedside tool to identify post-reperfusion hyperperfusion, correlates well with perfusion MRI, and indicates risk of reperfusion injury after MT.

Early haemodynamic predictors of poor functional outcomes in patients with acute ischaemic stroke receiving endovascular therapy: a single-centre retrospective study in China

Background

Changes in cerebral haemodynamics following endovascular therapy (EVT) for large-vessel occlusion stroke may affect the outcomes of patients with acute ischaemic stroke (AIS); however, evidence supporting this belief is limited. This study aims to identify the early haemodynamic predictors of poor outcomes in patients with AIS caused by anterior circulation large-artery occlusion after undergoing EVT and to evaluate the usefulness of these indicators in predicting functional outcomes at 90 days.

Methods

This retrospective study was conducted at a single academic hospital, using prospectively collected data. We enrolled adult patients with acute anterior circulation stroke who underwent EVT. Transcranial colour-coded sonography (TCCS) examinations of the recanalised and contralateral middle cerebral artery (MCA) were performed within 12 h after undergoing EVT. Haemodynamic indicators were analysed to determine their association with poor functional outcomes (modified Rankin Scale: 3-6) 90 days after stroke. Receiver operating characteristic (ROC) curves were used to evaluate the usefulness of haemodynamic indicators in predicting functional outcomes.

Results

In total, 108 patients (median age: 66 years; 69.4% males) were enrolled in this study. Complete recanalization was achieved in 93 patients (86.1%); however, 60 patients (55.6%) had a poor 90-day outcome. The peak systolic velocity (PSV) ratio, adjusted PSV ratio, mean flow velocity (MFV) ratio, and adjusted MFV ratio of the MCA were significantly higher in patients with poor prognosis than in patients with good prognosis (p < 0.02). A multivariate logistic regression analysis showed that higher PSV ratio, adjusted PSV ratio, MFV ratio, and adjusted MFV ratio were independently associated with a poor 90-day outcomes (adjusted odds ratio: 1.11-1.48 for every 0.1 increase; p < 0.03). Furthermore, adding the adjusted MFV ratio significantly improved the prediction ability of the basic model for the 90-day poor functional outcome using the ROC analysis, the areas under ROC curves increased from 0.75 to 0.85 (p = 0.013).

Conclusions

Early TCCS examination may help in predicting poor functional outcomes at 90 days in patients with AIS who underwent EVT. Moreover, combining novel TCCS indicators (adjusted MFV ratio) with conventional parameters improved the prediction ability of the base model.

Point-of-Care Ultrasound in Neurology - Report of the EAN SPN/ESNCH/ERcNsono Neuro-POCUS Working Group

In the last decade, ultrasound examination in neurology has been undergoing a significant expansion of its modalities. In parallel, there is an increasing demand for rapid and high-quality diagnostics in various acute diseases in the prehospital setting, the emergency room, intensive care unit, and during surgical or interventional procedures. Due to the growing need for rapid answers to clinical questions, there is particular demand for diagnostic ultrasound imaging. The Neuro-POCUS working group, a joint project by the European Academy of Neurology Scientific Panel Neurosonology, the European Society of Neurosonology and Cerebral Hemodynamics, and the European Reference Centers in Neurosonology (EAN SPN/ESNCH/ERcNsono Neuro-POCUS working group), was given the task of creating a concept for point-of-care ultrasound in neurology called "Neuro-POCUS". We introduce here a new ultrasound examination concept called point-of-care ultrasound in neurology (Neuro-POCUS) designed to streamline conclusive imaging outside of the ultrasound center, directly at the bedside. The aim of this study is to encourage neurologists to add quick and disease-oriented Neuro-POCUS to accompany the patient in the critical phase as an adjunct not a substitution for computed tomography, magnetic resonance imaging, or standard comprehensive neurosonology examination. Another goal is to avoid unwanted complications during imaging-free periods, ultimately resulting in advantages for the patient.

Radiological predictors of hemorrhagic transformation after acute ischemic stroke: An evidence-based analysis

Hemorrhagic transformation (HT) is one of the most common adverse events related to acute ischemic stroke (AIS) that affects the treatment plan and clinical outcome. Identification of a sensitive radiological marker may influence the controversial thrombolytic decision in the setting of AIS and may at a minimum indicate more intensive monitoring or further prophylactic interventions. In this article we summarize possible radiological biomarkers and the role of different radiological modalities including computed tomography (CT), magnetic resonance imaging, angiography, and ultrasound in predicting HT. Different radiological indices of early ischemic changes, large ischemic lesion volume, severe blood flow restriction, blood-brain barrier disruption, poor collaterals and high blood flow velocities have been reported to be associated with higher risk of HT. The current levels of evidence of the available studies highlight the role of the different CT perfusion parameters in predicting HT. Further large standardized studies are recommended to compare the sensitivity and specificity of the different radiological markers combined and delineate the most reliable predictor.