Transcranial doppler ultrasound for the diagnosis of large vessel occlusion in patients with acute ischemic stroke: A systematic review.

INTRODUCTION: Transcranial Doppler (TCD) ultrasound may enhance the swift diagnosis of large vessel occlusion (LVO) in patients with a clinical suspicion of acute ischemic stroke (AIS). This is a comprehensive review of the literature on the use and performance of TCD ultrasound in diagnosing AIS caused by LVO. PATIENTS AND METHODS: We conducted a systematic search in PubMed and Google scholar to identify studies reporting data on TCD biomarkers for LVO diagnosis and management of AIS. The main outcomes of interest were the identified TCD-derived biomarkers performances (specificity, sensitivity, predictive values) for LVO diagnosis. RESULTS: A total of 170 studies were screened, of which 7 (4.1 %) studies with a total of 2260 patients (mean age: 65.3 +/- 4.5 years, 1114 (49.3 %) females) were included in this review. Most of the studies were prospective (n=5, 71.4 %), all of the studies had an overall low risk of bias. In 6 studies (85.7 %), TCD was used at the time of hospital admission, on triage field in one study in the context of a confirmed AIS. A total of six TCD based biomarkers were described in the included articles, with high accuracies for LVO diagnosis (ranging from 85.9 % to 99.2 %). Pulsatility Index had the highest reported performances in terms of Accuracy for LVO diagnosis (ranging from 96 % to 99.2 %). Authors reported suboptimal temporal windows for data acquisition in 13-19.7 % of patients. CONCLUSION: TCD is as a promising non-invasive and cost-effective tool for LVO diagnosis, presenting opportunities to enhance stroke management.

Determinants of cerebral collateral circulation in acute ischemic stroke due to large vessel occlusion.

Introduction: Cerebral collateral circulation has a central role in ischemic stroke pathophysiology, and it is considered to correlate with infarct size, the success of reperfusion therapies, and clinical outcomes. Our aim was to study the factors influencing the development of collaterals in patients with acute ischemic stroke eligible for endovascular treatment. Materials and methods: We enrolled patients with acute ischemic stroke and large vessel occlusion of anterior circulation potentially eligible for endovascular treatment. Included patients performed multiphase CT angiography to assess collaterals that were graded by the Menon Grading Score. We investigated the associations between clinical factors and collaterals and tested independent associations with logistic (good vs. poor collaterals) and ordinal (collateral grade grouped, Menon 0-2, 3, 4-5) regression analysis adjusting for age, sex, stroke severity, and onset to CT time (OCTT). Results: We included 520 patients, the mean age was 75 (±13.6) years, 215 (41%) were men, and the median (IQR) NIHSS was 17 (11-22). Good collaterals were present in 323 (62%) patients and were associated with lower NIHSS (median 16 vs. 18; p < 0.001) and left hemisphere involvement (60% vs. 45%; p < 0.001), whereas previous stroke/TIA was more frequent in patients with poor collaterals (17 vs. 26%; p = 0.014). These results were confirmed in both logistic and ordinal regression analyses where good collaterals were associated with lower NIHSS (OR = 0.94; 95% CI = 0.91-0.96; cOR = 0.95; 95% CI = 0.92-0.97, respectively) and left hemisphere stroke (OR = 2.24; 95% CI = 1.52-3.28; cOR = 2.11; 95% CI = 1.46-3.05, respectively), while previous stroke/TIA was associated with poor collaterals (OR = 0.57; 95% CI = 0.36-0.90; cOR = 0.61; 95% CI = 0.40-0.94, respectively). Vascular risk factors, demographics, and pre-stroke treatments did not influence the collateral score. Discussion: The results of our study suggest that risk factors and demographics do not influence the development of collateral circles, except for a negative relation with previous ischemic events. We confirm an already reported observation of a possible protective effect of collaterals on tissue damage assuming NIHSS as its surrogate. The association between left hemispheric stroke and better collaterals deserves to be further explored. Further efforts are needed to identify the factors that favor the development of collaterals.

Successful Emergency Rescue Open Embolectomy for Failed Endovascular Thrombectomy in Acute Ischemic Stroke: 2-Dimensional Operative Video.

This operative video demonstrates an open surgical thrombectomy for a 61-yr-old woman with failed endovascular embolectomy in acute ischemic stroke. Good functional outcome can be achieved when this operation is timely performed within the therapeutic window. This patient has atrial fibrillation. She was admitted for sudden onset of left-sided hemiplegia and aphasia. National Institutes of Health Stroke Scale (NIHSS) was 20/42 before the operation. Computed tomography (CT) cerebral angiogram showed right internal cerebral artery (ICA) occlusion from the cervical portion. Urgent intra-arterial (IA) thrombectomy was started 2 h after symptom onset, but failed despite the use of a stentriver and a large-bore aspiration catheter together. Emergency rescue open thrombectomy was performed with right pterional craniotomy 6 h after symptom onset. Sylvian fissure was dissected to expose the supraclinoid ICA, ICA bifurcation, A1, and M1. A transverse arteriotomy was made at the ICA bifurcation and open surgical thrombectomy was performed. Reperfusion was established in 86 min after skin incision. Intraoperative indocyanine green video-angiography showed patent flow over ICA bifurcation to M1 and A1. She had a good recovery with the return of the left-sided power and was discharged home. At 2-mo postoperative assessment, she was able to walk unaided independently. The modified Barthel Index (BI) was 74/100. Her activity of daily living was independent. We must emphasize IA thrombectomy is the standard treatment, and the role of open surgery remains a potential rescue procedure. Good functional outcome can be achieved when emergency rescue open thrombectomy is performed within the therapeutic window.

Intravenous fibrinolysis plus endovascular thrombectomy versus direct endovascular thrombectomy for anterior circulation acute ischemic stroke: clinical and infarct volume results.

BACKGROUND: endovascular therapy (ET) is the standard of care for anterior circulation acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). The role of adjunctive intravenous thrombolysis (IVT) in these patients remains unclear. The present study aims to investigate whether IVT followed by ET (CoT, combined therapy) provides additional benefits over direct ET for anterior circulation AIS with LVO. METHODS: we achieved a single center retrospective study of patients with AIS caused by anterior circulation LVO, referred to our center between January 2014 and January 2017 and treated with ET. Functional recovery (modified Rankin at 3-months follow-up), recanalization rate (thrombolysis in cerebral infarction [TICI] score) and time, early follow-up brain CT scan infarct volume (EFIV) (for recanalized patients only), symptomatic intracerebral hemorrhage (sICH) and 3-month mortality were the outcomes of interests. Independent predictors of the outcomes were explored with multivariable logistic regression. RESULTS: 145 subjects were included in the study, of whom 70 underwent direct ET and 75 were treated with CoT. Functional independence at 3-months was more frequent in CoT subjects compared to patients who received direct ET (mRS score 0-1: 48.5% vs 18.6%; P < 0.001. mRS score 0-2: 67.1% vs 37.3%; P < 0.001); CoT patients had also higher first-pass success rate (62.7% vs 38.6%, P < 0.05), higher recanalization rate (84.3% vs 65.3%; P = 0.009) and, in recanalized subjects, smaller EFIV (16.4 ml vs 62.3 ml; P = 0.003). Mortality and intracranial bleeding did not differ between the two groups. In multivariable regression analysis, low baseline NIHSS score (P < 0.05), vessel recanalization (P = 0.05) and CoT (P = 0.03) were independent predictors of favorable outcome at three months. CONCLUSIONS: CoT appears more effective than ET alone for anterior circulation AIS with LVO, with similar safety profile.