Aims: To evaluate pulsatility index (PI) in patients with acute ischemic stroke (AIS) who underwent endovascular thrombectomy (EVT).Methods: Patients were retrospectively recruited if their stroke were secondary to middle cerebral artery (MCA) occlusion and achieved full recanalization after EVT. Transcranial Doppler was performed within 24‐hour post‐EVT. The primary outcome was correlation between the MCA‐PI on the affected side and 3‐month functional outcome, with modified Rankin scale (mRS) ≥5 indicated extremely poor functional outcomes.Results: Totally, 170 patients were included. High MCA‐PI was positively related to the 3‐month mRS score (r = 0.288, p < 0.001). The highest quartile of the MCA‐PI was associated with a high incidence of extremely poor functional outcomes (adjusted OR, 13.33; 95% CI, 2.65–67.17; adjusted p = 0.002) after adjusting for confounding factors. The predictive capacity of the MCA‐PI for extremely poor functional outcomes was good (area under the curve, 0.755; 95% CI, 0.655–0.854; p < 0.001), and its cutoff value for predicting extremely poor outcomes was 1.04, with a sensitivity of 65.6% and specificity of 78.3%.Conclusion: The MCA‐PI on the affected side is a prognostic biomarker in patients who have undergone stroke thrombectomy. An elevated MCA‐PI may be prognostically valuable for predicting extremely poor functional outcomes.

Background: Internal carotid artery (ICA) occlusion is the major cause of ischemic stroke. The effect of collateral vessels on cerebral hemodynamics in ICA occlusion remains unclear. This study investigated the correlation between collateral vessels and the peak systolic velocity of the middle cerebral artery (MCA) in patients with ICA occlusion. Methods: The relevant collateral vessels included the anterior communicating (ACoA), posterior communicating (PCoA), and internal-external carotid (IECCA) arteries, respectively. Patients with unilateral ICA occlusion ( n = 251) underwent transcranial Doppler imaging to detect the peak systolic velocity (PSV) of the MCA and other intracranial arteries. The clinical symptoms were assessed using the National Institutes of Health Stroke Scale (NIHSS). Results: Patients with ACoA collaterals had significantly higher PSV_MCA scores and significantly lower NIHSS scores than those without ACoA collaterals ( p < 0.001). Patients without any notable collaterals and those with only IECCA had the lowest PSV_MCA and highest NIHSS scores. The PSV_MCA and NIHSS scores were negatively correlated ( r = −0.566, p < 0.001). Conclusion: Collateral circulation patency in unilateral ICA occlusion was closely associated with clinical symptoms, and patients with ACoA collaterals may have favorable outcomes. (ClinicalTrials.gov Identifier: NCT02397655)

Aims: Most studies focus on dynamic cerebral autoregulation (dCA) in the middle cerebral artery (MCA), and few studies investigated neurovascular coupling (NVC) and dCA in the posterior cerebral artery (PCA). We investigated NVC and dCA of the PCA in healthy volunteers to identify sex differences. Methods: Thirty men and 30 age‐matched women completed dCA and NCV assessments. The cerebral blood flow velocity (CBFV) and mean arterial pressure were evaluated using transcranial Doppler ultrasound and a servo‐controlled plethysmograph, respectively. The dCA parameters were analyzed using transfer function analysis. The NCV was evaluated by eyes‐open and eyes‐closed (24 s each) periodically based on voice prompts. The eyes‐open visual stimulation comprised silent reading of Beijing‐related tourist information. Results: The PCA gain was lower than that of the MCA in all frequency ranges (all p < 0.05). Phase was consistent across the cerebrovascular territories. The cerebrovascular conductance index (CVCi) and mean CBFV (MV) of the PCA were significantly higher during the eyes‐open than eyes‐closed period (CVCi: 0.50 ± 0.12 vs. 0.38 ± 0.10; MV: 42.89 ± 8.49 vs. 32.98 ± 7.25, both p < 0.001). The PCA dCA and NVC were similar between the sexes. Conclusion: We assessed two major mechanisms that maintain cerebral hemodynamic stability in healthy men and women. The visual stimulation‐evoked CBFV of the PCA was significantly increased compared to that during rest, confirming the activation of NVC. Men and women have similar functions in PCA dCA and NCV.