Post-ASPECTS based on hyperdensity in NCCT immediately after thrombectomy is an ultra-early predictor of hemorrhagic transformation and prognosis

The hypoperfusion volume has a strong predictive value for hemorrhagic transformation in acute ischemic stroke patients with anterior circulation occlusion after endovascular thrombectomy

OBJECTIVE

It remains unclear whether hypoperfusion volume elevates the risk of hemorrhagic transformation (HT) after endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS). This study aims to investigate the association between hypoperfusion volume and HT after EVT.

MATERIALS AND METHODS

We retrospectively recruited AIS patients with anterior circulation occlusion after receiving EVT from January 2021 to May 2024. The pre-EVT hypoperfusion volume was assessed using computed tomography perfusion, with a hypoperfusion area defined as time-to-maximum > 6s. Multivariable analysis determined whether the hypoperfusion volume served as an independent predictor of symptomatic intracerebral hemorrhage (sICH) or intracerebral hemorrhage (ICH), and its predictive value was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

A total of 115 patients were analyzed, with 55 (47.8%) having ICH and 16 (13.9%) experiencing sICH. The median age was 67, and 28.6% were female. The median core infarct volume was 4.3 ml, and the median hypoperfusion volume was 112.8 ml. After adjusting for potential confounding factors, the hypoperfusion volume remained independently correlated with sICH (OR = 1.008, 95% CI = 1.001-1.015, P = 0.018) and ICH (OR = 1.006, 95% CI = 1.001-1.012, P = 0.033). ROC curve analysis demonstrated that the hypoperfusion volume effectively predicted sICH [(area under the curve (AUC) = 0.702] or ICH (AUC = 0.643).

CONCLUSION

The hypoperfusion volume has a strong predictive value for sICH and ICH in AIS patients with anterior circulation occlusion after EVT. This underscores the necessity of assessing the hypoperfusion volume before EVT, particularly for patients with smaller core infarct volumes in AIS.

Hypoperfusion Intensity Ratio and Hemorrhagic Transformation in Patients with Successful Recanalization after Thrombectomy

BACKGROUND AND PURPOSE

Hemorrhagic transformation remains a potentially devastating complication of acute ischemic stroke. We aimed to evaluate whether the hypoperfusion intensity ratio, a parameter derived from CT perfusion imaging, is associated with the development of hemorrhagic transformation in patients with anterior large-artery occlusion who had undergone thrombectomy.

MATERIALS AND METHODS

We retrospectively reviewed data from patients with consecutive acute ischemic strokes who had achieved successful recanalization (Thrombolysis in Cerebral Infarction score ≥2b) between January 2020 and December 2023. HIR was defined as the ratio of the volume of lesions with a time-to-maximum (Tmax) >6 seconds to those with a Tmax >10 second delay. The primary outcome, based on the European Cooperative Acute Stroke Study, was hemorrhagic transformation, diagnosed by follow-up imaging assessment in 24-hour windows, and radiologically classified as hemorrhagic infarction and parenchymal hematoma. The secondary outcome was a 3-month mRS score of ≥3.

RESULTS

Among 168 patients, 35 of 168 developed hemorrhagic transformation; 14 of 168 developed hemorrhagic infarction, and 21 of 168 developed parenchymal hematoma PH. After adjusting the latent covariates, increased hypoperfusion intensity ratio (per 0.1, adjusted OR [aOR] 1.68, 95% CI 1.26-2.25), ASPECTS (aOR 0.44, 95% CI 0.27-0.72), onset-to-puncture (aOR 1.01, 95% CI 1.00-1.02), and cardioembolism (aOR 5.6, 95% CI 1.59-19.7) were associated with hemorrhagic transformation in multivariable regression. The receiver operating characteristic curve indicated that hypoperfusion intensity ratio can predict hemorrhagic transformation accurately (area under the curve = 0.81; 95% CI, 0.738-0.882; P < .001) and predict parenchymal hematoma (area under the curve = 0.801; 95% CI, 0.727-0.875; P < .001).

CONCLUSIONS

Upon admission, hypoperfusion intensity ratio, an imaging parameter, predicted hemorrhagic transformation after reperfusion therapy in this patient population.

Post-endovascular treatment, blood-brain barrier disruption, predicts patient outcomes better than pre-treatment status

OBJECTIVES

Blood-brain barrier (BBB) disruption is an important pathological change after cerebral infarction that exacerbates brain injury. We aimed to investigate and compare the predictive utility of pre-treatment BBB permeability (BBBP) and BBBP within 1 h after endovascular treatment (EVT) for hemorrhagic transformation (HT) and 90-day prognosis.

METHODS

Patients underwent preoperative computed tomography perfusion (CTP) and non-contrast CT (NCCT) within 1 h after EVT. Preoperative BBBP was determined by the relative permeability surface area product (rPS) in the hypoperfusion area. Postoperative BBBP was determined by the post-EVT Alberta Stroke Program Early CT Score (Post-ASPECTS), which is based on brain parenchymal hyperdensity on the postoperative NCCT.

OUTCOMES

We included 100 patients. Univariate logistic regression analysis revealed correlations of preoperative rPS with HT, poor outcomes, and death. However, these correlations were not observed in multivariate logistic regression. A Post-ASPECTS ≤7 and could independently predict poor outcomes, while Post-ASPECTS ≤6 could independently predict death and HT. The baseline National Institutes of Health Stroke Scale (NIHSS) score could independently predict poor outcomes and death but not HT. A combined model using the baseline NIHSS and Post-ASPECTS scores had better predictive performance for poor outcomes and death than baseline NIHSS score alone; however, it was not superior to the predictive performance of the Post-ASPECTS score.

CONCLUSION

The preoperative rPS cannot independently predict clinical outcomes in EVT-treated patients; contrastingly, the Post-ASPECTS score could independently predict poor outcomes, death, and HT. This parameter could inform prompt postoperative treatment decisions.

Analysis of influencing factors of hemorrhagic transformation in patients with large vessel occlusion stroke after mechanical thrombectomy

OBJECTIVE

To investigate the influencing factors of hemorrhagic transformation (HT) after mechanical thrombectomy (MT) in patients with large vessel occlusion (LVO) stroke.

METHODS

From September 2018 to December 2022, 270 eligible patients with LVO who underwent MT in the First Affiliated Hospital of Nanjing medical University were selected for this retrospective study, and the patients were divided into an occurrence group and a non-occurrence group based on the immediate and 24 h postoperative head CT results. The influencing factors of postoperative HT after MT were identified using univariate and logistic regression analyses. A Nomogram was constructed using logistic variables of significance. Then, area under the ROC curve (AUC) was used to verify the predictive efficacy of the Nomogram, and decision curve analysis (DCA) was used to test the clinical validity of the Nomogram.

RESULTS

HT occurred in 60 patients (23.70%) after MT. Logistic regression analysis showed that, male (OR=2.099, 95% CI: 1.051-4.193), age ≥71.5 years (OR=3.780, 95% CI: 1.836-7.782), preoperative NIHSS score ≥16.5 (OR=2.328, 95% CI: 1.112-4.873), operation time ≥58.5 min (OR=2.930, 95% CI: 1.294-6.634), and admission blood glucose ≥7.65 mmol/L (OR=4.915, 95% CI: 2.373-10.178) were risk factors for the occurrence of HT in patients with LVO stroke after MT. Admission serum magnesium ≥0.845 mmol/L (OR=0.225, 95% CI: 0.127-0.513) was a protective factor for the occurrence of HT in the patients after MT. The ROC curve showed that the AUC of the nomogram in the training set and test set were 0.849 (95% CI: 0.787-0.910) and 0.754 (95% CI: 0.634-0.874), respectively. DCA suggested that the nomogram revealed good clinical validity in the training and test sets.

CONCLUSION

Sex, age, preoperative NIHSS score, operation time, blood glucose and serum magnesium levels at admission are influencing factors for the occurrence of HT in patients with LVO stroke after MT. The nomogram in this study has a good predictive efficiency, which can improve the diagnostic efficiency of HT after MT in patients with LVO stroke. Therefore, male patients with age ≥71.5 years, preoperative NIHSS score ≥16.5, operation time ≥58.5 min, admission blood glucose ≥7.65 mmol/L, and admission serum magnesium ≤0.845 mmol/L should raise awareness about the risk of HT after MT.

Early post-endovascular treatment contrast extravasation on dual-energy CT is associated with clinical and radiological stroke outcomes: A 10-year single-centre experience

OBJECTIVE

To determine the association between early post-endovascular treatment (EVT) contrast extravasation (CE) on dual-energy CT (DECT) and stroke outcomes.

METHODS

EVT records in 2010-2019 were screened. Exclusion criteria included the occurrence of immediate post-procedural intracranial haemorrhage (ICH). Hyperdense areas on iodine overlay maps were scored according to the Alberta Stroke Programme Early CT Score (ASPECTS), thus forming a CE-ASPECTS. Maximum parenchymal iodine concentration and maximum iodine concentration relative to the torcula were recorded. Follow-up imaging was reviewed for ICH. The primary outcome measure was the modified Rankin Scale (mRS) at 90 days.

RESULTS

Out of 651 records, 402 patients were included. CE was found in 318 patients (79%). Thirty-five patients developed ICH on follow-up imaging. Fourteen ICHs were symptomatic. Stroke progression occurred in 59 patients. Multivariable regression showed a significant association between decreasing CE-ASPECTS and the mRS at 90 days (adjusted (a)cOR: 1.10, 95% CI: 1.03-1.18), NIHSS at 24-48 h (aβ: 0.57, 95% CI: 0.29-0.84), stroke progression (aOR: 1.14, 95% CI: 1.03-1.26) and ICH (aOR: 1.21, 95% CI: 1.06-1.39), but not symptomatic ICH (aOR 1.19, 95% CI: 0.95-1.38). Iodine concentration was significantly associated with the mRS (acOR: 1.18, 95% CI: 1.06-1.32), NIHSS (aβ: 0.68, 95% CI: 0.30-1.06), ICH (aOR: 1.37, 95% CI: 1.04-1.81) and symptomatic ICH (aOR: 1.19, 95% CI: 1.02-1.38), but not stroke progression (aOR: 0.99, 95% CI: 0.86-1.15). Results of the analyses with relative iodine concentration were similar and did not improve prediction.

CONCLUSIONS

CE-ASPECTS and iodine concentration are both associated with short- and long-term stroke outcomes. CE-ASPECTS is likely a better predictor for stroke progression.