Clinical and imaging markers for the prognosis of acute ischemic stroke

Background and purpose

Significant differences in the outcomes observed in patients with acute ischemic stroke (AIS) have led to research investigations for identifying the predictors. In this retrospective study, we aimed to investigate the relationship of different clinical and imaging factors with the prognosis of AIS.

Materials and methods

All clinical and imaging metrics were compared between the good and poor prognosis groups according to the modified Rankin Scale (mRS) score at 90 days after discharge. Clinical factors included gender, age, NIHSS scores at admission, and other medical history risk factors. Imaging markers included the lesion's size and location, diffusion, and perfusion metrics of infarction core and peripheral regions, and the state of collateral circulation. Spearman's correlations were analyzed for age and imaging markers between the different groups. The Chi-square test and Cramer's V coefficient analysis were performed for gender, collateral circulation status, NIHSS score, and other stroke risk factors.

Results

A total of 89 patients with AIS were divided into the good (mRS score ≤ 2) and poor prognosis groups (mRS score ≥ 3). There were differences in NIHSS score at the admission; relative MK (rMK), relative MD (rMD), relative CBF (rCBF) of the infarction core; relative mean transit time (rMTT), relative time to peak (rTTP), and relative CBF (rCBF) of peripheral regions; and collateral circulation status between the two groups (p < 0.05). Among them, the rMK of infarction lesions had the strongest correlation with the mRS score at 90 days after discharge (r = 0.545, p < 0.001).

Conclusion

Perfusion and diffusion metrics could reflect the microstructure and blood flow characteristics of the lesion, which were the key factors for the salvage ability and prognosis of the infarction tissue. The characteristics of the infarction core and peripheral regions have different effects on the outcomes. Diffusion of infarction core has strong relations with the prognosis, whereas the time metrics (MTT, TTP) were more important for peripheral regions. MK had a more significant association with prognosis than MD. These factors were the primary markers influencing the prognosis of cerebral infarction patients.

Brain magnetic resonance imaging as predictors in pediatric anti-N-methyl-D-aspartate receptor encephalitis

OBJECTIVE

To investigate the associations between brain magnetic resonance imaging (MRI) changes and clinical profiles in children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis.

METHODS

Clinical data and brain MRI results of children diagnosed with anti-NMDAR encephalitis in Guangzhou Women and Children's Medical Center from October 2014 to June 2022 were retrospectively studied.

RESULTS

A total of 143 children (Male: female 54:89) were enrolled, with a mean onset age of 6.8 years (6.8 ± 3.1). 40.6 % (58/143) of patients had abnormal initial brain MRI. Lesions in temporal lobe (34.5 %, 20/58) and frontal lobe (25.9 %, 15/58) were relatively common. Children with abnormal initial brain MRI were prone to have fever (P = 0.023), dystonia (P = 0.037), positive MOG antibodies (P = 0.015), higher cerebrospinal fluid (CSF) white blood cell count (WBC) (P = 0.019) and to receive rituximab treatment (P = 0.037). There were no significant differences in modified Rankin Scale (mRS) scores before immunotherapy, after immunotherapy and at last follow-up between the normal initial brain MRI group and abnormal group. No initial brain MRI changes were found to be associated with relapses. Brain MRI was reviewed in 72 patients at last follow-up with a median follow-up time of 25.5 months and 48.6 % (35/72) of patients had abnormal brain MRI. The mRS score of the group with normal brain MRI at last follow-up was significantly lower than that of the abnormal group.

CONCLUSIONS

About 40.0 % of children with anti-NMDAR encephalitis had abnormal initial brain MRI. Initial brain MRI was associated with certain clinical profiles, but not with relapse and prognosis. Around half of patients had abnormal brain MRI at last follow-up and were prone to have higher mRS score.

AutoML accurately predicts endovascular mechanical thrombectomy in acute large vessel ischemic stroke

Background and objective

Automated machine learning or autoML has been widely deployed in various industries. However, their adoption in healthcare, especially in clinical settings is constrained due to a lack of clear understanding and explainability. The aim of this study is to utilize autoML for the prediction of functional outcomes in patients who underwent mechanical thrombectomy and compare it with traditional ML models with a focus on the explainability of the trained models.

Methods

A total of 156 patients of acute ischemic stroke with Large Vessel Occlusion (LVO) who underwent mechanical thrombectomy within 24 h of stroke onset were included in the study. A total of 34 treatment variables including clinical, demographic, imaging, and procedure-related data were extracted. Various conventional machine learning models such as decision tree classifier, logistic regression, random forest, kNN, and SVM as well as various autoML models such as AutoGluon, MLJAR, Auto-Sklearn, TPOT, and H2O were used to predict the modified Rankin score (mRS) at the time of patient discharge and 3 months follow-up. The sensitivity, specificity, accuracy, and AUC for traditional ML and autoML models were compared.

Results

The autoML models outperformed the traditional ML models. For the prediction of mRS at discharge, the highest testing accuracy obtained by traditional ML models for the decision tree classifier was 74.11%, whereas for autoML which was obtained through AutoGluon, it showed an accuracy of 88.23%. Similarly, for mRS at 3 months, the highest testing accuracy of traditional ML was that of the SVM classifier at 76.5%, whereas that of autoML was 85.18% obtained through MLJAR. The 24-h ASPECTS score was the most important predictor for mRS at discharge whereas for prediction of mRS at 3 months, the most important factor was mRS at discharge.

Conclusion

Automated machine learning models based on multiple treatment variables can predict the functional outcome in patients more accurately than traditional ML models. The ease of clinical coding and deployment can assist clinicians in the critical decision-making process. We have developed a demo application which can be accessed at https://mrs-score-calculator.onrender.com/.

Effect of admission serum glucose on the clinical prognosis of patients with acute ischemic stroke receiving alteplase intravenous thrombolysis

Objective: To investigate the effect of admission serum glucose on the clinical prognosis of patients with acute ischemic stroke receiving intravenous alteplase thrombolysis. Methods: Patients with acute ischemic stroke who received intravenous alteplase thrombolysis between January 2016 and December 2017 were enrolled. The clinical prognosis was assessed using the modified Rankin Scale (mRs) at 90 days after onset. Univariate and multivariate logistic regression analyses were conducted to investigate whether admission serum glucose was an independent factor in the 90-day prognosis. The predictive value of admission serum glucose for a 90-day poor prognosis was evaluated using receiver operating characteristic (ROC) curves. All patients were divided into two groups based on admission serum glucose levels: high admission serum glucose (above the cut-off value) and low admission serum glucose (below the cut-off value). The 90-day prognosis of patients with different admission serum glucose was analyzed. Results: A total of 138 patients were enrolled, including 79 males (57.24%), with a mean age of (68 ± 12) years and a median baseline National Institutes of Health Stroke Scale (NIHSS) score of 9 (6 to 13.75). There were 74 cases (53.62%) in the good prognosis group and 64 cases (46.37%) in the poor prognosis group. The results of the univariate analysis indicated that admission serum glucose in the good prognosis group was significantly lower than that in the poor prognosis group [(7.45 ± 2.31) versus (8.80 ± 3.65), p < .05]. Logistic regression analysis revealed that the admission serum glucose level was an independent risk factor for clinical prognosis at 90 days after onset (OR = 1.24, 95% CI:1.01-1.52). ROC curve analysis showed that the cutoff value of admission serum glucose for predicting poor prognosis 90 days after intravenous thrombolytic therapy with alteplase was 6.77 mmol/l AUC (area under curve) 0.623, 95%CI: 0.53-0.72, sensitivity 68.80%, specificity 52.70%. When compared with the admission serum glucose ≥6.77 mmol/l group (83 cases), the 90-day mRS scores in the admission serum glucose <6.77 mmol/l group (55 cases) were lower [3 (1 to 5) scores versus 1 (0 to 3) scores, Z = 2.89, p < .05]. Conclusions: In patients with acute ischemic stroke receiving intravenous alteplase thrombolytic therapy, a higher admission serum glucose level is an independent predictor of adverse neurological outcomes at 90 days postoperatively.

Favourable collaterals according to the Careggi Collateral Score grading system in patients treated with thrombectomy for stroke with middle cerebral artery occlusion

The ability of the current grading systems to predict optimal outcomes in stroke patients with favourable collaterals remains unexplored. We evaluated differences in the performance of grading systems between Careggi Collateral Score and ASITN/SIR collateral score to predict clinical and radiological outcomes in stroke patients with favourable collaterals who underwent thrombectomy. We included stroke patients receiving thrombectomy within 360 min after symptom onset with MCA occlusion and favourable collaterals (i.e., without poor collaterals) defined by ASITN/SIR collateral score between 2 and 4. Using ordinal regression, we estimated the association of each CCS and ASITN/SIR grade with mRS shift (0-6) at 3 months, NIHSS score (0-42) and ASPECT score (10-0) at baseline, TICI score (3-0), infarct growth, cerebral bleeding, and cerebral edema grading at 24 h by calculating the odds ratios (ORs) with two-sided 95% confidence intervals after adjustment for predefined variables. Using the best collateral grade (CCS = 4) as reference, ORs of the CCS grades were associated in the direction of unfavourable outcome on 3-month mRS shift (2.325 for CCS = 3; 5.092 for CCS = 2), in the direction of more severe baseline NIHSS score (5.434 for CCS = 3; 16.041 for CCS = 2), 24-h infarct growth (2.659 for CCS = 3; 8.288 for CCS = 4) and 24-h cerebral edema (1.057 for CCS = 3; 5.374 for CCS = 2) shift. ORs of the ASITN/SIR grades were associated in the direction of more severe baseline NIHSS score (4.332 for ASITN/SIR = 3; 16.960 for ASITN/SIR = 2) and 24-h infarct growth (2.138 for ASITN/SIR = 3; 7.490 for ASITN/SIR = 2) shift. The AUC ROC of CCS and ASITN/SIR for predicting 3-month mRS score 0-1 were 0.681 (95% CI: 0.562-0.799; p = 0.009) and 0.599 (95% CI: 0.466-0.73; p = 0.156), respectively. CCS = 4 and ASITN/SIR ≥ 3 were the optimal cut-offs to predict 3-month mRS score 0-1, respectively. CCS grading system performed better than the ASITN/SIR collateral score predicting 3-month mRS score and 24-h CED grading in stroke patients with favourable collaterals who received thrombectomy for MCA occlusion.

Clinical features and outcome of patients with autoimmune cerebellar ataxia evaluated with the Scale for the Assessment and Rating of Ataxia

BACKGROUND AND PURPOSE

This study was undertaken to assess the long-term outcome of patients with paraneoplastic and non paraneoplastic autoimmune cerebellar ataxia (ACA) using the Scale for the Assessment and Rating of Ataxia (SARA).

METHODS

Patients with subacute cerebellar ataxia admitted to our institution between September 2012 and April 2020 were prospectively recruited. Serum and/or cerebrospinal fluid was tested for neural autoantibodies by indirect immunofluorescence on mouse brain, cell-based assays, and radioimmunoassay. SARA and modified Rankin Scale (mRS) score were employed to assess patients' outcome.

RESULTS

Fifty-five patients were recruited, of whom 23 (42%) met the criteria for cerebellar ataxia of autoimmune etiology. Neural autoantibodies were detected in 22 of 23 patients (Yo-immunoglobulin G [IgG], n = 6; glutamic acid decarboxylase 65-IgG, n = 3; metabotropic glutamate receptor 1-IgG, n = 2; voltage-gated calcium channel P/Q type-IgG, n = 2; Hu-IgG, n = 1; glial fibrillary acidic protein-IgG, n = 1; IgG-binding unclassified antigens, n = 7). Thirteen patients were diagnosed with paraneoplastic cerebellar syndrome (PCS) and 10 with idiopathic ACA. All patients received immunotherapy. Median SARA score was higher in the PCS group at all time points (p = 0.0002), while it decreased significantly within the ACA group (p = 0.049) after immunotherapy. Patients with good outcome (mRS ≤ 2) had less neurological disability (SARA < 15) at disease nadir (p = 0.039) and presented less frequently with paraneoplastic neurological syndrome (p = 0.0028). The univariate linear regression model revealed a good correlation between mRS and SARA score both at disease onset (p < 0.0001) and at last follow-up (p < 0.0001). SARA score < 11 identified patients with good outcome.

CONCLUSIONS

Patients with idiopathic ACA significantly improved after immunotherapy. SARA score accurately reflects patients' clinical status and may be a suitable outcome measure for patients with ACA.

Endovascular recanalization for symptomatic subacute and chronically occluded internal carotid artery: feasibility, safety, a modified radiographic classification system, and clinical outcomes

PURPOSE

To evaluate the feasibility and safety of endovascular recanalization for symptomatic subacute and chronic internal carotid artery occlusion (ICAO); to propose a newly modified radiographic classification of ICAO that can rigorously identify suitable candidates for endovascular ICAO treatment.

METHODS

We included 42 consecutive patients who had ICAO with ischaemic symptoms refractory to medical therapy. We examined the symptomatology, complications, follow-up results and radiographic images of ICAO receiving attempted endovascular treatment. We attempted to stratify all radiographic images into categories based on morphological occlusion patterns, occlusion segments and distal ICA reconstitution on digital subtraction angiography (DSA).

RESULTS

Four types (A-D) of radiographic ICAO were identified. We redefined type B as having a tapered stump but no distal lumen. The rate of successful recanalization was 83.33% (35/42 ICAOs; type A, 18/20; type B, 7/10; type C, 10/11; type D, 0/1). The perioperative complication rate was 11.90% (5/42), including 3 asymptomatic distal embolisms, 1 symptomatic cerebral infarction and 1 asymptomatic carotid artery dissection. None of these technique-related complications led to severe neurological damage or death. Modified Rankin Scale (mRS) scores after 1-20 months of follow-up were significantly decreased in successfully revascularized patients (P < 0.001). There was no significant change in mRS scores in the 7 patients in whom recanalization failed (P > 0.05).

CONCLUSIONS

Endovascular recanalization seems to achieve technical success and clinical improvement for symptomatic subacute and chronic ICAO. Additionally, our newly modified radiographic classification of ICAO may be valuable in assessing the technical feasibility and safety of procedures in symptomatic ICAO patients.

The Impacts of Peptic Ulcer on Functional Outcomes of Ischemic Stroke

BACKGROUND AND PURPOSE

Studies have shown that peptic ulcer increased the risk of ischemic stroke and stroke recurrence. This study aimed to evaluate the impacts of peptic ulcer on functional outcomes of ischemic stroke.

METHODS

Patients with first-ever ischemic stroke were grouped as with and without history of peptic ulcer. Functional outcomes were evaluated with modified Rankin scale at 90 days after the index stroke. Favorable functional outcomes were defined as with a modified Rankin scale score of 0-2. Logistic regression was used to identify predictors for favorable functional outcomes at 90 days.

RESULTS

Among the 2577 enrolled patients with ischemic stroke, 129 (5.0%) had a history of peptic ulcer. The proportion of favorable outcome was higher in patients without peptic ulcer than those with (59.3% versus 42.6%, P < .001). Multivariate logistic analysis detected that history of peptic ulcer (odds ratio [OR] = 2.89, 95% confidence interval [CI], 1.03-8.10, P = .043), National Institute of Health Stroke Scale score (OR = 2.11, 95% CI, 1.79-2.48, P < .001), and large-artery atherosclerosis stroke subtype (OR = 4.08, 95% CI, 1.11-15.03, P = .035) decreased the likelihood of favorable outcomes.

CONCLUSIONS

Ischemic stroke patients with peptic ulcer may have an increased risk of less favorable neurological outcome at 90 days after the index stroke.

Plasma D-dimer Level, the Promising Prognostic Biomarker for the Acute Cerebral Infarction Patients

BACKGROUND

Despite being an important cause of death and functional disability, acute cerebral infarction (ACI) lacks accurate and easy tools to predict the outcome of patients beyond clinical variables such as age and stroke severity.

METHODS

To investigate if plasma D-dimer level can be used as such a prognostic biomarker for ACI, so as to better guide patients' management, we studied the association between plasma D-dimer and the functional recovery of 1173 ACI patients. The patients were divided into 2 groups according to modified Rankin Scale (mRS) scores or National Institutes of Health Stroke Scale (NIHSS) scores evaluated on the 30th day after onset.

RESULTS

We observed that plasma D-dimer level correlated significantly with the prognosis of ACI evaluated based on both mRS scores (389.68 ± 32.06 µg/L for poor prognosis versus 377.70 ± 32.68 µg/L for good prognosis, P < .001) and NIHSS scores (387.01 ± 30.60 µg/L for poor prognosis versus 375.23 ± 30.66  µg/L for good prognosis, P < .01). Logistic analysis confirmed that higher D-dimer level was a risk factor for poor prognosis (mRS: odds ratio [OR], 1.604; 95% confidence interval [CI], 1.360-1.892; P < .001; NIHSS: OR, 1.733; 95% CI, 1.461-2.056; P < .01), after adjusted for age, gender, hypertension, diabetes, smoking, and hyperlipidemia.

CONCLUSION

Our results show that plasma D-dimer level is a promising prognosis biomarker for ACI.