Association of baseline hematoma and edema volumes with one-year outcome and long-term survival after spontaneous intracerebral hemorrhage: A community-based inception cohort study

Explainable models for predicting long-term outcomes in patients with spontaneous intracerebral haemorrhage: a retrospective cohort study

BACKGROUND AND AIM

Recently, long-term outcomes in patients with spontaneous intracerebral haemorrhage (sICH) have gained increasing attention besides acute-phase characteristics. Predictive models for long-term outcomes are valuable for risk stratification and treatment strategies. This study aimed to develop and validate an explainable model for predicting long-term recurrence and all-cause death in patients with ICH, using clinical and imaging markers of cerebral small vascular diseases from MRI.

METHOD

We retrospectively analysed data from a prospectively collected large-scale cohort of patients with acute ICH admitted to the Neurology Department of The Second Affiliated Hospital of Zhejiang University between November 2016 and April 2023. After comprehensive variable selection using least absolute shrinkage and selection operator and stepwise Cox regression, we constructed Cox proportional hazards models to predict recurrence and all-cause death. Model performance was evaluated using the concordance index, integrated Brier score and time-dependent area under the curve. Global and local interpretability were assessed using variable importance calculated as SurvSHAP(t) and SurvLIME methods for the entire training set and individual patients, respectively.

RESULTS

A total of 842 eligible patients were included. Over a median follow-up of 36 months (IQR: 12-51), 86 patients (9.1%) died, and 62 patients (6.6%) experienced recurrence of ICH. The concordance indexes for the all-cause death and recurrence models were 0.841 (95% CI 0.767 to 0.913) and 0.759 (95% CI 0.651 to 0.867), respectively, with integrated Brier scores of 0.079 and 0.063. The interpretability maps highlighted age, aetiology of ICH and low haemoglobin as key predictors of long-term death, while cortical superficial siderosis and previous haemorrhage were crucial for predicting recurrence.

CONCLUSIONS

This model demonstrates high predictive accuracy and emphasises the crucial factors in predicting long-term outcomes of patients with sICH.

Hematoma, Perihematomal Edema, and Total Lesion Predict Outcome in Patients With Intracerebral Hemorrhage

BACKGROUND

The present study aimed to evaluate the predictive abilities of hematoma volume, perihematomal edema (PHE) volume, and total lesion (hematoma + PHE) volume for poor outcome in patients with intracerebral hemorrhage (ICH).

METHODS

Patients admitted to our department between January 2015 and March 2023 were retrospectively enrolled according to the inclusion criteria and exclusion criteria. Demographic characteristics, clinical information, laboratory examinations, and imaging data were collected.

RESULTS

We included 510 patients with initial computerized tomography (CT) scan (342 [67.1%] male, median age = 62 years); 142 patients had CT scans at admission and 72 h post ICH, and 350 patients had CT scans at admission and 5-9 days after onset. Multivariate logistic regression analysis revealed that absolute hematoma, absolute PHE, and absolute total lesion at admission; absolute hematoma and absolute total lesion at 72 h after onset; absolute hematoma, absolute PHE, and absolute total lesion at 5-9 days post ICH were independently related to poor outcome (p < 0.05). Furthermore, receiver operating characteristic curves demonstrated that the total volume of hematoma and PHE at 5-9 days post ICH was a better indicator to predict poor outcome, compared to other risk factors in patients with ICH (area under curve = 0.778, 95%CI: 0.729-0.826).

CONCLUSION

The total volume of hematoma and PHE at 5-9 days after onset had the highest ability in predicting poor outcome in patients with ICH.

Perihaematomal Oedema Evolution over 2 Weeks after Spontaneous Intracerebral Haemorrhage and Association with Outcome: A Prospective Cohort Study

INTRODUCTION

We know little about the evolution of perihaematomal oedema (PHO) >24 h after ICH onset. We aimed to determine the trajectory of PHO after ICH onset and its association with outcome.

METHODS

We did a prospective cohort study using a pre-specified scanning protocol in adults with first-ever spontaneous ICH and measured absolute PHO volumes on CT head scans at ICH diagnosis and 3 ± 2, 7 ± 2, and 14 ± 2 days after ICH onset. We used the largest ICH if ICHs were multiple. The primary outcomes were (a) the trajectory of PHO after ICH onset and (b) the association between PHO (absolute volume at the time when most repeat CT head scans were obtained, and change in PHO volume at this time compared with the first CT head scan) and poor functional outcome (modified Rankin scale 3-6 at 90 days). We pre-specified multivariable logistic regression models of this association adjusting analyses for potential confounders: age, GCS, infratentorial ICH location, and intraventricular extension.

RESULTS

In 106 participants of whom 49 (46%) were female, with a median ICH volume 7 mL (interquartile range [IQR] 2-22 mL), the trajectory of median PHO volume increased from 14 mL (IQR: 7-26 mL) at diagnosis to 18 mL (IQR: 8-40 mL) at 3 ± 2 days (n = 87), 20 mL (IQR: 8-48 mL) at 7 ± 2 days (n = 93) and 21 mL (IQR: 10-54 mL) at 14 ± 2 days (n = 78) (p = <0.001). PHO volume at each time point was collinear with ICH volume at diagnosis (│r│ >0.7), but the change in PHO volume between diagnosis and each time point was not. Given collinearity, we used total lesion (i.e., ICH + PHO) volume instead of PHO volume in a logistic regression model of its association at each time point with outcome. Increasing total lesion (ICH + PHO) volume at day 7 ± 2 was associated with poor functional outcome (adjusted OR per mL 1.02, 95% CI: 1.00-1.03; p = 0.036), but the increase in PHO volume between diagnosis and day 7 ± 2 was not associated with poor functional outcome (adjusted OR per mL 1.03, 95% CI: 0.99-1.07; p = 0.132).

CONCLUSION

PHO volume increases throughout the first 2 weeks after onset of mild to moderate ICH. Total lesion (ICH + PHO) volume at day 7 ± 2 was associated with poor functional outcome, but the change in PHO volume between diagnosis and day 7 ± 2 was not. Prospective cohort studies with larger sample sizes are needed to investigate these associations and their modifiers.

Remote Ischemic Conditioning to Reduce Perihematoma Edema in Patients with Intracerebral Hemorrhage (RICOCHET): A Randomized Control Trial

Background: Early perihematomal edema (PHE) growth is associated with worse functional outcomes at 90 days. Remote Ischemic conditioning (RIC) may reduce perihematomal inflammation if applied early to patients with intracerebral hemorrhage (ICH). We hypothesize that early RIC, delivered for seven days in patients with spontaneous ICH, may reduce PHE growth. Methods: ICH patients presenting within 6 h of symptom onset and hematoma volume < 60 milliliters (mL) were randomized to an RIC + standard care or standard care (SC) group. The primary outcome measure was calculated edema extension distance (EED), with the cm assessed on day seven. Results: Sixty patients were randomized with a mean  ±  SD age of 57.5  ±  10.8 years, and twenty-two (36.7%) were female. The relative baseline median PHE were similar (RIC group 0.75 (0.5-0.9) mL vs. SC group 0.91 (0.5-1.2) mL, p  =  0.30). The median EEDs at baseline were similar (RIC group 0.58 (0.3-0.8) cm vs. SC group 0.51 (0.3-0.8) cm, p  =  0.76). There was no difference in the median day 7 EED (RIC group 1.1 (0.6-1.2) cm vs. SC group 1 (0.9-1.2) cm, p  =  0.75). Conclusions: Early RIC therapy delivered daily for seven days was feasible. However, no decrease in EED was noted with the intervention.

The association between perihaematomal oedema and functional outcome after spontaneous intracerebral haemorrhage: A systematic review and meta-analysis

PURPOSE

Perihaematomal oedema (PHO) formation has gained increasing interest as a therapeutic target after spontaneous intracerebral haemorrhage (ICH). Whether PHO contributes to poor outcome is unclear. We aimed to determine the association between PHO and outcome in patients with spontaneous ICH.

METHOD

We searched five databases up to 17 November 2021 for studies of ⩾10 adults with ICH reporting the presence of PHO and outcome. We assessed risk of bias, extracted aggregate data and used random effects meta-analysis to pool studies that reported odds ratios (OR) with 95% confidence intervals (CI). Primary outcome was poor functional outcome defined as modified Rankin Scale score of 3-6 at 3 months. Additionally, we assessed PHO growth and poor outcome at any time of follow-up. We prospectively registered the protocol in PROSPERO (CRD42020157088).

FINDINGS

We identified 12,968 articles, of which we included 27 studies (n = 9534). Eighteen studies reported an association between larger PHO volume and poor outcome, six a neutral result and three an inverse relationship. Larger absolute PHO volume was associated with poor functional outcome at 3 months (OR per mL increase of absolute PHO 1.03, 95% CI 1.00-1.06, I2 44%, four studies). Additionally, PHO growth was associated with poor outcome (OR 1.04, 95% CI 1.02-1.06, I2 0%, seven studies).

DISCUSSION

In patients with spontaneous ICH, larger PHO volume is associated with poor functional outcome at 3 months. These findings support the development and investigation of new therapeutic interventions targeting PHO formation to evaluate if reduction of PHO improves outcome after ICH.

Radiomics features from perihematomal edema for prediction of prognosis in the patients with basal ganglia hemorrhage

OBJECTIVE

We developed and validated a clinical-radiomics nomogram to predict the prognosis of basal ganglia hemorrhage patients.

METHODS

Retrospective analyses were conducted in 197 patients with basal ganglia hemorrhage (training cohort: n = 136, test cohort: n = 61) who were admitted to The First Affiliated Hospital of Shandong First Medical University (Shandong Provincial Qianfoshan Hospital) and underwent computed tomography (CT) scan. According to different prognoses, patients with basal ganglia hemorrhage were divided into two groups. Independent clinical risk factors were derived with univariate and multivariate regression analysis. Radiomics signatures were obtained using least absolute shrinkage and selection operator. A radiomics score (Rad-score) was generated by 12 radiomics signatures of perihematomal edema (PHE) from CT images that were correlated with the prognosis of basal ganglia hemorrhage patients. A clinical-radiomics nomogram was conducted by combing the Rad-score and clinical risk factors using logistic regression analysis. The prediction performance of the nomogram was tested in the training cohort and verified in the test cohort.

RESULTS

The clinical model conducted by four clinical risk factors and 12 radiomcis features were used to establish the Rad-score. The clinical-radiomics nomogram outperformed the clinical model in the training cohort [area under the curve (AUC), 0.92 vs. 0.85] and the test cohort (AUC, 0.91 vs 0.85). The clinical-radiomics nomogram showed good calibration and clinical benefit in both the training and test cohorts.

CONCLUSION

Radiomics features of PHE in patients with basal ganglia hemorrhage could contribute to the outcome prediction. The clinical-radiomics nomogram may help first-line clinicians to make individual clinical treatment decisions for patients with basal ganglia hemorrhage.

Activation of Nrf2 to Optimise Immune Responses to Intracerebral Haemorrhage

Haemorrhage into the brain parenchyma can be devastating. This manifests as spontaneous intracerebral haemorrhage (ICH) after head trauma, and in the context of vascular dementia. Randomised controlled trials have not reliably shown that haemostatic treatments aimed at limiting ICH haematoma expansion and surgical approaches to reducing haematoma volume are effective. Consequently, treatments to modulate the pathophysiological responses to ICH, which may cause secondary brain injury, are appealing. Following ICH, microglia and monocyte derived cells are recruited to the peri-haematomal environment where they phagocytose haematoma breakdown products and secrete inflammatory cytokines, which may trigger both protective and harmful responses. The transcription factor Nrf2, is activated by oxidative stress, is highly expressed by central nervous system microglia and macroglia. When active, Nrf2 induces a transcriptional programme characterised by increased expression of antioxidant, haem and heavy metal detoxification and proteostasis genes, as well as suppression of proinflammatory factors. Therefore, Nrf2 activation may facilitate adaptive-protective immune cell responses to ICH by boosting resistance to oxidative stress and heavy metal toxicity, whilst limiting harmful inflammatory signalling, which can contribute to further blood brain barrier dysfunction and cerebral oedema. In this review, we consider the responses of immune cells to ICH and how these might be modulated by Nrf2 activation. Finally, we propose potential therapeutic strategies to harness Nrf2 to improve the outcomes of patients with ICH.

Defining Delayed Perihematomal Edema Expansion in Intracerebral Hemorrhage: Segmentation, Time Course, Risk Factors and Clinical Outcome

We attempt to generate a definition of delayed perihematomal edema expansion (DPE) and analyze its time course, risk factors, and clinical outcomes. A multi-cohort data was derived from the Chinese Intracranial Hemorrhage Image Database (CICHID). A non-contrast computed tomography (NCCT) -based deep learning model was constructed for fully automated segmentation hematoma and perihematomal edema (PHE). Time course of hematoma and PHE evolution correlated to initial hematoma volume was volumetrically assessed. Predictive values for DPE were calculated through receiver operating characteristic curve analysis and were tested in an independent cohort. Logistic regression analysis was utilized to identify risk factors for DPE formation and poor outcomes. The test cohort’s Dice scores of lesion segmentation were 0.877 and 0.642 for hematoma and PHE, respectively. Overall, 1201 patients were enrolled for time-course analysis of ICH evolution. A total of 312 patients were further selected for DPE analysis. Time course analysis showed the growth peak of PHE approximately concentrates in 14 days after onset. The best cutoff for DPE to predict poor outcome was 3.34 mL of absolute PHE expansion from 4-7 days to 8-14 days (AUC=0.784, sensitivity=72.2%, specificity=81.2%), and 3.78 mL of absolute PHE expansion from 8-14 days to 15-21 days (AUC=0.682, sensitivity=59.3%, specificity=92.1%) in the derivation sample. Patients with DPE was associated with worse outcome (OR: 12.340, 95%CI: 6.378-23.873, P<0.01), and the larger initial hematoma volume (OR: 1.021, 95%CI: 1.000-1.043, P=0.049) was the significant risk factor for DPE formation. This study constructed a well-performance deep learning model for automatic segmentations of hematoma and PHE. A new definition of DPE was generated and is confirmed to be related to poor outcomes in ICH. Patients with larger initial hematoma volume have a higher risk of developing DPE formation.

European Stroke Organisation (ESO) guidelines on mobile stroke units for prehospital stroke management

The safety and efficacy of mobile stroke units (MSUs) in prehospital stroke management has recently been investigated in different clinical studies. MSUs are ambulances equipped with a CT scanner, point-of-care lab, telemedicine and are staffed with a stroke specialised medical team. This European Stroke Organisation (ESO) guideline provides an up-to-date evidence-based recommendation to assist decision-makers in their choice on using MSUs for prehospital management of suspected stroke, which includes patients with acute ischaemic stroke (AIS), intracranial haemorrhage (ICH) and stroke mimics. The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and aggregated data meta-analyses of the literature, assessed the quality of the available evidence and made specific recommendations. Expert consensus statements are provided where sufficient evidence was not available to provide recommendations based on the GRADE approach. We found moderate evidence for suggesting MSU management for patients with suspected stroke. The patient group diagnosed with AIS shows an improvement of functional outcomes at 90 days, reduced onset to treatment times and increased proportion receiving IVT within 60 min from onset. MSU management might be beneficial for patients with ICH as MSU management was associated with a higher proportion of ICH patients being primarily transported to tertiary care stroke centres. No safety concerns (all-cause mortality, proportion of stroke mimics treated with IVT, symptomatic intracranial bleeding and major extracranial bleeding) could be identified for all patients managed with a MSU compared to conventional care. We suggest MSU management to improve prehospital management of suspected stroke patients.