Predictors of severe intracerebral hemorrhage expansion

Spot Sign in Intracerebral Hemorrhage: Critical Reappraisal and Future Clinical Implications

Hematoma expansion (HE) is a common occurrence affecting around 10% to 30% of patients with acute intracerebral hemorrhage within the initial hours from symptom onset and is the only modifiable factor associated with poor clinical outcomes. The detection of contrast extravasation on computed tomography (CT) angiography, known as the spot sign, was initially embraced as a promising radiological marker for predicting HE that could aid patient selection for acute interventions aimed at minimizing HE. However, the initial enthusiasm waned as clinical studies failed to show clear clinical benefits of hemostatic treatments when patients were selected based on the presence of this imaging marker. In this narrative review, we provide a comprehensive summary of the pathophysiology, definitions, imaging protocols, and predictive performance of the CT angiography spot sign, along with the clinical studies that have selected and treated patients based on its presence. Finally, we delve into some nuances of the spot sign that can enhance its predictive performance and help stratify HE risk with greater precision. These features include static findings observed on single-phase CT angiography (ie, number, volume, CT density, and colocalization with hypodensities), as well as dynamic findings identified on multiphase/dynamic CT angiography (ie, timing of appearance, volume increase, volume decrease for tissue dispersion, and CT density changes). In this reappraisal of the spot sign, we aim to reinvigorate research on advanced neuroimaging in intracerebral hemorrhage that could lead to a more accurate HE prediction. This could facilitate better selection for therapies aimed at preventing HE or surgical approaches to address the bleeding source.

Stepwise improvement in intracerebral haematoma expansion prediction with advanced imaging: a comprehensive comparison of existing scores

BACKGROUND

We aim to comprehensively assess and compare the predictive performance of haematoma expansion (HE) scores in a homogeneous cohort of acute intracerebral haemorrhage (ICH) patients.

METHODS

Existing scores for predicting HE in acute ICH patients were included and categorised by imaging modality: non-contrast CT (NCCT), single-phase CT angiography (sCTA) and multiphase CTA (mCTA). The predictive performance of the scores was evaluated with the c-statistic in a population of consecutive adult patients with acute ICH admitted to a tertiary care centre in Southern Alberta, Canada, between February 2012 and May 2020, investigated with a multimodal imaging protocol (NCCT, sCTA and mCTA). The primary outcome was HE (ICH volume growth ≥6 mL or ≥33%), and the secondary outcome was severe HE (ICH volume growth ≥12.5 mL or ≥66%). The DeLong test compared the best-performing scores from each imaging category.

RESULTS

16 HE scores were assessed (NCCT=8, sCTA=6 and mCTA=2) in 217 patients with a median age of 70 years (IQR=60-80), and 86 (39.6%) were females. 51 (23.5%) patients experienced HE and 35 (16.1%) had severe HE. The c-statistic for predicting HE ranged from 0.516 to 0.674 for NCCT-based scores, 0.627 to 0.725 for sCTA-based scores and 0.800 to 0.814 for mCTA-based score. The c-statistic for predicting severe HE ranged from 0.505 to 0.666 for NCCT scores, 0.651 to 0.740 for sCTA scores and 0.813 to 0.828 for mCTA scores. A statistically significant difference favouring mCTA over other imaging modalities in predicting both HE and severe HE was observed.

CONCLUSIONS

Advanced imaging demonstrated a stepwise improvement in the predictive performance of HE scores. However, no existing score achieved excellent predictive performance (c-statistics ≥0.90) in our cohort, highlighting the need for further refinement.

Co-localization of NCCT hypodensity and CTA spot sign predicts substantial intracerebral hematoma expansion: The Black-&-White sign

BACKGROUND

Existing radiological markers of hematoma expansion (HE) show modest predictive accuracy. We aim to investigate a novel radiological marker that co-localizes findings from non-contrast CT (NCCT) and CT angiography (CTA) to predict HE.

METHODS

Consecutive acute intracerebral hemorrhage patients admitted at Foothills Medical Centre in Calgary, Canada, were included. The Black-&-White sign was defined as any visually identified spot sign on CTA co-localized with a hypodensity sign on the corresponding NCCT. The primary outcome was hematoma expansion (⩾6 mL or ⩾33%). Secondary outcomes included absolute (<3, 3-6, 6-12, ⩾12 mL) and relative (0%, <25%, 25%-50%, 50%-75%, or >75%) hematoma growth scales.

RESULTS

Two-hundred patients were included, with 50 (25%) experiencing HE. Forty-four (22%) showed the spot sign, 69 (34.5%) the hypodensity sign, and 14 (7%) co-localized both as the Black-&-White sign. Those with the Black-&-White sign had higher proportions of HE (100% vs 19.4%, p < 0.001), greater absolute hematoma growth (23.37 mL (IQR = 15.41-30.27) vs 0 mL (IQR = 0-2.39), p < 0.001) and relative hematoma growth (120% (IQR = 49-192) vs 0% (0-15%), p < 0.001). The Black-&-White sign had a specificity of 100% (95%CI = 97.6%-100%), a positive predictive value of 100% (95%CI = 76.8%-100%), and an overall accuracy of 82% (95%CI = 76%-87.1%). Among the 14 patients with the Black-&-White sign, 13 showed an absolute hematoma growth ⩾12 mL, and 10 experienced a HE exceeding 75% of the initial volume. The inter-rater agreement was excellent (kappa coefficient = 0.84).

CONCLUSION

The Black-&-White sign is a robust predictor of hematoma expansion occurrence and severity, yet further validation is needed to confirm these compelling findings.

Differential Risk Factors for Hematoma Expansion in Deep and Lobar Intracerebral Hemorrhage

BACKGROUND

Understanding the risk factors for hematoma expansion (HE) in different regions of intracerebral hemorrhage (ICH) can help in the development of more accurate HE prediction tools and in implementing more effective clinical treatment interventions. This study aims to investigate the risk factors for HE in patients with lobar and deep ICH.

METHODS

A retrospective analysis was conducted on 558 cases of primary supratentorial ICH from Tongji Hospital Affiliated to Tongji University. Patients were categorized into lobar ICH and deep ICH groups. Differential analysis of ICH characteristics at different locations was performed, followed by subgroup analysis based on HE occurrence. Binary logistic regression was used to identify independent risk factors for HE in each group.

RESULTS

Among the 404 patients with ICH who underwent follow-up noncontrast computed tomography (NCCT) scans, the proportion with HE was similar in the deep ICH group (23.2%) and the lobar ICH group (22.7%). Binary logistic regression analysis revealed that fluid level (odds ratio [OR] 4.77, 95% confidence interval [CI] 1.74-13.06), admission Glasgow Coma Scale score (OR 0.87, 95% CI 0.80-0.96), and time from onset to NCCT examination (OR 0.84, 95% CI 0.75-0.94) were independently associated with HE in the deep ICH group. In the lobar ICH group, irregular shape (OR 4.96, 95% CI 1.37-18.01) and fibrinogen level (OR 0.42, 95% CI 0.21-0.86) were significant risk factors.

CONCLUSIONS

Fluid level, low admission Glasgow Coma Scale score, and shorter time from onset to NCCT are independent predictors of HE in deep ICH, whereas irregular shape and low fibrinogen levels are independent predictors of HE in lobar ICH. These findings are of great significance for elucidating the mechanisms underlying HE in different locations of ICH and for developing precise predictive models of HE.

Validation of the Black-&-White sign to predict intracerebral hematoma expansion in the multi-center PREDICT study cohort

BACKGROUND

Hematoma expansion (HE) occurs in one-fourth to one-third of patients with acute intracerebral hemorrhage (ICH) and is associated with worse outcomes. The co-localization of non-contrast computed tomography (NCCT) hypodensity and computed tomography angiography (CTA) spot sign, the so-called Black-&-White (B&W) sign, has been shown to have high predictive accuracy for HE in a single-center cohort. In this analysis, we aimed to validate the predictive accuracy of the B&W sign for HE in a multicenter cohort.

METHODS

Acute ICH patients from the multicenter, observational PREDICT study (Predicting Hematoma Growth and Outcome in Intracerebral Hemorrhage Using Contrast Bolus CT) were included. Outcomes included HE (⩾6 mL or ⩾33%) and severe HE (⩾12.5 mL or >66%). The association between B&W sign and outcomes was assessed with multivariable regression analyses adjusted for baseline factors.

RESULTS

Three hundred four patients were included, with 106 (34.9%) showing HE. The spot sign was present in 76 (25%) patients, the hypodensity sign in 119 (39.1%), and the B&W sign in 29 (9.5%). In the stratum with positive spot signs, patients with B&W signs experienced more frequent HE (79.3% vs 46.8%, p = 0.008), hematoma absolute growth (19.1 mL (interquartile range (IQR) = 6.4-40) vs 3.2 mL (IQR= 0-23.3), p = 0.018), and hematoma relative growth (92% (IQR = 16-151%) vs 24% (IQR= 0-69%), p = 0.038). There was a strong association between B&W sign and HE (adjusted odds ratio (OR) = 7.83 (95% confidence interval (CI) = 2.93-20.91)) and severe HE (adjusted OR = 5.67 (95% CI = 2.41-13.36)). The B&W sign yielded a positive predictive value of 79.3% (IQR = 61.7-90.1) for HE. Inter-rater agreement was moderate (k = 0.54).

CONCLUSION

The B&W sign is associated with an increased likelihood of HE and severe HE by approximately eightfold and fivefold, respectively.

Medial intracranial carotid artery calcifications and hematoma expansion in deep intracerebral hemorrhage

BACKGROUND

Medial intracranial carotid artery calcifications (ICAC) are associated with impaired vascular physiology, increased arterial stiffness and pulse pressure. Their presence might therefore be associated with increased risk of intracerebral hemorrhage (ICH) expansion, according to the avalanche model. We explored the association between ICAC presence and pattern and hematoma expansion (HE).

METHODS

Retrospective analysis of a monocentric, prospectively collected cohort of ICH patients admitted between June 2017 and October 2023. ICAC pattern was determined by Kockelkoren's rating scale on admission CT; medial ICAC were defined with a >6 points cutoff. A follow-up CT scan was performed within 72 h. HE was analyzed as a dichotomous (≥6 mL and/or ≥33%) and as a categorical (none/mild/moderate/severe) variable, and its predictors were explored with logistic and ordinal regression respectively, accounting for baseline volume, onset-to-CT time, and anticoagulation. All the analyses were stratified by ICH location (supratentorial deep vs lobar ICH).

RESULTS

A total of 201 patients were included (median age 78, 42% females, 59% deep ICH). Medial ICAC were significantly more common in deep ICH with HE compared with non-expanders (72% vs 49%, p = 0.03), whereas there was no association between ICAC and HE in lobar ICH (53% vs 52%, p = 0.85). This association between medial ICAC and HE in deep ICH remained significant in logistic (aOR 3.11, 95% CI [1.19-9.06], p = 0.03) and ordinal regression (acOR 2.42, 95% CI [1.19-4.99], p = 0.01).

INTERPRETATION

Ipsilateral medial ICAC are associated with higher odds of HE in deep ICH. Our findings are best interpreted as hypothesis generating, requiring prospective validation and further research to characterize the underlying biological mechanisms.

A prospective cohort study regarding usability of serum RIPK3 as a biomarker in relation to early hematoma growth and neurological outcomes after acute intracerebral hemorrhage

OBJECTIVE

The receptor-interacting protein kinase 3 (RIPK3) is a pivotal component for triggering necroptosis. We intended to investigate predictive effects of serum RIPK3 levels on early hematoma growth (EHG) and poor neurological outcome after acute intracerebral hemorrhage (ICH).

METHODS

In this prospective cohort study, 183 ICH patients and 100 controls were enrolled for measuring serum RIPK3 levels. National Institutes of Health Stroke Scale (NIHSS) and hematoma volume were recorded as the severity indicators. EHG and poststroke 6-month unfavorable outcome (modified Rankin Scale scores of 3-6) were registered as the two prognostic parameters. Multivariate analyses were implemented to discern relevance of serum RIPK3 to ICH severity and prognosis.

RESULTS

Serum RIPK3 levels of patients, which were dramatically higher than those of controls, were independently related to NIHSS scores, hematoma volume, EHG, 6-month mRS scores and unfavorable outcome. Risks of EHG and unfavorable outcome were linearly pertinent to and efficiently discriminated by RIPK3 levels under restricted cubic spline and receiver operating characteristic curve respectively. RIPK3 levels nonsignificantly interacted with age, gender, hypertension, etc. Predictive ability of RIPK3 levels resembled those of NIHSS scores and hematoma volume. The prediction models, in which serum RIPK3, NIHSS scores and hematoma volume were integrated, were visually displayed via nomograms. The models' predictive capabilities substantially surpassed that of serum RIPK3, NIHSS scores and hematoma volumes alone. The models kept stable under calibration curve.

CONCLUSION

A profound increase of serum RIPK3 levels after ICH is tightly relevant to severity, EHG and poor neurological outcomes, assuming that serum RIPK3 may emerge as a valuable prognostic predictor of ICH.