Voxel-based analysis of apparent diffusion coefficient in perihaematomal oedema: associated factors and outcome predictive value for intracerebral haemorrhage

An updated systematic review and meta-analysis investigating perihematomal edema and clinical outcome after intracerebral hemorrhage

OBJECTIVES

The relationship between perihematomal edema (PHE) and intracerebral hemorrhage (ICH) outcomes is uncertain. Given newly published studies, we updated a previous systematic review and meta-analysis assessing the prognostic impact of PHE on ICH outcomes.

MATERIALS AND METHODS

Databases were searched through September 2022 using pre-defined keywords. Included studies used regression to examine the association between PHE and functional outcome (assessed by modified Rankin Scale [mRS]) and mortality. The study quality was assessed using the Newcastle-Ottawa Scale. The overall pooled effect, and secondary analyses exploring different subgroups were obtained by entering the log transformed odds ratios and their confidence intervals into a DerSimonian-Laird random effects meta-analysis.

RESULTS

Twenty-eight studies (n=8655) were included. The pooled effect size for overall outcome (mRS and mortality) was 1.05 (95% CI 1.03, 1.07; p<0.00). In secondary analyses, PHE volume and growth effect sizes were 1.03 (CI 1.01, 1.05) and 1.12 (CI 1.06, 1.19), respectively. Results of subgroup analyses assessing absolute PHE volume and growth at different time points were: baseline volume 1.02 (CI 0.98, 1.06), 72-hour volume 1.07 (CI 0.99, 1.16), growth at 24 hours 1.30 (CI 0.96, 1.74) and growth at 72 hours 1.10 (CI 1.04, 1.17). Heterogeneity across studies was substantial.

CONCLUSIONS

This meta-analysis indicates that PHE growth, especially within the first 24 hours after ictus, has a stronger impact on functional outcome and mortality than PHE volume. Definitive conclusions are limited by the large variability of PHE measures, heterogeneity, and different evaluation time points between studies.

Cytotoxic Edema and Adverse Clinical Outcomes in Patients with Intracerebral Hemorrhage

BACKGROUND

Cytotoxic edema (CE) is an important form of perihematomal edema (PHE), which is a surrogate marker of secondary injury after intracerebral hemorrhage (ICH). However, knowledge about CE after ICH is insufficient. Whether CE has adverse effects on clinical outcomes of patients with ICH remains unknown. Therefore, we aimed to investigate the temporal pattern of CE and its association with clinical outcomes in patients with ICH.

METHODS

Data were derived from a randomized controlled study (comparing the deproteinized calf blood extract with placebo in patients with ICH). Intervention in this original study did not show any impact on hematoma and PHE volume, presence of CE, or clinical outcomes. We conducted our analysis in 20 patients who underwent magnetic resonance imaging with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) images at day 3 and within 7-12 days after symptom onset. CE was defined as an elevated DWI b1000 signal and an ADC value reduced by > 10% compared with the mirror area of interest in the perihematomal region. The modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), and Barthel Index (BI) were performed face to face at 30-day and 90-day follow-ups after ICH onset to assess the clinical outcomes of the patients.

RESULTS

CE was detected in nearly two thirds of patients with ICH in our study and seemed to be reversible. CE within 7-12 days, rather than at day 3 after symptom onset, was associated with poor clinical outcome (mRS 3-6) at the 30-day follow-up (P = 0.020). In addition, compared with those without CE, patients with CE within 7-12 days had more severe neurological impairment measured by NIHSS score (P = 0.024) and worse daily life quality measured by BI (P = 0.004) at both the 30- and 90-day follow-ups.

CONCLUSIONS

CE appears in the acute phase of ICH and might be reversible. CE within 7-12 days post ICH was related to poor outcomes, which provides a novel therapeutic target for ICH intervention.

Perihematomal Edema and Clinical Outcome After Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND

Perihematomal edema (PHE) has been proposed as a radiological marker of secondary injury and therapeutic target in intracerebral hemorrhage (ICH). We conducted a systematic review and meta-analysis to assess the prognostic impact of PHE on functional outcome and mortality in patients with ICH.

METHODS

We searched major databases through December 2020 using predefined keywords. Any study using logistic regression to examine the association between PHE or its growth and functional outcome was included. We examined the overall pooled effect and conducted secondary analyses to explore the impact of individual PHE measures on various outcomes separately. Study quality was assessed by three independent raters using the Newcastle-Ottawa Scale. Odds ratios (per 1-unit increase in PHE) and their confidence intervals (CIs) were log transformed and entered into a DerSimonian-Laird random-effects meta-analysis to obtain pooled estimates of the effect.

RESULTS

Twenty studies (n = 6633 patients) were included in the analysis. The pooled effect size for overall outcome was 1.05 (95% CI 1.02-1.08; p < 0.00). For the following secondary analyses, the effect size was weak: mortality (1.01; 95% CI 0.90-1.14), functional outcome (1.04; 95% CI 1.02-1.07), both 90-day (1.06; 95% CI 1.02-1.11), and in-hospital assessments (1.04; 95% CI 1.00-1.08). The effect sizes for PHE volume and PHE growth were 1.04 (95% CI 1.01-1.07) and 1.14 (95% CI 1.04-1.25), respectively. Heterogeneity across studies was substantial except for PHE growth.

CONCLUSIONS

This meta-analysis demonstrates that PHE volume within the first 72 h after ictus has a weak effect on functional outcome and mortality after ICH, whereas PHE growth might have a slightly larger impact during this time frame. Definitive conclusions are limited by the large variability of PHE measures, heterogeneity, and different evaluation time points between studies.

Brain microbleeds: distribution and influence on hematoma and perihematomal edema in patients with primary intracerebral hemorrhage

Brain microbleed is a marker of small vessel microhemorrhagic or microaneurysmal lesions, which may induce intracerebral hemorrhage (ICH). This study to prospectively evaluated the association between microbleeds, hematoma and perihematomal edema volume, and various clinical data, as well as patient outcome. Thirty-one patients with ICH and 31 healthy age-matched subjects were enrolled in our study. They were divided into two groups according to the presence or absence of microbleeds detected by MRI. Serial clinical and laboratory data were recorded. Modified Rankin Scale and Barthel Index were estimated three months after hemorrhage. The major location of microbleeds among patients with ICH was the basal ganglia. The volume of perihematomal edema was correlated with the initial hematoma volume on the first, fifth and seventh days after hemorrhage in patients with microbleeds. For patients without microbleeds, this correlation was also significant on the seventh day. Cerebral microbleeds in patients with ICH, especially in the basal ganglia region, represent micro-angiopathy, and are associated with leakage of blood and formation of perihemorrhage edema. Brain microbleeds found in patients with ICH warrant further investigation for evaluation of stroke risk.