Discussion
ICH, Cerebral Hemorrhage, edema, inflammation, hematoma
EDEMA, CEREBRAL HEMORRHAGE, INFLAMMATION, DYSFUNCTION, SECONDARY, BLOOD, HEMATOMA
In the current study, a higher absolute PHE volume was associated with unfavorable outcomes after ICH. We further present evidence of CE in patients with ICH, providing a new insight to better understand the association between CE and functional outcomes. The results of this study showed that the existence of CE within 7 to 12 days post ICH was associated with poor functional outcomes at the 30- and 90-day follow-ups after ICH, whereas the association between CE at day 3 post ICH and outcomes was not statistically significant. This indicates that CE is an important component of PHE after ICH and might be a novel therapeutic target in future studies.Growing evidence suggests that the development of therapies targeting secondary brain injury after ICH is essential for improving the prognosis of patients with ICH. Numerous studies have demonstrated that PHE volume affects the prognosis of ICH. In the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT)-1/2 trials, growth in PHE had independent prognostic significance in acute ICH [CE, a premorbid precursor to extracellular ionic edema caused by the dysfunction or abnormal activation of ion pumps in astrocytes and endothelial cells, dominates the initial stage of PHE [Several underlying mechanisms might contribute to the formation of CE after ICH. Perihematomal glutamate deposition after ICH might be one of the potential reasons [Overall, CE is an important form of PHE in patients with ICH and might be reversible. The persistence of CE after ICH is related to poor clinical outcomes. Effective interventions to attenuate CE may help us develop novel intervention methods for ICH. Further studies are needed to provide deeper insight into the pathologies of CE formation. At the same time, we look forward to the results of ongoing clinical trials to confirm whether targeting inflammation and other potential pathologies of CE after ICH could attenuate CE and improve the prognosis of patients with ICH.Our study had several limitations. First, data of our study were derived from a clinical trial. Although it has been proven that the intervention conducted in that research did not have any impact on hematoma volume, PHE volume, presence of CE, or clinical outcomes, there might still be some potential effects on our conclusion. Second, MRI in our study was performed on day 3 and within 7 to 12 days after symptom onset, after the majority of hematoma expansion had occurred. Further studies are needed to observe CE at an earlier time point. Third, we could not determine the causal relationship between CE and adverse outcomes in patients with ICH because of the observational study design. Finally, the sample size of our study was small, and the participants were all from a single center in China, which made us unable to adjust for cofounders and might lead to bias. The generalizability of our findings to participants of other ethnicities and races needs to be confirmed in further studies with larger populations.