Recent research highlights the urgent need for timely surgical intervention for patients suffering from malignant ischemic strokes. A retrospective observational study involving 534 patients, conducted at the University Medical Center Göttingen, has developed the Malignant Stroke Indicator (MSI) score, which could revolutionize the approach to early identification and treatment of strokes at risk of causing significant brain damage.
Ischemic strokes remain one of the leading causes of mortality and disability worldwide, with over 10% of these patients developing malignant edema, leading to increased pressure on the brain and high mortality rates. Current standard treatment, decompressive hemicraniectomy (DHC), significantly increases survival rates, from 29% to as high as 78% after one year. Despite this, timely identification of patients requiring DHC has remained elusive, partly due to the lack of standardized criteria for assessment, prompting this new study to address the issue.
The study drew from clinical and radiological data from patients treated between 2010 and 2021. Researchers sought to identify parameters predictive of malignant strokes, using these determinants to create the MSI score. Key components of the scoring system include age under 70 (7 points), midline shift of the brain (up to 6 points), unsuccessful recanalization (i.e., TICI < 2b, 6 points), basal cistern effacement (4 points), and ASPECTS score of cerebral blood volume (CBV) below 6 (3 points). Notably, the MSI found significant discriminatory power with its optimal cutoff score set at 9, showing high predicted reliability for needing DHC with an astonishing area under the curve (AUC) of 0.90.
When applying the MSI score, patients who scored 9 or above were found to have a 22-fold increased probability of requiring DHC. This finding is particularly concerning, as many patients are often only assessed for DHC once overt symptoms of malignant edema begin to manifest. If implemented effectively, the MSI score could allow for pre-emptive surgical interventions, preventing the onset of severe brain damage.
The team identified other significant predictors for needing DHC, such as poor collateral circulation which had an odds ratio of 2.64, and the absence of prior strokes (7.28). Age is also significantly predictive, with younger individuals being at higher risk. These parameters are consistent with earlier findings but establish the MSI score as more comprehensive and discriminative compared to past models.
Looking at the results, the MSI score outperformed other predictive models, achieving importance particularly with its specificity of 91%, indicating it can correctly identify patients who do not need surgery. Conversely, its sensitivity of 69% raises the concern of missing lower-risk patients. Collectively, these insights position the MSI as not just another risk stratification tool but as potentially integral to clinical decision-making frameworks for acute ischemic stroke treatment.
Significantly, the study suggests the MSI score could guide treatment decisions within the first 24 hours post-stroke onset, allowing healthcare providers to act swiftly. Given its results, researchers recommend validation of the MSI score across different cohorts to confirm its robustness and applicability for routine clinical practices.
Functionality of the MSI score must be evaluated against clinical outcomes post-DHC as part of its validation process, ensuring it accurately predicts which patients will derive meaningful benefits from the procedure. For example, patients with younger age and other concerning radiological signs indicative of brain swelling are at risk of poor functional outcomes following DHC, even if surgical interventions were timely.
The introduction of the MSI score opens the door to significant advancements not only in individual patient care but also potentially altering clinical protocols for stroke management. The findings were presented at the German Society for Neurosurgery meeting, indicating the study's immediate relevance to the medical community. Given the dire statistics surrounding malignant ischemic strokes, the MSI holds promise as both a diagnostic and preventative measure, with expectations for its inclusion soon among stroke treatment guidelines.