A Location-Specific Hyperdense Area Score Predicts Severe Mass Effect after Thrombectomy.

Area of Science:

• Neurology
• Radiology
• Critical Care Medicine

Background:

• Hyperdense areas (HDAs) on post-thrombectomy CT scans in large vessel occlusion stroke indicate blood-brain barrier injury.
• These injuries can lead to malignant edema or hemorrhagic transformation, potentially causing life-threatening mass effect.
• Severe mass effect often requires surgical intervention, such as decompressive craniectomy.

Purpose of the Study:

• To develop and validate a location-specific HDA score for predicting severe mass effect after thrombectomy.
• To improve risk stratification for patients with anterior circulation large vessel occlusion stroke.

Main Methods:

• A multicenter retrospective study of 865 patients with HDAs on post-thrombectomy CT.
• Developed a location-specific HDA score by including insula, subarachnoid, and ventricular compartments.
• Validated predictive models using LASSO regression, internal bootstrapping, and external data.

Main Results:

• The HDA score demonstrated a dose-response relationship with severe mass effect risk.
• Scores ≤3 indicated low risk (<10%) of severe mass effect with high negative predictive value (88.8%).
• An integrated model incorporating HDA features, glucose, NIHSS, and ASPECTS showed superior performance (AUC 0.801) compared to a clinical model (AUC 0.737).

Conclusions:

• A location-specific HDA score effectively identifies patients at high risk for severe mass effect post-thrombectomy.
• Integration into a clinical prediction model enhances risk stratification accuracy.
• This tool can guide timely intensive care management for stroke patients.