Beyond Middle Meningeal Artery: Paradoxical Predominance Sign Predicts Additional Collaterals Supplying Chronic Subdural Hematoma.
Paradoxical predominance sign strongly predicts extra collaterals feeding subdural hematomas
Beyond Middle Meningeal Artery: Paradoxical Predominance Sign Predicts Additional Collaterals Supplying Chronic Subdural Hematoma.
Middle meningeal artery embolization (middle meningeal artery embolization) is an emerging treatment for chronic subdural hematoma (chronic subdural hematoma).
We aimed to explore the correlation between small MMA and collaterals, and identified a distinct angiographic phenomenon termed the "paradoxical predominance sign" where the contralateral MMA is larger than the ipsilateral MMA and hypothesized that this sign predicts the presence of collateral supply.
We performed a retrospective analysis of 125 patients with chronic subdural hematoma who underwent embolization at our center between October 2022 and August 2025.
collaterals were far more common with the paradoxical sign than typical predominance
In the general cohort, a smaller ipsilateral MMA (≤ 1.384 mm) was predictive of additional collaterals ( p < 0.001).
The paradoxical predominance sign was identified in 16 patients (12.8%).
Furthermore, within the ipsilateral predominance group, a diameter of ipsilateral MMA ≤ 1.462 mm indicated a significantly higher risk of collateral supply (53.70% vs .
Clinical outcomes, including recurrence and hematoma resorption, were comparable between groups, suggesting that successful embolization of identified collaterals neutralized the risk.
The hematoma membrane arterial supply in chronic subdural hematoma is heterogeneous, with additional collaterals contributing to middle meningeal artery embolization recurrence risk.
An ipsilateral MMA diameter ≤1.384 mm correlates with more collaterals, supporting prior hypotheses but with unproven generalizability.
The paradoxical predominance sign is a robust hemodynamic biomarker for identifying additional collaterals.