Recurrence of Chronic subdural hematoma caused by contralateral middle meningeal artery neovascularization

Abstract Background: Chronic subdural hematoma (cSDH) is one of the most common conditions affecting the nervous system that has a high incidence and mortality rate, especially in elderly individuals. Regardless of whether Burr-hole drainage, craniotomy, or embolization of the middle meningeal artery (MMA) is performed, there is still a risk of recurrence. We report a rare case of cSDH recurrence caused by neovascularization of the contralateral MMA. Ultimately, the patients underwent craniotomy for hematoma removal and embolization of the contralateral MMA achieves good results. Case presentation: A 74-year-old elderly male was diagnosed with a subdural hematoma involving the left frontal, temporal, parietal, and occipital regions. The patient underwent embolization of the MMA and burr-hole craniostomy with drainage to resolve the cSDH. The patient underwent continuous re-examination via head CT and MR, which showed a fresh left subdural hemorrhage and a gradual increase in the amount of subdural hematomas. Digital subtraction angiography (DSA) examination showed good occlusion of the original left MMA and a new vascular network of the right MMA crossing the midline to the left, with contrast agent leaking to the opposite side. Superselective embolization of the right MMA with Onyx was satisfactory. After MMA embolization, surgery to remove the intracranial hematoma was performed. The postoperative CT re‐examination showed no recurrence. Conclusion: This study indicates that the patient will develop cSDH recurrence through contralateral MMA neovascularization. Whichever the hematoma side is, to perform DSA of bilateral MMA and selective embolization of the MMA with positive radiological findings are proper treatment options and methods for reducing the rate of cSDH recurrence.