Middle meningeal artery embolization for organized chronic subdural hematoma combined with minimal evacuation surgery: Two case reports.

Organized chronic subdural hematoma (OCSDH) is a rare condition lacking standardized treatment protocols. Middle meningeal artery (MMA) embolization has recently demonstrated promising outcomes in managing chronic subdural hematoma (CSDH). We present 2 cases of OCSDH treated with endovascular embolization and minimal evacuation surgery. The first case involved an 83-year-old male with a history of left CSDH drainage, admitted urgently due to right hemiplegia and dysarthria. CT scans confirmed recurrent CSDH. A small craniotomy was performed to decompress the thick hematoma, followed by drain placement. Postoperative magnetic resonance imaging (MRI) indicated OCSDH. Seven days later, MMA embolization with 25% n-butyl-2-cyanoacrylate (NBCA) was performed under local anesthesia. The patient's symptoms improved, and the hematoma resolved within 6 months without recurrence. The second case involved a 76-year-old male with right CSDH and thrombocytopenia (platelet count of 19,000/µL), diagnosed with immune thrombocytopenia. MRI indicated OCSDH. Due to the risk associated with craniotomy, a burr hole perforation and MMA embolization were planned, accompanied by a platelet transfusion. Left MMA embolization with 20% NBCA was performed, followed by burr hole enlargement for decompression and drain placement. The patient's symptoms improved postoperatively, and his platelet count stabilized with steroid therapy and thrombopoietin. The hematoma resolved within 3 months without recurrence. These cases indicate that MMA embolization combined with small craniotomy or perforation may be an effective treatment strategy for OCSDH.