Introduction: Chronic subdural hematoma (SDH) is a common pathology in neurosurgery, and is particularly difficult to treat due to high recurrence rates (11-33%) and complex medical comorbidities that tend to afflict the patient population. Recently, there have been several small case series published describing the use of middle meningeal artery (MMA) embolization as an alternative to surgery for treatment of new or recurrent chronic SDH. The authors argue that growth and recurrence of chronic SDH is due to repeated rebleeding from fragile neovasculature within the membrane that encapsulates the SDH, and that embolizing the MMA eliminates this process, allowing the brain to then resorb the collection over time. Here, we describe the largest series thus far of 57 cases of MMA embolization for chronic SDH.
Methods: IRB approval was obtained. MMA embolization was performed using angiography, selective microcatheterization of the MMA, and infusion of polyvinyl alcohol particles under blank fluoroscopic roadmap. Outcomes were assessed clinically and with follow-up CT scans at 1 day, 2 weeks, and 6 weeks post-procedure, and at additional intervals as indicated.
Results: MMA embolization was performed on 57 total SDHs in 46 patients. This includes up-front treatment for new (not previously treated) SDH in 40, for recurrence in 7, and prophylactic (soon after surgical evacuation) in 10. There were 3 mortalities (unrelated to the procedure), and no procedural complications. There were 4 (8.5%) cases of recurrence requiring surgical evacuation, and 32 (68.1%) that had resolution or reduction in size >50% of SDH at longest follow-up. Overall, 43 (91.5%) were stable or decreased in size and able to avoid surgery.
Conclusions: MMA embolization may represent a minimally-invasive alternative to surgery for new or recurrent chronic SDH. Given our encouraging results of 57 cases with a 91.5% long-term success rate, a large scale clinical trial is warranted.
Patient Care: Treatment of chronic subdural hematoma is difficult due to high recurrence rates and complex medical comborbidities that tend to afflict the patient population which often makes invasive procedures and stopping anticoagulation high risk. MMA embolization has shown great promise as a potential minimally invasive alternative to surgery which could be performed without using anesthesia or stopping blood thinners. Furthermore, it has shown promise as potentially an even more effective treatment strategy than surgery in terms of preventing recurrence. Our research helps make the case for a large scale clinical trial in order to further evaluate a procedure that may help many people with a difficult, debilitating illness.
Learning Objectives: 1. Endovascular embolization of the middle meningeal artery has recently been described as a potential treatment alternative to surgery for chronic subdural hematoma with encouraging preliminary results.
2. We present the largest case series thus far of 57 cases of chronic SDH in 46 patients treated with MMA embolization with an overall long-term success rate of 91.5% (defined as stable to decreased in size and able to avoid surgery).
3. MMA embolization could potentially be used as an up-front treatment for new chronic SDH, for recurrence after surgical evacuation, or prophylactically soon after surgical evacuation in order to reduce the risk of recurrence.