ISC 2026 | An update on the EMMA-Can trial of middle meningeal artery embolization in chronic subdural hematoma

The EMMA-Can trial was a landmark Canadian randomized study evaluating the embolization of middle meningeal artery. We call it as EMMA, E-M-M-A, as an adjunct to surgery for chronic subdural hematoma, a very common type of brain bleed that primarily affects older adults. Traditionally, these patients undergo surgical drainage, but recurrence rates have remained high. In our studies, we have seen 20 to 30% recurrence rates, meaning many patients require repeat procedures. EMMA-Can was designed to determine whether adding embolization, that is blocking of small arteries that feed the membrane responsible for recurrence, could reduce these rates. The results were very encouraging. The trial demonstrated a significant reduction in both radiographic and symptomatic recurrence at 90 days when embolization was added to the surgery. Radiographic recurrence dropped from roughly half of the patients in the control group to about 14% in the embolization group, that is roughly a four-fold decrease. Symptomatic recurrence was also substantially decreased by roughly six-fold. And importantly, the procedure was shown to be safe without an increase in major complications. These findings are important because they represent high-quality, randomized evidence supporting a shift in how we manage chronic subdural hematomas. For many patients, particularly older adults, reducing the need for repeat surgery can mean fewer hospitalizations, lower risks, and better overall recovery. The trial has also sparked important next steps. While the liquid embolic technique used in EMMA-Can was effective, it can be technically demanding and often requires general anesthesia. Current research, including our ongoing work, is focused on refining and simplifying embolization procedures to make them more accessible and potentially less invasive while maintaining the same benefits seen in the EMMA-Can trial. Overall, EMMA-Can has helped establish embolization as an evidence-based adjunct in chronic subdural hematoma management and has positioned Canada as one of the leaders in advancing minimally invasive neurovascular treatment for this increasingly common condition.

This transcript is AI-generated. While we strive for accuracy, please verify this copy with the video.